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Sample records for marmoset inferior colliculus

  1. Serotonin in the inferior colliculus.

    PubMed

    Hurley, Laura M; Thompson, Ann M; Pollak, George D

    2002-06-01

    It has been recognized for some time that serotonin fibers originating in raphe nuclei are present in the inferior colliculi of all mammalian species studied. More recently, serotonin has been found to modulate the responses of single inferior colliculus neurons to many types of auditory stimuli, ranging from simple tone bursts to complex species-specific vocalizations. The effects of serotonin are often quite strong, and for some neurons are also highly specific. A dramatic illustration of this is that serotonin can change the selectivity of some neurons for sounds, including species-specific vocalizations. These results are discussed in light of several theories on the function of serotonin in the IC, and of outstanding issues that remain to be addressed. PMID:12117504

  2. Corticofugal regulation of auditory sensitivity in the bat inferior colliculus.

    PubMed

    Jen, P H; Chen, Q C; Sun, X D

    1998-12-01

    Under free-field stimulation conditions, corticofugal regulation of auditory sensitivity of neurons in the central nucleus of the inferior colliculus of the big brown bat, Eptesicus fuscus, was studied by blocking activities of auditory cortical neurons with Lidocaine or by electrical stimulation in auditory cortical neuron recording sites. The corticocollicular pathway regulated the number of impulses, the auditory spatial response areas and the frequency-tuning curves of inferior colliculus neurons through facilitation or inhibition. Corticofugal regulation was most effective at low sound intensity and was dependent upon the time interval between acoustic and electrical stimuli. At optimal inter-stimulus intervals, inferior colliculus neurons had the smallest number of impulses and the longest response latency during corticofugal inhibition. The opposite effects were observed during corticofugal facilitation. Corticofugal inhibitory latency was longer than corticofugal facilitatory latency. Iontophoretic application of gamma-aminobutyric acid and bicuculline to inferior colliculus recording sites produced effects similar to what were observed during corticofugal inhibition and facilitation. We suggest that corticofugal regulation of central auditory sensitivity can provide an animal with a mechanism to regulate acoustic signal processing in the ascending auditory pathway.

  3. Inferior Colliculus Lesions Impair Eyeblink Conditioning in Rats

    ERIC Educational Resources Information Center

    Freeman, John H.; Halverson, Hunter E.; Hubbard, Erin M.

    2007-01-01

    The neural plasticity necessary for acquisition and retention of eyeblink conditioning has been localized to the cerebellum. However, the sources of sensory input to the cerebellum that are necessary for establishing learning-related plasticity have not been identified completely. The inferior colliculus may be a source of sensory input to the…

  4. A periodic network of neurochemical modules in the inferior colliculus.

    PubMed

    Chernock, Michelle L; Larue, David T; Winer, Jeffery A

    2004-02-01

    A new organization has been found in shell nuclei of rat inferior colliculus. Chemically specific modules with a periodic distribution fill about half of layer 2 of external cortex and dorsal cortex. Modules contain clusters of small glutamic acid decarboxylase-positive neurons and large boutons at higher density than in other inferior colliculus subdivisions. The modules are also present in tissue stained for parvalbumin, cytochrome oxidase, nicotinamide adenine dinucleotide phosphate-diaphorase, and acetylcholinesterase. Six to seven bilaterally symmetrical modules extend from the caudal extremity of the external cortex of the inferior colliculus to its rostral pole. Modules are from approximately 800 to 2200 microm long and have areas between 5000 and 40,000 microm2. Modules alternate with immunonegative regions. Similar modules are found in inbred and outbred strains of rat, and in both males and females. They are absent in mouse, squirrel, cat, bat, macaque monkey, and barn owl. Modules are immunonegative for glycine, calbindin, serotonin, and choline acetyltransferase. The auditory cortex and ipsi- and contralateral inferior colliculi project to the external cortex. Somatic sensory influences from the dorsal column nuclei and spinal trigeminal nucleus are the primary ascending sensory input to the external cortex; ascending auditory input to layer 2 is sparse. If the immunopositive modular neurons receive this input, the external cortex could participate in spatial orientation and somatic motor control through its intrinsic and extrinsic projections. PMID:14759566

  5. Combination-sensitive neurons in the inferior colliculus.

    PubMed

    Mittmann, D H; Wenstrup, J J

    1995-10-01

    We examined whether neurons in the inferior colliculus of the mustached bat (Pteronotus parnellii) are combination sensitive, responding to both low- and high-frequency components of the bat's sonar signal. These neurons, previously reported in the thalamus and cortex, analyze sonar target features including distance. Of 82 single units and 36 multiple units from the 58-112 kHz representations of the inferior colliculus, most (86%) displayed sensitivity to low-frequency sounds that was tuned in the range of the fundamental biosonar component (24-31 kHz). All histologically localized units were in the central nucleus of the inferior colliculus (ICC). There were two major types of combination-sensitive influences. Many neurons were facilitated by low-frequency sounds and selective for particular delays between the low- and high-frequency components. In other neurons, the low-frequency signal was inhibitory if presented simultaneously or a few milliseconds prior to the high-frequency signal. The results indicate that mechanisms creating specialized frequency comparisons and delay sensitivity in combination-sensitive neurons operate at the ICC or below. Since combination sensitivity or multipeaked tuning curves occur in the auditory systems of many species, ICC neurons in these animals may also respond to species-specific frequency combinations.

  6. Alignment of sound localization cues in the nucleus of the brachium of the inferior colliculus

    PubMed Central

    Young, Eric D.

    2014-01-01

    Accurate sound localization is based on three acoustic cues (interaural time and intensity difference and spectral cues from directional filtering by the pinna). In natural listening conditions, every spatial position of a sound source provides a unique combination of these three cues in “natural alignment.” Although neurons in the central nucleus (ICC) of the inferior colliculus (IC) are sensitive to multiple cues, they do not favor their natural spatial alignment. We tested for sensitivity to cue alignment in the nucleus of the brachium of the IC (BIN) in unanesthetized marmoset monkeys. The BIN receives its predominant auditory input from ICC and projects to the topographic auditory space map in the superior colliculus. Sound localization cues measured in each monkey were used to synthesize broadband stimuli with aligned and misaligned cues; spike responses to these stimuli were recorded in the BIN. We computed mutual information (MI) between the set of spike rates and the stimuli containing either aligned or misaligned cues. The results can be summarized as follows: 1) BIN neurons encode more information about auditory space when cues are aligned compared with misaligned. 2) Significantly more units prefer aligned cues in the BIN than in ICC. 3) An additive model based on summing the responses to stimuli with the localization cues varying individually accurately predicts the alignment preference with all cues varying. Overall, the results suggest that the BIN is the first site in the ascending mammalian auditory system that is tuned to natural combinations of sound localization cues. PMID:24671535

  7. Sensitivity of rat inferior colliculus neurons to frequency distributions.

    PubMed

    Herrmann, Björn; Parthasarathy, Aravindakshan; Han, Emily X; Obleser, Jonas; Bartlett, Edward L

    2015-11-01

    Stimulus-specific adaptation refers to a neural response reduction to a repeated stimulus that does not generalize to other stimuli. However, stimulus-specific adaptation appears to be influenced by additional factors. For example, the statistical distribution of tone frequencies has recently been shown to dynamically alter stimulus-specific adaptation in human auditory cortex. The present study investigated whether statistical stimulus distributions also affect stimulus-specific adaptation at an earlier stage of the auditory hierarchy. Neural spiking activity and local field potentials were recorded from inferior colliculus neurons of rats while tones were presented in oddball sequences that formed two different statistical contexts. Each sequence consisted of a repeatedly presented tone (standard) and three rare deviants of different magnitudes (small, moderate, large spectral change). The critical manipulation was the relative probability with which large spectral changes occurred. In one context the probability was high (relative to all deviants), while it was low in the other context. We observed larger responses for deviants compared with standards, confirming previous reports of increased response adaptation for frequently presented tones. Importantly, the statistical context in which tones were presented strongly modulated stimulus-specific adaptation. Physically and probabilistically identical stimuli (moderate deviants) in the two statistical contexts elicited different response magnitudes consistent with neural gain changes and thus neural sensitivity adjustments induced by the spectral range of a stimulus distribution. The data show that already at the level of the inferior colliculus stimulus-specific adaptation is dynamically altered by the statistical context in which stimuli occur. PMID:26354316

  8. Study of the inferior colliculus in patients with schizophrenia by magnetic resonance spectroscopy.

    PubMed

    Martinez-Granados, B; Martinez-Bisbal, M C; Sanjuan, J; Aguilar, E J; Marti-Bonmati, L; Molla, E; Celda, B

    2014-07-01

    INTRODUCTION. Previous studies have suggested morphometric and functional abnormalities in the inferior colliculus in patients with schizophrenia. Auditory hallucinations are one of the central symptoms in schizophrenia. In this complex and multidimensional event both attention and emotion are thought to play a key role. AIM. To study metabolic changes in the inferior colliculus, a nucleus integrated in the auditory pathway, in patients with schizophrenia and the possible relationship with auditory hallucinations. SUBJECTS AND METHODS. Magnetic resonance spectroscopic imaging studies were performed in 30 right-handed patients with chronic schizophrenia (19 of them with auditory hallucinations) and 28 controls. A magnetic resonance spectroscopic imaging 2D slice was acquired and the voxels representative of both inferior colliculi were selected. N-acetylaspartate (NAA), creatine (Cr) and choline (Cho) peak areas were measured. RESULTS. The patients with schizophrenia showed a NAA/Cr significant reduction in the right inferior colliculus compared to the control subjects. The metabolic data in the right inferior colliculus were correlated with emotional auditory hallucinations items. CONCLUSIONS. The contribution of the inferior colliculus on neural underpinnings of auditory hallucinations is particularly relevant for the right inferior colliculus and is centered on attention-emotional component of this symptom.

  9. Tinnitus-Related Changes in the Inferior Colliculus

    PubMed Central

    Berger, Joel I.; Coomber, Ben

    2015-01-01

    Tinnitus is highly complex, diverse, and difficult to treat, in part due to the fact that the underlying causes and mechanisms remain elusive. Tinnitus is generated within the auditory brain; however, consolidating our understanding of tinnitus pathophysiology is difficult due to the diversity of reported effects and the variety of implicated brain nuclei. Here, we focus on the inferior colliculus (IC), a midbrain structure that integrates the vast majority of ascending auditory information and projects via the thalamus to the auditory cortex. The IC is also a point of convergence for corticofugal input and input originating outside the auditory pathway. We review the evidence, from both studies with human subjects and from animal models, for the contribution the IC makes to tinnitus. Changes in the IC, caused by either noise exposure or drug administration, involve fundamental, heterogeneous alterations in the balance of excitation and inhibition. However, differences between hearing loss-induced pathology and tinnitus-related pathology are not well understood. Moreover, variability in tinnitus induction methodology has a significant impact on subsequent neural and behavioral changes, which could explain some of the seemingly contradictory data. Nonetheless, the IC is likely involved in the generation and persistence of tinnitus perception. PMID:25870582

  10. Dopaminergic Input to the Inferior Colliculus in Mice.

    PubMed

    Nevue, Alexander A; Elde, Cameron J; Perkel, David J; Portfors, Christine V

    2015-01-01

    The response of sensory neurons to stimuli can be modulated by a variety of factors including attention, emotion, behavioral context, and disorders involving neuromodulatory systems. For example, patients with Parkinson's disease (PD) have disordered speech processing, suggesting that dopamine alters normal representation of these salient sounds. Understanding the mechanisms by which dopamine modulates auditory processing is thus an important goal. The principal auditory midbrain nucleus, the inferior colliculus (IC), is a likely location for dopaminergic modulation of auditory processing because it contains dopamine receptors and nerve terminals immunoreactive for tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine synthesis. However, the sources of dopaminergic input to the IC are unknown. In this study, we iontophoretically injected a retrograde tracer into the IC of mice and then stained the tissue for TH. We also immunostained for dopamine beta-hydroxylase (DBH), an enzyme critical for the conversion of dopamine to norepinephrine, to differentiate between dopaminergic and noradrenergic inputs. Retrogradely labeled neurons that were positive for TH were seen bilaterally, with strong ipsilateral dominance, in the subparafascicular thalamic nucleus (SPF). All retrogradely labeled neurons that we observed in other brain regions were TH-negative. Projections from the SPF were confirmed using an anterograde tracer, revealing TH-positive and DBH-negative anterogradely labeled fibers and terminals in the IC. While the functional role of this dopaminergic input to the IC is not yet known, it provides a potential mechanism for context dependent modulation of auditory processing. PMID:26834578

  11. Serotonin shifts first-spike latencies of inferior colliculus neurons.

    PubMed

    Hurley, Laura M; Pollak, George D

    2005-08-24

    Many studies of neuromodulators have focused on changes in the magnitudes of neural responses, but fewer studies have examined neuromodulator effects on response latency. Across sensory systems, response latency is important for encoding not only the temporal structure but also the identity of stimuli. In the auditory system, latency is a fundamental response property that varies with many features of sound, including intensity, frequency, and duration. To determine the extent of neuromodulatory regulation of latency within the inferior colliculus (IC), a midbrain auditory nexus, the effects of iontophoretically applied serotonin on first-spike latencies were characterized in the IC of the Mexican free-tailed bat. Serotonin significantly altered the first-spike latencies in response to tones in 24% of IC neurons, usually increasing, but sometimes decreasing, latency. Serotonin-evoked changes in latency and spike count were not always correlated but sometimes occurred independently within individual neurons. Furthermore, in some neurons, the size of serotonin-evoked latency shifts depended on the frequency or intensity of the stimulus, as reported previously for serotonin-evoked changes in spike count. These results support the general conclusion that changes in latency are an important part of the neuromodulatory repertoire of serotonin within the auditory system and show that serotonin can change latency either in conjunction with broad changes in other aspects of neuronal excitability or in highly specific ways. PMID:16120790

  12. Visual modulation of auditory responses in the owl inferior colliculus.

    PubMed

    Bergan, Joseph F; Knudsen, Eric I

    2009-06-01

    The barn owl's central auditory system creates a map of auditory space in the external nucleus of the inferior colliculus (ICX). Although the crucial role visual experience plays in the formation and maintenance of this auditory space map is well established, the mechanism by which vision influences ICX responses remains unclear. Surprisingly, previous experiments have found that in the absence of extensive pharmacological manipulation, visual stimuli do not drive neural responses in the ICX. Here we investigated the influence of dynamic visual stimuli on auditory responses in the ICX. We show that a salient visual stimulus, when coincident with an auditory stimulus, can modulate auditory responses in the ICX even though the same visual stimulus may elicit no neural responses when presented alone. For each ICX neuron, the most effective auditory and visual stimuli were located in the same region of space. In addition, the magnitude of the visual modulation of auditory responses was dependent on the context of the stimulus presentation with novel visual stimuli eliciting consistently larger response modulations than frequently presented visual stimuli. Thus the visual modulation of ICX responses is dependent on the characteristics of the visual stimulus as well as on the spatial and temporal correspondence of the auditory and visual stimuli. These results demonstrate moment-to-moment visual enhancements of auditory responsiveness that, in the short-term, increase auditory responses to salient bimodal stimuli and in the long-term could serve to instruct the adaptive auditory plasticity necessary to maintain accurate auditory orienting behavior. PMID:19321633

  13. Lagged cells in the inferior colliculus of the awake ferret

    PubMed Central

    Shechter, Barak; Marvit, Peter; Depireux, Didier A

    2010-01-01

    Neurons in primary auditory cortex (AI) encode complex features of the spectral content of sound, such as direction selectivity. Recent findings of temporal symmetry in AI predict a specific organization of the subcortical input into cortex that contributes to the emergence of direction selectivity. We demonstrate two sub-populations of neurons in the central nucleus of the inferior colliculus, which differ in their steady-state temporal response profile: lagged and non-lagged. The lagged cells (23%) are shifted in temporal phase with respect to non-lagged cells and are characterized by an “inhibition first” and delayed excitation in their spectro-temporal receptive fields. Non-lagged cells (77%) have a canonical “excitation first” response. However, we find no difference in the response onset latency to pure tone stimuli between the two sub-populations. Given the homogeneity of tonal response latency, we predict that these lagged cells receive inhibitory input mediated by cortical feedback projections. PMID:20092554

  14. Spectral and Temporal Modulation Tradeoff in the Inferior Colliculus

    PubMed Central

    Rodríguez, Francisco A.; Read, Heather L.

    2010-01-01

    The cochlea encodes sounds through frequency-selective channels that exhibit low-pass modulation sensitivity. Unlike the cochlea, neurons in the auditory midbrain are tuned for spectral and temporal modulations found in natural sounds, yet the role of this transformation is not known. We report a distinct tradeoff in modulation sensitivity and tuning that is topographically ordered within the central nucleus of the inferior colliculus (CNIC). Spectrotemporal receptive fields (STRFs) were obtained with 16-channel electrodes inserted orthogonal to the isofrequency lamina. Surprisingly, temporal and spectral characteristics exhibited an opposing relationship along the tonotopic axis. For low best frequencies (BFs), units were selective for fast temporal and broad spectral modulations. A systematic progression was observed toward slower temporal and finer spectral modulation sensitivity at high BF. This tradeoff was strongly reflected in the arrangement of excitation and inhibition and, consequently, in the modulation tuning characteristics. Comparisons with auditory nerve fibers show that these trends oppose the pattern imposed by the peripheral filters. These results suggest that spectrotemporal preferences are reordered within the tonotopic axis of the CNIC. This topographic organization has profound implications for the coding of spectrotemporal features in natural sounds and could underlie a number of perceptual phenomena. PMID:20018831

  15. Responses of Inferior Colliculus Neurons to Double Harmonic Tones

    PubMed Central

    Li, Hongzhe

    2008-01-01

    The auditory system can segregate sounds that overlap in time and frequency, if the sounds differ in acoustic properties such as fundamental frequency (f0). However, the neural mechanisms that underlie this ability are poorly understood. Responses of neurons in the inferior colliculus (IC) of the anesthetized chinchilla were measured. The stimuli were harmonic tones, presented alone (single harmonic tones) and in the presence of a second harmonic tone with a different f0 (double harmonic tones). Responses to single harmonic tones exhibited no stimulus-related temporal pattern, or in some cases, a simple envelope modulated at f0. Responses to double harmonic tones exhibited complex slowly modulated discharge patterns. The discharge pattern varied with the difference in f0 and with characteristic frequency. The discharge pattern also varied with the relative levels of the two tones; complex temporal patterns were observed when levels were equal, but as the level difference increased, the discharge pattern reverted to that associated with single harmonic tones. The results indicated that IC neurons convey information about simultaneous sounds in their temporal discharge patterns and that the patterns are produced by interactions between adjacent components in the spectrum. The representation is “low-resolution,” in that it does not convey information about single resolved components from either individual sound. PMID:17913991

  16. Dopaminergic Input to the Inferior Colliculus in Mice

    PubMed Central

    Nevue, Alexander A.; Elde, Cameron J.; Perkel, David J.; Portfors, Christine V.

    2016-01-01

    The response of sensory neurons to stimuli can be modulated by a variety of factors including attention, emotion, behavioral context, and disorders involving neuromodulatory systems. For example, patients with Parkinson’s disease (PD) have disordered speech processing, suggesting that dopamine alters normal representation of these salient sounds. Understanding the mechanisms by which dopamine modulates auditory processing is thus an important goal. The principal auditory midbrain nucleus, the inferior colliculus (IC), is a likely location for dopaminergic modulation of auditory processing because it contains dopamine receptors and nerve terminals immunoreactive for tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine synthesis. However, the sources of dopaminergic input to the IC are unknown. In this study, we iontophoretically injected a retrograde tracer into the IC of mice and then stained the tissue for TH. We also immunostained for dopamine beta-hydroxylase (DBH), an enzyme critical for the conversion of dopamine to norepinephrine, to differentiate between dopaminergic and noradrenergic inputs. Retrogradely labeled neurons that were positive for TH were seen bilaterally, with strong ipsilateral dominance, in the subparafascicular thalamic nucleus (SPF). All retrogradely labeled neurons that we observed in other brain regions were TH-negative. Projections from the SPF were confirmed using an anterograde tracer, revealing TH-positive and DBH-negative anterogradely labeled fibers and terminals in the IC. While the functional role of this dopaminergic input to the IC is not yet known, it provides a potential mechanism for context dependent modulation of auditory processing. PMID:26834578

  17. Spectral integration in the inferior colliculus of the mustached bat.

    PubMed

    Leroy, S A; Wenstrup, J J

    2000-11-15

    Acoustic behaviors including orientation and social communication depend on neural integration of information across the sound spectrum. In many species, spectral integration is performed by combination-sensitive neurons, responding best when distinct spectral elements in sounds are combined. These are generally considered a feature of information processing in the auditory forebrain. In the mustached bat's inferior colliculus (IC), they are common in frequency representations associated with sonar signals but have not been reported elsewhere in this bat's IC or the IC of other species. We examined the presence of combination-sensitive neurons in frequency representations of the mustached bat's IC not associated with biosonar. Seventy-five single-unit responses were recorded with the best frequencies in 10-23 or 32-47 kHz bands. Twenty-six displayed single excitatory tuning curves in one band with no additional responsiveness to a second signal in another band. The remaining 49 responded to sounds in both 10-23 and 32-47 kHz bands, but response types varied. Sounds in the higher band were usually excitatory, whereas sounds in the lower band either facilitated or inhibited responses to the higher frequency signal. Interactions were usually strongest when the higher and lower frequency stimuli were presented simultaneously, but the strength of interactions varied. Over one-third of the neurons formed a distinct subset; they responded most sensitively to bandpass noise, and all were combination sensitive. We suggest that these combination-sensitive interactions are activated by elements of mustached bat social vocalizations. If so, neuronal integration characterizing analysis of social vocalizations in many species occurs in the IC.

  18. Inputs to combination-sensitive neurons of the inferior colliculus.

    PubMed

    Wenstrup, J J; Mittmann, D H; Grose, C D

    1999-07-12

    In the mustached bat, combination-sensitive neurons display integrative responses to combinations of acoustic elements in biosonar or social vocalizations. One type of combination-sensitive neuron responds to multiple harmonics of the frequency-modulated (FM) components in the sonar pulse and echo of the bat. These neurons, termed FM-FM neurons, are sensitive to the pulse-echo delay and may encode the distance of sonar targets. FM-FM neurons are common in high-frequency regions of the central nucleus of the inferior colliculus (ICC) and may be created there. If so, they must receive low-frequency inputs in addition to the expected high-frequency inputs. We placed single deposits of a tracer at FM-FM recording sites in the ICC and then analyzed retrograde labeling in the brainstem and midbrain. We were particularly interested in labeling patterns suggestive of low-frequency input to these FM-FM neurons. In most nuclei containing labeled cells, there was a single focus of labeling in regions thought to be responsive to high-frequency sounds. More complex labeling patterns were observed in three nuclei. In the anteroventral cochlear nucleus, labeling in the anterior and marginal cell divisions occurred in regions thought to respond to low-frequency sounds. This labeling comprised 6% of total brainstem labeled cells. Labeling in the intermediate nucleus of the lateral lemniscus and the magnocellular part of the ventral nucleus of the lateral lemniscus together comprised nearly 40% of all labeled cells. In both nuclei, multiple foci of labeling occurred. These different foci may represent groups of cells tuned to different frequency bands. Thus, one or more of these three nuclei may provide low-frequency input to high-frequency-sensitive cells in the ICC, creating FM-FM responses. We also examined whether ICC neurons responsive to lower frequencies project to high-frequency-sensitive ICC regions; only 0.15% of labeling originated from these lower frequency

  19. Cytoarchitectural and Functional Abnormalities of the Inferior Colliculus in Sudden Unexplained Perinatal Death

    PubMed Central

    Lavezzi, Anna M.; Pusiol, Teresa; Matturri, Luigi

    2015-01-01

    Abstract The inferior colliculus is a mesencephalic structure endowed with serotonergic fibers that plays an important role in the processing of acoustic information. The implication of the neuromodulator serotonin also in the aetiology of sudden unexplained fetal and infant death syndromes and the demonstration in these pathologies of developmental alterations of the superior olivary complex (SOC), a group of pontine nuclei likewise involved in hearing, prompted us to investigate whether the inferior colliculus may somehow contribute to the pathogenetic mechanism of unexplained perinatal death. Therefore, we performed in a wide set of fetuses and infants, aged from 33 gestational weeks to 7 postnatal months and died of both known and unknown cause, an in-depth anatomopathological analysis of the brainstem, particularly of the midbrain. Peculiar neuroanatomical and functional abnormalities of the inferior colliculus, such as hypoplasia/structural disarrangement and immunonegativity or poor positivity of serotonin, were exclusively found in sudden death victims, and not in controls. In addition, these alterations were frequently related to dysgenesis of connected structures, precisely the raphé nuclei and the superior olivary complex, and to nicotine absorption in pregnancy. We propose, on the basis of these results, the involvement of the inferior colliculus in more important functions than those related to hearing, as breathing and, more extensively, all the vital activities, and then in pathological conditions underlying a sudden death in vulnerable periods of the autonomic nervous system development, particularly associated to harmful risk factors as cigarette smoking. PMID:25674737

  20. Responses from two firing patterns in inferior colliculus neurons to stimulation of the lateral lemniscus dorsal nucleus

    PubMed Central

    Li, Xiao-ting; Wang, Ning-yu; Wang, Yan-jun; Xu, Zhi-qing; Liu, Jin-feng; Bai, Yun-fei; Dai, Jin-sheng; Zhao, Jing-yi

    2016-01-01

    The γ-aminobutyric acid neurons (GABAergic neurons) in the inferior colliculus are classified into various patterns based on their intrinsic electrical properties to a constant current injection. Although this classification is associated with physiological function, the exact role for neurons with various firing patterns in acoustic processing remains poorly understood. In the present study, we analyzed characteristics of inferior colliculus neurons in vitro, and recorded responses to stimulation of the dorsal nucleus of the lateral lemniscus using the whole-cell patch clamp technique. Seven inferior colliculus neurons were tested and were classified into two firing patterns: sustained-regular (n = 4) and sustained-adapting firing patterns (n = 3). The majority of inferior colliculus neurons exhibited slight changes in response to stimulation and bicuculline. The responses of one neuron with a sustained-adapting firing pattern were suppressed after stimulation, but recovered to normal levels following application of the γ-aminobutyric acid receptor antagonist. One neuron with a sustained-regular pattern showed suppressed stimulation responses, which were not affected by bicuculline. Results suggest that GABAergic neurons in the inferior colliculus exhibit sustained-regular or sustained-adapting firing patterns. Additionally, GABAergic projections from the dorsal nucleus of the lateral lemniscus to the inferior colliculus are associated with sound localization. The different neuronal responses of various firing patterns suggest a role in sound localization. A better understanding of these mechanisms and functions will provide better clinical treatment paradigms for hearing deficiencies. PMID:27335563

  1. Adaptive adjustment of connectivity in the inferior colliculus revealed by focal pharmacological inactivation.

    PubMed

    Gold, J I; Knudsen, E I

    2001-04-01

    In the midbrain sound localization pathway of the barn owl, a map of auditory space is synthesized in the external nucleus of the inferior colliculus (ICX) and transmitted to the optic tectum. Early auditory experience shapes these maps of auditory space in part by modifying the tuning of the constituent neurons for interaural time difference (ITD), a primary cue for sound-source azimuth. Here we show that these adaptive modifications in ITD tuning correspond to changes in the pattern of connectivity within the inferior colliculus. We raised owls with an acoustic filtering device in one ear that caused frequency-dependent changes in sound timing and level. As reported previously, device rearing shifted the representation of ITD in the ICX and tectum but not in the primary source of input to the ICX, the central nucleus of the inferior colliculus (ICC). We applied the local anesthetic lidocaine (QX-314) iontophoretically in the ICC to inactivate small populations of neurons that represented particular values of frequency and ITD. We measured the effect of this inactivation in the optic tecta of a normal owl and owls raised with the device. In the normal owl, inactivation at a critical site in the ICC eliminated responses in the tectum to the frequency-specific ITD value represented at the site of inactivation in the ICC. The location of this site was consistent with the known pattern of ICC-ICX-tectum connectivity. In the device-reared owls, adaptive changes in the representation of ITD in the tectum corresponded to dramatic and predictable changes in the locations of the critical sites of inactivation in the ICC. Given that the abnormal representation of ITD in the tectum depended on frequency and was likely conveyed directly from the ICX, these results suggest that experience causes large-scale, frequency-specific adjustments in the pattern of connectivity between the ICC and the ICX. PMID:11287481

  2. Serotonin modulates responses to species-specific vocalizations in the inferior colliculus.

    PubMed

    Hurley, Laura M; Pollak, George D

    2005-06-01

    Neuromodulators such as serotonin are capable of altering the neural processing of stimuli across many sensory modalities. In the inferior colliculus, a major midbrain auditory gateway, serotonin alters the way that individual neurons respond to simple tone bursts and linear frequency modulated sweeps. The effects of serotonin are complex, and vary among neurons. How serotonin transforms the responses to spectrotemporally complex sounds of the type normally heard in natural settings has been poorly examined. To explore this issue further, the effects of iontophoretically applied serotonin on the responses of individual inferior colliculus neurons to a variety of recorded species-specific vocalizations were examined. These experiments were performed in the Mexican free-tailed bat, a species that uses a rich repertoire of vocalizations for the purposes of communication as well as echolocation. Serotonin frequently changed the number of recorded calls that were capable of evoking a response from individual neurons, sometimes increasing (15% of serotonin-responsive neurons), but usually decreasing (62% of serotonin-responsive neurons), this number. A functional consequence of these serotonin-evoked changes would be to change the population response to species-specific vocalizations. PMID:15830241

  3. An Overrepresentation of High Frequencies in the Mouse Inferior Colliculus Supports the Processing of Ultrasonic Vocalizations

    PubMed Central

    Garcia-Lazaro, Jose A.; Shepard, Kathryn N.; Miranda, Jason A.; Liu, Robert C.; Lesica, Nicholas A.

    2015-01-01

    Mice are of paramount importance in biomedical research and their vocalizations are a subject of interest for researchers across a wide range of health-related disciplines due to their increasingly important value as a phenotyping tool in models of neural, speech and language disorders. However, the mechanisms underlying the auditory processing of vocalizations in mice are not well understood. The mouse audiogram shows a peak in sensitivity at frequencies between 15-25 kHz, but weaker sensitivity for the higher ultrasonic frequencies at which they typically vocalize. To investigate the auditory processing of vocalizations in mice, we measured evoked potential, single-unit, and multi-unit responses to tones and vocalizations at three different stages along the auditory pathway: the auditory nerve and the cochlear nucleus in the periphery, and the inferior colliculus in the midbrain. Auditory brainstem response measurements suggested stronger responses in the midbrain relative to the periphery for frequencies higher than 32 kHz. This result was confirmed by single- and multi-unit recordings showing that high ultrasonic frequency tones and vocalizations elicited responses from only a small fraction of cells in the periphery, while a much larger fraction of cells responded in the inferior colliculus. These results suggest that the processing of communication calls in mice is supported by a specialization of the auditory system for high frequencies that emerges at central stations of the auditory pathway. PMID:26244986

  4. An Overrepresentation of High Frequencies in the Mouse Inferior Colliculus Supports the Processing of Ultrasonic Vocalizations.

    PubMed

    Garcia-Lazaro, Jose A; Shepard, Kathryn N; Miranda, Jason A; Liu, Robert C; Lesica, Nicholas A

    2015-01-01

    Mice are of paramount importance in biomedical research and their vocalizations are a subject of interest for researchers across a wide range of health-related disciplines due to their increasingly important value as a phenotyping tool in models of neural, speech and language disorders. However, the mechanisms underlying the auditory processing of vocalizations in mice are not well understood. The mouse audiogram shows a peak in sensitivity at frequencies between 15-25 kHz, but weaker sensitivity for the higher ultrasonic frequencies at which they typically vocalize. To investigate the auditory processing of vocalizations in mice, we measured evoked potential, single-unit, and multi-unit responses to tones and vocalizations at three different stages along the auditory pathway: the auditory nerve and the cochlear nucleus in the periphery, and the inferior colliculus in the midbrain. Auditory brainstem response measurements suggested stronger responses in the midbrain relative to the periphery for frequencies higher than 32 kHz. This result was confirmed by single- and multi-unit recordings showing that high ultrasonic frequency tones and vocalizations elicited responses from only a small fraction of cells in the periphery, while a much larger fraction of cells responded in the inferior colliculus. These results suggest that the processing of communication calls in mice is supported by a specialization of the auditory system for high frequencies that emerges at central stations of the auditory pathway.

  5. A neural network model of the inferior colliculus with modifiable lateral inhibitory synapses for human echolocation.

    PubMed

    Hoshino, Osamu; Kuroiwa, Kazuharu

    2002-03-01

    We propose a neural network model of the inferior colliculus (IC) for human echolocation. Neuronal mechanisms for human echolocation were investigated by simulating the model. The model consists of the neural networks of the central nucleus (ICc) and external nucleus (ICx) of the inferior colliculus. The neurons of the ICc receive interaural sound stimuli via multiple contralateral delay lines and a single ipsilateral delay line. The neurons of the ICc send output signals to the neurons of the ICx in a convergent manner. We stimulated the ICc with pairs of a direct sound (a sonar sound) and an echo sound (the reflection from an object). Information about the distance between the model and the object is expressed by the delay time of the echo sound with respect to the direct sound. The results presented here show that neurons of the ICc responsive to interaural onset time differences contribute to the creation of an auditory distance map in the ICx. We trained the model with various pairs of direct-echo sounds and modified synaptic connection strengths of the networks according to the Hebbian rule. It is shown that self-organized long-term depression of lateral inhibitory synaptic connections plays an important role in enhancing echolocation skills.

  6. Spectral integration in the inferior colliculus: role of glycinergic inhibition in response facilitation.

    PubMed

    Wenstrup, J; Leroy, S A

    2001-02-01

    This study examined the contribution of glycinergic inhibition to the time-sensitive spectral integration performed by neurons in the inferior colliculus of the mustached bat (Pteronotus parnellii). These neurons are sometimes called combination-sensitive because they display facilitatory (or inhibitory) responses to the combination of distinct spectral elements in sonar or social vocalizations. Present in a wide range of vertebrates, their temporally and spectrally selective integration is thought to endow them with the ability to discriminate among social vocalizations or to analyze particular cues concerning sonar targets. The mechanisms that underlie these responses or the sites in the auditory system where they are created are not known. We examined combination-sensitive neurons that are facilitated by the presentation of two different harmonic elements of the bat's sonar call and echo. Responses of 24 single units were recorded before and during local application of strychnine, an antagonist of glycinergic inhibition. For each of the 24 units, strychnine application eliminated or greatly reduced temporally sensitive facilitation. There was no difference in this effect for neurons tuned to frequencies associated with the frequency-modulated or the constant-frequency sonar components. These results are unusual because glycine is considered to be an inhibitory neurotransmitter, but here it appears to be essential for the expression of combination-sensitive facilitation. The findings provide strong evidence that facilitatory combination-sensitive response properties present throughout the mustached bat's auditory midbrain, thalamus, and cortex originate through neural interactions in the inferior colliculus.

  7. GABAA-Mediated Inhibition Modulates Stimulus-Specific Adaptation in the Inferior Colliculus

    PubMed Central

    Pérez-González, David; Hernández, Olga; Covey, Ellen; Malmierca, Manuel S.

    2012-01-01

    The ability to detect novel sounds in a complex acoustic context is crucial for survival. Neurons from midbrain through cortical levels adapt to repetitive stimuli, while maintaining responsiveness to rare stimuli, a phenomenon called stimulus-specific adaptation (SSA). The site of origin and mechanism of SSA are currently unknown. We used microiontophoretic application of gabazine to examine the role of GABAA-mediated inhibition in SSA in the inferior colliculus, the midbrain center for auditory processing. We found that gabazine slowed down the process of adaptation to high probability stimuli but did not abolish it, with response magnitude and latency still depending on the probability of the stimulus. Blocking GABAA receptors increased the firing rate to high and low probability stimuli, but did not completely equalize the responses. Together, these findings suggest that GABAA-mediated inhibition acts as a gain control mechanism that enhances SSA by modifying the responsiveness of the neuron. PMID:22479591

  8. Temporal properties of inferior colliculus neurons to photonic stimulation in the cochlea.

    PubMed

    Tan, Xiaodong; Young, Hunter; Matic, Agnella Izzo; Zirkle, Whitney; Rajguru, Suhrud; Richter, Claus-Peter

    2015-08-01

    Infrared neural stimulation (INS) may be beneficial in auditory prostheses because of its spatially selective activation of spiral ganglion neurons. However, the response properties of single auditory neurons to INS and the possible contributions of its optoacoustic effects are yet to be examined. In this study, the temporal properties of auditory neurons in the central nucleus of the inferior colliculus (ICC) of guinea pigs in response to INS were characterized. Spatial selectivity of INS was observed along the tonotopically organized ICC. Trains of laser pulses and trains of acoustic clicks were used to evoke single unit responses in ICC of normal hearing animals. In response to INS, ICC neurons showed lower limiting rates, longer latencies, and lower firing efficiencies. In deaf animals, ICC neurons could still be stimulated by INS while unresponsive to acoustic stimulation. The site and spatial selectivity of INS both likely shaped the temporal properties of ICC neurons.

  9. Temporal properties of inferior colliculus neurons to photonic stimulation in the cochlea

    PubMed Central

    Tan, Xiaodong; Young, Hunter; Matic, Agnella Izzo; Zirkle, Whitney; Rajguru, Suhrud; Richter, Claus-Peter

    2015-01-01

    Infrared neural stimulation (INS) may be beneficial in auditory prostheses because of its spatially selective activation of spiral ganglion neurons. However, the response properties of single auditory neurons to INS and the possible contributions of its optoacoustic effects are yet to be examined. In this study, the temporal properties of auditory neurons in the central nucleus of the inferior colliculus (ICC) of guinea pigs in response to INS were characterized. Spatial selectivity of INS was observed along the tonotopically organized ICC. Trains of laser pulses and trains of acoustic clicks were used to evoke single unit responses in ICC of normal hearing animals. In response to INS, ICC neurons showed lower limiting rates, longer latencies, and lower firing efficiencies. In deaf animals, ICC neurons could still be stimulated by INS while unresponsive to acoustic stimulation. The site and spatial selectivity of INS both likely shaped the temporal properties of ICC neurons. PMID:26311831

  10. Development of Intrinsic Connectivity in the Central Nucleus of the Mouse Inferior Colliculus

    PubMed Central

    Sturm, Joshua; Nguyen, Tuan

    2014-01-01

    The inferior colliculus (IC) in the mammalian midbrain is the major subcortical auditory integration center receiving ascending inputs from almost all auditory brainstem nuclei as well as descending inputs from the thalamus and cortex. In addition to these extrinsic inputs, the IC also contains a dense network of local, intracollicular connections, which are thought to provide gain control and contribute to the selectivity for complex acoustic features. However, in contrast to the organization of extrinsic IC afferents, the development and functional organization of intrinsic connections in the IC has remained poorly understood. Here we used laser-scanning photostimulation with caged glutamate to characterize the spatial distribution and strength of local synaptic connections in the central nucleus of the inferior colliculus of newborn mice until after hearing onset (P2-P22). We demonstrate the presence of an extensive excitatory and inhibitory intracollicular network already at P2. Excitatory and inhibitory synaptic maps to individual IC neurons formed continuous maps that largely overlapped with each other and that were aligned with the presumed isofrequency axis of the central nucleus of the IC. Although this characteristic organization was present throughout the first three postnatal weeks, the size of input maps was developmentally regulated as input maps underwent an expansion during the first week that was followed by a dramatic refinement after hearing onset. These changes occurred in parallel for excitatory and inhibitory input maps. However, the functional elimination of intrinsic connections was greater for excitatory than for inhibitory connections, resulting in a predominance of intrinsic inhibition after hearing onset. PMID:25378168

  11. Deactivation of the inferior colliculus by cooling demonstrates intercollicular modulation of neuronal activity.

    PubMed

    Orton, Llwyd D; Poon, Paul W F; Rees, Adrian

    2012-01-01

    The auditory pathways coursing through the brainstem are organized bilaterally in mirror image about the midline and at several levels the two sides are interconnected. One of the most prominent points of interconnection is the commissure of the inferior colliculus (CoIC). Anatomical studies have revealed that these fibers make reciprocal connections which follow the tonotopic organization of the inferior colliculus (IC), and that the commissure contains both excitatory and, albeit fewer, inhibitory fibers. The role of these connections in sound processing is largely unknown. Here we describe a method to address this question in the anaesthetized guinea pig. We used a cryoloop placed on one IC to produce reversible deactivation while recording electrophysiological responses to sounds in both ICs. We recorded single units, multi-unit clusters and local field potentials (LFPs) before, during and after cooling. The degree and spread of cooling was measured with a thermocouple placed in the IC and other auditory structures. Cooling sufficient to eliminate firing was restricted to the IC contacted by the cryoloop. The temperature of other auditory brainstem structures, including the contralateral IC and the cochlea were minimally affected. Cooling below 20°C reduced or eliminated the firing of action potentials in frequency laminae at depths corresponding to characteristic frequencies up to ~8 kHz. Modulation of neural activity also occurred in the un-cooled IC with changes in single unit firing and LFPs. Components of LFPs signaling lemniscal afferent input to the IC showed little change in amplitude or latency with cooling, whereas the later components, which likely reflect inter- and intra-collicular processing, showed marked changes in form and amplitude. We conclude that the cryoloop is an effective method of selectively deactivating one IC in guinea pig, and demonstrate that auditory processing in the IC is strongly influenced by the other. PMID:23248587

  12. Deactivation of the inferior colliculus by cooling demonstrates intercollicular modulation of neuronal activity

    PubMed Central

    Orton, Llwyd D.; Poon, Paul W. F.; Rees, Adrian

    2012-01-01

    The auditory pathways coursing through the brainstem are organized bilaterally in mirror image about the midline and at several levels the two sides are interconnected. One of the most prominent points of interconnection is the commissure of the inferior colliculus (CoIC). Anatomical studies have revealed that these fibers make reciprocal connections which follow the tonotopic organization of the inferior colliculus (IC), and that the commissure contains both excitatory and, albeit fewer, inhibitory fibers. The role of these connections in sound processing is largely unknown. Here we describe a method to address this question in the anaesthetized guinea pig. We used a cryoloop placed on one IC to produce reversible deactivation while recording electrophysiological responses to sounds in both ICs. We recorded single units, multi-unit clusters and local field potentials (LFPs) before, during and after cooling. The degree and spread of cooling was measured with a thermocouple placed in the IC and other auditory structures. Cooling sufficient to eliminate firing was restricted to the IC contacted by the cryoloop. The temperature of other auditory brainstem structures, including the contralateral IC and the cochlea were minimally affected. Cooling below 20°C reduced or eliminated the firing of action potentials in frequency laminae at depths corresponding to characteristic frequencies up to ~8 kHz. Modulation of neural activity also occurred in the un-cooled IC with changes in single unit firing and LFPs. Components of LFPs signaling lemniscal afferent input to the IC showed little change in amplitude or latency with cooling, whereas the later components, which likely reflect inter- and intra-collicular processing, showed marked changes in form and amplitude. We conclude that the cryoloop is an effective method of selectively deactivating one IC in guinea pig, and demonstrate that auditory processing in the IC is strongly influenced by the other. PMID:23248587

  13. Regional and laminar distribution of cortical neurons projecting to either superior or inferior colliculus in the hedgehog tenrec.

    PubMed

    Künzle, H

    1995-01-01

    Retrograde tracer substances were injected into either the inferior or the superior colliculus in the Madagascan hedgehog tenrec, Echinops telfairi (Insectivora), to reveal the laminar and regional distribution of corticotectal cells and to correlate the labeled areas with architectural data. The tenrecs, taken from our breeding colony, have one of the least differentiated cerebral cortices among mammals, and experimental investigations of such brains are important for the understanding of the evolution and intrinsic organization of the more highly differentiated cerebral cortex in other placental mammals. Following injections into the inferior colliculus, cortical neurons were labeled bilaterally, with an ipsilateral predominance. Most labeled cells were found in the caudolateral hemisphere, area 4 as defined by Rehkämper (1981); some were in the somatosensorimotor cortex, as defined in a previous study. The labeled neurons in area 4 were located in layers V and VI, forming two bands of cells separated from each other by a poorly labeled interspace. A further subdivision of this presumed auditory region could not be achieved. This entire area was also weakly labeled following tracer injections into the superior colliculus. The labeled cells, however, were restricted to layer V of the ipsilateral side. The most consistent sites of labeled cells following injections into the superior colliculus were found in layer V of the ipsilateral caudomedial hemisphere, Rehkämper's caudal area 3, and the transitional zone adjacent to the retrosplenial cortex. This area is small in comparison to the entire region that was found in this study to project to the superior colliculus. The superior colliculus also receives projections from the ipsilateral sensorimotor and cingulate cortices. The latter projections are particularly striking in comparison to other mammals because they originate from along the entire rostrocaudal extent of the cingulate/retrosplenial region.

  14. Different serotonin receptor agonists have distinct effects on sound-evoked responses in inferior colliculus.

    PubMed

    Hurley, Laura M

    2006-11-01

    The neuromodulator serotonin has a complex set of effects on the auditory responses of neurons within the inferior colliculus (IC), a midbrain auditory nucleus that integrates a wide range of inputs from auditory and nonauditory sources. To determine whether activation of different types of serotonin receptors is a source of the variability in serotonergic effects, four selective agonists of serotonin receptors in the serotonin (5-HT) 1 and 5-HT2 families were iontophoretically applied to IC neurons, which were monitored for changes in their responses to auditory stimuli. Different agonists had different effects on neural responses. The 5-HT1A agonist had mixed facilitatory and depressive effects, whereas 5-HT1B and 5-HT2C agonists were both largely facilitatory. Different agonists changed threshold and frequency tuning in ways that reflected their effects on spike count. When pairs of agonists were applied sequentially to the same neurons, selective agonists sometimes affected neurons in ways that were similar to serotonin, but not to other selective agonists tested. Different agonists also differentially affected groups of neurons classified by the shapes of their frequency-tuning curves, with serotonin and the 5-HT1 receptors affecting proportionally more non-V-type neurons relative to the other agonists tested. In all, evidence suggests that the diversity of serotonin receptor subtypes in the IC is likely to account for at least some of the variability of the effects of serotonin and that receptor subtypes fulfill specialized roles in auditory processing. PMID:16870843

  15. The serotonin releaser fenfluramine alters the auditory responses of inferior colliculus neurons.

    PubMed

    Hall, Ian C; Hurley, Laura M

    2007-06-01

    Local direct application of the neuromodulator serotonin strongly influences auditory response properties of neurons in the inferior colliculus (IC), but endogenous stores of serotonin may be released in a distinct spatial or temporal pattern. To explore this issue, the serotonin releaser fenfluramine was iontophoretically applied to extracellularly recorded neurons in the IC of the Mexican free-tailed bat (Tadarida brasiliensis). Fenfluramine mimicked the effects of serotonin on spike count and first spike latency in most neurons, and its effects could be blocked by co-application of serotonin receptor antagonists, consistent with fenfluramine-evoked serotonin release. Responses to fenfluramine did not vary during single applications or across multiple applications, suggesting that fenfluramine did not deplete serotonin stores. A predicted gradient in the effects of fenfluramine with serotonin fiber density was not observed, but neurons with fenfluramine-evoked increases in latency occurred at relatively greater recording depths compared to other neurons with similar characteristic frequencies. These findings support the conclusion that there may be spatial differences in the effects of exogenous and endogenous sources of serotonin, but that other factors such as the identities and locations of serotonin receptors are also likely to play a role in determining the dynamics of serotonergic effects. PMID:17339086

  16. Decreased norepinephrine (NE) uptake in cerebral cortex and inferior colliculus of genetically epilepsy prone (GEP) rats

    SciTech Connect

    Browning, R.A.; Rigler-Daugherty, S.K.; Long, G.; Jobe, P.C.; Wade, D.R.

    1986-03-01

    GEP rats are characterized by an enhanced susceptibility to seizures caused by a variety of stimuli, most notably sound. Pharmacological treatments that reduce the synaptic concentration of NE increase seizure severity in GEP rats while elevations in NE have the opposite effect. GEP rats also display a widespread deficit in brain NE concentration suggesting that their increased seizure susceptibility is related to a deficit in noradrenergic transmission. The authors have compared the kinetics of /sup 3/H-NE uptake in the P/sub 2/ synaptosomal fraction isolated from the cerebral cortex of normal and GEP-rats. Although the apparent Kms were not significantly different (Normal +/- SEM:0.37 +/- 0.13..mu..M; GEP +/- SEM: 0.29 +/- 0.07..mu..M), the Vmax for GEP rats was 48% lower than that of normal rats (Normal +/- SEM: 474 +/- 45 fmole/mg/4min; GEP +/- SEM: 248 +/- 16 fmole/mg/4min). Because of the possible role of the inferior colliculus (IC) in the initiation of sound-induced seizures in GEP rats, the authors measured synaptosomal NE uptake in the IC using a NE concentration of 50 nM. The IC synaptosomal NE uptake was found to be 35% lower in GEP than in normal rats. These findings are consistent with the hypothesis that a deficit in noradrenergic transmission is related to the increased seizure susceptibility of GEP rats.

  17. Neuronal morphology in subdivisions of the inferior colliculus of chicken (Gallus gallus).

    PubMed

    Niederleitner, Bertram; Luksch, Harald

    2012-05-01

    The avian inferior colliculus (IC), also referred to as the nucleus mesencephalicus lateralis pars dorsalis (MLd), is an auditory midbrain nucleus that converges auditory cues from tonotopically organized brainstem nuclei. This information is relayed onto the optic tectum on the one hand and to nucleus ovoidalis on the other hand. Morphologically, there has been considerable debate about the number and nomenclature of the subnuclei within the IC. Here, we provide morphological characteristics of single cells in five IC subnuclei in chicken. The cellular structure within the IC was studied by whole-cell patch technique and biocytin iontophoresis. In addition, histological staining was performed, to delineate the borders between subnuclei of the IC. We were able to discriminate between 5 subnuclei: the core of the central nucleus (ICCc), the medial and lateral shell of the central nucleus (ICCms and ICCls), the external nucleus (ICX) and the superficial nucleus (ICS) of the IC. Our findings suggest the existence of at least two different morphologies of neurons with two subtypes each. The IC in chicken is a largely homogenous nucleus in terms of neuronal anatomy on a cellular level. However, its compartmentation into diversified subnuclei with different neurophysiological characteristics suggests a complex system to process auditory information. The auditory system in chicken is not as hypertrophied as in specialists such as the barn owl, but appears to have comparable connectivity and cellular morphology. PMID:22525356

  18. Excitatory, inhibitory and facilitatory frequency response areas in the inferior colliculus of hearing impaired mice.

    PubMed

    Felix, Richard A; Portfors, Christine V

    2007-06-01

    Individuals with age-related hearing loss often have difficulty understanding complex sounds such as basic speech. The C57BL/6 mouse suffers from progressive sensorineural hearing loss and thus is an effective tool for dissecting the neural mechanisms underlying changes in complex sound processing observed in humans. Neural mechanisms important for processing complex sounds include multiple tuning and combination sensitivity, and these responses are common in the inferior colliculus (IC) of normal hearing mice. We examined neural responses in the IC of C57Bl/6 mice to single and combinations of tones to examine the extent of spectral integration in the IC after age-related high frequency hearing loss. Ten percent of the neurons were tuned to multiple frequency bands and an additional 10% displayed non-linear facilitation to the combination of two different tones (combination sensitivity). No combination-sensitive inhibition was observed. By comparing these findings to spectral integration properties in the IC of normal hearing CBA/CaJ mice, we suggest that high frequency hearing loss affects some of the neural mechanisms in the IC that underlie the processing of complex sounds. The loss of spectral integration properties in the IC during aging likely impairs the central auditory system's ability to process complex sounds such as speech. PMID:17412539

  19. Development of hyperactivity after acoustic trauma in the guinea pig inferior colliculus.

    PubMed

    Mulders, W H A M; Robertson, D

    2013-04-01

    The time of onset of hyperactivity (increased spontaneous firing rates) was investigated by single neuron recording in the inferior colliculus (IC) of guinea pigs subjected to unilateral acoustic trauma (exposure to a loud 10 kHz tone). Hyperactivity was present by 12 h post acoustic trauma whereas data obtained within approximately 4 h of the cessation of acoustic trauma found no evidence of hyperactivity. These data suggest that hyperactivity in the IC begins at some time between 4 and 12 h post trauma and is a relatively rapid plastic event beginning within hours rather than days post cochlear trauma. This is consistent with results reported in the cat auditory cortex (Norena and Eggermont, 2003). Hyperactivity did not show any further systematic increase between 12 h and up to 2 weeks post acoustic trauma. At recovery times of 12 and 24 h hyperactivity was widespread across most regions of the IC but at longer recovery times, it became progressively more restricted to ventral regions corresponding to the regions of the cochlea where there was persistent damage. PMID:23276730

  20. First spike latency code for interaural phase difference discrimination in the guinea pig inferior colliculus.

    PubMed

    Zohar, Oran; Shackleton, Trevor M; Nelken, Israel; Palmer, Alan R; Shamir, Maoz

    2011-06-22

    First spike latency has been suggested as a source of the information required for fast discrimination tasks. However, the accuracy of such a mechanism has not been analyzed rigorously. Here, we investigate the utility of first spike latency for encoding information about the location of a sound source, based on the responses of inferior colliculus (IC) neurons in the guinea pig to interaural phase differences (IPDs). First spike latencies of many cells in the guinea pig IC show unimodal tuning to stimulus IPD. We investigated the discrimination accuracy of a simple latency code that estimates stimulus IPD from the preferred IPD of the single cell that fired first. Surprisingly, despite being based on only a single spike, the accuracy of the latency code is comparable to that of a conventional rate code computed over the entire response. We show that spontaneous firing limits the capacity of the latency code to accumulate information from large neural populations. This detrimental effect can be overcome by generalizing the latency code to estimate the stimulus IPD from the preferred IPDs of the population of cells that fired the first n spikes. In addition, we show that a good estimate of the neural response time to the stimulus, which can be obtained from the responses of the cells whose response latency is invariant to stimulus identity, limits the detrimental effect of spontaneous firing. Thus, a latency code may provide great improvement in response speed at a small cost to the accuracy of the decision. PMID:21697370

  1. A function for binaural integration in auditory grouping and segregation in the inferior colliculus.

    PubMed

    Nakamoto, Kyle T; Shackleton, Trevor M; Magezi, David A; Palmer, Alan R

    2015-03-15

    Responses of neurons to binaural, harmonic complex stimuli in urethane-anesthetized guinea pig inferior colliculus (IC) are reported. To assess the binaural integration of harmonicity cues for sound segregation and grouping, responses were measured to harmonic complexes with different fundamental frequencies presented to each ear. Simultaneously gated harmonic stimuli with fundamental frequencies of 125 Hz and 145 Hz were presented to the left and right ears, respectively, and recordings made from 96 neurons with characteristic frequencies >2 kHz in the central nucleus of the IC. Of these units, 70 responded continuously throughout the stimulus and were excited by the stimulus at the contralateral ear. The stimulus at the ipsilateral ear excited (EE: 14%; 10/70), inhibited (EI: 33%; 23/70), or had no significant effect (EO: 53%; 37/70), defined by the effect on firing rate. The neurons phase locked to the temporal envelope at each ear to varying degrees depending on signal level. Many of the cells (predominantly EO) were dominated by the response to the contralateral stimulus. Another group (predominantly EI) synchronized to the contralateral stimulus and were suppressed by the ipsilateral stimulus in a phasic manner. A third group synchronized to the stimuli at both ears (predominantly EE). Finally, a group only responded when the waveform peaks from each ear coincided. We conclude that these groups of neurons represent different "streams" of information but exhibit modifications of the response rather than encoding a feature of the stimulus, like pitch. PMID:25540219

  2. Sodium salicylate reduces the level of GABAB receptors in the rat's inferior colliculus.

    PubMed

    Butt, S; Ashraf, F; Porter, L A; Zhang, H

    2016-03-01

    Previous studies have indicated that sodium salicylate (SS) can cause hearing abnormalities through affecting the central auditory system. In order to understand central effects of the drug, we examined how a single intraperitoneal injection of the drug changed the level of subunits of the type-B γ-aminobutyric acid receptor (GABAB receptor) in the rat's inferior colliculus (IC). Immunohistochemical and western blotting experiments were conducted three hours following a drug injection, as previous studies indicated that a tinnitus-like behavior could be reliably induced in rats within this time period. Results revealed that both subunits of the receptor, GABABR1 and GABABR2, reduced their level over the entire area of the IC. Such a reduction was observed in both cell body and neuropil regions. In contrast, no changes were observed in other brain structures such as the cerebellum. Thus, a coincidence existed between a structure-specific reduction in the level of GABAB receptor subunits in the IC and the presence of a tinnitus-like behavior. This coincidence likely suggests that a reduction in the level of GABAB receptor subunits was involved in the generation of a tinnitus-like behavior and/or used by the nervous system to restore normal hearing following application of SS. PMID:26705739

  3. Preservation of spectrotemporal tuning between the nucleus laminaris and the inferior colliculus of the barn owl.

    PubMed

    Christianson, G Björn; Peña, José Luis

    2007-05-01

    Performing sound recognition is a task that requires an encoding of the time-varying spectral structure of the auditory stimulus. Similarly, computation of the interaural time difference (ITD) requires knowledge of the precise timing of the stimulus. Consistent with this, low-level nuclei of birds and mammals implicated in ITD processing encode the ongoing phase of a stimulus. However, the brain areas that follow the binaural convergence for the computation of ITD show a reduced capacity for phase locking. In addition, we have shown that in the barn owl there is a pooling of ITD-responsive neurons to improve the reliability of ITD coding. Here we demonstrate that despite two stages of convergence and an effective loss of phase information, the auditory system of the anesthetized barn owl displays a graceful transition to an envelope coding that preserves the spectrotemporal information throughout the ITD pathway to the neurons of the core of the central nucleus of the inferior colliculus. PMID:17314241

  4. Noise reduction of coincidence detector output by the inferior colliculus of the barn owl.

    PubMed

    Christianson, G Björn; Peña, José Luis

    2006-05-31

    A recurring theme in theoretical work is that integration over populations of similarly tuned neurons can reduce neural noise. However, there are relatively few demonstrations of an explicit noise reduction mechanism in a neural network. Here we demonstrate that the brainstem of the barn owl includes a stage of processing apparently devoted to increasing the signal-to-noise ratio in the encoding of the interaural time difference (ITD), one of two primary binaural cues used to compute the position of a sound source in space. In the barn owl, the ITD is processed in a dedicated neural pathway that terminates at the core of the inferior colliculus (ICcc). The actual locus of the computation of the ITD is before ICcc in the nucleus laminaris (NL), and ICcc receives no inputs carrying information that did not originate in NL. Unlike in NL, the rate-ITD functions of ICcc neurons require as little as a single stimulus presentation per ITD to show coherent ITD tuning. ICcc neurons also displayed a greater dynamic range with a maximal difference in ITD response rates approximately double that seen in NL. These results indicate that ICcc neurons perform a computation functionally analogous to averaging across a population of similarly tuned NL neurons. PMID:16738236

  5. Inhibition sensitive to interaural time difference in the barn owl's inferior colliculus.

    PubMed

    Albeck, Y

    1997-07-01

    In spontaneously active neurons in the external nucleus of the inferior colliculus of the barn owl, a stimulus-driven discharge was followed by a quiescent period lasting tens of milliseconds before the spontaneous activity resumed. The more favorable the interaural time difference, the longer the quiet period. The duration of the quiescent period also depended on stimulus frequency. Frequencies different from the neuron's best frequency induced shorter quiescent periods, although they could elicit similar rates of impulses. Also, the duration of the quiescent period was independent of interaural intensity difference. Thus, the quiet period is not due to an after-hyperpolarization but was an inhibitory effect that depended on the activity of other neurons. In some neurons, discharge continued after the stimulus without a quiescent period and gradually decayed over a period of 50-100 ms past the stimulus offset. The similarity between the quiescent period of the neurons mentioned above and the time course of the poststimulus discharge in these neurons suggests that these neurons serve as inhibitory interneurons. PMID:9259240

  6. Human inferior colliculus activity relates to individual differences in spoken language learning

    PubMed Central

    Chandrasekaran, Bharath; Kraus, Nina

    2012-01-01

    A challenge to learning words of a foreign language is encoding nonnative phonemes, a process typically attributed to cortical circuitry. Using multimodal imaging methods [functional magnetic resonance imaging-adaptation (fMRI-A) and auditory brain stem responses (ABR)], we examined the extent to which pretraining pitch encoding in the inferior colliculus (IC), a primary midbrain structure, related to individual variability in learning to successfully use nonnative pitch patterns to distinguish words in American English-speaking adults. fMRI-A indexed the efficiency of pitch representation localized to the IC, whereas ABR quantified midbrain pitch-related activity with millisecond precision. In line with neural “sharpening” models, we found that efficient IC pitch pattern representation (indexed by fMRI) related to superior neural representation of pitch patterns (indexed by ABR), and consequently more successful word learning following sound-to-meaning training. Our results establish a critical role for the IC in speech-sound representation, consistent with the established role for the IC in the representation of communication signals in other animal models. PMID:22131377

  7. Development of hyperactivity after acoustic trauma in the guinea pig inferior colliculus.

    PubMed

    Mulders, W H A M; Robertson, D

    2013-04-01

    The time of onset of hyperactivity (increased spontaneous firing rates) was investigated by single neuron recording in the inferior colliculus (IC) of guinea pigs subjected to unilateral acoustic trauma (exposure to a loud 10 kHz tone). Hyperactivity was present by 12 h post acoustic trauma whereas data obtained within approximately 4 h of the cessation of acoustic trauma found no evidence of hyperactivity. These data suggest that hyperactivity in the IC begins at some time between 4 and 12 h post trauma and is a relatively rapid plastic event beginning within hours rather than days post cochlear trauma. This is consistent with results reported in the cat auditory cortex (Norena and Eggermont, 2003). Hyperactivity did not show any further systematic increase between 12 h and up to 2 weeks post acoustic trauma. At recovery times of 12 and 24 h hyperactivity was widespread across most regions of the IC but at longer recovery times, it became progressively more restricted to ventral regions corresponding to the regions of the cochlea where there was persistent damage.

  8. Transient Gain Adjustment in the Inferior Colliculus is Serotonin- and Calcium-dependent

    PubMed Central

    Miko, Ilona J.; Sanes, Dan H.

    2009-01-01

    In the inferior colliculus (IC), a brief period of acoustic conditioning can transiently enhance evoked discharge rate. The cellular basis of this phenomenon was assessed with whole cell current-clamp recordings in a gerbil IC brain slice preparation. The current needed to elicit a single action potential was first established for each neuron. A 5s synaptic stimulus train was delivered to the lateral lemniscus (LL), and followed immediately by the initial current pulse to assess a change in postsynaptic gain. The majority of IC neurons (66%) displayed an increase in current-evoked action potentials (positive gain). Despite the blockade of ionotropic glutamate receptors, this effect was correlated with membrane depolarization that occurred during the synaptic train. The postsynaptic mechanism for positive gain was examined by selective blockade of specific neurotransmitter receptors. Gain in action potentials was enhanced by antagonists of metabotropic glutamate, acetylcholine, GABAA and glycine receptors. In contrast, the gain was blocked or reduced by an antagonist to ionotropic serotonin receptors (5-HT3R). Blocking voltage-activated calcium channels with verapamil also reduced the effect. These results suggest that 5-HT3R activation, coupled with increased intracellular calcium, can transiently alter postsynaptic excitability in IC neurons. PMID:19232535

  9. Excitatory and facilitatory frequency response areas in the inferior colliculus of the mustached bat.

    PubMed

    Portfors, Christine V; Wenstrup, Jeffrey J

    2002-06-01

    In the mustached bat's central nucleus of the inferior colliculus (ICC), many neurons display facilitatory or inhibitory responses when presented with two tones of distinctly different frequencies. Our previous studies have focused on spectral interactions between specific frequency bands contained in the bat's sonar vocalization. In this study, we describe excitatory and facilitatory frequency response areas across all frequencies in the mustached bat's audible range. We show that many neurons in the ICC have more extensive frequency interactions than previously documented. We recorded responses of 96 single units to single tones and combinations of two tones. Best frequencies of the units ranged from 59-15 kHz. Forty-one units had a single, excitatory frequency response area. The rest of the units had more complex frequency tuning that included multiple excitatory frequency response areas and facilitatory frequency response areas. Some of the facilitatory frequency interactions were between one sound with energy in a sonar frequency band and a second sound with energy in a non-sonar frequency band. We also found that neurons could be facilitated by more than one additional frequency band. Our findings of extensive frequency interactions in the ICC of the mustached bat suggest that some neurons may be well suited for the analysis of complex sounds, possibly including social communication sounds.

  10. FM signals produce robust paradoxical latency shifts in the bat's inferior colliculus.

    PubMed

    Wang, Xinming; Galazyuk, Alexander V; Feng, Albert S

    2007-01-01

    Previous studies in echolocating bats, Myotis lucifugus, showed that paradoxical latency shift (PLS) is essential for neural computation of target range and that a number of neurons in the inferior colliculus (IC) exhibit unit-specific PLS (characterized by longer first-spike latency at higher sound levels) in response to tone pulses at the unit's best frequency. The present study investigated whether or not frequency-modulated (FM) pulses that mimic the bat's echolocation sonar signals were equally effective in eliciting PLS. For two-thirds of PLS neurons in the IC, both FM and tone pulses could elicit PLS, but only FM pulses consistently produced unit-specific PLS. For the remainder of PLS neurons, only FM pulses effectively elicited PLS; these cells showed either no PLS or no response, to tone pulses. PLS neurons generally showed more pronounced PLS in response to narrow-band FM (each sweeping 20 kHz in 2 ms) pulse that contained the unit's best frequency. In addition, almost all PLS neurons showed duration-independent PLS to FM pulses, but the same units exhibited duration-dependent PLS to tone pulses. Taken together, when compared to tone pulses, FM stimuli can provide more reliable estimates of target range.

  11. Negative temporal summation of the responses to pairs of tone bursts in albino mice inferior colliculus

    NASA Astrophysics Data System (ADS)

    Bibikov, Nikolay G.; Cai, Chen Qi; Jie, Tang

    2003-10-01

    The extracellular activities of single units in an inferior colliculus of narcotized albino mice have been studied. As a stimuli pairs of best frequency (BF) tone bursts with different duration have been used and forward masking has been studied. The test tone usually has a 40 ms duration at intensity 5 dB above threshold. The intensity and duration of the masker could be changed. It was shown that the forward masking essentially depends upon the duration of the first burst. In many cases, the negative temporal summation can be seen. The increase in the duration of first burst (or masker) leads to the decrease in the whole response. Moreover, the BF tone burst which did not evoke any spike response could inhibit the response to the second (test) tone in some cases. Therefore in many units the inhibitory threshold was lower than the excitatory threshold even at the best frequency. The local application of bicuculline through a multibarrel-electrode increased the pulse activity considerably. However, the effect of forward masking usually left even after an inhibitory antagonist (bicuculline) application. [Work supported by grants 39970251 from NSFC, T010360056 from the Foreign Expert Bureau of the State Council of China, and 02-04-3900 from RFBR-NSFC.

  12. Spread of cochlear excitation during stimulation with pulsed infrared radiation: inferior colliculus measurements

    NASA Astrophysics Data System (ADS)

    Richter, C.-P.; Rajguru, S. M.; Matic, A. I.; Moreno, E. L.; Fishman, A. J.; Robinson, A. M.; Suh, E.; Walsh, J. T., Jr.

    2011-10-01

    Infrared neural stimulation (INS) has received considerable attention over the last few years. It provides an alternative method to artificially stimulate neurons without electrical current or the introduction of exogenous chromophores. One of the primary benefits of INS could be the improved spatial selectivity when compared with electrical stimulation. In the present study, we have evaluated the spatial selectivity of INS in the acutely damaged cochlea of guinea pigs and compared it to stimulation with acoustic tone pips in normal-hearing animals. The radiation was delivered via a 200 µm diameter optical fiber, which was inserted through a cochleostomy into the scala tympani of the basal cochlear turn. The stimulated section along the cochlear spiral ganglion was estimated from the neural responses recorded from the central nucleus of the inferior colliculus (ICC). ICC responses were recorded in response to cochlear INS using a multichannel penetrating electrode array. Spatial tuning curves (STCs) were constructed from the responses. For INS, approximately 55% of the activation profiles showed a single maximum, ~22% had two maxima and ~13% had multiple maxima. The remaining 10% of the profiles occurred at the limits of the electrode array and could not be classified. The majority of ICC STCs indicated that the spread of activation evoked by optical stimuli is comparable to that produced by acoustic tone pips.

  13. Age-related neurochemical changes in the rhesus macaque inferior colliculus

    PubMed Central

    Engle, James R.; Gray, Daniel T.; Turner, Heather; Udell, Julia B.; Recanzone, Gregg H.

    2014-01-01

    Age-related hearing loss (ARHL) is marked by audiometric hearing deficits that propagate along the auditory pathway. Neurochemical changes as a function of aging have also been identified in neurons along the auditory pathway in both rodents and carnivores, however, very little is known about how these neurochemicals change in the non-human primate. To examine how these compensatory neurochemical changes relate to normal aging and audiometric sensitivity along the auditory pathway, we collected auditory brainstem responses (ABRs) and brain specimens from seven rhesus monkeys spanning in age from 15 to 35 years old, and examined the relationship between click evoked ABR thresholds and the ABR evoked pure tone average (PTA) and changes in the number of parvalbumin and NADPH-diaphorase positive cells in the auditory midbrain. We found that the number of parvalbumin positive cells in the central nucleus and the surrounding cortex regions of the inferior colliculus were strongly correlated with advancing age and ABR PTA. We also found that the numbers of NADPHd positive cells in these same regions were not associated with normal aging or changes in the ABR thresholds. These findings suggest that the auditory midbrain undergoes an up-regulation of parvalbumin expressing neurons with aging that is related to changes in the processing of frequencies across the audiometric range. PMID:24795627

  14. Inhibition shapes selectivity to vocalizations in the inferior colliculus of awake mice

    PubMed Central

    Mayko, Zachary M.; Roberts, Patrick D.; Portfors, Christine V.

    2012-01-01

    The inferior colliculus (IC) is a major center for integration of auditory information as it receives ascending projections from a variety of brainstem nuclei as well as descending projections from the thalamus and auditory cortex. The ascending projections are both excitatory and inhibitory and their convergence at the IC results in a microcircuitry that is important for shaping responses to simple, binaural, and modulated sounds in the IC. Here, we examined the role inhibition plays in shaping selectivity to vocalizations in the IC of awake, normal-hearing adult mice (CBA/CaJ strain). Neurons in the IC of mice show selectivity in their responses to vocalizations, and we hypothesized that this selectivity is created by inhibitory microcircuitry in the IC. We compared single unit responses in the IC to pure tones and a variety of ultrasonic mouse vocalizations before and after iontophoretic application of GABAA receptor (GABAAR) and glycine receptor (GlyR) antagonists. The most pronounced effects of blocking GABAAR and GlyR on IC neurons were to increase spike rates and broaden excitatory frequency tuning curves in response to pure tone stimuli, and to decrease selectivity to vocalizations. Thus, inhibition plays an important role in creating selectivity to vocalizations in the IC. PMID:23087616

  15. Periodotopy in the gerbil inferior colliculus: local clustering rather than a gradient map

    PubMed Central

    Schnupp, Jan W. H.; Garcia-Lazaro, Jose A.; Lesica, Nicholas A.

    2015-01-01

    Periodicities in sound waveforms are widespread, and shape important perceptual attributes of sound including rhythm and pitch. Previous studies have indicated that, in the inferior colliculus (IC), a key processing stage in the auditory midbrain, neurons tuned to different periodicities might be arranged along a periodotopic axis which runs approximately orthogonal to the tonotopic axis. Here we map out the topography of frequency and periodicity tuning in the IC of gerbils in unprecedented detail, using pure tones and different periodic sounds, including click trains, sinusoidally amplitude modulated (SAM) noise and iterated rippled noise. We found that while the tonotopic map exhibited a clear and highly reproducible gradient across all animals, periodotopic maps varied greatly across different types of periodic sound and from animal to animal. Furthermore, periodotopic gradients typically explained only about 10% of the variance in modulation tuning between recording sites. However, there was a strong local clustering of periodicity tuning at a spatial scale of ca. 0.5 mm, which also differed from animal to animal. PMID:26379508

  16. Dynamic temporal signal processing in the inferior colliculus of echolocating bats

    PubMed Central

    Jen, Philip H.-S.; Wu, Chung Hsin; Wang, Xin

    2012-01-01

    In nature, communication sounds among animal species including humans are typical complex sounds that occur in sequence and vary with time in several parameters including amplitude, frequency, duration as well as separation, and order of individual sounds. Among these multiple parameters, sound duration is a simple but important one that contributes to the distinct spectral and temporal attributes of individual biological sounds. Likewise, the separation of individual sounds is an important temporal attribute that determines an animal's ability in distinguishing individual sounds. Whereas duration selectivity of auditory neurons underlies an animal's ability in recognition of sound duration, the recovery cycle of auditory neurons determines a neuron's ability in responding to closely spaced sound pulses and therefore, it underlies the animal's ability in analyzing the order of individual sounds. Since the multiple parameters of naturally occurring communication sounds vary with time, the analysis of a specific sound parameter by an animal would be inevitably affected by other co-varying sound parameters. This is particularly obvious in insectivorous bats, which rely on analysis of returning echoes for prey capture when they systematically vary the multiple pulse parameters throughout a target approach sequence. In this review article, we present our studies of dynamic variation of duration selectivity and recovery cycle of neurons in the central nucleus of the inferior colliculus of the frequency-modulated bats to highlight the dynamic temporal signal processing of central auditory neurons. These studies use single pulses and three biologically relevant pulse-echo (P-E) pairs with varied duration, gap, and amplitude difference similar to that occurring during search, approach, and terminal phases of hunting by bats. These studies show that most collicular neurons respond maximally to a best tuned sound duration (BD). The sound duration to which these neurons are

  17. Excitatory and inhibitory projections in parallel pathways from the inferior colliculus to the auditory thalamus.

    PubMed

    Mellott, Jeffrey G; Foster, Nichole L; Ohl, Andrew P; Schofield, Brett R

    2014-01-01

    Individual subdivisions of the medial geniculate body (MG) receive a majority of their ascending inputs from 1 or 2 subdivisions of the inferior colliculus (IC). This establishes parallel pathways that provide a model for understanding auditory projections from the IC through the MG and on to auditory cortex. A striking discovery about the tectothalamic circuit was identification of a substantial GABAergic component. Whether GABAergic projections match the parallel pathway organization has not been examined. We asked whether the parallel pathway concept is reflected in guinea pig tectothalamic pathways and to what degree GABAergic cells contribute to each pathway. We deposited retrograde tracers into individual MG subdivisions (ventral, MGv; medial, MGm; dorsal, MGd; suprageniculate, MGsg) to label tectothalamic cells and used immunochemistry to identify GABAergic cells. The MGv receives most of its IC input (~75%) from the IC central nucleus (ICc); MGd and MGsg receive most of their input (~70%) from IC dorsal cortex (ICd); and MGm receives substantial input from both ICc (~40%) and IC lateral cortex (~40%). Each MG subdivision receives additional input (up to 32%) from non-dominant IC subdivisions, suggesting cross-talk between the pathways. The proportion of GABAergic cells in each pathway depended on the MG subdivision. GABAergic cells formed ~20% of IC inputs to MGv or MGm, ~11% of inputs to MGd, and 4% of inputs to MGsg. Thus, non-GABAergic (i.e., glutamatergic) cells are most numerous in each pathway with GABAergic cells contributing to different extents. Despite smaller numbers of GABAergic cells, their distributions across IC subdivisions mimicked the parallel pathways. Projections outside the dominant pathways suggest opportunities for excitatory and inhibitory crosstalk. The results demonstrate parallel tectothalamic pathways in guinea pigs and suggest numerous opportunities for excitatory and inhibitory interactions within and between pathways.

  18. The representation of sound localization cues in the barn owl's inferior colliculus.

    PubMed

    Singheiser, Martin; Gutfreund, Yoram; Wagner, Hermann

    2012-01-01

    The barn owl is a well-known model system for studying auditory processing and sound localization. This article reviews the morphological and functional organization, as well as the role of the underlying microcircuits, of the barn owl's inferior colliculus (IC). We focus on the processing of frequency and interaural time (ITD) and level differences (ILD). We first summarize the morphology of the sub-nuclei belonging to the IC and their differentiation by antero- and retrograde labeling and by staining with various antibodies. We then focus on the response properties of neurons in the three major sub-nuclei of IC [core of the central nucleus of the IC (ICCc), lateral shell of the central nucleus of the IC (ICCls), and the external nucleus of the IC (ICX)]. ICCc projects to ICCls, which in turn sends its information to ICX. The responses of neurons in ICCc are sensitive to changes in ITD but not to changes in ILD. The distribution of ITD sensitivity with frequency in ICCc can only partly be explained by optimal coding. We continue with the tuning properties of ICCls neurons, the first station in the midbrain where the ITD and ILD pathways merge after they have split at the level of the cochlear nucleus. The ICCc and ICCls share similar ITD and frequency tuning. By contrast, ICCls shows sigmoidal ILD tuning which is absent in ICCc. Both ICCc and ICCls project to the forebrain, and ICCls also projects to ICX, where space-specific neurons are found. Space-specific neurons exhibit side peak suppression in ITD tuning, bell-shaped ILD tuning, and are broadly tuned to frequency. These neurons respond only to restricted positions of auditory space and form a map of two-dimensional auditory space. Finally, we briefly review major IC features, including multiplication-like computations, correlates of echo suppression, plasticity, and adaptation. PMID:22798945

  19. Classification of frequency response areas in the inferior colliculus reveals continua not discrete classes.

    PubMed

    Palmer, Alan R; Shackleton, Trevor M; Sumner, Christian J; Zobay, Oliver; Rees, Adrian

    2013-08-15

    A differential response to sound frequency is a fundamental property of auditory neurons. Frequency analysis in the cochlea gives rise to V-shaped tuning functions in auditory nerve fibres, but by the level of the inferior colliculus (IC), the midbrain nucleus of the auditory pathway, neuronal receptive fields display diverse shapes that reflect the interplay of excitation and inhibition. The origin and nature of these frequency receptive field types is still open to question. One proposed hypothesis is that the frequency response class of any given neuron in the IC is predominantly inherited from one of three major afferent pathways projecting to the IC, giving rise to three distinct receptive field classes. Here, we applied subjective classification, principal component analysis, cluster analysis, and other objective statistical measures, to a large population (2826) of frequency response areas from single neurons recorded in the IC of the anaesthetised guinea pig. Subjectively, we recognised seven frequency response classes (V-shaped, non-monotonic Vs, narrow, closed, tilt down, tilt up and double-peaked), that were represented at all frequencies. We could identify similar classes using our objective classification tools. Importantly, however, many neurons exhibited properties intermediate between these classes, and none of the objective methods used here showed evidence of discrete response classes. Thus receptive field shapes in the IC form continua rather than discrete classes, a finding consistent with the integration of afferent inputs in the generation of frequency response areas. The frequency disposition of inhibition in the response areas of some neurons suggests that across-frequency inputs originating at or below the level of the IC are involved in their generation. PMID:23753527

  20. Descending and tonotopic projection patterns from the auditory cortex to the inferior colliculus.

    PubMed

    Straka, M M; Hughes, R; Lee, P; Lim, H H

    2015-08-01

    The inferior colliculus (IC) receives many corticofugal projections, which can mediate plastic changes such as shifts in frequency tuning or excitability of IC neurons. While the densest projections are found in the IC's external cortices, fibers originating from the primary auditory cortex (AI) have been observed throughout the IC's central nucleus (ICC), and these projections have shown to be organized tonotopically. Some studies have also found projections from other core and non-core cortical regions, though the organization and function of these projections are less known. In guinea pig, there exists a non-core ventrorostral belt (VRB) region that has primary-like properties and has often been mistaken for AI, with the clearest differentiating characteristic being VRB's longer response latencies. To better understand the auditory corticofugal descending system beyond AI, we investigated if there are projections from VRB to the ICC and if they exhibit a different projection pattern than those from AI. In this study, we performed experiments in ketamine-anesthetized guinea pigs, in which we positioned 32-site electrode arrays within AI, VRB, and ICC. We identified the monosynaptic connections between AI-to-ICC and VRB-to-ICC using an antidromic stimulation method, and we analyzed their locations across the midbrain using three-dimensional histological techniques. Compared to the corticocollicular projections to the ICC from AI, there were fewer projections to the ICC from VRB, and these projections had a weaker tonotopic organization. The majority of VRB projections were observed in the caudal-medial versus the rostral-lateral region along an isofrequency lamina of the ICC, which is in contrast to the AI projections that were scattered throughout an ICC lamina. These findings suggest that the VRB directly modulates sound information within the ascending lemniscal pathway with a different or complementary role compared to the modulatory effects of AI, which may

  1. A Computational Model of Inferior Colliculus Responses to Amplitude Modulated Sounds in Young and Aged Rats

    PubMed Central

    Rabang, Cal F.; Parthasarathy, Aravindakshan; Venkataraman, Yamini; Fisher, Zachery L.; Gardner, Stephanie M.; Bartlett, Edward L.

