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Sample records for neural plasticity habituation

  1. A Realistic Neural Mass Model of the Cortex with Laminar-Specific Connections and Synaptic Plasticity – Evaluation with Auditory Habituation

    PubMed Central

    Wang, Peng; Knösche, Thomas R.

    2013-01-01

    In this work we propose a biologically realistic local cortical circuit model (LCCM), based on neural masses, that incorporates important aspects of the functional organization of the brain that have not been covered by previous models: (1) activity dependent plasticity of excitatory synaptic couplings via depleting and recycling of neurotransmitters and (2) realistic inter-laminar dynamics via laminar-specific distribution of and connections between neural populations. The potential of the LCCM was demonstrated by accounting for the process of auditory habituation. The model parameters were specified using Bayesian inference. It was found that: (1) besides the major serial excitatory information pathway (layer 4 to layer 2/3 to layer 5/6), there exists a parallel “short-cut” pathway (layer 4 to layer 5/6), (2) the excitatory signal flow from the pyramidal cells to the inhibitory interneurons seems to be more intra-laminar while, in contrast, the inhibitory signal flow from inhibitory interneurons to the pyramidal cells seems to be both intra- and inter-laminar, and (3) the habituation rates of the connections are unsymmetrical: forward connections (from layer 4 to layer 2/3) are more strongly habituated than backward connections (from Layer 5/6 to layer 4). Our evaluation demonstrates that the novel features of the LCCM are of crucial importance for mechanistic explanations of brain function. The incorporation of these features into a mass model makes them applicable to modeling based on macroscopic data (like EEG or MEG), which are usually available in human experiments. Our LCCM is therefore a valuable building block for future realistic models of human cognitive function. PMID:24205009

  2. Habituation in non-neural organisms: evidence from slime moulds.

    PubMed

    Boisseau, Romain P; Vogel, David; Dussutour, Audrey

    2016-04-27

    Learning, defined as a change in behaviour evoked by experience, has hitherto been investigated almost exclusively in multicellular neural organisms. Evidence for learning in non-neural multicellular organisms is scant, and only a few unequivocal reports of learning have been described in single-celled organisms. Here we demonstrate habituation, an unmistakable form of learning, in the non-neural organism Physarum polycephalum In our experiment, using chemotaxis as the behavioural output and quinine or caffeine as the stimulus, we showed that P. polycephalum learnt to ignore quinine or caffeine when the stimuli were repeated, but responded again when the stimulus was withheld for a certain time. Our results meet the principle criteria that have been used to demonstrate habituation: responsiveness decline and spontaneous recovery. To distinguish habituation from sensory adaptation or motor fatigue, we also show stimulus specificity. Our results point to the diversity of organisms lacking neurons, which likely display a hitherto unrecognized capacity for learning, and suggest that slime moulds may be an ideal model system in which to investigate fundamental mechanisms underlying learning processes. Besides, documenting learning in non-neural organisms such as slime moulds is centrally important to a comprehensive, phylogenetic understanding of when and where in the tree of life the earliest manifestations of learning evolved.

  3. Habituation in non-neural organisms: evidence from slime moulds.

    PubMed

    Boisseau, Romain P; Vogel, David; Dussutour, Audrey

    2016-04-27

    Learning, defined as a change in behaviour evoked by experience, has hitherto been investigated almost exclusively in multicellular neural organisms. Evidence for learning in non-neural multicellular organisms is scant, and only a few unequivocal reports of learning have been described in single-celled organisms. Here we demonstrate habituation, an unmistakable form of learning, in the non-neural organism Physarum polycephalum In our experiment, using chemotaxis as the behavioural output and quinine or caffeine as the stimulus, we showed that P. polycephalum learnt to ignore quinine or caffeine when the stimuli were repeated, but responded again when the stimulus was withheld for a certain time. Our results meet the principle criteria that have been used to demonstrate habituation: responsiveness decline and spontaneous recovery. To distinguish habituation from sensory adaptation or motor fatigue, we also show stimulus specificity. Our results point to the diversity of organisms lacking neurons, which likely display a hitherto unrecognized capacity for learning, and suggest that slime moulds may be an ideal model system in which to investigate fundamental mechanisms underlying learning processes. Besides, documenting learning in non-neural organisms such as slime moulds is centrally important to a comprehensive, phylogenetic understanding of when and where in the tree of life the earliest manifestations of learning evolved. PMID:27122563

  4. Habituation and dishabituation mediated by the peripheral and central neural circuits of the siphon of Aplysia.

    PubMed

    Lukowiak, K; Jacklet, J

    1975-03-01

    The siphon withdrawal response evoked by a weak tactile (water drop) or light stimulus is mediated primarily by neurons in the siphon. Central neurons (abdominal ganglion) contribute very little since the response amplitude and latency are not changed following removal of the abdominal ganglion. Similarly, habituation and dishabituation of this withdrawal response are not different after removal of the abdominal ganglion, indicating that the peripheral neural circuit in the isolated siphon can mediate habituation itself, and thus has many of the properties attributed to central neurons. Response evoked by electrical stimulation of the siphon nerve habituate, depending upon the stimulus intensity and interval. These habituated responses may be dishabituated by tactile or light stimulation of the siphon. These results show that each neural system, peripheral and central, has an excitatory modulatory influence on the other. Normally adaptive siphon responses must be shaped by the integrated activity of both of these neural systems.

  5. Gustatory Habituation in "Drosophila" Relies on "Rutabaga" (Adenylate Cyclase)-Dependent Plasticity of GABAergic Inhibitory Neurons

    ERIC Educational Resources Information Center

    Paranjpe, Pushkar; Rodrigues, Veronica; VijayRaghavan, K.; Ramaswami, Mani

    2012-01-01

    In some situations, animals seem to ignore stimuli which in other contexts elicit a robust response. This attenuation in behavior, which enables animals to ignore a familiar, unreinforced stimulus, is called habituation. Despite the ubiquity of this phenomenon, it is generally poorly understood in terms of the underlying neural circuitry. Hungry…

  6. Individual variation in behavioural plasticity: direct and indirect effects of boldness, exploration and sociability on habituation to predators in lizards

    PubMed Central

    Rodríguez-Prieto, Iñaki; Martín, José; Fernández-Juricic, Esteban

    2011-01-01

    Little is known about the factors causing variation in behavioural plasticity and the interplay between personality and plasticity. Habituation to predators is a special case of behavioural plasticity. We investigated the direct and indirect effects of boldness, exploration and sociability traits on the habituation ability of Iberian wall lizards, considering exposure and sex effects. Individual boldness was consistent across several non-habituation contexts, but it did not significantly affect habituation. Exploration had a strong direct effect on habituation, with more exploratory individuals being able to habituate faster than less exploratory ones, probably because of their