    2012-01-01

    The inferior colliculus (IC) receives ascending excitatory and inhibitory inputs from multiple sources, but how these auditory inputs converge to generate IC spike patterns is poorly understood. Simulating patterns of in vivo spike train data from cellular and synaptic models creates a powerful framework to identify factors that contribute to changes in IC responses, such as those resulting in age-related loss of temporal processing. A conductance-based single neuron IC model was constructed, and its responses were compared to those observed during in vivo IC recordings in rats. IC spike patterns were evoked using amplitude-modulated tone or noise carriers at 20–40 dB above threshold and were classified as low-pass, band-pass, band-reject, all-pass, or complex based on their rate modulation transfer function tuning shape. Their temporal modulation transfer functions were also measured. These spike patterns provided experimental measures of rate, vector strength, and firing pattern for comparison with model outputs. Patterns of excitatory and inhibitory synaptic convergence to IC neurons were based on anatomical studies and generalized input tuning for modulation frequency. Responses of modeled ascending inputs were derived from experimental data from previous studies. Adapting and sustained IC intrinsic models were created, with adaptation created via calcium-activated potassium currents. Short-term synaptic plasticity was incorporated into the model in the form of synaptic depression, which was shown to have a substantial effect on the magnitude and time course of the IC response. The most commonly observed IC response sub-types were recreated and enabled dissociation of inherited response properties from those that were generated in IC. Furthermore, the model was used to make predictions about the consequences of reduction in inhibition for age-related loss of temporal processing due to a reduction in GABA seen anatomically with age. PMID:23129994

  2. Representation of interaural time difference in the central nucleus of the barn owl's inferior colliculus.

    PubMed

    Wagner, H; Takahashi, T; Konishi, M

    1987-10-01

    This paper investigates the role of the central nucleus of the barn owl's inferior colliculus in determination of the sound-source azimuth. The central nucleus contains many neurons that are sensitive to interaural time difference (ITD), the cue for azimuth in the barn owl. The response of these neurons varies in a cyclic manner with the ITD of a tone or noise burst. Response maxima recur at integer multiples of the period of the stimulating tone, or, if the stimulus is noise, at integer multiples of the period corresponding to the neuron's best frequency. Such neurons can signal, by means of their relative spike rate, the phase difference between the sounds reaching the left and right ears. Since an interaural phase difference corresponds to more than one ITD, these neurons represent ITD ambiguously. We call this phenomenon phase ambiguity. The central nucleus is tonotopically organized and its neurons are narrowly tuned to frequency. Neurons in an array perpendicular to isofrequency laminae form a physiological and anatomical unit; only one ITD, the array-specific ITD, activates all neurons in an array at the same relative level. We, therefore, may say that, in the central nucleus, an ITD is conserved in an array of neurons. Array-specific ITDs are mapped and encompass the entire auditory space of the barn owl. Individual space-specific neurons of the external nucleus, which receive inputs from a wide range of frequency channels (Knudsen and Konishi, 1978), are selective for a unique ITD. Space-specific neurons do not show phase ambiguity when stimulated with noise (Takahashi and Konishi, 1986). Space-specific neurons receive inputs from arrays that are selective for the same ITD. The collective response of the neurons in an array may be the basis for the absence of phase ambiguity in space-specific neurons. PMID:3668618

  3. Pharmacological specialization of learned auditory responses in the inferior colliculus of the barn owl.

    PubMed

    Feldman, D E; Knudsen, E I

    1998-04-15

    Neural tuning for interaural time difference (ITD) in the optic tectum of the owl is calibrated by experience-dependent plasticity occurring in the external nucleus of the inferior colliculus (ICX). When juvenile owls are subjected to a sustained lateral displacement of the visual field by wearing prismatic spectacles, the ITD tuning of ICX neurons becomes systematically altered; ICX neurons acquire novel auditory responses, termed "learned responses," to ITD values outside their normal, pre-existing tuning range. In this study, we compared the glutamatergic pharmacology of learned responses with that of normal responses expressed by the same ICX neurons. Measurements were made in the ICX using iontophoretic application of glutamate receptor antagonists. We found that in early stages of ITD tuning adjustment, soon after learned responses had been induced by experience-dependent processes, the NMDA receptor antagonist D, L-2-amino-5-phosphonopentanoic acid (AP-5) preferentially blocked the expression of learned responses of many ICX neurons compared with that of normal responses of the same neurons. In contrast, the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) blocked learned and normal responses equally. After long periods of prism experience, preferential blockade of learned responses by AP-5 was no longer observed. These results indicate that NMDA receptors play a preferential role in the expression of learned responses soon after these responses have been induced by experience-dependent processes, whereas later in development or with additional prism experience (we cannot distinguish which), the differential NMDA receptor-mediated component of these responses disappears. This pharmacological progression resembles the changes that occur during maturation of glutamatergic synaptic currents during early development. PMID:9526024

  4. Projections of the cochlear nuclei and nucleus laminaris to the inferior colliculus of the barn owl.

    PubMed

    Takahashi, T T; Konishi, M

    1988-08-01

    The barn owl determines the directions from which sounds emanate by computing the interaural differences in the timing and intensity of sounds. These cues for sound localization are processed in independent channels originating at nucleus magnocellularis (NM) and nucleus angularis (NA), the cochlear nuclei. The cells of NM are specialized for encoding the phase of sounds in the ipsilateral ear. The cells of NA are specialized for encoding the intensity of sounds in the ipsilateral ear. NM projects solely, bilaterally, and tonotopically to nucleus laminaris (NL). NL and NA project to largely nonoverlapping zones in the central nucleus of the inferior colliculus (ICc), thus forming hodological subdivisions in which time and intensity information may be processed. The terminal field of NL occupies a discrete zone in the rostromedial portion of the contralateral ICc, which we have termed the "core" of ICc. The terminal field of NA surrounds the core of ICc and thus forms a "shell" around it. The projection from NL to the core conserves tonotopy. Low-frequency regions of NL project to the dorsal portions of the core whereas higher-frequency regions project to more ventral portions. This innervation pattern is consistent with earlier physiological studies of tonotopy. Physiological studies have also suggested that NL and the core of ICs contain a representation of the location of a sound source along the horizontal axis. Our data suggest that the projection from NL to the core preserves spatiotopy. Thus, the dorsal portion of NL on the left, which contains a representation of eccentric loci in the right hemifield, innervates the area of the right ICc core that represents eccentric right loci. The more ventral portion of the left NL, which represents loci close to the vertical meridian, innervates the more rostral portions of the right core, which also represents loci near the vertical meridian. PMID:2463286

  5. Distribution within the barn owl's inferior colliculus of neurons projecting to the optic tectum and thalamus.

    PubMed

    Arthur, Ben J

    2005-11-01

    Behavioral studies in barn owls indicate that both the optic tectum (OT) and the auditory arcopallium (AAr) mediate sound localization through the presence of neurons that respond only when sound comes from a circumscribed direction in space. The early stages of the computations leading to these so-called space-specific neurons are shared in a common brainstem pathway, which then splits at the level of the inferior colliculus (IC) such that the last computational stage is thought to be duplicated. The study presented here addresses whether the space-specific neurons in OT and AAr are indeed partially independent of each other by using anatomical methods more precise than those used in previous studies. Specifically, projection neurons in IC were retrogradely labelled with injections of fluorescein- and rhodamine-conjugated dextran amines into OT and nucleus ovoidalis (OV), the thalamic nucleus leading to AAr. By labelling the OT-projecting and OV-projecting neurons in the same owl, it was confirmed that neurons in IC project to either OV or OT but not both. However, although a segregation was generally observed between the medially positioned OV-projecting neurons and the laterally positioned OT-projecting neurons, there was also a slight overlap between the two populations. Moreover, electrolytic lesions demarcating physiological tuning properties indicate that many OV-projecting neurons are within the area containing space-specific neurons. These results highlight the need for more detailed studies elucidating the microcircuitry and corresponding physiology of IC, such as have been done in the cortices of the mammalian cerebellum and cerebrum. PMID:16175562

  6. Monaural and Binaural Inhibition Underlying Duration-Tuned Neurons in the Inferior Colliculus

    PubMed Central

    Sayegh, Riziq; Casseday, John H.; Covey, Ellen

    2014-01-01

    Duration-tuned neurons (DTNs) in the mammalian inferior colliculus (IC) arise from a combination of excitatory and inhibitory synaptic inputs. Previous research has shown that the inhibition responsible for creating DTNs has a shorter latency than that of excitation and lasts longer than the stimulus duration. We used monotic and dichotic paired tone stimulation and recorded responses of DTNs from the IC of the bat to assess the relative contributions of each ear in forming duration-tuned circuits. The stimulus consisted of a short best duration (BD) excitatory tone and a longer duration nonexcitatory (NE) tone. In the monotic condition, when the BD and NE tones were presented to the contralateral ear and were sufficiently close in time, the NE tone always suppressed spikes evoked by the BD tone. In the dichotic condition, when the BD tone was presented to the contralateral ear and the NE tone to the ipsilateral ear, half of DTNs no longer showed spike suppression to the NE tone. Of those DTNs with suppression in both conditions, the latency of the inhibition was shorter and the duration of the inhibition was longer in the monotic condition. Therefore, in the monotic condition, DTNs received a contralaterally evoked inhibitory input that preceded the excitatory input to the same neuron. In the dichotic condition, DTNs received an ipsilaterally evoked inhibitory input that was weaker, longer in latency, and shorter in duration than the inputs from the contralateral ear. These findings indicate that the neural mechanisms that create DTNs in the IC are monaural. PMID:24403148

  7. Effect of current focusing on the sensitivity of inferior colliculus neurons to amplitude-modulated stimulation.

    PubMed

    George, Shefin S; Shivdasani, Mohit N; Fallon, James B

    2016-09-01

    In multichannel cochlear implants (CIs), current is delivered to specific electrodes along the cochlea in the form of amplitude-modulated pulse trains, to convey temporal and spectral cues. Our previous studies have shown that focused multipolar (FMP) and tripolar (TP) stimulation produce more restricted neural activation and reduced channel interactions in the inferior colliculus (IC) compared with traditional monopolar (MP) stimulation, suggesting that focusing of stimulation could produce better transmission of spectral information. The present study explored the capability of IC neurons to detect modulated CI stimulation with FMP and TP stimulation compared with MP stimulation. The study examined multiunit responses of IC neurons in acutely deafened guinea pigs by systematically varying the stimulation configuration, modulation depth, and stimulation level. Stimuli were sinusoidal amplitude-modulated pulse trains (carrier rate of 120 pulses/s). Modulation sensitivity was quantified by measuring modulation detection thresholds (MDTs), defined as the lowest modulation depth required to differentiate the response of a modulated stimulus from an unmodulated one. Whereas MP stimulation showed significantly lower MDTs than FMP and TP stimulation (P values <0.05) at stimulation ≤2 dB above threshold, all stimulation configurations were found to have similar modulation sensitivities at 4 dB above threshold. There was no difference found in modulation sensitivity between FMP and TP stimulation. The present study demonstrates that current focusing techniques such as FMP and TP can adequately convey amplitude modulation and are comparable to MP stimulation, especially at higher stimulation levels, although there may be some trade-off between spectral and temporal fidelity with current focusing stimulation. PMID:27306672

  8. Erratum to "Noise-induced changes of neuronal spontaneous activity in mice inferior colliculus brain slices".

    PubMed

    Basta, Dietmar; Ernst, Arne

    2005-02-01

    The inferior colliculus (IC) in vivo is reportedly subject to a noise-induced decrease of GABA-related inhibitory synaptic transmission accompanied by an amplitude increase of auditory evoked responses, a widening of tuning curves and a higher neuronal discharge rate at suprathreshold levels. However, other in vivo experiments which demonstrated constant neuronal auditory thresholds or unchanged spontaneous activity in the IC after noise exposure did not confirm those findings. Perhaps this can be the result of complex noise-induced interactions between different central auditory structures. It was, therefore, the aim of the present study to investigate the effects of noise exposure on the spontaneous electrical activity of single neurons in a slice preparation of the isolated mouse IC. Normal hearing mice were exposed to noise (10 kHz center frequency at 115 dB SPL for 3 h) at the age of 21 days under anesthesia (Ketamin/Rompun 10:1). After one week, auditory brainstem response (ABR) recordings and extracellular single-unit recordings from spontaneously active neurons within the IC slice were performed in noise-exposed and in normal hearing control mice. Noise-exposed animals showed a significant ABR threshold shift in the whole tested frequency range and a significant lower neuronal spontaneous activity in all investigated isofrequency laminae compared to controls. In both groups, the firing rate of 80% of IC neurons (approximately) increased significantly during the application of the GABA(A) receptor antagonist Bicucullin (10 microM). The present findings demonstrate a noise-related modulation of spontaneous activity in the IC, which possibly contribute to the generation of noise-induced tinnitus and hearing loss.

  9. Noise-induced changes of neuronal spontaneous activity in mice inferior colliculus brain slices.

    PubMed

    Basta, Dietmar; Ernest, Arne

    2004-09-30

    The inferior colliculus (IC) in vivo is reportedly subject to a noise-induced decrease of GABA-related inhibitory synaptic transmission accompanied by an amplitude increase of auditory evoked responses, a widening of tuning curves and a higher neuronal discharge rate at suprathreshold levels. However, other in vivo experiments which demonstrated constant neuronal auditory thresholds or unchanged spontaneous activity in the IC after noise exposure did not confirm those findings. Perhaps this can be the result of complex noise-induced interactions between different central auditory structures. It was, therefore, the aim of the present study to investigate the effects of noise exposure on the spontaneous electrical activity of single neurons in a slice preparation of the isolated mouse IC. Normal hearing mice were exposed to noise (10 kHz center frequency at 115 dB SPL for 3 h) at the age of 21 days under anesthesia (Ketamin/Rompun 10:1). After one week, auditory brainstem response (ABR) recordings and extracellular single-unit recordings from spontaneously active neurons within the IC slice were performed in noise-exposed and in normal hearing control mice. Noise-exposed animals showed a significant ABR threshold shift in the whole tested frequency range and a significant lower neuronal spontaneous activity in all investigated isofrequency laminae compared to controls. In both groups, the firing rate of 80% of IC neurons (approximately) increased significantly during the application of the GABA(A) receptor antagonist Bicucullin (10 microM). The present findings demonstrate a noise-related modulation of spontaneous activity in the IC, which possibly contribute to the generation of noise-induced tinnitus and hearing loss.

  10. The representation of sound localization cues in the barn owl's inferior colliculus

    PubMed Central

    Singheiser, Martin; Gutfreund, Yoram; Wagner, Hermann

    2012-01-01

    The barn owl is a well-known model system for studying auditory processing and sound localization. This article reviews the morphological and functional organization, as well as the role of the underlying microcircuits, of the barn owl's inferior colliculus (IC). We focus on the processing of frequency and interaural time (ITD) and level differences (ILD). We first summarize the morphology of the sub-nuclei belonging to the IC and their differentiation by antero- and retrograde labeling and by staining with various antibodies. We then focus on the response properties of neurons in the three major sub-nuclei of IC [core of the central nucleus of the IC (ICCc), lateral shell of the central nucleus of the IC (ICCls), and the external nucleus of the IC (ICX)]. ICCc projects to ICCls, which in turn sends its information to ICX. The responses of neurons in ICCc are sensitive to changes in ITD but not to changes in ILD. The distribution of ITD sensitivity with frequency in ICCc can only partly be explained by optimal coding. We continue with the tuning properties of ICCls neurons, the first station in the midbrain where the ITD and ILD pathways merge after they have split at the level of the cochlear nucleus. The ICCc and ICCls share similar ITD and frequency tuning. By contrast, ICCls shows sigmoidal ILD tuning which is absent in ICCc. Both ICCc and ICCls project to the forebrain, and ICCls also projects to ICX, where space-specific neurons are found. Space-specific neurons exhibit side peak suppression in ITD tuning, bell-shaped ILD tuning, and are broadly tuned to frequency. These neurons respond only to restricted positions of auditory space and form a map of two-dimensional auditory space. Finally, we briefly review major IC features, including multiplication-like computations, correlates of echo suppression, plasticity, and adaptation. PMID:22798945

  11. Effect of background noise on neuronal coding of interaural level difference cues in rat inferior colliculus

    PubMed Central

    Mokri, Yasamin; Worland, Kate; Ford, Mark; Rajan, Ramesh

    2015-01-01

    Humans can accurately localize sounds even in unfavourable signal-to-noise conditions. To investigate the neural mechanisms underlying this, we studied the effect of background wide-band noise on neural sensitivity to variations in interaural level difference (ILD), the predominant cue for sound localization in azimuth for high-frequency sounds, at the characteristic frequency of cells in rat inferior colliculus (IC). Binaural noise at high levels generally resulted in suppression of responses (55.8%), but at lower levels resulted in enhancement (34.8%) as well as suppression (30.3%). When recording conditions permitted, we then examined if any binaural noise effects were related to selective noise effects at each of the two ears, which we interpreted in light of well-known differences in input type (excitation and inhibition) from each ear shaping particular forms of ILD sensitivity in the IC. At high signal-to-noise ratios (SNR), in most ILD functions (41%), the effect of background noise appeared to be due to effects on inputs from both ears, while for a large percentage (35.8%) appeared to be accounted for by effects on excitatory input. However, as SNR decreased, change in excitation became the dominant contributor to the change due to binaural background noise (63.6%). These novel findings shed light on the IC neural mechanisms for sound localization in the presence of continuous background noise. They also suggest that some effects of background noise on encoding of sound location reported to be emergent in upstream auditory areas can also be observed at the level of the midbrain. PMID:25865218

  12. Temporal features of spectral integration in the inferior colliculus: effects of stimulus duration and rise time.

    PubMed

    Gans, Donald; Sheykholeslami, Kianoush; Peterson, Diana Coomes; Wenstrup, Jeffrey

    2009-07-01

    This report examines temporal features of facilitation and suppression that underlie spectrally integrative responses to complex vocal signals. Auditory responses were recorded from 160 neurons in the inferior colliculus (IC) of awake mustached bats. Sixty-two neurons showed combination-sensitive facilitation: responses to best frequency (BF) signals were facilitated by well-timed signals at least an octave lower in frequency, in the range 16-31 kHz. Temporal features and strength of facilitation were generally unaffected by changes in duration of facilitating signals from 4 to 31 ms. Changes in stimulus rise time from 0.5 to 5.0 ms had little effect on facilitatory strength. These results suggest that low frequency facilitating inputs to high BF neurons have phasic-on temporal patterns and are responsive to stimulus rise times over the tested range. We also recorded from 98 neurons showing low-frequency (11-32 kHz) suppression of higher BF responses. Effects of changing duration were related to the frequency of suppressive signals. Signals<23 kHz usually evoked suppression sustained throughout signal duration. This and other features of such suppression are consistent with a cochlear origin that results in masking of responses to higher, near-BF signal frequencies. Signals in the 23- to 30-kHz range-frequencies in the first sonar harmonic-generally evoked phasic suppression of BF responses. This may result from neural inhibitory interactions within and below IC. In many neurons, we observed two or more forms of the spectral interactions described here. Thus IC neurons display temporally and spectrally complex responses to sound that result from multiple spectral interactions at different levels of the ascending auditory pathway.

  13. Immunocytochemical profiles of inferior colliculus neurons in the rat and their changes with aging

    PubMed Central

    Ouda, Ladislav; Syka, Josef

    2012-01-01

    The inferior colliculus (IC) plays a strategic role in the central auditory system in relaying and processing acoustical information, and therefore its age-related changes may significantly influence the quality of the auditory function. A very complex processing of acoustical stimuli occurs in the IC, as supported also by the fact that the rat IC contains more neurons than all other subcortical auditory structures combined. GABAergic neurons, which predominantly co-express parvalbumin (PV), are present in the central nucleus of the IC in large numbers and to a lesser extent in the dorsal and external/lateral cortices of the IC. On the other hand, calbindin (CB) and calretinin (CR) are prevalent in the dorsal and external cortices of the IC, with only a few positive neurons in the central nucleus. The relationship between CB and CR expression in the IC and any neurotransmitter system has not yet been well established, but the distribution and morphology of the immunoreactive neurons suggest that they are at least partially non-GABAergic cells. The expression of glutamate decarboxylase (GAD) (a key enzyme for GABA synthesis) and calcium binding proteins (CBPs) in the IC of rats undergoes pronounced changes with aging that involve mostly a decline in protein expression and a decline in the number of immunoreactive neurons. Similar age-related changes in GAD, CB, and CR expression are present in the IC of two rat strains with differently preserved inner ear function up to late senescence (Long-Evans and Fischer 344), which suggests that these changes do not depend exclusively on peripheral deafferentation but are, at least partially, of central origin. These changes may be associated with the age-related deterioration in the processing of the temporal parameters of acoustical stimuli, which is not correlated with hearing threshold shifts, and therefore may contribute to central presbycusis. PMID:23049499

  14. Intralaminar stimulation of the inferior colliculus facilitates frequency-specific activation in the auditory cortex

    NASA Astrophysics Data System (ADS)

    Allitt, B. J.; Benjaminsen, C.; Morgan, S. J.; Paolini, A. G.

    2013-08-01

    Objective. Auditory midbrain implants (AMI) provide inadequate frequency discrimination for open set speech perception. AMIs that can take advantage of the tonotopic laminar of the midbrain may be able to better deliver frequency specific perception and lead to enhanced performance. Stimulation strategies that best elicit frequency specific activity need to be identified. This research examined the characteristic frequency (CF) relationship between regions of the auditory cortex (AC), in response to stimulated regions of the inferior colliculus (IC), comparing monopolar, and intralaminar bipolar electrical stimulation. Approach. Electrical stimulation using multi-channel micro-electrode arrays in the IC was used to elicit AC responses in anaesthetized male hooded Wistar rats. The rate of activity in AC regions with CFs within 3 kHz (CF-aligned) and unaligned CFs was used to assess the frequency specificity of responses. Main results. Both monopolar and bipolar IC stimulation led to CF-aligned neural activity in the AC. Altering the distance between the stimulation and reference electrodes in the IC led to changes in both threshold and dynamic range, with bipolar stimulation with 400 µm spacing evoking the lowest AC threshold and widest dynamic range. At saturation, bipolar stimulation elicited a significantly higher mean spike count in the AC at CF-aligned areas than at CF-unaligned areas when electrode spacing was 400 µm or less. Bipolar stimulation using electrode spacing of 400 µm or less also elicited a higher rate of elicited activity in the AC in both CF-aligned and CF-unaligned regions than monopolar stimulation. When electrodes were spaced 600 µm apart no benefit over monopolar stimulation was observed. Furthermore, monopolar stimulation of the external cortex of the IC resulted in more localized frequency responses than bipolar stimulation when stimulation and reference sites were 200 µm apart. Significance. These findings have implications for the

  15. Modulation of audiogenic seizures by histamine and adenosine receptors in the inferior colliculus.

    PubMed

    Feng, H J; Faingold, C L

    2000-05-01

    Susceptibility to behaviorally similar audiogenic seizures (AGS) occurs genetically and is inducible during ethanol withdrawal (ETX). Comparisons between AGS mechanisms of genetically epilepsy-prone rats (GEPR-9s) and ethanol-withdrawn rats (ETX-Rs) are yielding information about general pathophysiological mechanisms of epileptogenesis. The inferior colliculus (IC) is the AGS initiation site. Excitatory amino acid (EAA) abnormalities in the IC are implicated in AGS, and histamine and adenosine receptor activation each reduce EAA release and inhibit several seizure types. Previous studies indicate that focal infusion of an adenosine receptor agonist into the IC blocked AGS in GEPR-9s, but the effects of adenosine receptor activation in the IC on AGS in ETX-Rs are unknown. The effects of histamine receptor activation on either form of AGS are also unexamined. The present study evaluated effects of histamine or a nonselective adenosine A(1) agonist, 2-chloroadenosine, on AGS by focal microinjection into the IC. Ethanol dependence and AGS susceptibility were induced in normal rats by intragastric ethanol. Histamine (40 or 60 nmol/side) significantly reduced AGS in GEPR-9s, but histamine in doses up to 120 nmol/side did not affect AGS in ETX-Rs. 2-Chloroadenosine (5 or 10 nmol/side) did not affect AGS in ETX-Rs, despite the effectiveness of lower doses of this agent in GEPR-9s reported previously. Thus, histamine and adenosine receptors in the IC modulate AGS of GEPR-9s, but do not modulate ETX-induced AGS. The reasons for this difference may involve the chronicity of AGS susceptibility in GEPR-9s, which may lead to more extensive neuromodulation as compensatory mechanisms to limit the seizures compared to the acute AGS of ETX-Rs.

  16. Effect of current focusing on the sensitivity of inferior colliculus neurons to amplitude-modulated stimulation.

    PubMed

    George, Shefin S; Shivdasani, Mohit N; Fallon, James B

    2016-09-01

    In multichannel cochlear implants (CIs), current is delivered to specific electrodes along the cochlea in the form of amplitude-modulated pulse trains, to convey temporal and spectral cues. Our previous studies have shown that focused multipolar (FMP) and tripolar (TP) stimulation produce more restricted neural activation and reduced channel interactions in the inferior colliculus (IC) compared with traditional monopolar (MP) stimulation, suggesting that focusing of stimulation could produce better transmission of spectral information. The present study explored the capability of IC neurons to detect modulated CI stimulation with FMP and TP stimulation compared with MP stimulation. The study examined multiunit responses of IC neurons in acutely deafened guinea pigs by systematically varying the stimulation configuration, modulation depth, and stimulation level. Stimuli were sinusoidal amplitude-modulated pulse trains (carrier rate of 120 pulses/s). Modulation sensitivity was quantified by measuring modulation detection thresholds (MDTs), defined as the lowest modulation depth required to differentiate the response of a modulated stimulus from an unmodulated one. Whereas MP stimulation showed significantly lower MDTs than FMP and TP stimulation (P values <0.05) at stimulation ≤2 dB above threshold, all stimulation configurations were found to have similar modulation sensitivities at 4 dB above threshold. There was no difference found in modulation sensitivity between FMP and TP stimulation. The present study demonstrates that current focusing techniques such as FMP and TP can adequately convey amplitude modulation and are comparable to MP stimulation, especially at higher stimulation levels, although there may be some trade-off between spectral and temporal fidelity with current focusing stimulation.

  17. Mechanisms of spectral and temporal integration in the mustached bat inferior colliculus

    PubMed Central

    Wenstrup, Jeffrey James; Nataraj, Kiran; Sanchez, Jason Tait

    2012-01-01

    This review describes mechanisms and circuitry underlying combination-sensitive response properties in the auditory brainstem and midbrain. Combination-sensitive neurons, performing a type of auditory spectro-temporal integration, respond to specific, properly timed combinations of spectral elements in vocal signals and other acoustic stimuli. While these neurons are known to occur in the auditory forebrain of many vertebrate species, the work described here establishes their origin in the auditory brainstem and midbrain. Focusing on the mustached bat, we review several major findings: (1) Combination-sensitive responses involve facilitatory interactions, inhibitory interactions, or both when activated by distinct spectral elements in complex sounds. (2) Combination-sensitive responses are created in distinct stages: inhibition arises mainly in lateral lemniscal nuclei of the auditory brainstem, while facilitation arises in the inferior colliculus (IC) of the midbrain. (3) Spectral integration underlying combination-sensitive responses requires a low-frequency input tuned well below a neuron's characteristic frequency (ChF). Low-ChF neurons in the auditory brainstem project to high-ChF regions in brainstem or IC to create combination sensitivity. (4) At their sites of origin, both facilitatory and inhibitory combination-sensitive interactions depend on glycinergic inputs and are eliminated by glycine receptor blockade. Surprisingly, facilitatory interactions in IC depend almost exclusively on glycinergic inputs and are largely independent of glutamatergic and GABAergic inputs. (5) The medial nucleus of the trapezoid body (MNTB), the lateral lemniscal nuclei, and the IC play critical roles in creating combination-sensitive responses. We propose that these mechanisms, based on work in the mustached bat, apply to a broad range of mammals and other vertebrates that depend on temporally sensitive integration of information across the audible spectrum. PMID:23109917

  18. Natural Vocalizations in the Mammalian Inferior Colliculus are Broadly Encoded by a Small Number of Independent Multi-Units

    PubMed Central

    Lyzwa, Dominika; Herrmann, J. Michael; Wörgötter, Florentin

    2016-01-01

    How complex natural sounds are represented by the main converging center of the auditory midbrain, the central inferior colliculus, is an open question. We applied neural discrimination to determine the variation of detailed encoding of individual vocalizations across the best frequency gradient of the central inferior colliculus. The analysis was based on collective responses from several neurons. These multi-unit spike trains were recorded from guinea pigs exposed to a spectrotemporally rich set of eleven species-specific vocalizations. Spike trains of disparate units from the same recording were combined in order to investigate whether groups of multi-unit clusters represent the whole set of vocalizations more reliably than only one unit, and whether temporal response correlations between them facilitate an unambiguous neural representation of the vocalizations. We found a spatial distribution of the capability to accurately encode groups of vocalizations across the best frequency gradient. Different vocalizations are optimally discriminated at different locations of the best frequency gradient. Furthermore, groups of a few multi-unit clusters yield improved discrimination over only one multi-unit cluster between all tested vocalizations. However, temporal response correlations between units do not yield better discrimination. Our study is based on a large set of units of simultaneously recorded responses from several guinea pigs and electrode insertion positions. Our findings suggest a broadly distributed code for behaviorally relevant vocalizations in the mammalian inferior colliculus. Responses from a few non-interacting units are sufficient to faithfully represent the whole set of studied vocalizations with diverse spectrotemporal properties. PMID:26869890

  19. Extracellular Molecular Markers and Soma Size of Inhibitory Neurons: Evidence for Four Subtypes of GABAergic Cells in the Inferior Colliculus

    PubMed Central

    Beebe, Nichole L.; Young, Jesse W.; Mellott, Jeffrey G.

    2016-01-01

    Inhibition plays an important role in shaping responses to stimuli throughout the CNS, including in the inferior colliculus (IC), a major hub in both ascending and descending auditory pathways. Subdividing GABAergic cells has furthered the understanding of inhibition in many brain areas, most notably in the cerebral cortex. Here, we seek the same understanding of subcortical inhibitory cell types by combining staining for two types of extracellular markers—perineuronal nets (PNs) and perisomatic rings of terminals expressing vesicular glutamate transporter 2 (VGLUT2) —to subdivide IC GABAergic cells in adult guinea pigs. We found four distinct groups of GABAergic cells in the IC: (1) those with both a PN and a VGLUT2 ring; (2) those with only a PN; (3) those with only a VGLUT2 ring; and (4) those with neither marker. In addition, these four GABAergic subtypes differ in their soma size and distribution among IC subdivisions. Functionally, the presence or absence of VGLUT2 rings indicates differences in inputs, whereas the presence or absence of PNs indicates different potential for plasticity and temporal processing. We conclude that these markers distinguish four GABAergic subtypes that almost certainly serve different roles in the processing of auditory stimuli within the IC. SIGNIFICANCE STATEMENT GABAergic inhibition plays a critical role throughout the brain. Identification of subclasses of GABAergic cells (up to 15 in the cerebral cortex) has furthered the understanding of GABAergic roles in circuit modulation. Inhibition is also prominent in the inferior colliculus, a subcortical hub in auditory pathways. Here, we use two extracellular markers to identify four distinct groups of GABAergic cells. Perineuronal nets and perisomatic rings of glutamatergic boutons are present in many subcortical areas and often are associated with inhibitory cells, but they have rarely been used to identify inhibitory subtypes. Our results further the understanding of

  20. Natural Vocalizations in the Mammalian Inferior Colliculus are Broadly Encoded by a Small Number of Independent Multi-Units.

    PubMed

    Lyzwa, Dominika; Herrmann, J Michael; Wörgötter, Florentin

    2015-01-01

    How complex natural sounds are represented by the main converging center of the auditory midbrain, the central inferior colliculus, is an open question. We applied neural discrimination to determine the variation of detailed encoding of individual vocalizations across the best frequency gradient of the central inferior colliculus. The analysis was based on collective responses from several neurons. These multi-unit spike trains were recorded from guinea pigs exposed to a spectrotemporally rich set of eleven species-specific vocalizations. Spike trains of disparate units from the same recording were combined in order to investigate whether groups of multi-unit clusters represent the whole set of vocalizations more reliably than only one unit, and whether temporal response correlations between them facilitate an unambiguous neural representation of the vocalizations. We found a spatial distribution of the capability to accurately encode groups of vocalizations across the best frequency gradient. Different vocalizations are optimally discriminated at different locations of the best frequency gradient. Furthermore, groups of a few multi-unit clusters yield improved discrimination over only one multi-unit cluster between all tested vocalizations. However, temporal response correlations between units do not yield better discrimination. Our study is based on a large set of units of simultaneously recorded responses from several guinea pigs and electrode insertion positions. Our findings suggest a broadly distributed code for behaviorally relevant vocalizations in the mammalian inferior colliculus. Responses from a few non-interacting units are sufficient to faithfully represent the whole set of studied vocalizations with diverse spectrotemporal properties. PMID:26869890

  1. Comparison of Gain-Like Properties of Eye Position Signals in Inferior Colliculus Versus Auditory Cortex of Primates

    PubMed Central

    Maier, Joost X.; Groh, Jennifer M.

    2010-01-01

    We evaluated to what extent the influence of eye position in the auditory pathway of primates can be described as a gain field. We compared single unit activity in the inferior colliculus (IC), core auditory cortex (A1) and the caudomedial belt (CM) region of auditory cortex (AC) in primates, and found stronger evidence for gain field-like interactions in the IC than in AC. In the IC, eye position signals showed both multiplicative and additive interactions with auditory responses, whereas in AC the effects were not as well predicted by a gain field model. PMID:20838470

  2. Response selectivity for multiple dimensions of frequency sweeps in the pallid bat inferior colliculus.

    PubMed

    Fuzessery, Z M

    1994-09-01

    1. While hunting, the pallid bat uses passive sound localization at low frequencies to find terrestrial prey, and echolocation for general orientation. It must therefore process two different types of acoustic input at the same time. The pallid bat's echolocation pulse is a downward frequency-modulated (FM) sweep from 60 to 30 kHz. This study examined the response selectivity of single neurons in the pallid bat's central nucleus of the inferior colliculus (ICC) for FM sweeps, comparing the response properties of the high-frequency population, tuned to the biosonar pulse, with the low-frequency population, tuned below the pulse. The working hypothesis was that the high-frequency population would exhibit a response selectivity for downward FM sweeps that was not present in the low-frequency population. 2. Neurons were tested for their selectivity for FM sweep direction, duration, frequency range and bandwidth, and rate of frequency change. The extent to which they responded exclusively to tones, noise, and FM sweeps was also examined. Significant differences in the response properties of neurons in the two populations were found. In the low-frequency population, all neurons responded to tones, but only 50% responded to FM sweeps. Only 23% were selective for sweep direction. In the high-frequency population, all neurons responded to FM sweeps, but 31% did not respond to tones. Over one-half of this population was selective for sweep direction, and of those that were selective, all preferred the downward sweep direction of the biosonar pulse. A large percentage (31%) responded exclusively to downward sweeps, and not to tones or upward sweeps. None of the cells in either population responded to noise, or did so only at very high relative thresholds. 3. Both populations contained neurons that were selective for short stimulus durations that approximated the duration of the biosonar pulse, although the percentage was greater in the high-frequency population (58% vs. 20

  3. Inferior colliculus contributions to phase encoding of stop consonants in an animal model.

    PubMed

    Warrier, Catherine M; Abrams, Daniel A; Nicol, Trent G; Kraus, Nina

    2011-12-01

    The human auditory brainstem is known to be exquisitely sensitive to fine-grained spectro-temporal differences between speech sound contrasts, and the ability of the brainstem to discriminate between these contrasts is important for speech perception. Recent work has described a novel method for translating brainstem timing differences in response to speech contrasts into frequency-specific phase differentials. Results from this method have shown that the human brainstem response is surprisingly sensitive to phase differences inherent to the stimuli across a wide extent of the spectrum. Here we use an animal model of the auditory brainstem to examine whether the stimulus-specific phase signatures measured in human brainstem responses represent an epiphenomenon associated with far-field (i.e., scalp-recorded) measurement of neural activity, or alternatively whether these specific activity patterns are also evident in auditory nuclei that contribute to the scalp-recorded response, thereby representing a more fundamental temporal processing phenomenon. Responses in anaesthetized guinea pigs to three minimally-contrasting consonant-vowel stimuli were collected simultaneously from the cortical surface vertex and directly from central nucleus of the inferior colliculus (ICc), measuring volume conducted neural activity and multiunit, near-field activity, respectively. Guinea pig surface responses were similar to human scalp-recorded responses to identical stimuli in gross morphology as well as phase characteristics. Moreover, surface-recorded potentials shared many phase characteristics with near-field ICc activity. Response phase differences were prominent during formant transition periods, reflecting spectro-temporal differences between syllables, and showed more subtle differences during the identical steady state periods. ICc encoded stimulus distinctions over a broader frequency range, with differences apparent in the highest frequency ranges analyzed, up to 3000

  4. BOLD fMRI study of ultrahigh frequency encoding in the inferior colliculus.

    PubMed

    Gao, Patrick P; Zhang, Jevin W; Chan, Russell W; Leong, Alex T L; Wu, Ed X

    2015-07-01

    Many vertebrates communicate with ultrahigh frequency (UHF) vocalizations to limit auditory detection by predators. The mechanisms underlying the neural encoding of such UHF sounds may provide important insights for understanding neural processing of other complex sounds (e.g. human speeches). In the auditory system, sound frequency is normally encoded topographically as tonotopy, which, however, contains very limited representation of UHFs in many species. Instead, electrophysiological studies suggested that two neural mechanisms, both exploiting the interactions between frequencies, may contribute to UHF processing. Neurons can exhibit excitatory or inhibitory responses to a tone when another UHF tone is presented simultaneously (combination sensitivity). They can also respond to such stimulation if they are tuned to the frequency of the cochlear-generated distortion products of the two tones, e.g. their difference frequency (cochlear distortion). Both mechanisms are present in an early station of the auditory pathway, the midbrain inferior colliculus (IC). Currently, it is unclear how prevalent the two mechanisms are and how they are functionally integrated in encoding UHFs. This study investigated these issues with large-view BOLD fMRI in rat auditory system, particularly the IC. UHF vocalizations (above 40kHz), but not pure tones at similar frequencies (45, 55, 65, 75kHz), evoked robust BOLD responses in multiple auditory nuclei, including the IC, reinforcing the sensitivity of the auditory system to UHFs despite limited representation in tonotopy. Furthermore, BOLD responses were detected in the IC when a pair of UHF pure tones was presented simultaneously (45 & 55kHz, 55 & 65kHz, 45 & 65kHz, 45 & 75kHz). For all four pairs, a cluster of voxels in the ventromedial side always showed the strongest responses, displaying combination sensitivity. Meanwhile, voxels in the dorsolateral side that showed strongest secondary responses to each pair of UHF pure tones

  5. NMDA and non-NMDA glutamate receptors in auditory transmission in the barn owl inferior colliculus.

    PubMed

    Feldman, D E; Knudsen, E I

    1994-10-01

    The pharmacology of auditory responses in the inferior colliculus (IC) of the barn owl was investigated by iontophoresis of excitatory amino acid receptor antagonists into two different functional subdivisions of the IC, the external nucleus (ICx) and the lateral shell of the central nucleus (lateral shell), both of which carry out important computations in the processing of auditory spatial information. Combined application of the NMDA receptor antagonist 2-amino-5-phosphonovaleric acid (AP5) and the non-NMDA receptor antagonist 6-cyano-5-nitroquinoxaline-2,3-dione (CNQX) significantly reduced auditory-evoked spikes at all sites in these two subdivisions, and completely eliminated responses at many locations. This suggests that excitatory amino acid receptors mediate the bulk, if not all, of auditory responses in the ICx and lateral shell. NMDA and non-NMDA receptors contributed differently to auditory responses in the two subdivisions. In the ICx, AP5 significantly reduced the number of auditory-evoked spikes at every site tested. On average, AP5 eliminated 55% of auditory-evoked spikes at multiunit sites and 64% at single-unit sites in this structure. In contrast, in the lateral shell, AP5 significantly reduced responses at less than half the sites tested, and, on average, AP5 eliminated only 19% of spikes at multiunit sites and 25% at single-unit sites. When the magnitude of response blockade produced by AP5 at individual multiunit sites was normalized to adjust for site-to-site differences in the efficacy of iontophoresed AP5 and CNQX, AP5 blockade was still significantly greater in the ICx than the lateral shell. CNQX application strongly reduced responses in both subdivisions. These data suggest that NMDA receptor currents make a major contribution to auditory responses in the ICx, while they make only a small contribution to auditory responses in the lateral shell. Non-NMDA receptor currents, on the other hand, contribute to auditory responses in both

  6. Spatial selectivity and binaural responses in the inferior colliculus of the great horned owl.

    PubMed

    Volman, S F; Konishi, M

    1989-09-01

    In this study we have investigated the processing of auditory cues for sound localization in the great horned owl (Bubo virginianus). Previous studies have shown that the barn owl, whose ears are asymmetrically oriented in the vertical plane, has a 2-dimensional, topographic representation of auditory space in the external division of the inferior colliculus (ICx). As in the barn owl, the great horned owl's ICx is anatomically distinct and projects to the optic tectum. Neurons in ICx respond over only a small range of azimuths (mean = 32 degrees), and azimuth is topographically mapped. In contrast to the barn owl, the great horned owl has bilaterally symmetrical ears and its receptive fields are not restricted in elevation. The binaural cues available for sound localization were measured both with cochlear microphonic recordings and with a microphone attached to a probe tube in the auditory canal. Interaural time disparity (ITD) varied monotonically with azimuth. Interaural intensity differences (IID) also changed with azimuth, but the largest IIDs were less than 15 dB, and the variation was not monotonic. Neither ITD nor IID varied systematically with changes in the vertical position of a sound source. We used dichotic stimulation to determine the sensitivity of ICx neurons to these binaural cues. Best ITD of ICx units was topographically mapped and strongly correlated with receptive-field azimuth. The width of ITD tuning curves, measured at 50% of the maximum response, averaged 72 microseconds. All ICx neurons responded only to binaural stimulation and had nonmonotonic IID tuning curves. Best IID was weakly, but significantly, correlated with best ITD (r = 0.39, p less than 0.05). The IID tuning curves, however, were broad (mean 50% width = 24 dB), and 67% of the units had best IIDs within 5 dB of 0 dB IID. ITD tuning was sensitive to variations in IID in the direction opposite to that expected for time-intensity trading, but the magnitude of this effect was only

  7. Anatomical differences in the human inferior colliculus relate to the perceived valence of musical consonance and dissonance.

    PubMed

    Fritz, Thomas Hans; Renders, Wiske; Müller, Karsten; Schmude, Paul; Leman, Marc; Turner, Robert; Villringer, Arno

    2013-10-01

    Helmholtz himself speculated about a role of the cochlea in the perception of musical dissonance. Here we indirectly investigated this issue, assessing the valence judgment of musical stimuli with variable consonance/dissonance and presented diotically (exactly the same dissonant signal was presented to both ears) or dichotically (a consonant signal was presented to each ear--both consonant signals were rhythmically identical but differed by a semitone in pitch). Differences in brain organisation underlying inter-subject differences in the percept of dichotically presented dissonance were determined with voxel-based morphometry. Behavioral results showed that diotic dissonant stimuli were perceived as more unpleasant than dichotically presented dissonance, indicating that interactions within the cochlea modulated the valence percept during dissonance. However, the behavioral data also suggested that the dissonance percept did not depend crucially on the cochlea, but also occurred as a result of binaural integration when listening to dichotic dissonance. These results also showed substantial between-participant variations in the valence response to dichotic dissonance. These differences were in a voxel-based morphometry analysis related to differences in gray matter density in the inferior colliculus, which strongly substantiated a key role of the inferior colliculus in consonance/dissonance representation in humans.

  8. Functional magnetic resonance imaging confirms forward suppression for rapidly alternating sounds in human auditory cortex but not in the inferior colliculus.

    PubMed

    Uhlig, Christian Harm; Dykstra, Andrew R; Gutschalk, Alexander

    2016-05-01

    Forward suppression at the level of the auditory cortex has been suggested to subserve auditory stream segregation. Recent results in non-streaming stimulation contexts have indicated that forward suppression can also be observed in the inferior colliculus; whether this holds for streaming-related contexts remains unclear. Here, we used cardiac-gated fMRI to examine forward suppression in the inferior colliculus (and the rest of the human auditory pathway) in response to canonical streaming stimuli (rapid tone sequences comprised of either one repetitive tone or two alternating tones). The first stimulus is typically perceived as a single stream, the second as two interleaved streams. In different experiments using either pure tones differing in frequency or bandpass-filtered noise differing in inter-aural time differences, we observed stronger auditory cortex activation in response to alternating vs. repetitive stimulation, consistent with the presence of forward suppression. In contrast, activity in the inferior colliculus and other subcortical nuclei did not significantly differ between alternating and monotonic stimuli. This finding could be explained by active amplification of forward suppression in auditory cortex, by a low rate (or absence) of cells showing forward suppression in inferior colliculus, or both.

  9. Topographic projection from the optic tectum to the auditory space map in the inferior colliculus of the barn owl.

    PubMed

    Hyde, P S; Knudsen, E I

    2000-05-29

    In the barn owl (Tyto alba), the external nucleus of the inferior colliculus (ICX) contains a map of auditory space that is calibrated by visual experience. The source of the visually based instructive signal to the ICX is unknown. Injections of biotinylated dextran amine and Fluoro-Gold in the ICX retrogradely labelled neurons in layers 8-15 of the ipsilateral optic tectum (OT) that could carry this instructive signal. This projection was point-to-point and in register with the feed-forward, auditory projection from the ICX to the OT. Most labelled neurons were in layers 10-11, and most were bipolar. Tripolar, multipolar, and unipolar neurons were also observed. Multipolar neurons had dendrites that were oriented parallel to the tectal laminae. In contrast, most labelled bipolar and tripolar neurons had dendrites oriented perpendicular to the tectal laminae, extending superficially into the retino-recipient laminae and deep into the auditory recipient laminae. Therefore, these neurons were positioned to receive both visual and auditory information from particular locations in space. Biocytin injected into the superficial layers of the OT labelled bouton-laden axons in the ICX. These axons were generally finer than, but had similar bouton densities as, feed-forward auditory fibers in the ICX, labelled by injections of biocytin into the central nucleus of the inferior colliculus (ICC). These data demonstrate a point-to-point projection from the OT to the ICX that could provide a spatial template for calibrating the auditory space map in the ICX. PMID:10813778

  10. Projections of physiologically defined subdivisions of the inferior colliculus in the mustached bat: targets in the medial geniculate body and extrathalamic nuclei.

    PubMed

    Wenstrup, J J; Larue, D T; Winer, J A

    1994-08-01

    This study examined the output of the central nucleus of the inferior colliculus to the medial geniculate body and other parts of the nervous system in the mustached bat (Pteronotus parnellii). Small deposits of anterograde tracers (horseradish peroxidase, [3H]leucine, Phaseolus vulgaris leucoagglutinin, wheat germ agglutinin conjugated to horseradish peroxidase, or biocytin) were made at physiologically defined sites in the central nucleus representing major components of the bat's echolocation signal. The topography, frequency specificity, and axonal morphology of these outputs were studied. The medial geniculate body was a major target of inferior collicular neurons, with three distinct input patterns. The projection to the ventral division was tonotopically organized, but had a relatively sparse contribution from neurons representing frequency modulated components of the biosonar pulse. The second input was to the rostral medial geniculate body, in which projections from inferior collicular neurons representing constant frequency sonar components were separated from those representing frequency modulated components. A third input was to the suprageniculate nucleus, which received strong, topographically arranged projections. Inputs to the dorsal nucleus and medial division were also observed. Extrathalamic regions receiving input included the pontine gray, external nucleus of the inferior colliculus, pericollicular tegmentum, nucleus of the brachium of the inferior colliculus, and pretectum. These central nucleus projections differed in organization and the structure of axon terminals, suggesting different physiological influences on their target nuclei. These results demonstrate that the central nucleus has divergent projections to various sensory and premotor nuclei, besides its well-established projection to the medial geniculate body.

  11. Activation of the serotonin 1A receptor alters the temporal characteristics of auditory responses in the inferior colliculus.

    PubMed

    Hurley, Laura M

    2007-11-21

    Serotonin, like other neuromodulators, acts on a range of receptor types, but its effects also depend on the functional characteristics of the neurons responding to receptor activation. In the inferior colliculus (IC), an auditory midbrain nucleus, activation of a common serotonin (5-HT) receptor type, the 5-HT 1A receptor, depresses auditory-evoked responses in many neurons. Whether these effects occur differentially in different types of neurons is unknown. In the current study, the effects of iontophoretic application of the 5-HT 1A agonist 8-OH-DPAT on auditory responses were compared with the characteristic frequencies (CFs), recording depths, and control first-spike latencies of the same group of IC neurons. The 8-OH-DPAT-evoked change in response significantly correlated with first-spike latency across the population, so that response depressions were more prevalent in longer-latency neurons. The 8-OH-DPAT-evoked change in response did not correlate with CF or with recording depth. 8-OH-DPAT also altered the temporal characteristics of spike trains in a subset of neurons that fired multiple spikes in response to brief stimuli. For these neurons, activation of the 5-HT 1A receptor suppressed lagging spikes proportionally more than initial spikes. These results suggest that the 5-HT 1A receptor, by affecting the timing of the responses of both individual neurons and the neuron population, shifts the temporal profile of evoked activity within the IC. PMID:17916336

  12. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity.

    PubMed

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S

    2016-04-12

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or "deviance" detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons' overall tuning widths.

  13. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity

    PubMed Central

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S.

    2016-01-01

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or “deviance” detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons’ overall tuning widths. PMID:27066835

  14. Wisteria Floribunda Agglutinin-Labeled Perineuronal Nets in the Mouse Inferior Colliculus, Thalamic Reticular Nucleus and Auditory Cortex

    PubMed Central

    Fader, Sarah M.; Imaizumi, Kazuo; Yanagawa, Yuchio; Lee, Charles C.

    2016-01-01

    Perineuronal nets (PNNs) are specialized extracellular matrix molecules that are associated with the closing of the critical period, among other functions. In the adult brain, PNNs surround specific types of neurons, however the expression of PNNs in the auditory system of the mouse, particularly at the level of the midbrain and forebrain, has not been fully described. In addition, the association of PNNs with excitatory and inhibitory cell types in these structures remains unknown. Therefore, we sought to investigate the expression of PNNs in the inferior colliculus (IC), thalamic reticular nucleus (TRN) and primary auditory cortex (A1) of the mouse brain by labeling with wisteria floribunda agglutinin (WFA). To aid in the identification of inhibitory neurons in these structures, we employed the vesicular GABA transporter (VGAT)-Venus transgenic mouse strain, which robustly expresses an enhanced yellow-fluorescent protein (Venus) natively in nearly all gamma-amino butyric acid (GABA)-ergic inhibitory neurons, thus enabling a rapid and unambiguous assessment of inhibitory neurons throughout the nervous system. Our results demonstrate that PNNs are expressed throughout the auditory midbrain and forebrain, but vary in their local distribution. PNNs are most dense in the TRN and least dense in A1. Furthermore, PNNs are preferentially associated with inhibitory neurons in A1 and the TRN, but not in the IC of the mouse. These data suggest regionally specific roles for PNNs in auditory information processing. PMID:27089371

  15. Target representation of naturalistic echolocation sequences in single unit responses from the inferior colliculus of big brown bats

    NASA Astrophysics Data System (ADS)

    Sanderson, Mark I.; Simmons, James A.

    2005-11-01

    Echolocating big brown bats (Eptesicus fuscus) emit trains of frequency-modulated (FM) biosonar signals whose duration, repetition rate, and sweep structure change systematically during interception of prey. When stimulated with a 2.5-s sequence of 54 FM pulse-echo pairs that mimic sounds received during search, approach, and terminal stages of pursuit, single neurons (N=116) in the bat's inferior colliculus (IC) register the occurrence of a pulse or echo with an average of <1 spike/sound. Individual IC neurons typically respond to only a segment of the search or approach stage of pursuit, with fewer neurons persisting to respond in the terminal stage. Composite peristimulus-time-histogram plots of responses assembled across the whole recorded population of IC neurons depict the delay of echoes and, hence, the existence and distance of the simulated biosonar target, entirely as on-response latencies distributed across time. Correlated changes in pulse duration, repetition rate, and pulse or echo amplitude do modulate the strength of responses (probability of the single spike actually occurring for each sound), but registration of the target itself remains confined exclusively to the latencies of single spikes across cells. Modeling of echo processing in FM biosonar should emphasize spike-time algorithms to explain the content of biosonar images.

  16. Wisteria Floribunda Agglutinin-Labeled Perineuronal Nets in the Mouse Inferior Colliculus, Thalamic Reticular Nucleus and Auditory Cortex.

    PubMed

    Fader, Sarah M; Imaizumi, Kazuo; Yanagawa, Yuchio; Lee, Charles C

    2016-01-01

    Perineuronal nets (PNNs) are specialized extracellular matrix molecules that are associated with the closing of the critical period, among other functions. In the adult brain, PNNs surround specific types of neurons, however the expression of PNNs in the auditory system of the mouse, particularly at the level of the midbrain and forebrain, has not been fully described. In addition, the association of PNNs with excitatory and inhibitory cell types in these structures remains unknown. Therefore, we sought to investigate the expression of PNNs in the inferior colliculus (IC), thalamic reticular nucleus (TRN) and primary auditory cortex (A1) of the mouse brain by labeling with wisteria floribunda agglutinin (WFA). To aid in the identification of inhibitory neurons in these structures, we employed the vesicular GABA transporter (VGAT)-Venus transgenic mouse strain, which robustly expresses an enhanced yellow-fluorescent protein (Venus) natively in nearly all gamma-amino butyric acid (GABA)-ergic inhibitory neurons, thus enabling a rapid and unambiguous assessment of inhibitory neurons throughout the nervous system. Our results demonstrate that PNNs are expressed throughout the auditory midbrain and forebrain, but vary in their local distribution. PNNs are most dense in the TRN and least dense in A1. Furthermore, PNNs are preferentially associated with inhibitory neurons in A1 and the TRN, but not in the IC of the mouse. These data suggest regionally specific roles for PNNs in auditory information processing. PMID:27089371

  17. Activation of the serotonin 1A receptor alters the temporal characteristics of auditory responses in the inferior colliculus

    PubMed Central

    Hurley, Laura M.

    2008-01-01

    Serotonin, like other neuromodulators, acts on a range of receptor types, but its effects also depend on the functional characteristics of the neurons responding to receptor activation. In the inferior colliculus (IC), an auditory midbrain nucleus, activation of a common serotonin (5-HT) receptor type, the 5-HT1A receptor, depresses auditory-evoked responses in many neurons. Whether these effects occur differentially in different types of neurons is unknown. In the current study, the effects of iontophoretic application of the 5-HT1A agonist 8-OH-DPAT on auditory responses were compared with the characteristic frequencies (CFs), recording depths, and control first-spike latencies of the same group of IC neurons. The 8-OH-DPAT-evoked change in response significantly correlated with first-spike latency across the population, so that response depressions were more prevalent in longer-latency neurons. The 8-OH-DPAT-evoked change in response did not correlate with CF or with recording depth. 8-OH-DPAT also altered the temporal characteristics of spike trains in a subset of neurons that fired multiple spikes in response to brief stimuli. For these neurons, activation of the 5-HT1A receptor suppressed lagging spikes proportionally more than initial spikes. These results suggest that the 5-HT1A receptor, by affecting the timing of the responses of both individual neurons and the neuron population, shifts the temporal profile of evoked activity within the IC. PMID:17916336

  18. Response properties and location of neurons selective for sinusoidal frequency modulations in the inferior colliculus of the big brown bat.

    PubMed

    Yue, Qi; Casseday, John H; Covey, Ellen

    2007-09-01

    Most animal vocalizations, including echolocation signals used by bats, contain frequency-modulated (FM) components. Previous studies have described a class of neurons in the inferior colliculus (IC) of the big brown bat that respond exclusively to sinusoidally frequency modulated (SFM) signals and fail to respond to pure tones, noise, amplitude-modulated tones, or single FM sweeps. The aims of this study were to further characterize these neurons' response properties and to determine whether they are localized within a specific area of the IC. We recorded extracellularly from 214 neurons throughout the IC. Of these, 47 (22%) responded exclusively to SFM. SFM-selective cells were tuned to relatively low carrier frequencies (9-50 kHz), low modulation rates (20-210 Hz), and shallow modulation depths (3-10 kHz). Most had extremely low thresholds, with an average of 16.5 +/- 7.6 dB SPL, and 89% had upper thresholds and closed response areas. For SFM-selective cells with spontaneous activity, the spontaneous activity was eliminated when sound amplitude exceeded their upper threshold and resumed after the stimulus was over. These findings suggest that SFM-selective cells receive low-threshold excitatory inputs and high-threshold inhibitory inputs. SFM-selective cells were clustered in the rostrodorsal part of the IC. Within this area, best modulation rate appeared to be correlated with best carrier frequency and depth within the IC.

  19. Ontogenesis of auditory fovea representation in the inferior colliculus of the Sri Lankan rufous horseshoe bat, Rhinolophus rouxi.

    PubMed

    Rübsamen, R; Schäfer, M

    1990-12-01

    This report describes the ontogenesis of tonotopy in the inferior colliculus (IC) of the rufous horseshoe bat (Rhinolophus rouxi). Horseshoe bats are deaf at birth, but consistent tonotopy with a low-to-high frequency gradient from dorsolateral to ventromedial develops from the 2nd up to the 5th week. The representation of the auditory fovea is established in ventro-medio-caudal parts of the IC during the 3rd postnatal week (Fig. 3). Then, a narrow frequency band 5 kHz in width, comprising 16% of the bat's auditory range, captures 50-60 vol% of the IC (Fig. 3c). However, foveal tuning is 10-12 kHz (1/3 octave) lower than in adults; foveal tuning in females (65-68 kHz) is 2-3 kHz higher than in males (62-65 Khz). Thereafter, foveal tuning increases by 1-1.5 kHz per day up to the 5th postnatal week, when the adult hearing range is established (Figs. 4, 5). The increase of sensitivity and of tuning sharpness of single units also follows a low-to-high frequency gradient (Fig. 6). Throughout this development the foveal tuning matches the second harmonic of the echolocation pulses vocalised by these young bats. The results confirm the hypothesis of developmental shifts in the frequency-place code for the foveal high frequency representation in the IC.

  20. Effects of microinjections of apomorphine and haloperidol into the inferior colliculus on the latent inhibition of the conditioned emotional response.

    PubMed

    Melo, Liana L; Pereira, Ellen C H M; Pagini, Cássia H; Coimbra, Norberto C; Brandão, Marcus L; Ferrari, Elenice A M

    2009-03-01

    Electrical or chemical stimulation of the inferior colliculus (IC) induces fear-like behaviors. More recently, consistent evidence has shown that electrical stimulation of the central nucleus of the IC supports Pavlovian conditioning and latent inhibition (LI). LI is characterized by retardation in conditioning and also by an impaired ability to ignore irrelevant stimuli, after a non-reinforced pre-exposure to the conditioned stimulus. LI has been proposed as a behavioral model of cognitive abnormalities seen in schizophrenia. The aim of the present study was to determine whether dopaminergic mechanisms in the IC are involved in LI of the conditioned emotional response (CER). To induce LI, a group of rats was pre-exposed (PE) to six tones in two sessions, while rats that were not pre-exposed (NPE) had two sessions without tone presentations. The conditioning consisted of two tone presentations to the animal, followed immediately by a foot shock. PE and NPE rats received IC microinjections of physiological saline, the dopaminergic agonist apomorphine (9.0 microg/0.5 microL/side), or the dopaminergic antagonist haloperidol (0.5 microg/0.5 microL/side) before both pre-exposure and conditioning. During the test, the PE rats that received saline or haloperidol had a lower suppression of the licking response compared to NPE rats that received vehicle or haloperidol, indicating that latent inhibition was induced. There was no significant difference in the suppression ratio in rats that received apomorphine injections into the IC, indicating reduced latent inhibition. These results suggest that dopamine-mediated mechanisms of the IC are involved in the development of LI.

  1. The dissimilar time course of temporary threshold shifts and reduction of inhibition in the inferior colliculus following intense sound exposure.

    PubMed

    Heeringa, A N; van Dijk, P

    2014-06-01

    Excessive noise exposure is known to produce an auditory threshold shift, which can be permanent or transient in nature. Recent studies showed that noise-induced temporary threshold shifts are associated with loss of synaptic connections to the inner hair cells and with cochlear nerve degeneration, which is reflected in a decreased amplitude of wave I of the auditory brainstem response (ABR). This suggests that, despite normal auditory thresholds, central auditory processing may be abnormal. We recorded changes in central auditory processing following a sound-induced temporary threshold shift. Anesthetized guinea pigs were exposed for 1 h to a pure tone of 11 kHz (124 dB sound pressure level). Hearing thresholds, amplitudes of ABR waves I and IV, and spontaneous and tone-evoked firing rates in the inferior colliculus (IC) were assessed immediately, one week, two weeks, and four weeks post exposure. Hearing thresholds were elevated immediately following overexposure, but recovered within one week. The amplitude of the ABR wave I was decreased in all sound-exposed animals for all test periods. In contrast, the ABR wave IV amplitude was only decreased immediately after overexposure and recovered within a week. The proportion of IC units that show inhibitory responses to pure tones decreased substantially up to two weeks after overexposure, especially when stimulated with high frequencies. The proportion of excitatory responses to low frequencies was increased. Spontaneous activity was unaffected by the overexposure. Despite rapid normalization of auditory thresholds, our results suggest an increased central gain following sound exposure and an abnormal balance between excitatory and inhibitory responses in the midbrain up to two weeks after overexposure. These findings may be associated with hyperacusis after a sound-induced temporary threshold shift.

  2. Descending projections from auditory cortex to excitatory and inhibitory cells in the nucleus of the brachium of the inferior colliculus

    PubMed Central

    Mellott, Jeffrey G.; Bickford, Martha E.; Schofield, Brett R.

    2014-01-01

    Descending projections from the auditory cortex (AC) terminate in subcortical auditory centers from the medial geniculate nucleus (MG) to the cochlear nucleus, allowing the AC to modulate the processing of acoustic information at many levels of the auditory system. The nucleus of the brachium of the inferior colliculus (NBIC) is a large midbrain auditory nucleus that is a target of these descending cortical projections. The NBIC is a source of several auditory projections, including an ascending projection to the MG. This ascending projection appears to originate from both excitatory and inhibitory NBIC cells, but whether the cortical projections contact either of these cell groups is unknown. In this study, we first combined retrograde tracing and immunochemistry for glutamic acid decarboxylase (GAD, a marker of GABAergic cells) to identify GABAergic and non-GABAergic NBIC projections to the MG. Our first result is that GAD-immunopositive cells constitute ~17% of the NBIC to MG projection. We then used anterograde labeling and electron microscopy to examine the AC projection to the NBIC. Our second result is that cortical boutons in the NBIC form synapses with round vesicles and asymmetric synapses, consistent with excitatory effects. Finally, we combined fluorescent anterograde labeling of corticofugal axons with immunochemistry and retrograde labeling of NBIC cells that project to the MG. These final results suggest first that AC axons contact both GAD-negative and GAD-positive NBIC cells and, second, that some of cortically-contacted cells project to the MG. Overall, the results imply that corticofugal projections can modulate both excitatory and inhibitory ascending projections from the NBIC to the auditory thalamus. PMID:25339870

  3. FM velocity selectivity in the inferior colliculus is inherited from velocity-selective inputs and enhanced by spike threshold.

    PubMed

    Gittelman, Joshua X; Li, Na

    2011-11-01

    Frequency modulation (FM) is computed from the temporal sequence of activated auditory nerve fibers representing different frequencies. Most studies in the inferior colliculus (IC) have inferred from extracellular recordings that the precise timing of nonselective inputs creates selectivity for FM direction and velocity (Andoni S, Li N, Pollak GD. J Neurosci 27: 4882-4893, 2007; Fuzessery ZM, Richardson MD, Coburn MS. J Neurophysiol 96: 1320-1336, 2006; Gordon M, O'Neill WE. Hear Res 122: 97-108, 1998). We recently reported that two additional mechanisms were more important than input timing for directional selectivity in some IC cells: spike threshold and inputs that were already selective (Gittelman JX, Li N, Pollak GD. J Neurosci 29: 13030-13041, 2009). Here, we show that these same mechanisms, selective inputs and spike threshold, underlie selectivity for FM velocity and intensity. From whole cell recordings in awake bats, we recorded spikes and postsynaptic potentials (PSPs) evoked by downward and upward FMs that swept identical frequencies at different velocities and intensities. To determine the synaptic mechanisms underlying PSP selectivity (relative PSP height), we derived sweep-evoked synaptic conductances. Changing FM velocity or intensity changed conductance timing and size. Modeling indicated that excitatory conductance size contributed more to PSP selectivity than conductance timing, indicating that the number of afferent spikes carried more FM information to the IC than precise spike timing. However, excitation alone produced mostly suprathreshold PSPs. Inhibition reduced absolute PSP heights, without necessarily altering PSP selectivity, thereby rendering some PSPs subthreshold. Spike threshold then sharpened selectivity in the spikes by rectifying the smaller PSPs. This indicates the importance of spike threshold, and that inhibition enhances selectivity via a different mechanism than previously proposed.

  4. The effect of correlated neuronal firing and neuronal heterogeneity on population coding accuracy in guinea pig inferior colliculus.

    PubMed

    Zohar, Oran; Shackleton, Trevor M; Palmer, Alan R; Shamir, Maoz

    2013-01-01

    It has been suggested that the considerable noise in single-cell responses to a stimulus can be overcome by pooling information from a large population. Theoretical studies indicated that correlations in trial-to-trial fluctuations in the responses of different neurons may limit the improvement due to pooling. Subsequent theoretical studies have suggested that inherent neuronal diversity, i.e., the heterogeneity of tuning curves and other response properties of neurons preferentially tuned to the same stimulus, can provide a means to overcome this limit. Here we study the effect of spike-count correlations and the inherent neuronal heterogeneity on the ability to extract information from large neural populations. We use electrophysiological data from the guinea pig Inferior-Colliculus to capture inherent neuronal heterogeneity and single cell statistics, and introduce response correlations artificially. To this end, we generate pseudo-population responses, based on single-cell recording of neurons responding to auditory stimuli with varying binaural correlations. Typically, when pseudo-populations are generated from single cell data, the responses within the population are statistically independent. As a result, the information content of the population will increase indefinitely with its size. In contrast, here we apply a simple algorithm that enables us to generate pseudo-population responses with variable spike-count correlations. This enables us to study the effect of neuronal correlations on the accuracy of conventional rate codes. We show that in a homogenous population, in the presence of even low-level correlations, information content is bounded. In contrast, utilizing a simple linear readout, that takes into account the natural heterogeneity, even of neurons preferentially tuned to the same stimulus, within the neural population, one can overcome the correlated noise and obtain a readout whose accuracy grows linearly with the size of the population. PMID

  5. Differential roles of GABAergic and glycinergic input on FM selectivity in the inferior colliculus of the pallid bat.

    PubMed

    Williams, Anthony J; Fuzessery, Zoltan M

    2011-11-01

    Multiple mechanisms have been shown to shape frequency-modulated (FM) selectivity within the central nucleus of the inferior colliculus (IC) in the pallid bat. In this study we focus on the mechanisms associated with sideband inhibition. The relative arrival time of inhibition compared with excitation can be used to predict FM responses as measured with a two-tone inhibition paradigm. An early-arriving low-frequency inhibition (LFI) prevents responses to upward sweeps and thus shapes direction selectivity. A late-arriving high-frequency inhibition (HFI) suppresses slow FM sweeps and thus shapes rate selectivity for downward sweeps. Iontophoretic application of gabazine (GBZ) to block GABA(A) receptors or strychnine (Strych) to block glycine receptors was used to assess the effects of removal of inhibition on each form of FM selectivity. GBZ and Strych had a similar effect on FM direction selectivity, reducing selectivity in up to 86% of neurons when both drugs were coapplied. FM rate selectivity was more resistant to drug application with less than 38% of neurons affected. In addition, only Strych could eliminate FM rate selectivity, whereas GBZ alone was ineffective. The loss of FM selectivity was directly correlated to a loss of the respective inhibitory sideband that shapes that form of selectivity. The elimination of LFI correlated to a loss of FM direction selectivity, whereas elimination of HFI correlated to a loss of FM rate selectivity. Results indicate that 1) although the majority of FM direction selectivity is created within the IC, the majority of rate selectivity is inherited from lower levels of the auditory system, 2) a loss of LFI corresponds to a loss of FM direction selectivity and is created through either GABAergic or glycinergic input, and 3) a loss of HFI corresponds to a loss of FM rate selectivity and is created mainly through glycinergic input.

  6. Stimulation by cochlear implant in unilaterally deaf rats reverses the decrease of inhibitory transmission in the inferior colliculus.

    PubMed

    Argence, Meritxell; Vassias, Isabelle; Kerhuel, Lubin; Vidal, Pierre-Paul; de Waele, Catherine

    2008-10-01

    In the last decade, numerous studies have investigated synaptic transmission changes in various auditory nuclei after unilateral cochlear injury. However, few data are available concerning the potential effect of electrical stimulation of the deafferented auditory nerve on the inhibitory neurotransmission in these nuclei. We report here for the first time the effect of chronic electrical stimulation of the deafferented auditory nerve on alpha1 subunit of the glycinergic receptor (GlyRalpha1) and glutamic acid decarboxylase (GAD)67 expression in the central nucleus of inferior colliculus (CIC). Adult rats were unilaterally cochleectomized by intracochlear neomycin sulphate injection. Fifteen days later, the ipsilateral auditory nerve was chronically stimulated either 4, 8 or 22 h daily, for 5 days using intracochlear bipolar electrodes. GlyRalpha1 and GAD67 mRNA and protein were quantified in the CIC using in situ hybridization and immunohistofluorescence methods. Our data showed that as after surgical ablation, GlyRalpha1 and GAD67 expression were strongly decreased in the contralateral CIC after unilateral chemical cochleectomy. Most importantly, these postlesional down-modulations were significantly reversed by chronic electrical stimulation of the deafferented auditory nerve. This recovery, however, did not persist for more than 5 days after the cessation of the deafferented auditory nerve electrical stimulation. Thus, downregulations of GlyRalpha1 and GAD67 may be involved both in the increased excitability observed in the CIC after unilateral deafness and consequently in the tinnitus frequently observed in unilateral adult deaf patients. Electrical stimulation of the deafferented auditory nerve in patients may be a potential new approach for treating tinnitus with unilateral hearing loss. PMID:18973578

  7. Recovery cycle times of inferior colliculus neurons in the awake bat measured with spike counts and latencies

    PubMed Central

    Sayegh, Riziq; Aubie, Brandon; Fazel-Pour, Siavosh; Faure, Paul A.

    2012-01-01

    Neural responses in the mammalian auditory midbrain (inferior colliculus; IC) arise from complex interactions of synaptic excitation, inhibition, and intrinsic properties of the cell. Temporally selective duration-tuned neurons (DTNs) in the IC are hypothesized to arise through the convergence of excitatory and inhibitory synaptic inputs offset in time. Synaptic inhibition can be inferred from extracellular recordings by presenting pairs of pulses (paired tone stimulation) and comparing the evoked responses of the cell to each pulse. We obtained single unit recordings from the IC of the awake big brown bat (Eptesicus fuscus) and used paired tone stimulation to measure the recovery cycle times of DTNs and non-temporally selective auditory neurons. By systematically varying the interpulse interval (IPI) of the paired tone stimulus, we determined the minimum IPI required for a neuron's spike count or its spike latency (first- or last-spike latency) in response to the second tone to recover to within ≥50% of the cell's baseline count or to within 1 SD of it's baseline latency in response to the first tone. Recovery times of shortpass DTNs were significantly shorter than those of bandpass DTNs, and recovery times of bandpass DTNs were longer than allpass neurons not selective for stimulus duration. Recovery times measured with spike counts were positively correlated with those measured with spike latencies. Recovery times were also correlated with first-spike latency (FSL). These findings, combined with previous studies on duration tuning in the IC, suggest that persistent inhibition is a defining characteristic of DTNs. Herein, we discuss measuring recovery times of neurons with spike counts and latencies. We also highlight how persistent inhibition could determine neural recovery times and serve as a potential mechanism underlying the precedence effect in humans. Finally, we explore implications of recovery times for DTNs in the context of bat hearing and

  8. Roles of inhibition in creating complex auditory responses in the inferior colliculus: facilitated combination-sensitive neurons.

    PubMed

    Nataraj, Kiran; Wenstrup, Jeffrey J

    2005-06-01

    We studied roles of inhibition on temporally sensitive facilitation in combination-sensitive neurons from the mustached bat's inferior colliculus (IC). In these integrative neurons, excitatory responses to best frequency (BF) tones are enhanced by much lower frequency signals presented in a specific temporal relationship. Most facilitated neurons (76%) showed inhibition at delays earlier than or later than the delays causing facilitation. The timing of inhibition at earlier delays was closely related to the best delay of facilitation, but the inhibition had little influence on the duration or strength of the facilitatory interaction. Local iontophoretic application of antagonists to receptors for glycine (strychnine, STRY) and gamma-aminobutyric acid (GABA) (bicuculline, BIC) showed that STRY abolished facilitation in 96% of tested units, but BIC eliminated facilitation in only 28%. This suggests that facilitatory interactions are created in IC and reveals a differential role for these neurotransmitters. The facilitation may be created by coincidence of a postinhibitory rebound excitation activated by the low-frequency signal with the BF-evoked excitation. Unlike facilitation, inhibition at earlier delays was not eliminated by application of antagonists, suggesting an origin in lower brain stem nuclei. However, inhibition at delays later than facilitation, like facilitation itself, appears to originate within IC and to be more dependent on glycinergic than GABAergic mechanisms. Facilitatory and inhibitory interactions displayed by these combination-sensitive neurons encode information within sonar echoes and social vocalizations. The results indicate that these complex response properties arise through a series of neural interactions in the auditory brain stem and midbrain.

  9. A neural mechanism of phase-locked responses to sinusoidally amplitude-modulated signals in the inferior colliculus.

    PubMed

    Kato, Takayuki; Fujita, Kazuhisa; Kashimori, Yoshiki

    2015-08-01

    The central nucleus of the inferior colliculus (ICc) is an auditory region that receives convergent inputs from a large number of lower auditory nuclei. ICc neurons phase-lock to low frequencies of sinusoidally amplitude-modulated (SAM) signals but have a different mechanism in the phase-locking from that in neurons of lower nuclei. In the mustached bat, the phase-locking ability in lower nuclei is created by the coincidence of phase-locked excitatory and inhibitory inputs that have slightly different latencies. In contrast, the phase-locking property of ICc neurons is little influenced by the blocking of inhibitory synapses. Moreover, ICc neurons exhibit different characteristics in the spike patterns and synchronicity, classified here by three types of ICc neurons, or sustained, onset, and non-onset phase-locking neurons. However it remains unclear how ICc neurons create the phase-locking ability and the different characteristics. To address this issue, we developed a model of ICc neuronal population. Using this model, we show that the phase-locking ability of ICc neurons to low SAM frequencies is created by an intrinsic membrane property of ICc neuron, limited by inhibitory ion channels. We also show that response characteristics of the three types of neurons arise from the difference in an inhibitory effect sensitive to SAM frequencies. Our model reproduces well the experimental results observed in the mustached bat. These findings provide necessary conditions of how ICc neurons can give rise to the phase-locking ability and characteristic responses to low SAM frequencies. PMID:26032987

  10. Distribution of interaural time difference in the barn owl's inferior colliculus in the low- and high-frequency ranges.

    PubMed

    Wagner, Hermann; Asadollahi, Ali; Bremen, Peter; Endler, Frank; Vonderschen, Katrin; von Campenhausen, Mark

    2007-04-11

    Interaural time differences are an important cue for azimuthal sound localization. It is still unclear whether the same neuronal mechanisms underlie the representation in the brain of interaural time difference in different vertebrates and whether these mechanisms are driven by common constraints, such as optimal coding. Current sound localization models may be discriminated by studying the spectral distribution of response peaks in tuning curves that measure the sensitivity to interaural time difference. The sound localization system of the barn owl has been studied intensively, but data that would allow discrimination between currently discussed models are missing from this animal. We have therefore obtained extracellular recordings from the time-sensitive subnuclei of the barn owl's inferior colliculus. Response peaks were broadly scattered over the physiological range of interaural time differences. A change in the representation of the interaural phase differences with frequency was not observed. In some neurons, response peaks fell outside the physiological range of interaural time differences. For a considerable number of neurons, the peak closest to zero interaural time difference was not the behaviorally relevant peak. The data are in best accordance with models suggesting that a place code underlies the representation of interaural time difference. The data from the high-frequency range, but not from the low-frequency range, are consistent with predictions of optimal coding. We speculate that the deviation of the representation of interaural time difference from optimal-coding models in the low-frequency range is attributable to the diminished importance of low frequencies for catching prey in this species. PMID:17428997

  11. The immediate effects of acoustic trauma on excitation and inhibition in the inferior colliculus: A Wiener-kernel analysis.

    PubMed

    Heeringa, Amarins Nieske; van Dijk, Pim

    2016-01-01

    Noise-induced tinnitus and hyperacusis are thought to correspond to a disrupted balance between excitation and inhibition in the central auditory system. Excitation and inhibition are often studied using pure tones; however, these responses do not reveal inhibition within the excitatory pass band. Therefore, we used a Wiener-kernel analysis, complemented with singular value decomposition (SVD), to investigate the immediate effects of acoustic trauma on excitation and inhibition in the inferior colliculus (IC). Neural responses were recorded from the IC of three anesthetized albino guinea pigs before and immediately after a one-hour bilateral exposure to an 11-kHz tone of 124 dB SPL. Neural activity was recorded during the presentation of a 1-h continuous 70 dB SPL Gaussian-noise stimulus. Spike trains were subjected to Wiener-kernel analysis in which the second-order kernel was decomposed into excitatory and inhibitory components using SVD. Hearing thresholds between 3 and 22 kHz were elevated (13-47 dB) immediately after acoustic trauma. The presence and frequency tuning of excitation and inhibition in units with a low characteristic frequency (CF; < 3 kHz) was not affected, inhibition disappeared whereas excitation was not affected in mid-CF units (3 < CF < 11 kHz), and both excitation and inhibition disappeared in high-CF units (CF > 11 kHz). This specific differentiation could not be identified by tone-evoked receptive-field analysis, in which inhibitory responses disappeared in all units, along with excitatory responses in high-CF units. This study is the first to apply Wiener-kernel analysis, complemented with SVD, to study the effects of acoustic trauma on spike trains derived from the IC. With this analysis, a reduction of inhibition and preservation of good response thresholds was shown in mid-CF units immediately after acoustic trauma. These neurons may mediate noise-induced tinnitus and/or hyperacusis. Moreover, an immediate profound high

  12. Delay-tuned neurons in the inferior colliculus of the mustached bat: implications for analyses of target distance.

    PubMed

    Portfors, C V; Wenstrup, J J

    1999-09-01

    We examined response properties of delay-tuned neurons in the central nucleus of the inferior colliculus (ICC) of the mustached bat. In the mustached bat, delay-tuned neurons respond best to the combination of the first-harmonic, frequency-modulated (FM1) sweep in the emitted pulse and a higher harmonic frequency-modulated (FM2, FM3 or FM4) component in returning echoes and are referred to as FM-FM neurons. We also examined H1-CF2 neurons. H1-CF2 neurons responded to simultaneous presentation of the first harmonic (H1) in the emitted pulse and the second constant frequency (CF2) component in returning echoes. These neurons served as a comparison as they are thought to encode different features of sonar targets than FM-FM neurons. Only 7% of our neurons (14/198) displayed a single excitatory tuning curve. The rest of the neurons (184) displayed complex responses to sounds in two separate frequency bands. The majority (51%, 101) of neurons were facilitated by the combination of specific components in the mustached bat's vocalizations. Twenty-five percent showed purely inhibitory interactions. The remaining neurons responded to two separate frequencies, without any facilitation or inhibition. FM-FM neurons (69) were facilitated by the FM1 component in the simulated pulse and a higher harmonic FM component in simulated echoes, provided the high-frequency signal was delayed the appropriate amount. The delay producing maximal facilitation ("best delay") among FM-FM neurons ranged between 0 and 20 ms, corresponding to target distances

  13. Functional Microarchitecture of the Mouse Dorsal Inferior Colliculus Revealed through In Vivo Two-Photon Calcium Imaging

    PubMed Central

    Barnstedt, Oliver; Keating, Peter; Weissenberger, Yves

    2015-01-01

    The inferior colliculus (IC) is an obligatory relay for ascending auditory inputs from the brainstem and receives descending input from the auditory cortex. The IC comprises a central nucleus (CNIC), surrounded by several shell regions, but the internal organization of this midbrain nucleus remains incompletely understood. We used two-photon calcium imaging to study the functional microarchitecture of both neurons in the mouse dorsal IC and corticocollicular axons that terminate there. In contrast to previous electrophysiological studies, our approach revealed a clear functional distinction between the CNIC and the dorsal cortex of the IC (DCIC), suggesting that the mouse midbrain is more similar to that of other mammals than previously thought. We found that the DCIC comprises a thin sheet of neurons, sometimes extending barely 100 μm below the pial surface. The sound frequency representation in the DCIC approximated the mouse's full hearing range, whereas dorsal CNIC neurons almost exclusively preferred low frequencies. The response properties of neurons in these two regions were otherwise surprisingly similar, and the frequency tuning of DCIC neurons was only slightly broader than that of CNIC neurons. In several animals, frequency gradients were observed in the DCIC, and a comparable tonotopic arrangement was observed across the boutons of the corticocollicular axons, which form a dense mesh beneath the dorsal surface of the IC. Nevertheless, acoustically responsive corticocollicular boutons were sparse, produced unreliable responses, and were more broadly tuned than DCIC neurons, suggesting that they have a largely modulatory rather than driving influence on auditory midbrain neurons. SIGNIFICANCE STATEMENT Due to its genetic tractability, the mouse is fast becoming the most popular animal model for sensory neuroscience. Nevertheless, many aspects of its neural architecture are still poorly understood. Here, we image the dorsal auditory midbrain and its

  14. Neuroanatomical and neuropharmacological study of opioid pathways in the mesencephalic tectum: effect of mu(1)- and kappa-opioid receptor blockade on escape behavior induced by electrical stimulation of the inferior colliculus.

    PubMed

    Osaki, M Y; Castellan-Baldan, L; Calvo, F; Carvalho, A D; Felippotti, T T; de Oliveira, R; Ubiali, W A; Paschoalin-Maurin, T; Elias-Filho, D H; Motta, V; da Silva, L A; Coimbra, N C

    2003-12-01

    Deep layers of the superior colliculus (DLSC), the dorsal and ventral periaqueductal gray matter (PAG), and inferior colliculus (IC) are midbrain structures involved in the generation of defensive behavior. beta-Endorphin and Leu-enkephalin are some neurotransmitters that may modulate such behavior in mammals. Light microscopy immunocytochemistry with streptavidin method was used for the localization of the putative cells of defensive behavior with antibodies for endogenous opioids in rat brainstem. Midbrain structures showed positive neurons to beta-endorphin and Leu-enkephalin in similar distributions in the experimental animals, but we also noted the presence of varicose fibers positive to endogenous opioids in the PAG. Neuroanatomical techniques showed varicose fibers from the central nucleus of the inferior colliculus to ventral aspects of the PAG, at more caudal levels. Naloxonazine and nor-binaltorphimine, competitive antagonists that block mu(1)- and kappa-opioid receptors, were then used in the present work to investigate the involvement of opioid peptide neural system in the control of the fear-induced reactions evoked by electrical stimulation of the neural substrates of the inferior colliculus. The fear-like responses were measured by electrical stimulation of the central nucleus of the inferior colliculus, eliciting the escape behavior, which is characterized by vigorous running and jumping. Central administration of opioid antagonists (2.5 microg/0.2 microl and 5.0 microg/0.2 microl) was performed in non-anesthetized animals (Rattus norvegicus), and the behavioral manifestations of fear were registered after 10 min, 2 h, and 24 h of the pretreatment. Naloxonazine caused an increase of the defensive threshold, as compared to control, suggesting an antiaversive effect of the antagonism on mu(1)-opioid receptor. This finding was corroborated with central administration of nor-binaltorphimine, which also induced a decrease of the fear-like responses

  15. Functional organization of mustached bat inferior colliculus: I. Representation of FM frequency bands important for target ranging revealed by 14C-2-deoxyglucose autoradiography and single unit mapping.

    PubMed

    O'Neill, W E; Frisina, R D; Gooler, D M

    1989-06-01

    The representation in the inferior colliculus of the frequency modulated (FM) components of the first (25-30 kHz) and second (50-60 kHz) harmonic of the sonar signal of the mustached bat, which may be important for target range processing, was investigated by using the 2-deoxyglucose (2-DG) technique and single-unit mapping. In the 2-DG experiments, bats presented with second harmonic FM stimuli alone showed uptake of label in specific regions of the central nucleus and dorsal cortex of the inferior colliculus, and the nucleus of the brachium. In the central nucleus, a dorsoventrally and mediolaterally elongated slab at the caudal border of the anterolateral division was observed. Labeling in the dorsal cortex was contiguous with this band. Bats stimulated with pairs of first and second harmonic FM stimuli separated by short time delays showed similar patterns of labeling, with the addition of another dorsoventrally elongated region of uptake in the more rostral part of the anterolateral division, associated with label in the dorsal cortex. By comparison to control cases exposed to delayed pairs of first and third harmonic signals, or to a second harmonic constant-frequency tone burst at the bat's reference frequency (ca. 60 kHz), we deduced that this additional region of uptake was attributable to the first harmonic FM component. To elucidate further the details of the tonotopic organization and to correlate the frequency representation with anatomical features of the IC, fine-grained maps of single-unit best frequencies were obtained in the central nucleus. Isofrequency contours were reconstructed by computer from five bats after focal, iontophoretic injection of horseradish peroxidase to locate the penetrations and trace connections of the FM2 area. We found that the tissue volume representing FM2 frequencies (50-60 kHz) showed approximately a sixfold overrepresentation for this frequency band. This region occupied most of the caudal portion of the anterolateral

  16. Cortical Auditory Deafferentation Induces Long-Term Plasticity in the Inferior Colliculus of Adult Rats: Microarray and qPCR Analysis

    PubMed Central

    Clarkson, Cheryl; Herrero-Turrión, M. Javier; Merchán, Miguel A.

    2012-01-01

    The cortico-collicular pathway is a bilateral excitatory projection from the cortex to the inferior colliculus (IC). It is asymmetric and predominantly ipsilateral. Using microarrays and RT-qPCR we analyzed changes in gene expression in the IC after unilateral lesions of the auditory cortex, comparing the ICs ipsi- and contralateral to the lesioned side. At 15 days after surgery there were mainly changes in gene expression in the IC ipsilateral to the lesion. Regulation primarily involved inflammatory cascade genes, suggesting a direct effect of degeneration rather than a neuronal plastic reorganization. Ninety days after the cortical lesion the ipsilateral IC showed a significant up-regulation of genes involved in apoptosis and axonal regeneration combined with a down-regulation of genes involved in neurotransmission, synaptic growth, and gap junction assembly. In contrast, the contralateral IC at 90 days post-lesion showed an up-regulation in genes primarily related to neurotransmission, cell proliferation, and synaptic growth. There was also a down-regulation in autophagy and neuroprotection genes. These findings suggest that the reorganization in the IC after descending pathway deafferentation is a long-term process involving extensive changes in gene expression regulation. Regulated genes are involved in many different neuronal functions, and the number and gene rearrangement profile seems to depend on the density of loss of the auditory cortical inputs. PMID:23233834

  17. Effects of pulse phase duration and location of stimulation within the inferior colliculus on auditory cortical evoked potentials in a guinea pig model.

    PubMed

    Neuheiser, Anke; Lenarz, Minoo; Reuter, Guenter; Calixto, Roger; Nolte, Ingo; Lenarz, Thomas; Lim, Hubert H

    2010-12-01

    The auditory midbrain implant (AMI), which consists of a single shank array designed for stimulation within the central nucleus of the inferior colliculus (ICC), has been developed for deaf patients who cannot benefit from a cochlear implant. Currently, performance levels in clinical trials for the AMI are far from those achieved by the cochlear implant and vary dramatically across patients, in part due to stimulation location effects. As an initial step towards improving the AMI, we investigated how stimulation of different regions along the isofrequency domain of the ICC as well as varying pulse phase durations and levels affected auditory cortical activity in anesthetized guinea pigs. This study was motivated by the need to determine in which region to implant the single shank array within a three-dimensional ICC structure and what stimulus parameters to use in patients. Our findings indicate that complex and unfavorable cortical activation properties are elicited by stimulation of caudal-dorsal ICC regions with the AMI array. Our results also confirm the existence of different functional regions along the isofrequency domain of the ICC (i.e., a caudal-dorsal and a rostral-ventral region), which has been traditionally unclassified. Based on our study as well as previous animal and human AMI findings, we may need to deliver more complex stimuli than currently used in the AMI patients to effectively activate the caudal ICC or ensure that the single shank AMI is only implanted into a rostral-ventral ICC region in future patients.

  18. Early segregation of layered projections from the lateral superior olivary nucleus to the central nucleus of the inferior colliculus in the neonatal cat.

    PubMed

    Gabriele, Mark L; Shahmoradian, Sarah H; French, Christopher C; Henkel, Craig K; McHaffie, John G

    2007-10-10

    The central nucleus of the inferior colliculus (IC) is a laminated structure that receives multiple converging afferent projections. These projections terminate in a layered arrangement and are aligned with dendritic arbors of the predominant disc-shaped neurons, forming fibrodendritic laminae. Within this structural framework, inputs terminate in a precise manner, establishing a mosaic of partially overlapping domains that likely define functional compartments. Although several of these patterned inputs have been described in the adult, relatively little is known about their organization prior to hearing onset. The present study used the lipophilic carbocyanine dyes DiI and DiD to examine the ipsilateral and contralateral projections from the lateral superior olivary (LSO) nucleus to the IC in a developmental series of paraformaldehyde-fixed kitten tissue. By birth, the crossed and uncrossed projections had reached the IC and were distributed across the frequency axis of the central nucleus. At this earliest postnatal stage, projections already exhibited a characteristic banded arrangement similar to that described in the adult. The heaviest terminal fields of the two inputs were always complementary in nature, with the ipsilateral input appearing slightly denser. This early arrangement of interdigitating ipsilateral and contralateral LSO axonal bands that occupy adjacent sublayers supports the idea that the initial establishment of this highly organized mosaic of inputs that defines distinct synaptic domains within the IC occurs largely in the absence of auditory experience. Potential developmental mechanisms that may shape these highly ordered inputs prior to hearing onset are discussed.

  19. Dilation of the inferior colliculus and hypersensitivity to sound in Wnt1-cre and Wnt1-GAL4 double-transgenic mice.

    PubMed

    Nakajima, Mitsunari; Nishikawa, Chisa; Miyasaka, Yuki; Kikkawa, Yoshiaki; Mori, Hisamichi; Tsuruta, Momoko; Okuyama, Satoshi; Furukawa, Yoshiko

    2014-04-30

    The processing of sound information is mediated by the cochlea and the central auditory system. Among the central auditory system, the inferior colliculus (IC) has leading roles in the acoustic processing. In a previous study, we demonstrated psychiatric disorder-related behavioral abnormalities in a genetically modified animal of Wnt1-cre and Wnt1-GAL4 double-transgenic (dTg) mouse. Here we report an abnormal morphology of the IC and dysacusis in the dTg mice. The IC in the brain of the dTg mice is dilated in appearance and histologic analysis revealed a high cell-density in the IC. Also, the dTg mice showed high scores in a startle response test using a click box that emits a 20-kHz sound. Auditory brainstem response (ABR) test revealed lower ABR thresholds of the dTg mice at a test-stimulus frequency of 32kHz, but not at 4-16kHz. These findings suggest that the dTg mice could be a useful animal model for studying the physiologic function of the IC and the pathophysiology of psychiatric disorder-related dysacusis. PMID:24607930

  20. Experience-dependent plasticity in the inferior colliculus: a site for visual calibration of the neural representation of auditory space in the barn owl.

    PubMed

    Brainard, M S; Knudsen, E I

    1993-11-01

    The optic tectum (homolog of the superior colliculus) contains mutually aligned neural maps of auditory and visual space. During development, the organization of the auditory map is guided by spatial information provided by vision: barn owls raised wearing prismatic spectacles, which optically shift the visual field and the visual map in the optic tectum, develop an auditory map that is shifted by an approximately equivalent amount, such that alignment between the two maps is preserved (Knudsen and Brainard, 1991). In this study we investigated whether this shift in the auditory map is intrinsic to the optic tectum or whether it reflects plasticity at an earlier stage in the auditory pathway. Owls were raised wearing prismatic spectacles that displaced the visual field by 23 degrees to the left or right. This manipulation alters the normal correspondence between locations in the visual field and interaural time difference (ITD), the primary cue for the azimuth of a sound source. In normal owls and in owls with at least 150 d of prism experience, extracellular unit recordings were used to assess the representations of ITD at anatomically and physiologically defined sites in the optic tectum and in the two prior stages of the auditory pathway, the external and central nuclei of the inferior colliculus (ICx and ICc). In the optic tectum of normal owls, the values of ITD to which units responded most strongly (best ITDs) varied systematically with the azimuths of unit visual receptive fields (VRFs). In the prism-reared owls, best ITDs were shifted from normal toward the values of ITD produced by sounds at the locations of the units' optically displaced VRFs. In the ICx of prism-reared owls, the representation of ITD also was shifted from normal, by an amount and in a direction that could completely account for the shift in ITD measured in the optic tectum. At some sites in the ICx, the shift in ITD tuning was apparent within the first 7-8 msec of the response; shifted

  1. The sound source distance dependence of the acoustical cues to location and their encoding by neurons in the inferior colliculus: implications for the Duplex theory.

    PubMed

    Jones, Heath G; Koka, Kanthaiah; Thornton, Jennifer; Tollin, Daniel J

    2013-01-01

    For over a century, the Duplex theory has posited that low- and ­high-frequency sounds are localized using two different acoustical cues, interaural time (ITDs) and level (ILDs) differences, respectively. Psychophysical data have generally supported the theory for pure tones. Anatomically, ITDs and ILDs are separately encoded in two parallel brainstem pathways. Acoustically ILDs are a function of location and frequency such that lower and higher frequencies exhibit smaller and larger ILDs, respectively. It is well established that neurons throughout the auditory neuraxis encode high-frequency ILDs. Acoustically, low-frequency ILDs are negligible (∼1–2 dB); however, humans are still sensitive to them and physiological studies often report low-frequency ILD-sensitive neurons. These ­latter findings are at odds with the Duplex theory. We suggest that these discrepancies arise from an inadequate characterization of the acoustical environment. We hypothesize that low-frequency ILDs become large and useful when sources are located near the head. We tested this hypothesis by making measurements of the ILDs in chinchillas as a function of source distance and the sensitivity to ILDs in 103 neurons in the inferior colliculus (IC). The ILD sensitivity of IC neurons was found to be frequency independent even though far-field acoustical ILDs were frequency dependent. However, as source distance was decreased, the magnitudes of low-frequency ILDs increased. Using information theoretic methods, we ­demonstrate that a population of IC neurons can encode the full range of acoustic ILDs across frequency that would be experienced as a joint function of source location and distance. PMID:23716233

  2. Ephrin-B2 Reverse Signaling Is Required for Topography but Not Pattern Formation of Lateral Superior Olivary Inputs to the Inferior Colliculus

    PubMed Central

    Wallace, Matthew M.; Kavianpour, Sarah M.; Gabriele, Mark L.

    2014-01-01

    Graded and modular expressions of Eph-ephrins are known to provide positional information for the formation of topographic maps and patterning in the developing nervous system. Previously we have shown that ephrin-B2 is expressed in a continuous gradient across the tonotopic axis of the central nucleus of the inferior colliculus (CNIC), whereas patterns are discontinuous and modular in the lateral cortex of the IC (LCIC). The present study explores the involvement of ephrin-B2 signaling in the development of projections to the CNIC and LCIC arising from the lateral superior olivary nuclei (LSO) prior to hearing onset. Anterograde and retrograde fluorescent tracing methods in neonatal fixed tissue preparations were used to compare topographic mapping and the establishment of LSO layers/modules in wild-type and ephrin-B2lacZ/+ mice (severely compromised reverse signaling). At birth, pioneer LSO axons occupy the ipsilateral IC in both groups but are delayed contralaterally in ephrin-B2lacZ/+ mutants. By the onset of hearing, both wild-type and mutant projections form discernible layers bilaterally in the CNIC and modular arrangements within the ipsilateral LCIC. In contrast, ephrin-B2lacZ/+ mice lack a reliable topography in LSO-IC projections, suggesting that fully functional ephrin-B2 reverse signaling is required for normal projection mapping. Taken together, these ephrin-B2 findings paired with known coexpression of EphA4 suggest the importance of these signaling proteins in establishing functional auditory circuits prior to experience. PMID:23042409

  3. Organization and trade-off of spectro-temporal tuning properties of duration-tuned neurons in the mammalian inferior colliculus.

    PubMed

    Morrison, James A; Farzan, Faranak; Fremouw, Thane; Sayegh, Riziq; Covey, Ellen; Faure, Paul A

    2014-05-01

    Neurons throughout the mammalian central auditory pathway respond selectively to stimulus frequency and amplitude, and some are also selective for stimulus duration. First found in the auditory midbrain or inferior colliculus (IC), these duration-tuned neurons (DTNs) provide a potential neural mechanism for encoding temporal features of sound. In this study, we investigated how having an additional neural response filter, one selective to the duration of an auditory stimulus, influences frequency tuning and neural organization by recording single-unit responses and measuring the dorsal-ventral position and spectral-temporal tuning properties of auditory DTNs from the IC of the awake big brown bat (Eptesicus fuscus). Like other IC neurons, DTNs were tonotopically organized and had either V-shaped, U-shaped, or O-shaped frequency tuning curves (excitatory frequency response areas). We hypothesized there would be an interaction between frequency and duration tuning in DTNs, as electrical engineering theory for resonant filters dictates a trade-off in spectral-temporal resolution: sharp tuning in the frequency domain results in poorer resolution in the time domain and vice versa. While the IC is a more complex signal analyzer than an electrical filter, a similar operational trade-off could exist in the responses of DTNs. Our data revealed two patterns of spectro-temporal sensitivity and spatial organization within the IC: DTNs with sharp frequency tuning and broad duration tuning were located in the dorsal IC, whereas cells with wide spectral tuning and narrow temporal tuning were found in the ventral IC.

  4. Binaural neurons in the mustache bat's inferior colliculus. I. Responses of 60-kHz EI units to dichotic sound stimulation.

    PubMed

    Wenstrup, J J; Fuzessery, Z M; Pollak, G D

    1988-10-01

    1. Single-unit responses to closed-field, dichotic sound stimuli were obtained from EI neurons in the mustache bat's inferior colliculus; these neurons are excited by sound to the contralateral ear and inhibited by sound to the ipsilateral ear. All units were tuned to the 60-kHz component of the bat's sonar signal. The goal of the study was to describe basic features of the sensitivity to interaural intensity differences (IIDs) and sound intensity among an isofrequency population of EI neurons. The following paper describes how these features of IID sensitivity shape the response to free-field sounds. 2. Three features of IID sensitivity were considered. The inhibitory threshold (Figs. 1 and 2) described the IID at which inhibitory effects became pronounced; it was defined as the IID at which the excitatory response to contralateral sound was suppressed by 50%. Most units (68%) were inhibited at positive IID values, for which the ipsilateral (inhibitory) sound was more intense. The maximum inhibition (Figs. 1 and 3) described the strength of ipsilateral inhibition; it was defined as the percent that each unit was inhibited below its response to monaural stimulation of the contralateral ear. The majority of units (58%) were almost totally suppressed by a sufficiently intense ipsilateral sound. The IID range (Figs. 1 and 4) described the sharpness or slope of the IID cutoff; it was defined as the IID range over which the response changed from nearly unsuppressed (80% of maximum response) to near maximum suppression (20% of maximum response). Most units (71%) had IID ranges of less than or equal to 15 dB. 3. A significant correlation between the inhibitory threshold and the maximum inhibition (Fig. 5) among the sample of EI units suggests that some common neural mechanisms underlie these features of IID sensitivity. 4. The response of EI neurons to binaural stimuli was a function of sound intensity as well as IID (Fig. 7). In part, this resulted from intensity

  5. Alcohol Withdrawal-Induced Seizure Susceptibility is Associated with an Upregulation of CaV1.3 Channels in the Rat Inferior Colliculus

    PubMed Central

    Akinfiresoye, Luli R.; Allard, Joanne S.; Lovinger, David M.

    2015-01-01

    Background: We previously reported increased current density through L-type voltage-gated Ca2+ (CaV1) channels in inferior colliculus (IC) neurons during alcohol withdrawal. However, the molecular correlate of this increased CaV1 current is currently unknown. Methods: Rats received three daily doses of ethanol every 8 hours for 4 consecutive days; control rats received vehicle. The IC was dissected at various time intervals following alcohol withdrawal, and the mRNA and protein levels of the CaV1.3 and CaV1.2 α1 subunits were measured. In separate experiments, rats were tested for their susceptibility to alcohol withdrawal–induced seizures (AWS) 3, 24, and 48 hours after alcohol withdrawal. Results: In the alcohol-treated group, AWS were observed 24 hours after withdrawal; no seizures were observed at 3 or 48 hours. No seizures were observed at any time in the control-treated rats. Compared to control-treated rats, the mRNA level of the CaV1.3 α1 subunit was increased 1.4-fold, 1.9-fold, and 1.3-fold at 3, 24, and 48 hours, respectively. In contrast, the mRNA level of the CaV1.2 α1 subunit increased 1.5-fold and 1.4-fold at 24 and 48 hours, respectively. At 24 hours, Western blot analyses revealed that the levels of the CaV1.3 and CaV1.2 α1 subunits increased by 52% and 32%, respectively, 24 hours after alcohol withdrawal. In contrast, the CaV1.2 and CaV1.3 α1 subunits were not altered at either 3 or 48 hours during alcohol withdrawal. Conclusions: Expression of the CaV1.3 α1 subunit increased in parallel with AWS development, suggesting that altered L-type CaV1.3 channel expression is an important feature of AWS pathogenesis. PMID:25556199

  6. Encoding of the amplitude modulation of pulsatile electrical stimulation in the feline cochlear nucleus by neurons in the inferior colliculus; effects of stimulus pulse rate

    NASA Astrophysics Data System (ADS)

    McCreery, Douglas; Han, Martin; Pikov, Victor; Yadav, Kamal; Pannu, Satinderpall

    2013-10-01

    Objectives. Persons without a functional auditory nerve cannot benefit from cochlear implants, but some hearing can be restored by an auditory brainstem implant (ABI) with stimulating electrodes implanted on the surface of the cochlear nucleus (CN). Most users benefit from their ABI, but speech recognition tends to be poorer than for users of cochlear implants. Psychophysical studies suggest that poor modulation detection may contribute to the limited performance of ABI users. In a cat model, we determined how the pulse rate of the electrical stimulus applied within or on the CN affects temporal and rate encoding of amplitude modulation (AM) by neurons in the central nucleus of the inferior colliculus (ICC). Approach. Stimulating microelectrodes were implanted chronically in and on the cats' CN, and multi-site recording microelectrodes were implanted chronically into the ICC. Encoding of AM pulse trains by neurons in the ICC was characterized as vector strength (VS), the synchrony of neural activity with the AM, and as the mean rate of neuronal action potentials (neuronal spike rate (NSR)). Main results. For intranuclear microstimulation, encoding of AM as VS was up to 3 dB greater when stimulus pulse rate was increased from 250 to 500 pps, but only for neuronal units with low best acoustic frequencies, and when the electrical stimulation was modulated at low frequencies (10-20 Hz). For stimulation on the surface of the CN, VS was similar at 250 and 500 pps, and the dynamic range of the VS was reduced for pulse rates greater than 250 pps. Modulation depth was encoded strongly as VS when the maximum stimulus amplitude was held constant across a range of modulation depth. This ‘constant maximum’ protocol allows enhancement of modulation depth while preserving overall dynamic range. However, modulation depth was not encoded as strongly as NSR. Significance. The findings have implications for improved sound processors for present and future ABIs. The performance of

  7. Expression of tumor necrosis factor-α and interleukin-1β genes in the cochlea and inferior colliculus in salicylate-induced tinnitus

    PubMed Central

    2011-01-01

    Background Changes in the gene expressions for tumor necrosis factor-α (TNF-α) and/or interleukin-1β (IL-1β) during tinnitus have not been previously reported. We evaluated tinnitus and mRNA expression levels of TNF-α, IL-1β, and N-methyl D-aspartate receptor subunit 2B (NR2B) genes in cochlea and inferior colliculus (IC) of mice after intraperitoneal injections of salicylate. Methods Forty-eight 3-month-old male SAMP8 mice were randomly and equally divided into two groups: salicylate-treated and saline-treated. All mice were trained to perform an active avoidance task for 5 days. Once conditioned, an active avoidance task was performed 2 hours after daily intraperitoneal injections of saline, either alone or containing 300 mg/kg sodium salicylate. Total numbers of times (tinnitus score) the mice climbed during the inter-trial silent period for 10 trials were recorded daily for 4 days (days 7 to 10), and then mice were euthanized for determination of mRNA expression levels of TNF-α, IL-1β, and NR2B genes in cochlea and IC at day 10. Results Tinnitus scores increased in response to daily salicylate treatments. The mRNA expression levels of TNF-α increased significantly for the salicylate-treated group compared to the control group in both cochlea (1.89 ± 0.22 vs. 0.87 ± 0.07, P < 0.0001) and IC (2.12 ± 0.23 vs. 1.73 ± 0.22, p = 0.0040). mRNA expression levels for the IL-1β gene also increased significantly in the salicylate group compared to the control group in both cochlea (3.50 ± 1.05 vs. 2.80 ± 0.28, p < 0.0001) and IC (2.94 ± 0.51 versus 1.24 ± 0.52, p = 0.0013). Linear regression analysis revealed a significant positive association between tinnitus scores and expression levels of TNF-α, IL-1β, and NR2B genes in cochlea and IC. In addition, expression levels of the TNF-α gene were positively correlated with those of the NR2Bgene in both cochlea and IC; whereas, the expression levels of the IL-1β gene was positively correlated with that of

  8. Spontaneous colonic adenocarcinoma in marmosets.

    PubMed

    Lushbaugh, C C; Humason, G L; Swartzendruber, D C; Richter, C B; Gengozian, N

    1978-01-01

    We find that colonic adenocarcinoma, which is an extremely rare neoplasm of all animals except man and carcinogen-treated rodents, occurs spontaneously in some marmosets. The cotton-topped Saguinus oedipus oedipus is particularly prone to develop it, but we have found it also at necropsy in Callimico goeldii (Goeldi's marmoset). Numerous metastases to regional lymph nodes develop. The cancers arise de novo in the mucosa and early invade the submucosa and lymphatic apparatus and paracolonic lymph nodes. These findings and the continuing occurrence of this cancer in our colony suggests that the marmoset may be the long-sought primate model for experimental intestinal carcinogenesis.

  9. Projection from the accommodation-related area in the superior colliculus of the cat.

    PubMed

    Sato, A; Ohtsuka, K

    1996-04-01

    Our previous study has indicated that accommodative responses can be evoked with weak currents applied to a circumscribed area of the superior colliculus in the cat. We investigated efferent projections from this area with biocytin in the present study. The accommodation area in the superior colliculus was identified by systematic microstimulation in each of five anesthetized cats. Accommodative responses were detected by an infrared optometer. After mapping the superior colliculus, biocytin was injected through a glass micropipette into the accommodation area, where accommodative responses were elicited with low-intensity microstimulation. In addition, accommodative responses to stimulation of the superior colliculus were compared before and after an injection of muscimol, an agonist of inhibitory neurotransmitter, into the pretectum. Following the injection of biocytin, in the ascending projections, labeled terminals were seen mainly in the caudal portion of the nucleus of the optic tract, the nucleus of the posterior commissure, the posterior pretectal nucleus, the olivary pretectal nucleus, the mesencephalic reticular formation at the level of the oculomotor nucleus, and the lateral posterior nucleus of the thalamus on the ipsilateral side. Less dense terminals were seen in the anterior pretectal nucleus, the zona incerta, and the centromedian nucleus of the thalamus. In the descending projections, labeled terminals were observed mainly in the paramedian pontine reticular formation, the nucleus raphe interpositus, and the dorsomedial portion of the nucleus reticularis tegmenti pontis on the contralateral side. Less dense terminals were also seen in the nucleus of the brachium of the inferior colliculus, the cuneiform nucleus, the medial part of the paralemniscal tegmental field, and the dorsolateral division of the pontine nuclei on the ipsilateral side. Following the injection of muscimol into the pretectum, including the nucleus of the optic tract, the

  10. Effects of neonatal enucleation on the functional organization of the superior colliculus in the golden hamster.

    PubMed Central

    Rhoades, R W

    1980-01-01

    1. The responses of visual, auditory and somatosensory superior collicular neurones were investigated using extracellular single unit recording techniques in hamsters which were subjected to the removal of one eye on the day of birth. 2. Neonatal enucleation resulted in a marked increase in the region of the colliculus from which visual neurones activated by stimulation of the ipsilateral eye could be recorded. In most cases the visuotopic representation in the colliculus ipsilateral to the remaining eye mirrored that observed in the contralateral tectum along both the rostrocaudal and mediolateral axes: in both colliculi temporal retina projected rostrally and inferior retina medially. In some animals, however, there appeared to be a dual mapping of the remaining eye onto the ipsilateral tectum. In these hamsters the central portion of the visual field was represented twice along the rostrocaudal axis of colliculus. 3. No changes in the topography of the somatosensory and auditory representations in the tectum were observed following neonatal enucleation. 4. The laminar distribution of visual neurones in the ipsilateral colliculus was markedly altered in the neonatally enucleated hamsters. Very few exclusively visual units were encountered in the layers ventral to the stratum opticum and almost all of the visual cells recorded in the ipsilateral colliculus were isolated within 150 microM of the tectal surface. 5. In the posterior half of the ipsilateral tectum a large number of extravisually responsive cells were encountered in the stratum griseum superficiale and stratum opticum. This was not the case in the colliculus contralateral to the remaining eye, nor has it ever been observed in normal hamsters. 6. Recordings from animals subjected to both neonatal enucleation and acute bilateral removal of somatosensory and auditory cortex indicated that the projections from these areas to the colliculus were not essential to the observed changes in laminar organization

  11. Neurobehavioral Development of Common Marmoset Monkeys

    PubMed Central

    Schultz-Darken, Nancy; Braun, Katarina M.; Emborg, Marina E.

    2016-01-01

    Common marmoset (Callithrix jacchus) monkeys are a resource for biomedical research and their use is predicted to increase due to the suitability of this species for transgenic approaches. Identification of abnormal neurodevelopment due to genetic modification relies upon the comparison with validated patterns of normal behavior defined by unbiased methods. As scientists unfamiliar with nonhuman primate development are interested to apply genomic editing techniques in marmosets, it would be beneficial to the field that the investigators use validated methods of postnatal evaluation that are age and species appropriate. This review aims to analyze current available data on marmoset physical and behavioral postnatal development, describe the methods used and discuss next steps to better understand and evaluate marmoset normal and abnormal postnatal neurodevelopment PMID:26502294

  12. Influence of season on birth distribution in marmosets and tamarins.

    PubMed

    Brand, H M

    1980-10-01

    The cotton-topped tamarin in captivity exhibits a seasonal influence on birth distribution, while the captive silvery marmoset, common marmoset, Goeldi's monkey and red-mantled tamarin are not significantly affected.

  13. [Effect of destruction of the inferior colliculi on the performance of the echolocating system of horseshoe-nosed bats].

    PubMed

    Movchan, E V

    1980-01-01

    The effect of unilateral and bilateral destruction of the inferior colliculi on the auditory system sensitivity, sonar signals' parameters and the Doppler shift compensation in echoes was studied in horseshoe bats Rhinolophus ferrumequinum. Complete bilateral destruction of the inferior colliculi did not produce the auditory system disfunction, but it sharply decreased auditory sensitivity of this system which was manifested in a reduction of the maximum detection range and inability to detect a weakly sounding insect. The data obtained suggest that the inferior colliculi are immediately responsible for the maintenance of emitting frequency and that the role which various regions of inferior colliculus play in that process is different. To preserve the effect of the Doppler shift compensation it is necessary to keep intact not less than a half of the central nucleus at least of one inferior colliculus.

  14. Marmosets (Saguinus fuscicollis): Are Learning Sets Learned?

    PubMed

    Menzel, E W; Juno, C

    1982-08-20

    Confronted with a novel object, a social group of marmoset monkeys investigated it. If they found food on it they returned to it readily the next day; whoever had led in eating usually did so again. If they did not find food, day 2 responsiveness decreased. These untrained performances were sufficient for one-trial visual discrimination learning.

  15. Internal capsule stroke in the common marmoset.

    PubMed

    Puentes, S; Kaido, T; Hanakawa, T; Ichinohe, N; Otsuki, T; Seki, K

    2015-01-22

    White matter (WM) impairment and motor deficit after stroke are directly related. However, WM injury mechanisms and their relation to motor disturbances are still poorly understood. In humans, the anterior choroidal artery (AChA) irrigates the internal capsule (IC), and stroke to this region can induce isolated motor impairment. The goal of this study was to analyze whether AChA occlusion can injure the IC in the marmoset monkey. The vascular distribution of the marmoset brain was examined by colored latex perfusion and revealed high resemblance to the human brain anatomy. Next, a new approach to electrocoagulate the AChA was developed and chronic experiments showed infarction compromising the IC on magnetic resonance imaging (MRI) scanning (day 4) and histology (day 11). Behavioral analysis was performed using a neurologic score previously developed and our own scoring method. Marmosets showed a decreased score that was still evident at day 10 after AChA electrocoagulation. We developed a new approach able to induce damage to the marmoset IC that may be useful for the detailed study of WM impairment and behavioral changes after stroke in the nonhuman primate.

  16. Internal capsule stroke in the common marmoset.

    PubMed

    Puentes, S; Kaido, T; Hanakawa, T; Ichinohe, N; Otsuki, T; Seki, K

    2015-01-22

    White matter (WM) impairment and motor deficit after stroke are directly related. However, WM injury mechanisms and their relation to motor disturbances are still poorly understood. In humans, the anterior choroidal artery (AChA) irrigates the internal capsule (IC), and stroke to this region can induce isolated motor impairment. The goal of this study was to analyze whether AChA occlusion can injure the IC in the marmoset monkey. The vascular distribution of the marmoset brain was examined by colored latex perfusion and revealed high resemblance to the human brain anatomy. Next, a new approach to electrocoagulate the AChA was developed and chronic experiments showed infarction compromising the IC on magnetic resonance imaging (MRI) scanning (day 4) and histology (day 11). Behavioral analysis was performed using a neurologic score previously developed and our own scoring method. Marmosets showed a decreased score that was still evident at day 10 after AChA electrocoagulation. We developed a new approach able to induce damage to the marmoset IC that may be useful for the detailed study of WM impairment and behavioral changes after stroke in the nonhuman primate. PMID:25453768

  17. Motor Functions of the Superior Colliculus

    PubMed Central

    Gandhi, Neeraj J.; Katnani, Husam A.

    2013-01-01

    The mammalian superior colliculus (SC) and its nonmammalian homolog, the optic tectum, constitute a major node in processing sensory information, incorporating cognitive factors, and issuing motor commands. The resulting action—to orient toward or away from a stimulus—can be accomplished as an integrated movement across oculomotor, cephalomotor, and skeletomotor effectors. The SC also participates in preserving fixation during intersaccadic intervals. This review highlights the repertoire of movements attributed to SC function and analyzes the significance of results obtained from causality-based experiments (microstimulation and inactivation). The mechanisms potentially used to decode the population activity in the SC into an appropriate movement command are also discussed. PMID:21456962

  18. Marmosets: A Neuroscientific Model of Human Social Behavior.

    PubMed

    Miller, Cory T; Freiwald, Winrich A; Leopold, David A; Mitchell, Jude F; Silva, Afonso C; Wang, Xiaoqin

    2016-04-20

    The common marmoset (Callithrix jacchus) has garnered interest recently as a powerful model for the future of neuroscience research. Much of this excitement has centered on the species' reproductive biology and compatibility with gene editing techniques, which together have provided a path for transgenic marmosets to contribute to the study of disease as well as basic brain mechanisms. In step with technical advances is the need to establish experimental paradigms that optimally tap into the marmosets' behavioral and cognitive capacities. While conditioned task performance of a marmoset can compare unfavorably with rhesus monkey performance on conventional testing paradigms, marmosets' social behavior and cognition are more similar to that of humans. For example, marmosets are among only a handful of primates that, like humans, routinely pair bond and care cooperatively for their young. They are also notably pro-social and exhibit social cognitive abilities, such as imitation, that are rare outside of the Apes. In this Primer, we describe key facets of marmoset natural social behavior and demonstrate that emerging behavioral paradigms are well suited to isolate components of marmoset cognition that are highly relevant to humans. These approaches generally embrace natural behavior, which has been rare in conventional primate testing, and thus allow for a new consideration of neural mechanisms underlying primate social cognition and signaling. We anticipate that through parallel technical and paradigmatic advances, marmosets will become an essential model of human social behavior, including its dysfunction in neuropsychiatric disorders.

  19. Marmosets: A Neuroscientific Model of Human Social Behavior.

    PubMed

    Miller, Cory T; Freiwald, Winrich A; Leopold, David A; Mitchell, Jude F; Silva, Afonso C; Wang, Xiaoqin

    2016-04-20

    The common marmoset (Callithrix jacchus) has garnered interest recently as a powerful model for the future of neuroscience research. Much of this excitement has centered on the species' reproductive biology and compatibility with gene editing techniques, which together have provided a path for transgenic marmosets to contribute to the study of disease as well as basic brain mechanisms. In step with technical advances is the need to establish experimental paradigms that optimally tap into the marmosets' behavioral and cognitive capacities. While conditioned task performance of a marmoset can compare unfavorably with rhesus monkey performance on conventional testing paradigms, marmosets' social behavior and cognition are more similar to that of humans. For example, marmosets are among only a handful of primates that, like humans, routinely pair bond and care cooperatively for their young. They are also notably pro-social and exhibit social cognitive abilities, such as imitation, that are rare outside of the Apes. In this Primer, we describe key facets of marmoset natural social behavior and demonstrate that emerging behavioral paradigms are well suited to isolate components of marmoset cognition that are highly relevant to humans. These approaches generally embrace natural behavior, which has been rare in conventional primate testing, and thus allow for a new consideration of neural mechanisms underlying primate social cognition and signaling. We anticipate that through parallel technical and paradigmatic advances, marmosets will become an essential model of human social behavior, including its dysfunction in neuropsychiatric disorders. PMID:27100195

  20. Object permanence in common marmosets (Callithrix jacchus).

    PubMed

    Mendes, Natacha; Huber, Ludwig

    2004-03-01

    A series of 9 search tasks corresponding to the Piagetian Stages 3-6 of object permanence were administered to 11 common marmosets (Callithrix jacchus). Success rates varied strongly among tasks and marmosets, but the performances of most subjects were above chance level on the majority of tasks of visible and invisible displacements. Although up to 24 trials were administered in the tests, subjects did not improve their performance across trials. Errors were due to preferences for specific locations or boxes, simple search strategies, and attentional deficits. The performances of at least 2 subjects that achieved very high scores up to the successive invisible displacement task suggest that this species is able to represent the existence and the movements of unperceived objects.

  1. Cryopreservation of ovaries from neonatal marmoset monkeys

    PubMed Central

    Motohashi, Hideyuki H.; Ishibashi, Hidetoshi

    2016-01-01

    The ovary of neonatal nonhuman primates contains the highest number of immature oocytes, but its cryopreservation has not yet been sufficiently investigated in all life stages. In the current study, we investigated cryodamage after vitrification/warming of neonatal ovaries from a nonhuman primate, the common marmoset (Callithrix jacchus). A Cryotop was used for cryopreservation of whole ovaries. The morphology of the vitrified/warmed ovaries was found to be equivalent to that of fresh ovaries. No significant difference in the number of oocytes retaining normal morphology per unit area in histological sections was found between the two groups. In an analysis of dispersed cells from the ovaries, however, the cell viability of the vitrified/warmed group tended to be decreased. The results of a comet assay showed no significant differences in DNA damage. These results show that cryopreservation of neonatal marmoset ovaries using vitrification may be useful as a storage system for whole ovaries. PMID:26876597

  2. Viral Vector-Based Dissection of Marmoset GFAP Promoter in Mouse and Marmoset Brains

    PubMed Central

    Takahashi, Nobutaka; Matsuzaki, Yasunori; Kishi, Shoji; Hirai, Hirokazu

    2016-01-01

    Adeno-associated virus (AAV) vectors are small in diameter, diffuse easily in the brain, and represent a highly efficient means by which to transfer a transgene to the brain of a large animal. A major demerit of AAV vectors is their limited accommodation capacity for transgenes. Thus, a compact promoter is useful when delivering large transgenes via AAV vectors. In the present study, we aimed to identify the shortest astrocyte-specific GFAP promoter region that could be used for AAV-vector-mediated transgene expression in the marmoset brain. The 2.0-kb promoter region upstream of the GFAP gene was cloned from the marmoset genome, and short promoters (1.6 kb, 1.4 kb, 0.6 kb, 0.3 kb and 0.2 kb) were obtained by progressively deleting the original 2.0-kb promoter from the 5’ end. The short promoters were screened in the mouse cerebellum in terms of their strength and astrocyte specificity. We found that the 0.3-kb promoter maintained 40% of the strength of the original 2.0-kb promoter, and approximately 90% of its astrocyte specificity. These properties were superior to those of the 1.4-kb, 0.6-kb (20% promoter strength) and 0.2-kb (70% astrocyte specificity) promoters. Then, we verified whether the 0.3-kb GFAP promoter retained astrocyte specificity in the marmoset cerebral cortex. Injection of viral vectors carrying the 0.3-kb marmoset GFAP promoter specifically transduced astrocytes in both the cerebral cortex and cerebellar cortex of the marmoset. These results suggest that the compact 0.3-kb promoter region serves as an astrocyte-specific promoter in the marmoset brain, which permits us to express a large gene by AAV vectors that have a limited accommodation capacity. PMID:27571575

  3. Active Vision in Marmosets: A Model System for Visual Neuroscience

    PubMed Central

    Reynolds, John H.; Miller, Cory T.

    2014-01-01

    The common marmoset (Callithrix jacchus), a small-bodied New World primate, offers several advantages to complement vision research in larger primates. Studies in the anesthetized marmoset have detailed the anatomy and physiology of their visual system (Rosa et al., 2009) while studies of auditory and vocal processing have established their utility for awake and behaving neurophysiological investigations (Lu et al., 2001a,b; Eliades and Wang, 2008a,b; Osmanski and Wang, 2011; Remington et al., 2012). However, a critical unknown is whether marmosets can perform visual tasks under head restraint. This has been essential for studies in macaques, enabling both accurate eye tracking and head stabilization for neurophysiology. In one set of experiments we compared the free viewing behavior of head-fixed marmosets to that of macaques, and found that their saccadic behavior is comparable across a number of saccade metrics and that saccades target similar regions of interest including faces. In a second set of experiments we applied behavioral conditioning techniques to determine whether the marmoset could control fixation for liquid reward. Two marmosets could fixate a central point and ignore peripheral flashing stimuli, as needed for receptive field mapping. Both marmosets also performed an orientation discrimination task, exhibiting a saturating psychometric function with reliable performance and shorter reaction times for easier discriminations. These data suggest that the marmoset is a viable model for studies of active vision and its underlying neural mechanisms. PMID:24453311

  4. The adaptation of visual and auditory integration in the barn owl superior colliculus with Spike Timing Dependent Plasticity.

    PubMed

    Huo, Juan; Murray, Alan

    2009-09-01

    To localize a seen object, the superior colliculus of the barn owl integrates the visual and auditory localization cues which are accessed from the sensory system of the brain. These cues are formed as visual and auditory maps. The alignment between visual and auditory maps is very important for accurate localization in prey behavior. Blindness or prism wearing may interfere this alignment. The juvenile barn owl could adapt its auditory map to this mismatch after several weeks training. Here we investigate this process by building a computational model of auditory and visual integration in deep Superior Colliculus (SC). The adaptation of the map alignment is based on activity dependent axon developing in Inferior Colliculus (IC). This axon growing process is instructed by an inhibitory network in SC while the strength of the inhibition is adjusted by Spike Timing Dependent Plasticity (STDP). The simulation results of this model are in line with the biological experiment and support the idea that STDP is involved in the alignment of sensory maps. This model also provides a new spiking neuron based mechanism capable of eliminating the disparity in visual and auditory map integration. PMID:19084371

  5. Superior Colliculus and Visual Spatial Attention

    PubMed Central

    Krauzlis, Richard J.; Lovejoy, Lee P.; Zénon, Alexandre

    2013-01-01

    The superior colliculus (SC) has long been known to be part of the network of brain areas involved in spatial attention, but recent findings have dramatically refined our understanding of its functional role. The SC both implements the motor consequences of attention and plays a crucial role in the process of target selection that precedes movement. Moreover, even in the absence of overt orienting movements, SC activity is related to shifts of covert attention and is necessary for the normal control of spatial attention during perceptual judgments. The neuronal circuits that link the SC to spatial attention may include attention-related areas of the cerebral cortex, but recent results show that the SC's contribution involves mechanisms that operate independently of the established signatures of attention in visual cortex. These findings raise new issues and suggest novel possibilities for understanding the brain mechanisms that enable spatial attention. PMID:23682659

  6. Comparative anatomy of marmoset and mouse cortex from genomic expression.

    PubMed

    Mashiko, Hiromi; Yoshida, Aya C; Kikuchi, Satomi S; Niimi, Kimie; Takahashi, Eiki; Aruga, Jun; Okano, Hideyuki; Shimogori, Tomomi

    2012-04-11

    Advances in mouse neural circuit genetics, brain atlases, and behavioral assays provide a powerful system for modeling the genetic basis of cognition and psychiatric disease. However, a critical limitation of this approach is how to achieve concordance of mouse neurobiology with the ultimate goal of understanding the human brain. Previously, the common marmoset has shown promise as a genetic model system toward the linking of mouse and human studies. However, the advent of marmoset transgenic approaches will require an understanding of developmental principles in marmoset compared to mouse. In this study, we used gene expression analysis in marmoset brain to pose a series of fundamental questions on cortical development and evolution for direct comparison to existing mouse brain atlas expression data. Most genes showed reliable conservation of expression between marmoset and mouse. However, certain markers had strikingly divergent expression patterns. The lateral geniculate nucleus and pulvinar in the thalamus showed diversification of genetic organization between marmoset and mouse, suggesting they share some similarity. In contrast, gene expression patterns in early visual cortical areas showed marmoset-specific expression. In prefrontal cortex, some markers labeled architectonic areas and layers distinct between mouse and marmoset. Core hippocampus was conserved, while afferent areas showed divergence. Together, these results indicate that existing cortical areas are genetically conserved between marmoset and mouse, while differences in areal parcellation, afferent diversification, and layer complexity are associated with specific genes. Collectively, we propose that gene expression patterns in marmoset brain reveal important clues to the principles underlying the molecular evolution of cortical and cognitive expansion.

  7. Neural interactions in unilateral colliculus and between bilateral colliculi modulate auditory signal processing.

    PubMed

    Mei, Hui-Xian; Cheng, Liang; Chen, Qi-Cai

    2013-01-01

    In the auditory pathway, the inferior colliculus (IC) is a major center for temporal and spectral integration of auditory information. There are widespread neural interactions in unilateral (one) IC and between bilateral (two) ICs that could modulate auditory signal processing such as the amplitude and frequency selectivity of IC neurons. These neural interactions are either inhibitory or excitatory, and are mostly mediated by γ-aminobutyric acid (GABA) and glutamate, respectively. However, the majority of interactions are inhibitory while excitatory interactions are in the minority. Such unbalanced properties between excitatory and inhibitory projections have an important role in the formation of unilateral auditory dominance and sound location, and the neural interaction in one IC and between two ICs provide an adjustable and plastic modulation pattern for auditory signal processing.

  8. Neural interactions in unilateral colliculus and between bilateral colliculi modulate auditory signal processing

    PubMed Central

    Mei, Hui-Xian; Cheng, Liang; Chen, Qi-Cai

    2013-01-01

    In the auditory pathway, the inferior colliculus (IC) is a major center for temporal and spectral integration of auditory information. There are widespread neural interactions in unilateral (one) IC and between bilateral (two) ICs that could modulate auditory signal processing such as the amplitude and frequency selectivity of IC neurons. These neural interactions are either inhibitory or excitatory, and are mostly mediated by γ-aminobutyric acid (GABA) and glutamate, respectively. However, the majority of interactions are inhibitory while excitatory interactions are in the minority. Such unbalanced properties between excitatory and inhibitory projections have an important role in the formation of unilateral auditory dominance and sound location, and the neural interaction in one IC and between two ICs provide an adjustable and plastic modulation pattern for auditory signal processing. PMID:23626523

  9. Cognitive bias, hand preference and welfare of common marmosets.

    PubMed

    Gordon, Dianne J; Rogers, Lesley J

    2015-01-01

    Common marmosets (Callithrix jacchus) have hand preferences for grasping pieces of food and holding them while eating and these are stable throughout adult life. We report here that left-handed marmosets have negative cognitive bias compared to right-handed marmosets. Twelve marmosets were trained to expect a food reward from a bowl with a black lid and not from one with a white lid, or vice versa. In probe tests with ambiguous, grey-lidded bowls a left-handed group (N=7) were less likely to remove the lid to inspect the bowl than a right-handed group (N=5). This difference between left- and right-handed marmosets was not dependent on rate of learning, sex or age. In fact, hand-preference was not associated with rate of learning the task. Furthermore, retrospective examination of colony records of 39 marmosets revealed that more aggression was directed towards left- than right-handed marmosets. Hence, hand preference, which can be measured easily, could serve as an indicator of cognitive bias and may signal a need for particular care in laboratory environments. We explain the results by arguing that hand preference reflects more frequent (or dominant) use of the opposite hemisphere and this predisposes individuals to behave differently.

  10. The marmoset monkey as a model for visual neuroscience.

    PubMed

    Mitchell, Jude F; Leopold, David A

    2015-04-01

    The common marmoset (Callithrix jacchus) has been valuable as a primate model in biomedical research. Interest in this species has grown recently, in part due to the successful demonstration of transgenic marmosets. Here we examine the prospects of the marmoset model for visual neuroscience research, adopting a comparative framework to place the marmoset within a broader evolutionary context. The marmoset's small brain bears most of the organizational features of other primates, and its smooth surface offers practical advantages over the macaque for areal mapping, laminar electrode penetration, and two-photon and optical imaging. Behaviorally, marmosets are more limited at performing regimented psychophysical tasks, but do readily accept the head restraint that is necessary for accurate eye tracking and neurophysiology, and can perform simple discriminations. Their natural gaze behavior closely resembles that of other primates, with a tendency to focus on objects of social interest including faces. Their immaturity at birth and routine twinning also makes them ideal for the study of postnatal visual development. These experimental factors, together with the theoretical advantages inherent in comparing anatomy, physiology, and behavior across related species, make the marmoset an excellent model for visual neuroscience.

  11. Cognitive bias, hand preference and welfare of common marmosets.

    PubMed

    Gordon, Dianne J; Rogers, Lesley J

    2015-01-01

    Common marmosets (Callithrix jacchus) have hand preferences for grasping pieces of food and holding them while eating and these are stable throughout adult life. We report here that left-handed marmosets have negative cognitive bias compared to right-handed marmosets. Twelve marmosets were trained to expect a food reward from a bowl with a black lid and not from one with a white lid, or vice versa. In probe tests with ambiguous, grey-lidded bowls a left-handed group (N=7) were less likely to remove the lid to inspect the bowl than a right-handed group (N=5). This difference between left- and right-handed marmosets was not dependent on rate of learning, sex or age. In fact, hand-preference was not associated with rate of learning the task. Furthermore, retrospective examination of colony records of 39 marmosets revealed that more aggression was directed towards left- than right-handed marmosets. Hence, hand preference, which can be measured easily, could serve as an indicator of cognitive bias and may signal a need for particular care in laboratory environments. We explain the results by arguing that hand preference reflects more frequent (or dominant) use of the opposite hemisphere and this predisposes individuals to behave differently. PMID:25813746

  12. Accommodation and induced myopia in marmosets.

    PubMed

    Troilo, David; Quinn, Nicole; Baker, Kayla

    2007-04-01

    Accommodation may indirectly influence visually guided eye growth by affecting the retinal defocus signal used to guide growth. Specifically, increased lags of accommodation associated with low stimulus-response (S-R) function slopes will impose increased hyperopic blur on the retina and may induce axial elongation and myopia. The purpose of this study was (1) to measure accommodation in awake, free viewing marmosets and (2) compare accommodation behavior in marmosets before and after inducing different amounts of myopia with binocular spectacle lenses. In untreated marmosets, the average accommodation S-R slope approached one, but showed considerable inter-individual variability (mean+/-SD: 0.964+/-0.249 for monocular viewing; 0.895+/-0.235 for binocular viewing; monocular and binocular measures not significantly different). The monocular S-R slopes were significantly reduced following a period of lens rearing that produced axial myopia (change in slope=-0.30+/-0.30, p<.01) and the reduction in slope was proportional to the amount of myopia induced (p<.01). The S-R slopes measured either under monocular or binocular conditions before induction of myopia were not well correlated with the degree of myopia induced (monocular: r=-.240, p=.453; binocular: r=-.060, p=.824). These results support the hypothesis that the reduction in S-R slope in myopes is a consequence of the myopia induced. The alternative hypothesis-that low S-R slope increases susceptibility to the development of myopia--is not supported by the weak correlation between the pre-manipulation S-R slopes and the magnitude of the myopic shift.

  13. Head Rotation Detection in Marmoset Monkeys

    NASA Astrophysics Data System (ADS)

    Simhadri, Sravanthi

    Head movement is known to have the benefit of improving the accuracy of sound localization for humans and animals. Marmoset is a small bodied New World monkey species and it has become an emerging model for studying the auditory functions. This thesis aims to detect the horizontal and vertical rotation of head movement in marmoset monkeys. Experiments were conducted in a sound-attenuated acoustic chamber. Head movement of marmoset monkey was studied under various auditory and visual stimulation conditions. With increasing complexity, these conditions are (1) idle, (2) sound-alone, (3) sound and visual signals, and (4) alert signal by opening and closing of the chamber door. All of these conditions were tested with either house light on or off. Infra-red camera with a frame rate of 90 Hz was used to capture of the head movement of monkeys. To assist the signal detection, two circular markers were attached to the top of monkey head. The data analysis used an image-based marker detection scheme. Images were processed using the Computation Vision Toolbox in Matlab. The markers and their positions were detected using blob detection techniques. Based on the frame-by-frame information of marker positions, the angular position, velocity and acceleration were extracted in horizontal and vertical planes. Adaptive Otsu Thresholding, Kalman filtering and bound setting for marker properties were used to overcome a number of challenges encountered during this analysis, such as finding image segmentation threshold, continuously tracking markers during large head movement, and false alarm detection. The results show that the blob detection method together with Kalman filtering yielded better performances than other image based techniques like optical flow and SURF features .The median of the maximal head turn in the horizontal plane was in the range of 20 to 70 degrees and the median of the maximal velocity in horizontal plane was in the range of a few hundreds of degrees per

  14. Geometrical gaze following in common marmosets (Callithrix jacchus).

    PubMed

    Burkart, Judith; Heschl, Adolf

    2006-05-01

    A series of experiments investigating the degree of gaze understanding in common marmosets (Callithrix jacchus) is reported. Results show that marmosets follow the gaze of a human experimenter readily and also use the gaze to locate food in a modified version of the object choice task if influences of chance probabilities and prepotent response tendencies are controlled for. In addition, this new version of the task allows the assessment of the accuracy of gaze following. Marmosets precisely extrapolate gaze direction, past distracting objects and from considerable distances, thereby meeting the criteria of so-called geometrical gaze following. The presence of this ability in common marmosets suggests that higher forms of gaze following might be more widely distributed among nonhuman primates than previously thought.

  15. Vocal Development: How Marmoset Infants Express Their Feelings.

    PubMed

    Tchernichovski, Ofer; Oller, D Kimbrough

    2016-05-23

    A new study shows that vocal sequences produced by newborn marmoset monkeys are driven by slow fluctuations in physiological state; the results shed light on the evolution of vocal communication between newborns and parents. PMID:27218851

  16. Vocal premotor activity in the superior colliculus.

    PubMed

    Sinha, Shiva R; Moss, Cynthia F

    2007-01-01

    Chronic neural recordings were taken from the midbrain superior colliculus (SC) of echolocating bats while they were engaged in one of two distinct behavioral tasks: virtual target amplitude discrimination (VTAD) and real oscillating target tracking (ROTT). In the VTAD task, bats used a limited range of sonar call features to discriminate the amplitude category of echoes, whereas in the ROTT task, the bat produced dynamically modulated sonar calls to track a moving target. Newly developed methods for chronic recordings in unrestrained, behaving bats reveal two consistent bouts of SC neural activity preceding the onset of sonar vocalizations in both tasks. A short lead bout occurs tightly coupled to vocal onset (VTAD, -5.1 to -2.2 ms range, -3.6 +/- 0.7 ms mean lead time; ROTT, -3.0 to + 0.4 ms range, -1.2 +/- 1.3 ms mean lead time), and this activity may play a role in marking the time of each sonar emission. A long lead bout in SC activity occurs earlier and spreads over a longer interval (VTAD, -40.6 to -8.4 ms range, -22.2 +/- 3.9 ms mean lead time; ROTT, -29.8 to -7.1 ms range, -17.5 +/- 9.1 ms mean lead time) when compared with short lead events. In the goal-directed ROTT task, the timing of long lead event times vary with the bat's sonar call duration. This finding, along with behavioral studies demonstrating that bats adjust sonar call duration as they track targets at changing distance, suggests the bat SC contributes to range-dependent adjustments of sonar call duration. PMID:17202477

  17. Vocal premotor activity in the superior colliculus.

    PubMed

    Sinha, Shiva R; Moss, Cynthia F

    2007-01-01

    Chronic neural recordings were taken from the midbrain superior colliculus (SC) of echolocating bats while they were engaged in one of two distinct behavioral tasks: virtual target amplitude discrimination (VTAD) and real oscillating target tracking (ROTT). In the VTAD task, bats used a limited range of sonar call features to discriminate the amplitude category of echoes, whereas in the ROTT task, the bat produced dynamically modulated sonar calls to track a moving target. Newly developed methods for chronic recordings in unrestrained, behaving bats reveal two consistent bouts of SC neural activity preceding the onset of sonar vocalizations in both tasks. A short lead bout occurs tightly coupled to vocal onset (VTAD, -5.1 to -2.2 ms range, -3.6 +/- 0.7 ms mean lead time; ROTT, -3.0 to + 0.4 ms range, -1.2 +/- 1.3 ms mean lead time), and this activity may play a role in marking the time of each sonar emission. A long lead bout in SC activity occurs earlier and spreads over a longer interval (VTAD, -40.6 to -8.4 ms range, -22.2 +/- 3.9 ms mean lead time; ROTT, -29.8 to -7.1 ms range, -17.5 +/- 9.1 ms mean lead time) when compared with short lead events. In the goal-directed ROTT task, the timing of long lead event times vary with the bat's sonar call duration. This finding, along with behavioral studies demonstrating that bats adjust sonar call duration as they track targets at changing distance, suggests the bat SC contributes to range-dependent adjustments of sonar call duration.

  18. Pentatrichomonas hominis in laboratory-bred common marmosets

    PubMed Central

    Inoue, Takashi; Hayashimoto, Nobuhito; Yasuda, Masahiko; Sasaki, Erika; Itoh, Toshio

    2015-01-01

    Trichomonadid protozoa have been found in the intestinal tracts of common marmosets (Callithrix jacchus). However, there is little information available on species identification and the pathogenicity of these trichomonads. In this study, we conducted a fecal survey of a common marmoset colony maintained as laboratory animals in Japan and identified the trichomonad species. Screening using a fecal smear examination revealed that 66% (58/88) of the marmosets had trichomonadid trophozoites in their feces. The trichomonads were found in both normal feces (31/49, 63%) and diarrhea (27/39, 69%), with no significant difference in frequency. The protozoa were identified as Pentatrichomonas hominis using morphological characters and the 100% identity of the nucleotide sequence of the partial 18S rRNA gene (297 bp). The intraspecific genetic variability between P. hominis from the marmosets in this study and P. hominis from other reported mammal hosts was ≤1% in the nucleotide sequence, including the internal transcribed spacer (ITS)-1, 5.8S rRNA gene, and ITS-2 (293 bp). P. hominis inhabits the large intestine of various mammalian hosts, including primates, and is considered nonpathogenic. These results suggest that P. hominis is transmitted among marmosets and other mammals but is not a primary cause of bowel disease in marmosets. PMID:26156572

  19. The marmoset monkey as a model for visual neuroscience

    PubMed Central

    Mitchell, Jude F.; Leopold, David A.

    2015-01-01

    The common marmoset (Callithrix jacchus) has been valuable as a primate model in biomedical research. Interest in this species has grown recently, in part due to the successful demonstration of transgenic marmosets. Here we examine the prospects of the marmoset model for visual neuroscience research, adopting a comparative framework to place the marmoset within a broader evolutionary context. The marmoset’s small brain bears most of the organizational features of other primates, and its smooth surface offers practical advantages over the macaque for areal mapping, laminar electrode penetration, and two-photon and optical imaging. Behaviorally, marmosets are more limited at performing regimented psychophysical tasks, but do readily accept the head restraint that is necessary for accurate eye tracking and neurophysiology, and can perform simple discriminations. Their natural gaze behavior closely resembles that of other primates, with a tendency to focus on objects of social interest including faces. Their immaturity at birth and routine twinning also makes them ideal for the study of postnatal visual development. These experimental factors, together with the theoretical advantages inherent in comparing anatomy, physiology, and behavior across related species, make the marmoset an excellent model for visual neuroscience. PMID:25683292

  20. Bone Disease in the Common Marmoset: Radiographic and Histological Findings.

    PubMed

    Olson, E J; Shaw, G C; Hutchinson, E K; Schultz-Darken, N; Bolton, I D; Parker, J B; Morrison, J M; Baxter, V K; Pate, K A Metcalf; Mankowski, J L; Carlson, C S

    2015-09-01

    The common marmoset (Callithrix jacchus) is a New World primate that is used in biomedical research due to its small size and relative ease of handling compared with larger primates. Although bone disease in common marmosets is well recognized, there are very few detailed descriptions in the literature that cover the range of lesions seen in these animals. For all animals used to model human disease, it is important to be aware of background lesions that may affect the interpretation of study findings. This retrospective study details bone diseases encountered in marmoset breeding colonies at 2 different institutions. Affected marmosets at Johns Hopkins University had lesions compatible with diagnoses of rickets, fibrous osteodystrophy and osteopenia. Affected marmosets at the Wisconsin National Primate Research Center exhibited severe lesions of osteoclastic bone resorption and remodeling that had an unusual distribution and were not easily categorized into a known disease entity. The purpose of this report is to document these naturally occurring skeletal lesions of common marmosets and suggest an approach to evaluating skeletal disease in prospective studies of these animals that will allow the most accurate diagnoses.

  1. Neural correlates of active avoidance behavior in superior colliculus

    PubMed Central

    Cohen, Jeremy D.; Castro-Alamancos, Manuel A.

    2010-01-01

    Active avoidance of harmful situations seems highly adaptive, but the underlying neural mechanisms are largely unknown. Rats can effectively use the superior colliculus during active avoidance to detect a salient whisker conditioned stimulus (WCS) that signals an aversive event. Here, we recorded unit and field potential activity in the intermediate layers of the superior colliculus of rats during active avoidance behavior. During the period preceding the onset of the WCS, avoids are associated with a higher firing rate than escapes (unsuccessful avoids), indicating that a prepared superior colliculus is more likely to detect the WCS and lead to an avoid. Moreover, during the WCS, a robust ramping up of overall firing rate is observed for trials leading to avoids. The firing rate ramping is not due to shuttling, and may serve to drive downstream circuits to avoid. Therefore, a robust neural correlate of active avoidance behavior is found in the superior colliculus, emphasizing its role in the detection of salient sensory signals that require immediate action. PMID:20573897

  2. Bilateral inferior turbinate osteoma

    PubMed Central

    Sahemey, R.; Warfield, A.T.; Ahmed, S.

    2016-01-01

    Osteomas are the most common benign osteoclastic tumours of the paranasal sinuses. However, nasal cavity and turbinate osteomas are extremely rare. Only nine middle turbinate, three inferior turbinate and one inferior turbinate osteoma cases have been reported to date. The present case report describes the management and follow-up of symptomatic bilateral inferior turbinate osteoma. A 60-year-old female presented with symptoms of bilateral nasal obstruction and right-sided epiphora. Radiological investigation found hypertrophic bony changes involving both inferior turbinates. The patient was managed successfully by endoscopic inferior turbinectomies in order to achieve a patent airway, with no further recurrence of tumour after 3 months postoperatively. To the best of our knowledge, this is the first reported case of bilateral inferior turbinate osteoma. We describe a safe and minimally invasive method of tumour resection, which has a better cosmetic outcome compared with other approaches. PMID:27534890

  3. Bilateral inferior turbinate osteoma.

    PubMed

    Sahemey, R; Warfield, A T; Ahmed, S

    2016-01-01

    Osteomas are the most common benign osteoclastic tumours of the paranasal sinuses. However, nasal cavity and turbinate osteomas are extremely rare. Only nine middle turbinate, three inferior turbinate and one inferior turbinate osteoma cases have been reported to date. The present case report describes the management and follow-up of symptomatic bilateral inferior turbinate osteoma.A 60-year-old female presented with symptoms of bilateral nasal obstruction and right-sided epiphora. Radiological investigation found hypertrophic bony changes involving both inferior turbinates. The patient was managed successfully by endoscopic inferior turbinectomies in order to achieve a patent airway, with no further recurrence of tumour after 3 months postoperatively.To the best of our knowledge, this is the first reported case of bilateral inferior turbinate osteoma. We describe a safe and minimally invasive method of tumour resection, which has a better cosmetic outcome compared with other approaches. PMID:27534890

  4. Marmosets as model species in neuroscience and evolutionary anthropology.

    PubMed

    Burkart, Judith M; Finkenwirth, Christa

    2015-04-01

    Marmosets are increasingly used as model species by both neuroscientists and evolutionary anthropologists, but with a different rationale for doing so. Whereas neuroscientists stress that marmosets share many cognitive traits with humans due to common descent, anthropologists stress those traits shared with marmosets - and callitrichid monkeys in general - due to convergent evolution, as a consequence of the cooperative breeding system that characterizes both humans and callitrichids. Similarities in socio-cognitive abilities due to convergence, rather than homology, raise the question whether these similarities also extend to the proximate regulatory mechanisms, which is particularly relevant for neuroscientific investigations. In this review, we first provide an overview of the convergent adaptations to cooperative breeding at the psychological and cognitive level in primates, which bear important implications for our understanding of human cognitive evolution. In the second part, we zoom in on two of these convergent adaptations, proactive prosociality and social learning, and compare their proximate regulation in marmosets and humans with regard to oxytocin and cognitive top down regulation. Our analysis suggests considerable similarity in these regulatory mechanisms presumably because the convergent traits emerged due to small motivational changes that define how pre-existing cognitive mechanisms are quantitatively combined. This finding reconciles the prima facie contradictory rationale for using marmosets as high priority model species in neuroscience and anthropology.

  5. Pregnancy weight gain: marmoset and tamarin dads show it too

    PubMed Central

    Ziegler, Toni E; Prudom, Shelley L; Schultz-Darken, Nancy J; Kurian, Aimee V; Snowdon, Charles T

    2006-01-01

    Paternal behaviour is critical for the survival of offspring in many monogamous species. Common marmoset (Callithrix jacchus) and cotton-top tamarin (Saguinus oedipus) fathers spend as much or more time caring for infants than mothers. Expectant males of both species showed significant increases in weight across the pregnancy whereas control males did not (five consecutive months for marmoset males and six months for cotton-top tamarin males). Expectant fathers might be preparing for the energetic cost of fatherhood by gaining weight during their mate's pregnancy. PMID:16810338

  6. Electrophysiologic Responses in Hamster Superior Colliculus Evoked by Regenerating Retinal Axons

    NASA Astrophysics Data System (ADS)

    Keirstead, S. A.; Rasminsky, M.; Fukuda, Y.; Carter, D. A.; Aguayo, A. J.; Vidal-Sanz, M.

    1989-10-01

    Autologous peripheral nerve grafts were used to permit and direct the regrowth of retinal ganglion cell axons from the eye to the ipsilateral superior colliculus of adult hamsters in which the optic nerves had been transected within the orbit. Extracellular recordings in the superior colliculus 15 to 18 weeks after graft insertion revealed excitatory and inhibitory postsynaptic responses to visual stimulation. The finding of light-induced responses in neurons in the superficial layers of the superior colliculus close to the graft indicates that axons regenerating from axotomized retinal ganglion cells can establish electrophysiologically functional synapses with neurons in the superior colliculus of these adult mammals.

  7. Controlled movement processing: superior colliculus activity associated with countermanded saccades.

    PubMed

    Paré, Martin; Hanes, Doug P

    2003-07-23

    We investigated whether the monkey superior colliculus (SC), an important midbrain structure for the regulation of saccadic eye movements, contains neurons with activity patterns sufficient to control both the cancellation and the production of saccades. We used a countermanding task to manipulate the probability that, after the presentation of a stop signal, the monkeys canceled a saccade that was planned in response to an eccentric visual stimulus. By modeling each animal's behavioral responses, with a race between GO and STOP processes leading up to either saccade initiation or cancellation, we estimated that saccade cancellation took on average 110 msec. Neurons recorded in the superior colliculus intermediate layers during this task exhibited the discharge properties expected from neurons closely involved in behavioral control. Both saccade- and fixation-related discharged differently when saccades were counter-manded instead of executed, and the time at which they changed their activity preceded the behavioral estimate of saccade cancellation obtained from the same trials by 10 and 13 msec, respectively. Furthermore, these intervals exceed the minimal amount of time needed for SC activity to influence eye movements. The additional observation that saccade-related neurons discharged significantly less when saccades were countermanded instead of executed suggests that saccades are triggered when these neurons reach a critical activation level. Altogether, these findings provide solid evidence that the superior colliculus contains the necessary neural signals to be directly involved in the decision process that regulates whether a saccade is to be produced.

  8. Controlled movement processing: superior colliculus activity associated with countermanded saccades.

    PubMed

    Paré, Martin; Hanes, Doug P

    2003-07-23

    We investigated whether the monkey superior colliculus (SC), an important midbrain structure for the regulation of saccadic eye movements, contains neurons with activity patterns sufficient to control both the cancellation and the production of saccades. We used a countermanding task to manipulate the probability that, after the presentation of a stop signal, the monkeys canceled a saccade that was planned in response to an eccentric visual stimulus. By modeling each animal's behavioral responses, with a race between GO and STOP processes leading up to either saccade initiation or cancellation, we estimated that saccade cancellation took on average 110 msec. Neurons recorded in the superior colliculus intermediate layers during this task exhibited the discharge properties expected from neurons closely involved in behavioral control. Both saccade- and fixation-related discharged differently when saccades were counter-manded instead of executed, and the time at which they changed their activity preceded the behavioral estimate of saccade cancellation obtained from the same trials by 10 and 13 msec, respectively. Furthermore, these intervals exceed the minimal amount of time needed for SC activity to influence eye movements. The additional observation that saccade-related neurons discharged significantly less when saccades were countermanded instead of executed suggests that saccades are triggered when these neurons reach a critical activation level. Altogether, these findings provide solid evidence that the superior colliculus contains the necessary neural signals to be directly involved in the decision process that regulates whether a saccade is to be produced. PMID:12878689

  9. Connections of the superior colliculus with the tegmentum and the cerebellum in the hedgehog tenrec.

    PubMed

    Künzle, H

    1997-06-01

    Different tracer substances were injected into the superior colliculus (CoS) in order to study its afferents and efferents with the meso-rhombencephalic tegmentum, the precerebellar nuclei and the cerebellum in the Madagascan hedgehog tenrec. The overall pattern of tectal connectivity in tenrec was similar to that in other mammals, as, e.g. the efferents to the contralateral paramedian reticular formation. Similarly the origin of the cerebello-tectal projection in mainly the lateral portions of the tenrec's cerebellar nuclear complex corresponded to the findings in species with little binocular overlap. In comparison to other mammals, however, the tenrec showed a consistent projection to the ipsilateral inferior olivary nucleus, in addition to the classical contralateral tecto-olivary projection. The tenrec's CoS also appeared to receive an unusually prominent monoaminergic input particularly from the substantia nigra, pars compacta. There was a reciprocal tecto-parabigeminal projection, a distinct nuclear aggregation of parabigeminal neurons, however, was difficult to identify. The dorsal lemniscal nucleus did not show perikaryal labeling in contrast to the paralemniscal region. Similar to the cat but unlike the rat there were a few neurons in the nucleus of the central acoustic tract. Unlike the cat, but similar to the rat there was a distinct, predominantly ipsilateral projection to the magnocellular reticular field known to project spinalward.

  10. Rabies in marmosets (Callithrix jacchus), Ceará, Brazil.

    PubMed Central

    Favoretto, S. R.; de Mattos, C. C.; Morais, N. B.; Alves Araújo, F. A.; de Mattos, C. A.

    2001-01-01

    A new Rabies virus variant, with no close antigenic or genetic relationship to any known rabies variants found in bats or terrestrial mammals in the Americas, was identified in association with human rabies cases reported from the state of Ceará, Brazil, from 1991 to 1998. The marmoset, Callithrix jacchus acchus, was determined to be the source of exposure. PMID:11747745

  11. Individual recognition during bouts of antiphonal calling in common marmosets

    PubMed Central

    Miller, Cory T.; Thomas, A. Wren

    2013-01-01

    Many vocalizations are encoded with a diversity of acoustic information about the signal producer. Amongst this information content are social categories related to the identity of the caller that are important for determining if and how a signal receiver may interact with that individual. Here we employed a novel playback method in common marmosets (Callithrix jacchus) to test individual recognition during bouts of antiphonal calling. These experiments utilized custom, interactive playback software that effectively engaged subjects in antiphonal calling using vocalizations produced by a single individual and presented ‘probe’ vocalization stimuli representing a different individual at specific points within bouts of calling. The aim here was to test whether marmosets would recognize that the probe stimulus was a phee call produced by a different individual. Data indicated that marmosets were able to detect the change in caller identity; subjects produced significantly fewer antiphonal call responses to probe than control stimuli and, in some conditions, exhibited a shorter latency to produce the vocal response. These data suggest that marmosets recognize the identity of the individual during bouts of antiphonal calling. Furthermore, these results provide a methodological foundation for implementing the probe playback procedure to examine a broader range of social categorization during vocal interactions. PMID:22277952

  12. Optogenetic manipulation of neural circuits in awake marmosets.

    PubMed

    MacDougall, Matthew; Nummela, Samuel U; Coop, Shanna; Disney, Anita; Mitchell, Jude F; Miller, Cory T

    2016-09-01

    Optogenetics has revolutionized the study of functional neuronal circuitry (Boyden ES, Zhang F, Bamberg E, Nagel G, Deisseroth K. Nat Neurosci 8: 1263-1268, 2005; Deisseroth K. Nat Methods 8: 26-29, 2011). Although these techniques have been most successfully implemented in rodent models, they have the potential to be similarly impactful in studies of nonhuman primate brains. Common marmosets (Callithrix jacchus) have recently emerged as a candidate primate model for gene editing, providing a potentially powerful model for studies of neural circuitry and disease in primates. The application of viral transduction methods in marmosets for identifying and manipulating neuronal circuitry is a crucial step in developing this species for neuroscience research. In the present study we developed a novel, chronic method to successfully induce rapid photostimulation in individual cortical neurons transduced by adeno-associated virus to express channelrhodopsin (ChR2) in awake marmosets. We found that large proportions of neurons could be effectively photoactivated following viral transduction and that this procedure could be repeated for several months. These data suggest that techniques for viral transduction and optical manipulation of neuronal populations are suitable for marmosets and can be combined with existing behavioral preparations in the species to elucidate the functional neural circuitry underlying perceptual and cognitive processes. PMID:27334951

  13. Melanotic ependymoma in a Goeldi's marmoset (Callimico goeldii).

    PubMed

    Nichols, D K; Dias, J L

    1995-01-01

    A spontaneous melanotic ependymoma was observed in the brain of an adult female Goeldi's marmoset (Callimico goeldii). The mass completely occupied the left lateral ventricle, rupturing the fornix and corpus callosum, and compressing the adjacent neuropil. Special histochemical techniques, including melanin bleach, periodic acid-Schiff, Perls iron and phosphotungstic acid hematoxylin, demonstrated the neoplasms to be an ependymoma with a rare melanotic differentiation.

  14. The effect of ondansetron on cognitive performance in the marmoset.

    PubMed

    Domeney, A M; Costall, B; Gerrard, P A; Jones, D N; Naylor, R J; Tyers, M B

    1991-01-01

    The 5-HT3 receptor antagonist, ondansetron, was administered to marmosets to determine its effect on their performance in a Wisconsin General Test Apparatus using an object discrimination reversal learning task. Briefly, this comprised a test situation in which marmosets were required to select a food rewarded object to reach criterion in performance (this was termed the initial discrimination task); the rewarded object was then changed (in the same test session) and the marmoset was required to abandon its recently learned strategy to gain reward by selection of the second object (this was termed the reversal task). At doses of 1-10 ng/kg SC b.i.d. ondansetron improved performance in both the initial discrimination and reversal tasks. This was indicated as a reduction in the number of trials required to reach criterion, a reduction in choice latency time and a reduction in the number of errors made in each test session. Higher doses of ondansetron impaired performance as measured by several criteria. The major conclusion of this study is, therefore, that ondansetron at low doses is able to improve the performance of marmosets in a cognitive task. This would support the concept that a 5-HT3 receptor antagonist can act as a cognitive enhancer.

  15. Strategies in Landmark Use by Children, Adults, and Marmoset Monkeys

    ERIC Educational Resources Information Center

    MacDonald, Suzanne E.; Spetch, Marcia L.; Kelly, Debbie M.; Cheng, Ken

    2004-01-01

    Common marmosets ("Callithrix jacchus jacchus"), human children, and human adults learned to find a goal that was located in the center of a square array of four identical landmarks. The location of the landmark array and corresponding goal varied across trials, so the task could not be solved without using the landmark array. In Experiment 1, a…

  16. Response variability of marmoset parvocellular neurons.

    PubMed

    Victor, J D; Blessing, E M; Forte, J D; Buzás, P; Martin, P R

    2007-02-15

    This study concerns the properties of neurons carrying signals for colour vision in primates. We investigated the variability of responses of individual parvocellular lateral geniculate neurons of dichromatic and trichromatic marmosets to drifting sinusoidal luminance and chromatic gratings. Response variability was quantified by the cycle-to-cycle variation in Fourier components of the response. Averaged across the population, the variability at low contrasts was greater than predicted by a Poisson process, and at high contrasts the responses were approximately 40% more variable than responses at low contrasts. The contrast-dependent increase in variability was nevertheless below that expected from the increase in firing rate. Variability falls below the Poisson prediction at high contrast, and intrinsic variability of the spike train decreases as contrast increases. Thus, while deeply modulated responses in parvocellular cells have a larger absolute variability than weakly modulated ones, they have a more favourable signal: noise ratio than predicted by a Poisson process. Similar results were obtained from a small sample of magnocellular and koniocellular ('blue-on') neurons. For parvocellular neurons with pronounced colour opponency, chromatic responses were, on average, less variable (10-15%, p<0.01) than luminance responses of equal magnitude. Conversely, non-opponent parvocellular neurons showed the opposite tendency. This is consistent with a supra-additive noise source prior to combination of cone signals. In summary, though variability of parvocellular neurons is largely independent of the way in which they combine cone signals, the noise characteristics of retinal circuitry may augment specialization of parvocellular neurons to signal luminance or chromatic contrast. PMID:17124265

  17. Effects of lurasidone on executive function in common marmosets.

    PubMed

    Murai, Takeshi; Nakako, Tomokazu; Ikejiri, Masaru; Ishiyama, Takeo; Taiji, Mutsuo; Ikeda, Kazuhito

    2013-06-01

    Cognitive impairment is one of the major symptoms of schizophrenia, and is considered largely due to dysfunctions in the prefrontal cortex (PFC). Lurasidone, a novel atypical antipsychotic agent with high binding affinity for dopamine D2, serotonin 5-HT7, 5-HT2A and 5-HT1A receptors has been reported to have superior efficacy in rodents' models of cognitive impairment. However, the beneficial effect of lurasidone on cognitive impairment has not been evaluated in non-human primates. In this study, we investigated the effect of lurasidone on executive function, which is one of the cognitive domains, in common marmosets and compared the results to those of other antipsychotics. The effects of lurasidone, haloperidol, olanzapine, risperidone, quetiapine and clozapine on executive function were evaluated in naïve marmosets using the object retrieval with detours (ORD) task. Before drug treatment, marmosets' success rates in the easy trial of the test were almost 90%. However, maximum success in the difficult trial of the task reached only 50% after 8 days of training. Haloperidol, olanzapine and risperidone decreased correct performance even in the easy trial of the task. All drugs, except lurasidone, impaired success rate in the difficult trial. On the other hand, lurasidone dose-dependently increased marmosets' success rates in the difficult trial with significant effect at 10mg/kg. In conclusion, we have shown in this study that lurasidone, unlike conventional antipsychotics, improves cognition associated with executive function in common marmosets. These findings suggest that lurasidone would be more useful for treatment of schizophrenia cognitive impairment than other antipsychotics.

  18. A case of nontraumatic gas gangrene in a common marmoset (Callithrix jacchus)

    PubMed Central

    YASUDA, Masahiko; INOUE, Takashi; UENO, Masami; MORITA, Hanako; HAYASHIMOTO, Nobuhito; KAWAI, Kenji; ITOH, Toshio

    2015-01-01

    The common marmoset is widely used in neuroscience and regenerative medicine research. However, information concerning common marmoset disorders, particularly infectious diseases, is scarce. Here, we report a case of a female common marmoset that died suddenly due to gas gangrene. The animal presented with gaseous abdominal distention at postmortem, and Clostridium perfringens type A was isolated from several tissues. Vacuoles, a Gram-positive bacteremia and intravascular hemolysis were observed microscopically in the muscles, liver and lungs. On the basis of these findings, we diagnosed nontraumatic gas gangrene caused by Clostridium perfringens type A in this common marmoset. PMID:26156080

  19. Diencephalic connections of the superior colliculus in the hedgehog tenrec.

    PubMed

    Künzle, H

    1996-10-01

    Using different tracer substances the pathways connecting the superior colliculus with the diencephalon were studied in the Madagascan hedgehog tenrec (Echinops telfairi), a nocturnal insectivore with tiny eyes, a small and little differentiated superior colliculus and a visual cortex with no obvious fourth granular layer. The most prominent tecto-thalamic projection terminated in the ipsilateral dorsal lateral geniculate nucleus. The entire region receiving contralateral retinal afferents was labeled with variable density. In addition, there was a widespread, homogeneously distributed collicular input to the lateralis posterior-pulvinar complex and a distinct tectal projection to the suprageniculate nucleus. The latter projections were bilateral with a clear ipsilateral predominance. Among the intra- and paralaminar nuclei the centralis lateralis complex was most heavily labeled on both sides, followed by the nucleus centralis medialis. The paralamellar portion of the nucleus medialis dorsalis and the nucleus parafascicularis received sparse projections. A clear projection to the nucleus ventralis medialis could not be demonstrated but its presence was not entirely excluded either. There were also projections to medial thalamic nuclei, particularly the reuniens complex and the nucleus paraventricularis thalami. The main tecto-subthalamic target regions were the zona incerta, the dorsal hypothalamus and distinct subdivisons of the ventral lateral geniculate nucleus. These regions also gave rise to projections to the superior colliculus, as did the intergeniculate leaflet. The pathways oriented toward the visual or frontal cortex and the projections possibly involved in limbic and circadian mechanisms were compared with the connectivity patterns reported in mammals with more differentiated brains. Particular attention was given to the tenrec's prominent tecto-geniculate projection, the presumed W- or K-pathway directed toward the supragranular layers.

  20. Do marmosets care to share? Oxytocin treatment reduces prosocial behavior toward strangers

    PubMed Central

    Mustoe, Aaryn C.; Cavanaugh, Jon; Harnisch, April M.; Thompson, Breanna E.; French, Jeffrey A.

    2015-01-01

    Cooperatively-breeding and socially-monogamous primates, like marmosets and humans, exhibit high levels of social tolerance and prosociality toward others. Oxytocin (OXT) generally facilitates prosocial behavior, but there is growing recognition that OXT modulation of prosocial behavior is shaped by the context of social interactions and by other motivational states such as arousal or anxiety. To determine whether prosociality varies based on social context, we evaluated whether marmoset donors (Callithrix penicillata) preferentially rewarded pairmates versus opposite-sex strangers in a prosocial food-sharing task. To examine potential links among OXT, stress systems, and prosociality, we evaluated whether pretrial cortisol levels in marmosets altered the impact of OXT on prosocial responses. Marmosets exhibited spontaneous prosociality toward others, but they did so preferentially toward strangers compared to their pairmates. When donor marmosets were treated with marmoset-specific Pro8-OXT, they exhibited reduced prosociality toward strangers compared to marmosets treated with saline or consensus-mammalian Leu8-OXT. When pretrial cortisol levels were lower, marmosets exhibited higher prosociality toward strangers. These findings demonstrate that while marmosets show spontaneous prosocial responses toward others, they do so preferentially toward opposite-sex strangers. Cooperative breeding may be associated with the expression of prosociality, but the existence of a pair-bond between marmoset partners appears to be neither necessary nor sufficient for the expression of spontaneous prosocial responses. Further, high prosociality toward strangers is significantly reduced in marmosets treated with Pro8-OXT, suggesting that OXT does not universally enhance prosociality, but, rather OXT modulation of prosocial behavior varies depending on social context. PMID:25934057

  1. SMI-32 parcellates the visual cortical areas of the marmoset.

    PubMed

    Baldauf, Zsolt B

    The distribution pattern of SMI-32-immunoreactivity (SMI-32-ir) of neuronal elements was examined in the visual cortical areas of marmoset monkey. Layer IV of the primary visual cortex (V1) and layers III and V of the extrastriate areas showed the most abundant SMI-32-ir. The different areal and laminar distribution of SMI-32-ir allowed the distinction between various extrastriate areas and determined their exact anatomical boundaries in the New World monkey, Callithrix penicillata. It is shown here that the parcellating nature of SMI-32 described earlier in the visual cortical areas of other mammals - including Old World monkeys - is also present in the marmoset. Furthermore, a comparison became possible between the chemoanatomical organization of New World and Old World primates' visual cortical areas.

  2. LANGUAGE DEVELOPMENT. The developmental dynamics of marmoset monkey vocal production.

    PubMed

    Takahashi, D Y; Fenley, A R; Teramoto, Y; Narayanan, D Z; Borjon, J I; Holmes, P; Ghazanfar, A A

    2015-08-14

    Human vocal development occurs through two parallel interactive processes that transform infant cries into more mature vocalizations, such as cooing sounds and babbling. First, natural categories of sounds change as the vocal apparatus matures. Second, parental vocal feedback sensitizes infants to certain features of those sounds, and the sounds are modified accordingly. Paradoxically, our closest living ancestors, nonhuman primates, are thought to undergo few or no production-related acoustic changes during development, and any such changes are thought to be impervious to social feedback. Using early and dense sampling, quantitative tracking of acoustic changes, and biomechanical modeling, we showed that vocalizations in infant marmoset monkeys undergo dramatic changes that cannot be solely attributed to simple consequences of growth. Using parental interaction experiments, we found that contingent parental feedback influences the rate of vocal development. These findings overturn decades-old ideas about primate vocalizations and show that marmoset monkeys are a compelling model system for early vocal development in humans. PMID:26273055

  3. Motion dependence of smooth pursuit eye movements in the marmoset

    PubMed Central

    Priebe, Nicholas J.; Miller, Cory T.

    2015-01-01

    Smooth pursuit eye movements stabilize slow-moving objects on the retina by matching eye velocity with target velocity. Two critical components are required to generate smooth pursuit: first, because it is a voluntary eye movement, the subject must select a target to pursue to engage the tracking system; and second, generating smooth pursuit requires a moving stimulus. We examined whether this behavior also exists in the common marmoset, a New World primate that is increasingly attracting attention as a genetic model for mental disease and systems neuroscience. We measured smooth pursuit in two marmosets, previously trained to perform fixation tasks, using the standard Rashbass step-ramp pursuit paradigm. We first measured the aspects of visual motion that drive pursuit eye movements. Smooth eye movements were in the same direction as target motion, indicating that pursuit was driven by target movement rather than by displacement. Both the open-loop acceleration and closed-loop eye velocity exhibited a linear relationship with target velocity for slow-moving targets, but this relationship declined for higher speeds. We next examined whether marmoset pursuit eye movements depend on an active engagement of the pursuit system by measuring smooth eye movements evoked by small perturbations of motion from fixation or during pursuit. Pursuit eye movements were much larger during pursuit than from fixation, indicating that pursuit is actively gated. Several practical advantages of the marmoset brain, including the accessibility of the middle temporal (MT) area and frontal eye fields at the cortical surface, merit its utilization for studying pursuit movements. PMID:25867740

  4. Use of the common marmoset to study Burkholderia mallei infection.

    PubMed

    Jelesijevic, Tomislav; Zimmerman, Shawn M; Harvey, Stephen B; Mead, Daniel G; Shaffer, Teresa L; Estes, D Mark; Michel, Frank; Quinn, Frederick D; Hogan, Robert J; Lafontaine, Eric R

    2015-01-01

    Burkholderia mallei is a host-adapted bacterium that does not persist outside of its equine reservoir. The organism causes the zoonosis glanders, which is endemic in Asia, Africa, the Middle East and South America. Infection by B. mallei typically occurs via the respiratory or percutaneous route, and the most common manifestations are life-threatening pneumonia and bacteremia. Glanders is difficult to diagnose and requires prolonged antibiotic therapy with low success rates. There is no vaccine to protect against B. mallei and there is concern regarding its use as a biothreat agent. Thus, experiments were performed to establish a non-human primate model of intranasal infection to study the organism and develop countermeasures. Groups of marmosets (Callithrix jacchus) were inoculated intranasally with B. mallei strain ATCC 23344 and monitored for clinical signs of illness for up to 13 days. We discovered that 83% of marmosets inoculated with doses of 2.5 X 10(4) to 2.5 X 10(5) bacteria developed acute lethal infection within 3-4 days. Signs of disease were severe and included lethargy, inappetence, conjunctivitis, mucopurulent and hemorrhagic nasal discharges, and increased respiratory effort with abdominal lifts. Burkholderia mallei was cultured from the lungs, spleen and liver of these animals, and pathologic examination of tissues revealed lesions characteristic of glanders. Challenge experiments also revealed that 91% of animals infected with doses ranging from 25 to 2.5 X 10(3) bacteria exhibited mild non-specific signs of illness and were culture negative. One marmoset inoculated with 2.5 X 10(3) organisms developed moderate signs of disease and reached humane end-points 8 days post-infection. The liver and spleen of this animal were colonized with the agent and pathological analysis of tissues showed nasal, splenic and hepatic lesions. Taken together, these data indicate that the marmoset is a suitable model to study respiratory infection by B. mallei.

  5. Use of the Common Marmoset to Study Burkholderia mallei Infection

    PubMed Central

    Harvey, Stephen B.; Mead, Daniel G.; Shaffer, Teresa L.; Estes, D. Mark; Michel, Frank; Quinn, Frederick D.; Hogan, Robert J.; Lafontaine, Eric R.

    2015-01-01

    Burkholderia mallei is a host-adapted bacterium that does not persist outside of its equine reservoir. The organism causes the zoonosis glanders, which is endemic in Asia, Africa, the Middle East and South America. Infection by B. mallei typically occurs via the respiratory or percutaneous route, and the most common manifestations are life-threatening pneumonia and bacteremia. Glanders is difficult to diagnose and requires prolonged antibiotic therapy with low success rates. There is no vaccine to protect against B. mallei and there is concern regarding its use as a biothreat agent. Thus, experiments were performed to establish a non-human primate model of intranasal infection to study the organism and develop countermeasures. Groups of marmosets (Callithrix jacchus) were inoculated intranasally with B. mallei strain ATCC 23344 and monitored for clinical signs of illness for up to 13 days. We discovered that 83% of marmosets inoculated with doses of 2.5 X 104 to 2.5 X 105 bacteria developed acute lethal infection within 3–4 days. Signs of disease were severe and included lethargy, inappetence, conjunctivitis, mucopurulent and hemorrhagic nasal discharges, and increased respiratory effort with abdominal lifts. Burkholderia mallei was cultured from the lungs, spleen and liver of these animals, and pathologic examination of tissues revealed lesions characteristic of glanders. Challenge experiments also revealed that 91% of animals infected with doses ranging from 25 to 2.5 X 103 bacteria exhibited mild non-specific signs of illness and were culture negative. One marmoset inoculated with 2.5 X 103 organisms developed moderate signs of disease and reached humane end-points 8 days post-infection. The liver and spleen of this animal were colonized with the agent and pathological analysis of tissues showed nasal, splenic and hepatic lesions. Taken together, these data indicate that the marmoset is a suitable model to study respiratory infection by B. mallei. PMID

  6. Modulation of physical understanding by common marmosets (Callithrix jacchus).

    PubMed

    Yamazaki, Yumiko; Iriki, Atsushi; Watanabe, Shigeru

    2011-03-01

    The understanding of physical causality in common marmosets was tested using support problems in which a pair of sheets was presented to determine whether subjects would choose the sheet that had a food item on it (i.e., the sheet was supporting the food item). In two experiments, the conditions were manipulated in terms of the length of the sheet, the distance between the sheet and the food item, the presence of a gap separating the two sheets, and the size of the food item. In Experiment 1, the marmosets had difficulty rejecting an irretrievable food item when it was located closer to them than a retrievable item. Although their performance was strongly affected by the size of the irretrievable food item, they quickly learned to reject that alternative. In contrast, no improvement was found when one sheet was divided into two pieces such that the food item could not be retrieved when its near side was pulled. A similar response tendency was observed in Experiment 2, in which the effects of the large food item were examined in three different conditions. Thus, common marmosets were influenced by the perceptual features of the food in solving the support problems, as are other non-human primates. In addition, they consistently failed to appreciate the presence of a gap and, therefore, failed to reject the distracter alternative. However, all animals rapidly learned that the size of the food item was an irrelevant variable, and some showed an elementary conceptual understanding of support. These findings suggest that marmosets' physical understanding may improve with experience.

  7. Cooperative vocal control in marmoset monkeys via vocal feedback

    PubMed Central

    Choi, Jung Yoon; Takahashi, Daniel Y.

    2015-01-01

    Humans adjust speech amplitude as a function of distance from a listener; we do so in a manner that would compensate for such distance. This ability is presumed to be the product of high-level sociocognitive skills. Nonhuman primates are thought to lack such socially related flexibility in vocal production. Using predictions from a simple arousal-based model whereby vocal feedback from a conspecific modulates the drive to produce a vocalization, we tested whether another primate exhibits this type of cooperative vocal control. We conducted a playback experiment with marmoset monkeys and simulated “far-away” and “nearby” conspecifics using contact calls that differed in sound intensity. We found that marmoset monkeys increased the amplitude of their contact calls and produced such calls with shorter response latencies toward more distant conspecifics. The same was not true in response to changing levels of background noise. To account for how simulated conspecific distance can change both the amplitude and timing of vocal responses, we developed a model that incorporates dynamic interactions between the auditory system and limbic “drive” systems. Overall, our data show that, like humans, marmoset monkeys cooperatively control the acoustics of their vocalizations according to changes in listener distance, increasing the likelihood that a conspecific will hear their call. However, we propose that such cooperative vocal control is a system property that does not necessitate any particularly advanced sociocognitive skill. At least in marmosets, this vocal control can be parsimoniously explained by the regulation of arousal states across two interacting individuals via vocal feedback. PMID:25925323

  8. Metabolic Characterization of the Common Marmoset (Callithrix jacchus)

    PubMed Central

    Go, Young-Mi; Liang, Yongliang; Uppal, Karan; Soltow, Quinlyn A.; Promislow, Daniel E. L.; Wachtman, Lynn M.; Jones, Dean P.

    2015-01-01

    High-resolution metabolomics has created opportunity to integrate nutrition and metabolism into genetic studies to improve understanding of the diverse radiation of primate species. At present, however, there is very little information to help guide experimental design for study of wild populations. In a previous non-targeted metabolomics study of common marmosets (Callithrix jacchus), Rhesus macaques, humans, and four non-primate mammalian species, we found that essential amino acids (AA) and other central metabolites had interspecies variation similar to intraspecies variation while non-essential AA, environmental chemicals and catabolic waste products had greater interspecies variation. The present study was designed to test whether 55 plasma metabolites, including both nutritionally essential and non-essential metabolites and catabolic products, differ in concentration in common marmosets and humans. Significant differences were present for more than half of the metabolites analyzed and included AA, vitamins and central lipid metabolites, as well as for catabolic products of AA, nucleotides, energy metabolism and heme. Three environmental chemicals were present at low nanomolar concentrations but did not differ between species. Sex and age differences in marmosets were present for AA and nucleotide metabolism and warrant additional study. Overall, the results suggest that quantitative, targeted metabolomics can provide a useful complement to non-targeted metabolomics for studies of diet and environment interactions in primate evolution. PMID:26581102

  9. Generation of transgenic marmosets expressing genetically encoded calcium indicators

    PubMed Central

    Park, Jung Eun; Zhang, Xian Feng; Choi, Sang-Ho; Okahara, Junko; Sasaki, Erika; Silva, Afonso C.

    2016-01-01

    Chronic monitoring of neuronal activity in the living brain with optical imaging techniques became feasible owing to the continued development of genetically encoded calcium indicators (GECIs). Here we report for the first time the successful generation of transgenic marmosets (Callithrix jacchus), an important nonhuman primate model in neurophysiological research, which were engineered to express the green fluorescent protein (GFP)-based family of GECIs, GCaMP, under control of either the CMV or the hSyn promoter. High titer lentiviral vectors were produced, and injected into embryos collected from donor females. The infected embryos were then transferred to recipient females. Eight transgenic animals were born and shown to have stable and functional GCaMP expression in several different tissues. Germline transmission of the transgene was confirmed in embryos generated from two of the founder transgenic marmosets that reached sexual maturity. These embryos were implanted into six recipient females, three of which became pregnant and are in advanced stages of gestation. We believe these transgenic marmosets will be invaluable non-human primate models in neuroscience, allowing chronic in vivo monitoring of neural activity with functional confocal and multi-photon optical microscopy imaging of intracellular calcium dynamics. PMID:27725685

  10. Functional Connectivity Hubs and Networks in the Awake Marmoset Brain

    PubMed Central

    Belcher, Annabelle M.; Yen, Cecil Chern-Chyi; Notardonato, Lucia; Ross, Thomas J.; Volkow, Nora D.; Yang, Yihong; Stein, Elliot A.; Silva, Afonso C.; Tomasi, Dardo

    2016-01-01

    In combination with advances in analytical methods, resting-state fMRI is allowing unprecedented access to a better understanding of the network organization of the brain. Increasing evidence suggests that this architecture may incorporate highly functionally connected nodes, or “hubs”, and we have recently proposed local functional connectivity density (lFCD) mapping to identify highly-connected nodes in the human brain. Here, we imaged awake nonhuman primates to test whether, like the human brain, the marmoset brain contains FC hubs. Ten adult common marmosets (Callithrix jacchus) were acclimated to mild, comfortable restraint using individualized helmets. Following restraint training, resting BOLD data were acquired during eight consecutive 10 min scans for each subject. lFCD revealed prominent cortical and subcortical hubs of connectivity across the marmoset brain; specifically, in primary and secondary visual cortices (V1/V2), higher-order visual association areas (A19M/V6[DM]), posterior parietal and posterior cingulate areas (PGM and A23b/A31), thalamus, dorsal and ventral striatal areas (caudate, putamen, lateral septal nucleus, and anterior cingulate cortex (A24a). lFCD hubs were highly connected to widespread areas of the brain, and further revealed significant network-network interactions. These data provide a baseline platform for future investigations in a nonhuman primate model of the brain’s network topology. PMID:26973476

  11. T-and B-lymphocyte chimerism in the marmoset.

    PubMed Central

    Niblack, G D; Kateley, J R; Gengozian, N

    1977-01-01

    Marmosets are natural blood chimeras, this condition resulting from the high frequency of fraternal twinning and the consistent development of placental vasular anastomoses between the two embryos. Identification of chimerism by sex-chromosome analysis of cultured blood lymphocytes provided a means of determining the proportion of chimerism among T and B lymphocytes. Peripheral blood lymphocytes were enriched for T or B cells by filtration through a nylon column (yields greater than 95 per cent T-cells) or inactivation of T lymphocytes by treatment with a goat anti-marmoset thymocyte antiserum in the presence of complement (yeilds greater than 95 per cent B cells). Mitogenic stimulation of these separated, enriched cell populations yielded metaphase plates which could be scored for percentage male and female cells. Tests on five different blood chimeras showed the T- and B-lymphocyte chimerism to be the same. Stimulation of blood lymphocytes with cells from another species of marmoset in a mixed lymphocyte culture test revealed the chimeric T-cell response (i.e., host and co-twin cells) to be similar to that obtained with a mitogenic lectin. The demonstration of equivalent T- and B-cell chimerism in these animals suggests derivation of these cells from a common stem cell pool and the response of both T-cell populations to an antigenic stimulus in proportions similar to their percentage chimerism suggests complete immunologic tolerance exists in this species for co-twin histocompatibility antigens. PMID:139360

  12. Individual variability in visual discrimination and reversal learning performance in common marmosets.

    PubMed

    Takemoto, Atsushi; Miwa, Miki; Koba, Reiko; Yamaguchi, Chieko; Suzuki, Hiromi; Nakamura, Katsuki

    2015-04-01

    Detailed information about the characteristics of learning behavior in marmosets is useful for future marmoset research. We trained 42 marmosets in visual discrimination and reversal learning. All marmosets could learn visual discrimination, and all but one could complete reversal learning, though some marmosets failed to touch the visual stimuli and were screened out. In 87% of measurements, the final percentage of correct responses was over 95%. We quantified performance with two measures: onset trial and dynamic interval. Onset trial represents the number of trials that elapsed before the marmoset started to learn. Dynamic interval represents the number of trials from the start before reaching the final percentage of correct responses. Both measures decreased drastically as a result of the formation of discrimination learning sets. In reversal learning, both measures worsened, but the effect on onset trial was far greater. The effects of age and sex were not significant as far as we used adolescent or young adult marmosets. Unexpectedly, experimental circumstance (in the colony or isolator) had only a subtle effect on performance. However, we found that marmosets from different families exhibited different learning process characteristics, suggesting some family effect on learning.

  13. Decision making and risk attitude of the common marmoset in a gambling task.

    PubMed

    Tokuno, Hironobu; Tanaka, Ikuko

    2011-11-01

    To analyze decision making under uncertainty of monkeys, common marmosets were trained to choose and remove one of two colored caps on wells arranged side by side. Each well contained constant reward (3 grains of puffed rice) or risky reward (0 or 6 grains; probability, 50%:50%). For each marmoset, white or black color was assigned randomly as a symbol of non-risky or risky choice. Arrangement of white and black caps was determined randomly in each trial. After 200 trials (5 trials per day), the marmosets were classified according to the pattern of their choice. Eight of 18 marmosets (44.4%) were risk-aversive, whereas 5 marmosets (27.8%) were risk-prone. The remaining 5 marmosets (27.8%) preferred to choose one side (left n=4, right n=1). These results showed individual differences in decision making of marmosets. An additional task with reduction in the expected value of the preferred choice revealed that risk-aversive marmosets were slower to adjust their choices to such reductions than risk-prone animals.

  14. Inferior alveolar nerve repositioning.

    PubMed

    Louis, P J

    2001-09-01

    Nerve repositioning is a viable alternative for patients with an atrophic edentulous posterior mandible. Patients, however, should be informed of the potential risks of neurosensory disturbance. Documentation of the patient's baseline neurosensory function should be performed with a two-point discrimination test or directional brush stroke test preoperatively and postoperatively. Recovery of nerve function should be expected in 3 to 6 months. The potential for mandibular fracture when combining nerve repositioning with implant placement also should be discussed with the patient. This can be avoided by minimizing the amount of buccal cortical plate removal during localization of the nerve and maintaining the integrity of the inferior cortex of the mandible. Additionally, avoid overseating the implant, thus avoiding stress along the inferior border of the mandible. The procedure does allow for the placement of longer implants, which should improve implant longevity. Patients undergoing this procedure have expressed overall satisfaction with the results. Nerve repositioning also can be used to preserve the inferior alveolar nerve during resection of benign tumors or cysts of the mandible. This procedure allows the surgeon to maintain nerve function in situations in which the nerve would otherwise have to be resected. PMID:11665379

  15. Incarcerated inferior lumbar (Petit's) hernia.

    PubMed

    Astarcioğlu, H; Sökmen, S; Atila, K; Karademir, S

    2003-09-01

    Petit's hernia is an uncommon abdominal wall defect in the inferior lumbar triangle. Colonic incarceration through the inferior lumbar triangle, which causes mechanical obstructive symptoms, necessitates particular diagnostic and management strategy. We present a rare case of inferior lumbar hernia, leading to mechanical bowel obstruction, successfully treated with prosthetic mesh reinforcement repair.

  16. Control of the superior colliculus by the lateral prefrontal cortex

    PubMed Central

    Everling, Stefan; Johnston, Kevin

    2013-01-01

    Several decades of patient, functional imaging and neurophysiological studies have supported a model in which the lateral prefrontal cortex (PFC) acts to suppress unwanted saccades by inhibiting activity in the oculomotor system. However, recent results from combined PFC deactivation and neural recordings of the superior colliculus in monkeys demonstrate that the primary influence of the PFC on the oculomotor system is excitatory, and stands in direct contradiction to the inhibitory model of PFC function. Although erroneous saccades towards a visual stimulus are commonly labelled reflexive in patients with PFC damage or dysfunction, the latencies of most of these saccades are outside of the range of express saccades, which are triggered directly by the visual stimulus. Deactivation and pharmacological manipulation studies in monkeys suggest that response errors following PFC damage or dysfunction are not the result of a failure in response suppression but can best be understood in the context of a failure to maintain and implement the proper task set. PMID:24018729

  17. Deficits in saccade target selection after inactivation of superior colliculus.

    PubMed

    McPeek, Robert M; Keller, Edward L

    2004-07-01

    Saccades are rapid eye movements that orient gaze toward areas of interest in the visual scene. Neural activity correlated with saccade target selection has been identified in several brain regions, including the superior colliculus (SC), but it is not known whether the SC is directly involved in target selection, or whether the SC merely receives selection-related signals from cortex in preparation for the execution of eye movements. In monkeys, we used focal reversible inactivation to test the functional contributions of the SC to target selection during visual search, and found that inactivation resulted in clear deficits. When a target appeared in the inactivated field, saccades were often misdirected to distractor stimuli. Control tasks showed that this deficit was not caused by low-level visual or motor impairments. Our results indicate that, in addition to its well-established involvement in movement execution, the SC has an important functional role in target selection. PMID:15195099

  18. Isolated inferior mesenteric portal hypertension with giant inferior mesenteric vein and anomalous inferior mesenteric vein insertion

    PubMed Central

    Prasad, G. Raghavendra; Billa, Srikar; Bhandari, Pavaneel; Hussain, Aijaz

    2013-01-01

    Extrahepatic portal hypertension is not an uncommon disease in childhood, but isolated inferior mesenteric portal varices and lower gastrointestinal (GI) bleed have not been reported till date. A 4-year-old girl presented with lower GI bleed. Surgical exploration revealed extrahepatic portal vein obstruction with giant inferior mesenteric vein and colonic varices. Inferior mesenteric vein was joining the superior mesenteric vein. The child was treated successfully with inferior mesenteric – inferior vena caval anastomosis. The child was relieved of GI bleed during the follow-up. PMID:23798814

  19. Age-related audiovisual interactions in the superior colliculus of the rat.

    PubMed

    Costa, M; Piché, M; Lepore, F; Guillemot, J-P

    2016-04-21

    It is well established that multisensory integration is a functional characteristic of the superior colliculus that disambiguates external stimuli and therefore reduces the reaction times toward simple audiovisual targets in space. However, in a condition where a complex audiovisual stimulus is used, such as the optical flow in the presence of modulated audio signals, little is known about the processing of the multisensory integration in the superior colliculus. Furthermore, since visual and auditory deficits constitute hallmark signs during aging, we sought to gain some insight on whether audiovisual processes in the superior colliculus are altered with age. Extracellular single-unit recordings were conducted in the superior colliculus of anesthetized Sprague-Dawley adult (10-12 months) and aged (21-22 months) rats. Looming circular concentric sinusoidal (CCS) gratings were presented alone and in the presence of sinusoidally amplitude modulated white noise. In both groups of rats, two different audiovisual response interactions were encountered in the spatial domain: superadditive, and suppressive. In contrast, additive audiovisual interactions were found only in adult rats. Hence, superior colliculus audiovisual interactions were more numerous in adult rats (38%) than in aged rats (8%). These results suggest that intersensory interactions in the superior colliculus play an essential role in space processing toward audiovisual moving objects during self-motion. Moreover, aging has a deleterious effect on complex audiovisual interactions.

  20. A modified light-dark box test for the common marmoset.

    PubMed

    Wang, Yiwen; Fang, Qin; Gong, Neng

    2014-06-01

    The common marmoset (Callithrix jacchus) has attracted extensive attention for use as a non-human primate model in biomedical research, especially in the study of neuropsychiatric disorders. However, behavioral test methods are still limited in the field of marmoset research. The light-dark box is widely used for the evaluation of anxiety in rodents, but little is known about light-dark preference in marmosets. Here, we modified the light-dark test to study this behavior. The modified apparatus consisted of three compartments: one transparent open area and two closed opaque compartments. The closed compartments could be dark or light. We found that both adult and young marmosets liked to explore the open area, but the young animals showed more interest than adults. Furthermore, when one of the closed compartments was light and the other dark, the adult marmosets showed a preference for the dark compartment, but the young animals had no preference. These results suggest that the exploratory behavior and the light-dark preference in marmosets are age-dependent. Our study provides a new method to study exploration, anxiety, and fear in marmosets.

  1. Anemia, myopathy, and pansteatitis in vitamin E-deficient captive marmosets (Callithrix spp.).

    PubMed

    Juan-Sallés, C; Prats, N; Resendes, A; Domingo, M; Hilton, D; Ruiz, J M; Garner, M M; Valls, X; Marco, A J

    2003-09-01

    Five young adult pet marmosets (Callithrix spp.) were presented with weight loss (5/5); fecal retention (3/5); diarrhea (2/5); impaired locomotion (3/5); anemia (4/4); hypoproteinemia or hypoalbuminemia (3/4); elevations of creatine phosphokinase, lactic dehydrogenase, and alanine aminotransferase (3/4); and renal failure with hypercholesterolemia (2/4). All anemic marmosets had low serum vitamin E levels. The anemia responded to vitamin E and selenium therapy in two marmosets. One of the five marmosets died before presentation, and two others died despite therapy. The two marmosets necropsied had degenerative myopathy, pyogranulomatous pansteatitis, and increased erythrophagocytosis and hemosiderosis. The striated muscle and adipose tissue of both marmosets were negative for coxsackievirus ribonucleic acid by in situ hybridization. These findings suggest that vitamin E deficiency may be involved in the development of anemia, myopathy, and steatitis in callitrichids; however, in some marmosets, underlying diseases such as chronic colitis may have influenced the development of anemia and impaired vitamin E status.

  2. Naturally occurring and experimentally induced beta-amyloid deposits in the brains of marmosets (Callithrix jacchus).

    PubMed

    Maclean, C J; Baker, H F; Ridley, R M; Mori, H

    2000-01-01

    Cerebral beta-amyloid occurs in elderly animals of some species and in Alzheimer's disease. Previously, we injected 3 young marmosets intracerebrally with brain tissue from a patient with Alzheimer's disease. Six years later, when the monkeys were middle aged, we found moderate numbers of intracerebral plaques and cerebrovascular deposits containing beta-amyloid. We have re-examined these brains and those of 10 other marmosets injected with brain homogenate containing beta-amyloid, and have found some beta-amyloid in animals injected more than 4 years previously. We have found beta-amyloid in 4 of 26 elderly control marmosets, but not in 9 young to middle-aged control marmosets. The beta-amyloid found in middle aged marmosets injected with Alzheimer brain tissue was, therefore, not a consequence of their age. Deposits in large cerebral vessels in elderly marmosets, and in marmosets previously injected with brain tissue containing beta-amyloid, reacted with antibodies to Abeta and Abeta1-40; plaques and microvessel deposits reacted with antibodies to Abeta and Abeta1-42.

  3. Oestradiol modulation of cognition in adult female marmosets (Callithrix jacchus).

    PubMed

    Lacreuse, A; Chang, J; Metevier, C M; LaClair, M; Meyer, J S; Ferris, C M

    2014-05-01

    The common marmoset (Callithrix jacchus) provides many advantages over traditional rodent and macaque species as a model for human ageing and may be very useful for studying the effects of sex steroids on cognitive and brain ageing. We present the first study examining the effects of oestrogens on cognitive function in female marmosets. Adult monkeys (3-5 years of age) were trained to a specific learning criterion on a battery of cognitive tasks preoperatively (object discrimination, delayed response with increasing delays and detour reaching with opaque box) and were tested on different versions of these tasks (object reversals, delayed response with randomised delays and detour reaching with clear box) after ovariectomy and simultaneous implantation with 17β-oestradiol (E2 ) (n = 6) or blank (n = 6) Silastic capsules. Acquisition of a delayed matching-to-position task with a 1-s delay was also administered after completion of these tests. E2 -treated monkeys were significantly impaired on the second reversal and showed an increase in perseverative responding from reversals 1-3. Their performance also tended to be worse than that of control monkeys on the delayed response task. Performance acquisition on the delayed matching-to-position tended to be better in E2 -treated relative to control monkeys, although the group difference did not reach statistical significance. No effect of treatment was detected for detour reaching or affiliative behaviours. Overall, the findings indicate that E2 compromises performance on prefrontally-mediated tasks. The suggestion that E2 may improve acquisition on tasks dependent on the hippocampus will require further validation. These results are discussed in the context of dopaminergic and serotonergic signalling. We conclude that the marmoset is a useful new primate model for examining the effects of oestrogens on cognitive function.

  4. Dexrazoxane Abrogates Acute Doxorubicin Toxicity in Marmoset Ovary1

    PubMed Central

    Salih, Sana M.; Ringelstetter, Ashley K.; Elsarrag, Mazin Z.; Abbott, David H.; Roti, Elon C. Roti

    2015-01-01

    ABSTRACT Preservation of ovarian function following chemotherapy for nonovarian cancers is a formidable challenge. For prepubescent girls, the only option to prevent chemotherapy damage to the ovary is ovarian tissue cryopreservation, an experimental procedure requiring invasive surgeries to harvest and reimplant tissue, which carries the risk of cancer reintroduction. Drugs that block the primary mechanism of chemotherapy insult, such as dexrazoxane (Dexra) in the context of anthracycline chemotherapy, provide a novel approach for ovarian protection and have the potential to overcome current limitations to oncofertility treatment. Dexra is a catalytic topoisomerase 2 inhibitor that protects the mouse ovary from acute doxorubicin (DXR) chemotherapy toxicity in vitro by preventing DXR-induced DNA damage and subsequent gammaH2AX activation. To translate acute DXR ovarian insult and Dexra protection from mouse to nonhuman primate, freshly obtained marmoset ovarian tissue was cultured in vitro and treated with vehicle or 20 μM Dexra 1 h prior to 50 nM DXR. Cultured ovarian tissue was harvested at 2, 4, or 24 h post-DXR treatment. Dexra prevented DXR-induced DNA double-strand breaks as quantified by the neutral comet assay. DXR treatment for 24 h increased gammaH2AX phosphorylation, specifically increasing the number of foci-positive granulosa cells in antral follicles, while Dexra pretreatment inhibited DXR-induced gammaH2AX phosphorylation foci formation. Additionally, Dexra pretreatment trended toward attenuating DXR-induced AKT1 phosphorylation and caspase-9 activation as assayed by Western blots of ovarian tissue lysates. The combined findings suggest Dexra prevents primary DXR-induced DNA damage, the subsequent cellular response to DNA damage, and may diminish early apoptotic signaling in marmoset ovarian tissue. This study provides initial translation of Dexra protection against acute ovarian DXR toxicity from mice to marmoset monkey tissue. PMID:25609833

  5. Oestradiol modulation of cognition in adult female marmosets (Callithrix jacchus)

    PubMed Central

    Lacreuse, Agnès; Chang, Jeemin; Metevier, Christina M.; LaClair, Matthew; Meyer, Jerrold S.; Ferris, Craig M.

    2014-01-01

    The common marmoset (Callithrix jacchus) provides many advantages over traditional rodent and macaque species as a model for human aging and may be very valuable to study the effects of sex steroids on cognitive and brain aging. We present the first study examining the effects of oestrogens on cognitive function in female marmosets. Adult monkeys (3-5 years of age) were trained to a specific learning criterion on a battery of cognitive tasks preoperatively (object discrimination, delayed response with increasing delays and detour reaching with opaque box) and tested on different versions of these tasks (object reversals, delayed response with randomised delays and detour reaching with clear box) following ovariectomy and simultaneous implantation with 17β-oestradiol (E2, n=6) or blank (n=6) Silastic capsules. Acquisition of a delayed matching-to-position task with a 1s delay was also administered following completion of these tests. E2-treated monkeys were significantly impaired on the second Reversal and showed an increase in perseverative responding from Reversals 1 to 3. Their performance also tended to be worse than that of control monkeys on the Delayed Response task. Performance acquisition on the DMP tended to be better in E2-treated relative to control monkeys, but the group difference did not reach statistical significance. No effect of treatment was detected for Detour Reaching or affiliative behaviours. Overall, the findings indicate that E2 compromises performance on prefrontally-mediated tasks. The suggestion that E2 may improve acquisition on tasks dependent on the hippocampus will require further validation. These results are discussed in the context of dopaminergic and serotonergic signaling. We conclude that the marmoset is a useful new primate model to examine the effects of oestrogens on cognitive function. PMID:24617856

  6. A New Marmoset P450 4F12 Enzyme Expressed in Small Intestines and Livers Efficiently Metabolizes Antihistaminic Drug Ebastine.

    PubMed

    Uehara, Shotaro; Uno, Yasuhiro; Yuki, Yukako; Inoue, Takashi; Sasaki, Erika; Yamazaki, Hiroshi

    2016-06-01

    Common marmosets (Callithrix jacchus) are attracting attention as animal models in preclinical studies for drug development. However, cytochrome P450s (P450s), major drug-metabolizing enzymes, have not been fully identified and characterized in marmosets. In this study, based on the four novel P450 4F genes found on the marmoset genome, we successfully isolated P450 4F2, 4F3B, 4F11, and 4F12 cDNAs in marmoset livers. Deduced amino acid sequences of the four marmoset P450 4F forms exhibited high sequence identities (87%-93%) to the human and cynomolgus monkey P450 4F homologs. Marmoset P450 4F3B and 4F11 mRNAs were predominantly expressed in livers, whereas marmoset P450 4F2 and 4F12 mRNAs were highly expressed in small intestines and livers. Four marmoset P450 4F proteins heterologously expressed in Escherichia coli catalyzed the ω-hydroxylation of leukotriene B4 In addition, marmoset P450 4F12 effectively catalyzed the hydroxylation of antiallergy drug ebastine, a human P450 2J/4F probe substrate. Ebastine hydroxylation activities by small intestine and liver microsomes from marmosets and cynomolgus monkeys showed greatly higher values than those of humans. Ebastine hydroxylation activities by marmoset and cynomolgus monkey small intestine microsomes were inhibited (approximately 60%) by anti-P450 4F antibodies, unlike human small intestine microsomes, suggesting that contribution of P450 4F enzymes for ebastine hydroxylation in the small intestine might be different between marmosets/cynomolgus monkeys and humans. These results indicated that marmoset P450 4F2, 4F3B, 4F11, and 4F12 were expressed in livers and/or small intestines and were functional in the metabolism of endogenous and exogenous compounds, similar to those of cynomolgus monkeys and humans.

  7. A New Marmoset P450 4F12 Enzyme Expressed in Small Intestines and Livers Efficiently Metabolizes Antihistaminic Drug Ebastine.

    PubMed

    Uehara, Shotaro; Uno, Yasuhiro; Yuki, Yukako; Inoue, Takashi; Sasaki, Erika; Yamazaki, Hiroshi

    2016-06-01

    Common marmosets (Callithrix jacchus) are attracting attention as animal models in preclinical studies for drug development. However, cytochrome P450s (P450s), major drug-metabolizing enzymes, have not been fully identified and characterized in marmosets. In this study, based on the four novel P450 4F genes found on the marmoset genome, we successfully isolated P450 4F2, 4F3B, 4F11, and 4F12 cDNAs in marmoset livers. Deduced amino acid sequences of the four marmoset P450 4F forms exhibited high sequence identities (87%-93%) to the human and cynomolgus monkey P450 4F homologs. Marmoset P450 4F3B and 4F11 mRNAs were predominantly expressed in livers, whereas marmoset P450 4F2 and 4F12 mRNAs were highly expressed in small intestines and livers. Four marmoset P450 4F proteins heterologously expressed in Escherichia coli catalyzed the ω-hydroxylation of leukotriene B4 In addition, marmoset P450 4F12 effectively catalyzed the hydroxylation of antiallergy drug ebastine, a human P450 2J/4F probe substrate. Ebastine hydroxylation activities by small intestine and liver microsomes from marmosets and cynomolgus monkeys showed greatly higher values than those of humans. Ebastine hydroxylation activities by marmoset and cynomolgus monkey small intestine microsomes were inhibited (approximately 60%) by anti-P450 4F antibodies, unlike human small intestine microsomes, suggesting that contribution of P450 4F enzymes for ebastine hydroxylation in the small intestine might be different between marmosets/cynomolgus monkeys and humans. These results indicated that marmoset P450 4F2, 4F3B, 4F11, and 4F12 were expressed in livers and/or small intestines and were functional in the metabolism of endogenous and exogenous compounds, similar to those of cynomolgus monkeys and humans. PMID:27044800

  8. Neuronal relationships between the dorsal periaqueductal nucleus and the inferior colliculus (nucleus commissuralis) in the cat. A Golgi study.

    PubMed

    Herrera, M; Sánchez del Campo, F; Ruiz, A; Smith Agreda, V

    1988-06-01

    Cell types in the dorsal periaqueductal nucleus (PAGd) were studied with the aid of the rapid Golgi method in young cats. The neurons were subdivided into fusiform and stellate types with several varieties of the latter class according to the final destination of their axons. Fusiform neurons send their axons to the neuropil of the Ncom. In turn these neurons receive descending fibres from the nucleus commissuralis (Ncom) which seem to establish axo-dendritic contacts. Also commissural neurons receive contacts from ascending fibres of the PAGd. On the basis of Golgi material it is concluded that particular neuronal types of the PAGd could establish reciprocal connections with neuronal elements of the ventral part of the Ncom. The present study supports the hypothesis that the PAGd could be subdivided into discrete cell groups according to their afferent and efferent projections.

  9. Parturition Signaling by Visual Cues in Female Marmosets (Callithrix jacchus).

    PubMed

    Moreira, Laís Alves Antonio; de Oliveira, Danilo Gustavo Rodrigues; de Sousa, Maria Bernardete Cordeiro; Pessoa, Daniel Marques Almeida

    2015-01-01

    New World monkeys have polymorphic color vision, in which all males and some females are dichromats, while most females are trichromats. There is little consensus about which selective pressures fashioned primate color vision, although detection of food, mates and predators has been hypothesized. Behavioral evidence shows that males from different species of Neotropical primates seem to perceive the timing of female conception and gestation, although, no signals fulfilling this function have been identified. Therefore, we used visual models to test the hypothesis that female marmosets show chromatic and/or achromatic cues that may indicate the time of parturition for male and female conspecifics. By recording the reflectance spectra of female marmosets' (Callithrix jacchus) sexual skin, and running chromatic and achromatic discrimination models, we found that both variables fluctuate during the weeks that precede and succeed parturition, forming "U" and inverted "U" patterns for chromatic and achromatic contrast, respectively. We suggest that variation in skin chroma and luminance might be used by female helpers and dominant females to identify the timing of birth, while achromatic variations may be used as clues by potential fathers to identify pregnancy stage in females and prepare for paternal burdens as well as to detect oestrus in the early post-partum period. PMID:26047350

  10. Mirror Neurons in a New World Monkey, Common Marmoset.

    PubMed

    Suzuki, Wataru; Banno, Taku; Miyakawa, Naohisa; Abe, Hiroshi; Goda, Naokazu; Ichinohe, Noritaka

    2015-01-01

    Mirror neurons respond when executing a motor act and when observing others' similar act. So far, mirror neurons have been found only in macaques, humans, and songbirds. To investigate the degree of phylogenetic specialization of mirror neurons during the course of their evolution, we determined whether mirror neurons with similar properties to macaques occur in a New World monkey, the common marmoset (Callithrix jacchus). The ventral premotor cortex (PMv), where mirror neurons have been reported in macaques, is difficult to identify in marmosets, since no sulcal landmarks exist in the frontal cortex. We addressed this problem using "in vivo" connection imaging methods. That is, we first identified cells responsive to others' grasping action in a clear landmark, the superior temporal sulcus (STS), under anesthesia, and injected fluorescent tracers into the region. By fluorescence stereomicroscopy, we identified clusters of labeled cells in the ventrolateral frontal cortex, which were confirmed to be within the ventrolateral frontal cortex including PMv after sacrifice. We next implanted electrodes into the ventrolateral frontal cortex and STS and recorded single/multi-units under an awake condition. As a result, we found neurons in the ventrolateral frontal cortex with characteristic "mirror" properties quite similar to those in macaques. This finding suggests that mirror neurons occur in a common ancestor of New and Old World monkeys and its common properties are preserved during the course of primate evolution.

  11. Mirror Neurons in a New World Monkey, Common Marmoset

    PubMed Central

    Suzuki, Wataru; Banno, Taku; Miyakawa, Naohisa; Abe, Hiroshi; Goda, Naokazu; Ichinohe, Noritaka

    2015-01-01

    Mirror neurons respond when executing a motor act and when observing others' similar act. So far, mirror neurons have been found only in macaques, humans, and songbirds. To investigate the degree of phylogenetic specialization of mirror neurons during the course of their evolution, we determined whether mirror neurons with similar properties to macaques occur in a New World monkey, the common marmoset (Callithrix jacchus). The ventral premotor cortex (PMv), where mirror neurons have been reported in macaques, is difficult to identify in marmosets, since no sulcal landmarks exist in the frontal cortex. We addressed this problem using “in vivo” connection imaging methods. That is, we first identified cells responsive to others' grasping action in a clear landmark, the superior temporal sulcus (STS), under anesthesia, and injected fluorescent tracers into the region. By fluorescence stereomicroscopy, we identified clusters of labeled cells in the ventrolateral frontal cortex, which were confirmed to be within the ventrolateral frontal cortex including PMv after sacrifice. We next implanted electrodes into the ventrolateral frontal cortex and STS and recorded single/multi-units under an awake condition. As a result, we found neurons in the ventrolateral frontal cortex with characteristic “mirror” properties quite similar to those in macaques. This finding suggests that mirror neurons occur in a common ancestor of New and Old World monkeys and its common properties are preserved during the course of primate evolution. PMID:26696817

  12. Auditory Artificial Grammar Learning in Macaque and Marmoset Monkeys

    PubMed Central

    Wilson, Benjamin; Slater, Heather; Kikuchi, Yukiko; Milne, Alice E.; Marslen-Wilson, William D.; Smith, Kenny

    2013-01-01

    Artificial grammars (AG) are designed to emulate aspects of the structure of language, and AG learning (AGL) paradigms can be used to study the extent of nonhuman animals' structure-learning capabilities. However, different AG structures have been used with nonhuman animals and are difficult to compare across studies and species. We developed a simple quantitative parameter space, which we used to summarize previous nonhuman animal AGL results. This was used to highlight an under-studied AG with a forward-branching structure, designed to model certain aspects of the nondeterministic nature of word transitions in natural language and animal song. We tested whether two monkey species could learn aspects of this auditory AG. After habituating the monkeys to the AG, analysis of video recordings showed that common marmosets (New World monkeys) differentiated between well formed, correct testing sequences and those violating the AG structure based primarily on simple learning strategies. By comparison, Rhesus macaques (Old World monkeys) showed evidence for deeper levels of AGL. A novel eye-tracking approach confirmed this result in the macaques and demonstrated evidence for more complex AGL. This study provides evidence for a previously unknown level of AGL complexity in Old World monkeys that seems less evident in New World monkeys, which are more distant evolutionary relatives to humans. The findings allow for the development of both marmosets and macaques as neurobiological model systems to study different aspects of AGL at the neuronal level. PMID:24285889

  13. Parturition Signaling by Visual Cues in Female Marmosets (Callithrix jacchus).

    PubMed

    Moreira, Laís Alves Antonio; de Oliveira, Danilo Gustavo Rodrigues; de Sousa, Maria Bernardete Cordeiro; Pessoa, Daniel Marques Almeida

    2015-01-01

    New World monkeys have polymorphic color vision, in which all males and some females are dichromats, while most females are trichromats. There is little consensus about which selective pressures fashioned primate color vision, although detection of food, mates and predators has been hypothesized. Behavioral evidence shows that males from different species of Neotropical primates seem to perceive the timing of female conception and gestation, although, no signals fulfilling this function have been identified. Therefore, we used visual models to test the hypothesis that female marmosets show chromatic and/or achromatic cues that may indicate the time of parturition for male and female conspecifics. By recording the reflectance spectra of female marmosets' (Callithrix jacchus) sexual skin, and running chromatic and achromatic discrimination models, we found that both variables fluctuate during the weeks that precede and succeed parturition, forming "U" and inverted "U" patterns for chromatic and achromatic contrast, respectively. We suggest that variation in skin chroma and luminance might be used by female helpers and dominant females to identify the timing of birth, while achromatic variations may be used as clues by potential fathers to identify pregnancy stage in females and prepare for paternal burdens as well as to detect oestrus in the early post-partum period.

  14. Common marmoset embryonic stem cell can differentiate into cardiomyocytes

    SciTech Connect

    Chen Hao; Hattori, Fumiyuki; Murata, Mitsushige; Li Weizhen; Yuasa, Shinsuke; Onizuka, Takeshi; Shimoji, Kenichiro; Ohno, Yohei; Sasaki, Erika; Kimura, Kensuke; Hakuno, Daihiko

    2008-05-09

    Common marmoset monkeys have recently attracted much attention as a primate research model, and are preferred to rhesus and cynomolgus monkeys due to their small bodies, easy handling and efficient breeding. We recently reported the establishment of common marmoset embryonic stem cell (CMESC) lines that could differentiate into three germ layers. Here, we report that our CMESC can also differentiate into cardiomyocytes and investigated their characteristics. After induction, FOG-2 was expressed, followed by GATA4 and Tbx20, then Nkx2.5 and Tbx5. Spontaneous beating could be detected at days 12-15. Immunofluorescent staining and ultrastructural analyses revealed that they possessed characteristics typical of functional cardiomyocytes. They showed sinus node-like action potentials, and the beating rate was augmented by isoproterenol stimulation. The BrdU incorporation assay revealed that CMESC-derived cardiomyocytes retained a high proliferative potential for up to 24 weeks. We believe that CMESC-derived cardiomyocytes will advance preclinical studies in cardiovascular regenerative medicine.

  15. Dissociation between seeing and acting: insights from common marmosets (Callithrix jacchus).

    PubMed

    Cacchione, Trix; Burkart, Judith Maria

    2012-01-01

    Perception-based measures often reveal much earlier competencies than action-based approaches. We explored this phenomenon generally labeled as "knowledge dissociation" in 28 common marmoset monkeys (Callithrix jacchus) using a paradigm where subjects had to localize a food item dropped down an opaque tube. Experiments 1 and 2 assessed common marmoset monkeys' gravity bias in an action based version of the tubes task. Experiments 3 and 4 investigated whether marmosets' performance increases in an action-free task context where they simply look at objects falling down a tube. The results suggest that common marmosets have some intuition of continuity/solidity constraints when tested with perception based measures even though these principles do not appear to guide their search for falling objects.

  16. Common marmoset as a new model animal for neuroscience research and genome editing technology.

    PubMed

    Kishi, Noriyuki; Sato, Kenya; Sasaki, Erika; Okano, Hideyuki

    2014-01-01

    The common marmoset (Callithrix jacchus) is a small New World primate; it originally comes from the Atlantic coastal forests in northeastern Brazil. It has been attracting much attention in the biomedical research field because of its size, availability, and unique biological characteristics. Its endocrinological and behavioral similarity to humans, comparative ease in handling, and high reproductive efficiency are very advantageous for neuroscience research. Recently, we developed transgenic common marmosets with germline transmission, and this technological breakthrough provides a potential paradigm shift by enabling researchers to investigate complex biological phenomena using genetically-modified non-human primates. In this review, we summarize recent progress in marmoset research, and also discuss a potential application of genome editing tools that should be useful toward the generation of knock-out/knock-in marmoset models.

  17. Neonatal cortical ablation disrupts multisensory development in superior colliculus

    PubMed Central

    Jiang, Wan; Jiang, Huai; Stein, Barry E.

    2006-01-01

    The ability of cat superior colliculus (SC) neurons to synthesize information from different senses depends on influences from two areas of the cortex: the anterior ectosylvian sulcus (AES) and the rostral lateral suprasylvian sulcus (rLS). Reversibly deactivating the inputs to the SC from either of these areas in normal adults severely compromises this ability and the SC-mediated behaviors that depend on it. In the present study we found that removal of these areas in neonatal animals precluded the normal development of multisensory SC processes. At maturity there was a substantial decrease in the incidence of multisensory neurons, and those multisensory neurons that did develop were highly abnormal. Their cross-modal receptive field register was severely compromised, as was their ability to integrate cross-modal stimuli. Apparently, despite the impressive plasticity of the neonatal brain, it cannot compensate for the early loss of these cortices. Surprisingly, however, neonatal removal of either AES or rLS had comparatively minor consequences on these properties. At maturity multisensory SC neurons were quite common: they developed the characteristic spatial register among their unisensory receptive fields and exhibited normal adult-like multisensory integration. These observations suggest that during early ontogeny, when the multisensory properties of SC neurons are being crafted, AES and rLS may have the ability to compensate for the loss of one another’s cortico-collicular influences so that normal multisensory processes can develop in the SC. PMID:16267111

  18. Modeling the value of strategic actions in the superior colliculus.

    PubMed

    Thevarajah, Dhushan; Webb, Ryan; Ferrall, Christopher; Dorris, Michael C

    2010-01-01

    In learning models of strategic game play, an agent constructs a valuation (action value) over possible future choices as a function of past actions and rewards. Choices are then stochastic functions of these action values. Our goal is to uncover a neural signal that correlates with the action value posited by behavioral learning models. We measured activity from neurons in the superior colliculus (SC), a midbrain region involved in planning saccadic eye movements, while monkeys performed two saccade tasks. In the strategic task, monkeys competed against a computer in a saccade version of the mixed-strategy game "matching-pennies". In the instructed task, saccades were elicited through explicit instruction rather than free choices. In both tasks neuronal activity and behavior were shaped by past actions and rewards with more recent events exerting a larger influence. Further, SC activity predicted upcoming choices during the strategic task and upcoming reaction times during the instructed task. Finally, we found that neuronal activity in both tasks correlated with an established learning model, the Experience Weighted Attraction model of action valuation (Camerer and Ho, 1999). Collectively, our results provide evidence that action values hypothesized by learning models are represented in the motor planning regions of the brain in a manner that could be used to select strategic actions.

  19. Modeling the Value of Strategic Actions in the Superior Colliculus

    PubMed Central

    Thevarajah, Dhushan; Webb, Ryan; Ferrall, Christopher; Dorris, Michael C.

    2009-01-01

    In learning models of strategic game play, an agent constructs a valuation (action value) over possible future choices as a function of past actions and rewards. Choices are then stochastic functions of these action values. Our goal is to uncover a neural signal that correlates with the action value posited by behavioral learning models. We measured activity from neurons in the superior colliculus (SC), a midbrain region involved in planning saccadic eye movements, while monkeys performed two saccade tasks. In the strategic task, monkeys competed against a computer in a saccade version of the mixed-strategy game ”matching-pennies”. In the instructed task, saccades were elicited through explicit instruction rather than free choices. In both tasks neuronal activity and behavior were shaped by past actions and rewards with more recent events exerting a larger influence. Further, SC activity predicted upcoming choices during the strategic task and upcoming reaction times during the instructed task. Finally, we found that neuronal activity in both tasks correlated with an established learning model, the Experience Weighted Attraction model of action valuation (Camerer and Ho, 1999). Collectively, our results provide evidence that action values hypothesized by learning models are represented in the motor planning regions of the brain in a manner that could be used to select strategic actions. PMID:20161807

  20. Effect of Reversible Inactivation of Superior Colliculus on Head Movements

    PubMed Central

    Walton, Mark M. G.; Bechara, Bernard; Gandhi, Neeraj J.

    2013-01-01

    Because of limitations in the oculomotor range, many gaze shifts must be accomplished using coordinated movements of the eyes and head. Stimulation and recording data have implicated the primate superior colliculus (SC) in the control of these gaze shifts. The precise role of this structure in head movement control, however, is not known. The present study uses reversible inactivation to gain insight into the role of this structure in the control of head movements, including those that accompany gaze shifts and those that occur in the absence of a change in gaze. Forty-five lidocaine injections were made in two monkeys that had been trained on a series of behavioral tasks that dissociate movements of the eyes and head. Reversible inactivation resulted in clear impairments in the animals’ ability to perform gaze shifts, manifested by increased reaction times, lower peak velocities, and increased durations. In contrast, comparable effects were not found for head movements (with or without gaze shifts) with the exception of a very small increase in reaction times of head movements associated with gaze shifts. Eye-head coordination was clearly affected by the injections with gaze onset occurring relatively later with respect to head onset. Following the injections, the head contributed slightly more to the gaze shift. These results suggest that head movements (with and without gaze shifts) can be controlled by pathways that do not involve SC. PMID:18305088

  1. Neural Prediction of Multidimensional Decisions in Monkey Superior Colliculus

    NASA Astrophysics Data System (ADS)

    Hasegawa, Ryohei P.; Hasegawa, Yukako T.; Segraves, Mark A.

    To examine the function of the superior colliculus (SC) in decision-making processes and the application of its single trial activity for “neural mind reading,” we recorded from SC deep layers while two monkeys performed oculomotor go/no-go tasks. We have recently focused on monitoring single trial activities in single SC neurons, and designed a virtual decision function (VDF) to provide a good estimation of single-dimensional decisions (go/no-go decisions for a cue presented at a specific visual field, a response field of each neuron). In this study, we used two VDFs for multidimensional decisions (go/no-go decisions at two cue locations) with the ensemble activity which was simultaneously recorded from a small group (4 to 6) of neurons at both sides of the SC. VDFs predicted cue locations as well as go/no-go decisions. These results suggest that monitoring of ensemble SC activity had sufficient capacity to predict multidimensional decisions on a trial-by-trial basis, which is an ideal candidate to serve for cognitive brain-machine interfaces (BMI) such as two-dimensional word spellers.

  2. Reunion behavior after social separation is associated with enhanced HPA recovery in young marmoset monkeys.

    PubMed

    Taylor, Jack H; Mustoe, Aaryn C; Hochfelder, Benjamin; French, Jeffrey A

    2015-07-01

    The relationships that offspring develop with caregivers can exert a powerful influence on behavior and physiology, including the hypothalamic-pituitary-adrenal (HPA) axis. In many mammalian species, offspring-caregiver relationships are largely limited to interactions with mother. Marmoset monkeys receive care in early life from multiple classes of caregivers in addition to the mother, including fathers and siblings. We evaluated whether affiliative social interactions with family members in marmosets were associated with differences in cortisol reactivity to a short-term social separation stressor, and whether these variations in affiliative interactions upon reunion predicted how well marmosets subsequently regulated HPA axis function after cessation of the stressor. Marmosets were separated from the family for 8h at three developmental time points (6-, 12-, and 18-months of age), and interactions of the separated marmoset with the family group were recorded during reunion. Urinary cortisol was measured prior to social separation, every 2h during the separation, and on the morning after separation. Heightened cortisol reactivity during social separation did not predict affiliative social behavior upon reunion but higher rates of grooming and play behavior predicted enhanced HPA regulation. Marmosets with higher rates of grooming and play with family members upon reunion had post-stress cortisol levels closer to preseparation baseline than marmosets with lower rates of affiliative reunion behavior. Combined with previous research showing the early programming effects of social interactions with caregivers, as well as the buffering effect of a close social partner during stress, the current study highlights the high degree of behavioral and HPA adaptability to social stressors across development in marmoset monkeys. PMID:25900596

  3. Reunion behavior after social separation is associated with enhanced HPA recovery in young marmoset monkeys.

    PubMed

    Taylor, Jack H; Mustoe, Aaryn C; Hochfelder, Benjamin; French, Jeffrey A

    2015-07-01

    The relationships that offspring develop with caregivers can exert a powerful influence on behavior and physiology, including the hypothalamic-pituitary-adrenal (HPA) axis. In many mammalian species, offspring-caregiver relationships are largely limited to interactions with mother. Marmoset monkeys receive care in early life from multiple classes of caregivers in addition to the mother, including fathers and siblings. We evaluated whether affiliative social interactions with family members in marmosets were associated with differences in cortisol reactivity to a short-term social separation stressor, and whether these variations in affiliative interactions upon reunion predicted how well marmosets subsequently regulated HPA axis function after cessation of the stressor. Marmosets were separated from the family for 8h at three developmental time points (6-, 12-, and 18-months of age), and interactions of the separated marmoset with the family group were recorded during reunion. Urinary cortisol was measured prior to social separation, every 2h during the separation, and on the morning after separation. Heightened cortisol reactivity during social separation did not predict affiliative social behavior upon reunion but higher rates of grooming and play behavior predicted enhanced HPA regulation. Marmosets with higher rates of grooming and play with family members upon reunion had post-stress cortisol levels closer to preseparation baseline than marmosets with lower rates of affiliative reunion behavior. Combined with previous research showing the early programming effects of social interactions with caregivers, as well as the buffering effect of a close social partner during stress, the current study highlights the high degree of behavioral and HPA adaptability to social stressors across development in marmoset monkeys.

  4. Chronic multiscale imaging of neuronal activity in the awake common marmoset

    PubMed Central

    Yamada, Yoshiyuki; Matsumoto, Yoshifumi; Okahara, Norio; Mikoshiba, Katsuhiko

    2016-01-01

    We report a methodology to chronically record in vivo brain activity in the awake common marmoset. Over a month, stable imaging revealed macroscopic sensory maps in the somatosensory cortex and their underlying cellular activity with a high signal-to-noise ratio in the awake but not anesthetized state. This methodology is applicable to other brain regions, and will be useful for studying cortical activity and plasticity in marmosets during learning, development, and in neurological disorders. PMID:27786241

  5. Plasma Metabolomics of Common Marmosets (Callithrix jacchus) to Evaluate Diet and Feeding Husbandry

    PubMed Central

    Banton, Sophia A; Soltow, Quinlyn A; Liu, Ken H; Uppal, Karan; Promislow, Daniel E L; Power, Michael L; Tardif, Suzette D; Wachtman, Lynn M; Jones, Dean P

    2016-01-01

    Common marmosets (Callithrix jacchus) are an important NHP model for the study of human aging and age-related diseases. However, the full potential of marmosets as a research model has not been realized due to a lack of evidence-based, standardized procedures for their captive management, especially regarding diet and feeding husbandry. In the present study, we conducted a high-resolution metabolomics analysis of plasma from marmosets from a 3-mo dietary crossover study to determine whether significant metabolic differences occur with a semisynthetic chemically defined (purified) diet as needed for controlled nutrition research. Marmosets were fed a standard, diverse-ingredient diet, followed by a semisynthetic purified diet, and then were switched back to the standard diet. The standard diet used in this analysis was specific to the animal facility, but it is similar in content to the diets currently used for other marmoset colonies. High-resolution metabolomics of plasma with liquid chromatography–mass spectrometry and bioinformatics was used to measure metabolic differences. The concentration of the essential amino acids methionine, leucine/isoleucine, lysine, and threonine were higher when marmosets were fed the purified diet. In contrast, phenylalanine concentrations were higher during exposure to the standard diet. In addition, metabolic pathway enrichment and analysis revealed differences among metabolites associated with dopamine metabolism and the carnitine shuttle. These results show that diet-associated differences in metabolism occur in marmosets and suggest that additional nutritional studies with detailed physiologic characterization are needed to optimize standard and purified diets for common marmosets. PMID:27025803

  6. Puzzle Feeders and Gum Feeders as Environmental Enrichment for Common Marmosets.

    PubMed

    Roberts, R. Lucille; Roytburd, Luba A.; Newman, John D.

    1999-09-01

    Common marmosets (Callithrix jacchus jacchus) are highly social New World monkeys that consume a principally gummivorous and insectivorous diet. We examined the efficacy of two types of foraging devices, Puzzle-Feeders(tm) and gum feeders, as environmental enrichment for marmosets housed singly (n = 16) or in sibling (n = 4) and heterosexual (n = 8) pairs. In experiment 1, marmosets were exposed to each of the two types of foraging devices for three hours, once per week for two weeks. Thirty-minute observations were conducted at the beginning and end of each exposure period. Marmosets in all housing conditions experienced significant reductions in the frequency of stereotyped pacing and significantly less time sitting still while exposed to the foraging devices. Marmosets experienced significantly lower levels of feeder use and significantly more time sitting still at the end of the three-hour exposure than at the beginning. Marmosets that were singly or sibling housed used the devices the most and had the largest reductions in time spent sitting still during enrichment. In experiment 2, singly housed marmosets were given two types of gum feeders, a wooden and a Gumabone(tm) gum feeder, each for a week-long period. Thirty-minute observations were conducted three times per week immediately after loading the feeders with fresh gum. The wooden gum feeders were heavily gouged during the week-long exposure, although significantly less use of both types of gum feeders was observed on the third and fifth days. These results indicated that marmosets in variable social housing conditions can benefit from environmental enrichment additional to social housing, and that foraging enrichment promotes increased non-stereotyped movement and decreased pacing in this species. PMID:12086412

  7. Behavioral State Dependency of Neural Activity and Sensory (Whisker) Responses in Superior Colliculus

    PubMed Central

    Cohen, Jeremy D.

    2010-01-01

    Rats use their vibrissa (whiskers) to explore and navigate the environment. These sensory signals are distributed within the brain stem by the trigeminal complex and are also relayed to the superior colliculus in the midbrain and to the thalamus (and subsequently barrel cortex) in the forebrain. In the intermediate layers of the superior colliculus, whisker-evoked responses are driven by direct inputs from the trigeminal complex (trigeminotectal) and feedback from the barrel cortex (corticotectal). But the effects of the behavioral state of the animal on the spontaneous firing and sensory responses of these neurons are unknown. By recording from freely behaving rats, we show that the spontaneous firing of whisker sensitive neurons in superior colliculus is higher, or in an activated mode, during active exploration and paradoxical sleep and much lower, or in a quiescent/deactivated mode, during awake immobility and slow-wave sleep. Sensory evoked responses in superior colliculus also depend on behavioral state. Most notably, feedback corticotectal responses are significantly larger during the quiescent/deactivated mode, which tracks the barrel cortex responses on which they depend. Finally, sensory evoked responses depend not only on the state of the animal but also on the orienting response elicited by the stimulus, which agrees with the well known role of the superior colliculus in orienting about salient stimuli. PMID:20610783

  8. Purification and partial characterization of α1-proteinase inhibitor in the common marmoset (Callithrix jacchus)

    PubMed Central

    Parambeth, Joseph Cyrus; Suchodolski, Jan S.; Steiner, Jörg M.

    2015-01-01

    Fecal alpha1-proteinase inhibitor (α1-PI) concentration has been to diagnose enteric protein loss in dogs and cats. Chronic lymphocytic enteritis is commonly seen in the marmoset (C. jaccus) and is characterized by hypoalbuminemia. As a prelude to immunoassay development for detecting enteric protein loss, marmoset serum α1-PI was purified using immunoaffinity chromatography and ceramic hydroxyapatite chromatography. Partial characterization was performed by reducing gel electrophoresis and enzyme inhibitory assays. Protein identity was confirmed with peptide mass fingerprinting and N-terminal amino acid sequencing. Molecular mass, relative molecular mass, and isoelectric point for marmoset α1-PI were 54 kDa, 51677, and 4.8-5.4, respectively. Trypsin, chymotrypsin, and elastase inhibitory activity were observed. N-terminal amino acid sequence for marmoset α1-PI was EDPQGDAAQKMDTSHH. In conclusion, marmoset α1-PI was successfully purified from serum with an overall yield of 12% using a rapid and efficient method. Purified marmoset α1-PI has characteristics similar to those of α1-PI reported for other species. PMID:25745866

  9. A quantitative acoustic analysis of the vocal repertoire of the common marmoset (Callithrix jacchus).

    PubMed

    Agamaite, James A; Chang, Chia-Jung; Osmanski, Michael S; Wang, Xiaoqin

    2015-11-01

    The common marmoset (Callithrix jacchus), a highly vocal New World primate species, has emerged in recent years as a promising animal model for studying brain mechanisms underlying perception, vocal production, and cognition. The present study provides a quantitative acoustic analysis of a large number of vocalizations produced by marmosets in a social environment within a captive colony. Previous classifications of the marmoset vocal repertoire were mostly based on qualitative observations. In the present study a variety of vocalizations from individually identified marmosets were sampled and multiple acoustic features of each type of vocalization were measured. Results show that marmosets have a complex vocal repertoire in captivity that consists of multiple vocalization types, including both simple calls and compound calls composed of sequences of simple calls. A detailed quantification of the vocal repertoire of the marmoset can serve as a solid basis for studying the behavioral significance of their vocalizations and is essential for carrying out studies that investigate such properties as perceptual boundaries between call types and among individual callers as well as neural coding mechanisms for vocalizations. It can also serve as the basis for evaluating abnormal vocal behaviors resulting from diseases or genetic manipulations. PMID:26627765

  10. A quantitative acoustic analysis of the vocal repertoire of the common marmoset (Callithrix jacchus).

    PubMed

    Agamaite, James A; Chang, Chia-Jung; Osmanski, Michael S; Wang, Xiaoqin

    2015-11-01

    The common marmoset (Callithrix jacchus), a highly vocal New World primate species, has emerged in recent years as a promising animal model for studying brain mechanisms underlying perception, vocal production, and cognition. The present study provides a quantitative acoustic analysis of a large number of vocalizations produced by marmosets in a social environment within a captive colony. Previous classifications of the marmoset vocal repertoire were mostly based on qualitative observations. In the present study a variety of vocalizations from individually identified marmosets were sampled and multiple acoustic features of each type of vocalization were measured. Results show that marmosets have a complex vocal repertoire in captivity that consists of multiple vocalization types, including both simple calls and compound calls composed of sequences of simple calls. A detailed quantification of the vocal repertoire of the marmoset can serve as a solid basis for studying the behavioral significance of their vocalizations and is essential for carrying out studies that investigate such properties as perceptual boundaries between call types and among individual callers as well as neural coding mechanisms for vocalizations. It can also serve as the basis for evaluating abnormal vocal behaviors resulting from diseases or genetic manipulations.

  11. Aerosolized rift valley fever virus causes fatal encephalitis in african green monkeys and common marmosets.

    PubMed

    Hartman, Amy L; Powell, Diana S; Bethel, Laura M; Caroline, Amy L; Schmid, Richard J; Oury, Tim; Reed, Douglas S

    2014-02-01

    Rift Valley fever (RVF) is a veterinary and human disease in Africa and the Middle East. The causative agent, RVF virus (RVFV), can be naturally transmitted by mosquito, direct contact, or aerosol. We sought to develop a nonhuman primate (NHP) model of severe RVF in humans to better understand the pathogenesis of RVF and to use for evaluation of medical countermeasures. NHP from four different species were exposed to aerosols containing RVFV. Both cynomolgus and rhesus macaques developed mild fevers after inhalation of RVFV, but no other clinical signs were noted and no macaque succumbed to RVFV infection. In contrast, both marmosets and African green monkeys (AGM) proved susceptible to aerosolized RVF virus. Fever onset was earlier with the marmosets and had a biphasic pattern similar to what has been reported in humans. Beginning around day 8 to day 10 postexposure, clinical signs consistent with encephalitis were noted in both AGM and marmosets; animals of both species succumbed between days 9 and 11 postexposure. Marmosets were susceptible to lower doses of RVFV than AGM. Histological examination confirmed viral meningoencephalitis in both species. Hematological analyses indicated a drop in platelet counts in both AGM and marmosets suggestive of thrombosis, as well as leukocytosis that consisted mostly of granulocytes. Both AGM and marmosets would serve as useful models of aerosol infection with RVFV.

  12. Goal Representations Dominate Superior Colliculus Activity during Extrafoveal Tracking

    PubMed Central

    Hafed, Ziad M.; Krauzlis, Richard J.

    2009-01-01

    The primate superior colliculus (SC) has long been known to be involved in saccade generation. However, SC neurons also exhibit fixation-related and smooth-pursuit-related activity. A parsimonious explanation for these seemingly disparate findings is that the SC contains a map of behaviorally relevant goal locations, rather than just a motor map for saccades and fixation. This explanation predicts that SC activity should reflect the behavioral goal, even when the behavioral response is not fixation or saccades, and even if the goal does not correspond to a visual stimulus. We tested this prediction by employing a tracking task that dissociates the stimulus and goal locations. In this task, monkeys tracked the invisible midpoint between two peripheral bars, such that the visual stimuli were peripheral but the goal was foveal/parafoveal. We recorded from SC neurons representing peripheral locations associated with the stimulus or central locations associated with the goal. Most neurons with peripheral response fields did not respond differently during tracking than during passive viewing of the stimulus under fixation; most neurons with central response fields responded more during tracking than during fixation, despite the lack of a visual stimulus. Moreover, the spatial distribution of activity during tracking was larger than that during fixation or tracking of a foveal stimulus, suggesting that the greater spatial uncertainty about the invisible goal corresponded to more widespread SC activity. These results demonstrate the flexibility with which activity across the SC represents the location - and also the spatial precision - of behaviorally relevant goals for multiple eye movements. PMID:18799675

  13. Similarity of superior colliculus involvement in microsaccade and saccade generation

    PubMed Central

    Krauzlis, Richard J.

    2012-01-01

    The characteristics of microsaccades, or small fixational saccades, and their influence on visual function have been studied extensively. However, the detailed mechanisms for generating these movements are less understood. We recently found that the superior colliculus (SC), a midbrain structure involved in saccade generation, also plays a role in microsaccade generation. Here we compared the dynamics of neuronal activity in the SC associated with microsaccades to those observed in this structure in association with larger voluntary saccades. We found that microsaccade-related activity in the SC is characterized by a gradual increase in firing rate starting ∼100 ms prior to microsaccade onset, a peak of neuronal discharge just after movement onset, and a subsequent gradual decrease in firing rate until ∼100 ms after movement onset. These properties were shared with saccade-related SC neurons, recorded from the same monkeys but preferring larger eye movements, suggesting that at the level of the SC the neuronal control of microsaccades is similar to that for larger voluntary saccades. We also found that neurons exhibiting microsaccade-related activity often also exhibited saccade-related activity for slightly larger movements of similar direction, suggesting a continuity of the spatial representation in the SC, in both amplitude and direction, down to the smallest movements. Our results indicate that the mechanisms controlling microsaccades may be fundamentally the same as those for larger saccades, and thus shed new light on the functional role of these eye movements and their possible influence on sensory and sensory-motor processes. PMID:22236714

  14. NKG2D functions as an activating receptor on natural killer cells in the common marmoset (Callithrix jacchus).

    PubMed

    Watanabe, Masamichi; Kudo, Yohei; Kawano, Mitsuko; Nakayama, Masafumi; Nakamura, Kyohei; Kameda, Mai; Ebara, Masamune; Sato, Takeki; Nakamura, Marina; Omine, Kaito; Kametani, Yoshie; Suzuki, Ryuji; Ogasawara, Kouetsu

    2014-11-01

    The natural killer group 2 membrane D (NKG2D) receptor is an NK-activating receptor that plays an important role in host defense against tumors and viral infections. Although the marmoset is an important and reliable animal model, especially for the study of human-specific viral infections, functional characterization of NKG2D on marmoset NK cells has not previously been conducted. In the present study, we investigated a subpopulation of marmoset NK cells that express NKG2D and exhibit cytolytic potential. On the basis of their CD16 and CD56 expression patterns, marmoset NK cells can be classified into three subpopulations: CD16(+) CD56(-), CD16(-) CD56(+) and CD16(-) CD56(-) cells. NKG2D expression on marmoset CD16(+) CD56(-) and CD16(-) CD56(+) splenocytes was confirmed using an NKG2D ligand composed of an MHC class I chain-related molecule A (MICA)-Fc fusion protein. When marmoset splenocytes were cultured with IL-2 for 4 days, NKG2D expression was retained on CD16(+) CD56(-) and CD16(-) CD56(+). In addition, CD16(+) CD56(+) cells within the marmoset NK population appeared which expressed NKG2D after IL-2 stimulation. IL-2-activated marmoset NK cells showed strong cytolytic activity against K562 target cells and target cells stably expressing MICA. Further, the cytolytic activity of marmoset splenocytes was significantly reduced after addition of MICA-Fc fusion protein. Thus, NKG2D functions as an activating receptor on marmoset NK cells that possesses cytotoxic potential, and phenotypic profiles of marmoset NK cell subpopulations are similar to those seen in humans. PMID:24860119

  15. Histopathological characterization of renal tubular and interstitial changes in 5/6 nephrectomized marmoset monkeys (Callithrix jacchus).

    PubMed

    Suzuki, Yui; Yamaguchi, Itaru; Myojo, Kensuke; Kimoto, Naoya; Imaizumi, Minami; Takada, Chie; Sanada, Hiroko; Takaba, Katsumi; Yamate, Jyoji

    2015-01-01

    Common marmosets (Callithrix jacchus) have become a useful animal model, particularly for development of biopharmaceuticals. While various renal failure models have been established in rodents, there is currently no acceptable model in marmosets. We analyzed the damaged renal tubules and tubulointerstitial changes (inflammation and fibrosis) of 5/6 nephrectomized (Nx) common marmosets by histopathological/immunohistochemical methods, and compared these findings to those in 5/6 Nx SD rats. In Nx marmosets and rats sacrificed at 5 and 13 weeks after Nx, variously dilated and atrophied renal tubules were seen in the cortex in common; however, the epithelial proliferating activity was much less in Nx marmosets. Furthermore, the degrees of inflammation and fibrosis seen in the affected cortex were more severe and massive in Nx marmosets with time-dependent increase. Interestingly, inflammation in Nx marmosets, of which degree was less in Nx rats, consisted of a large number of CD3-positive T cells and CD20-positive B cells (occasionally forming follicles), and a few CD68-positive macrophages. Based on these findings, lymphocytes might contribute to the progressive renal lesions in Nx marmosets. Fibrotic areas in Nx marmosets comprised myofibroblasts expressing vimentin and α-smooth muscle actin (α-SMA), whereas along with vimentin and α-SMA expressions, desmin was expressed in myofibroblasts in Nx rats. This study shows that there are some differences in renal lesions induced by Nx between marmosets and rats, which would provide useful, base-line information for pharmacology and toxicology studies using Nx marmosets. PMID:25446802

  16. "What's wrong with my monkey?" Ethical perspectives on germline transgenesis in marmosets.

    PubMed

    Olsson, I Anna S; Sandøe, Peter

    2010-04-01

    The birth of the first transgenic primate to have inherited a transgene from its parents opens the possibility to set up transgenic marmoset colonies, as these monkeys are small and relatively easy to keep and breed in research facilities. The prospect of transgenic marmoset models of human disease, readily available in the way that transgenic laboratory mice are currently, prompts excitement in the scientific community; but the idea of monkeys being bred to carry diseases is also contentious. We structure an ethical analysis of the transgenic marmoset case around three questions: whether it is acceptable to use animals as models of human disease; whether it is acceptable to genetically modify animals; and whether these animals' being monkeys makes a difference. The analysis considers the prospect of transgenic marmoset studies coming to replace transgenic mouse studies and lesion studies in marmosets in some areas of research. The mainstream, broadly utilitarian view of animal research suggests that such a transition will not give rise to greater ethical problems than those presently faced. It can be argued that using marmosets rather than mice will not result in more animal suffering, and that the benefits of research will improve with a move to a species more similar in phylogenetic terms to humans. The biological and social proximity of monkeys and humans may also benefit the animals by making it easier for scientists and caretakers to recognize signs of suffering and increasing the human motivation to limit it. The animal welfare and research impacts of the transition to marmoset use will depend very much on the extent to which researchers take these issues seriously and seek to minimize animal harm and optimize human benefit.

  17. Temporal bone characterization and cochlear implant feasibility in the common marmoset (Callithrix jacchus).

    PubMed

    Johnson, Luke A; Della Santina, Charles C; Wang, Xiaoqin

    2012-08-01

    The marmoset (Callithrix jacchus) is a valuable non-human primate model for studying behavioral and neural mechanisms related to vocal communication. It is also well suited for investigating neural mechanisms related to cochlear implants. The purpose of this study was to characterize marmoset temporal bone anatomy and investigate the feasibility of implanting a multi-channel intracochlear electrode into the marmoset scala tympani. Micro computed tomography (microCT) was used to create high-resolution images of marmoset temporal bones. Cochlear fluid spaces, middle ear ossicles, semicircular canals and the surrounding temporal bone were reconstructed in three-dimensional space. Our results show that the marmoset cochlea is ∼16.5 mm in length and has ∼2.8 turns. The cross-sectional area of the scala tympani is greatest (∼0.8 mm(2)) at ∼1.75 mm from the base of the scala, reduces to ∼0.4 mm(2) at 5 mm from the base, and decreases at a constant rate for the remaining length. Interestingly, this length-area profile, when scaled 2.5 times, is similar to the scala tympani of the human cochlea. Given these dimensions, a compatible multi-channel implant electrode was identified. In a cadaveric specimen, this electrode was inserted ¾ turn into the scala tympani through a cochleostomy at ∼1 mm apical to the round window. The depth of the most apical electrode band was ∼8 mm. Our study provides detailed structural anatomy data for the middle and inner ear of the marmoset, and suggests the potential of the marmoset as a new non-human primate model for cochlear implant research. PMID:22583919

  18. Strength of hand preference and dual task performance by common marmosets.

    PubMed

    Piddington, T; Rogers, L J

    2013-01-01

    Study of avian and piscine species has shown that animals with stronger lateralization of the brain are able to perform two tasks presented simultaneously better than can animals with weaker lateralization. We investigated whether this might apply also to primates by testing common marmosets to see whether there is a relationship between the strength of hand preference, as an indicator of strength of brain lateralization, and the ability to carry out two tasks simultaneously. A model predator was introduced into the testing room while the marmoset was foraging. Marmosets with stronger hand preferences detected the 'predator' after shorter latency than those with weaker hand preferences. Furthermore, the marmosets with stronger hand preferences produced more mobbing (tsik) vocalizations when they reacted to the predators than did those with weaker hand preferences. There was no such association between hand preference and either latency to respond to the predator or mobbing reaction when the marmosets were not foraging at the time the predator was introduced. Hence, strength of lateralization is associated with the ability to perform foraging and predator detection simultaneously. These results are discussed with reference to the evolution of brain lateralization. PMID:23053795

  19. Acoustic analysis of vocal development in a New World primate, the common marmoset (Callithrix jacchus).

    PubMed

    Pistorio, Ashley L; Vintch, Brett; Wang, Xiaoqin

    2006-09-01

    In contrast to humans and songbirds, there is limited evidence of vocal learning in nonhuman primates. While previous studies suggested that primate vocalizations exhibit developmental changes, detailed analyses of the extent and time course of such changes across a species' vocal repertoire remain limited. In a highly vocal primate, the common marmoset (Callithrix jacchus), we studied developmental changes in the acoustic structure of species-specific communication sounds produced in a social setting. We performed detailed acoustic analyses of the spectral and temporal characteristics of marmoset vocalizations during development, comparing differences between genders and twin pairs, as well as with vocalizations from adult marmosets residing in the same colony. Our analyses revealed significant changes in spectral and temporal features as well as variability of particular call types over time. Infant and juvenile vocalizations changed progressively toward the vocalizations produced by adult marmosets. Call types observed early in development that were unique to infants disappeared gradually with age, while vocal exchanges with conspecifics emerged. Our observations clearly indicate that marmoset vocalizations undergo both qualitative and quantitative postnatal changes, establishing the basis for further studies to delineate contributions from maturation of the vocal apparatus and behavioral experience.

  20. Mitogenic response of marmoset lymphocytes: cytokinetics and identification of responsive cells*

    PubMed Central

    Kateley, J. R.; Nickerson, Deborah A.; Gengozian, N.

    1977-01-01

    Isotope (tritiated thymidine, [3H]Tdr) incorporation into lymphocytes from two marmoset species, New World primates which are haemopoietic chimeras, was studied using peripheral blood lymphocyte (PBL) cultures incubated in vitro for 1–5 days with different concentrations of Concanavalin A (Con A), leucoagglutinin (LA), bacterial lipopolysaccharide (LPS) from gram-negative bacteria, rabbit anti-marmoset immunoglobulin (anti-Ig) serum, thymosin or irradiated histoincompatible (xenogeneic) lymphocytes. Only the plant lectins and xenogeneic lymphoid cells stimulated the uptake of [3H]Tdr. Lymphocyte enrichment experiments demonstrated that cells responsive to plant lectins and xenoantigens were primarily thymus-derived (T) lymphocytes. Bacterial endotoxin (LPS), however, enhanced the mitogenic response of PBL to Con A when LPS and plant lectin were added together at culture initiation. Thymosin caused either enhancement or suppression of the response to Con A depending on its time of addition relative to lectin stimulation. Addition of thymosin to lymphocyte cultures with Con A or 24 h later caused a decrease in isotope incorporation, while addition of thymosin 48 h later caused a 12–100% increase in [3H]Tdr uptake. Lymphocyte chimerism did not influence the mitogenic response since single-born, nonchimeric marmosets responded to plant lectins in a manner similar to marmosets with varying proportions of chimeric blood elements. Cytological analysis of stimulated lymphocytes from heterosexual marmosets revealed the percentage chimerism in the polyclonal mitogenic response and the clonal mixed lymphocyte reaction to be similar. PMID:145405

  1. Marmoset species variation in the humoral antibody response: in vivo and in vitro studies.

    PubMed Central

    Gengozian, N; Kateley, J R; Nickerson, D A

    1978-01-01

    A comparison of the in vivo and in vitro antibody response capabilities of two marmoset species, Saguinus fuscicollis and Saguinus oedipus oedipus, revealed the former to be superior in elaborating humoral antibody. In vivo challenges with Escherichia coli lipopolysaccharide (LPS) and Salmonella typhi flagella consistently yielded higher antibody titres in S. fuscicollis; indeed, with LPS antigen, multiple inoculations of S.o. oedipus marmosets led ultimately to a decrease in antibody formation, in contrast to the anamnestic response of S. fuscicollis. This species differential in immune competence was also suggested in the in vitro stimulation of peripheral blood leucocytes (PBL) and spleen cells with sheep red blood cells (RBC). None of 55 S.o. oedipus PBL cultures and 49 of 89 (55%) S. fuscicollis cultures responded to the test antigen. A similar differential in response to sheep RBC was noted with the spleen cells of each species, although this report contrasts the antibody-forming potential of two marmoset species, a comparison of the immunological response profile of marmosets to those of other laboratory animals challenged with similar antigens suggests these primates may be relatively incompetent. The possible relationship between the haemopoietic chimerism of marmosets and a diminished immune competence is discussed. PMID:100417

  2. Simulation of the Inferior Mirage

    NASA Astrophysics Data System (ADS)

    Branca, Mario

    2010-09-01

    A mirage can occur when a continuous variation in the refractive index of the air causes light rays to follow a curved path. As a result, the image we see is displaced from the location of the object. If the image appears higher in the air than the object, it is called a "superior" mirage, while if it appears lower it is called an "inferior" mirage.2 The most common example of an inferior mirage is when, on a hot day, a stretch of dry road off in the distance appears to be wet (see Fig. 1). Many lab activities have been described that simulate the formation of superior mirages. In these demonstrations light beams curve downward as they pass through a nonuni-form fluid.3-6 Much less common are laboratory demonstrations of upward-curving light rays of the kind responsible for inferior mirages. This paper describes a simple version of such a demonstration.

  3. Single-born marmosets without hemopoietic chimerism: naturally occurring and induced.

    PubMed

    Gengozian, N; Batson, J S

    1975-01-01

    Marmosets have a high frequency of fraternal twinning, and placental vascular anastomoses between the twin fetuses invariably lead to hemopoietic chimerism. The occasional finding of chimerism in single-born marmosets suggested that in a twin pregnancy one fetus had undergone resorption after contributing hemopoietic stem cells to its twin. In this study non-chimeric single-born marmosets were produced by fallopian tube ligation or surgical relocation of one ovary in breeding females. Further, in an examination of hemopoietic cells from over 50 single-born young from nonoperated females, chimerism occurred less frequently than what one would expect if resorption of a co-twin had occurred after a functional anastomosis had been established. PMID:808628

  4. Evaluation of ultrasonic vocalizations in common marmosets (Callithrix jacchus) as a potential indicator of welfare.

    PubMed

    Bakker, Jaco; van Nijnatten, Tessa J M; Louwerse, Annet L; Baarends, Guus; Arndt, Saskia S; Langermans, Jan A M

    2014-09-01

    The vocal repertoire in common marmosets (Callithrix jacchus) has been assumed to consist not only of vocalizations audible to humans but also of ultrasonic vocalizations (USVs). The use of USVs to socially indicate distress has not been evaluated in this species, however. The authors analyzed the ultrasonic vocal repertoire of the common marmoset under normal housing conditions, under various experimental manipulations intended to elicit positive or negative emotional responses and during stressful experiences including blood draw and exposure to a perceived predator. Analysis of the recordings showed that marmosets produced vocalizations with ultrasonic components as part of their normal vocal repertoire, but these vocalizations all have audible components as well. Only 4 of the 13 types of vocalizations had ultrasonic components. These ultrasonic components were not reliably associated with responses to different experimental manipulations, suggesting that they are not used to indicate pain, discomfort or distress. PMID:25141062

  5. Elucidating coding of taste qualities with the taste modifier miraculin in the common marmoset.

    PubMed

    Danilova, Vicktoria; Hellekant, Göran

    2006-01-30

    To investigate the relationships between the activity in different types of taste fibers and the gustatory behavior in marmosets, we used the taste modifier miraculin, which in humans adds a sweet taste quality to sour stimuli. In behavioral experiments, we measured marmosets' consumption of acids before and after tongue application of miraculin. In electrophysiological experiments responses of single taste fibers in chorda tympani and glossopharyngeal nerves were recorded before and after tongue application of miraculin. We found that after miraculin marmosets consumed acids more readily. Taste nerve recordings showed that after miraculin taste fibers which usually respond only to sweeteners, S fibers, became responsive to acids. These results further support our hypothesis that the activity in S fibers is translated into a hedonically positive behavioral response. PMID:16377437

  6. Development of a novel postnatal neurobehavioral scale for evaluation of common marmoset monkeys.

    PubMed

    Braun, Katarina; Schultz-Darken, Nancy; Schneider, Mary; Moore, Colleen F; Emborg, Marina E

    2015-04-01

    Common marmoset (Callithrix jacchus) monkeys when compared to rhesus macaques (Macaca mullatta) present several advantages for disease modeling, especially transgenic initiatives, as they commonly give birth to twins, which increases sample size, have accelerated development and a shorter life span that facilitates the analysis of the onset of age-related diseases. Yet, no tools are currently available to assess marmoset neurodevelopment during the initial first month of life. Here we report the creation of a novel Primate Postnatal Neurobehavioral Assessment Scale for marmoset monkeys (PPNAS-M) that was based on currently available scales for human and rhesus monkeys. Twenty-four healthy marmoset infants (12 females, 12 males) from 12 families were evaluated. The infant assessments involved 10-minute testing administered at 15 and 30 days after birth. The PPNAS-M consists of 41 noninvasive tests grouped into 5 testing categories: visual orienting, auditory and spatial orienting, motor responses, righting and body strength, and temperament tests. Testing at these two ages did not affect the overall health of the infants, suggesting that the PPNAS-M is a non-invasive testing tool. Significant maturation was demonstrated by increased scores in each of the five testing categories from postnatal day 15 to 30, with developmental patterns unique to marmosets. Principal component analysis defined 4 item groups (Orientation, State Control, Motor Maturity and Sensory Sensitivity) with 5 variables each. Orientation and State Control factors were highly similar to each other at both ages and correlated highly with previous item groupings used with rhesus macaques. Our results indicate that the PPNAS-M is a useful assessment tool for detecting neuromotor, attention, and temperament status of infant marmosets and that it is sensitive to developmental effects. Further studies to validate the PPNAS-M for the assessment of normal development versus early effects of developmental

  7. DEVELOPMENT OF A NOVEL POSTNATAL NEUROBEHAVIORAL SCALE FOR EVALUATION OF COMMON MARMOSET MONKEYS

    PubMed Central

    Schneider, Mary; Moore, Colleen F.; Emborg, Marina E.

    2014-01-01

    Common marmoset (Callithrix jacchus) monkeys when compared to rhesus macaques (Macaca mullatta) present several advantages for disease modeling, especially transgenic initiatives, as they commonly give birth to twins, which increases sample size, have accelerated development and a shorter life span that facilitates the analysis of the onset of age-related diseases. Yet, no tools are currently available to assess marmoset neurodevelopment during the initial first month of life. Here we report the creation of a novel Primate Postnatal Neurobehavioral Assessment Scale for marmoset monkeys (PPNAS-M) that was based on currently available scales for human and rhesus monkeys. Twenty-four healthy marmoset infants (12 females, 12 males) from 12 families were evaluated. The infant assessments involved 10-minute testing administered at 15 and 30 days after birth. The PPNAS-M consists of 41 noninvasive tests grouped into 5 testing categories: visual orienting, auditory and spatial orienting, motor responses, righting and body strength, and temperament tests. Testing at these two ages did not affect the overall health of the infants, suggesting that the PPNAS-M is a non-invasive testing tool. Significant maturation was demonstrated by increased scores in each of the five testing categories from postnatal day 15 to 30, with developmental patterns unique to marmosets. Principal component analysis defined 4 item groups (Orientation, State Control, Motor Maturity and Sensory Sensitivity) with 5 variables each. Orientation and State Control factors were highly similar at both ages and correlated highly with previous item groupings used with rhesus macaques. Our results indicate that the PPNAS-M is a useful assessment tool for detecting neuromotor, attention, and temperament status of infant marmosets and that it is sensitive to developmental effects. Further studies to validate the PPNAS-M for the assessment of normal development versus early effects of developmental perturbations

  8. Colonization of collagen scaffolds by adipocytes derived from mesenchymal stem cells of the common marmoset monkey

    SciTech Connect

    Bernemann, Inga; Mueller, Thomas; Blasczyk, Rainer; Glasmacher, Birgit; Hofmann, Nicola

    2011-07-29

    Highlights: {yields} Marmoset bone marrow-derived MSCs differentiate in suspension into adipogenic, osteogenic and chondrogenic lineages. {yields} Marmoset MSCs integrate in collagen type I scaffolds and differentiate excellently into adipogenic cells. {yields} Common marmoset monkey is a suitable model for soft tissue engineering in human regenerative medicine. -- Abstract: In regenerative medicine, human cell replacement therapy offers great potential, especially by cell types differentiated from immunologically and ethically unproblematic mesenchymal stem cells (MSCs). In terms of an appropriate carrier material, collagen scaffolds with homogeneous pore size of 65 {mu}m were optimal for cell seeding and cultivating. However, before clinical application and transplantation of MSC-derived cells in scaffolds, the safety and efficiency, but also possible interference in differentiation due to the material must be preclinically tested. The common marmoset monkey (Callithrix jacchus) is a preferable non-human primate animal model for this aim due to its genetic and physiological similarities to the human. Marmoset bone marrow-derived MSCs were successfully isolated, cultured and differentiated in suspension into adipogenic, osteogenic and chondrogenic lineages by defined factors. The differentiation capability could be determined by FACS. Specific marker genes for all three cell types could be detected by RT-PCR. Furthermore, MSCs seeded on collagen I scaffolds differentiated in adipogenic lineage showed after 28 days of differentiation high cell viability and homogenous distribution on the material which was validated by calcein AM and EthD staining. As proof of adipogenic cells, the intracellular lipid vesicles in the cells were stained with Oil Red O. The generation of fat vacuoles was visibly extensive distinguishable and furthermore determined on the molecular level by expression of specific marker genes. The results of the study proved both the differential

  9. A combined histological and MRI brain atlas of the common marmoset monkey, Callithrix jacchus.

    PubMed

    Newman, John D; Kenkel, William M; Aronoff, Emily C; Bock, Nicholas A; Zametkin, Molly R; Silva, Afonso C

    2009-12-11

    The common marmoset, Callithrix jacchus, is of growing importance for research in neuroscience and related fields. In the present work, we describe a combined histological and magnetic resonance imaging (MRI) atlas constructed from the brains of two adult female marmosets. Histological sections were processed from Nissl staining and digitized to produce an atlas in a large format that facilitates visualization of structures with significant detail. Naming of identifiable brain structures was performed utilizing current terminology. The histological sections and a simplified schematic atlas are available online at http://udn.nichd.nih.gov/brainatlas_home.html.

  10. Exchanging grooming, but not tolerance and aggression in common marmosets (Callithrix jacchus).

    PubMed

    Campennì, Marco; Manciocco, Arianna; Vitale, Augusto; Schino, Gabriele

    2015-02-01

    In this study, we investigated the reciprocal exchanges of grooming, tolerance and reduced aggression in common marmosets (Callithrix jacchus), a cooperatively breeding primate whose groups are typically characterized by uniformly high genetic relatedness and high interdependency between group members. Both partner control and partner choice processes played a role in the reciprocal exchanges of grooming. In contrast, we did not find any evidence of reciprocity between grooming and tolerance over a preferred food source or between grooming and reduced aggression. Thus, reciprocity seems to play a variable role in the exchange of cooperative behaviors in marmosets.

  11. HIV-1 Adapts To Replicate in Cells Expressing Common Marmoset APOBEC3G and BST2

    PubMed Central

    Fernández-Oliva, Alberto; Finzi, Andrés; Haim, Hillel; Menéndez-Arias, Luis; Sodroski, Joseph

    2015-01-01

    ABSTRACT Previous studies have shown that a major block to HIV-1 replication in common marmosets operates at the level of viral entry and that this block can be overcome by adaptation of the virus in tissue-cultured cells. However, our current studies indicate that HIV-1 encounters additional postentry blocks in common marmoset peripheral blood mononuclear cells. Here, we show that the common marmoset APOBEC3G (A3G) and BST2 proteins block HIV-1 in cell cultures. Using a directed-evolution method that takes advantage of the natural ability of HIV-1 to mutate during replication, we have been able to overcome these blocks in tissue-cultured cells. In the adapted viruses, specific changes were observed in gag, vif, env, and nef. The contribution of these changes to virus replication in the presence of the A3G and BST2 restriction factors was studied. We found that certain amino acid changes in Vif and Env that arise during adaptation to marmoset A3G and BST2 allow the virus to replicate in the presence of these restriction factors. The changes in Vif reduce expression levels and encapsidation of marmoset APOBEC3G, while the changes in Env increase viral fitness and discretely favor cell-to-cell transmission of the virus, allowing viral escape from these restriction factors. IMPORTANCE HIV-1 can infect only humans and chimpanzees. The main reason for this narrow tropism is the presence in many species of dominant-acting factors, known as restriction factors, that block viral replication in a species-specific way. We have been exploring the blocks to HIV-1 in common marmosets, with the ultimate goal of developing a new animal model of HIV-1 infection in these monkeys. In this study, we observed that common marmoset APOBEC3G and BST2, two known restriction factors, are able to block HIV-1 in cell cultures. We have adapted HIV-1 to replicate in the presence of these restriction factors and have characterized the mechanisms of escape. These studies can help in the

  12. Parturition Signaling by Visual Cues in Female Marmosets (Callithrix jacchus)

    PubMed Central

    Moreira, Laís Alves Antonio; de Oliveira, Danilo Gustavo Rodrigues; de Sousa, Maria Bernardete Cordeiro; Pessoa, Daniel Marques Almeida

    2015-01-01

    New World monkeys have polymorphic color vision, in which all males and some females are dichromats, while most females are trichromats. There is little consensus about which selective pressures fashioned primate color vision, although detection of food, mates and predators has been hypothesized. Behavioral evidence shows that males from different species of Neotropical primates seem to perceive the timing of female conception and gestation, although, no signals fulfilling this function have been identified. Therefore, we used visual models to test the hypothesis that female marmosets show chromatic and/or achromatic cues that may indicate the time of parturition for male and female conspecifics. By recording the reflectance spectra of female marmosets’ (Callithrix jacchus) sexual skin, and running chromatic and achromatic discrimination models, we found that both variables fluctuate during the weeks that precede and succeed parturition, forming “U” and inverted “U” patterns for chromatic and achromatic contrast, respectively. We suggest that variation in skin chroma and luminance might be used by female helpers and dominant females to identify the timing of birth, while achromatic variations may be used as clues by potential fathers to identify pregnancy stage in females and prepare for paternal burdens as well as to detect oestrus in the early post-partum period. PMID:26047350

  13. Structure and function of the middle temporal visual area (MT) in the marmoset: Comparisons with the macaque monkey.

    PubMed

    Lui, Leo L; Rosa, Marcello G P

    2015-04-01

    Although macaque monkeys have been dominant models in visual neuroscience, recent scientific advances suggest that marmosets provide a valuable alternative in the context of many types of experiments. Here we focus on the middle temporal area (MT), the most extensively studied extrastriate area in primates, and discuss similarities and differences between marmosets and macaques. The basic response properties of MT cells are similar in these species, including direction selectivity, speed tuning, and receptive field centre-surround organization. However, there are differences associated with spatial processing: receptive fields are larger in the marmoset than in the macaque, and MT neurons have preferences for lower spatial frequencies. Comparative analysis of anatomical connections show neural projections from several higher-order association areas to marmoset MT, which seem to be absent or reduced in the macaque. This suggests that cognitive processes could influence the activity of marmoset MT cells more directly. Despite a relative reduction in visual acuity, the present knowledge about the anatomy and physiology of MT in the marmoset suggests that simple low-level visual tasks, which are standard in the literature, are well within the capabilities of marmosets, opening the way for comparative studies of perception and cognition in primate brains of different sizes.

  14. Muscle contractile properties as an explanation of the higher mean power output in marmosets than humans during jumping.

    PubMed

    Plas, Rogier L C; Degens, Hans; Meijer, J Peter; de Wit, Gerard M J; Philippens, Ingrid H C H M; Bobbert, Maarten F; Jaspers, Richard T

    2015-07-01

    The muscle mass-specific mean power output (PMMS,mean) during push-off in jumping in marmosets (Callithrix jacchus) is more than twice that in humans. In the present study it was tested whether this is attributable to differences in muscle contractile properties. In biopsies of marmoset m. vastus lateralis (VL) and m. gastrocnemius medialis (GM) (N=4), fibre-type distribution was assessed using fluorescent immunohistochemistry. In single fibres from four marmoset and nine human VL biopsies, the force-velocity characteristics were determined. Marmoset VL contained almost exclusively fast muscle fibres (>99.0%), of which 63% were type IIB and 37% were hybrid fibres, fibres containing multiple myosin heavy chains. GM contained 9% type I fibres, 44% type IIB and 47% hybrid muscle fibres. The proportions of fast muscle fibres in marmoset VL and GM were substantially larger than those reported in the corresponding human muscles. The curvature of the force-velocity relationships of marmoset type IIB and hybrid fibres was substantially flatter than that of human type I, IIA, IIX and hybrid fibres, resulting in substantially higher muscle fibre mass-specific peak power (PFMS,peak). Muscle mass-specific peak power output (PMMS,peak) values of marmoset whole VL and GM, estimated from their fibre-type distributions and force-velocity characteristics, were more than twice the estimates for the corresponding human muscles. As the relative difference in estimated PMMS,peak between marmosets and humans is similar to that of PMMS,mean during push-off in jumping, it is likely that the difference in in vivo mechanical output between humans and marmosets is attributable to differences in muscle contractile properties.

  15. Simulation of the Inferior Mirage

    ERIC Educational Resources Information Center

    Branca, Mario

    2010-01-01

    A mirage can occur when a continuous variation in the refractive index of the air causes light rays to follow a curved path. As a result, the image we see is displaced from the location of the object. If the image appears higher in the air than the object, it is called a "superior" mirage, while if it appears lower it is called an "inferior"…

  16. Functional Mapping of Face-Selective Regions in the Extrastriate Visual Cortex of the Marmoset

    PubMed Central

    Hung, Chia-Chun; Yen, Cecil C.; Ciuchta, Jennifer L.; Papoti, Daniel; Bock, Nicholas A.; Leopold, David A.

    2015-01-01

    The cerebral cortex of humans and macaques has specialized regions for processing faces and other visual stimulus categories. It is unknown whether a similar functional organization exists in New World monkeys, such as the common marmoset (Callithrix jacchus), a species of growing interest as a primate model in neuroscience. To address this question, we measured selective neural responses in the brain of four awake marmosets trained to fix their gaze upon images of faces, bodies, objects, and control patterns. In two of the subjects, we measured high gamma-range field potentials from electrocorticography arrays implanted over a large portion of the occipital and inferotemporal cortex. In the other two subjects, we measured BOLD fMRI responses across the entire brain. Both techniques revealed robust, regionally specific patterns of category-selective neural responses. We report that at least six face-selective patches mark the occipitotemporal pathway of the marmoset, with the most anterior patches showing the strongest preference for faces over other stimuli. The similar appearance of these patches to previous findings in macaques and humans, including their apparent arrangement in two parallel pathways, suggests that core elements of the face processing network were present in the common anthropoid primate ancestor living ∼35 million years ago. The findings also identify the marmoset as a viable animal model system for studying specialized neural mechanisms related to high-level social visual perception in humans. PMID:25609630

  17. Measurement of absolute auditory thresholds in the common marmoset (Callithrix jacchus)

    PubMed Central

    Osmanski, Michael S.; Wang, Xiaoqin

    2011-01-01

    The common marmoset is a small, arboreal, New World primate that has emerged as a promising non-human model system in auditory neuroscience. A complete understanding of the neuroethology of auditory processing in marmosets will include behavioral work examining how sounds are perceived by these animals. However, there have been few studies of the marmoset’s hearing and perceptual abilities and the audiogram of this species has not been measured using modern psychophysical methods. The present experiment pairs psychophysics with an operant conditioning technique to examine perception of pure tone stimuli by marmosets using an active behavioral paradigm. Subjects were trained to lick at a feeding tube when they detected a sound. Correct responses provided access to a food reward. Pure tones of varying intensities were presented to subjects using the method of constant stimuli. Behavioral thresholds were calculated for each animal based on hit rate - threshold was defined by the tone intensity that the animal correctly identified 50% of the time. Results show that marmoset hearing is comparable to that of other New World monkeys, with a hearing range extending from about 125 Hz up to 36 kHz and a sensitivity peak around 7 kHz. PMID:21303689

  18. Early development of turn-taking with parents shapes vocal acoustics in infant marmoset monkeys.

    PubMed

    Takahashi, Daniel Y; Fenley, Alicia R; Ghazanfar, Asif A

    2016-05-01

    In humans, vocal turn-taking is a ubiquitous form of social interaction. It is a communication system that exhibits the properties of a dynamical system: two individuals become coupled to each other via acoustic exchanges and mutually affect each other. Human turn-taking develops during the first year of life. We investigated the development of vocal turn-taking in infant marmoset monkeys, a New World species whose adult vocal behaviour exhibits the same universal features of human turn-taking. We find that marmoset infants undergo the same trajectory of change for vocal turn-taking as humans, and do so during the same life-history stage. Our data show that turn-taking by marmoset infants depends on the development of self-monitoring, and that contingent parental calls elicit more mature-sounding calls from infants. As in humans, there was no evidence that parental feedback affects the rate of turn-taking maturation. We conclude that vocal turn-taking by marmoset monkeys and humans is an instance of convergent evolution, possibly as a result of pressures on both species to adopt a cooperative breeding strategy and increase volubility. PMID:27069047

  19. A simpler primate brain: the visual system of the marmoset monkey

    PubMed Central

    Solomon, Samuel G.; Rosa, Marcello G. P.

    2014-01-01

    Humans are diurnal primates with high visual acuity at the center of gaze. Although primates share many similarities in the organization of their visual centers with other mammals, and even other species of vertebrates, their visual pathways also show unique features, particularly with respect to the organization of the cerebral cortex. Therefore, in order to understand some aspects of human visual function, we need to study non-human primate brains. Which species is the most appropriate model? Macaque monkeys, the most widely used non-human primates, are not an optimal choice in many practical respects. For example, much of the macaque cerebral cortex is buried within sulci, and is therefore inaccessible to many imaging techniques, and the postnatal development and lifespan of macaques are prohibitively long for many studies of brain maturation, plasticity, and aging. In these and several other respects the marmoset, a small New World monkey, represents a more appropriate choice. Here we review the visual pathways of the marmoset, highlighting recent work that brings these advantages into focus, and identify where additional work needs to be done to link marmoset brain organization to that of macaques and humans. We will argue that the marmoset monkey provides a good subject for studies of a complex visual system, which will likely allow an important bridge linking experiments in animal models to humans. PMID:25152716

  20. Performance of the marmoset monkey on computerized tasks of attention and working memory.

    PubMed

    Spinelli, Simona; Pennanen, Luis; Dettling, Andrea C; Feldon, Joram; Higgins, Guy A; Pryce, Christopher R

    2004-04-01

    The CAmbridge Neuropsychological Test Automated Battery (CANTAB) is a computerised battery of neuropsychological tests presented as stimuli on a touch-sensitive computer screen that has been used to assess a wide range of cognitive functions in neuropsychiatric patients, healthy volunteers, and species of non-human primate, primarily the rhesus macaque. The common marmoset is a small-bodied, tractable simian primate that breeds well under laboratory conditions. This primate has been quite extensively studied in terms of its abilities and limitations with respect to appetitive cognitive conditioning. However, the CANTAB versions of sustained/divided attention and working memory tasks have to-date not been studied in the marmoset. Here we describe adult marmoset performance on the CANTAB five-choice serial reaction time task, a delayed match-to-position task, and a task derived from the CANTAB visuo-spatial paired associates learning task that constituted two, concurrent delayed match-to-position tasks. The acquisition and stable longitudinal performance of these tasks provide strong evidence that the marmoset, in addition to the macaque, can be the species of choice for CANTAB-based drug and lesion studies of cognitive function, using tasks similar to those deployed in the study of human cognition and diagnosis of neuropsychiatric disorders.

  1. An operant conditioning method for studying auditory behaviors in marmoset monkeys.

    PubMed

    Remington, Evan D; Osmanski, Michael S; Wang, Xiaoqin

    2012-01-01

    The common marmoset (Callithrix jacchus) is a small New World primate that has increasingly been used as a non-human model in the fields of sensory, motor, and cognitive neuroscience. However, little knowledge exists regarding behavioral methods in this species. Developing an understanding of the neural basis of perception and cognition in an animal model requires measurement of both brain activity and behavior. Here we describe an operant conditioning behavioral training method developed to allow controlled psychoacoustic measurements in marmosets. We demonstrate that marmosets can be trained to consistently perform a Go/No-Go auditory task in which a subject licks at a feeding tube when it detects a sound. Correct responses result in delivery of a food reward. Crucially, this operant conditioning task generates little body movement and is well suited for pairing behavior with single-unit electrophysiology. Successful implementation of an operant conditioning behavior opens the door to a wide range of new studies in the field of auditory neuroscience using the marmoset as a model system.

  2. Ondansetron and arecoline prevent scopolamine-induced cognitive deficits in the marmoset.

    PubMed

    Carey, G J; Costall, B; Domeney, A M; Gerrard, P A; Jones, D N; Naylor, R J; Tyers, M B

    1992-05-01

    The cognitive-enhancing potential of the 5-hydroxytryptamine (5-HT) selective 5-HT3 receptor antagonist, ondansetron, was investigated in a model of cognitive impairment induced by the muscarinic receptor antagonist, scopolamine. For this purpose, marmosets were trained in an object discrimination task utilizing the Wisconsin General Test Apparatus. Administration of scopolamine (0.01-0.04 mg/kg, SC) caused a dose-dependent impairment in the acquisition of the object discrimination task in that marmosets required more trials to reach criterion, made more errors, and took longer to choose the objects. Administration of arecoline (0.06-0.1 mg/kg, SC) or 1,2,3,9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazol- 1-yl)methyl]-4H-carbazol-4-one,HCl.2H2O (ondansetron) (0.1-1 micrograms/kg, SC) prevented the scopolamine-induced impairment in task acquisition in that the performance of marmosets was indistinguishable from that of saline-treated animals and was significantly better than that following scopolamine/saline. From these studies, we conclude that ondansetron prevents impairment in the cognitive performance of marmosets induced by administration of scopolamine.

  3. Early development of turn-taking with parents shapes vocal acoustics in infant marmoset monkeys

    PubMed Central

    Takahashi, Daniel Y.; Fenley, Alicia R.; Ghazanfar, Asif A.

    2016-01-01

    In humans, vocal turn-taking is a ubiquitous form of social interaction. It is a communication system that exhibits the properties of a dynamical system: two individuals become coupled to each other via acoustic exchanges and mutually affect each other. Human turn-taking develops during the first year of life. We investigated the development of vocal turn-taking in infant marmoset monkeys, a New World species whose adult vocal behaviour exhibits the same universal features of human turn-taking. We find that marmoset infants undergo the same trajectory of change for vocal turn-taking as humans, and do so during the same life-history stage. Our data show that turn-taking by marmoset infants depends on the development of self-monitoring, and that contingent parental calls elicit more mature-sounding calls from infants. As in humans, there was no evidence that parental feedback affects the rate of turn-taking maturation. We conclude that vocal turn-taking by marmoset monkeys and humans is an instance of convergent evolution, possibly as a result of pressures on both species to adopt a cooperative breeding strategy and increase volubility. PMID:27069047

  4. Marmoset: A programming project assignment framework to improve the feedback cycle for students, faculty and researchers

    NASA Astrophysics Data System (ADS)

    Spacco, Jaime W.

    We developed Marmoset, a system that improves the feedback cycle on programming assignments for students, faculty and researchers alike. Using automation, Marmoset substantially lowers the burden on faculty for grading programming assignments, allowing faculty to give students more rapid feedback on their assignments. To further improve the feedback cycle, Marmoset provides students with limited access to the results of the instructor's private test cases before the submission deadline using a novel token-based incentive system. This both encourages students to start their work early and to think critically about their work. Because students submit early, instructors can monitor all students' progress on test cases and identify where in projects students are having problems in order to update the project requirements in a timely fashion and make the best use of time in lectures, discussion sections, and office hours. To study in more detail the development process of students, Marmoset can be configured to transparently capture snapshots to a central repository every-time students save their files. These detailed development histories offer a unique, detailed perspective of each student's progress on a programming assignment, from the first line of code written and saved all the way through the final edit before the final submission. This type of data has proved extremely valuable for many uses, such as mining new bug patterns and evaluating existing bug-finding tools.

  5. The Marmoset as a Model of Aging and Age-Related Diseases

    PubMed Central

    Tardif, Suzette D.; Mansfield, Keith G.; Ratnam, Rama; Ross, Corinna N.; Ziegler, Toni E.

    2013-01-01

    The common marmoset (Callithrix jacchus) is poised to become a standard nonhuman primate aging model. With an average lifespan of 5 to 7 years and a maximum lifespan of 16.5 years, marmosets are the shortest-lived anthropoid primates. They display age-related changes in pathologies that mirror those seen in humans, such as cancer, amyloidosis, diabetes, and chronic renal disease. They also display predictable age-related differences in lean mass, calf circumference, circulating albumin, hemoglobin, and hematocrit. Features of spontaneous sensory and neurodegenerative change—for example, reduced neurogenesis, β-amyloid deposition in the cerebral cortex, loss of calbindin D28k binding, and evidence of presbycusis—appear between the ages of 7 and 10 years. Variation among colonies in the age at which neurodegenerative change occurs suggests the interesting possibility that marmosets could be specifically managed to produce earlier versus later occurrence of degenerative conditions associated with differing rates of damage accumulation. In addition to the established value of the marmoset as a model of age-related neurodegenerative change, this primate can serve as a model of the integrated effects of aging and obesity on metabolic dysfunction, as it displays evidence of such dysfunction associated with high body weight as early as 6 to 8 years of age. PMID:21411858

  6. Touchscreen assays of learning, response inhibition, and motivation in the marmoset (Callithrix jacchus).

    PubMed

    Kangas, Brian D; Bergman, Jack; Coyle, Joseph T

    2016-05-01

    Recent developments in precision gene editing have led to the emergence of the marmoset as an experimental subject of considerable interest and translational value. A better understanding of behavioral phenotypes of the common marmoset will inform the extent to which forthcoming transgenic mutants are cognitively intact. Therefore, additional information regarding their learning, inhibitory control, and motivational abilities is needed. The present studies used touchscreen-based repeated acquisition and discrimination reversal tasks to examine basic dimensions of learning and response inhibition. Marmosets were trained daily to respond to one of the two simultaneously presented novel stimuli. Subjects learned to discriminate the two stimuli (acquisition) and, subsequently, with the contingencies switched (reversal). In addition, progressive ratio performance was used to measure the effort expended to obtain a highly palatable reinforcer varying in magnitude and, thereby, provide an index of relative motivational value. Results indicate that rates of both acquisition and reversal of novel discriminations increased across successive sessions, but that rate of reversal learning remained slower than acquisition learning, i.e., more trials were needed for mastery. A positive correlation was observed between progressive ratio break point and reinforcement magnitude. These results closely replicate previous findings with squirrel monkeys, thus providing evidence of similarity in learning processes across nonhuman primate species. Moreover, these data provide key information about the normative phenotype of wild-type marmosets using three relevant behavioral endpoints. PMID:26846231

  7. T and B lymphocytes in the marmoset: a natural haemopoietic chimera.

    PubMed

    Niblack, G D; Gengozian, N

    1976-03-01

    The thymus-derived (T) lymphocyte and bone marrow-derived (B) lymphocyte populations of the marmoset were characterized using specific cell surface markers Approximately 85% of the thymocyates formed rosettes with neuraminidase-treated sheep erythrocytes (En). The percentage (approximately 69%) of peripheral blood lymphocytes (PBL) forming rosettes with En was the same as that which stained with fluorescently labelled goat anti-marmoset thymocyte serum (ATS). These two assays identified the same cell population since treatment of cells with ATS and complement resulted in a concomitant decrease in En rosette formation. Marmoset PBL also formed rosettes with human erythrocytes sensitized with antibody and complement (HEAC); since the percentage (approximately 20%) HEAC rosette was the same as that of cells stained with fluorescently labelled goat anti-marmoset IgG, these cells were considered to be B cells. A small percentage of cells (approximately 1-5%) possessed both types of receptors. The mean percentages of T and B cells present in PBL of single-born, presumably non-chimeric animals, were the same as that of iso-sexual and heterosexual chimeras. PMID:820498

  8. Serum matrix metalloproteinase 9 (MMP9) as a biochemical marker for wasting marmoset syndrome.

    PubMed

    Yoshimoto, Takuro; Niimi, Kimie; Takahashi, Eiki

    2016-06-01

    Use of the common marmoset (Callithrix jacchus) as a non-human primate experimental animal has increased in recent years. Although wasting marmoset syndrome (WMS) is one of the biggest problems in captive marmoset colonies, the molecular mechanisms, biochemical markers for accurate diagnosis and a reliable treatment remain unknown. In this study, as a first step to finding biochemical marker(s) for the accurate diagnosis of WMS, we conducted blood cell counts, including hematocrit, hemoglobin and platelets, and examined serum chemistry values, including albumin, calcium and levels of serum matrix metalloproteinase 9 (MMP9), using a colony of marmosets with and without weight loss. MMP9 is thought to be an enzyme responsible for the degradation of extracellular matrix components and participates in the pathogenesis of inflammatory conditions, such as human and murine inflammatory bowel disease, which, like WMS, are characterized histologically by inflammatory cell infiltrations in the intestines. The values of hematocrit and hemoglobin and levels of serum albumin and calcium in the WMS group were significantly decreased versus the control group. The platelet values and serum MMP9 concentrations were increased significantly in the WMS group compared with the control group. MMP9 could be a new and useful marker for the diagnosis of WMS in addition to hematocrit, hemoglobin, serum albumin and calcium. Our results also indicate that MMP9 could be a useful molecular candidate for treatment.

  9. T and B lymphocytes in the marmoset: a natural haemopoietic chimera.

    PubMed Central

    Niblack, G D; Gengozian, N

    1976-01-01

    The thymus-derived (T) lymphocyte and bone marrow-derived (B) lymphocyte populations of the marmoset were characterized using specific cell surface markers Approximately 85% of the thymocyates formed rosettes with neuraminidase-treated sheep erythrocytes (En). The percentage (approximately 69%) of peripheral blood lymphocytes (PBL) forming rosettes with En was the same as that which stained with fluorescently labelled goat anti-marmoset thymocyte serum (ATS). These two assays identified the same cell population since treatment of cells with ATS and complement resulted in a concomitant decrease in En rosette formation. Marmoset PBL also formed rosettes with human erythrocytes sensitized with antibody and complement (HEAC); since the percentage (approximately 20%) HEAC rosette was the same as that of cells stained with fluorescently labelled goat anti-marmoset IgG, these cells were considered to be B cells. A small percentage of cells (approximately 1-5%) possessed both types of receptors. The mean percentages of T and B cells present in PBL of single-born, presumably non-chimeric animals, were the same as that of iso-sexual and heterosexual chimeras. PMID:820498

  10. Establishment of lethal inhalational infection with Francisella tularensis (tularaemia) in the common marmoset (Callithrix jacchus).

    PubMed

    Nelson, Michelle; Lever, Mark S; Savage, Victoria L; Salguero, Francisco Javier; Pearce, Peter C; Stevens, Daniel J; Simpson, Andrew J H

    2009-04-01

    Susceptibility and lethality studies of inhalational tularaemia were undertaken using the common marmoset (Callithrix jacchus) to determine its suitability as a non-human primate model. Pairs of marmosets were exposed to varying challenge doses of Francisella tularensis by the airborne route and monitored for up to 14 days postchallenge (p.c.). Lethal infection was achieved following a retained dose of less than 10 bacterial colony-forming units (CFU). However, precise LD(50) determination was not possible. The model was characterized using a target challenge dose of approximately 100 CFU. Increased core body temperature was the first indicator of disease, at approximately 2.5 days p.c. Overt clinical signs were first observed 12-18 h after the temperature increase. Significantly decreased activity was observed after approximately 3 days. All animals succumbed to infection between 4.5 and 7 days p.c. At postmortem examination, gross pathology was evident in the liver, spleen and lungs of all animals and high bacterial numbers were detected in all the organs assessed. Bacteraemia was demonstrated in all animals postmortem. Histopathological observations included severe suppurative bronchopneumonia, severe multifocal pyogranulomatous hepatitis, splenitis and lymphadenitis. Tularaemia disease progression in the common marmoset therefore appears to be consistent with the disease seen in humans and other animal models. The common marmoset may therefore be considered a suitable model for further studies of inhalational tularaemia.

  11. Can vocal conditioning trigger a semiotic ratchet in marmosets?

    PubMed

    Turesson, Hjalmar K; Ribeiro, Sidarta

    2015-01-01

    The complexity of human communication has often been taken as evidence that our language reflects a true evolutionary leap, bearing little resemblance to any other animal communication system. The putative uniqueness of the human language poses serious evolutionary and ethological challenges to a rational explanation of human communication. Here we review ethological, anatomical, molecular, and computational results across several species to set boundaries for these challenges. Results from animal behavior, cognitive psychology, neurobiology, and semiotics indicate that human language shares multiple features with other primate communication systems, such as specialized brain circuits for sensorimotor processing, the capability for indexical (pointing) and symbolic (referential) signaling, the importance of shared intentionality for associative learning, affective conditioning and parental scaffolding of vocal production. The most substantial differences lie in the higher human capacity for symbolic compositionality, fast vertical transmission of new symbols across generations, and irreversible accumulation of novel adaptive behaviors (cultural ratchet). We hypothesize that increasingly-complex vocal conditioning of an appropriate animal model may be sufficient to trigger a semiotic ratchet, evidenced by progressive sign complexification, as spontaneous contact calls become indexes, then symbols and finally arguments (strings of symbols). To test this hypothesis, we outline a series of conditioning experiments in the common marmoset (Callithrix jacchus). The experiments are designed to probe the limits of vocal communication in a prosocial, highly vocal primate 35 million years far from the human lineage, so as to shed light on the mechanisms of semiotic complexification and cultural transmission, and serve as a naturalistic behavioral setting for the investigation of language disorders.

  12. Can vocal conditioning trigger a semiotic ratchet in marmosets?

    PubMed Central

    Turesson, Hjalmar K.; Ribeiro, Sidarta

    2015-01-01

    The complexity of human communication has often been taken as evidence that our language reflects a true evolutionary leap, bearing little resemblance to any other animal communication system. The putative uniqueness of the human language poses serious evolutionary and ethological challenges to a rational explanation of human communication. Here we review ethological, anatomical, molecular, and computational results across several species to set boundaries for these challenges. Results from animal behavior, cognitive psychology, neurobiology, and semiotics indicate that human language shares multiple features with other primate communication systems, such as specialized brain circuits for sensorimotor processing, the capability for indexical (pointing) and symbolic (referential) signaling, the importance of shared intentionality for associative learning, affective conditioning and parental scaffolding of vocal production. The most substantial differences lie in the higher human capacity for symbolic compositionality, fast vertical transmission of new symbols across generations, and irreversible accumulation of novel adaptive behaviors (cultural ratchet). We hypothesize that increasingly-complex vocal conditioning of an appropriate animal model may be sufficient to trigger a semiotic ratchet, evidenced by progressive sign complexification, as spontaneous contact calls become indexes, then symbols and finally arguments (strings of symbols). To test this hypothesis, we outline a series of conditioning experiments in the common marmoset (Callithrix jacchus). The experiments are designed to probe the limits of vocal communication in a prosocial, highly vocal primate 35 million years far from the human lineage, so as to shed light on the mechanisms of semiotic complexification and cultural transmission, and serve as a naturalistic behavioral setting for the investigation of language disorders. PMID:26500583

  13. Finite element analysis of performance in the skulls of marmosets and tamarins

    PubMed Central

    Dumont, Elizabeth R; Davis, Julian L; Grosse, Ian R; Burrows, Anne M

    2011-01-01

    Reliance on plant exudates is a relatively rare dietary specialization among mammals. One well-studied example of closely related exudate feeders is the New World marmosets and tamarins. Whereas marmosets actively gouge tree bark with their incisors to stimulate the flow of sap, tamarins are opportunistic exudate feeders that do not gouge bark. Several studies of the dentaries and jaw adductors indicate that marmosets exhibit specializations for increased gape at the expense of bite force. Few studies, however, have looked to the cranium of marmosets for evidence of functional specializations. Using 3D finite element models of the marmoset Callithrix jacchus and the tamarin Saguinus fuscicollis, we investigated the performance of the cranium under loading regimes that mimicked unilateral molar biting and bark-gouging. We investigated three measures of performance: the efficiency with which muscle force is transferred to bite force, the extent to which the models are stressed (a predictor of failure), and the work expended by muscles as they deform the skull (total strain energy). We found that during molar biting the two models exhibited similar levels of performance, though the Saguinus model had slightly higher mechanical efficiency, a slightly lower state of stress, and expended more energy on deformation. In contrast, under the bark-gouging load, Callithrix exhibited much higher mechanical efficiency than Saguinas, but did so at the expense of more work and higher levels of von Mises stress. This analysis illustrates that differences in the shapes of the skulls of Callithrix and Saguinus confer differences in performance. Whether these aspects of performance are targets of selection awaits broader comparative analyses. PMID:20572898

  14. Survey and Experimental Infection of Enteropathogenic Escherichia coli in Common Marmosets (Callithrix jacchus).

    PubMed

    Hayashimoto, Nobuhito; Inoue, Takashi; Morita, Hanako; Yasuda, Masahiko; Ueno, Masami; Kawai, Kenji; Itoh, Toshio

    2016-01-01

    Common marmosets (Callithrix jacchus) are frequently used for biomedical research but can be afflicted with diarrhea-a serious and potentially lethal health problem. Enteropathogenic Escherichia coli (EPEC) is thought to be the causative pathogen of hemorrhagic typhlocolitis in common marmosets, but the actual incidence of the disease and the relationship between EPEC and hematochezia are unknown. This study investigated the prevalence of EPEC infection in common marmosets and the association between EPEC and hematochezia. A total of 230 stool or rectal swab samples were collected from 230 common marmosets (98 clinically healthy, 85 diarrhea, and 47 bloody stool samples) and tested by culture-based detection and PCR amplification of VT1, VT2, LT, ST, eae, and bfp genes. Healthy animals were divided into three groups (n = 4 each for high and low concentration groups and n = 2 as negative control), and those in the experimental groups were perorally inoculated with a 2-ml of suspension of EPEC R811 strain adjusted to 5 × 108 (high concentration) and 5 × 104 (low concentration) CFU/ ml. Two animals in each group were examined 3 and 14 days post-inoculation (DPI). EPEC was detected in 10 of 98 clinically healthy samples (10.2%), 17 of 85 diarrhea samples (20%), and all 47 bloody stool samples (100%), with a significant difference detected between presence of EPEC and sample status (P < 0.01). Acute hematochezia was observed in all animals of the high-concentration group but not in other groups at 1 or 2 DPI. A histopathological examination revealed the attachment of gram-negative bacilli to epithelial apical membranes and desquamated epithelial cells in the cecum of animals in the high-concentration group at 3 DPI. These findings suggest that EPEC is a causative agent of hemorrhagic typhlocolitis in common marmosets. PMID:27501144

  15. Birth of Healthy Offspring following ICSI in In Vitro-Matured Common Marmoset (Callithrix jacchus) Oocytes

    PubMed Central

    Takahashi, Tsukasa; Hanazawa, Kisaburo; Inoue, Takashi; Sato, Kenya; Sedohara, Ayako; Okahara, Junko; Suemizu, Hiroshi; Yagihashi, Chie; Yamamoto, Masafumi; Eto, Tomoo; Konno, Yusuke; Okano, Hideyuki; Suematsu, Makoto; Sasaki, Erika

    2014-01-01

    Intracytoplasmic sperm injection (ICSI), an important method used to treat male subfertility, is applied in the transgenic technology of sperm-mediated gene transfer. However, no study has described successful generation of offspring using ICSI in the common marmoset, a small non-human primate used as a model for biomedical translational research. In this study, we investigated blastocyst development and the subsequent live offspring stages of marmoset oocytes matured in vitro and fertilized by ICSI. To investigate the optimal timing of performing ICSI, corrected immature oocytes were matured in vitro and ICSI was performed at various time points (1–2 h, 2–4 h, 4–6 h, 6–8 h, and 8–10 h after extrusion of the first polar body (PB)). Matured oocytes were then divided randomly into two groups: one was used for in vitro fertilization (IVF) and the other for ICSI. To investigate in vivo development of embryos followed by ICSI, 6-cell- to 8-cell-stage embryos and blastocysts were nonsurgically transferred into recipient marmosets. Although no significant differences were observed in the fertilization rate of blastocysts among ICSI timing after the first PB extrusion, the blastocyst rate at 1–2 h was lowest among groups at 2–4 h, 4–6 h, 6–8 h, and 8–10 h. Comparing ICSI to IVF, the fertilization rates obtained in ICSI were higher than in IVF (p>0.05). No significant difference was noted in the cleaved blastocyst rate between ICSI and IVF. Following the transfer of 37 ICSI blastocysts, 4 of 20 recipients became pregnant, while with the transfer of 21 6-cell- to 8-cell-stage ICSI embryos, 3 of 8 recipients became pregnant. Four healthy offspring were produced and grew normally. These are the first marmoset offspring produced by ICSI, making it an effective fertilization method for marmosets. PMID:24751978

  16. Differential contribution of dietary fat and monosaccharide to metabolic syndrome in the common marmoset (Callithrix jacchus)

    PubMed Central

    Wachtman, Lynn M.; Kramer, Joshua A.; Miller, Andrew D.; Hachey, Audra; Curran, Elizabeth; Mansfield, Keith G.

    2011-01-01

    There is a critical need for animal models to study aspects type 2 diabetes mellitus pathogenesis and prevention. While the rhesus macaque is such an established model, the common marmoset has added benefits including reduced zoonotic risks, shorter life span, and a predisposition to birth twins demonstrating chimerism. The marmoset as a model organism for the study of metabolic syndrome has not been fully evaluated. Marmosets fed high-fat or glucose-enriched diets were followed longitudinally to observe effects on morphometric and metabolic measures. Effects on pancreatic histomorphometry and vascular pathology were examined terminally. The glucose–enriched diet group developed an obese phenotype and a prolonged hyperglycemic state evidenced by a rapid and persistent increase in mean glycosylated hemoglobin (HgbA1c) observed as early as week 16. In contrast, marmosets fed a high-fat diet did not maintain an obese phenotype and demonstrated a delayed increase in HgbA1c that did not reach statistical significance until week 40. Consumption of either diet resulted in profound pancreatic islet hyperplasia suggesting a compensation for increased insulin requirements. Although the high fat diet group developed atherosclerosis of increased severity, the presence of lesions correlated with glucose intolerance only in the glucose-enriched diet group. The altered timing of glucose dysregulation, differential contribution to obesity, and variation in vascular pathology suggests mechanisms of effect specific to dietary nutrient content. Feeding nutritionally modified diets to common marmosets recapitulates aspects of metabolic disease and represents a model that may prove instrumental to elucidating the contribution of nutrient excess to disease development. PMID:21164504

  17. Survey and Experimental Infection of Enteropathogenic Escherichia coli in Common Marmosets (Callithrix jacchus)

    PubMed Central

    Hayashimoto, Nobuhito; Inoue, Takashi; Morita, Hanako; Yasuda, Masahiko; Ueno, Masami; Kawai, Kenji; Itoh, Toshio

    2016-01-01

    Common marmosets (Callithrix jacchus) are frequently used for biomedical research but can be afflicted with diarrhea—a serious and potentially lethal health problem. Enteropathogenic Escherichia coli (EPEC) is thought to be the causative pathogen of hemorrhagic typhlocolitis in common marmosets, but the actual incidence of the disease and the relationship between EPEC and hematochezia are unknown. This study investigated the prevalence of EPEC infection in common marmosets and the association between EPEC and hematochezia. A total of 230 stool or rectal swab samples were collected from 230 common marmosets (98 clinically healthy, 85 diarrhea, and 47 bloody stool samples) and tested by culture-based detection and PCR amplification of VT1, VT2, LT, ST, eae, and bfp genes. Healthy animals were divided into three groups (n = 4 each for high and low concentration groups and n = 2 as negative control), and those in the experimental groups were perorally inoculated with a 2-ml of suspension of EPEC R811 strain adjusted to 5 × 108 (high concentration) and 5 × 104 (low concentration) CFU/ ml. Two animals in each group were examined 3 and 14 days post-inoculation (DPI). EPEC was detected in 10 of 98 clinically healthy samples (10.2%), 17 of 85 diarrhea samples (20%), and all 47 bloody stool samples (100%), with a significant difference detected between presence of EPEC and sample status (P < 0.01). Acute hematochezia was observed in all animals of the high-concentration group but not in other groups at 1 or 2 DPI. A histopathological examination revealed the attachment of gram-negative bacilli to epithelial apical membranes and desquamated epithelial cells in the cecum of animals in the high-concentration group at 3 DPI. These findings suggest that EPEC is a causative agent of hemorrhagic typhlocolitis in common marmosets. PMID:27501144

  18. Neurofilament proteins are preferentially expressed in descending output neurons of the cat the superior colliculus: a study using SMI-32.

    PubMed

    Fuentes-Santamaria, V; Stein, B E; McHaffie, J G

    2006-01-01

    Physiological studies indicate that the output neurons in the multisensory (i.e. intermediate and deep) laminae of the cat superior colliculus receive converging information from widespread regions of the neuraxis, integrate this information, and then relay the product to regions of the brainstem involved in the control of head and eye movements. Yet, an understanding of the neuroanatomy of these converging afferents has been hampered because many terminals contact distal dendrites that are difficult to label with the neurochemical markers generally used to visualize superior colliculus output neurons. Here we show that the SMI-32 antibody, directed at the non-phosphorylated epitopes of high molecular weight neurofilament proteins, is an effective marker for these superior colliculus output neurons. It is also one that can label their distal dendrites. Superior colliculus sections processed for SMI-32 revealed numerous labeled neurons with varying morphologies within the deep laminae. In contrast, few labeled neurons were observed in the superficial laminae. Neurons with large somata in the lateral aspects of the deep superior colliculus were particularly well labeled, and many of their secondary and tertiary dendrites were clearly visible. Injections of the fluorescent biotinylated dextran amine into the pontine reticular formation revealed that approximately 80% of the SMI-32 immunostained neurons also contained retrogradely transported biotinylated dextran amine, indicating that SMI-32 is a common cytoskeletal component expressed in descending output neurons. Superior colliculus output neurons also are known to express the calcium-binding protein parvalbumin, and many SMI-32 immunostained neurons also proved to be parvalbumin immunostained. These studies suggest that SMI-32 can serve as a useful immunohistochemical marker for detailing the somatic and dendritic morphology of superior colliculus output neurons and for facilitating evaluations of their input

  19. Oxytocin facilitates fidelity in well-established marmoset pairs by reducing sociosexual behavior toward opposite-sex strangers.

    PubMed

    Cavanaugh, Jon; Mustoe, Aaryn C; Taylor, Jack H; French, Jeffrey A

    2014-11-01

    Behavioral strategies that facilitate the maintenance of social bonds are critical for the preservation of high-quality social relationships. Central oxytocin (OT) activity modulates the behavioral features of socially monogamous relationships in a number of mammalian species (including marmoset monkeys), and plays a vital role in the behavioral maintenance of long-term social relationships. Two distinct variants of OT have been identified in some New World primates (including marmosets; Lee et al., 2011). The marmoset variant of the oxytocin ligand (Pro(8)-OT) is structurally distinct from the consensus mammalian variant of the oxytocin ligand (Leu(8)-OT), due to a proline substitution at the 8th amino-acid position. The goal of the present study was to determine if treating marmosets with Pro(8)-OT, relative to treatments with Leu(8)-OT, control saline, or an OT antagonist, had modulatory effects on the behavioral maintenance of long-term social relationships in marmosets. Treatment with the Pro(8) variant, but not the Leu(8) variant, of OT facilitated fidelity with a long-term partner by reducing time spent in close proximity with an opposite-sex stranger. However, this facilitative effect of Pro(8)-OT on proximity behavior manifested itself differently in male and female marmosets, such that females preferred to interact socially with their partner rather than a stranger when treated with Pro(8)-OT, while males spent less time in close proximity with both their partner and a stranger when treated with Pro(8)-OT. Furthermore, treatment with Pro(8)-OT, but not Leu(8)-OT, significantly delayed the expression of sexual solicitation behavior toward an opposite-sex stranger in both male and female marmosets, but had no effect on sociosexual behavior directed toward a long-term partner. These results suggest that the OT system is highly involved in reducing fidelity-threatening behaviors in well-established marmoset pairs, and that the effects were only produced by

  20. Inferior mirages: an improved model.

    PubMed

    Young, Andrew T

    2015-02-01

    A quantitative model of the inferior mirage is presented, based on a realistic temperature profile in the convective boundary layer, using Monin-Obukhov similarity theory. The top of the inverted image is determined by the logarithmic part of the profile; the bottom is the apparent horizon, which depends on optical obstruction by roughness elements. These effects of surface roughness are included in the model, which is illustrated with a simulation. The vertical magnification varies throughout the mirage, becoming infinite at Minnaert's ill-named "vanishing line"-which makes green flashes apparent to the naked eye. PMID:25967823

  1. Marmoset cytochrome P450 2J2 mainly expressed in small intestines and livers effectively metabolizes human P450 2J2 probe substrates, astemizole and terfenadine.

    PubMed

    Uehara, Shotaro; Uno, Yasuhiro; Inoue, Takashi; Okamoto, Eriko; Sasaki, Erika; Yamazaki, Hiroshi

    2016-11-01

    1. Common marmoset (Callithrix jacchus), a New World Monkey, has potential to be a useful animal model in preclinical studies. However, drug metabolizing properties have not been fully understood due to insufficient information on cytochrome P450 (P450), major drug metabolizing enzymes. 2. Marmoset P450 2J2 cDNA was isolated from marmoset livers. The deduced amino acid sequence showed a high-sequence identity (91%) with cynomolgus monkey and human P450 2J2 enzymes. A phylogenetic tree revealed that marmoset P450 2J2 was evolutionarily closer to cynomolgus monkey and human P450 2J2 enzymes, than P450 2J forms in pigs, rabbits, rats or mice. 3. Marmoset P450 2J2 mRNA was abundantly expressed in the small intestine and liver, and to a lesser extent in the brain, lung and kidney. Immunoblot analysis also showed expression of marmoset P450 2J2 protein in the small intestine and liver. 4. Enzyme assays using marmoset P450 2J2 protein heterologously expressed in Escherichia coli indicated that marmoset P450 2J2 effectively catalyzed astemizole O-demethylation and terfenadine t-butyl hydroxylation, similar to human and cynomolgus monkey P450 2J2 enzymes. 5. These results suggest the functional characteristics of P450 2J2 enzymes are similar among marmosets, cynomolgus monkeys and humans.

  2. Marmoset cytochrome P450 2J2 mainly expressed in small intestines and livers effectively metabolizes human P450 2J2 probe substrates, astemizole and terfenadine.

    PubMed

    Uehara, Shotaro; Uno, Yasuhiro; Inoue, Takashi; Okamoto, Eriko; Sasaki, Erika; Yamazaki, Hiroshi

    2016-11-01

    1. Common marmoset (Callithrix jacchus), a New World Monkey, has potential to be a useful animal model in preclinical studies. However, drug metabolizing properties have not been fully understood due to insufficient information on cytochrome P450 (P450), major drug metabolizing enzymes. 2. Marmoset P450 2J2 cDNA was isolated from marmoset livers. The deduced amino acid sequence showed a high-sequence identity (91%) with cynomolgus monkey and human P450 2J2 enzymes. A phylogenetic tree revealed that marmoset P450 2J2 was evolutionarily closer to cynomolgus monkey and human P450 2J2 enzymes, than P450 2J forms in pigs, rabbits, rats or mice. 3. Marmoset P450 2J2 mRNA was abundantly expressed in the small intestine and liver, and to a lesser extent in the brain, lung and kidney. Immunoblot analysis also showed expression of marmoset P450 2J2 protein in the small intestine and liver. 4. Enzyme assays using marmoset P450 2J2 protein heterologously expressed in Escherichia coli indicated that marmoset P450 2J2 effectively catalyzed astemizole O-demethylation and terfenadine t-butyl hydroxylation, similar to human and cynomolgus monkey P450 2J2 enzymes. 5. These results suggest the functional characteristics of P450 2J2 enzymes are similar among marmosets, cynomolgus monkeys and humans. PMID:26899760

  3. Maturation, fertilization, and development of marmoset monkey oocytes in vitro.

    PubMed

    Gilchrist, R B; Nayudu, P L; Hodges, J K

    1997-01-01

    This study was conducted to investigate 1) the capacity of in vitro-matured (IVM) marmoset oocytes to be fertilized and to support embryonic development in vitro and 2) oocyte meiotic maturation in relation to in vivo FSH administration, follicle size, and oocyte-cumulus cell status. Pairs of ovaries were collected on Day 4 of the follicular phase from adult females receiving either 1) human FSH (3 IU; n = 5) or 2) control (saline; n = 5) daily for 4 days. Antral follicles were excised from ovaries and separated into classes according to size: class 1 (660-840 microm), class 2 (> 840-1000 microm), class 3 (> 1000-1400 microm), and class 4 (> 1400 microm). A total of 823 partially naked and cumulus-enclosed oocytes (CEOs) were released from follicles and cultured in vitro. Cumulus cells remaining after 22 h were removed, metaphase II (MII) oocytes were inseminated with epididymal sperm, and resulting embryos were cultured until developmental arrest. Fluorescence microscopy was used to assess oocyte meiotic and embryo developmental progression. Oocyte germinal vesicle breakdown (GVB)- and MII-competencies increased significantly with follicular size (p < 0.01 and p < 0.0001, respectively), although they were independent of oocyte-cumulus cell associations. After 24 and 32 h in vitro, 69% and 93%, respectively, of CEOs with MII competence had completed meiotic maturation, and the rate of nuclear maturation increased progressively with follicle size (p < 0.01) and with the association of cumulus cells (p < 0.01). In vivo FSH priming slightly improved oocyte GVB- and MII-competencies (p < 0.01 and p < 0.05, respectively) and decreased the time required to achieve MII (p < 0.01). IVM oocytes from all follicle sizes fertilized (78-92%) in vitro, with 27% developing to morula- and 4% to blastocyst-stage embryos. This study demonstrates for the first time that IVM New World primate oocytes are able to support advanced preimplantation embryonic development in vitro. Oocyte

  4. Orienting responses and vocalizations produced by microstimulation in the superior colliculus of the echolocating bat, Eptesicus fuscus.

    PubMed

    Valentine, Doreen E; Sinha, Shiva R; Moss, Cynthia F

    2002-03-01

    An echolocating bat actively controls the spatial acoustic information that drives its behavior by directing its head and ears and by modulating the spectro-temporal structure of its outgoing sonar emissions. The superior colliculus may function in the coordination of these orienting components of the bat's echolocation system. To test this hypothesis, chemical and electrical microstimulation experiments were carried out in the superior colliculus of the echolocating bat, Eptesicus fuscus, a species that uses frequency modulated sonar signals. Microstimulation elicited pinna and head movements, similar to those reported in other vertebrate species, and the direction of the evoked behaviors corresponded to the site of stimulation, yielding a map of orienting movements in the superior colliculus. Microstimulation of the bat superior colliculus also elicited sonar vocalizations, a motor behavior specific to the bat's acoustic orientation by echolocation. Electrical stimulation of the adjacent periaqueductal gray, shown to be involved in vocal production in other mammalian species, elicited vocal signals resembling acoustic communication calls of E. fuscus. The control of vocal signals in the bat is an integral part of its acoustic orienting system, and our findings suggest that the superior colliculus supports diverse and species-relevant sensorimotor behaviors, including those used for echolocation.

  5. INTERDEPENDENT SUPERIORITY AND INFERIORITY FEELINGS

    PubMed Central

    Ingham, Harrington V.

    1949-01-01

    It is postulated that in neurotic persons who have unrealistic feelings of superiority and inferiority the two are interdependent. This is a departure from the concept of previous observers that either one or the other is primary and its opposite is overcompensation. The author postulates considerable parallelism, with equal importance for each. He submits that the neurotic person forms two logic-resistant compartments for the two opposed self-estimates and that treatment which makes inroads of logic upon one compartment, simultaneously does so upon the other. Two examples are briefly reported. The neurotic benefits sought in exaggeration of capability are the same as those sought in insistence upon inferiority: Presumption of superiority at once bids for approbation and delivers the subject from the need to prove himself worthy of it in dreaded competition; exaggeration of incapability baits sympathy and makes competition unnecessary because failure is conceded. Some of the characteristics of abnormal self-estimates that distinguish them from normal are: Preoccupation with self, resistance to logical explanation of personality problems, inconsistency in reasons for beliefs in adequacy on the one hand and inadequacy on the other, unreality, rationalization of faults, and difficulty and vacillation in the selection of adequate goals. PMID:15390573

  6. Oxytocin modulates behavioral and physiological responses to a stressor in marmoset monkeys.

    PubMed

    Cavanaugh, Jon; Carp, Sarah B; Rock, Chelsea M; French, Jeffrey A

    2016-04-01

    Social isolation is a major source of stress and can lead to activation of the hypothalamic-pituitary-adrenal (HPA) axis. The presence of a close social partner can reduce the magnitude of the HPA-axis response during a stressor, a phenomenon known as social buffering. The oxytocin (OXT) system has been identified as one candidate for mediating social buffering due to its role in the facilitation of social bonding and the expression of prosocial behavior. The goal of the present study was to determine whether the OXT system contributes to social buffering of HPA-axis activity in response to stressor exposure in marmoset monkeys (Callithrix jacchus). Male and female marmosets experienced a standardized psychogenic stressor with and without their long-term mate under OXT-treatments (Pro(8)-OXT, Leu(8)-OXT, OXT antagonist, and saline); we assessed HPA-axis activity by measuring urinary cortisol across the stressor. We found that blocking, but not augmenting, the OXT system altered patterns of cortisol and proximity behavior in response to a stressor. We demonstrated that (1) the presence of a mate during a stressor significantly attenuated HPA-axis activity in female, but not male, marmosets; (2) male, but not female, marmosets treated with an OXT antagonist had significantly higher HPA-axis activity across the stressor than when they were treated with saline, suggesting that the OXT system may reduce the stressor-induced rise in cortisol levels; (3) male and female marmosets treated with an OXT antagonist spent significantly less time in close proximity to their mate during the first 30 min of the stressor than when they were treated with saline, suggesting that the OXT system may be important for the expression of partner-seeking behavior during a stressor. Thus, the OXT system and social context differentially influenced how the HPA-axis responded to a stressor in male and female marmosets, and may modulate HPA-axis activity by promoting the expression of proximity

  7. Defective response inhibition and collicular noradrenaline enrichment in mice with duplicated retinotopic map in the superior colliculus.

    PubMed

    Mathis, Chantal; Savier, Elise; Bott, Jean-Bastien; Clesse, Daniel; Bevins, Nicholas; Sage-Ciocca, Dominique; Geiger, Karin; Gillet, Anaïs; Laux-Biehlmann, Alexis; Goumon, Yannick; Lacaud, Adrien; Lelièvre, Vincent; Kelche, Christian; Cassel, Jean-Christophe; Pfrieger, Frank W; Reber, Michael

    2015-01-01

    The superior colliculus is a hub for multisensory integration necessary for visuo-spatial orientation, control of gaze movements and attention. The multiple functions of the superior colliculus have prompted hypotheses about its involvement in neuropsychiatric conditions, but to date, this topic has not been addressed experimentally. We describe experiments on genetically modified mice, the Isl2-EphA3 knock-in line, that show a well-characterized duplication of the retino-collicular and cortico-collicular axonal projections leading to hyperstimulation of the superior colliculus. To explore the functional impact of collicular hyperstimulation, we compared the performance of homozygous knock-in, heterozygous knock-in and wild-type mice in several behavioral tasks requiring collicular activity. The light/dark box test and Go/No-Go conditioning task revealed that homozygous mutant mice exhibit defective response inhibition, a form of impulsivity. This defect was specific to attention as other tests showed no differences in visually driven behavior, motivation, visuo-spatial learning and sensorimotor abilities among the different groups of mice. Monoamine quantification and gene expression profiling demonstrated a specific enrichment of noradrenaline only in the superficial layers of the superior colliculus of Isl2-EphA3 knock-in mice, where the retinotopy is duplicated, whereas transcript levels of receptors, transporters and metabolic enzymes of the monoaminergic pathway were not affected. We demonstrate that the defect in response inhibition is a consequence of noradrenaline imbalance in the superficial layers of the superior colliculus caused by retinotopic map duplication. Our results suggest that structural abnormalities in the superior colliculus can cause defective response inhibition, a key feature of attention-deficit disorders.

  8. Defective response inhibition and collicular noradrenaline enrichment in mice with duplicated retinotopic map in the superior colliculus.

    PubMed

    Mathis, Chantal; Savier, Elise; Bott, Jean-Bastien; Clesse, Daniel; Bevins, Nicholas; Sage-Ciocca, Dominique; Geiger, Karin; Gillet, Anaïs; Laux-Biehlmann, Alexis; Goumon, Yannick; Lacaud, Adrien; Lelièvre, Vincent; Kelche, Christian; Cassel, Jean-Christophe; Pfrieger, Frank W; Reber, Michael

    2015-01-01

    The superior colliculus is a hub for multisensory integration necessary for visuo-spatial orientation, control of gaze movements and attention. The multiple functions of the superior colliculus have prompted hypotheses about its involvement in neuropsychiatric conditions, but to date, this topic has not been addressed experimentally. We describe experiments on genetically modified mice, the Isl2-EphA3 knock-in line, that show a well-characterized duplication of the retino-collicular and cortico-collicular axonal projections leading to hyperstimulation of the superior colliculus. To explore the functional impact of collicular hyperstimulation, we compared the performance of homozygous knock-in, heterozygous knock-in and wild-type mice in several behavioral tasks requiring collicular activity. The light/dark box test and Go/No-Go conditioning task revealed that homozygous mutant mice exhibit defective response inhibition, a form of impulsivity. This defect was specific to attention as other tests showed no differences in visually driven behavior, motivation, visuo-spatial learning and sensorimotor abilities among the different groups of mice. Monoamine quantification and gene expression profiling demonstrated a specific enrichment of noradrenaline only in the superficial layers of the superior colliculus of Isl2-EphA3 knock-in mice, where the retinotopy is duplicated, whereas transcript levels of receptors, transporters and metabolic enzymes of the monoaminergic pathway were not affected. We demonstrate that the defect in response inhibition is a consequence of noradrenaline imbalance in the superficial layers of the superior colliculus caused by retinotopic map duplication. Our results suggest that structural abnormalities in the superior colliculus can cause defective response inhibition, a key feature of attention-deficit disorders. PMID:24647754

  9. Colour discrimination in the black-tufted-ear marmoset (Callithrix penicillata): ecological implications.

    PubMed

    Pessoa, Daniel M A; Cunha, Juliana F; Tomaz, Carlos; Pessoa, Valdir F

    2005-01-01

    The dietary diversity of marmosets is substantial, which may reflect differences in their colour vision. This study examined the colour discrimination ability of a gummivore/insectivore callitrichid, Callithrix penicillata, which inhabits the Brazilian cerrado (bush savanna). A series of ecologically relevant tasks, involving a behavioural paradigm of discrimination learning in semi-natural conditions and the usage of ecologically relevant stimuli, was executed. Three marmosets, 2 males and a female, behaved like human dichromats, showing an impaired performance when orange and green stimuli had to be discriminated. In contrast, 2 females resembled human trichromats, discriminating those kinds of pairs. Our data suggest that Callithrix penicillata presents a polymorphic trichromacy, with dichromatic males and dichromatic or trichromatic females. PMID:15900100

  10. The common marmoset genome provides insight into primate biology and evolution.

    PubMed

    2014-08-01

    We report the whole-genome sequence of the common marmoset (Callithrix jacchus). The 2.26-Gb genome of a female marmoset was assembled using Sanger read data (6×) and a whole-genome shotgun strategy. A first analysis has permitted comparison with the genomes of apes and Old World monkeys and the identification of specific features that might contribute to the unique biology of this diminutive primate, including genetic changes that may influence body size, frequent twinning and chimerism. We observed positive selection in growth hormone/insulin-like growth factor genes (growth pathways), respiratory complex I genes (metabolic pathways), and genes encoding immunobiological factors and proteases (reproductive and immunity pathways). In addition, both protein-coding and microRNA genes related to reproduction exhibited evidence of rapid sequence evolution. This genome sequence for a New World monkey enables increased power for comparative analyses among available primate genomes and facilitates biomedical research application. PMID:25038751

  11. The puzzle-feeder as feeding enrichment for common marmosets (Callithrix jacchus): a pilot study.

    PubMed

    de Rosa, C; Vitale, A; Puopolo, M

    2003-04-01

    The use of a puzzle-feeder, as feeding enrichment, was investigated in three families of captive common marmosets (Callithrix jacchus). The study was carried out as a simultaneous choice test between two cages: one contained the puzzle-feeder, the other contained the usual food dishes, but otherwise both were arranged similarly. The monkeys were allowed to choose whether to feed from the usual dishes, or from the puzzle-feeder which required more effort. They were observed for two sessions in which they were differently motivated to feed. The enriched cage was always visited first, the marmosets managed to extract food from the puzzle-feeder, and spent more time eating from the puzzle-feeder when less hungry. These data contribute to a wider understanding on the use, and the effects, of feeding enrichments with different captive non-human primates. PMID:12689420

  12. Common marmosets (Callithrix jacchus) do not utilize social information in three simultaneous social foraging tasks.

    PubMed

    Voelkl, Bernhard; Huber, Ludwig

    2007-04-01

    Social foraging is suggested to increase foraging efficiency, as individuals might benefit from public information acquired by monitoring the foraging activities of other group members. We conducted a series experiments with captive common marmosets (Callithrix jacchus) to investigate to what extent marmosets utilize social information about food location when foraging simultaneously with conspecifics. Subjects were confronted with dominant and subordinate demonstrators in three experiments which differed in the amount of information about food location available to the demonstrators. In all three experiments, the focal subjects' performance in the social condition was not enhanced in comparison to a non-social control condition. Because we could rule out kleptoparasitism and aggressive displacements as explanations, we argue that the subjects' tendency for scramble competition by avoiding others and dispersing over the foraging area seems to inhibit or mask the acquisition of social information about the location of rewarded patches.

  13. Functional capabilities of marmoset T and B lymphocytes in primary in vitro antibody formation

    SciTech Connect

    Nickerson, D.A.; Gengozian, N.

    1981-01-15

    In vitro tests of T- and B-lymphocyte function of two marmoset species, Saguinus fuscicollis and Saguinus oedipus, were examined to explore the lower immune response profile previously reported for S. o. oedipus. Experiments with trinitrophenyl-lipopolysaccharide (TNP-LPS) revealed peripheral blood leukocytes (PBL) from both species capable of antibody formation. This response was both T cell and monocyte independent; indeed, removal of T cells led to an enhanced response, indicating a regulatory role for this cell in each species. Studies with the nonmitogenic form of TNP-LPS, trinitrophenyl-base-hydrolyzed-lipopolysaccharide, revealed that plaque-forming cells could be obtained from S. fuscicollis PBL while S. o. oedipus PBL were unresponsive. This report also demonstrates that hemopoietic chimerism, a feature common to all marmosets, has a negative influence on antibody-forming capabilities.

  14. The Common Marmoset Genome Provides Insight into Primate Biology and Evolution

    PubMed Central

    2014-01-01

    A first analysis of the genome sequence of the common marmoset (Callithrix jacchus), assembled using traditional Sanger methods and Ensembl annotation, has permitted genomic comparison with apes and old world monkeys and the identification of specific molecular features that may contribute to the unique biology of this diminutive primate. The common marmoset has a rapid reproductive capacity partly due to prevalence of dizygotic twins. Remarkably, these twins share placental circulation and exchange hematopoietic stem cells in utero, resulting in adults that are hematopoietic chimeras. We observed positive selection or non-synonymous substitutions for genes encoding growth hormone/insulin-like growth factor (growth pathways), respiratory complex I (metabolic pathways), immunobiology, and proteases (reproductive and immunity pathways). In addition, both protein-coding and microRNA genes related to reproduction exhibit rapid sequence evolution. This New World monkey genome sequence enables significantly increased power for comparative analyses among available primate genomes and facilitates biomedical research application. PMID:25038751

  15. The Zona Incerta Regulates Communication between the Superior Colliculus and the Posteromedial Thalamus: Implications for Thalamic Interactions with the Dorsolateral Striatum

    PubMed Central

    Watson, Glenn D.R.; Smith, Jared B.

    2015-01-01

    There is uncertainty concerning the circuit connections by which the superior colliculus interacts with the basal ganglia. To address this issue, anterograde and retrograde tracers were placed, respectively, into the superior colliculus and globus pallidus of Sprague-Dawley rats. In this two-tracer experiment, the projections from the superior colliculus terminated densely in the ventral zona incerta (ZIv), but did not overlap the labeled neurons observed in the subthalamic nucleus. In cases in which anterograde and retrograde tracers were placed, respectively, in sensory-responsive sites in the superior colliculus and posteromedial (POm) thalamus, the labeled projections from superior colliculus innervated the ZIv regions that contained the labeled neurons that project to POm. We also confirmed this colliculo–incertal–POm pathway by depositing a mixture of retrograde and anterograde tracers at focal sites in ZIv to reveal retrogradely labeled neurons in superior colliculus and anterogradely labeled terminals in POm. When combined with retrograde tracer injections in POm, immunohistochemical processing proved that most ZIv projections to POm are GABAergic. Consistent with these findings, direct stimulation of superior colliculus evoked neuronal excitation in ZIv and caused inhibition of spontaneous activity in POm. Collectively, these results indicate that superior colliculus can activate the inhibitory projections from ZIv to the POm. This is significant because it suggests that the superior colliculus could suppress the interactions between POm and the dorsolateral striatum, presumably to halt ongoing behaviors so that more adaptive motor actions are selected in response to unexpected sensory events. SIGNIFICANCE STATEMENT By demonstrating that the zona incerta regulates communication between the superior colliculus and the posteromedial thalamus, we have uncovered a circuit that partly explains the behavioral changes that occur in response to unexpected

  16. Neurophysiological study on sensorimotor control mechanism in superior colliculus of echolocating bat.

    PubMed

    Li, Yao; Song, Y D

    2007-04-01

    This paper investigates the neural processes associated with bat sonar vocal production and their relationship with spatial orientation. The bat's heavy reliance on sound processing is reflected in specializations of auditory and motor neural structures. These specializations were utilized by investigating the mammalian superior colliculus (SC); a midbrain sensory motor nucleus mediating orientating behaviours in mammals, including vocal motor orientating. Behavioural and neurophysiological experiments were conducted in the insectivorous echolocating bat, Eptesicus fuscus. Chronic neural recording techniques were specifically developed to study neuronal activity. Potential application of the results on control systems is also addressed.

  17. Non-viral generation of marmoset monkey iPS cells by a six-factor-in-one-vector approach.

    PubMed

    Debowski, Katharina; Warthemann, Rita; Lentes, Jana; Salinas-Riester, Gabriela; Dressel, Ralf; Langenstroth, Daniel; Gromoll, Jörg; Sasaki, Erika; Behr, Rüdiger

    2015-01-01

    Groundbreaking studies showed that differentiated somatic cells of mouse and human origin could be reverted to a stable pluripotent state by the ectopic expression of only four proteins. The resulting pluripotent cells, called induced pluripotent stem (iPS) cells, could be an alternative to embryonic stem cells, which are under continuous ethical debate. Hence, iPS cell-derived functional cells such as neurons may become the key for an effective treatment of currently incurable degenerative diseases. However, besides the requirement of efficacy testing of the therapy also its long-term safety needs to be carefully evaluated in settings mirroring the clinical situation in an optimal way. In this context, we chose the long-lived common marmoset monkey (Callithrix jacchus) as a non-human primate species to generate iPS cells. The marmoset monkey is frequently used in biomedical research and is gaining more and more preclinical relevance due to the increasing number of disease models. Here, we describe, to our knowledge, the first-time generation of marmoset monkey iPS cells from postnatal skin fibroblasts by non-viral means. We used the transposon-based, fully reversible piggyback system. We cloned the marmoset monkey reprogramming factors and established robust and reproducible reprogramming protocols with a six-factor-in-one-construct approach. We generated six individual iPS cell lines and characterized them in comparison with marmoset monkey embryonic stem cells. The generated iPS cells are morphologically indistinguishable from marmoset ES cells. The iPS cells are fully reprogrammed as demonstrated by differentiation assays, pluripotency marker expression and transcriptome analysis. They are stable for numerous passages (more than 80) and exhibit euploidy. In summary, we have established efficient non-viral reprogramming protocols for the derivation of stable marmoset monkey iPS cells, which can be used to develop and test cell replacement therapies in

  18. Cellular Composition and Organization of the Subventricular Zone and Rostral Migratory Stream in the Adult and Neonatal Common Marmoset Brain

    PubMed Central

    Sawamoto, Kazunobu; Hirota, Yuki; Alfaro-Cervello, Clara; Soriano-Navarro, Mario; He, Xiaoping; Hayakawa-Yano, Yoshika; Yamada, Masayuki; Hikishima, Keigo; Tabata, Hidenori; Iwanami, Akio; Nakajima, Kazunori; Toyama, Yoshiaki; Itoh, Toshio; Alvarez-Buylla, Arturo; Garcia-Verdugo, Jose Manuel; Okano, Hideyuki

    2014-01-01

    The adult subventricular zone (SVZ) of the lateral ventricle contains neural stem cells. In rodents, these cells generate neuroblasts that migrate as chains toward the olfactory bulb along the rostral migratory stream (RMS). The neural-stem-cell niche at the ventricular wall is conserved in various animal species, including primates. However, it is unclear how the SVZ and RMS organization in nonhuman primates relates to that of rodents and humans. Here we studied the SVZ and RMS of the adult and neonatal common marmoset (Callithrix jacchus), a New World primate used widely in neuroscience, by electron microscopy, and immunohistochemical detection of cell-type-specific markers. The marmoset SVZ contained cells similar to type B, C, and A cells of the rodent SVZ in their marker expression and morphology. The adult marmoset SVZ had a three-layer organization, as in the human brain, with ependymal, hypocellular, and astro-cyte-ribbon layers. However, the hypocellular layer was very thin or absent in the adult-anterior and neonatal SVZ. Anti-PSA-NCAM staining of the anterior SVZ in whole-mount ventricular wall preparations of adult marmosets revealed an extensive network of elongated cell aggregates similar to the neuroblast chains in rodents. Time-lapse recordings of marmoset SVZ explants cultured in Matrigel showed the neuroblasts migrating in chains, like rodent type A cells. These results suggest that some features of neurogenesis and neuronal migration in the SVZ are common to marmosets, humans, and rodents. This basic description of the adult and neonatal marmoset SVZ will be useful for future studies on adult neurogenesis in primates. PMID:21246550

  19. Modeling Parkinson's disease in the common marmoset (Callithrix jacchus): overview of models, methods, and animal care

    PubMed Central

    Yun, Jun-Won; Ahn, Jae-Bum

    2015-01-01

    The common marmoset (Callithrix jacchus) is a small-bodied, popular New World monkey and is used widely in reproductive biology, neuroscience, and drug development, due to its comparative ease of handling, high reproductive efficiency, and its unique behavioral characters. In this review, we discuss the marmoset models in Parkinson's disease (PD), which is a neurological movement disorder primarily resulting from a degeneration of dopaminergic neurons with clinical features of tremor, rigidity, postural instability, and akinesia. The most common PD models involve the administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 6-hydroxydopamine to study the pathogenesis and to evaluate novel therapies. Following the systemic or local administration of these neurotoxins, the marmosets with very severe Parkinson's symptoms are recommended to be placed in an intensive care unit with artificial feeding to increase survival rate. All procedures with MPTP should be conducted in a special room with enclosed cages under negative-pressure by trained researchers with personal protection. Behavioral tests are conducted to provide an external measure of the brain pathology. Along with several biomarkers, including α-synuclein and DJ-1, non-invasive neuroimaging techniques such as positron emission tomography and magnetic resonance imaging are used to evaluate the functional changes associated with PD. With the recent growing interest in potential and novel therapies such as stem cell and gene therapy for PD in Korea, the marmoset can be considered as a suitable non-human primate model in PD research to bridge the gap between rodent studies and clinical applications. PMID:26755918

  20. In Vivo Two-Photon Imaging of Dendritic Spines in Marmoset Neocortex1,2,3

    PubMed Central

    Sadakane, Osamu; Watakabe, Akiya; Ohtsuka, Masanari; Takaji, Masafumi; Sasaki, Tetsuya; Kasai, Masatoshi; Isa, Tadashi; Kato, Go; Nabekura, Junichi; Mizukami, Hiroaki; Ozawa, Keiya; Kawasaki, Hiroshi

    2015-01-01

    Abstract Two-photon microscopy in combination with a technique involving the artificial expression of fluorescent protein has enabled the direct observation of dendritic spines in living brains. However, the application of this method to primate brains has been hindered by the lack of appropriate labeling techniques for visualizing dendritic spines. Here, we developed an adeno-associated virus vector-based fluorescent protein expression system for visualizing dendritic spines in vivo in the marmoset neocortex. For the clear visualization of each spine, the expression of reporter fluorescent protein should be both sparse and strong. To fulfill these requirements, we amplified fluorescent signals using the tetracycline transactivator (tTA)–tetracycline-responsive element system and by titrating down the amount of Thy1S promoter-driven tTA for sparse expression. By this method, we were able to visualize dendritic spines in the marmoset cortex by two-photon microscopy in vivo and analyze the turnover of spines in the prefrontal cortex. Our results demonstrated that short spines in the marmoset cortex tend to change more frequently than long spines. The comparison of in vivo samples with fixed samples showed that we did not detect all existing spines by our method. Although we found glial cell proliferation, the damage of tissues caused by window construction was relatively small, judging from the comparison of spine length between samples with or without window construction. Our new labeling technique for two-photon imaging to visualize in vivo dendritic spines of the marmoset neocortex can be applicable to examining circuit reorganization and synaptic plasticity in primates. PMID:26465000

  1. Transmission of colour and acuity signals by parvocellular cells in marmoset monkeys.

    PubMed

    Martin, Paul R; Blessing, Esther M; Buzás, Péter; Szmajda, Brett A; Forte, Jason D

    2011-06-01

    The red-green axis of colour vision evolved recently in primate evolutionary history. Signals serving red-green colour vision travel together with signals serving spatial vision, in the parvocellular (PC) division of the subcortical visual pathway. However, the question of whether receptive fields of PC pathway cells are specialized to transmit red-green colour signals remains unresolved. We addressed this question in single-cell recordings from the lateral geniculate nucleus of anaesthetized marmosets. Marmosets show a high proportion of dichromatic (red-green colour-blind) individuals, allowing spatial and colour tuning properties of PC cells to be directly compared in dichromatic and trichromatic visual systems. We measured spatial frequency tuning for sine gratings that provided selective stimulation of individual photoreceptor types. We found that in trichromatic marmosets, the foveal visual field representation is dominated by red-green colour-selective PC cells. Colour selectivity of PC cells is reduced at greater eccentricities, but cone inputs to centre and surround are biased to create more selectivity than predicted by a purely 'random wiring' model. Thus, one-to-one connections in the fovea are sufficient, but not necessary, to create colour-selective responses. The distribution of spatial tuning properties for achromatic stimuli shows almost complete overlap between PC cells recorded in dichromatic and trichromatic marmosets. These data indicate that transmission of red-green colour signals has been enabled by centre-surround receptive fields of PC cells, and has not altered the capacity of PC cells to serve high-acuity vision at high stimulus contrast. PMID:21486786

  2. IgG+ platelets in the marmoset: their induction, maintenance, and survival

    SciTech Connect

    Gengozian, N.; McLaughlin, C.L.

    1980-06-01

    Immunization of marmosets with platelets from another species of marmoset leads to antibody formation to the donor platelets, deposition of IgG on the host's platelets, and thrombocytopenia. This disease closely resembles posttransfusion purpura of man, which may develop after one or two transfusions of whole blood. The mode of immunization in the marmoset was found to be important: intravenous (i.v.) inoculations were without effect, while intramuscular (i.m.) immunizations led to the disease. Intramuscular inoculations were characterized by formation of 7S antibodies, as measured by indirect immunofluorescent (IF) and complement-dependent platelet cytotoxicity (PC) tests; in contrast, i.v. immunizations, while leading to 7S antibodies by the IF test, yielded only 19S antibodies reactive in the PC assay. The titers were also consistently higher with i.m. immunizations. Antibody was not limited to the donor platelets, but auto- or host-type reactivity was also present; this antibody was in very low titer and could be found only when the animal was thrombocytopenic. A primary finding was the ability to maintain increased deposition of IgG on the host's platelets in the absence of thrombocytopenia by biweekly or monthly inoculations of the donor platelet antigen. The amount of IgG found on platelets of normal and immunized marmosets was comparable to that reported for normal humans and patients with cinical immune thrombocytopenia. Finally, platelet survival studies in animals with IgG+ platelets and normal platelet counts indicated a rapid turnover, suggesting operation of a compensatory mechanism to maintain platelet levels.

  3. Seizures triggered by pentylenetetrazol in marmosets made chronically epileptic with pilocarpine show greater refractoriness to treatment.

    PubMed

    Pontes, Josy Carolina C; Lima, Thiago Z; Queiroz, Claudio M; Cinini, Simone M; Blanco, Miriam M; Mello, Luiz E

    2016-10-01

    The efficiency of most of the new antiepileptic drugs (AEDs) on clinical trials still falls short the success reported in pre-clinical studies, possibly because the validity of the animal models is insufficient to fully represent the human pathology. To improve the translational value for testing AEDs, we propose the use of non-human primates. Here, we suggest that triggering limbic seizures with low doses of PTZ in pilocarpine-treated marmosets might provide a more effective basis for the development of AED. Marmosets with epileptic background were more susceptible to seizures induced by PTZ, which were at least 3 times longer and more severe (about 6 times greater frequency of generalized seizures) in comparison to naïve peers. Accordingly, PTZ-induced seizures were remarkably less attenuated by AEDs in epileptic than naïve marmosets. While phenobarbital (40mg/kg) virtually abolished seizures regardless of the animal's background, carbamazepine (120mg/kg) and valproic acid (400mg/kg) could not prevent PTZ-induced seizures in epileptic animals with the same efficiency as observed in naïve peers. VPA was less effective regarding the duration of individual seizures in epileptic animals, as assessed in ECoG (p=0.05). Similarly following CBZ treatment, the behavioral manifestation of generalized seizures lasted longer in epileptic (p<0.05), which were also more frequent than in the naïve group (p<0.05). As expected, epileptic marmosets experiencing stronger seizures showed more NPY- and ΔFosB-immunostained neurons in a number of brain areas associated with the generation and spread of limbic seizures. Our results suggest that PTZ induced seizures over an already existing epileptic background constitutes a reliable and controllable mean for the screening of new AEDs.

  4. Toward a nonhuman primate model of fetal programming: phenotypic plasticity of the common marmoset fetoplacental complex

    PubMed Central

    Rutherford, Julienne N.

    2012-01-01

    Nonhuman primate models offer unique opportunities as animal models in the study of developmental programming and the role of the placenta in developmental processes. All primates share fundamental similarities in life history and reproductive biology. Thus, insights gleaned from studies of nonhuman primates have a higher degree of biological salience to human biology than do studies of rodents or agricultural animals. The common marmoset monkey is a small-bodied primate from South America that produces litters of dizygotic fetuses that share a single placental mass. This natural variation allows us to model different intrauterine conditions and associated fetoplacental phenotypes. The marmoset placenta is phenotypically plastic according to litter size. Triplet litters are characterized by low individual fetal weights and significantly more efficient placentas and attendant alterations to the microscopic architecture and endocrine function, thus modeling a nutrient restricted intrauterine environment. Consistent with this model, triplet neonates experience a higher risk of perinatal mortality and an increased likelihood of elevated adult weight. Recent evidence has shown that the intrauterine experience of females has an impact on their own pregnancy outcomes in adulthood: triplet females experience significantly greater pregnancy loss than do twin females. The marmoset monkey thus represents a potential powerful nonhuman primate model of multiple pregnancies, restrictive prenatal experiences, and differential reproductive outcomes in adulthood, which may have important implications for studying the impact of in vitro fertilization on adult reproductive health. It is still too early to determine exactly what developmental pathways lead to this disparity or what specific role the placenta plays; future work on this front will be critical to establish the marmoset as an important model of fetal programming of reproductive function in adulthood and across generations

  5. The marmoset monkey: a multi-purpose preclinical and translational model of human biology and disease.

    PubMed

    't Hart, Bert A; Abbott, David H; Nakamura, Katsuki; Fuchs, Eberhard

    2012-11-01

    The development of biologic molecules (monoclonal antibodies, cytokines, soluble receptors) as specific therapeutics for human disease creates a need for animal models in which safety and efficacy can be tested. Models in lower animal species are precluded when the reagents fail to recognize their targets, which is often the case in rats and mice. In this Feature article we will highlight the common marmoset, a small-bodied nonhuman primate (NHP), as a useful model in biomedical and preclinical translational research.

  6. Mismatch negativity in common marmosets: Whole-cortical recordings with multi-channel electrocorticograms.

    PubMed

    Komatsu, Misako; Takaura, Kana; Fujii, Naotaka

    2015-01-01

    Mismatch negativity (MMN) is a component of event-related potentials (ERPs) evoked by violations of regularity in sensory stimulus-series in humans. Recently, the MMN has received attention as a clinical and translatable biomarker of psychiatric disorders such as schizophrenia, and for the development animal models of these psychiatric disorders. In this study, we investigated the generation of MMN in common marmosets, which are an important non-human primate model with genetic manipulability. We recorded the electrocorticograms (ECoGs) from two common marmosets with epidurally implanted electrodes covering a wide range of cortical regions. ECoG recordings were conducted in a passive listening condition with a roving oddball paradigm. We compared the ERPs evoked by repeatedly presented standard stimuli and those evoked by the deviant stimuli. Significant differences in the ERPs were observed in several cortical areas. In particular, deviant stimuli elicited larger negative activity than standard stimuli in the temporal area. In addition, the latency and polarity of the activity were comparable to human MMNs. This is thus the first report of MMN-like activity in common marmosets. Our findings have the potential to advance future gene-manipulation studies that aim to establish non-human primate models of schizophrenia. PMID:26456147

  7. Comparative experimental subcutaneous glanders and melioidosis in the common marmoset (Callithrix jacchus)

    PubMed Central

    Nelson, Michelle; Salguero, Francisco J; Dean, Rachel E; Ngugi, Sarah A; Smither, Sophie J; Atkins, Timothy P; Lever, Mark S

    2014-01-01

    Glanders and melioidosis are caused by two distinct Burkholderia species and have generally been considered to have similar disease progression. While both of these pathogens are HHS/CDC Tier 1 agents, natural infection with both these pathogens is primarily through skin inoculation. The common marmoset (Callithrix jacchus) was used to compare disease following experimental subcutaneous challenge. Acute, lethal disease was observed in marmosets following challenge with between 26 and 1.2 × 108 cfu Burkholderia pseudomallei within 22–85 h. The reproducibility and progression of the disease were assessed following a challenge of 1 × 102 cfu of B. pseudomallei. Melioidosis was characterised by high levels of bacteraemia, focal microgranuloma progressing to non-necrotic multifocal solid lesions in the livers and spleens and multi-organ failure. Lethal disease was observed in 93% of animals challenged with Burkholderia mallei, occurring between 5 and 10.6 days. Following challenge with 1 × 102 cfu of B. mallei, glanders was characterised with lymphatic spread of the bacteria and non-necrotic, multifocal solid lesions progressing to a multifocal lesion with severe necrosis and pneumonia. The experimental results confirmed that the disease pathology and presentation is strikingly different between the two pathogens. The marmoset provides a model of the human syndrome for both diseases facilitating the development of medical countermeasures. PMID:25477002

  8. Comparative experimental subcutaneous glanders and melioidosis in the common marmoset (Callithrix jacchus).

    PubMed

    Nelson, Michelle; Salguero, Francisco J; Dean, Rachel E; Ngugi, Sarah A; Smither, Sophie J; Atkins, Timothy P; Lever, Mark S

    2014-12-01

    Glanders and melioidosis are caused by two distinct Burkholderia species and have generally been considered to have similar disease progression. While both of these pathogens are HHS/CDC Tier 1 agents, natural infection with both these pathogens is primarily through skin inoculation. The common marmoset (Callithrix jacchus) was used to compare disease following experimental subcutaneous challenge. Acute, lethal disease was observed in marmosets following challenge with between 26 and 1.2 × 10(8) cfu Burkholderia pseudomallei within 22-85 h. The reproducibility and progression of the disease were assessed following a challenge of 1 × 10(2) cfu of B. pseudomallei. Melioidosis was characterised by high levels of bacteraemia, focal microgranuloma progressing to non-necrotic multifocal solid lesions in the livers and spleens and multi-organ failure. Lethal disease was observed in 93% of animals challenged with Burkholderia mallei, occurring between 5 and 10.6 days. Following challenge with 1 × 10(2) cfu of B. mallei, glanders was characterised with lymphatic spread of the bacteria and non-necrotic, multifocal solid lesions progressing to a multifocal lesion with severe necrosis and pneumonia. The experimental results confirmed that the disease pathology and presentation is strikingly different between the two pathogens. The marmoset provides a model of the human syndrome for both diseases facilitating the development of medical countermeasures.

  9. Demonstration of a foraging advantage for trichromatic marmosets (Callithrix geoffroyi) dependent on food colour.

    PubMed Central

    Caine, N G; Mundy, N I

    2000-01-01

    It has been suggested that the major advantage of trichromatic over dichromatic colour vision in primates is enhanced detection of red/yellow food items such as fruit against the dappled foliage of the forest. This hypothesis was tested by comparing the foraging ability of dichromatic and trichromatic Geoffroy's marmosets (Callithrix geoffroyi) for orange- and green-coloured cereal balls (Kix) in a naturalized captive setting. Trichromatic marmosets found a significantly greater number of orange, but not green, Kix than dichromatic marmosets when the food items were scattered on the floor of the cage (at a potential detection distance of up to 6 m from the animals). Under these conditions, trichromats but not dichromats found significantly more orange than green Kix, an effect that was also evident when separately examining the data from the end of the trials, when the least conspicuous Kix were left. In contrast, no significant differences among trichromats and dichromats were seen when the Kix were placed in trays among green wood shavings (detection distance < 0.5 m). These results support an advantage for trichromats in detecting orange-coloured food items against foliage, and also suggest that this advantage may be less important at shorter distances. If such a foraging advantage for trichromats is present in the wild it might be sufficient to maintain the colour vision polymorphism seen in the majority of New World monkeys. PMID:10737399

  10. MRI-guided stereotaxic brain surgery in the infant and adult common marmoset.

    PubMed

    Mundinano, Inaki-Carril; Flecknell, Paul A; Bourne, James A

    2016-07-01

    In the past decade, the New World common marmoset (Callithrix jacchus) has taken a seminal position in neurobiological research, fueled in part by its smooth cortical sheet, which allows cortical areas to be easily accessed by current technologies on the dorsal surface of the brain. In this protocol, we describe a method for the precision placement of agents (e.g., tracers or neurotoxins) into small brain regions of the infant and adult marmoset, using an MRI-guided approach. This strategy uses a protocol for prolonged anesthesia without the need for intubation that we have recently developed, alongside appropriate analgesia and monitoring. The protocol can be readily adapted to be used together with advanced research techniques, such as two-photon microscopy and optical imaging. Including a 5-d postoperative care plan, this protocol takes 7 d to complete. The protocol requires a team of personnel experienced in marmoset care and handling, and small-animal neurosurgery; an assistant for monitoring the animal and assisting with anesthesia; and an MRI technician. PMID:27336707

  11. Long-Term Oocyte-Like Cell Development in Cultures Derived from Neonatal Marmoset Monkey Ovary

    PubMed Central

    Fereydouni, Bentolhoda; Salinas-Riester, Gabriela; Heistermann, Michael; Dressel, Ralf; Lewerich, Lucia; Drummer, Charis; Behr, Rüdiger

    2016-01-01

    We use the common marmoset monkey (Callithrix jacchus) as a preclinical nonhuman primate model to study reproductive and stem cell biology. The neonatal marmoset monkey ovary contains numerous primitive premeiotic germ cells (oogonia) expressing pluripotent stem cell markers including OCT4A (POU5F1). This is a peculiarity compared to neonatal human and rodent ovaries. Here, we aimed at culturing marmoset oogonia from neonatal ovaries. We established a culture system being stable for more than 20 passages and 5 months. Importantly, comparative transcriptome analysis of the cultured cells with neonatal ovary, embryonic stem cells, and fibroblasts revealed a lack of germ cell and pluripotency genes indicating the complete loss of oogonia upon initiation of the culture. From passage 4 onwards, however, the cultured cells produced large spherical, free-floating cells resembling oocyte-like cells (OLCs). OLCs strongly expressed several germ cell genes and may derive from the ovarian surface epithelium. In summary, our novel primate ovarian cell culture initially lacked detectable germ cells but then produced OLCs over a long period of time. This culture system may allow a deeper analysis of early phases of female primate germ cell development and—after significant refinement—possibly also the production of monkey oocytes. PMID:26664406

  12. Metabolic consequences of long-term rapamycin exposure on common marmoset monkeys (Callithrix jacchus).

    PubMed

    Ross, Corinna; Salmon, Adam; Strong, Randy; Fernandez, Elizabeth; Javors, Marty; Richardson, Arlan; Tardif, Suzette

    2015-11-01

    Rapamycin has been shown to extend lifespan in rodent models, but the effects on metabolic health and function have been widely debated in both clinical and translational trials. Prior to rapamycin being used as a treatment to extend both lifespan and healthspan in the human population, it is vital to assess the side effects of the treatment on metabolic pathways in animal model systems, including a closely related non-human primate model. In this study, we found that long-term treatment of marmoset monkeys with orally-administered encapsulated rapamycin resulted in no overall effects on body weight and only a small decrease in fat mass over the first few months of treatment. Rapamycin treated subjects showed no overall changes in daily activity counts, blood lipids, or significant changes in glucose metabolism including oral glucose tolerance. Adipose tissue displayed no differences in gene expression of metabolic markers following treatment, while liver tissue exhibited suppressed G6Pase activity with increased PCK and GPI activity. Overall, the marmosets revealed only minor metabolic consequences of chronic treatment with rapamycin and this adds to the growing body of literature that suggests that chronic and/or intermittent rapamycin treatment results in improved health span and metabolic functioning. The marmosets offer an interesting alternative animal model for future intervention testing and translational modeling. PMID:26568298

  13. Metabolic consequences of long-term rapamycin exposure on common marmoset monkeys (Callithrix jacchus)

    PubMed Central

    Ross, Corinna; Salmon, Adam; Strong, Randy; Fernandez, Elizabeth; Javors, Marty; Richardson, Arlan; Tardif, Suzette

    2015-01-01

    Rapamycin has been shown to extend lifespan in rodent models, but the effects on metabolic health and function have been widely debated in both clinical and translational trials. Prior to rapamycin being used as a treatment to extend both lifespan and healthspan in the human population, it is vital to assess the side effects of the treatment on metabolic pathways in animal model systems, including a closely related non-human primate model. In this study, we found that long-term treatment of marmoset monkeys with orally-administered encapsulated rapamycin resulted in no overall effects on body weight and only a small decrease in fat mass over the first few months of treatment. Rapamycin treated subjects showed no overall changes in daily activity counts, blood lipids, or significant changes in glucose metabolism including oral glucose tolerance. Adipose tissue displayed no differences in gene expression of metabolic markers following treatment, while liver tissue exhibited suppressed G6Pase activity with increased PCK and GPI activity. Overall, the marmosets revealed only minor metabolic consequences of chronic treatment with rapamycin and this adds to the growing body of literature that suggests that chronic and/or intermittent rapamycin treatment results in improved health span and metabolic functioning. The marmosets offer an interesting alternative animal model for future intervention testing and translational modeling. PMID:26568298

  14. Individual Differences in Gambling Proneness among Rats and Common Marmosets: An Automated Choice Task

    PubMed Central

    Manciocco, Arianna; Vitale, Augusto; Laviola, Giovanni

    2014-01-01

    Interest is rising for animal modeling of pathological gambling. Using the operant probabilistic-delivery task (PDT), gambling proneness can be evaluated in laboratory animals. Drawing a comparison with rats, this study evaluated the common marmoset (Callithrix jacchus) using a PDT. By nose- or hand-poking, subjects learnt to prefer a large (LLL, 5-6 pellets) over a small (SS, 1-2 pellets) reward and, subsequently, the probability of occurrence of large-reward delivery was decreased progressively to very low levels (from 100% to 17% and 14%). As probability decreased, subjects showed a great versus little shift in preference from LLL to SS reinforcer. Hence, two distinct subpopulations (“non-gambler” versus “gambler”) were differentiated within each species. A proof of the model validity comes from marmosets' reaction to reward-delivery omission. Namely, depending on individual temperament (“gambler” versus “non-gambler”), they showed either persistence (i.e., inadequate pokes towards LLL) or restlessness (i.e., inadequate pokes towards SS), respectively. In conclusion, the marmoset could be a suitable model for preclinical gambling studies. Implementation of the PDT to species other than rats may be relevant for determining its external validity/generalizability and improving its face/construct validity. PMID:24971360

  15. Mosaic properties of midget and parasol ganglion cells in the marmoset retina.

    PubMed

    Szmajda, Brett A; Grünert, Ulrike; Martin, Paul R

    2005-01-01

    We measured mosaic properties of midget and parasol ganglion cells in the retina of a New World monkey, the common marmoset Callithrix jacchus . We addressed the functional specialization of these populations for color and spatial vision, by comparing the mosaic of ganglion cells in dichromatic ("red-green color blind") and trichromatic marmosets. Ganglion cells were labelled by photolytic amplification of retrograde marker ("photofilling") following injections into the lateral geniculate nucleus, or by intracellular injection in an in vitro retinal preparation. The dendritic-field size, shape, and overlap of neighboring cells were measured. We show that in marmosets, both midget and parasol cells exhibit a radial bias, so that the long axis of the dendritic field points towards the fovea. The radial bias is similar for parasol cells and midget cells, despite the fact that midget cell dendritic fields are more elongated than are those of parasol cells. The dendritic fields of midget ganglion cells from the same (ON or OFF) response-type array show very little overlap, consistent with the low coverage of the midget mosaic in humans. No large differences in radial bias, or overlap, were seen on comparing retinae from dichromatic and trichromatic animals. These data suggest that radial bias in ganglion cell populations is a consistent feature of the primate retina. Furthermore, they suggest that the mosaic properties of the midget cell population are associated with high spatial resolution rather than being specifically associated with trichromatic color vision. PMID:16212698

  16. Experimental Infection of Rhesus Macaques and Common Marmosets with a European Strain of West Nile Virus

    PubMed Central

    Verstrepen, Babs E.; Fagrouch, Zahra; van Heteren, Melanie; Buitendijk, Hester; Haaksma, Tom; Beenhakker, Niels; Palù, Giorgio; Richner, Justin M.; Diamond, Michael S.; Bogers, Willy M.; Barzon, Luisa; Chabierski, Stefan; Ulbert, Sebastian; Kondova, Ivanela; Verschoor, Ernst J.

    2014-01-01

    West Nile virus (WNV) is a mosquito-borne flavivirus that infects humans and other mammals. In some cases WNV causes severe neurological disease. During recent years, outbreaks of WNV are increasing in worldwide distribution and novel genetic variants of the virus have been detected. Although a substantial amount of data exists on WNV infections in rodent models, little is known about early events during WNV infection in primates, including humans. To gain a deeper understanding of this process, we performed experimental infections of rhesus macaques and common marmosets with a virulent European WNV strain (WNV-Ita09) and monitored virological, hematological, and biochemical parameters. WNV-Ita09 productively infected both monkey species, with higher replication and wider tissue distribution in common marmosets compared to rhesus macaques. The animals in this study however, did not develop clinical signs of WNV disease, nor showed substantial deviations in clinical laboratory parameters. In both species, the virus induced a rapid CD56dimCD16bright natural killer response, followed by IgM and IgG antibody responses. The results of this study show that healthy rhesus macaques and common marmosets are promising animal models to study WNV-Ita09 infection. Both models may be particularly of use to evaluate potential vaccine candidates or to investigate WNV pathogenesis. PMID:24743302

  17. Resequencing of the common marmoset genome improves genome assemblies and gene-coding sequence analysis

    PubMed Central

    Sato, Kengo; Kuroki, Yoko; Kumita, Wakako; Fujiyama, Asao; Toyoda, Atsushi; Kawai, Jun; Iriki, Atsushi; Sasaki, Erika; Okano, Hideyuki; Sakakibara, Yasubumi

    2015-01-01

    The first draft of the common marmoset (Callithrix jacchus) genome was published by the Marmoset Genome Sequencing and Analysis Consortium. The draft was based on whole-genome shotgun sequencing, and the current assembly version is Callithrix_jacches-3.2.1, but there still exist 187,214 undetermined gap regions and supercontigs and relatively short contigs that are unmapped to chromosomes in the draft genome. We performed resequencing and assembly of the genome of common marmoset by deep sequencing with high-throughput sequencing technology. Several different sequence runs using Illumina sequencing platforms were executed, and 181 Gbp of high-quality bases including mate-pairs with long insert lengths of 3, 8, 20, and 40 Kbp were obtained, that is, approximately 60× coverage. The resequencing significantly improved the MGSAC draft genome sequence. The N50 of the contigs, which is a statistical measure used to evaluate assembly quality, doubled. As a result, 51% of the contigs (total length: 299 Mbp) that were unmapped to chromosomes in the MGSAC draft were merged with chromosomal contigs, and the improved genome sequence helped to detect 5,288 new genes that are homologous to human cDNAs and the gaps in 5,187 transcripts of the Ensembl gene annotations were completely filled. PMID:26586576

  18. Unrearable litters and prenatal reduction of litter size in the common marmoset (Callithrix jacchus).

    PubMed

    Windle, C P; Baker, H F; Ridley, R M; Oerke, A K; Martin, R D

    1999-04-01

    It is widely believed that common marmosets (Callithrx jacchus) typically give birth to twins under natural conditions. In captivity, however, births of triplets or even larger litters are common, although parents rarely succeed in rearing more than two offspring. The traditional interpretation is that captive conditions, notably the ready availability of food, have led to increased reproductive output, perhaps involving a higher ovulation rate. The present paper provides evidence, combined from ultrasound examinations between ovulation and birth and hysterotomies conducted during the late embryonic and early fetal phase, that the litter size can be progressively reduced during pregnancy without spontaneous abortion. There is an unusually long lag phase prior to the onset of embryonic growth in common marmosets; the fetal stage does not begin until day 80 of the 144-day pregnancy. Reduction in litter size occurs during embryonic stages (up to day 80), and continues into the fetal stages. These results indicate that the common marmoset is adapted for flexible modification of litter size between ovulation and birth. The high incidence of triplet births in captive colonies may therefore be an expression of an adapted natural developmental process under artificial circumstances.

  19. Can wild common marmosets (Callithrix jacchus) solve the parallel strings task?

    PubMed

    Halsey, L G; Bezerra, B M; Souto, A S

    2006-07-01

    Patterned string tasks are a test of perceptual capacity and the understanding of means-end connections. Primates can solve complex forms of this task in laboratories. However, this may not indicate the level of such cognition that is commonly employed in the wild, where decision-making time is often short and distractions such as predator avoidance and competition between conspecifics are often prevalent. The current study tests whether wild common marmosets (Callithrix jacchus) can successfully complete the simplest form of the patterned string task, parallel strings, while in their natural environment. Although 12 out of 13 marmosets could successfully complete the task, in previous laboratory-based studies on primates, the errors at this task by all primate species tested were consistently lower than in the present study. This is probably explained by the added difficulties imposed by the natural setting of the task in the present study, exemplified by a significant increase in observed vigilance behaviour by subject animals prior to attempts at the task that were unsuccessful. The undertaking of such tasks by common marmosets in situ probably provides a more reasonable representation of the levels of cognitive capacity expressed by this species in the wild than do laboratory-based studies of the task.

  20. Home cage presentation of complex discrimination tasks to marmosets and rhesus monkeys.

    PubMed

    Crofts, H S; Muggleton, N G; Bowditch, A P; Pearce, P C; Nutt, D J; Scott, E A

    1999-07-01

    The study reported here demonstrates the feasibility of presenting cognitive tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) to either marmosets or rhesus monkeys in their home cages. This location of testing offers opportunities for the measurement of additional indices, for example spontaneous behaviour (Prowse et al. 1995) and electrophysiology (Pearce et al. 1998) as well as facilitating repeated test presentation. Results from 12 marmosets and 4 rhesus monkeys which have completed several sequences of an eight-stage discrimination task involving simple discriminations, compound discriminations and reversals are reported. The paradigm developed has application in long-term studies. Tests from CANTAB have been used extensively in normal humans (Robbins et al. 1994) as well as a range of patient groups (Owen et al. 1992, Elliott et al. 1995) and to assess drug effects (Coull et al. 1996). Additionally some of these tests have been presented to marmosets (Roberts et al. 1988) to examine neuropsychological functioning. This comparative approach facilitates meaningful cross species comparison, particularly in the study of the effects of pharmacological intervention.

  1. Resequencing of the common marmoset genome improves genome assemblies and gene-coding sequence analysis.

    PubMed

    Sato, Kengo; Kuroki, Yoko; Kumita, Wakako; Fujiyama, Asao; Toyoda, Atsushi; Kawai, Jun; Iriki, Atsushi; Sasaki, Erika; Okano, Hideyuki; Sakakibara, Yasubumi

    2015-11-20

    The first draft of the common marmoset (Callithrix jacchus) genome was published by the Marmoset Genome Sequencing and Analysis Consortium. The draft was based on whole-genome shotgun sequencing, and the current assembly version is Callithrix_jacches-3.2.1, but there still exist 187,214 undetermined gap regions and supercontigs and relatively short contigs that are unmapped to chromosomes in the draft genome. We performed resequencing and assembly of the genome of common marmoset by deep sequencing with high-throughput sequencing technology. Several different sequence runs using Illumina sequencing platforms were executed, and 181 Gbp of high-quality bases including mate-pairs with long insert lengths of 3, 8, 20, and 40 Kbp were obtained, that is, approximately 60× coverage. The resequencing significantly improved the MGSAC draft genome sequence. The N50 of the contigs, which is a statistical measure used to evaluate assembly quality, doubled. As a result, 51% of the contigs (total length: 299 Mbp) that were unmapped to chromosomes in the MGSAC draft were merged with chromosomal contigs, and the improved genome sequence helped to detect 5,288 new genes that are homologous to human cDNAs and the gaps in 5,187 transcripts of the Ensembl gene annotations were completely filled.

  2. Marmoset induced pluripotent stem cells: Robust neural differentiation following pretreatment with dimethyl sulfoxide.

    PubMed

    Qiu, Zhifang; Mishra, Anuja; Li, Miao; Farnsworth, Steven L; Guerra, Bernadette; Lanford, Robert E; Hornsby, Peter J

    2015-07-01

    The marmoset is an important nonhuman primate model for regenerative medicine. For experimental autologous cell therapy based on induced pluripotent (iPS) cells in the marmoset, cells must be able to undergo robust and reliable directed differentiation that will not require customization for each specific iPS cell clone. When marmoset iPS cells were aggregated in a hanging drop format for 3 days, followed by exposure to dual SMAD inhibitors and retinoic acid in monolayer culture for 3 days, we found substantial variability in the response of different iPS cell clones. However, when clones were pretreated with 0.05-2% dimethyl sulfoxide (DMSO) for 24 hours, all clones showed a very similar maximal response to the directed differentiation scheme. Peak responses were observed at 0.5% DMSO in two clones and at 1% DMSO in a third clone. When patterns of gene expression were examined by microarray analysis, hierarchical clustering showed very similar responses in all 3 clones when they were pretreated with optimal DMSO concentrations. The change in phenotype following exposure to DMSO and the 6 day hanging drop/monolayer treatment was confirmed by immunocytochemistry. Analysis of DNA content in DMSO-exposed cells indicated that it is unlikely that DMSO acts by causing cells to exit from the cell cycle. This approach should be generally valuable in the directed neural differentiation of pluripotent cells for experimental cell therapy. PMID:26070112

  3. Characterization of mammary epithelial stem/progenitor cells and their changes with aging in common marmosets.

    PubMed

    Wu, Anqi; Dong, Qiaoxiang; Gao, Hui; Shi, Yuanshuo; Chen, Yuanhong; Zhang, Fuchuang; Bandyopadhyay, Abhik; Wang, Danhan; Gorena, Karla M; Huang, Changjiang; Tardif, Suzette; Nathanielsz, Peter W; Sun, Lu-Zhe

    2016-01-01

    Age is the number one risk factor for breast cancer, yet the underlying mechanisms are unexplored. Age-associated mammary stem cell (MaSC) dysfunction is thought to play an important role in breast cancer carcinogenesis. Non-human primates with their close phylogenetic relationship to humans provide a powerful model system to study the effects of aging on human MaSC. In particular, the common marmoset monkey (Callithrix jacchus) with a relatively short life span is an ideal model for aging research. In the present study, we characterized for the first time the mammary epithelial stem/progenitor cells in the common marmoset. The MaSC-enriched cells formed four major types of morphologically distinct colonies when cultured on plates pre-seeded with irradiated NIH3T3 fibroblasts, and were also capable of forming mammospheres in suspension culture and subsequent formation of 3D organoids in Matrigel culture. Most importantly, these 3D organoids were found to contain stem/progenitor cells that can undergo self-renewal and multi-lineage differentiation both in vitro and in vivo. We also observed a significant decrease of luminal-restricted progenitors with age. Our findings demonstrate that common marmoset mammary stem/progenitor cells can be isolated and quantified with established in vitro and in vivo assays used for mouse and human studies. PMID:27558284

  4. Functional columns in superior temporal sulcus areas of the common marmoset.

    PubMed

    Suzuki, Wataru; Tani, Toshiki; Banno, Taku; Miyakawa, Naohisa; Abe, Hiroshi; Ichinohe, Noritaka

    2015-12-16

    Cortical areas in the superior temporal sulcus (STS) of primates have been recognized as a part of the 'social brain'. In particular, biological motion stimuli elicit neuronal responses in the STS, indicating their roles in the ability to understand others' actions. However, the spatial organization of functionally identified STS cells is not well understood because it is difficult to identify the precise locations of cells in sulcal regions. Here, using a small New World monkey, the common marmoset (Callithrix jacchus) that has a lissencephalic brain, we investigated the spatial organization of the cells responsive to other's actions in STS. The neural responses to movies showing several types of other's actions were recorded with multicontact linear-array electrodes that had four shanks (0.4 mm spacing), with eight electrode contacts (0.2 mm spacing) for each shank. The four shanks were penetrated perpendicular to the cortical surface. We found that STS cells significantly responded to other's goal-directed actions, such as when an actor marmoset was reaching for and grasping a piece of food. The response profiles to the movies were more similar between the vertically positioned electrodes than horizontally positioned electrodes when the distances between electrodes were matched. This indicates that there are functional columns in the higher-order visual areas in STS of the common marmoset. PMID:26512934

  5. Behavioral and trait rating assessments of personality in common marmosets (Callithrix jacchus).

    PubMed

    Iwanicki, Suzanne; Lehmann, Julia

    2015-08-01

    The study of personality in animals is a rapidly growing scientific field and numerous species have been reported to show consistent personality profiles. Much animal personality research has focused on nonhuman primates, with the main emphasis being placed on Old World primates, particularly rhesus macaques and chimpanzees. So far, little work has been done on cooperatively breeding nonhuman primates and New World species. Here, we study personality in the cooperatively breeding common marmosets (Callithrix jacchus) to broaden the taxonomic range of such research and to widen the perspective of comparative personality research. We use behavioral data collection and observer trait ratings to assess marmoset personality dimensions. The resulting behavioral and rating-derived personality dimensions, when viewed in tandem, resemble the human five-factor model and include extraversion, agreeableness, neuroticism, openness, and conscientiousness. Correlations between the behavioral data and the observer trait-rated personality components suggest that the personality construct of common marmosets exhibits both convergent and discriminant validity. The finding of a distinct Conscientiousness component in this species extends previous knowledge in comparative personality psychology and warrants reconsideration of proposed taxonomic trait distributions.

  6. Characterization of mammary epithelial stem/progenitor cells and their changes with aging in common marmosets

    PubMed Central

    Wu, Anqi; Dong, Qiaoxiang; Gao, Hui; Shi, Yuanshuo; Chen, Yuanhong; Zhang, Fuchuang; Bandyopadhyay, Abhik; Wang, Danhan; Gorena, Karla M.; Huang, Changjiang; Tardif, Suzette; Nathanielsz, Peter W.; Sun, Lu-Zhe

    2016-01-01

    Age is the number one risk factor for breast cancer, yet the underlying mechanisms are unexplored. Age-associated mammary stem cell (MaSC) dysfunction is thought to play an important role in breast cancer carcinogenesis. Non-human primates with their close phylogenetic relationship to humans provide a powerful model system to study the effects of aging on human MaSC. In particular, the common marmoset monkey (Callithrix jacchus) with a relatively short life span is an ideal model for aging research. In the present study, we characterized for the first time the mammary epithelial stem/progenitor cells in the common marmoset. The MaSC-enriched cells formed four major types of morphologically distinct colonies when cultured on plates pre-seeded with irradiated NIH3T3 fibroblasts, and were also capable of forming mammospheres in suspension culture and subsequent formation of 3D organoids in Matrigel culture. Most importantly, these 3D organoids were found to contain stem/progenitor cells that can undergo self-renewal and multi-lineage differentiation both in vitro and in vivo. We also observed a significant decrease of luminal-restricted progenitors with age. Our findings demonstrate that common marmoset mammary stem/progenitor cells can be isolated and quantified with established in vitro and in vivo assays used for mouse and human studies. PMID:27558284

  7. Presence of Viral Genome in Urine and Development of Hematuria and Pathological Changes in Kidneys in Common Marmoset (Callithrix jacchus) after Inoculation with Dengue Virus

    PubMed Central

    Moi, Meng Ling; Omatsu, Tsutomu; Hirayama, Takanori; Nakamura, Shinichiro; Katakai, Yuko; Yoshida, Tomoyuki; Saito, Akatsuki; Tajima, Shigeru; Ito, Mikako; Takasaki, Tomohiko; Akari, Hirofumi; Kurane, Ichiro

    2013-01-01

    Common marmosets (Callithrix jacchus) developed high levels of viremia, clinical signs including fever, weight loss, a decrease in activity and hematuria upon inoculation with dengue virus (DENV). Presence of DENV genome in urine samples and pathological changes in kidneys were examined in the present study. Levels of DENV genome were determined in 228 urine samples from 20 primary DENV-inoculated marmosets and in 56 urine samples from four secondary DENV-inoculated marmosets. DENV genome was detected in 75% (15/20) of marmosets after primary DENV infection. No DENV genome was detected in urine samples from the marmosets with secondary infection with homologous DENV (0%, 0/4). Two marmosets demonstrated hematuria. Pathological analysis of the kidneys demonstrated non-suppressive interstitial nephritis with renal tubular regeneration. DENV antigen-positive cells were detected in kidneys. In human dengue virus infections, some patients present renal symptoms. The results indicate that marmosets recapitulate some aspects of the involvement of kidneys in human DENV infection, and suggest that marmosets are potentially useful for the studies of the pathogenesis of DENV infection, including kidneys. PMID:25437039

  8. Modeling the Minimal Newborn's Intersubjective Mind: The Visuotopic-Somatotopic Alignment Hypothesis in the Superior Colliculus

    PubMed Central

    Pitti, Alexandre; Kuniyoshi, Yasuo; Quoy, Mathias; Gaussier, Philippe

    2013-01-01

    The question whether newborns possess inborn social skills is a long debate in developmental psychology. Fetal behavioral and anatomical observations show evidences for the control of eye movements and facial behaviors during the third trimester of pregnancy whereas specific sub-cortical areas, like the superior colliculus (SC) and the striatum appear to be functionally mature to support these behaviors. These observations suggest that the newborn is potentially mature for developing minimal social skills. In this manuscript, we propose that the mechanism of sensory alignment observed in SC is particularly important for enabling the social skills observed at birth such as facial preference and facial mimicry. In a computational simulation of the maturing superior colliculus connected to a simulated facial tissue of a fetus, we model how the incoming tactile information is used to direct visual attention toward faces. We suggest that the unisensory superficial visual layer (eye-centered) and the deep somatopic layer (face-centered) in SC are combined into an intermediate layer for visuo-tactile integration and that multimodal alignment in this third layer allows newborns to have a sensitivity to configuration of eyes and mouth. We show that the visual and tactile maps align through a Hebbian learning stage and and strengthen their synaptic links from each other into the intermediate layer. It results that the global network produces some emergent properties such as sensitivity toward the spatial configuration of face-like patterns and the detection of eyes and mouth movement. PMID:23922718

  9. Spatial synchronization of visual stimulus-evoked gamma frequency oscillations in the rat superior colliculus.

    PubMed

    Baranauskas, Gytis; Svirskis, Gytis; Tkatch, Tatiana

    2016-02-10

    In the superior colliculus, visual stimuli can induce gamma frequency oscillations of neuronal activity. It has been shown that in cats, these oscillations are synchronized over distances of greater than 300 μm that may contribute toward visual information processing. We investigated the spatial properties of such oscillations in a rodent because the availability of molecular tools could enable future studies on the role of these oscillations in visual information processing. Using extracellular electrode array recordings in anesthetized rats, we found that visual stimuli-induced gamma and eta frequency (30-115 Hz) oscillations of the local field potential that were synchronized over distances of ∼ 600 μm. Multiple-unit events were phase locked to the local field potential signal and showed prominent oscillations during OFF responses. The rate of lower than 5 ms cross-electrode coincidences was in line with the response-corrected predictions for each electrode. These data suggest that the synchronized superior colliculus neuronal activity is largely network driven, whereas common synaptic inputs play a minor role. PMID:26735701

  10. Visual receptive field properties of neurons in the superficial superior colliculus of the mouse.

    PubMed

    Wang, Lupeng; Sarnaik, Rashmi; Rangarajan, Krsna; Liu, Xiaorong; Cang, Jianhua

    2010-12-01

    The mouse is a promising model in the study of visual system function and development because of available genetic tools. However, a quantitative analysis of visual receptive field properties had not been performed in the mouse superior colliculus (SC) despite its importance in mouse vision and its usefulness in developmental studies. We have made single-unit extracellular recordings from superficial layers of the SC in urethane-anesthetized C57BL/6 mice. We first map receptive fields with flashing spot stimuli and show that most SC neurons have spatially overlapped ON and OFF subfields. With drifting sinusoidal gratings, we then determine the tuning properties of individual SC neurons, including selectivity for stimulus direction and orientation, spatial frequency tuning, temporal frequency tuning, response linearity, and size preference. A wide range of receptive field sizes and selectivity are observed across the population and in various subtypes of SC neurons identified morphologically. In particular, orientation-selective responses are discovered in the mouse SC, and they are not affected by cortical lesion or long-term visual deprivation. However, ON/OFF characteristics and spatial frequency tuning of SC neurons are influenced by cortical inputs and require visual experience during development. Together, our results provide essential information for future investigations on the functional development of the superior colliculus. PMID:21147997

  11. External rotation views in the diagnosis of posterior colliculus fracture of the medial malleolus.

    PubMed

    Ebraheim, N A; Wong, F Y

    1996-05-01

    A 25-year-old white man sustained a fracture dislocation of the right ankle with a displaced fracture of the lateral malleolus while playing basketball. He also sustained a fracture of the medial aspect of the distal tibia, in addition to an apparent deltoid ligament injury. The patient underwent open reduction and internal fixation of the lateral malleolus and insertion of a syndesmotic screw. Intraoperatively, external rotation radiographs of the ankle were obtained to determine the origin of the fracture of the medial side of the ankle joint. The radiographs clearly showed a minimally displaced fracture of the posterior colliculus. Posterior colliculus fracture can be occult. This fracture may not be clearly visible on plain antero-posterior or mortise-view radiographs and external rotation is necessary for its diagnosis. This fracture is usually minimally displaced and can be satisfactorily treated conservatively. The patient's leg was placed in a short-leg cast for 6 weeks. Follow-up radiographs revealed healing of the fracture.

  12. Inferior vena caval masses identified by echocardiography

    NASA Technical Reports Server (NTRS)

    Sun, J. P.; Asher, C. R.; Xu, Y.; Huang, V.; Griffin, B. P.; Stewart, W. J.; Novick, A. C.; Thomas, J. D.

    1999-01-01

    The most common cause of an inferior vena caval mass is renal cell carcinoma that extends through the lumen, occurring in 47 of 62 patients (85%). Detection of an inferior vena caval mass affects the surgical approach requiring cardiopulmonary bypass for resection when the mass extends to the heart.

  13. Neuroanatomical approaches of the tectum-reticular pathways and immunohistochemical evidence for serotonin-positive perikarya on neuronal substrates of the superior colliculus and periaqueductal gray matter involved in the elaboration of the defensive behavior and fear-induced analgesia.

    PubMed

    Coimbra, N C; De Oliveira, R; Freitas, R L; Ribeiro, S J; Borelli, K G; Pacagnella, R C; Moreira, J E; da Silva, L A; Melo, L L; Lunardi, L O; Brandão, M L

    2006-01-01

    Deep layers of the superior colliculus, the dorsal periaqueductal gray matter and the inferior colliculus are midbrain structures involved in the generation of defensive behavior and fear-induced anti-nociception. Local injections of the GABA(A) antagonist bicuculline into these structures have been used to produce this defense reaction. Serotonin is thought to be the main neurotransmitter to modulate such defense reaction in mammals. This study is the first attempt to employ immunohistochemical techniques to locate serotonergic cells in the same midbrain sites from where defense reaction is evoked by chemical stimulation with bicuculline. The blockade of GABA(A) receptors in the neural substrates of the dorsal mesencephalon was followed by vigorous defensive reactions and increased nociceptive thresholds. Light microscopy immunocytochemistry with streptavidin method was used for the localization of the putative cells of defensive behavior with antibodies to serotonin in the rat's midbrain. Neurons positive to serotonin were found in the midbrain sites where defensive reactions were evoked by microinjection of bicuculline. Serotonin was localized to somata and projections of the neural networks of the mesencephalic tectum. Immunohistochemical studies showed that the sites in which neuronal perikarya positive to serotonin were identified in intermediate and deep layers of the superior colliculus, and in the dorsal and ventral columns of the periaqueductal gray matter are the same which were activated during the generation of defense behaviors, such as alertness, freezing, and escape reactions, induced by bicuculline. These findings support the contention that serotonin and GABAergic neurons may act in concert in the modulation of defense reaction in the midbrain tectum. Our neuroanatomical findings indicate a direct neural pathway connecting the dorsal midbrain and monoaminergic nuclei of the descending pain inhibitory system, with profuse synaptic terminals mainly

  14. Corticospinal Tract Tracing in the Marmoset with a Clinical Whole-Body 3T Scanner Using Manganese-Enhanced MRI

    PubMed Central

    Plas, Benjamin; Bolan, Faye; Boulanouar, Kader; Renaud, Luc; Darmana, Robert; Vaysse, Laurence; Vieu, Christophe; Loubinoux, Isabelle

    2015-01-01

    Manganese-enhanced MRI (MEMRI) has been described as a powerful tool to depict the architecture of neuronal circuits. In this study we investigated the potential use of in vivo MRI detection of manganese for tracing neuronal projections from the primary motor cortex (M1) in healthy marmosets (Callithrix Jacchus). We determined the optimal dose of manganese chloride (MnCl2) among 800, 400, 40 and 8nmol that led to manganese-induced hyperintensity furthest from the injection site, as specific to the corticospinal tract as possible, and that would not induce motor deficit. A commonly available 3T human clinical MRI scanner and human knee coil were used to follow hyperintensity in the corticospinal tract 24h after injection. A statistical parametric map of seven marmosets injected with the chosen dose, 8 nmol, showed the corticospinal tract and M1 connectivity with the basal ganglia, substantia nigra and thalamus. Safety was determined for the lowest dose that did not induce dexterity and grip strength deficit, and no behavioral effects could be seen in marmosets who received multiple injections of manganese one month apart. In conclusion, our study shows for the first time in marmosets, a reliable and reproducible way to perform longitudinal ME-MRI experiments to observe the integrity of the marmoset corticospinal tract on a clinical 3T MRI scanner. PMID:26398500

  15. Corticospinal Tract Tracing in the Marmoset with a Clinical Whole-Body 3T Scanner Using Manganese-Enhanced MRI.

    PubMed

    Demain, Boris; Davoust, Carole; Plas, Benjamin; Bolan, Faye; Boulanouar, Kader; Renaud, Luc; Darmana, Robert; Vaysse, Laurence; Vieu, Christophe; Loubinoux, Isabelle

    2015-01-01

    Manganese-enhanced MRI (MEMRI) has been described as a powerful tool to depict the architecture of neuronal circuits. In this study we investigated the potential use of in vivo MRI detection of manganese for tracing neuronal projections from the primary motor cortex (M1) in healthy marmosets (Callithrix Jacchus). We determined the optimal dose of manganese chloride (MnCl2) among 800, 400, 40 and 8 nmol that led to manganese-induced hyperintensity furthest from the injection site, as specific to the corticospinal tract as possible, and that would not induce motor deficit. A commonly available 3T human clinical MRI scanner and human knee coil were used to follow hyperintensity in the corticospinal tract 24h after injection. A statistical parametric map of seven marmosets injected with the chosen dose, 8 nmol, showed the corticospinal tract and M1 connectivity with the basal ganglia, substantia nigra and thalamus. Safety was determined for the lowest dose that did not induce dexterity and grip strength deficit, and no behavioral effects could be seen in marmosets who received multiple injections of manganese one month apart. In conclusion, our study shows for the first time in marmosets, a reliable and reproducible way to perform longitudinal ME-MRI experiments to observe the integrity of the marmoset corticospinal tract on a clinical 3T MRI scanner.

  16. Five-sixth Nephrectomy in Female Common Marmosets(Callithrix jacchus) as a Chronic Renal Failure Model

    PubMed Central

    Yamaguchi, Itaru; Myojo, Kensuke; Sanada, Hiroko; Takami, Atsuko; Suzuki, Yui; Imaizumi, Minami; Takada, Chie; Kimoto, Naoya; Saeki, Koji; Yamate, Jyoji; Takaba, Katsumi

    2014-01-01

    To assess the relevance and availability of subtotal nephrectomized common marmoset monkeys as a chronic renal failure (CRF) model, we observed for 26 weeks the pathophysiological condition of female marmosets subjected to five-sixth surgical nephrectomy (5/6Nx) by a two-step surgical method. The 5/6Nx marmosets showed a significant increase in serum levels of urea nitrogen, creatinine and cystatin-C immediately after 5/6Nx surgery. These renal disorder parameters subsequently tended to decrease with the passage of time but remained higher than the control levels by the end of the study. Hyperplastic parathyroid glands, a high turnover state of osteodystrophy in the femoral bone with higher serum ALP activity and anemia with hypocellularity of bone marrow were evident. The 5/6Nx marmosets showed a stable CRF condition for a long time and some characteristic disorders similar to those observed in CRF patients. These diagnostic aspects might be a species-specific anatomical and physiological signature, reflecting the nutritional condition. The CRF model using 5/6Nx marmosets might become a useful method of evaluating the unique mechanism of CRF development. PMID:25378803

  17. Bilateral inferior petrosal sinus sampling.

    PubMed

    Zampetti, Benedetta; Grossrubatscher, Erika; Dalino Ciaramella, Paolo; Boccardi, Edoardo; Loli, Paola

    2016-07-01

    Simultaneous bilateral inferior petrosal sinus sampling (BIPSS) plays a crucial role in the diagnostic work-up of Cushing's syndrome. It is the most accurate procedure in the differential diagnosis of hypercortisolism of pituitary or ectopic origin, as compared with clinical, biochemical and imaging analyses, with a sensitivity and specificity of 88-100% and 67-100%, respectively. In the setting of hypercortisolemia, ACTH levels obtained from venous drainage of the pituitary are expected to be higher than the levels of peripheral blood, thus suggesting pituitary ACTH excess as the cause of hypercortisolism. Direct stimulation of the pituitary corticotroph with corticotrophin-releasing hormone enhances the sensitivity of the procedure. The procedure must be undertaken in the presence of hypercortisolemia, which suppresses both the basal and stimulated secretory activity of normal corticotrophic cells: ACTH measured in the sinus is, therefore, the result of the secretory activity of the tumor tissue. The poor accuracy in lateralization of BIPSS (positive predictive value of 50-70%) makes interpetrosal ACTH gradient alone not sufficient for the localization of the tumor. An accurate exploration of the gland is recommended if a tumor is not found in the predicted area. Despite the fact that BIPSS is an invasive procedure, the occurrence of adverse events is extremely rare, particularly if it is performed by experienced operators in referral centres. PMID:27352844

  18. Bilateral inferior petrosal sinus sampling.

    PubMed

    Zampetti, Benedetta; Grossrubatscher, Erika; Dalino Ciaramella, Paolo; Boccardi, Edoardo; Loli, Paola

    2016-07-01

    Simultaneous bilateral inferior petrosal sinus sampling (BIPSS) plays a crucial role in the diagnostic work-up of Cushing's syndrome. It is the most accurate procedure in the differential diagnosis of hypercortisolism of pituitary or ectopic origin, as compared with clinical, biochemical and imaging analyses, with a sensitivity and specificity of 88-100% and 67-100%, respectively. In the setting of hypercortisolemia, ACTH levels obtained from venous drainage of the pituitary are expected to be higher than the levels of peripheral blood, thus suggesting pituitary ACTH excess as the cause of hypercortisolism. Direct stimulation of the pituitary corticotroph with corticotrophin-releasing hormone enhances the sensitivity of the procedure. The procedure must be undertaken in the presence of hypercortisolemia, which suppresses both the basal and stimulated secretory activity of normal corticotrophic cells: ACTH measured in the sinus is, therefore, the result of the secretory activity of the tumor tissue. The poor accuracy in lateralization of BIPSS (positive predictive value of 50-70%) makes interpetrosal ACTH gradient alone not sufficient for the localization of the tumor. An accurate exploration of the gland is recommended if a tumor is not found in the predicted area. Despite the fact that BIPSS is an invasive procedure, the occurrence of adverse events is extremely rare, particularly if it is performed by experienced operators in referral centres.

  19. Bilateral inferior petrosal sinus sampling

    PubMed Central

    Grossrubatscher, Erika; Dalino Ciaramella, Paolo; Boccardi, Edoardo

    2016-01-01

    Simultaneous bilateral inferior petrosal sinus sampling (BIPSS) plays a crucial role in the diagnostic work-up of Cushing’s syndrome. It is the most accurate procedure in the differential diagnosis of hypercortisolism of pituitary or ectopic origin, as compared with clinical, biochemical and imaging analyses, with a sensitivity and specificity of 88–100% and 67–100%, respectively. In the setting of hypercortisolemia, ACTH levels obtained from venous drainage of the pituitary are expected to be higher than the levels of peripheral blood, thus suggesting pituitary ACTH excess as the cause of hypercortisolism. Direct stimulation of the pituitary corticotroph with corticotrophin-releasing hormone enhances the sensitivity of the procedure. The procedure must be undertaken in the presence of hypercortisolemia, which suppresses both the basal and stimulated secretory activity of normal corticotrophic cells: ACTH measured in the sinus is, therefore, the result of the secretory activity of the tumor tissue. The poor accuracy in lateralization of BIPSS (positive predictive value of 50–70%) makes interpetrosal ACTH gradient alone not sufficient for the localization of the tumor. An accurate exploration of the gland is recommended if a tumor is not found in the predicted area. Despite the fact that BIPSS is an invasive procedure, the occurrence of adverse events is extremely rare, particularly if it is performed by experienced operators in referral centres. PMID:27352844

  20. Inferior alveolar nerve block: Alternative technique

    PubMed Central

    Thangavelu, K.; Kannan, R.; Kumar, N. Senthil

    2012-01-01

    Background: Inferior alveolar nerve block (IANB) is a technique of dental anesthesia, used to produce anesthesia of the mandibular teeth, gingivae of the mandible and lower lip. The conventional IANB is the most commonly used the nerve block technique for achieving local anesthesia for mandibular surgical procedures. In certain cases, however, this nerve block fails, even when performed by the most experienced clinician. Therefore, it would be advantageous to find an alternative simple technique. Aim and Objective: The objective of this study is to find an alternative inferior alveolar nerve block that has a higher success rate than other routine techniques. To this purpose, a simple painless inferior alveolar nerve block was designed to anesthetize the inferior alveolar nerve. Materials and Methods: This study was conducted in Oral surgery department of Vinayaka Mission's dental college Salem from May 2009 to May 2011. Five hundred patients between the age of 20 years and 65 years who required extraction of teeth in mandible were included in the study. Out of 500 patients 270 were males and 230 were females. The effectiveness of the IANB was evaluated by using a sharp dental explorer in the regions innervated by the inferior alveolar, lingual, and buccal nerves after 3, 5, and 7 min, respectively. Conclusion: This study concludes that inferior alveolar nerve block is an appropriate alternative nerve block to anesthetize inferior alveolar nerve due to its several advantages. PMID:25885503

  1. Oxytocin facilitates fidelity in well-established marmoset pairs by reducing sociosexual behavior toward opposite-sex strangers

    PubMed Central

    Cavanaugh, Jon; Mustoe, Aaryn C.; Taylor, Jack H.; French, Jeffrey A.

    2014-01-01

    Summary Behavioral strategies that facilitate the maintenance of social bonds are critical for the preservation of high-quality social relationships. Central oxytocin (OT) activity modulates the behavioral features of socially monogamous relationships in a number of mammalian species (including marmoset monkeys), and plays a vital role in the behavioral maintenance of long-term social relationships. Two distinct variants of OT have been identified in some New World primates (including marmosets; Lee et al., 2011). The marmoset variant of the oxytocin ligand (Pro8-OT) is structurally distinct from the consensus mammalian variant of the oxytocin ligand (Leu8-OT), due to a proline substitution at the 8th amino-acid position. The goal of the present study was to determine if treating marmosets with Pro8-OT, relative to treatments with Leu8-OT, control saline, or an OT antagonist, had modulatory effects on the behavioral maintenance of long-term social relationships in marmosets. Treatment with the Pro8 variant, but not the Leu8 variant, of OT facilitated fidelity with a long-term partner by reducing time spent in close proximity with an opposite-sex stranger. However, this facilitative effect of Pro8-OT on proximity behavior manifested itself differently in male and female marmosets, such that females preferred to interact socially with their partner rather than a stranger when treated with Pro8-OT, while males spent less time in close proximity with both their partner and a stranger when treated with Pro8-OT. Furthermore, treatment with Pro8-OT, but not Leu8-OT, significantly delayed the expression of sexual solicitation behavior toward an opposite-sex stranger in both male and female marmosets, but had no effect on sociosexual behavior directed toward a long-term partner. These results suggest that the OT system is highly involved in reducing fidelity-threatening behaviors in well-established marmoset pairs, and that the effects were only produced by species

  2. Neurons and glia in cat superior colliculus accumulate [3H]gamma-aminobutyric acid (GABA).

    PubMed

    Mize, R R; Spencer, R F; Sterling, P

    1981-11-01

    We have examined by autoradiography the labeling pattern in the cat superior colliculus following injection of tritiated gamma-aminobutyric acid (GABA). Silver grains were heavily distributed within the zonal layer and the upper 200 micrometer of the superficial gray. Fewer grains were observed deeper within the superficial gray, and still fewer were found within the optic and intermediate gray layers. The accumulation of label was restricted to certain classes of neuron and glia. Densely labeled neurons were small (8-12 micrometer in diameter) and located primarily within the upper 200 micrometer. Dark oligodendrocytes and astrocytes showed a moderate accumulation of label while pale oligodendrocytes and microglia were unlabeled. Label was also selectively accumulated over several other types of profile within the neuropil, including presynaptic dendrites, axons, and axon terminals.

  3. Role of the superior colliculus in choosing mixed-strategy saccades.

    PubMed

    Thevarajah, Dhushan; Mikulić, Areh; Dorris, Michael C

    2009-02-18

    Game theory outlines optimal response strategies during mixed-strategy competitions. The neural processes involved in choosing individual strategic actions, however, remain poorly understood. Here, we tested whether the superior colliculus (SC), a brain region critical for generating sensory-guided saccades, is also involved in choosing saccades under strategic conditions. Monkeys were free to choose either of two saccade targets as they competed against a computer opponent during the mixed-strategy game "matching pennies." The accuracy with which presaccadic SC activity predicted upcoming choice gradually increased in the time leading up to the saccade. Probing the SC with suprathreshold stimulation demonstrated that these evolving signals were functionally involved in preparing strategic saccades. Finally, subthreshold stimulation of the SC increased the likelihood that contralateral saccades were selected. Together, our results suggest that motor regions of the brain play an active role in choosing strategic actions rather than passively executing those prespecified by upstream executive regions.

  4. Reduction of glutamate content in rat superior colliculus after retino-tectal denervation.

    PubMed

    Sakurai, T; Miyamoto, T; Okada, Y

    1990-02-16

    The effect of afferent lesions on glutamate content was measured in the lamina of the superior colliculus (SC) in the rat. The analysis was performed 12 days after unilateral enucleation (left eye), or ablation of visual cortex (right), or both enucleation and ablation. The glutamate contained in the superficial grey layer (SGL) and deep layer was measured in the sectioned freeze-dried sample using an enzymatic cycling method of NAD-NADH. The upper layer of SGL contralateral to enucleation exhibited a significant reduction (23%) in glutamate content. Combining enucleation and ablation further decreased (35%) glutamate content. Additionally, the synaptic potential evoked in the SGL of SC slices after stimulation of optic layer was blocked by the application of kynurenic acid (3 mM) or DNQX (30 microM). These results indicate that the retino-tectal pathway in the rat can be glutamatergic in nature.

  5. Patterns on serpentine shapes elicit visual attention in marmosets (Callithrix jacchus).

    PubMed

    Wombolt, Jessica R; Caine, Nancy G

    2016-09-01

    Given the prevalence of threatening snakes in the evolutionary history, and modern-day environments of human and nonhuman primates, sensory, and perceptual abilities that allow for quick detection of, and appropriate response to snakes are likely to have evolved. Many studies have demonstrated that primates recognize snakes faster than other stimuli, and it is suggested that the unique serpentine shape is responsible for its quick detection. However, there are many nonthreatening serpentine shapes in the environment (e.g., vines) that are not threatening; therefore, other cues must be used to distinguish threatening from benign serpentine objects. In two experiments, we systematically evaluated how common marmosets (Callithrix jacchus) visually attend to specific snake-like features. In the first experiment, we examined if skin pattern is a cue that elicits increased visual inspection of serpentine shapes by measuring the amount of time the marmosets looked into a blind before, during, and after presentation of clay models with and without patterns. The marmosets spent the most time looking at the objects, both serpentine and triangle, that were etched with scales, suggesting that something may be uniquely salient about scales in evoking attention. In contrast, they showed relatively little interest in the unpatterned serpentine and control (a triangle) stimuli. In experiment 2, we replicated and extended the results of experiment 1 by adding additional stimulus conditions. We found that patterns on a serpentine shape generated more inspection than those same patterns on a triangle shape. We were unable to confirm that a scaled pattern is unique in its ability to elicit visual interest; the scaled models elicited similar looking times as line and star patterns. Our data provide a foundation for future research to examine how snakes are detected and identified by primates. Am. J. Primatol. 78:928-936, 2016. © 2016 Wiley Periodicals, Inc. PMID:27225979

  6. Effects of support diameter and compliance on common marmoset (Callithrix jacchus) gait kinematics.

    PubMed

    Young, Jesse W; Stricklen, Bethany M; Chadwell, Brad A

    2016-09-01

    Locomotion is precarious in an arboreal habitat, where supports can vary in both diameter and level of compliance. Several previous studies have evaluated the influence of substrate diameter on the locomotor performance of arboreal quadrupeds. The influence of substrate compliance, however, has been mostly unexamined. Here, we used a multifactorial experimental design to investigate how perturbations in both diameter and compliance affect the gait kinematics of marmosets (Callithrix jacchus; N=2) moving over simulated arboreal substrates. We used 3D-calibrated video to quantify marmoset locomotion over a horizontal trackway consisting of variably sized poles (5, 2.5 and 1.25 cm in diameter), analyzing a total of 120 strides. The central portion of the trackway was either immobile or mounted on compliant foam blocks, depending on condition. We found that narrowing diameter and increasing compliance were both associated with relatively longer substrate contact durations, though adjustments to diameter were often inconsistent relative to compliance-related adjustments. Marmosets also responded to narrowing diameter by reducing speed, flattening center of mass (CoM) movements and dampening support displacement on the compliant substrate. For the subset of strides on the compliant support, we found that speed, contact duration and CoM amplitude explained >60% of the variation in substrate displacement over a stride, suggesting a direct performance advantage to these kinematic adjustments. Overall, our results show that compliant substrates can exert a significant influence on gait kinematics. Substrate compliance, and not just support diameter, should be considered a critical environmental variable when evaluating locomotor performance in arboreal quadrupeds. PMID:27582562

  7. The effect of habitat acoustics on common marmoset vocal signal transmission.

    PubMed

    Morrill, Ryan J; Thomas, A Wren; Schiel, Nicola; Souto, Antonio; Miller, Cory T

    2013-09-01

    Noisy acoustic environments present several challenges for the evolution of acoustic communication systems. Among the most significant is the need to limit degradation of spectro-temporal signal structure in order to maintain communicative efficacy. This can be achieved by selecting for several potentially complementary processes. Selection can act on behavioral mechanisms permitting signalers to control the timing and occurrence of signal production to avoid acoustic interference. Likewise, the signal itself may be the target of selection, biasing the evolution of its structure to comprise acoustic features that avoid interference from ambient noise or degrade minimally in the habitat. Here, we address the latter topic for common marmoset (Callithrix jacchus) long-distance contact vocalizations, known as phee calls. Our aim was to test whether this vocalization is specifically adapted for transmission in a species-typical forest habitat, the Atlantic forests of northeastern Brazil. We combined seasonal analyses of ambient habitat acoustics with experiments in which pure tones, clicks, and vocalizations were broadcast and rerecorded at different distances to characterize signal degradation in the habitat. Ambient sound was analyzed from intervals throughout the day and over rainy and dry seasons, showing temporal regularities across varied timescales. Broadcast experiment results indicated that the tone and click stimuli showed the typically inverse relationship between frequency and signaling efficacy. Although marmoset phee calls degraded over distance with marked predictability compared with artificial sounds, they did not otherwise appear to be specially designed for increased transmission efficacy or minimal interference in this habitat. We discuss these data in the context of other similar studies and evidence of potential behavioral mechanisms for avoiding acoustic interference in order to maintain effective vocal communication in common marmosets.

  8. Circadian activity rhythm in pre-pubertal and pubertal marmosets (Callithrix jacchus) living in family groups.

    PubMed

    Melo, Paula R; Gonçalves, Bruno S B; Menezes, Alexandre A L; Azevedo, Carolina V M

    2016-03-01

    In marmosets, a phase advance was observed in activity onset in pubertal animals living in captivity under semi-natural conditions which had stronger correlation with the times of sunrise over the course of the year than the age of the animal. In order to evaluate the effect of puberty on the circadian activity rhythm in male and female marmosets living in family groups in controlled lighting conditions, the activity of 5 dyads of twins (4 ♀/♂ and 1 ♂/♂) and their respective parents was continuously monitored by actiwatches between the 4th and 12th months of age. The families were kept under LD 12:12 h with constant humidity and temperature. The onset of puberty was identified by monitoring fecal steroids. Juveniles showed higher totals of daily activity and differences in the daily distribution of activity in relation to parents, in which the bimodal profile was characterized by higher levels in evening activity in relation to morning activity. Regarding the phase, the activity onset and offset, occurred later in relation to parents. After entering puberty, the activity onset and offset occurred later and there was an increase in total daily activity. On the other hand, when assessing the effect of sex, only females showed a delay in the activity offset and an increase in total daily activity. Therefore, the circadian activity rhythm in marmosets has peculiar characteristics in the juvenile stage in relation to the total of daily activity, the onset and offset of the active phase, and the distribution of activity during this phase. Besides, the entering puberty was associated with a phase delay and increase on total daily activity, with differences between sexes, possibly due to hormonal influences and/or social modulation on rhythm. PMID:26724713

  9. The Effect of Habitat Acoustics on Common Marmoset Vocal Signal Transmission

    PubMed Central

    MORRILL, RYAN J.; THOMAS, A. WREN; SCHIEL, NICOLA; SOUTO, ANTONIO; MILLER, CORY T.

    2013-01-01

    Noisy acoustic environments present several challenges for the evolution of acoustic communication systems. Among the most significant is the need to limit degradation of spectro-temporal signal structure in order to maintain communicative efficacy. This can be achieved by selecting for several potentially complementary processes. Selection can act on behavioral mechanisms permitting signalers to control the timing and occurrence of signal production to avoid acoustic interference. Likewise, the signal itself may be the target of selection, biasing the evolution of its structure to comprise acoustic features that avoid interference from ambient noise or degrade minimally in the habitat. Here, we address the latter topic for common marmoset (Callithrix jacchus) long-distance contact vocalizations, known as phee calls. Our aim was to test whether this vocalization is specifically adapted for transmission in a species-typical forest habitat, the Atlantic forests of northeastern Brazil. We combined seasonal analyses of ambient habitat acoustics with experiments in which pure tones, clicks, and vocalizations were broadcast and rerecorded at different distances to characterize signal degradation in the habitat. Ambient sound was analyzed from intervals throughout the day and over rainy and dry seasons, showing temporal regularities across varied timescales. Broadcast experiment results indicated that the tone and click stimuli showed the typically inverse relationship between frequency and signaling efficacy. Although marmoset phee calls degraded over distance with marked predictability compared with artificial sounds, they did not otherwise appear to be specially designed for increased transmission efficacy or minimal interference in this habitat. We discuss these data in the context of other similar studies and evidence of potential behavioral mechanisms for avoiding acoustic interference in order to maintain effective vocal communication in common marmosets. PMID

  10. Variations in Male Parenting Behavior and Physiology in the Common Marmoset

    PubMed Central

    ZIEGLER, TONI E.; PRUDOM, SHELLEY L.; ZAHED, SOFIA R.

    2016-01-01

    Infant survival and wellbeing is dependent upon good parenting skills. In some species of primates, fathers are necessary to ensure both positive developmental and social outcomes for their offspring. Common marmosets and the related cotton-top tamarin monkeys provide extensive paternal care of multiple offspring and are essential for infant survival. However, we have found significant variation in a father’s motivation to respond to infant stimuli. Additionally, marmoset males who are experienced fathers are significantly more motivated to respond to infants and infant stimuli than adult males who have yet to be fathers. Expectant fathers appear to be preparing for their energetic role in infant care by responding with increases in multiple reproductive hormones and showing weight gain during their mate’s pregnancy. Male marmosets have been shown to be hormonally responsive to scent signals. Males show increased testosterone shortly after smelling periovulatory scents and lower levels of testosterone following presentation of their own infant’s scent. These two inverse testosterone responses combined indicate that paternal males have a flexible system of responding to socially relevant odor cues. Thus males can be ready to mate when their mate is fertile while continuing to be responsive to their infants when these two events occur simultaneously. A male’s hormonal and physical responsiveness to parenting may be due to pair bonding between the male and his mate. Examining the variability between males in their behavioral, physical, and hormonal responses to their mate’s pregnancy, and infant stimuli provides the means for determining the mechanisms of good parenting in fathers. PMID:19367571

  11. Influence of the mother's reproductive state on the hormonal status of daughters in marmosets (Callithrix kuhlii).

    PubMed

    Puffer, Alyssa M; Fite, Jeffrey E; French, Jeffrey A; Rukstalis, Michael; Hopkins, Elizabeth C; Patera, Kimberly J

    2004-09-01

    Behavioral and endocrine suppression of reproduction in subordinate females produces the high reproductive skew that characterizes callitrichid primate mating systems. Snowdon et al. [American Journal of Primatology 31:11-21, 1993] reported that the eldest daughters in tamarin families exhibit further endocrinological suppression immediately following the birth of siblings, and suggested that dominant females exert greater control over subordinate endocrinology during this energetically challenging phase of reproduction. We monitored the endocrine status of five Wied's black tufted-ear marmoset daughters before and after their mother delivered infants by measuring concentrations of urinary estradiol (E(2)), pregnanediol glucuronide (PdG), testosterone (T), and cortisol (CORT). Samples were collected from marmoset daughters 4 weeks prior to and 9 weeks following three consecutive sibling-litter births when the daughters were prepubertal (M=6.1 months of age), peripubertal (M=11.9 months), and postpubertal (M=17.6 months). The birth of infants was associated with reduced ovarian steroid excretion only in the prepubertal daughters. In contrast, ovarian steroid levels tended to increase in the postpubertal daughters. Urinary E(2) and T levels in the postpubertal daughters were 73.8% and 37.6% higher, respectively, in the 3 weeks following the birth of infants, relative to prepartum levels. In addition, peak urinary PdG concentrations in peri- and postpubertal daughters were equivalent to luteal phase concentrations in nonpregnant, breeding adult females, and all of the peri- and postpubertal daughters showed clear ovulatory cycles. Cortisol excretion did not change in response to the reproductive status of the mother, nor did the concentrations change across age. Our data suggest that marmoset daughters of potential breeding age are not hormonally suppressed during the mother's peripartum period or her return to fertility. These findings provide an additional example

  12. Expression of Synaptic and Phototransduction Markers During Photoreceptor Development in the Marmoset Monkey Callithrix jacchus

    PubMed Central

    HENDRICKSON, ANITA; TROILO, DAVID; DJAJADI, HIDAYAT; POSSIN, DANIEL; SPRINGER, ALAN

    2009-01-01

    Marmoset photoreceptor development was studied to determine the expression sequence for synaptic, opsin, and phototransduction proteins. All markers appear first in cones within the incipient foveal center or in rods at the foveal edge. Recoverin appears in cones across 70% of the retina at fetal day (Fd) 88, indicating that it is expressed shortly after photoreceptors are generated. Synaptic markers synaptophysin, SV2, glutamate vesicular transporter 1, and CTBP2 label foveal cones at Fd 88 and cones at the retinal edge around birth. Cones and rods have distinctly different patterns of synaptic protein and opsin expression. Synaptic markers are expressed first in cones, with a considerable delay before they appear in rods at the same eccentricity. Cones express synaptic markers 2–3 weeks before they express opsin, but rods express opsin 2–4 weeks before rod synaptic marker labeling is detected. Medium/long-wavelength-selective (M&L) opsin appears in foveal cones and rod opsin in rods around the fovea at Fd 100. Very few cones expressing short-wavelength-selective (S) opsin are found in the Fd 105 fovea. Across peripheral retina, opsin appears first in rods, followed about 1 week later by M&L cone opsin. S cone opsin appears last, and all opsins reach the retinal edge by 1 week after birth. Cone transducin and rod arrestin are expressed concurrently with opsin, but cone arrestin appears slightly later. Marmoset photoreceptor development differs from that in Macaca and humans. It starts relatively late, at 56% gestation, compared with Macaca at 32% gestation. The marmoset opsin expression sequence is also different from that of either Macaca or human. PMID:19003975

  13. Oxytocin is associated with infant-care behavior and motivation in cooperatively breeding marmoset monkeys.

    PubMed

    Finkenwirth, Christa; Martins, Eloisa; Deschner, Tobias; Burkart, Judith M

    2016-04-01

    The neurohormone oxytocin (OT) is positively involved in the regulation of parenting and social bonding in mammals, and may thus also be important for the mediation of alloparental care. In cooperatively breeding marmosets, infants are raised in teamwork by parents and adult and sub-adult non-reproductive helpers (usually older siblings). Despite high intrinsic motivation, which may be mediated by hormonal priming, not all individuals are always equally able to contribute to infant-care due to competition among care-takers. Among the various care-taking behaviors, proactive food sharing may reflect motivational levels best, since it can be performed ad libitum by several individuals even if competition among surplus care-takers constrains access to infants. Our aim was to study the link between urinary OT levels and care-taking behaviors in group-living marmosets, while taking affiliation with other adults and infant age into account. Over eight reproductive cycles, 26 individuals were monitored for urinary baseline OT, care-taking behaviors (baby-licking, -grooming, -carrying, and proactive food sharing), and adult-directed affiliation. Mean OT levels were generally highest in female breeders and OT increased significantly in all individuals after birth. During early infancy, high urinary OT levels were associated with increased infant-licking but low levels of adult-affiliation, and during late infancy, with increased proactive food sharing. Our results show that, in marmoset parents and alloparents, OT is positively involved in the regulation of care-taking, thereby reflecting the changing needs during infant development. This particularly included behaviors that are more likely to reflect intrinsic care motivation, suggesting a positive link between OT and motivational regulation of infant-care. PMID:26836769

  14. Changes in endocrine profile and reproductive organs during puberty in the male marmoset monkey (Callithrix jacchus).

    PubMed

    Chandolia, Ramesh K; Luetjens, Craig Marc; Wistuba, Joachim; Yeung, Ching-Hei; Nieschlag, Eberhard; Simoni, Manuela

    2006-08-01

    Data on pubertal maturation in male marmoset, a model for human reproduction, are scant and conflicting. We collected data on novel parameters to characterize puberty. Twenty-five marmoset monkeys were assigned to five age groups by weeks (wk): 21 (pre-pubertal), 43 (onset of puberty), 52 (fully pubertal), 70 (mature), and 116 (fully adult). Serum and intratesticular testosterone and pituitary bioactive chorionic gonadotropin (bioCG) were measured. Testicular development was assessed by ultrasonography, histology, and flow cytometry. Three consecutive blood samples revealed extreme fluctuations in testosterone concentrations, suggesting an erratic secretion. Age-related changes in serum testosterone and pituitary bioCG concentrations were observed. Intratesticular androgens (ITAs) showed high fluctuations within groups at all ages and were high in some animals by 21 wk. Unexpectedly, no correlation between pituitary bioCG and serum testosterone or ITAs was found, but these parameters significantly correlated with testicular weight and volume. These observations were consistent a dependence on the testis growth on bioCG. Unfortunately, the low serum levels of bioCG were not measurable in this study. At 43 wk, the animals reached puberty. At 52 wk of age, animals attained maximum body and epididymal weights and qualitatively normal spermatogenesis, but testes continued growing, reaching a maximum of all parameters at 70 wk of age, without further major changes at the age of 116 wk. It is concluded that (1) gonadal activation is evident at wk 21, (2) the male marmoset reaches the pubertal threshold around 43 wk of age, attains qualitative parameters at 52 wk, matures further to sexual maturity at 70 wk, and (3) serum testosterone and ITAs are highly variable without any identifiable correlation with pituitary bioCG.

  15. Circadian activity rhythm in pre-pubertal and pubertal marmosets (Callithrix jacchus) living in family groups.

    PubMed

    Melo, Paula R; Gonçalves, Bruno S B; Menezes, Alexandre A L; Azevedo, Carolina V M

    2016-03-01

    In marmosets, a phase advance was observed in activity onset in pubertal animals living in captivity under semi-natural conditions which had stronger correlation with the times of sunrise over the course of the year than the age of the animal. In order to evaluate the effect of puberty on the circadian activity rhythm in male and female marmosets living in family groups in controlled lighting conditions, the activity of 5 dyads of twins (4 ♀/♂ and 1 ♂/♂) and their respective parents was continuously monitored by actiwatches between the 4th and 12th months of age. The families were kept under LD 12:12 h with constant humidity and temperature. The onset of puberty was identified by monitoring fecal steroids. Juveniles showed higher totals of daily activity and differences in the daily distribution of activity in relation to parents, in which the bimodal profile was characterized by higher levels in evening activity in relation to morning activity. Regarding the phase, the activity onset and offset, occurred later in relation to parents. After entering puberty, the activity onset and offset occurred later and there was an increase in total daily activity. On the other hand, when assessing the effect of sex, only females showed a delay in the activity offset and an increase in total daily activity. Therefore, the circadian activity rhythm in marmosets has peculiar characteristics in the juvenile stage in relation to the total of daily activity, the onset and offset of the active phase, and the distribution of activity during this phase. Besides, the entering puberty was associated with a phase delay and increase on total daily activity, with differences between sexes, possibly due to hormonal influences and/or social modulation on rhythm.

  16. Patterns on serpentine shapes elicit visual attention in marmosets (Callithrix jacchus).

    PubMed

    Wombolt, Jessica R; Caine, Nancy G

    2016-09-01

    Given the prevalence of threatening snakes in the evolutionary history, and modern-day environments of human and nonhuman primates, sensory, and perceptual abilities that allow for quick detection of, and appropriate response to snakes are likely to have evolved. Many studies have demonstrated that primates recognize snakes faster than other stimuli, and it is suggested that the unique serpentine shape is responsible for its quick detection. However, there are many nonthreatening serpentine shapes in the environment (e.g., vines) that are not threatening; therefore, other cues must be used to distinguish threatening from benign serpentine objects. In two experiments, we systematically evaluated how common marmosets (Callithrix jacchus) visually attend to specific snake-like features. In the first experiment, we examined if skin pattern is a cue that elicits increased visual inspection of serpentine shapes by measuring the amount of time the marmosets looked into a blind before, during, and after presentation of clay models with and without patterns. The marmosets spent the most time looking at the objects, both serpentine and triangle, that were etched with scales, suggesting that something may be uniquely salient about scales in evoking attention. In contrast, they showed relatively little interest in the unpatterned serpentine and control (a triangle) stimuli. In experiment 2, we replicated and extended the results of experiment 1 by adding additional stimulus conditions. We found that patterns on a serpentine shape generated more inspection than those same patterns on a triangle shape. We were unable to confirm that a scaled pattern is unique in its ability to elicit visual interest; the scaled models elicited similar looking times as line and star patterns. Our data provide a foundation for future research to examine how snakes are detected and identified by primates. Am. J. Primatol. 78:928-936, 2016. © 2016 Wiley Periodicals, Inc.

  17. Origin and terminal distribution of the trigeminal projections to the inferior and superior colliculi in the lesser hedgehog tenrec.

    PubMed

    Künzle, H

    1998-01-01

    The trigemino-tectal projections were investigated with anterograde and retrograde tracing techniques in the Madagascan lesser hedgehog tenrec, Echinops telfairi. There were prominent contralateral projections to the inferior colliculus (CoI) and the superior colliculus (CoS), each showing its own characteristic pattern of terminations. While the projections to the CoI were confined consistently to a circumscribed region in its ventrolateral, external portion, the projections from particularly the rostral trigeminal subdivision to the CoS were distributed inhomogenously across almost the entire rostro-caudal and mediolateral extents. Comparing these data with the spino-tectal projections published previously, it demonstrates that the somatotopic organization of ascending tectal afferents is more distinct in the CoI than in the CoS. There were roughly twice as many trigeminal neurones projecting to the CoS than to the CoI. This difference might be due to the fact that the cells projecting to CoS were distributed extensively across the trigeminal nuclear complex (peak densities in the principal and interpolar subdivisions), while the neurones projecting to the CoI were largely confined to the interpolar and caudal trigeminal subdivisions. The latter cells were located adjacent to the spinal trigeminal tract; the neurones projecting to the CoS occupied preferentially the ventral trigeminal regions at rostral levels, while from the interpolar subdivision caudalward the labelled cells shifted dorsolaterally. In comparison to other mammals the trigeminal projection to the tenrec's CoI is unique. There is evidence for such a projection in other species too, but it is poorly documented, presumably due to technical reasons.

  18. Visual responses of neurones in cat superior colliculus in relation to fixation of targets.

    PubMed Central

    Peck, C K

    1989-01-01

    1. Visually elicited discharges were recorded from single cells in the intermediate and deep layers of the superior colliculus of alert, trained cats. With the behavioural protocols used, vigorous and consistent visual responses to the onset and offset of small, stationary targets were encountered in all layers of the colliculus. In addition, the responses of many cells depended on the behavioural context in which the response occurred. Specifically, thirty-nine cells were encountered in which discharge was contingent upon prolonged fixation of the visual stimulus. Thirty of these were located in the intermediate and deep layers and comprised 22% of the 134 isolated cells which were not related to saccadic eye movement. 2. Fixation-related cells showed sustained increases or decreases in firing during fixation of a visual target. Responses to presentation of a visual target at the same retinal location, without active fixation by the animal, were either absent, much weaker, or had extremely variable latencies. 3. Changes in activity were well established by the end of the fixation saccade. The neuronal response was sustained if fixation was sustained. Moreover, the neuronal response began to decrease before the onset of the saccade which broke fixation even though the receptive field location of the target had not yet changed. 4. In these neurones, the discharge rate was not a function of the position of the eye in the orbit. 5. Neurones in which the discharge rate was suppressed during fixation had larger receptive fields than cells in which the discharge rate was enhanced during fixation. There were fewer fixation-suppressed cells (n = 7, 5%) than fixation-activated cells (n = 23, 17%). PMID:2607434

  19. Comparison of marmoset and human FSH using synthetic peptides of the β-subunit L2 loop region and anti-peptide antibodies.

    PubMed

    Kutteyil, Susha S; Kulkarni, Bhalchandra J; Mojidra, Rahul; Joseph, Shaini; Pathak, Bhakti R; Mahale, Smita D

    2016-06-01

    Follicle stimulating hormone (FSH) is a glycoprotein hormone required for female and male gametogenesis in vertebrates. Common marmoset (Callithrix jacchus) is a New World primate monkey, used as animal model in biomedical research. Observations like, requirement of extremely high dose of human FSH in marmosets for superovulation compared to other primates and generation of antibodies in marmoset against human FSH after repeated superovulation cycles, point towards the possibility that FSH-FSH receptor (FSHR) interaction in marmosets might be different than in the humans. In this study we attempted to understand some of these structural differences using FSH peptides and anti-peptide antibody approach. Based on sequence alignment, in silico modeling and docking studies, L2 loop of FSH β-subunit (L2β) was found to be different between marmoset and human. Hence, peptides corresponding to region 32-50 of marmoset and human L2β loop were synthesized, purified and characterized. The peptides displayed dissimilarity in terms of molecular mass, predicted isoelectric point, predicted charge and in the ability to inhibit hormone-receptor interaction. Polyclonal antibodies generated against both the peptides were found to exhibit specific binding for the corresponding peptide and parent FSH in ELISA and Western blotting respectively and exhibited negligible reactivity to cross-species peptide and FSH in ELISA. The anti-peptide antibody against marmoset FSH was also able to detect native FSH in marmoset plasma samples and pituitary sections. In summary, the L2β loop of marmoset and human FSH has distinct receptor interaction ability and immunoreactivity indicating possibility of subtle conformational and biochemical differences between the two regions which may affect the FSH-FSHR interaction in these two primates. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. PMID:27282136

  20. Congenital malformation of the vaginal orifice, imperforate vagina, in the common marmoset (Callithrix jacchus).

    PubMed

    Niimi, Kimie; Oguchi, Ayaka; Nishio, Kenji; Okano, Yasushi; Takahashi, Eiki

    2015-03-01

    The following is a report on a congenital vaginal malformation, imperforate vagina, in the common marmoset (Callithrix jacchus). This anomaly was observed for the first time in an adult female in our research colony. There was no uterine and vaginal aplasia or atresia in her grossly normal genital tract. The plasma progesterone concentration suggested that the ovarian cycle had ceased. However, this may not be related to a functional anomaly, but rather to suppressed ovulation resulting from subordination to cagemates considering the various stages of follicular development observed.

  1. Neuronal MHC Class I Molecules are Involved in Excitatory Synaptic Transmission at the Hippocampal Mossy Fiber Synapses of Marmoset Monkeys

    PubMed Central

    Zhang, Mingyue; Schlumbohm, Christina; Mätz-Rensing, Kerstin; Uchanska-Ziegler, Barbara; Flügge, Gabriele; Zhang, Weiqi; Walter, Lutz; Fuchs, Eberhard

    2010-01-01

    Several recent studies suggested a role for neuronal major histocompatibility complex class I (MHCI) molecules in certain forms of synaptic plasticity in the hippocampus of rodents. Here, we report for the first time on the expression pattern and functional properties of MHCI molecules in the hippocampus of a nonhuman primate, the common marmoset monkey (Callithrix jacchus). We detected a presynaptic, mossy fiber-specific localization of MHCI proteins within the marmoset hippocampus. MHCI molecules were present in the large, VGlut1-positive, mossy fiber terminals, which provide input to CA3 pyramidal neurons. Furthermore, whole-cell recordings of CA3 pyramidal neurons in acute hippocampal slices of the common marmoset demonstrated that application of antibodies which specifically block MHCI proteins caused a significant decrease in the frequency, and a transient increase in the amplitude, of spontaneous excitatory postsynaptic currents (sEPSCs) in CA3 pyramidal neurons. These findings add to previous studies on neuronal MHCI molecules by describing their expression and localization in the primate hippocampus and by implicating them in plasticity-related processes at the mossy fiber–CA3 synapses. In addition, our results suggest significant interspecies differences in the localization of neuronal MHCI molecules in the hippocampus of mice and marmosets, as well as in their potential function in these species. Electronic supplementary material The online version of this article (doi:10.1007/s10571-010-9510-3) contains supplementary material, which is available to authorized users. PMID:20232136

  2. The dopamine D3/D2 receptor agonist 7-OH-DPAT induces cognitive impairment in the marmoset.

    PubMed

    Smith, A G; Neill, J C; Costall, B

    1999-06-01

    Previous work has shown that dopaminergic systems are involved in cognitive function in the common marmoset. The present study investigated the role of dopamine D3 receptors in cognitive performance in the marmoset. The effects of the putative dopamine D3 receptor agonist, 7-OH-DPAT, on performance of a same-day reversal visual object discrimination task were assessed using a miniature Wisconsin General Test Apparatus (WGTA). Within the same test session marmosets acquired a two-choice object discrimination initial task and a reversal task to criterion. 7-OH-DPAT (6-10 microg/kg) significantly impaired reversal task performance only, without affecting acquisition of the initial task. A higher dose of 25 microg/kg 7-OH-DPAT impaired initial task acquisition as well as reversal task acquisition, possibly as a consequence of a nonspecific influence on motor function. The dopamine D2 receptor antagonist (-)sulpiride (5-10 microg/kg) and the alpha2-receptor antagonist yohimbine (50 microg/kg) failed to attenuate the effects of 7-OH-DPAT (6 microg/kg) in this task. In contrast, the dopamine D2/D3 receptor antagonist raclopride (50 microg/kg) significantly attenuated the 7-OH-DPAT-induced impairment of reversal task performance. These results suggest that activation of dopamine D3 receptors produces a selective impairment of aspects of cognitive function in the marmoset.

  3. An Observational Investigation of Behavioral Contagion in Common Marmosets (Callithrix jacchus): Indications for Contagious Scent-Marking.

    PubMed

    Massen, Jorg J M; Šlipogor, Vedrana; Gallup, Andrew C

    2016-01-01

    Behavioral contagion is suggested to promote group coordination that may facilitate activity transitions, increased vigilance, and state matching. Apart from contagious yawning, however, very little attention has been given to this phenomenon, and studies on contagious yawning in primates have so far only focused on Old World monkeys and apes. Here we studied behavioral contagion in common marmosets, a species for which group coordination and vigilance are paramount. In particular, we investigated the contagiousness of yawning, stretching, scratching, tongue protrusion, gnawing, and scent-marking. We coded these behaviors from 14 adult marmosets, from two different social groups. During testing sessions, animals were separated into groups of four individuals for 20-min observation periods, across three distinct diurnal time points (morning, midday, and afternoon) to test for circadian patterns. We observed almost no yawning (0.12 yawns/h) and very little stretching behavior. For all other behaviors, which were more common, we found several temporal and inter-individual differences (i.e., sex, age, dominance status) predictive of these responses. Moreover, we found that gnawing and scent-marking, which almost always co-occurred as a fixed-action pattern, were highly temporally clustered within observation sessions. We discuss the relative absence of yawning in marmosets as well as the possible function of contagious scent-marking, and provide suggestions for future research into the proximate and ultimate functions of these behaviors in marmosets. PMID:27563294

  4. An Observational Investigation of Behavioral Contagion in Common Marmosets (Callithrix jacchus): Indications for Contagious Scent-Marking

    PubMed Central

    Massen, Jorg J. M.; Šlipogor, Vedrana; Gallup, Andrew C.

    2016-01-01

    Behavioral contagion is suggested to promote group coordination that may facilitate activity transitions, increased vigilance, and state matching. Apart from contagious yawning, however, very little attention has been given to this phenomenon, and studies on contagious yawning in primates have so far only focused on Old World monkeys and apes. Here we studied behavioral contagion in common marmosets, a species for which group coordination and vigilance are paramount. In particular, we investigated the contagiousness of yawning, stretching, scratching, tongue protrusion, gnawing, and scent-marking. We coded these behaviors from 14 adult marmosets, from two different social groups. During testing sessions, animals were separated into groups of four individuals for 20-min observation periods, across three distinct diurnal time points (morning, midday, and afternoon) to test for circadian patterns. We observed almost no yawning (0.12 yawns/h) and very little stretching behavior. For all other behaviors, which were more common, we found several temporal and inter-individual differences (i.e., sex, age, dominance status) predictive of these responses. Moreover, we found that gnawing and scent-marking, which almost always co-occurred as a fixed-action pattern, were highly temporally clustered within observation sessions. We discuss the relative absence of yawning in marmosets as well as the possible function of contagious scent-marking, and provide suggestions for future research into the proximate and ultimate functions of these behaviors in marmosets. PMID:27563294

  5. Functional organization of the left inferior precentral sulcus: dissociating the inferior frontal eye field and the inferior frontal junction.

    PubMed

    Derrfuss, J; Vogt, V L; Fiebach, C J; von Cramon, D Y; Tittgemeyer, M

    2012-02-15

    Two eye fields have been described in the human lateral frontal cortex: the frontal eye field (FEF) and the inferior frontal eye field (iFEF). The FEF has been extensively studied and has been found to lie at the ventral part of the superior precentral sulcus. Much less research, however, has focused on the iFEF. Recently, it was suggested that the iFEF is located at the dorsal part of the inferior precentral sulcus. A similar location was proposed for the inferior frontal junction area (IFJ), an area thought to be involved in cognitive control processes. The present study used fMRI to clarify the topographical and functional relationship of the iFEF and the IFJ in the left hemispheres of individual participants. The results show that both the iFEF and the IFJ are indeed located at the dorsal part of the inferior precentral sulcus. Nevertheless, the activations were spatially dissociable in every individual examined. The IFJ was located more towards the depth of the inferior precentral sulcus, close to the junction with the inferior frontal sulcus, whereas the iFEF assumed a more lateral, posterior and superior position. Furthermore, the results provided evidence for a functional double dissociation: the iFEF was activated only in a comparison of saccades vs. button presses, but not in a comparison of incongruent vs. congruent Stroop conditions, while the opposite pattern was found at the IFJ. These results provide evidence for a spatial and functional dissociation of two directly adjacent areas in the left posterior frontal lobe.

  6. Metabolome-wide association study of phenylalanine in plasma of common marmosets

    PubMed Central

    Go, Young-Mi; Walker, Douglas I.; Soltow, Quinlyn A.; Uppal, Karan; Wachtman, Lynn M.; Strobel, Fredrick H.; Pennell, Kurt; Promislow, Daniel E. L.; Jones, Dean P.

    2014-01-01

    Little systematic knowledge exists concerning the impacts of cumulative lifelong exposure, termed the exposome, on requirements for nutrients. Phenylalanine (Phe) is an essential dietary amino acid with an aromatic ring structure similar to endogenous metabolites, dietary compounds and environmental agents. Excess plasma Phe in genetic disease or nutritional deficiency of Phe has adverse health consequences. In principle, structurally similar chemicals interfering with Phe utilization could alter Phe requirement at an individual level. As a strategy to identify components of the exposome that could interfere with Phe utilization, we tested for metabolites correlating with Phe concentration in plasma of a non-human primate species, common marmosets (Callithrix jacchus). The results of tests for more than 5000 chemical features detected by high-resolution metabolomics showed 17 positive correlations with Phe metabolites and other amino acids. Positive and negative correlations were also observed for 33 other chemicals, which included matches to endogenous metabolites and dietary, microbial and environmental chemicals in database searches. Chemical similarity analysis showed many of the matches had high structural similarity to Phe. Together, the results show that chemicals in marmoset plasma could impact Phe utilization. Such chemicals could contribute to early lifecycle developmental disorders when neurological development is vulnerable to Phe levels. PMID:25526869

  7. Memory, transmission and persistence of alternative foraging techniques in wild common marmosets

    PubMed Central

    Gunhold, Tina; Massen, Jorg J.M.; Schiel, Nicola; Souto, Antonio; Bugnyar, Thomas

    2014-01-01

    Experimental studies on traditions in animals have focused almost entirely on the initial transmission phase in captive populations. We conducted an open diffusion field experiment with 13 groups of wild common marmosets, Callithrix jacchus. Seven groups contained individuals that were already familiar with the task (‘push or pull’ box) and thus served as potential models for naïve individuals. Additionally, in four groups one individual was trained for one of the two possible techniques and in two control groups no skilled individuals were present. First, we investigated whether experienced individuals would remember how to solve the task even after 2 years without exposure and whether they would still prefer their learned technique. Second, we tested whether naïve individuals would learn socially from their skilled family members and, more importantly, whether they would use the same technique. Third, we conducted several test blocks to see whether the individual and/or group behaviour would persist over time. Our results show that wild common marmosets were able to memorize, learn socially and maintain preferences of foraging techniques. This field experiment thus reveals a promising approach to studying social learning in the wild and provides the basis for long-term studies on tradition formation. PMID:24910466

  8. The transcriptomes of novel marmoset monkey embryonic stem cell lines reflect distinct genomic features

    PubMed Central

    Debowski, Katharina; Drummer, Charis; Lentes, Jana; Cors, Maren; Dressel, Ralf; Lingner, Thomas; Salinas-Riester, Gabriela; Fuchs, Sigrid; Sasaki, Erika; Behr, Rüdiger

    2016-01-01

    Embryonic stem cells (ESCs) are useful for the study of embryonic development. However, since research on naturally conceived human embryos is limited, non-human primate (NHP) embryos and NHP ESCs represent an excellent alternative to the corresponding human entities. Though, ESC lines derived from naturally conceived NHP embryos are still very rare. Here, we report the generation and characterization of four novel ESC lines derived from natural preimplantation embryos of the common marmoset monkey (Callithrix jacchus). For the first time we document derivation of NHP ESCs derived from morula stages. We show that quantitative chromosome-wise transcriptome analyses precisely reflect trisomies present in both morula-derived ESC lines. We also demonstrate that the female ESC lines exhibit different states of X-inactivation which is impressively reflected by the abundance of the lncRNA X inactive-specific transcript (XIST). The novel marmoset ESC lines will promote basic primate embryo and ESC studies as well as preclinical testing of ESC-based regenerative approaches in NHP. PMID:27385131

  9. Analysis of the lateral geniculate nucleus in dichromatic and trichromatic marmosets.

    PubMed

    FitzGibbon, Thomas; Eriköz, Bahar; Grünert, Ulrike; Martin, Paul R

    2015-09-01

    Marmosets are diurnal New World monkeys that show sex-linked cone photopigment polymorphism, whereby all males and some females are dichromats ("red-green colorblind"), but most females show trichromatic color vision. Here we asked whether trichromats express chromatic-specific circuitry in the lateral geniculate nucleus (LGN). The volume of parvocellular (P), magnocellular (M), and koniocellular (K) layers was calculated in Nissl-stained sections from the LGN of adult marmosets (Callithrix jacchus; 10 trichromatic females; 2 dichromatic females; and 13 dichromatic males). Retinal ganglion cell axon terminals within the P and K layers were reconstructed and measured following anterograde tracer (dextran) injections. We show that there is little difference in LGN layer volume with respect to age, weight, or sex of the animals, or between dichromatic and trichromatic phenotypes. The morphology of retinal ganglion cell terminals was largely indistinguishable on comparing dichromats and trichromats, and likewise on comparing terminals representing peripheral or foveal retina. We conclude that the LGN circuits we studied are largely independent of red-green color vision phenotype and visual field location. PMID:25753496

  10. Degree of social contact affects the emission of food calls in the common marmoset (Callithrix jacchus).

    PubMed

    Vitale, Augusto; Zanzoni, Michela; Queyras, Armelle; Chiarotti, Flavia

    2003-01-01

    The aim of this study was to investigate whether the emission of food calls in common marmosets (Callithrix jacchus) is influenced by different social contexts. Food calls are emitted by this species only in the presence of preferred food. If these calls have any communicative function, it may be that individuals produce food calls in order to call family mates toward the food source. If this is the case, the number of calls produced should vary in accordance with the number of family mates present at the moment of the discovery of the food, i.e., the fewer family mates nearby, the more food calls are emitted. This hypothesis was tested with five pairs of common marmosets, by recording the number of food calls emitted in four experimental conditions: 1). isolation: completely isolated from the family mates; 2). visual isolation: separated by a wooden panel from the family mates; 3). visual contact: separated by a wire-mesh from the family mates; and 4). physical interaction: together with the family mates. The results show that the proportion of intervals during which food calls were produced by the pairs was significantly different in the four experimental conditions. It decreased from the isolation and visual isolation condition, through the visual contact condition, reaching the lowest value in the physical interaction condition. The variation observed in the proportion of intervals during which food calls were emitted, in relation to different social contexts, is an indication in favor of the communicative function of this vocalization.

  11. Isolation of an arenavirus from a marmoset with callitrichid hepatitis and its serologic association with disease.

    PubMed Central

    Stephensen, C B; Jacob, J R; Montali, R J; Holmes, K V; Muchmore, E; Compans, R W; Arms, E D; Buchmeier, M J; Lanford, R E

    1991-01-01

    Callitrichid hepatitis (CH) is an acute, often fatal viral infection of New World primates from the family Callitrichidae. The etiologic agent of CH is unknown. We report here the isolation of an arenavirus from a common marmoset (Callithrix jacchus) with CH by using in vitro cultures of marmoset hepatocytes and Vero-E6 cells. Enveloped virions 67 to 133 nm in diameter with ribosomelike internal structures were seen in infected cultures. Immunofluorescence and Western immunoblot analysis using CH-specific antisera (principally from animals exposed to CH during zoo outbreaks) revealed three antigens in cells infected with this CH-associated virus (CHV). These antigens had the same electrophoretic mobilities on sodium dodecyl sulfate-polyacrylamide gels as did the nucleocapsid, GP2, and GPC proteins of lymphocytic choriomeningitis virus (LCMV). Monoclonal antibodies specific for these arenavirus proteins also reacted with the three CHV antigens. Conversely, the CH-specific antisera reacted with the nucleocapsid, GP2, and GPC proteins of LCMV. CHV thus appears to be a close antigenic relative of LCMV. The serologic association of CHV with several CH outbreaks implicate it as the etiologic agent of this disease. Images PMID:1712856

  12. Can we measure brain efficiency? An empirical test with common marmosets (Callithrix jacchus).

    PubMed

    Strasser, Andrea; Burkart, Judith M

    2012-01-01

    Various measures of brain size correlate with cognitive performance; however, the fit is not perfect, which bears the question of whether brains also vary in efficiency. Such variation could be expected if a species faces constraints on brain enlargement, for example due to the impossibility of slowing down life history as a consequence of predator pressure, while simultaneously experiencing selective benefits from enhanced cognitive ability related to particular ecological or social conditions. Arguably, this applies to callitrichid monkeys and would lead to the prediction that their relatively small brains are particularly efficient in comparison to their sister taxa, Cebus. This study investigated whether callitrichids' cognitive performance is better than would be expected given their brain size rather than comparing absolute performance between the taxa. As a measure of cognitive performance, we used the reversal learning paradigm, which is reliably and closely associated with brain size across primate taxa, and assessed performance in this paradigm (transfer index) in 14 common marmosets (Callithrix jacchus) as representatives of the callitrichids. These marmosets were found to show higher performance than would be expected for their brain size, and this relative performance was also higher than the relative performance in capuchin monkeys. We outline how these effects may be due to the cooperative breeding system of the callitrichids, particularly the enhancement of behavioural and cognitive propensities associated with shared care and provisioning.

  13. Facial expressions in common marmosets (Callithrix jacchus) and their use by conspecifics.

    PubMed

    Kemp, Caralyn; Kaplan, Gisela

    2013-09-01

    Facial expressions have been studied mainly in chimpanzees and have been shown to be important social signals. In platyrrhine and strepsirrhine primates, it has been doubted that facial expressions are differentiated enough, or the species socially capable enough, for facial expressions to be part of their communication system. However, in a series of experiments presenting olfactory, auditory and visual stimuli, we found that common marmosets (Callithrix jacchus) displayed an unexpected variety of facial expressions. Especially, olfactory and auditory stimuli elicited obvious facial displays (such as disgust), some of which are reported here for the first time. We asked whether specific facial responses to food and predator-related stimuli might act as social signals to conspecifics. We recorded two contrasting facial expressions (fear and pleasure) as separate sets of video clips and then presented these to cage mates of those marmosets shown in the images, while tempting the subject with food. Results show that the expression of a fearful face on screen significantly reduced time spent near the food bowl compared to the duration when a face showing pleasure was screened. This responsiveness to a cage mate's facial expressions suggests that the evolution of facial signals may have occurred much earlier in primate evolution than had been thought. PMID:23412667

  14. The transcriptomes of novel marmoset monkey embryonic stem cell lines reflect distinct genomic features.

    PubMed

    Debowski, Katharina; Drummer, Charis; Lentes, Jana; Cors, Maren; Dressel, Ralf; Lingner, Thomas; Salinas-Riester, Gabriela; Fuchs, Sigrid; Sasaki, Erika; Behr, Rüdiger

    2016-01-01

    Embryonic stem cells (ESCs) are useful for the study of embryonic development. However, since research on naturally conceived human embryos is limited, non-human primate (NHP) embryos and NHP ESCs represent an excellent alternative to the corresponding human entities. Though, ESC lines derived from naturally conceived NHP embryos are still very rare. Here, we report the generation and characterization of four novel ESC lines derived from natural preimplantation embryos of the common marmoset monkey (Callithrix jacchus). For the first time we document derivation of NHP ESCs derived from morula stages. We show that quantitative chromosome-wise transcriptome analyses precisely reflect trisomies present in both morula-derived ESC lines. We also demonstrate that the female ESC lines exhibit different states of X-inactivation which is impressively reflected by the abundance of the lncRNA X inactive-specific transcript (XIST). The novel marmoset ESC lines will promote basic primate embryo and ESC studies as well as preclinical testing of ESC-based regenerative approaches in NHP. PMID:27385131

  15. Cutting costs in response to predatory threat by Geoffroy's marmosets (Callithrix geoffroyi).

    PubMed

    Caine, N G

    1998-01-01

    Ideally, prey should respond to their predators efficiently, without over- or underreacting to the threat. This may be particularly important for small-bodied species for whom metabolic demands are high and predatory risk is great. In the current study, two family groups of Callithrix geoffroyi living outside in a rural setting at the Center for Reproduction of Endangered Species, San Diego Wild Animal Park, were observed before, during, and after ten presentations of a great horned owl model. The owl was mounted on a post on a nearby hillside, simulating a situation in which a real but nonimminent threat is posed. As controls, a model of a crow and a cloth bag were also presented, each for ten trials. During the 10 min presentations of the owl, rates of play and foraging decreased, and rates of locomotion and vigilant looking increased from baseline rates. Data on occupation of the best viewing area suggest that the marmosets shared the job of monitoring a potential threat. After the owl was removed, behavior quickly returned to baseline rates, with the exception of looking at the place where the owl had been, and play. Neither the bag nor the crow generated significant differences from the baseline condition that preceded it. Marmosets may reduce the costs of antipredator behavior by appropriately assessing the degree of risk and by quickly resuming important activities once a potential threat has passed. PMID:9802510

  16. Administration of MPTP to the common marmoset does not alter cortical cholinergic function

    SciTech Connect

    Garvey, J.; Petersen, M.; Waters, C.M.; Rose, S.P.; Hunt, S.; Briggs, R.; Jenner, P.; Marsden, C.D.

    1986-01-01

    The administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to common marmosets induced persistent motor deficits and decreased concentrations of dopamine, homovanillic acid, and 3,4-dihydroxy-phenylacetic acid (DOPAC) and (TH)dopamine uptake in the caudate-putamen. There was an 80% reduction in tyrosine hydroxylase immunoreactive cells in substantia nigra. At 10 days following the start of MPTP administration, the activity of choline acetyltransferase in the thalamus and frontal cortex was unchanged compared with control animals. Similarly, specific (TH)QNB binding was unaltered. At 4-6 weeks following the start of MPTP treatment, choline acetyltransferase activity and (TH)QNB binding in the frontal cortex and thalamus remained unaffected. There was no evidence for cell loss in the nucleus basalis of Meynert or alteration in the intensity of staining for acetylcholinesterase. MPTP treatment of the common marmoset produces a nigrostriatal lesion. In contrast, MPTP did not alter cortical cholinergic function and was not neurotoxic to the cholinergic cells in the nucleus basalis of Meynert.

  17. Quality of maternal and paternal care predicts later stress reactivity in the cooperatively-breeding marmoset (Callithrix geoffroyi).

    PubMed

    Birnie, Andrew K; Taylor, Jack H; Cavanaugh, Jon; French, Jeffrey A

    2013-12-01

    Variation in the early postnatal social environment can have lasting effects on hypothalamic-pituitary-adrenal (HPA) axis stress responses. Both rats and macaque monkeys subjected to low quality or abusive maternal care during the early postnatal period have more pronounced HPA responses to environmental stressors throughout development and into adulthood compared to animals reared in higher quality early maternal environments. However, little is known about the relative contributions to HPA stress response styles in developing offspring in species in which offspring care is routinely provided by group members other than the mother, such as in cooperatively breeding mammals. Marmoset monkeys exhibit cooperative offspring rearing, with fathers and older siblings providing care in addition to that provided by the mother. We evaluated the effects of early maternal, paternal, and older sibling care on HPA responses to social separation across development in captive white-faced marmoset offspring (Callithrix geoffroyi). We monitored offspring care by mothers, fathers, and older siblings in marmosets for the first 60 days of life. Later in development, each marmoset experienced three standardized social separation/novelty exposure stressors at 6, 12, and 18 months of age. During separation, we collected urine samples and analyzed them via enzyme immunoassay for cortisol levels. Infants that received higher rates of rejections from the entire family group showed higher cortisol responses to social separation. This relationship was found when mothers, fathers, and older siblings, were analyzed separately as well. No differences in cortisol responses were found between offspring that received high and low rates of carrying or high and low rates of licking and grooming by any group member. In the cooperatively breeding marmoset, early social cues from multiple classes of caregivers may influence HPA stress responses throughout the lifespan.

  18. The Effect of Anesthesia on Blood Pressure Measured Noninvasively by Using the Tail-Cuff Method in Marmosets (Callithrix jacchus).

    PubMed

    Ansel, Tobin V; Nour, Ann K; Benavente-Perez, Alexandra

    2016-01-01

    In this study, we evaluated the validity of measuring blood pressure (BP) noninvasively in marmosets by using the tail-cuff method. The number of measurements needed for a valid reading was calculated by plotting the average SD of 5 consecutive readings in 10 naïve marmosets; the SD for both systolic and diastolic BP readings plateaued after 4 readings. To evaluate how anesthesia (alphaxalone, 15 mg/kg IM) affected BP in marmosets, we measured 4 animals every minute for 60 min after injection. The average length of anesthesia was 47.3 ± 13.2 min. The variability in the systolic and diastolic BP was the smallest at 10 to 30 min after injection (systolic SD, 6.29 mm Hg; diastolic SD, 5.27 mm Hg) and almost doubled at 30 to 60 min after injection (systolic SD, 13.5 mm Hg; diastolic SD, 12.3 mm Hg). The within- and between-session repeatability and reproducibility were calculated by measuring 12 marmosets twice at the same time of day (±1 h) 1 wk apart. The coefficients of repeatability and reproducibility were 1.98% and 14.5% for systolic BP and 3.37% and 16.2% for diastolic BP, respectively. Our results indicate that using the volumetric tail-cuff method to measure BP noninvasively in anesthetized marmosets is safe and feasible. The measures are least variable within 10 to 30 min after the injection of anesthetic, and variability increases slightly between sessions. PMID:27657716

  19. Quality of maternal and paternal care predicts later stress reactivity in the cooperatively-breeding marmoset (Callithrix geoffroyi).

    PubMed

    Birnie, Andrew K; Taylor, Jack H; Cavanaugh, Jon; French, Jeffrey A

    2013-12-01

    Variation in the early postnatal social environment can have lasting effects on hypothalamic-pituitary-adrenal (HPA) axis stress responses. Both rats and macaque monkeys subjected to low quality or abusive maternal care during the early postnatal period have more pronounced HPA responses to environmental stressors throughout development and into adulthood compared to animals reared in higher quality early maternal environments. However, little is known about the relative contributions to HPA stress response styles in developing offspring in species in which offspring care is routinely provided by group members other than the mother, such as in cooperatively breeding mammals. Marmoset monkeys exhibit cooperative offspring rearing, with fathers and older siblings providing care in addition to that provided by the mother. We evaluated the effects of early maternal, paternal, and older sibling care on HPA responses to social separation across development in captive white-faced marmoset offspring (Callithrix geoffroyi). We monitored offspring care by mothers, fathers, and older siblings in marmosets for the first 60 days of life. Later in development, each marmoset experienced three standardized social separation/novelty exposure stressors at 6, 12, and 18 months of age. During separation, we collected urine samples and analyzed them via enzyme immunoassay for cortisol levels. Infants that received higher rates of rejections from the entire family group showed higher cortisol responses to social separation. This relationship was found when mothers, fathers, and older siblings, were analyzed separately as well. No differences in cortisol responses were found between offspring that received high and low rates of carrying or high and low rates of licking and grooming by any group member. In the cooperatively breeding marmoset, early social cues from multiple classes of caregivers may influence HPA stress responses throughout the lifespan. PMID:24099861

  20. Quality of Maternal and Paternal Care Predicts Later Stress Reactivity in the Cooperatively-Breeding Marmoset (Callithrix geoffroyi)

    PubMed Central

    Birnie, Andrew K.; Taylor, Jack H.; Cavanaugh, Jon; French, Jeffrey A.

    2013-01-01

    Variation in the early postnatal social environment can have lasting effects on hypothalamic-pituitary-adrenal (HPA) axis stress responses. Both rats and macaque monkeys subjected to low quality or abusive maternal care during the early postnatal period have more pronounced HPA responses to environmental stressors throughout development and into adulthood compared to animals reared in higher quality early maternal environments. However, little is known about the relative contributions to HPA stress response styles in developing offspring in species in which offspring care is routinely provided by group members other than the mother, such as in cooperatively breeding mammals. Marmoset monkeys exhibit cooperative offspring rearing, with fathers and older siblings providing care in addition to that provided by the mother. We evaluated the effects of early maternal, paternal, and older sibling care on HPA responses to social separation across development in captive white-faced marmoset offspring (Callithrix geoffroyi). We monitored offspring care by mothers, fathers, and older siblings in marmosets for the first 60 days of life. Later in development, each marmoset experienced three standardized social separation/novelty exposure stressors at 6, 12, and 18 months of age. During separation, we collected urine samples and analyzed them via enzyme immunoassay for cortisol levels. Infants that received higher rates of rejections from the entire family group showed higher cortisol responses to social separation. This relationship was found when mothers, fathers, and older siblings, were analyzed separately as well. No differences in cortisol responses were found between offspring that received high and low rates of carrying or high and low rates of licking and grooming by any group member. In the cooperatively breeding marmoset, early social cues from multiple classes of caregivers may influence HPA stress responses throughout the lifespan. PMID:24099861

  1. [Inferior alveolar nerve repositioning in implant surgery].

    PubMed

    Ardekian, L; Salnea, J; Abu el-Naaj, I; Gutmacher, T; Peled, M

    2001-04-01

    Severe resorption of the posterior mandible possesses one of the most difficult restorative challenges to the implant surgery today. This resorption may prevent the placement of dental implants without the potentially damage to the inferior alveolar nerve. To create the opportunity of insertion dental implants of adequately length in those cases, the technique of nerve repositioning has been advocated. The purpose of this article is to describe two cases of nerve repositioning combined with placement of dental implants. Both cases showed appropriate postoperative healing without damage to the inferior alveolar nerve. The inferior alveolar nerve repositioning technique seems to be an acceptable alternative to augmentation procedure prior to dental implants placement in cases exhibiting atrophic posterior mandibular ridges. PMID:11494807

  2. Lateralization Technique and Inferior Alveolar Nerve Transposition

    PubMed Central

    Sanches, Marco Antonio; Ramalho, Gabriel Cardoso; Manzi, Marcello Roberto

    2016-01-01

    Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics. PMID:27433360

  3. Development of a compact and general-purpose experimental apparatus with a touch-sensitive screen for use in evaluating cognitive functions in common marmosets.

    PubMed

    Takemoto, Atsushi; Izumi, Akihiro; Miwa, Miki; Nakamura, Katsuki

    2011-07-15

    Common marmosets have been used extensively in biomedical research and the recent advent of techniques to generate transgenic marmosets has accelerated the use of this model. New methods that efficiently assess the degree of cognitive function in common marmosets are needed in order to establish their suitability as non-human primate models of higher brain function disorders. Here, we have developed a new apparatus suitable for testing the cognitive functions of common marmosets. Utilizing a mini laptop PC with a touch-sensitive screen as the main component, the apparatus is small and lightweight and can be easily attached to the home cages. The ease of designing and testing new paradigms with the flexible software is another advantage of this system. We have tested visual discrimination and its reversal tasks using this apparatus and confirmed its efficacy.

  4. Anatomy of Inferior Mesenteric Artery in Fetuses.

    PubMed

    Nuzhat, Ayesha

    2016-01-01

    Aim. To analyze Inferior Mesenteric Artery in fetuses through its site of origin, length, diameter, and variation of its branches. Method. 100 fetuses were collected from various hospitals in Warangal at Kakatiya Medical College in Andhra Pradesh, India, and were divided into two groups, group I (second-trimester fetuses) and group II (third-trimester fetuses), followed by dissection. Result. (1) Site of Origin. In group I fetuses, origin of Inferior Mesenteric Artery was at third lumbar vertebra in 33 out of 34 fetuses (97.2%). In one fetus it was at first lumbar vertebra, 2.8%. In all group II fetuses, origin of Inferior Mesenteric Artery was at third lumbar vertebra. (2) Length. In group I fetuses it ranged between 18 and 30 mm, average being 24 mm except in one fetus where it was 48 mm. In group II fetuses the length ranged from 30 to 34 mm, average being 32 mm. (3) Diameter. In group I fetuses it ranged from 0.5 to 1 mm, and in group II fetuses it ranged from 1 to 2 mm, average being 1.5 mm. (4) Branches. Out of 34 fetuses of group I, 4 fetuses showed variation. In one fetus left colic artery was arising from abdominal aorta, 2.9%. In 3 fetuses, Inferior Mesenteric Artery was giving a branch to left kidney, 8.8%. Out of 66 fetuses in group II, 64 had normal branching. In one fetus left renal artery was arising from Inferior Mesenteric Artery, 1.5%, and in another fetus one accessory renal artery was arising from Inferior Mesenteric Artery and entering the lower pole of left kidney. Conclusion. Formation, course, and branching pattern of an artery depend on development and origin of organs to attain the actual adult position. PMID:27313956

  5. Novel Marmoset Cytochrome P450 2C19 in Livers Efficiently Metabolizes Human P450 2C9 and 2C19 Substrates, S-Warfarin, Tolbutamide, Flurbiprofen, and Omeprazole.

    PubMed

    Uehara, Shotaro; Uno, Yasuhiro; Inoue, Takashi; Kawano, Mirai; Shimizu, Makiko; Toda, Akiko; Utoh, Masahiro; Sasaki, Erika; Yamazaki, Hiroshi

    2015-10-01

    The common marmoset (Callithrix jacchus), a small New World monkey, has the potential for use in human drug development due to its evolutionary closeness to humans. Four novel cDNAs, encoding cytochrome P450 (P450) 2C18, 2C19, 2C58, and 2C76, were cloned from marmoset livers to characterize P450 2C molecular properties, including previously reported P450 2C8. The deduced amino acid sequence showed high sequence identities (>86%) with those of human P450 2Cs, except for marmoset P450 2C76, which has a low sequence identity (∼70%) with any human P450 2Cs. Phylogenetic analysis showed that marmoset P450 2Cs were more closely clustered with those of humans and macaques than other species investigated. Quantitative polymerase chain reaction analysis showed that all of the marmoset P450 2C mRNAs were predominantly expressed in liver as opposed to the other tissues tested. Marmoset P450 2C proteins were detected in liver by immunoblotting using antibodies against human P450 2Cs. Among marmoset P450 2Cs heterologously expressed in Escherichia coli, marmoset P450 2C19 efficiently catalyzed human P450 2C substrates, S-warfarin, diclofenac, tolbutamide, flurbiprofen, and omeprazole. Marmoset P450 2C19 had high Vmax and low Km values for S-warfarin 7-hydroxylation that were comparable to those in human liver microsomes, indicating warfarin stereoselectivity similar to findings in humans. Faster in vivo S-warfarin clearance than R-warfarin after intravenous administration of racemic warfarin (0.2 mg/kg) to marmosets was consistent with the in vitro kinetic parameters. These results indicated that marmoset P450 2C enzymes had functional characteristics similar to those of humans, and that P450 2C-dependent metabolic properties are likewise similar between marmosets and humans.

  6. Visual Experience Is Required for the Development of Eye Movement Maps in the Mouse Superior Colliculus

    PubMed Central

    Wang, Lupeng; Liu, Mingna

    2015-01-01

    Topographic maps are a fundamental feature of the brain's representations of the sensory environment as well as an efficient way to organize motor control networks. Although great progress has been made in our understanding of sensory map development, very little is known about how topographic representations for motor control develop and interface with sensory maps. Here we map the representation for eye movements in the superior colliculus (SC) in awake mice. As stimulation sites were sampled along the anterior–posterior axis, small amplitude, nasally directed (ipsiversive) saccadic eye movements were evoked by microstimulation in anterior SC, followed by a smooth progression to large, temporally directed (contraversive) movements in posterior SC. This progressive change of movement amplitude and direction is consistent with the global polarity of the retinotopic map in the superficial SC, just as in primates and cats. We then investigated the role of visual experience in the development of eye movement map by studying mice reared in complete darkness. Saccades evoked by SC stimulation as well as spontaneous saccadic eye movements were larger in the dark-reared mice, indicating that visual experience is required to fine-tune the gain of saccades and to establish normal eye movement maps in the SC. Our experiments provide a foundation for future studies to investigate the synaptic organization and developmental mechanisms of sensorimotor transformations in mice. SIGNIFICANCE STATEMENT The superior colliculus (SC) is a midbrain structure important for multisensory integration and sensorimotor transformation. Here we have studied eye movement representations in the SC of mice, a species that has become a popular model in vision research because of available genetic tools. Our studies show mice make saccadic eye movements spontaneously and in response to SC stimulation. The mouse SC contains an eye movement map that has the same global polarity as the overlaying

  7. Fatal attack on black-tufted-ear marmosets (Callithrix penicillata) by a Boa constrictor: a simultaneous assault on two juvenile monkeys.

    PubMed

    Teixeira, Danilo Simonini; dos Santos, Edmilson; Leal, Silvana Gomes; de Jesus, Andrea Karla; Vargas, Waldemir Paixão; Dutra, Irapuan; Barros, Marilia

    2016-01-01

    Here we report the first witnessed attack on a marmoset by a constrictor snake. The incident occurred mid-morning in a gallery forest within an altered landscape of the Cerrado region of central Brazil and refers to a fatal attack by a Boa constrictor on two juvenile black-tufted-ear marmosets (Callithrix penicillata) simultaneously. The snake captured both individuals at a height of ~ 4 m while a group of eight marmosets traveled through the subcanopy. The actual strike was not seen. After 2 min, the boa fell to the ground with both marmosets in its coils and proceeded to kill one animal at a time through constriction. Two adult marmosets immediately descended to where the snake held its victims on the ground and attacked it. The snake showed no apparent reaction, and after ~ 1-2 min, the adults rejoined the remaining group members that were mobbing and vocalizing from 5 to 6 m above. The group left the scene ~ 7 min after the onset of the attack and was not seen again. The snake loosened its coils 10 min after its initial strike, left the two carcasses on the ground and stayed behind a nearby tree. Thus, we are not sure if the victims were in fact ingested. This report confirms that marmosets are vulnerable to boid snakes and capable of highly organized and cooperative antipredation behavior. It also suggests that snakes pose a greater threat to callitrichids than previously thought.

  8. Fatal attack on black-tufted-ear marmosets (Callithrix penicillata) by a Boa constrictor: a simultaneous assault on two juvenile monkeys.

    PubMed

    Teixeira, Danilo Simonini; dos Santos, Edmilson; Leal, Silvana Gomes; de Jesus, Andrea Karla; Vargas, Waldemir Paixão; Dutra, Irapuan; Barros, Marilia

    2016-01-01

    Here we report the first witnessed attack on a marmoset by a constrictor snake. The incident occurred mid-morning in a gallery forest within an altered landscape of the Cerrado region of central Brazil and refers to a fatal attack by a Boa constrictor on two juvenile black-tufted-ear marmosets (Callithrix penicillata) simultaneously. The snake captured both individuals at a height of ~ 4 m while a group of eight marmosets traveled through the subcanopy. The actual strike was not seen. After 2 min, the boa fell to the ground with both marmosets in its coils and proceeded to kill one animal at a time through constriction. Two adult marmosets immediately descended to where the snake held its victims on the ground and attacked it. The snake showed no apparent reaction, and after ~ 1-2 min, the adults rejoined the remaining group members that were mobbing and vocalizing from 5 to 6 m above. The group left the scene ~ 7 min after the onset of the attack and was not seen again. The snake loosened its coils 10 min after its initial strike, left the two carcasses on the ground and stayed behind a nearby tree. Thus, we are not sure if the victims were in fact ingested. This report confirms that marmosets are vulnerable to boid snakes and capable of highly organized and cooperative antipredation behavior. It also suggests that snakes pose a greater threat to callitrichids than previously thought. PMID:26467338

  9. The Distinct Role of the Amygdala, Superior Colliculus and Pulvinar in Processing of Central and Peripheral Snakes

    PubMed Central

    Almeida, Inês; Soares, Sandra C.; Castelo-Branco, Miguel

    2015-01-01

    Introduction Visual processing of ecologically relevant stimuli involves a central bias for stimuli demanding detailed processing (e.g., faces), whereas peripheral object processing is based on coarse identification. Fast detection of animal shapes holding a significant phylogenetic value, such as snakes, may benefit from peripheral vision. The amygdala together with the pulvinar and the superior colliculus are implicated in an ongoing debate regarding their role in automatic and deliberate spatial processing of threat signals. Methods Here we tested twenty healthy participants in an fMRI task, and investigated the role of spatial demands (the main effect of central vs. peripheral vision) in the processing of fear-relevant ecological features. We controlled for stimulus dependence using true or false snakes; snake shapes or snake faces and for task constraints (implicit or explicit). The main idea justifying this double task is that amygdala and superior colliculus are involved in both automatic and controlled processes. Moreover the explicit/implicit instruction in the task with respect to emotion is not necessarily equivalent to explicit vs. implicit in the sense of endogenous vs. exogenous attention, or controlled vs. automatic processes. Results We found that stimulus-driven processing led to increased amygdala responses specifically to true snake shapes presented in the centre or in the peripheral left hemifield (right hemisphere). Importantly, the superior colliculus showed significantly biased and explicit central responses to snake-related stimuli. Moreover, the pulvinar, which also contains foveal representations, also showed strong central responses, extending the results of a recent single cell pulvinar study in monkeys. Similar hemispheric specialization was found across structures: increased amygdala responses occurred to true snake shapes presented to the right hemisphere, with this pattern being closely followed by the superior colliculus and the

  10. Outcomes of Unilateral Inferior Oblique Myectomy Surgery in Inferior Oblique Overaction Due to Superior Oblique Palsy

    PubMed Central

    Yumuşak, Erhan; Yolcu, Ümit; Küçükevcilioğlu, Murat; Diner, Oktay; Mutlu, Fatih Mehmet

    2016-01-01

    Objectives: To present the outcomes of unilateral inferior oblique myectomy performed in patients with inferior oblique overaction due to superior oblique palsy. Materials and Methods: Twenty-seven eyes of 27 patients that underwent inferior oblique myectomy surgery for superior oblique palsy between 2002 and 2008 were included. Inferior oblique overaction scores (between 0-4) at preoperative, early postoperative (within 1 week after surgery) and late postoperative (earliest 6 months) visits were reviewed. Results: There were 12 male and 15 female patients. Eighteen were operated on the right eye, and 9 were operated on the left eye. The mean age was 15.62±13.31 years, and the mean follow-up was 17±11.28 months (range, 6-60 months). Patients who had horizontal component and V-pattern deviation were excluded. Preoperative and early postoperative inferior oblique overaction scores were 2.55±0.75 and 0.14±0.36, respectively, and the difference was statistically significant (p<0.01). This improvement was maintained up to the late postoperative period. Conclusion: Due to its promising short-term and long-term results, inferior oblique myectomy can be the first choice of surgery for inferior oblique overaction due to superior oblique palsy. PMID:27800253

  11. Marmosets treated with oxytocin are more socially attractive to their long-term mate

    PubMed Central

    Cavanaugh, Jon; Huffman, Michelle C.; Harnisch, April M.; French, Jeffrey A.

    2015-01-01

    Adult male-female bonds are partly characterized by initiating and maintaining close proximity with a social partner, as well as engaging in high levels of affiliative and sociosexual behavior. Oxytocin (OXT), a neuromodulatory nonapeptide, plays a critical role in the facilitation of social bonding and prosocial behavior toward a social partner (Feldman, 2012). However, less attention has been given to whether augmentation of OXT levels in an individual alters others’ perceptions and behavior toward an OXT-treated social partner. We examined social dynamics in well-established male-female pairs of marmoset monkeys (Callithrix jacchus) in which one member of the pair was administered an intranasal OXT agonist, an OXT antagonist (OXTA), or saline. OXT treatment did not alter the expression of affiliative toward an untreated partner. However, OXT did significantly influence the expression of proximity and grooming behavior with a treated partner, as a function of OXT treatment and sex. Female interest in initiating and maintaining proximity with a pair-mate was altered by OXT treatment. Untreated female marmosets departed from their saline-treated partner more frequently than they approached them, as indicated by a low proximity index score. However, when males received an intranasal OXT agonist they had a significantly increased proximity index score relative to saline, indicating that their untreated partner approached them more often than they departed from them). Saline-treated females initiated and received equivalent levels of grooming behavior. However, when female marmosets were treated with an OXT agonist their untreated partner groomed them proportionately more often, for a greater total duration, and for more time per bout, than they initiated grooming behavior. These results suggest that intranasal OXT altered male and female marmosets’ stimulus properties in such a way as to increase the amount of grooming behavior that females received from their

  12. Activity in the human superior colliculus relating to endogenous saccade preparation and execution

    PubMed Central

    Furlan, Michele; Smith, Andrew T.

    2015-01-01

    In recent years a small number of studies have applied functional imaging techniques to investigate visual responses in the human superior colliculus (SC), but few have investigated its oculomotor functions. Here, in two experiments, we examined activity associated with endogenous saccade preparation. We used 3-T fMRI to record the hemodynamic activity in the SC while participants were either preparing or executing saccadic eye movements. Our results showed that not only executing a saccade (as previously shown) but also preparing a saccade produced an increase in the SC hemodynamic activity. The saccade-related activity was observed in the contralateral and to a lesser extent the ipsilateral SC. A second experiment further examined the contralateral mapping of saccade-related activity with a larger range of saccade amplitudes. Increased activity was again observed in both the contralateral and ipsilateral SC that was evident for large as well as small saccades. This suggests that the ipsilateral component of the increase in BOLD is not due simply to small-amplitude saccades producing bilateral activity in the foveal fixation zone. These studies provide the first evidence of presaccadic preparatory activity in the human SC and reveal that fMRI can detect activity consistent with that of buildup neurons found in the deeper layers of the SC in studies of nonhuman primates. PMID:26041830

  13. A sodium afterdepolarization in rat superior colliculus neurons and its contribution to population activity.

    PubMed

    Ghitani, Nima; Bayguinov, Peter O; Basso, Michele A; Jackson, Meyer B

    2016-07-01

    The mammalian superior colliculus (SC) is a midbrain structure that integrates multimodal sensory inputs and computes commands to initiate rapid eye movements. SC neurons burst with the sudden onset of a visual stimulus, followed by persistent activity that may underlie shifts of attention and decision making. Experiments in vitro suggest that circuit reverberations play a role in the burst activity in the SC, but the origin of persistent activity is unclear. In the present study we characterized an afterdepolarization (ADP) that follows action potentials in slices of rat SC. Population responses seen with voltage-sensitive dye imaging consisted of rapid spikes followed immediately by a second distinct depolarization of lower amplitude and longer duration. Patch-clamp recordings showed qualitatively similar behavior: in nearly all neurons throughout the SC, rapid spikes were followed by an ADP. Ionic and pharmacological manipulations along with experiments with current and voltage steps indicated that the ADP of SC neurons arises from Na(+) current that either persists or resurges following Na(+) channel inactivation at the end of an action potential. Comparisons of pharmacological properties and frequency dependence revealed a clear parallel between patch-clamp recordings and voltage imaging experiments, indicating a common underlying membrane mechanism for the ADP in both single neurons and populations. The ADP can initiate repetitive spiking at intervals consistent with the frequency of persistent activity in the SC. These results indicate that SC neurons have intrinsic membrane properties that can contribute to electrical activity that underlies shifts of attention and decision making. PMID:27075543

  14. HEBBIAN MECHANISMS HELP EXPLAIN DEVELOPMENT OF MULTISENSORY INTEGRATION IN THE SUPERIOR COLLICULUS: A NEURAL NETWORK MODEL

    PubMed Central

    Cuppini, C.; Magosso, E.; Rowland, B.; Stein, B.; Ursino, M.

    2013-01-01

    The superior colliculus (SC) integrates relevant sensory information (visual, auditory, somatosensory) from several cortical and subcortical structures, to program orientation responses to external events. However, this capacity is not present at birth, and it is acquired only through interactions with cross-modal events during maturation. Mathematical models provide a quantitative framework, valuable in helping to clarify the specific neural mechanisms underlying the maturation of the multisensory integration in the SC. We extended a neural network model of the adult SC (Cuppini et al. 2010) to describe the development of this phenomenon starting from an immature state, based on known or suspected anatomy and physiology, in which: 1) AES afferents are present but weak, 2) Responses are driven from non-AES afferents, and 3) The visual inputs have a marginal spatial tuning. Sensory experience was modelled by repeatedly presenting modality-specific and cross-modal stimuli. Synapses in the network were modified by simple Hebbian learning rules. As a consequence of this exposure, 1) Receptive fields shrink and come into spatial register, and 2) SC neurons gained the adult characteristic integrative properties: enhancement, depression, and inverse effectiveness. Importantly, the unique architecture of the model guided the development so that integration became dependent on the relationship between the cortical input and the SC. Manipulations of the statistics of the experience during the development changed the integrative profiles of the neurons, and results matched well with the results of physiological studies. PMID:23011260

  15. Adaptive visual and auditory map alignment in barn owl superior colliculus and its neuromorphic implementation.

    PubMed

    Huo, Juan; Murray, Alan; Wei, Dongqing

    2012-09-01

    Adaptation is one of the most important phenomena in biology. A young barn owl can adapt to imposed environmental changes, such as artificial visual distortion caused by wearing a prism. This adjustment process has been modeled mathematically and the model replicates the sensory map realignment of barn owl superior colliculus (SC) through axonogenesis and synaptogenesis. This allows the biological mechanism to be transferred to an artificial computing system and thereby imbue it with a new form of adaptability to the environment. The model is demonstrated in a real-time robot environment. Results of the experiments are compared with and without prism distortion of vision, and show improved adaptability for the robot. However, the computation speed of the embedded system in the robot is slow. A digital and analog mixed signal very-large-scale integration (VLSI) circuit has been fabricated to implement adaptive sensory pathway changes derived from the SC model at higher speed. VLSI experimental results are consistent with simulation results. PMID:24807931

  16. Altered map of visual space in the superior colliculus of mice lacking early retinal waves.

    PubMed

    Mrsic-Flogel, Thomas D; Hofer, Sonja B; Creutzfeldt, Claire; Cloëz-Tayarani, Isabelle; Changeux, Jean-Pierre; Bonhoeffer, Tobias; Hübener, Mark

    2005-07-20

    During the development of the mammalian retinocollicular projection, a coarse retinotopic map is set up by the graded distribution of axon guidance molecules. Subsequent refinement of the initially diffuse projection has been shown to depend on the spatially correlated firing of retinal ganglion cells. In this scheme, the abolition of patterned retinal activity is not expected to influence overall retinotopic organization, but this has not been investigated. We used optical imaging of intrinsic signals to visualize the complete retinotopic map in the superior colliculus (SC) of mice lacking early retinal waves, caused by the deletion of the beta2 subunit of the nicotinic acetylcholine receptor. As expected from previous anatomical studies in the SC of beta2(-/-) mice, regions activated by individual visual stimuli were much larger and had less sharp borders than those in wild-type mice. Importantly, however, we also found systematic distortions of the entire retinotopic map: the map of visual space was expanded anteriorly and compressed posteriorly. Thus, patterned neuronal activity in the early retina has a substantial influence on the coarse retinotopic organization of the SC. PMID:16033902

  17. Direct projections from the dorsal premotor cortex to the superior colliculus in the macaque (macaca mulatta).

    PubMed

    Distler, Claudia; Hoffmann, Klaus-Peter

    2015-11-01

    The dorsal premotor cortex (PMd) is part of the cortical network for arm movements during reach-related behavior. Here we investigate the neuronal projections from the PMd to the midbrain superior colliculus (SC), which also contains reach-related neurons, to investigate how the SC integrates into a cortico-subcortical network responsible for initiation and modulation of goal-directed arm movements. By using anterograde transport of neuronal tracers, we found that the PMd projects most strongly to the deep layers of the lateral part of the SC and the underlying reticular formation corresponding to locations where reach-related neurons have been recorded, and from where descending tectofugal projections arise. A somewhat weaker projection targets the intermediate layers of the SC. By contrast, terminals originating from prearcuate area 8 mainly project to the intermediate layers of the SC. Thus, this projection pattern strengthens the view that different compartments in the SC are involved in the control of gaze and in the control or modulation of reaching movements. The PMD-SC projection assists in the participation of the SC in the skeletomotor system and provides the PMd with a parallel path to elicit forelimb movements.

  18. GATA2 IS REQUIRED FOR MIGRATION AND DIFFERENTIATION OF RETINORECIPIENT NEURONS IN THE SUPERIOR COLLICULUS

    PubMed Central

    Willett, Ryan T.; Greene, Lloyd A.

    2011-01-01

    The superior colliculus (SC)/optic tectum of the dorsal mesencephalon plays a major role in responses to visual input, yet regulation of neuronal differentiation within this layered structure is only partially understood. Here, we show that the zinc finger transcription factor Gata2 is required for normal SC development. Starting at e15 (corresponding to the times at which neurons of the outer and intermediate layers of the SC are generated), Gata2 is transiently expressed in the rat embryonic dorsal mesencephalon within a restricted region between proliferating cells of the ventricular zone and the deepest neuronal layers of the developing SC. The Gata2 positive cells are post-mitotic and lack markers of differentiated neurons, but express markers for immature neuronal precursors including Ascl1 and Pax3/7. In utero electroporation with Gata2 shRNAs at e16 into cells along the dorsal mesencephalic ventricle interferes with their normal migration into the SC and maintains them in a state characterized by retention of Pax3 expression and the absence of mature neuronal markers. Collectively, these findings indicate that Gata2 plays a required role in the transition of post-mitotic neuronal precursor cells of the retinorecipient layers of the SC into mature neurons and that loss of Gata2 arrests them at an intermediate stage of differentiation. PMID:21430145

  19. Brain derived neurotrophic factor keeps pattern electroretinogram from dropping after superior colliculus lesion in mice

    PubMed Central

    Yang, Bin-Bin; Yang, Xu; Ding, Huai-Yu

    2016-01-01

    AIM To determine if brain-derived neurotrophic factor (BDNF) could offer protention to retinal ganglion cells following a superior colliculus (SC) lesion in mice using pattern electroretinogram (PERG) and optical coherence tomography (OCT) as a measures of ganglion cell response and retinal health. METHODS Seven C57BL/6J mice with BDNF protection were tested with PERG and OCT before and after SC lesions. RESULTS Compared with baseline PERG, the amplitude of PERG decreased 11.7% after SC lesions, but not significantly (P>0.05). Through fast Fourier transform (FFT) analysis of the PERGs before and after SC lesions, it was found that dominant frequency of PERGs stayed unchanged, suggesting that the ganglion cells of the retina remained relatively healthy inspite of damage to the ends of the ganglion cell axons. Also, OCT showed no changes in retinal thickness after lesions. CONCLUSION It was concluded that BDNF is essential component of normal retinal and helps retina keeping normal function. While retina lack of BDNF, ex vivo resource of BDNF provides protection to the sick retina. It implies that BDNF is a kind therapeutic neurotrophic factor to retina neurodegeneration diseases, such as glaucoma, age related macular degeneration. PMID:27158604

  20. Spatio-temporal receptive field properties of cells in the rat superior colliculus.

    PubMed

    Prévost, François; Lepore, Franco; Guillemot, Jean-Paul

    2007-04-20

    Although the rat is widely used in neurobehavioural research, the spatio-temporal receptive field properties of neurons in superficial layers of the superior colliculus are relatively unknown. Extracellular recordings were carried out in anesthetized Long Evans rats. Neurons in these layers had simple-like and complex-like receptive fields (RFs). Most cells (67%) had RFs showing band-pass and low-pass spatial frequency (SF) tuning profiles. Spatial band-pass profiles showed low optimal SF (mean=0.03 c/deg), low spatial resolution (mean=0.18 c/deg) and large spatial bandwidths (mean=2.3 octaves). More than two-thirds of the RFs (71%) were selective to orientation and only 11% were clearly direction selective. Nearly two-thirds of cells (68%) had band-pass temporal frequency (TF) tuning profiles with narrow bandwidths (mean=1.7 oct.) whereas the others showed low-pass TF tuning profiles. Temporal band-pass profiles had low optimal TFs (mean=3.5 c/s). Although some cells showed relatively low contrast thresholds (6%), most cells only responded to high contrast values (mean=38.2%). These results show that the spatial resolution of collicular cells is poor and that they respond mainly to highly contrasted moving stimuli.

  1. Dorsolateral Prefrontal Cortex Deactivation in Monkeys Reduces Preparatory Beta and Gamma Power in the Superior Colliculus.

    PubMed

    Chan, Jason L; Koval, Michael J; Womelsdorf, Thilo; Lomber, Stephen G; Everling, Stefan

    2015-12-01

    Cognitive control requires the selection and maintenance of task-relevant stimulus-response associations, or rules. The dorsolateral prefrontal cortex (DLPFC) has been implicated by lesion, functional imaging, and neurophysiological studies to be involved in encoding rules, but the mechanisms by which it modulates other brain areas are poorly understood. Here, the functional relationship of the DLPFC with the superior colliculus (SC) was investigated by bilaterally deactivating the DLPFC while recording local field potentials (LFPs) in the SC in monkeys performing an interleaved pro- and antisaccade task. Event-related LFPs showed differences between pro- and antisaccades and responded prominently to stimulus presentation. LFP power after stimulus onset was higher for correct saccades than erroneous saccades. Deactivation of the DLPFC did not affect stimulus onset related LFP activity, but reduced high beta (20-30 Hz) and high gamma (60-150 Hz) power during the preparatory period for both pro- and antisaccades. Spike rate during the preparatory period was positively correlated with gamma power and this relationship was attenuated by DLPFC deactivation. These results suggest that top-down control of the SC by the DLPFC may be mediated by beta oscillations.

  2. Alignment of multimodal sensory input in the superior colliculus through a gradient-matching mechanism

    PubMed Central

    Phan, An; Yamada, Jena; Feldheim, David A.

    2012-01-01

    The superior colliculus (SC) is a midbrain structure that integrates visual, somatosensory and auditory inputs to direct head and eye movements. Each of these modalities is topographically mapped and aligned with the others to ensure precise behavioral responses to multimodal stimuli. While it is clear that neural activity is instructive for topographic alignment of inputs from the visual cortex (V1) and auditory system with retinal axons in the SC, there is also evidence that activity-independent mechanisms are used to establish topographic alignment between modalities. Here, we show that the topography of the projection from primary somatosensory cortex (S1) to the SC is established during the first postnatal week. Unlike V1-SC projections, the S1-SC projection does not bifurcate when confronted with a duplicated retinocollicular map, showing that retinal input in the SC does not influence the topography of the S1-SC projection. However, S1-SC topography is disrupted in mice lacking ephrins-As, which we find are expressed in graded patterns along with their binding partners, the EphA4 and EphA7, in both S1 and the somatosensory recipient layer of the SC. Taken together, these data support a model in which somatosensory inputs into the SC map topographically and establish alignment with visual inputs in the SC using a gradient-matching mechanism. PMID:22496572

  3. Excitatory Synaptic Feedback from the Motor Layer to the Sensory Layers of the Superior Colliculus

    PubMed Central

    Ghitani, Nima; Bayguinov, Peter O.; Vokoun, Corinne R.; McMahon, Shane

    2014-01-01

    Neural circuits that translate sensory information into motor commands are organized in a feedforward manner converting sensory information into motor output. The superior colliculus (SC) follows this pattern as it plays a role in converting visual information from the retina and visual cortex into motor commands for rapid eye movements (saccades). Feedback from movement to sensory regions is hypothesized to play critical roles in attention, visual image stability, and saccadic suppression, but in contrast to feedforward pathways, motor feedback to sensory regions has received much less attention. The present study used voltage imaging and patch-clamp recording in slices of rat SC to test the hypothesis of an excitatory synaptic pathway from the motor layers of the SC back to the sensory superficial layers. Voltage imaging revealed an extensive depolarization of the superficial layers evoked by electrical stimulation of the motor layers. A pharmacologically isolated excitatory synaptic potential in the superficial layers depended on stimulus strength in the motor layers in a manner consistent with orthodromic excitation. Patch-clamp recording from neurons in the sensory layers revealed excitatory synaptic potentials in response to glutamate application in the motor layers. The location, size, and morphology of responsive neurons indicated they were likely to be narrow-field vertical cells. This excitatory projection from motor to sensory layers adds an important element to the circuitry of the SC and reveals a novel feedback pathway that could play a role in enhancing sensory responses to attended targets as well as visual image stabilization. PMID:24828636

  4. Unilateral eye enucleation in adult rats causes neuronal loss in the contralateral superior colliculus

    PubMed Central

    SMITH, S. A.; BEDI, K. S.

    1997-01-01

    Several studies have reported the morphological changes induced by unilateral enucleation during early neonatal life on the developing visual system. This study has examined cellular changes in the superior colliculi by removal of a single eye in adult rats. Anaesthetised male hooded rats aged 90 d had their right eyes removed. Groups of nonenucleated control and enucleated rats were killed when aged either 150 or 390 d. The brains were removed and both the right and left superior colliculi dissected out. The volume of the stratum griseum superficiale (SGS) within these colliculi was estimated stereologically by light microscopy, as well as the numerical density and total number of neurons within this cell layer. The volume of the cell layer was reduced by about 40% on the side contralateral to the enucleated eye but not on the ipsilateral side at both survival periods examined. The numerical density of neurons within the SGS was unaffected by the enucleation so that the colliculi contralateral to the enucleated eye showed a substantial loss of neurons within this cell layer. This study demonstrates the importance of the retinal ganglion cell input, even in adult animals, for maintaining the viability of neurons in the SGS layer of the superior colliculus. PMID:9183672

  5. Separate visual signals for saccade initiation during target selection in the primate superior colliculus.

    PubMed

    White, Brian J; Munoz, Douglas P

    2011-02-01

    The primary function of the superior colliculus (SC) is to orient the visual system toward behaviorally relevant stimuli defined by features such as color. However, a longstanding view has held that visual activity in the SC arises exclusively from achromatic pathways. Recently, we reported evidence that the primate SC is highly sensitive to signals originating from chromatic pathways, but these signals are delayed relative to luminance signals (White et al., 2009). Here, we describe a functional consequence of this difference in visual arrival time on the processes leading to target selection and saccade initiation. Two rhesus monkeys performed a simple color-singleton selection task in which stimuli carried a chromatic component only (target and distractors were isoluminant with the background, but differed in chromaticity) or a combined chromatic-achromatic component (36% luminance contrast added equally to all stimuli). Although visual responses were delayed in the chromatic-only relative to the combined chromatic-achromatic condition, SC neurons discriminated the target from distractors at approximately the same time provided stimulus chromaticity was held constant. However, saccades were triggered sooner, and with more errors, with the chromatic-achromatic condition, suggesting that luminance signals associated with these stimuli increased the probability of triggering a saccade before the target color was adequately discriminated. These results suggest that separate mechanisms may independently influence the saccadic command in the SC, one linked to the arrival time of pertinent visual signals, and another linked to the output of the visual selection process. PMID:21289164

  6. Activity in the human superior colliculus relating to endogenous saccade preparation and execution.

    PubMed

    Furlan, Michele; Smith, Andrew T; Walker, Robin

    2015-08-01

    In recent years a small number of studies have applied functional imaging techniques to investigate visual responses in the human superior colliculus (SC), but few have investigated its oculomotor functions. Here, in two experiments, we examined activity associated with endogenous saccade preparation. We used 3-T fMRI to record the hemodynamic activity in the SC while participants were either preparing or executing saccadic eye movements. Our results showed that not only executing a saccade (as previously shown) but also preparing a saccade produced an increase in the SC hemodynamic activity. The saccade-related activity was observed in the contralateral and to a lesser extent the ipsilateral SC. A second experiment further examined the contralateral mapping of saccade-related activity with a larger range of saccade amplitudes. Increased activity was again observed in both the contralateral and ipsilateral SC that was evident for large as well as small saccades. This suggests that the ipsilateral component of the increase in BOLD is not due simply to small-amplitude saccades producing bilateral activity in the foveal fixation zone. These studies provide the first evidence of presaccadic preparatory activity in the human SC and reveal that fMRI can detect activity consistent with that of buildup neurons found in the deeper layers of the SC in studies of nonhuman primates.

  7. Spatially selective auditory responses in the superior colliculus of the echolocating bat.

    PubMed

    Valentine, D E; Moss, C F

    1997-03-01

    When a bat approaches a target, it continuously modifies its echolocation sounds and relies on incoming echo information to shape the characteristics of its subsequent sonar cries. In addition, acoustic information about the azimuth and elevation of a sonar target elicits orienting movements of the head and pinnae toward the sound source. This requires a common sensorimotor interface, where echo information is used to guide motor behaviors. Using single-unit neurophysiological methods and free-field auditory stimulation, we present data on biologically relevant specializations in the superior colliculus (SC) of the bat for orientation by sonar. In the bat's SC, two classes of spatially tuned neurons are distinguished by their sensitivity to echoes. One population shows facilitated, delay-tuned responses to pairs of sounds, simulating sonar emissions and echoes. Delay tuning, related to encoding target range, may play a role in guiding motor responses in echolocation, because the bat adjusts its emissions with changes in target distance. The delay-facilitated response depends on the direction of stimulation and on the temporal relationship between the simulated emission and echo in the sound pair, suggesting that this class of neurons represents the location of a target in three dimensions. A second population encodes the target in two dimensions, azimuth and elevation, and does not show a facilitated response to echoes delivered from any locus. Encoding of azimuth and elevation may be important for directing head aim, and this class may function in transforming auditory spatial information into signals used to guide acoustic orientation.

  8. Sub-threshold activation of the superior colliculus drives saccade motor learning

    PubMed Central

    Soetedjo, Robijanto; Fuchs, Albert F.; Kojima, Yoshiko

    2010-01-01

    How the brain learns and maintains accurate precision movements is currently unknown. At times throughout life, rapid gaze shifts (saccades) become inaccurate, but the brain makes gradual adjustments so they again stop on target. Previously, we showed that complex spikes (CSs) in Purkinje cells of the oculomotor cerebellum report the direction and amplitude by which saccades are in error. Anatomical studies indicate that this error signal could originate in the superior colliculus (SC). Here we deliver sub-threshold electrical stimulation of the SC after the saccade lands to signal an apparent error. The size of saccades in the same direction as the simulated error gradually increase; those in the opposite direction decrease. The electrically-adapted saccades endure after stimulation is discontinued, exhibit an adaptation field, can undergo changes in direction and depend on error timing. These electrically-induced adaptations were virtually identical to those produced by the visually-induced adaptations that we report here for comparable visual errors in the same monkeys. Therefore, our experiments reveal that an additional role for the SC in the generation of saccades is to provide a vector error signal that drives dysmetric saccades to adapt. Moreover, the characteristics of the electrically-induced adaptation reflect those of error-related CS activity in the oculomotor cerebellum, suggesting that CS activity serves as the learning signal. We speculate that CS activity may serve as the error signal that drives other kinds of motor learning as well. PMID:19955374

  9. Hebbian mechanisms help explain development of multisensory integration in the superior colliculus: a neural network model.

    PubMed

    Cuppini, C; Magosso, E; Rowland, B; Stein, B; Ursino, M

    2012-12-01

    The superior colliculus (SC) integrates relevant sensory information (visual, auditory, somatosensory) from several cortical and subcortical structures, to program orientation responses to external events. However, this capacity is not present at birth, and it is acquired only through interactions with cross-modal events during maturation. Mathematical models provide a quantitative framework, valuable in helping to clarify the specific neural mechanisms underlying the maturation of the multisensory integration in the SC. We extended a neural network model of the adult SC (Cuppini et al., Front Integr Neurosci 4:1-15, 2010) to describe the development of this phenomenon starting from an immature state, based on known or suspected anatomy and physiology, in which: (1) AES afferents are present but weak, (2) Responses are driven from non-AES afferents, and (3) The visual inputs have a marginal spatial tuning. Sensory experience was modeled by repeatedly presenting modality-specific and cross-modal stimuli. Synapses in the network were modified by simple Hebbian learning rules. As a consequence of this exposure, (1) Receptive fields shrink and come into spatial register, and (2) SC neurons gained the adult characteristic integrative properties: enhancement, depression, and inverse effectiveness. Importantly, the unique architecture of the model guided the development so that integration became dependent on the relationship between the cortical input and the SC. Manipulations of the statistics of the experience during the development changed the integrative profiles of the neurons, and results matched well with the results of physiological studies. PMID:23011260

  10. Isolation and characterization of a novel Helicobacter species, Helicobacter jaachi sp. nov., from common marmosets (Callithrix jaachus)

    PubMed Central

    Shen, Zeli; Feng, Yan; Sheh, Alexander; Everitt, Jeffrey; Bertram, Frederick; Paster, Bruce J.

    2015-01-01

    Purpose-bred common marmosets from domestic sources housed in a US research facility, and used in multiple drug discovery programmes, were noted to have a high incidence of spontaneous inflammatory bowel disease and sporadic cholecystitis and cholangiohepatitis. Inflammatory infiltrates increased in incidence and severity with age. Because Helicobacter spp. have been linked to gastrointestinal diseases, samples from the gastrointestinal tracts of 39 marmosets were screened for Helicobacter spp. by culture and PCR. Helicobacter spp. were frequently detected in marmosets; 28.2 % of the marmosets were positive for a proposed novel species, Helicobacter jaachi sp. nov., by culture, and 48.7 % were positive by Helicobacter genus-specific PCR. Seventeen strains of Helicobacter sp. from 11 marmosets were cultured from various gastrointestinal sites. Older animals (age 6–11 years) had a higher helicobacter prevalence rate (57.1 %) compared with younger animals (age 3–5 years), which had a 27.2 % prevalence rate. Cells of H. jaachi sp. nov. were catalase, urease and oxidase positive and had fusiform morphology, with periplasmic fibres and multiple bipolar, sheathed flagella. All isolates had similar 16S and 23S rRNA sequences, which clustered as representatives of a novel Helicobacter species closely related to ‘Helicobacter sanguini’ (97 %), a species isolated from cotton-top tamarins and ‘Helicobacter callitrichis’ (96 %) isolated previously from the faeces of common marmosets. The whole genome sequence of one of the liver isolates, H. jaachi sp. nov. MIT 09-6949T, had a 1.9 Mb genome length with a 41 mol% DNA G+C content. The type strain of Helicobacter jaachi sp. nov., MIT 09-6949T, has been deposited in the BCCM/LMG Bacteria Collection as LMG 28613T. These findings add to the increasing number of animal species with gastrointestinal disease in which novel enterohepatic Helicobacter spp. have been isolated. PMID:26297446

  11. A foraging advantage for dichromatic marmosets (Callithrix geoffroyi) at low light intensity.

    PubMed

    Caine, Nancy G; Osorio, Daniel; Mundy, Nicholas I

    2010-02-23

    Most New World monkey species have both dichromatic and trichromatic individuals present in the same population. The selective forces acting to maintain the variation are hotly debated and are relevant to the evolution of the 'routine' trichromatic colour vision found in catarrhine primates. While trichromats have a foraging advantage for red food compared with dichromats, visual tasks which dichromats perform better have received less attention. Here we examine the effects of light intensity on foraging success among marmosets. We find that dichromats outperform trichomats when foraging in shade, but not in sun. The simplest explanation is that dichromats pay more attention to achromatic cues than trichromats. However, dichromats did not show a preference for foraging in shade compared with trichromats. Our results reveal several interesting parallels with a recent study in capuchin monkeys (Cebus capucinus), and suggest that dichromat advantage for certain tasks contributes to maintenance of the colour vision polymorphism. PMID:19740895

  12. Human speech- and reading-related genes display partially overlapping expression patterns in the marmoset brain.

    PubMed

    Kato, Masaki; Okanoya, Kazuo; Koike, Taku; Sasaki, Erika; Okano, Hideyuki; Watanabe, Shigeru; Iriki, Atsushi

    2014-06-01

    Language is a characteristic feature of human communication. Several familial language impairments have been identified, and candidate genes for language impairments already isolated. Studies comparing expression patterns of these genes in human brain are necessary to further understanding of these genes. However, it is difficult to examine gene expression in human brain. In this study, we used a non-human primate (common marmoset; Callithrix jacchus) as a biological model of the human brain to investigate expression patterns of human speech- and reading-related genes. Expression patterns of speech disorder- (FoxP2, FoxP1, CNTNAP2, and CMIP) and dyslexia- (ROBO1, DCDC2, and KIAA0319) related genes were analyzed. We found the genes displayed overlapping expression patterns in the ocular, auditory, and motor systems. Our results enhance understanding of the molecular mechanisms underlying language impairments.

  13. Assessment of cognitive and motor deficits in a marmoset model of stroke.

    PubMed

    Marshall, Jonathan W B; Ridley, Rosalind M

    2003-01-01

    The Stroke Therapy Academic Industry Roundtable noted the need for standardized, well-accepted primate models of stroke to help develop both neuroprotective and restorative therapies. One primate model has been developed using the marmoset, a small New World species of monkey, in which long-term functional deficits can be assessed. The surgery and postoperative care of the animals is described, as well as the behavioral tests used to quantify the postoperative disability. The types of deficits seen are illustrated by reference to some of the findings with neuroprotective treatments. Nevertheless, the long-term nature and consistency of the motor deficits make this model ideal for assessing the worth of restorative therapies.

  14. Natural and Anthropogenic Hybridization in Two Species of Eastern Brazilian Marmosets (Callithrix jacchus and C. penicillata).

    PubMed

    Malukiewicz, Joanna; Boere, Vanner; Fuzessy, Lisieux F; Grativol, Adriana D; de Oliveira E Silva, Ita; Pereira, Luiz C M; Ruiz-Miranda, Carlos R; Valença, Yuri M; Stone, Anne C

    2015-01-01

    Animal hybridization is well documented, but evolutionary outcomes and conservation priorities often differ for natural and anthropogenic hybrids. Among primates, an order with many endangered species, the two contexts can be hard to disentangle from one another, which carries important conservation implications. Callithrix marmosets give us a unique glimpse of genetic hybridization effects under distinct natural and human-induced contexts. Here, we use a 44 autosomal microsatellite marker panel to examine genome-wide admixture levels and introgression at a natural C. jacchus and C. penicillata species border along the São Francisco River in NE Brazil and in an area of Rio de Janeiro state where humans introduced these species exotically. Additionally, we describe for the first time autosomal genetic diversity in wild C. penicillata and expand previous C. jacchus genetic data. We characterize admixture within the natural zone as bimodal where hybrid ancestry is biased toward one parental species or the other. We also show evidence that São Francisco River islands are gateways for bidirectional gene flow across the species border. In the anthropogenic zone, marmosets essentially form a hybrid swarm with intermediate levels of admixture, likely from the absence of strong physical barriers to interspecific breeding. Our data show that while hybridization can occur naturally, the presence of physical, even if leaky, barriers to hybridization is important for maintaining species genetic integrity. Thus, we suggest further study of hybridization under different contexts to set well informed conservation guidelines for hybrid populations that often fit somewhere between "natural" and "man-made." PMID:26061111

  15. Long-term fidelity of foraging techniques in common marmosets (Callithrix jacchus).

    PubMed

    Gunhold, Tina; Range, Friederike; Huber, Ludwig; Bugnyar, Thomas

    2015-03-01

    The formation of behavioral traditions has been considered as one of the main building blocks of culture. Numerous studies on social learning in different animal species provide evidence for their capability of successful transmission of information. However, questions concerning the memory and maintenance of this information have received comparably little attention. After the innovation and initial spread of a novel behavior, the behavior should stabilize and be maintained over time. Otherwise, the behavioral pattern might collapse and no tradition formation would be possible. The aim of this study was to investigate long-term preferences in a two-action manipulation task in common marmosets (Callithrix jacchus). Three captive family groups (23 individuals in total) were trained on one of two possible techniques to open a wooden box and gain access to a food reward, by either pulling or pushing a flap door. The training phase took place in a family group setting, while the test phase was conducted individually. Although the subjects could experience the alternative technique during the test sessions, the majority preferentially used the technique learned in the group setting. Moreover, the subjects were re-tested six times over a period of more than four years, in order to examine the fidelity of their preferences. The longest break without exposure the task lasted for 3.5 years. In all tests, the marmosets showed a similar preference as in the first test block shortly after the training. To our knowledge, this is the first lab study that experimentally demonstrates memory and fidelity of experimentally seeded information in a manipulation task over a time period of several years, supporting the assumption that socially learned foraging techniques can lead to relatively stable behavioral traditions. PMID:25231356

  16. The midget-parvocellular pathway of marmoset retina: a quantitative light microscopic study.

    PubMed

    Telkes, Ildiko; Lee, Sammy C S; Jusuf, Patricia R; Grünert, Ulrike

    2008-10-10

    The midget-parvocellular pathway in foveal retina of primates shows a "private line" (one-to-one) connectivity with cone photoreceptors. The connectivity of this pathway outside the fovea is not well understood. Here, we studied the population of OFF midget bipolar cells across the retinae of marmoset monkeys (Callithrix jacchus) by using light microscopy. Cone pedicles were labeled with peanut agglutinin, OFF midget bipolar cells were labeled with antibodies against CD15, and midget ganglion cells were retrogradely labeled from the lateral geniculate nucleus and subsequently photofilled. Each midget bipolar cell contacts a single cone in foveal retina, but outside the fovea midget bipolar cells contact multiple cones: one to two cones at 1 mm ( approximately 8 degrees); three to four cones at 3-4 mm ( approximately 25 degrees); and five or more cones beyond 6 mm (>50 degrees). Throughout this eccentricity range, all medium (M) and long (L) wavelength sensitive cones make similar number of contacts with midget bipolar cells, but short wavelength sensitive (S) cones make little or no contact. By calculating the numerical convergence between midget bipolar and midget ganglion cells, we estimate that midget ganglion cells receive input from up to 25 cones at approximately 5 degrees, and from more than 65 cones at approximately 50 degrees. No obvious differences were seen between the retinae of animals with di- or trichromatic color vision. The finding that the one-to-one connectivity is restricted to the fovea predicts that in marmosets spectral mixing of M/L cone inputs will occur peripheral to 10 degrees of visual angle. PMID:18683219

  17. Imitation as faithful copying of a novel technique in marmoset monkeys.

    PubMed

    Voelkl, Bernhard; Huber, Ludwig

    2007-07-11

    Imitative learning has received great attention due to its supposed role in the development of culture and the cognitive demands it poses on the individual. Evidence for imitation in non-human primate species, therefore, could shed light on the early origins of proto-cultural traits in the primate order. Imitation has been defined as the learning of an act by seeing it done or, more specifically, as the copying of a novel or otherwise improbable act. But despite a century of research and the detection of mirror neurons the empirical basis for this most advanced form of observational learning is weak. Few, if any, studies have shown that the observer has learned the response topography, i.e., the specific action by which the response is made. In an experimental set-up we confronted marmoset monkeys (Callithrix jacchus) with a conspecific model that was previously trained to open a plastic box in a peculiar way. Employing detailed motion analyses we show that the observers precisely copied the movement patterns of the novel action demonstrated by the model. A discriminant analysis classified 13 out of 14 observer movements (92.86%) as model movements and only one as non-observer movement. This evidence of imitation in non-human primates questions the dominant opinion that imitation is a human-specific ability. Furthermore, the high matching degree suggests that marmosets possess the neuronal mechanism to code the actions of others and to map them onto their own motor repertoire, rather than priming existing motor-templates.

  18. Natural and Anthropogenic Hybridization in Two Species of Eastern Brazilian Marmosets (Callithrix jacchus and C. penicillata).

    PubMed

    Malukiewicz, Joanna; Boere, Vanner; Fuzessy, Lisieux F; Grativol, Adriana D; de Oliveira E Silva, Ita; Pereira, Luiz C M; Ruiz-Miranda, Carlos R; Valença, Yuri M; Stone, Anne C

    2015-01-01

    Animal hybridization is well documented, but evolutionary outcomes and conservation priorities often differ for natural and anthropogenic hybrids. Among primates, an order with many endangered species, the two contexts can be hard to disentangle from one another, which carries important conservation implications. Callithrix marmosets give us a unique glimpse of genetic hybridization effects under distinct natural and human-induced contexts. Here, we use a 44 autosomal microsatellite marker panel to examine genome-wide admixture levels and introgression at a natural C. jacchus and C. penicillata species border along the São Francisco River in NE Brazil and in an area of Rio de Janeiro state where humans introduced these species exotically. Additionally, we describe for the first time autosomal genetic diversity in wild C. penicillata and expand previous C. jacchus genetic data. We characterize admixture within the natural zone as bimodal where hybrid ancestry is biased toward one parental species or the other. We also show evidence that São Francisco River islands are gateways for bidirectional gene flow across the species border. In the anthropogenic zone, marmosets essentially form a hybrid swarm with intermediate levels of admixture, likely from the absence of strong physical barriers to interspecific breeding. Our data show that while hybridization can occur naturally, the presence of physical, even if leaky, barriers to hybridization is important for maintaining species genetic integrity. Thus, we suggest further study of hybridization under different contexts to set well informed conservation guidelines for hybrid populations that often fit somewhere between "natural" and "man-made."

  19. Spatial properties of koniocellular cells in the lateral geniculate nucleus of the marmoset Callithrix jacchus

    PubMed Central

    White, Andrew J R; Solomon, Samuel G; Martin, Paul R

    2001-01-01

    The receptive field dimensions, contrast sensitivity and linearity of spatial summation of koniocellular (KC), parvocellular (PC) and magnocellular (MC) cells in the lateral geniculate nucleus (LGN) of 11 adult marmosets were measured using achromatic sinusoidal gratings. The receptive field centre diameter of cells in each (PC, KC and MC) class increases with distance from the fovea. There is substantial overlap in centre size between the three cell classes at any eccentricity, but the PC cells have, on average, the smallest centres and the KC cells have the largest. Some PC and KC cells did not respond at all to the grating stimulus. The contrast sensitivity of the receptive field centre mechanism in KC cells decreases in proportion to the centre area. A similar trend was seen for the surround mechanism. These characteristics are common to PC and MC cells, suggesting that they originate at an early stage of visual processing in the retina. The KC cells showed, in general, lower peak evoked discharge rates than PC or MC cells. The spontaneous discharge rate of KC cells was lower than that of PC cells and similar to that of MC cells. The majority of cells in all divisions of the LGN show linear spatial summation. A few cells did show non-linear spatial summation; these cells were predominantly located in the MC and ventral KC layers. The ventral KC layers below and between the MC layers contain cells with larger and more transiently responding receptive fields than cells in the more dorsal KC layers. We conclude that many of the contrast-dependent spatial properties of cells in the marmoset LGN are common to PC, MC and KC cells. The main difference between KC cells and the other two classes is that there is more variability in their response properties, and they are less responsive to high spatial frequencies. PMID:11389209

  20. Reversal learning in gonadectomized marmosets with and without hormone replacement: are males more sensitive to punishment?

    PubMed

    LaClair, Matthew; Lacreuse, Agnès

    2016-05-01

    This study examined sex differences in executive function in middle-aged gonadectomized marmosets (Callithrix jacchus) with or without hormonal replacement. We tested ten castrated male (mean age 5.5 years) marmosets treated with testosterone cypionate (T, n = 5) or vehicle (n = 5) on Reversal Learning, which contributes to cognitive flexibility, and the Delayed Response task, measuring working memory. Their performance was compared to that of 11 ovariectomized females (mean age = 3.7 years) treated with Silastic capsules filled with 17-β estradiol (E2, n = 6) or empty capsules (n = 5), previously tested on the same tasks (Lacreuse et al. in J Neuroendocrinol 26:296-309, 2014. doi: 10.1111/jne.12147). Behavioral observations were conducted daily. Females exhibited more locomotor behaviors than males. Males and females did not differ in the number of trials taken to reach criterion on the reversals, but males had significantly longer response latencies, regardless of hormone replacement. They also had a greater number of refusals than females. Additionally, both control and T-treated males, but not females, had slower responses on incorrect trials, suggesting that males were making errors due to distraction, lack of motivation or uncertainty. Furthermore, although both males and females had slower responding following an incorrect compared to a correct trial, the sex difference in response latencies was disproportionally large following an incorrect trial. No sex difference was found in the Delayed Response task. Overall, slower response latencies in males than females during Reversal Learning, especially during and following an incorrect trial, may reflect greater sensitivity to punishment (omission of reward) and greater performance monitoring in males, compared to females. Because these differences occurred in gonadectomized animals and regardless of hormone replacement, they may be organized early in life. PMID:26909674

  1. Natural and Anthropogenic Hybridization in Two Species of Eastern Brazilian Marmosets (Callithrix jacchus and C. penicillata)

    PubMed Central

    Malukiewicz, Joanna; Boere, Vanner; Fuzessy, Lisieux F.; Grativol, Adriana D.; de Oliveira e Silva, Ita; Pereira, Luiz C. M.; Ruiz-Miranda, Carlos R.; Valença, Yuri M.; Stone, Anne C.

    2015-01-01

    Animal hybridization is well documented, but evolutionary outcomes and conservation priorities often differ for natural and anthropogenic hybrids. Among primates, an order with many endangered species, the two contexts can be hard to disentangle from one another, which carries important conservation implications. Callithrix marmosets give us a unique glimpse of genetic hybridization effects under distinct natural and human-induced contexts. Here, we use a 44 autosomal microsatellite marker panel to examine genome-wide admixture levels and introgression at a natural C. jacchus and C. penicillata species border along the São Francisco River in NE Brazil and in an area of Rio de Janeiro state where humans introduced these species exotically. Additionally, we describe for the first time autosomal genetic diversity in wild C. penicillata and expand previous C. jacchus genetic data. We characterize admixture within the natural zone as bimodal where hybrid ancestry is biased toward one parental species or the other. We also show evidence that São Francisco River islands are gateways for bidirectional gene flow across the species border. In the anthropogenic zone, marmosets essentially form a hybrid swarm with intermediate levels of admixture, likely from the absence of strong physical barriers to interspecific breeding. Our data show that while hybridization can occur naturally, the presence of physical, even if leaky, barriers to hybridization is important for maintaining species genetic integrity. Thus, we suggest further study of hybridization under different contexts to set well informed conservation guidelines for hybrid populations that often fit somewhere between “natural” and “man-made.” PMID:26061111

  2. Susceptibility of Marmosets (Callithrix jacchus) to Monkeypox Virus: A Low Dose Prospective Model for Monkeypox and Smallpox Disease.

    PubMed

    Mucker, Eric M; Chapman, Jennifer; Huzella, Louis M; Huggins, John W; Shamblin, Joshua; Robinson, Camenzind G; Hensley, Lisa E

    2015-01-01

    Although current nonhuman primate models of monkeypox and smallpox diseases provide some insight into disease pathogenesis, they require a high titer inoculum, use an unnatural route of infection, and/or do not accurately represent the entire disease course. This is a concern when developing smallpox and/or monkeypox countermeasures or trying to understand host pathogen relationships. In our studies, we altered half of the test system by using a New World nonhuman primate host, the common marmoset. Based on dose finding studies, we found that marmosets are susceptible to monkeypox virus infection, produce a high viremia, and have pathological features consistent with smallpox and monkeypox in humans. The low dose (48 plaque forming units) required to elicit a uniformly lethal disease and the extended incubation (preclinical signs) are unique features among nonhuman primate models utilizing monkeypox virus. The uniform lethality, hemorrhagic rash, high viremia, decrease in platelets, pathology, and abbreviated acute phase are reflective of early-type hemorrhagic smallpox.

  3. Sphere-formation culture of testicular germ cells in the common marmoset, a small New World monkey.

    PubMed

    Lin, Zachary Yu-Ching; Hikabe, Orie; Suzuki, Sadafumi; Hirano, Takamasa; Siomi, Haruhiko; Sasaki, Erika; Imamura, Masanori; Okano, Hideyuki

    2016-01-01

    Spermatogonia are specialized cells responsible for continuous spermatogenesis and the production of offspring. Because of this biological property, in vitro culture of spermatogonia provides a powerful methodology to advance reproductive biology and engineering. However, methods for culturing primate spermatogonia are poorly established. We have designed a novel method for culturing spermatogonia in the common marmoset (Callithrix jacchus), a small primate. By using our method with a suite of growth factors, adult marmoset testis-derived germ cells could be cultured in the form of a floating sphere for several weeks. Notably, this method could be applied not only to freshly isolated cells but also to cryopreserved cell stocks. The spheres enriched spermatogonia and early spermatocytes, and could be assembled from a C-KIT(+) spermatogonial population. Techniques for culturing spermatogonia could facilitate increased understanding of primate reproduction as well as the preservation of valuable biomaterials from nonhuman primates.

  4. Multidirectional Instability Accompanying an Inferior Labral Cyst

    PubMed Central

    Ji, Jong-Hun; Kim, Sung-Jae

    2010-01-01

    Paralabral cyst of the shoulder joint can be observed in 2% to 4% of the general population, particularly in men during the third and fourth decade. On average, these cysts measure 10 mm to 20 mm in diameter and are located preferentially on the postero-superior aspect of the glenoid. The MRI has increased the frequency of the diagnosis of paralabral cysts of the shoulder joint. Paralabral cysts of the shoulder joint usually develop in the proximity of the labrum. The relationship between shoulder instability and labral tears is well known, however, the association of shoulder instability with a paralabral cyst is rare. Shoulder instability may cause labral injury or labral injury may cause shoulder instability, and then injured tear develops paralabral cyst. In our patient, the inferior paralabral cyst may be associated with inferior labral tears and instability MRI. PMID:20514270

  5. mRNA expression profile of serotonin receptor subtypes and distribution of serotonergic terminations in marmoset brain

    PubMed Central

    Shukla, Rammohan; Watakabe, Akiya; Yamamori, Tetsuo

    2014-01-01

    To better understand serotonin function in the primate brain, we examined the mRNA expression patterns of all the 13 members of the serotonin receptor (5HTR) family, by in situ hybridization (ISH) and the distribution of serotonergic terminations by serotonin transporter (SERT) protein immunohistochemical analysis. Ten of the 13 5HTRs showed significant mRNA expressions in the marmoset brain. Our study shows several new features of the organization of serotonergic systems in the marmoset brain. (1) The thalamus expressed only a limited number of receptor subtypes compared with the cortex, hippocampus, and other subcortical regions. (2) In the cortex, there are layer-selective and area-selective mRNA expressions of 5HTRs. (3) Highly localized mRNA expressions of 5HT1F and 5HT3A were observed. (4) There was a conspicuous overlap of the mRNA expressions of receptor subtypes known to have somatodendritic localization of receptor proteins with dense serotonergic terminations in the visual cortex, the central lateral (CL) nucleus of the thalamus, the presubiculum, and the medial mammillary nucleus of the hypothalamus. This suggests a high correlation between serotonin availability and receptor expression at these locations. (5) The 5HTRs show differences in mRNA expression pattern between the marmoset and mouse cortices whereas the patterns of both the species were much similar in the hippocampus. We discuss the possible roles of 5HTRs in the marmoset brain revealed by the analysis of their overall mRNA expression patterns. PMID:24904298

  6. Different ovarian responses to potential mates underlie species-specific breeding strategies in common marmoset and Goeldi's monkey.

    PubMed

    Mattle, Franziska M E; Pryce, Christopher R; Anzenberger, Gustl

    2008-08-01

    Callitrichids are cooperative breeders, characterized by obligate twinning, extensive paternal care, and monopolization of reproduction by the dominant female. This is the case in the common marmoset, and in common marmoset groups of more than one adult female, subordinate females are typically acyclic consistent with infertility. However, one callitrichid, Goeldi's monkey, gives birth to singletons and exhibits low paternal care. Given these reproductive traits of Goeldi's monkey, we hypothesized that there would not be suppression of ovarian activity. To test this hypothesis, we applied non-invasive endocrine methods in a step-wise experiment with laboratory groups of both species. In each species, six pairs of sisters were studied alone, in visual contact with an unrelated male and in a polygynous trio with the male, and urine samples were collected for determination of oestrogen titres reflecting ovarian activity. Common marmoset sister pairs exhibited a marked difference in social status: during the study 5 of 6 dominant females conceived but only 1 of 6 subordinate females; the remaining 5 subordinates were acyclic at the end of the study, and instances of ovulation typically resulted in aggression. Goeldi's monkey sister pairs showed no status differences: in all pairs, however, both sisters exhibited a temporary cessation of ovarian cyclicity on trio formation, followed by ovulation and conception. We conclude that these marked differences in ovarian responses reflect the differences in inter-female competition for paternal caregiving resources. In common marmosets with high inter-female competition, suppression of ovulation functions to reduce aggression received by subordinate females; in Goeldi's monkey with low competition, temporary cessation of ovulation could facilitate female choice.

  7. The long-term impact of infant rearing background on the affective state of adult common marmosets (Callithrix jacchus)

    PubMed Central

    Ash, Hayley; Buchanan-Smith, Hannah M.

    2016-01-01

    Early life environment, including temporary family separation, can have a major influence on affective state. Using a battery of tests, the current study compared the performance of adult common marmosets (Callithrix jacchus), reared as infants under 3 different conditions: family-reared twins, family-reared animals from triplet litters where only 2 remain (2stays) and supplementary fed triplets. No significant differences were found in latency to approach and obtain food from a human or a novel object between rearing conditions, suggesting no effect on neophobia. There were no differences in cognitive bias task acquisition time, or proportion of responses to each ambiguous probe. Very minor differences were found in response to the probes, with only supplementary fed marmosets making fewer responses to the middle probe, compared to the probe nearest the rewarded stimuli. Similarly, in a test for anhedonia, no difference was found between rearing conditions in consumption of milkshake at different concentrations. There was just one very small difference in reward motivation, with only supplementary fed triplets demonstrating a lack of preference for milkshake over water at the lowest concentration. This consistent pattern of results suggests that the supplementary feeding of large litters of marmosets at this facility did not have a major effect on welfare, and is unlikely to influence performance in reward-related scientific tasks. Therefore, while family separation is not recommended, this particular practice should be used if it is necessary, such as to reduce infant mortality. Regular positive interactions with humans are also encouraged, to reduce fear and improve welfare of marmosets kept in captivity. PMID:26912940

  8. Development of neurotransmitter parameters in lateral geniculate body, superior colliculus and visual cortex of the albino rat.

    PubMed

    Kvale, I; Fosse, V M; Fonnum, F

    1983-04-01

    The postnatal development of some neurotransmitter parameters was measured in lateral geniculate body, superior colliculus and visual cortex of the rat. The following parameters were studied: (i) high-affinity uptake of L-glutamate or D-aspartate as markers for glutamergic neurons; (ii) high-affinity uptake of GABA, which reflects both glial and neuronal uptake of GABA; (iii) HA beta-alanine uptake as a marker for accumulation of GABA in glial structures; (iv) activity of glutamic acid decarboxylase which reflects GABAergic neurons; and (v) activity of choline acetyltransferase as a cholinergic marker. Km and Vmax were determined for high-affinity uptake of glutamate and GABA in newborn and adult animals. The possible glial influence on the uptake during development is discussed. In lateral geniculate body and visual cortex the HA glutamate uptake showed increasing activity from birth to adulthood, whereas in superior colliculus, the uptake was higher at birth, reaching a small significant peak after 12 days of age, and was then reduced to adult level. Km showed no such change between neonatal and adult animals. At birth, high-affinity GABA-uptake was similar to the adult level in superior colliculus and lateral geniculate body. In visual cortex, the uptake of GABA was 50% of adults. However, on day 15, the GABA uptake showed 2 to 3-fold higher activity in all regions when compared to adult level. Km for GABA uptake in neonatals and adults differed only in lateral geniculate body. High affinity uptake of beta-alanine was 50-80% lower in adults than in newborn rats. Glutamate decarboxylase activity, however, increased continuously in all 3 regions examined. This was true also for choline acetyltransferase.

  9. Detection of fruit by the Cerrado's marmoset (Callithrix penicillata): modeling color signals for different background scenarios and ambient light intensities.

    PubMed

    Perini, Eduardo Sosti; Pessoa, Valdir Filgueiras; Pessoa, Daniel Marques de Almeida

    2009-04-01

    Among placental mammals, only primates have trichromatic color vision, however this is not a uniform condition. Under different genetic status, Old World monkeys have routine trichromacy, while New World monkeys show a visual polymorphism, characterized by obligatory male dichromacy. The ecological role of this genetic difference still remains unclear, but some studies show that dichromats and trichromats appear to have different abilities in detecting colored targets against a background of leaves. The Cerrado's marmoset (Callithrix penicillata) is known to forage in brightly illuminated (savanna-like vegetation) and dimly illuminated (forests) environments, exploiting a high amount of dark fruits. Hence, it seems to be a good model for studying the differential advantages enjoyed by each color vision phenotype under natural conditions. Our aim was to verify how the different phenotypes of Cerrado's marmoset detect components of their diet, evaluating the existence of differential phenotype advantages. Under two different light conditions, visual signals of naturally consumed fruits were modeled against different backgrounds scenarios. Even though dichromats and trichromats appear to be equally suited for tasks involving fruit detection, phenotype differential advantages are observed in this marmoset. In many conditions trichromats are predicted to perform better than dichromats, but under low ambient light dichromats manage to outperform trichromats in some scenarios. Phenotypes that carry widely spaced and longer M/L pigments enjoy the most advantage. These differential performances of trichromatic phenotypes, together with overdominance selection, seem to explain the maintenance of the tri-allelic system found in callitrichids. PMID:19296489

  10. Effect of monocular deprivation on NMDAR1 immunostaining in ocular dominance columns of the marmoset Callithrix jacchus.

    PubMed

    Fonta, C; Chappert, C; Imbert, M

    2000-01-01

    We previously showed that immunoreactivity to N-Methyl-D-aspartate (NMDA) receptors in primary visual cortex of Callithrix jacchus is regulated by visual activity during the second and third postnatal months (Fonta et al., 1997). The purpose of the present study was to show that the columnar pattern of high and low NMDAR1 immunoreactivity observed in monocularly deprived animals corresponds to ocular dominance columns linked to the nondeprived and deprived eye, respectively. We compared cortical distribution of NMDAR1 receptors and the projection zones of thalamic afferents, revealed by transneuronal transport of tritiated proline, in 2-month-old, either monocularly deprived or control, marmosets. The data show that ocular dominance columns exist in 2-month-old marmosets and that a 2-week monocular deprivation by means of eyelid suture leads to a modification of the thalamo-cortical afferents organization. Experiments of neuronal tracing and immunohistochemistry performed on the same animals demonstrated that cortical domains with decreased NMDAR1 level correspond to the deprived eye columns. These investigations, coupled to the previous results, strongly suggest that the NMDA receptors, regulated by visual activity, are involved in the refining of ocular dominance columns in the primary visual cortex of juvenile marmoset.

  11. Evidence for altered monoamine activity and emotional and cognitive disturbance in marmoset monkeys exposed to early life stress.

    PubMed

    Pryce, Christopher R; Dettling, Andrea; Spengler, Marianne; Spaete, Corinne; Feldon, Joram

    2004-12-01

    In common marmoset monkeys (Callithrix jacchus, order Primates), infants aged 2-28 days were deprived of parental care for 30-120 min/day in order to investigate the long-term effects of this neglect-stress model on affect and cognition in a primate species. Basal morning levels of urinary cortisol across the first year of life were unaffected in early deprived marmosets relative to their sibling controls. Basal morning levels of urinary dopamine were chronically increased. This peripheral increase in dopamine activity could represent a marker for central dopamine hyperactivity. Certainly, subadult early deprived marmosets exhibited performance deficits in two dopamine-regulated neuropsychological tasks. They demonstrated: (1) impaired behavioral inhibition in an object reaching with detour task, exhibiting significantly more nonreinforced forward reaches to a reward visible inside a cube that could only be retrieved through an opening to the side of the cube; and (2) impaired reversal learning in a two-way discrimination task based on visual icons presented on a touch-sensitive computer screen. These findings provide further evidence for the relevance of this novel primate model of parent-infant neglect to the environmental causes and mechanisms of human developmental psychopathology.

  12. Social Effects via Olfactory Sensory Stimuli on Reproductive Function and Dysfunction in Cooperative Breeding Marmosets and Tamarins

    PubMed Central

    Ziegler, Toni E.

    2012-01-01

    Most primates are social species whose reproduction is influenced by their social relationships. The cotton-top tamarin, Saguinus oedipus, and the common marmoset, Callithrix jacchus, are cooperative breeding species where the family structure alters reproductive function in many ways. While primates receive social effects on reproduction via all sensory stimuli, the marmosets and tamarins are particularly influenced by olfactory/chemosensory stimuli. The olfactory sensory processing is the ‘social glue’ that keeps the family together. This review describes a number of studies using the marmosets and tamarins at the University of Wisconsin to demonstrate how odor cues are used for altering reproductive function and dysfunction. Several key studies will be discussed to show the role of odor signaling of the female reproductive state. The suppressive effects of odors are mediated by priming odors and can cause a suppressive influence on ovulation in young females via their mother’s scents. Additionally, odor cues from the infant function as priming odors to ensure that fathers and mothers are present and receptive to their parental care duties. Neural pathways occur via the processing of priming odors that consequently stimulate alterations in the behavioral and endocrine response to the stimuli. The dynamics of the cooperative breeding system ensure that offspring have essential needs met and that they develop in a family environment. Olfactory communication plays a key role in maintenance of the social system of Callitrichid monkeys. PMID:22890774

  13. Detection of fruit by the Cerrado's marmoset (Callithrix penicillata): modeling color signals for different background scenarios and ambient light intensities.

    PubMed

    Perini, Eduardo Sosti; Pessoa, Valdir Filgueiras; Pessoa, Daniel Marques de Almeida

    2009-04-01

    Among placental mammals, only primates have trichromatic color vision, however this is not a uniform condition. Under different genetic status, Old World monkeys have routine trichromacy, while New World monkeys show a visual polymorphism, characterized by obligatory male dichromacy. The ecological role of this genetic difference still remains unclear, but some studies show that dichromats and trichromats appear to have different abilities in detecting colored targets against a background of leaves. The Cerrado's marmoset (Callithrix penicillata) is known to forage in brightly illuminated (savanna-like vegetation) and dimly illuminated (forests) environments, exploiting a high amount of dark fruits. Hence, it seems to be a good model for studying the differential advantages enjoyed by each color vision phenotype under natural conditions. Our aim was to verify how the different phenotypes of Cerrado's marmoset detect components of their diet, evaluating the existence of differential phenotype advantages. Under two different light conditions, visual signals of naturally consumed fruits were modeled against different backgrounds scenarios. Even though dichromats and trichromats appear to be equally suited for tasks involving fruit detection, phenotype differential advantages are observed in this marmoset. In many conditions trichromats are predicted to perform better than dichromats, but under low ambient light dichromats manage to outperform trichromats in some scenarios. Phenotypes that carry widely spaced and longer M/L pigments enjoy the most advantage. These differential performances of trichromatic phenotypes, together with overdominance selection, seem to explain the maintenance of the tri-allelic system found in callitrichids.

  14. Distribution of vasopressin and oxytocin binding sites in the brain and upper spinal cord of the common marmoset.

    PubMed

    Schorscher-Petcu, Ara; Dupré, Anouk; Tribollet, Eliane

    2009-09-25

    The aim of this study was to label selectively and to map central vasopressin (AVP) and oxytocin (OT) binding sites in the common marmoset. [(125)I]VPA, a compound selective in rodents and human for the AVP V(1a) receptor, yielded the same labeling pattern as [(3)H]AVP, thus suggesting that most AVP receptors present in the marmoset brain are of the V(1a) subtype. Numerous areas exhibited AVP binding sites, among which the olfactory bulb, the accumbens nucleus, the bed nucleus of the stria terminalis, the hypothalamic suprachiasmatic, arcuate and ventromedial nuclei, the medial amygdaloid nucleus, the nucleus of the solitary tract and the cerebral cortex. Binding sites for [(125)I]OTA, a selective OT receptor antagonist in rat and human, were markedly less abundant than [(125)I]VPA ones, and, to a few exceptions, expressed in different areas. Neither AVP, nor OT binding sites were detected in the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei identified by neurophysin immunoreactivity. Marked species-related differences were observed in the distribution of both AVP and OT binding sites. Altogether, our data provide a morphological basis to investigate the function of central AVP and OT in the marmoset. PMID:19539696

  15. Neuronal correlates of attention and its disengagement in the superior colliculus of rat

    PubMed Central

    Ngan, Nguyen H.; Matsumoto, Jumpei; Takamura, Yusaku; Tran, Anh H.; Ono, Taketoshi; Nishijo, Hisao

    2015-01-01

    Orienting attention to a new target requires prior disengagement of attention from the current focus. Previous studies indicate that the superior colliculus (SC) plays an important role in attention. However, recordings of responses of SC neurons during attentional disengagement have not yet been reported. Here, we analyzed rat SC neuronal activity during performance of an attention-shift task with and without disengagement. In this task, conditioned stimuli (CSs; right and/or left light-flash or sound) were sequentially presented. To obtain an intracranial self-stimulation reward, rats were required to lick a spout when an infrequent conditioned stimulus appeared (reward trials). In the disengagement reward trials, configural stimuli consisting of an infrequent stimulus and frequent stimulus in the former trials were presented; in the non-disengagement reward trials, only an infrequent stimulus was presented. Of the 186 SC neurons responding to the CSs, 41 showed stronger responses to the CSs in the disengagement reward trials than in the non-disengagement reward trials (disengagement-related neurons). Furthermore, lick latencies in the disengagement reward trials were negatively correlated with response magnitudes to the CSs in half of the disengagement-related neurons. These disengagement-related neurons were located mainly in the deep layers of the SC. Another 70 SC neurons responded to the CSs in both disengagement and non-disengagement reward trials, suggesting that these neurons were involved in attention engagement. Our results suggest complementary mechanisms of attentional shift based on two subpopulations of neurons in the SC. PMID:25741252

  16. Molecular features distinguish ten neuronal types in the mouse superficial superior colliculus.

    PubMed

    Byun, Haewon; Kwon, Soohyun; Ahn, Hee-Jeong; Liu, Hong; Forrest, Douglas; Demb, Jonathan B; Kim, In-Jung

    2016-08-01

    The superior colliculus (SC) is a midbrain center involved in controlling head and eye movements in response to inputs from multiple sensory modalities. Visual inputs arise from both the retina and visual cortex and converge onto the superficial layer of the SC (sSC). Neurons in the sSC send information to deeper layers of the SC and to thalamic nuclei that modulate visually guided behaviors. Presently, our understanding of sSC neurons is impeded by a lack of molecular markers that define specific cell types. To better understand the identity and organization of sSC neurons, we took a systematic approach to investigate gene expression within four molecular families: transcription factors, cell adhesion molecules, neuropeptides, and calcium binding proteins. Our analysis revealed 12 molecules with distinct expression patterns in mouse sSC: cadherin 7, contactin 3, netrin G2, cadherin 6, protocadherin 20, retinoid-related orphan receptor β, brain-specific homeobox/POU domain protein 3b, Ets variant gene 1, substance P, somatostatin, vasoactive intestinal polypeptide, and parvalbumin. Double labeling experiments, by either in situ hybridization or immunostaining, demonstrated that the 12 molecular markers collectively define 10 different sSC neuronal types. The characteristic positions of these cell types divide the sSC into four distinct layers. The 12 markers identified here will serve as valuable tools to examine molecular mechanisms that regulate development of sSC neuronal types. These markers could also be used to examine the connections between specific cell types that form retinocollicular, corticocollicular, or colliculothalamic pathways. J. Comp. Neurol. 524:2300-2321, 2016. © 2016 Wiley Periodicals, Inc.

  17. Neural correlates of target selection for reaching movements in superior colliculus

    PubMed Central

    McPeek, Robert M.

    2014-01-01

    We recently demonstrated that inactivation of the primate superior colliculus (SC) causes a deficit in target selection for arm-reaching movements when the reach target is located in the inactivated field (Song JH, Rafal RD, McPeek RM. Proc Natl Acad Sci USA 108: E1433–E1440, 2011). This is consistent with the notion that the SC is part of a general-purpose target selection network beyond eye movements. To understand better the role of SC activity in reach target selection, we examined how individual SC neurons in the intermediate layers discriminate a reach target from distractors. Monkeys reached to touch a color oddball target among distractors while maintaining fixation. We found that many SC neurons robustly discriminate the goal of the reaching movement before the onset of the reach even though no saccade is made. To identify these cells in the context of conventional SC cell classification schemes, we also recorded visual, delay-period, and saccade-related responses in a delayed saccade task. On average, SC cells that discriminated the reach target from distractors showed significantly higher visual and delay-period activity than nondiscriminating cells, but there was no significant difference in saccade-related activity. Whereas a majority of SC neurons that discriminated the reach target showed significant delay-period activity, all nondiscriminating cells lacked such activity. We also found that some cells without delay-period activity did discriminate the reach target from distractors. We conclude that the majority of intermediate-layer SC cells discriminate a reach target from distractors, consistent with the idea that the SC contains a priority map used for effector-independent target selection. PMID:25505107

  18. Defense-like behaviors evoked by pharmacological disinhibition of the superior colliculus in the primate

    PubMed Central

    DesJardin, Jacqueline T.; Holmes, Angela L.; Forcelli, Patrick A.; Cole, Claire E.; Gale, John T.; Wellman, Laurie L.; Gale, Karen; Malkova, Ludise

    2012-01-01

    Stimulation of the intermediate and deep layers of superior colliculus (DLSC) in rodents evokes both tracking/pursuit (approach) and avoidance/flight (defensive) responses (Dean et al., 1989). These two classes of response are subserved by distinct output projections associated with lateral (approach) and medial (defensive) DLSC (Comoli et al., 2012). In nonhuman primates, DLSC has been examined only with respect to orienting/approach behaviors, especially eye movements, however, defense-like behaviors have not been reported. Here we examined the profile of behavioral responses to the activation of DLSC by unilateral intracerebral infusions of the GABAA receptor antagonist, bicuculline methiodide (BIC), in nine freely moving macaques. Across animals, the most consistently evoked behavior was cowering (all animals), followed by increased vocalization and escape-like behaviors (seven animals), and attack of objects (three animals). The effects of BIC were dose-dependent within the range 2.5-14nmol (threshold dose of 4.6nmol). The behaviors and their latency to onset did not vary across different infusion sites within DLSC. Cowering and escape-like behaviors resembled the defense-like responses reported after DLSC stimulation in rats, but in the macaques these responses were evoked from both medial and lateral sites within DLSC. Our findings are unexpected in the context of an earlier theoretical perspective (Dean et al., 1989) that emphasized a preferential role of the primate DLSC for approach rather than defensive responses. Our data provide the first evidence for induction of defense-like behaviors by activation of DLSC in monkeys, suggesting that the role of DLSC in responding to threats is conserved across species. PMID:23283329

  19. Whisker motor cortex reorganization after superior colliculus output suppression in adult rats.

    PubMed

    Veronesi, Carlo; Maggiolini, Emma; Franchi, Gianfranco

    2013-10-01

    The effect of unilateral superior colliculus (SC) output suppression on the ipsilateral whisker motor cortex (WMC) was studied at different time points after tetrodotoxin and quinolinic acid injections, in adult rats. The WMC output was assessed by mapping the movement evoked by intracortical microstimulation (ICMS) and by recording the ICMS-evoked electromyographic (EMG) responses from contralateral whisker muscles. At 1 h after SC injections, the WMC showed: (i) a strong decrease in contralateral whisker sites, (ii) a strong increase in ipsilateral whisker sites and in ineffective sites, and (iii) a strong increase in threshold current values. At 6 h after injections, the WMC size had shrunk to 60% of the control value and forelimb representation had expanded into the lateral part of the normal WMC. Thereafter, the size of the WMC recovered, returning to nearly normal 12 h later (94% of control) and persisted unchanged over time (1-3 weeks). The ICMS-evoked EMG response area decreased at 1 h after SC lesion and had recovered its baseline value 12 h later. Conversely, the latency of ICMS-evoked EMG responses had increased by 1 h and continued to increase for as long as 3 weeks following the lesion. These findings provide physiological evidence that SC output suppression persistently withdrew the direct excitatory drive from whisker motoneurons and induced changes in the WMC. We suggest that the changes in the WMC are a form of reversible short-term reorganization that is induced by SC lesion. The persistent latency increase in the ICMS-evoked EMG response suggested that the recovery of basic WMC excitability did not take place with the recovery of normal explorative behaviour. PMID:23895333

  20. The superior colliculus is sensitive to gestalt-like stimulus configuration in hemispherectomy patients.

    PubMed

    Georgy, Loraine; Celeghin, Alessia; Marzi, Carlo A; Tamietto, Marco; Ptito, Alain

    2016-08-01

    Patients with cortical blindness following a lesion to the primary visual cortex (V1) may retain nonconscious visual abilities (blindsight). One intriguing, though largely unexplored question, is whether nonconscious vision in the blind hemifield of hemianopic patients can be sensitive to higher-order perceptual organization, and which V1-independent structure underlies such effect. To answer this question, we tested two rare hemianopic patients who had undergone hemispherectomy, and in whom the only post-chiasmatic visual structure left intact in the same side of the otherwise damaged hemisphere was the superior colliculus (SC). By using a variant of the redundant target effect (RTE), we presented single dots, patterns composed by the same dots organized in quadruple gestalt-like configurations, or patterns of four dots arranged in random configurations, either singly to the intact visual hemifield or bilaterally to both hemifields. As reported in a number of prior studies on blindsight patients, we found that bilateral stimulation yielded faster reaction times (RTs) than single stimulation of the intact field for all conditions (i.e., there was an implicit RTE). In addition to this effect, both patients showed a further speeding up of RTs when the gestalt-like, but not the random shape, quadruple patterns were projected to their blind hemifield during bilateral stimulation. Because other retino-recipient subcortical and cortical structures in the damaged hemisphere are absent, the SC on the lesioned side seems solely responsible for such an effect. The present results provide initial support to the notion that nonconscious vision might be sensitive to perceptual organization and stimulus configuration through the pivotal contribution of the SC, which can enhance the processing of gestalt-like or structured stimuli over meaningless or randomly assembled ones and translate them into facilitatory motor outputs.

  1. Spatial interactions in the superior colliculus predict saccade behavior in a neural field model.

    PubMed

    Marino, Robert A; Trappenberg, Thomas P; Dorris, Michael; Munoz, Douglas P

    2012-02-01

    During natural vision, eye movements are dynamically controlled by the combinations of goal-related top-down (TD) and stimulus-related bottom-up (BU) neural signals that map onto objects or locations of interest in the visual world. In primates, both BU and TD signals converge in many areas of the brain, including the intermediate layers of the superior colliculus (SCi), a midbrain structure that contains a retinotopically coded map for saccades. How TD and BU signals combine or interact within the SCi map to influence saccades remains poorly understood and actively debated. It has been proposed that winner-take-all competition between these signals occurs dynamically within this map to determine the next location for gaze. Here, we examine how TD and BU signals interact spatially within an artificial two-dimensional dynamic winner-take-all neural field model of the SCi to influence saccadic RT (SRT). We measured point images (spatially organized population activity on the SC map) physiologically to inform the TD and BU model parameters. In this model, TD and BU signals interacted nonlinearly within the SCi map to influence SRT via changes to the (1) spatial size or extent of individual signals, (2) peak magnitude of individual signals, (3) total number of competing signals, and (4) the total spatial separation between signals in the visual field. This model reproduced previous behavioral studies of TD and BU influences on SRT and accounted for multiple inconsistencies between them. This is achieved by demonstrating how, under different experimental conditions, the spatial interactions of TD and BU signals can lead to either increases or decreases in SRT. Our results suggest that dynamic winner-take-all modeling with local excitation and distal inhibition in two dimensions accurately reflects both the physiological activity within the SCi map and the behavioral changes in SRT that result from BU and TD manipulations. PMID:21942761

  2. Adult plasticity in multisensory neurons: Short-term experience-dependent changes in the superior colliculus

    PubMed Central

    Yu, Liping; Stein, Barry E.; Rowland, Benjamin A.

    2010-01-01

    Multisensory neurons in the superior colliculus (SC) have the capability to integrate signals that belong to the same event, despite being conveyed by different senses. They develop this capability during early life as experience is gained with the statistics of cross-modal events. These adaptations prepare the SC to deal with the cross-modal events that are likely to be encountered throughout life. Here we found that neurons in the adult SC can also adapt to experience with sequentially-ordered cross-modal (visual-auditory or auditory-visual) cues, and that they do so over short periods of time (minutes), as if adapting to a particular stimulus configuration. This short-term plasticity was evident as a rapid increase in the magnitude and duration of responses to the first stimulus, and a shortening of the latency and increase in magnitude of the responses to the second stimulus when they are presented in sequence. The result was that the two responses appeared to merge. These changes were stable in the absence of experience with competing stimulus configurations, outlasted the exposure period, and could not be induced by equivalent experience with sequential within-modal (visual-visual or auditory-auditory) stimuli. A parsimonious interpretation is that the additional SC activity provided by the second stimulus became associated with, and increased the potency of, the afferents responding to the preceding stimulus. This interpretation is consistent with the principle of spike-timing dependent plasticity (STDP), which may provide the basic mechanism for short term or long term plasticity and be operative in both the adult and neonatal SC. PMID:20016107

  3. Shared and distinct retinal input to the mouse superior colliculus and dorsal lateral geniculate nucleus

    PubMed Central

    Ellis, Erika M.; Gauvain, Gregory; Sivyer, Benjamin

    2016-01-01

    The mammalian retina conveys the vast majority of information about visual stimuli to two brain regions: the dorsal lateral geniculate nucleus (dLGN) and the superior colliculus (SC). The degree to which retinal ganglion cells (RGCs) send similar or distinct information to the two areas remains unclear despite the important constraints that different patterns of RGC input place on downstream visual processing. To resolve this ambiguity, we injected a glycoprotein-deficient rabies virus coding for the expression of a fluorescent protein into the dLGN or SC; rabies virus labeled a smaller fraction of RGCs than lipophilic dyes such as DiI but, crucially, did not label RGC axons of passage. Approximately 80% of the RGCs infected by rabies virus injected into the dLGN were colabeled with DiI injected into the SC, suggesting that many dLGN-projecting RGCs also project to the SC. However, functional characterization of RGCs revealed that the SC receives input from several classes of RGCs that largely avoid the dLGN, in particular RGCs in which 1) sustained changes in light intensity elicit transient changes in firing rate and/or 2) a small range of stimulus sizes or temporal fluctuations in light intensity elicit robust activity. Taken together, our results illustrate several unexpected asymmetries in the information that the mouse retina conveys to two major downstream targets and suggest that differences in the output of dLGN and SC neurons reflect, at least in part, differences in the functional properties of RGCs that innervate the SC but not the dLGN. PMID:27169509

  4. Neuronal responses to face-like and facial stimuli in the monkey superior colliculus

    PubMed Central

    Nguyen, Minh Nui; Matsumoto, Jumpei; Hori, Etsuro; Maior, Rafael Souto; Tomaz, Carlos; Tran, Anh H.; Ono, Taketoshi; Nishijo, Hisao

    2014-01-01

    The superficial layers of the superior colliculus (sSC) appear to function as a subcortical visual pathway that bypasses the striate cortex for the rapid processing of coarse facial information. We investigated the responses of neurons in the monkey sSC during a delayed non-matching-to-sample (DNMS) task in which monkeys were required to discriminate among five categories of visual stimuli [photos of faces with different gaze directions, line drawings of faces, face-like patterns (three dark blobs on a bright oval), eye-like patterns, and simple geometric patterns]. Of the 605 sSC neurons recorded, 216 neurons responded to the visual stimuli. Among the stimuli, face-like patterns elicited responses with the shortest latencies. Low-pass filtering of the images did not influence the responses. However, scrambling of the images increased the responses in the late phase, and this was consistent with a feedback influence from upstream areas. A multidimensional scaling (MDS) analysis of the population data indicated that the sSC neurons could separately encode face-like patterns during the first 25-ms period after stimulus onset, and stimulus categorization developed in the next three 25-ms periods. The amount of stimulus information conveyed by the sSC neurons and the number of stimulus-differentiating neurons were consistently higher during the 2nd to 4th 25-ms periods than during the first 25-ms period. These results suggested that population activity of the sSC neurons preferentially filtered face-like patterns with short latencies to allow for the rapid processing of coarse facial information and developed categorization of the stimuli in later phases through feedback from upstream areas. PMID:24672448

  5. Sharper, Stronger, Faster Upper Visual Field Representation in Primate Superior Colliculus.

    PubMed

    Hafed, Ziad M; Chen, Chih-Yang

    2016-07-11

    Visually guided behavior in three-dimensional environments entails handling immensely different sensory and motor conditions across retinotopic visual field locations: peri-personal ("near") space is predominantly viewed through the lower retinotopic visual field (LVF), whereas extra-personal ("far") space encompasses the upper visual field (UVF). Thus, when, say, driving a car, orienting toward the instrument cluster below eye level is different from scanning an upcoming intersection, even with similarly sized eye movements. However, an overwhelming assumption about visuomotor circuits for eye-movement exploration, like those in the primate superior colliculus (SC), is that they represent visual space in a purely symmetric fashion across the horizontal meridian. Motivated by ecological constraints on visual exploration of far space, containing small UVF retinal-image features, here we found a large, multi-faceted difference in the SC's representation of the UVF versus LVF. Receptive fields are smaller, more finely tuned to image spatial structure, and more sensitive to image contrast for neurons representing the UVF. Stronger UVF responses also occur faster. Analysis of putative synaptic activity revealed a particularly categorical change when the horizontal meridian is crossed, and our observations correctly predicted novel eye-movement effects. Despite its appearance as a continuous layered sheet of neural tissue, the SC contains functional discontinuities between UVF and LVF representations, paralleling a physical discontinuity present in cortical visual areas. Our results motivate the recasting of structure-function relationships in the visual system from an ecological perspective, and also exemplify strong coherence between brain-circuit organization for visually guided exploration and the nature of the three-dimensional environment in which we function. PMID:27291052

  6. The morphology of optic tract axons arborizing in the superior colliculus of the hamster.

    PubMed

    Sachs, G M; Schneider, G E

    1984-12-01

    Single axons innervating the superficial layers of the hamster's superior colliculus (SC) were visualized using an HRP-filling technique. Five types of axons were distinguished. Experiments involving the removal of retinal and/or cortical input showed that three of these axon types originated in the contralateral retina with the fourth type most likely originating in the visual cortex. The origin of the fifth type, a widely branched varicose axon, is apparently subcortical. The two major types of presumed retinotectal axons (types U and L1) project to the stratum griseum superficiale (SGS) in a bilaminar pattern. Type U axons take relatively direct paths from the layer of optic fibers to form dense terminal arbors in the upper half of the SGS. Terminal fields for type U fibers showed fairly consistent dimensions. Their rostrocaudal extent ranged from 90 micron to 190 micron, averaging about 120 micron. Type L1 axons were thicker than type U axons and terminated in deeper regions of the SGS and in the stratum opticum (SO). Single axons of this type often gave rise to multiple branches which took separate, circuitous paths to a common terminal field. Terminal fields for type L1 axons varied more in extent than did type U fields, but 58% of them had fields 90-150 micron in extent. Each of the axon types found can be related to previous studies of populations of tectal afferents. The two major types of retinofugal axons fit a scheme of parallel ascending pathways. The findings also have interesting implications for the study of axonal development.

  7. Maxillary antral lavage using inferior meatal cannula anaesthesia.

    PubMed

    Mochloulis, G; Hern, J D; Hollis, L J; Tolley, N S

    1996-08-01

    Antral puncture and lavage through the inferior meatus is a minor but common otolaryngological procedure, usually performed under local anaesthesia. We describe a new method of introducing local anaesthetic into the inferior meatus, via the use of a soft intravenous cannula connected to a syringe containing 10 per cent cocaine paste. We have called this new technique inferior meatal cannula anaesthesia (IMCA).

  8. Inferior sinus venosus defects: anatomic features and echocardiographic correlates.

    PubMed

    Plymale, Jennifer; Kolinski, Kellen; Frommelt, Peter; Bartz, Peter; Tweddell, James; Earing, Michael G

    2013-02-01

    Inferior sinus venosus defects (SVDs) are rare imperfections located in the inferior portion of the atrial septum, leading to an overriding inferior vena cava (IVC) and an interatrial connection. These defects have increased risk of anomalous pulmonary venous return (PAPVR) and often are confused with secundum atrial septal defects (ASDs) with inferior extension. The authors sought to review their experience with inferior SVDs and to establish at their institution an echocardiographic definition that differentiates inferior SVDs from secundum ASDs with inferior extension. The study identified 161 patients 1.5 to 32 years of age who had undergone repair of a secundum ASD with inferior extension or inferior SVD over the preceding 10 years. All surgical notes, preoperative transthoracic echocardiograms (TTEs), and preoperative transesophageal echocardiograms (TEEs) were reviewed. Based on the surgical notes, 147 patients were classified as having a secundum ASD (147/161, 91 %) and 14 patients (9 %) as having an inferior SVD. The study identified PAPVR in 7 % (1/14) of the patients with inferior SVDs and 3.5 % (5/14) of the patients with secundum ASDs. Surgical diagnosis and preoperative TTE correlated for 143 (89 %) of the 161 patients. Using a strict anatomic and echocardiographic definition with a blinded observer, the majority of the defects (14/18, 78 %) were reclassified correctly after review of their TTE images, and 100 % of the defects were correctly reclassified after TEE image review. Accurate diagnosis of inferior SVDs remains challenging. The data from this study demonstrate that use of a strict anatomic and echocardiographic definition (a defect that originates in the mouth of the IVC and continues into the inferoposterior border of the left atrium, leaving no residual atrial septal tissue at the inferior margin) allows for accurate differentiation between secundum ASDs with inferior extension and inferior SVDs. This differentiation is extremely important

  9. Distribution, level, pharmacology, regulation, and signaling of 5-HT6 receptors in rats and marmosets with special reference to an experimental model of parkinsonism.

    PubMed

    Zhang, Xiaoqun; Andren, Per E; Glennon, Richard A; Svenningsson, Per

    2011-06-15

    Serotonin 5-HT(6) receptors have been implicated in the regulation of cognition, locomotion, and mood, but the elucidation of their functions is complicated by conflicting data using various animal models. Here, a systematic evaluation showed that autoradiographic binding with the selective 5-HT(6) receptor antagonist [(125) I]SB-258585 was similar in marmosets and rats. In both species, [(125) I]SB-258585 binding was enriched in the caudate-putamen. Various recently developed agonists and antagonists toward 5-HT(6) receptors exhibited similarities in their abilities to displace [(125) I]SB-258585 binding in marmosets and rats. The rank order of pEC50 values were as follows: (+)EMDT-CR = EMD386088>MS-245 = 5-HT>EMDT>(-)EMDT-CR; and (+)EMDT-CR = EMD386088>5-HT = MS-245 = EMDT>(-)EMDT-CR, in marmosets and rats, respectively. Unilateral 6-hydroxydopamine lesioning of dopaminergic axons caused a significant decrease of [(125) I]SB-258585 binding in the caudate-putamen of both marmosets and rats. Nonetheless, acute administration of the 5-HT(6) receptor agonist EMDT to unilaterally 6-hydroxydopamine-lesioned rats, caused an induction of egr-1, homer, and enkephalin mRNAs in the dopamine-depleted hemisphere, indicating a supersensitization of 5-HT(6) receptors following dopamine depletion. In conclusion, this study provides evidence for significant similarities in the distribution, level, pharmacology, and regulation of 5-HT(6) receptors between rats and marmosets.

  10. Five-sixth Nephrectomy in Female Common Marmosets(Callithrix jacchus) as a Chronic Renal Failure Model: -A Longitudinal Course of Serum Biochemical, Hematological and Histopathological Changes-.

    PubMed

    Yamaguchi, Itaru; Myojo, Kensuke; Sanada, Hiroko; Takami, Atsuko; Suzuki, Yui; Imaizumi, Minami; Takada, Chie; Kimoto, Naoya; Saeki, Koji; Yamate, Jyoji; Takaba, Katsumi

    2014-10-01

    To assess the relevance and availability of subtotal nephrectomized common marmoset monkeys as a chronic renal failure (CRF) model, we observed for 26 weeks the pathophysiological condition of female marmosets subjected to five-sixth surgical nephrectomy (5/6Nx) by a two-step surgical method. The 5/6Nx marmosets showed a significant increase in serum levels of urea nitrogen, creatinine and cystatin-C immediately after 5/6Nx surgery. These renal disorder parameters subsequently tended to decrease with the passage of time but remained higher than the control levels by the end of the study. Hyperplastic parathyroid glands, a high turnover state of osteodystrophy in the femoral bone with higher serum ALP activity and anemia with hypocellularity of bone marrow were evident. The 5/6Nx marmosets showed a stable CRF condition for a long time and some characteristic disorders similar to those observed in CRF patients. These diagnostic aspects might be a species-specific anatomical and physiological signature, reflecting the nutritional condition. The CRF model using 5/6Nx marmosets might become a useful method of evaluating the unique mechanism of CRF development. PMID:25378803

  11. Abundant Occurrence of Basal Radial Glia in the Subventricular Zone of Embryonic Neocortex of a Lissencephalic Primate, the Common Marmoset Callithrix jacchus

    PubMed Central

    Kelava, Iva; Reillo, Isabel; Murayama, Ayako Y.; Kalinka, Alex T.; Stenzel, Denise; Tomancak, Pavel; Matsuzaki, Fumio; Lebrand, Cécile; Sasaki, Erika; Schwamborn, Jens C.; Okano, Hideyuki; Borrell, Víctor

    2012-01-01

    Subventricular zone (SVZ) progenitors are a hallmark of the developing neocortex. Recent studies described a novel type of SVZ progenitor that retains a basal process at mitosis, sustains expression of radial glial markers, and is capable of self-renewal. These progenitors, referred to here as basal radial glia (bRG), occur at high relative abundance in the SVZ of gyrencephalic primates (human) and nonprimates (ferret) but not lissencephalic rodents (mouse). Here, we analyzed the occurrence of bRG cells in the embryonic neocortex of the common marmoset Callithrix jacchus, a near-lissencephalic primate. bRG cells, expressing Pax6, Sox2 (but not Tbr2), glutamate aspartate transporter, and glial fibrillary acidic protein and retaining a basal process at mitosis, occur at similar relative abundance in the marmoset SVZ as in human and ferret. The proportion of progenitors in M-phase was lower in embryonic marmoset than developing ferret neocortex, raising the possibility of a longer cell cycle. Fitting the gyrification indices of 26 anthropoid species to an evolutionary model suggested that the marmoset evolved from a gyrencephalic ancestor. Our results suggest that a high relative abundance of bRG cells may be necessary, but is not sufficient, for gyrencephaly and that the marmoset's lissencephaly evolved secondarily by changing progenitor parameters other than progenitor type. PMID:22114084

  12. Dense understory and absence of capuchin monkeys (Sapajus xanthosternos) predict higher density of common marmosets (Callithrix jacchus) in the Brazilian Northeast.

    PubMed

    Hilário, Renato R; Ferrari, Stephen F

    2015-04-01

    Understanding the effects of habitat structure and other environmental variables on the density of a species can help define its habitat preferences and key ecological determinants of population parameters. The present study evaluated the effects of fragment size, the presence of a key predator/competitor, the yellow-breasted capuchin (Sapajus xanthosternos), primary productivity, the abundance of bromeliads, and habitat structure on the population density of the common marmoset (Callithrix jacchus). A total of 21 fragments were surveyed within a 350-km long zone of coastal Atlantic Forest representing the southern extreme of the distribution of the species in the Brazilian Northeast. An index of marmoset density was generated for each site based on playback surveys. The relationship between the density of marmosets and a set of parameters was evaluated by multiple regression. A Principal Components Analysis (PCA) condensed the five variables of habitat structure into two principal components, which contained 85% of their combined variation. The model that best explained the density of marmosets (R(2) = 59.1) contained the second PCA component and the presence/absence of capuchins. The analysis indicated that the marmosets prefer forests with denser understory, whether or not they are secondary habitats. The negative effect of the presence of capuchins may be related to predation pressure. The results of this study indicate that multiple-site studies may provide important insights into the habitat preferences of primate species and the factors that affect their population density. PMID:25407393

  13. Developmental expression profiles of axon guidance signaling and the immune system in the marmoset cortex: potential molecular mechanisms of pruning of dendritic spines during primate synapse formation in late infancy and prepuberty (I).

    PubMed

    Sasaki, Tetsuya; Oga, Tomofumi; Nakagaki, Keiko; Sakai, Kazuhisa; Sumida, Kayo; Hoshino, Kohei; Miyawaki, Izuru; Saito, Koichi; Suto, Fumikazu; Ichinohe, Noritaka

    2014-02-14

    The synapse number and the related dendritic spine number in the cerebral cortex of primates shows a rapid increase after birth. Depending on the brain region and species, the number of synapses reaches a peak before adulthood, and pruning takes place after this peak (overshoot-type synaptic formation). Human mental disorders, such as autism and schizophrenia, are hypothesized to be a result of either too weak or excessive pruning after the peak is reached. Thus, it is important to study the molecular mechanisms underlying overshoot-type synaptic formation, particularly the pruning phase. To examine the molecular mechanisms, we used common marmosets (Callithrix jacchus). Microarray analysis of the marmoset cortex was performed in the ventrolateral prefrontal, inferior temporal, and primary visual cortices, where changes in the number of dendritic spines have been observed. The spine number of all the brain regions above showed a peak at 3 months (3 M) after birth and gradually decreased (e.g., at 6 M and in adults). In this study, we focused on genes that showed differential expression between ages of 3 M and 6 M and on the differences whose fold change (FC) was greater than 1.2. The selected genes were subjected to canonical pathway analysis, and in this study, we describe axon guidance signaling, which had high plausibility. The results showed a large number of genes belonging to subsystems within the axon guidance signaling pathway, macrophages/immune system, glutamate system, and others. We divided the data and discussion of these results into 2 papers, and this is the first paper, which deals with the axon guidance signaling and macrophage/immune system. Other systems will be described in the next paper. Many components of subsystems within the axon guidance signaling underwent changes in gene expression from 3 M to 6 M so that the synapse/dendritic spine number would decrease at 6 M. Thus, axon guidance signaling probably contributes to the decrease in

  14. Inferior alveolar and lingual nerve imaging.

    PubMed

    Miloro, Michael; Kolokythas, Antonia

    2011-03-01

    At present, there are no objective testing modalities available for evaluation of iatrogenic injury to the terminal branches of the trigeminal nerve, making such clinical diagnosis and management complicated for the oral and maxillofacial surgeon. Several imaging modalities can assist in the preoperative risk assessment of the trigeminal nerve as related to commonly performed procedures in the vicinity of the nerve, mostly third molar surgery. This article provides a review of all available imaging modalities and their clinical application relative to preoperative injury risk assessment of the inferior alveolar nerve and lingual nerve, and postinjury and postsurgical repair recovery status.

  15. Linking express saccade occurance to stimulus properties and sensorimotor integration in the superior colliculus

    PubMed Central

    Levy, Ron; Munoz, Douglas P.

    2015-01-01

    Express saccades represent the fastest possible eye movements to visual targets with reaction times that approach minimum sensory-motor conduction delays. Previous work in monkeys has identified two specific neural signals in the superior colliculus (SC: a midbrain sensorimotor integration structure involved in gaze control) that are required to execute express saccades: 1) previsual activity consisting of a low-frequency increase in action potentials in sensory-motor neurons immediately before the arrival of a visual response; and 2) a transient visual-sensory response consisting of a high-frequency burst of action potentials in visually responsive neurons resulting from the appearance of a visual target stimulus. To better understand how these two neural signals interact to produce express saccades, we manipulated the arrival time and magnitude of visual responses in the SC by altering target luminance and we examined the corresponding influences on SC activity and express saccade generation. We recorded from saccade neurons with visual-, motor-, and previsual-related activity in the SC of monkeys performing the gap saccade task while target luminance was systematically varied between 0.001 and 42.5 cd/m2 against a black background (∼0.0001 cd/m2). Our results demonstrated that 1) express saccade latencies were linked directly to the arrival time in the SC of visual responses produced by abruptly appearing visual stimuli; 2) express saccades were generated toward both dim and bright targets whenever sufficient previsual activity was present; and 3) target luminance altered the likelihood of producing an express saccade. When an express saccade was generated, visuomotor neurons increased their activity immediately before the arrival of the visual response in the SC and saccade initiation. Furthermore, the visual and motor responses of visuomotor neurons merged into a single burst of action potentials, while the visual response of visual-only neurons was

  16. Linking express saccade occurance to stimulus properties and sensorimotor integration in the superior colliculus.

    PubMed

    Marino, Robert A; Levy, Ron; Munoz, Douglas P

    2015-08-01

    Express saccades represent the fastest possible eye movements to visual targets with reaction times that approach minimum sensory-motor conduction delays. Previous work in monkeys has identified two specific neural signals in the superior colliculus (SC: a midbrain sensorimotor integration structure involved in gaze control) that are required to execute express saccades: 1) previsual activity consisting of a low-frequency increase in action potentials in sensory-motor neurons immediately before the arrival of a visual response; and 2) a transient visual-sensory response consisting of a high-frequency burst of action potentials in visually responsive neurons resulting from the appearance of a visual target stimulus. To better understand how these two neural signals interact to produce express saccades, we manipulated the arrival time and magnitude of visual responses in the SC by altering target luminance and we examined the corresponding influences on SC activity and express saccade generation. We recorded from saccade neurons with visual-, motor-, and previsual-related activity in the SC of monkeys performing the gap saccade task while target luminance was systematically varied between 0.001 and 42.5 cd/m(2) against a black background (∼0.0001 cd/m(2)). Our results demonstrated that 1) express saccade latencies were linked directly to the arrival time in the SC of visual responses produced by abruptly appearing visual stimuli; 2) express saccades were generated toward both dim and bright targets whenever sufficient previsual activity was present; and 3) target luminance altered the likelihood of producing an express saccade. When an express saccade was generated, visuomotor neurons increased their activity immediately before the arrival of the visual response in the SC and saccade initiation. Furthermore, the visual and motor responses of visuomotor neurons merged into a single burst of action potentials, while the visual response of visual-only neurons was

  17. Comparison of visual receptive field properties of the superior colliculus and primary visual cortex in rats.

    PubMed

    Li, Xiaoyuan; Sun, Chaokui; Shi, Li

    2015-08-01

    The rat visual system comprises cortical and subcortical pathways. The receptive field properties of cells in the visual cortex have been extensively studied; however, the fundamental roles of the two circuits in visual information processing are not well understood. To address this question, we have applied quantitative methods to compare and characterize the spatiotemporal receptive field (RF) properties of neurons in primary visual cortex (V1) cells and superficial layers of the superior colliculus (SC) in rats by means of extracellular recordings. An analysis of visual stimulus processing revealed distinct functional characteristics of the two visual circuits. RF diameters of SC neurons were significantly larger than those of V1 cells. Most cells in both regions had high orientation selectivity, but the mean orientation bandwidth of the SC was broader than that of V1 cells (101.5° vs. 60.2°). The mean optimal spatial frequency (SF) of SC cells was lower but had a broader bandwidth than that of V1 cells (0.03 vs. 0.068 cpd). The majority of SC and V1 cells (70% and 68%, respectively) had RFs with band-pass temporal frequency (TF) tuning profiles and similar optimal TFs. However, temporal band-pass profiles of the SC showed narrower mean temporal bandwidths than those of V1 cells (1.42 vs. 2.36 octaves). The majority of neurons in visual cortical and subcortical structures were activated in response to high-contrast, drifting gratings in the preferred orientation. The percentage of V1 neurons with a low-contrast threshold was larger than the proportion of SC neurons (45.6% vs. 30%), indicating that the former adapt better to contrast. The substantial overlap in latency distributions between SC and V1 areas suggests that the two visual systems process and analyze visual signals in parallel. However, the two areas use different neural encoding mechanisms based on different latency distribution trends. These results indicate that SC cells have poor spatial acuity

  18. Development of a modified artificial insemination technique combining penile vibration stimulation and the swim-up method in the common marmoset.

    PubMed

    Takabayashi, Shuji; Suzuki, Yuiko; Katoh, Hideki

    2015-05-01

    The common marmoset, Callithrix jacchus, is used as a New World monkey species in biomedical studies because of its small body size and good reproduction in captivity. A modified artificial insemination technique was developed in this species to encourage breeding of lines carrying interesting genes and traits. Fresh semen was collected by penile vibratory stimulation. Medium containing highly motile sperm was inseminated into the uterus using a catheter. Seven females were inseminated using freshly prepared sperm from different males every day for 3 days including the expected ovulation day. As a result, four females conceived, and three females delivered six offspring in total (two singletons and one quadruplet). The paternity of the newborns was determined using microsatellite markers to accurately pinpoint the timing of insemination and ovulation. It is expected that our artificial insemination protocol can be effectively used to establish marmoset lines and genetically manage marmoset colonies.

  19. Development of a GB virus B marmoset model and its validation with a novel series of hepatitis C virus NS3 protease inhibitors.

    PubMed

    Bright, Helen; Carroll, Anthony R; Watts, Paul A; Fenton, Robert J

    2004-02-01

    GB virus B (GBV-B), a flavivirus closely related to HCV, has previously been shown to infect and replicate to high titers in tamarins (Saguinus sp.). This study describes the use of GBV-B infection and replication in the common marmoset (Callithrix jacchus) for the successful development and validation of a surrogate animal model for hepatitis C virus (HCV). Infection of marmosets with GBV-B produced a viremia that peaked at 10(8) to 10(9) genome copies/ml for a period of 40 to 60 days followed by viral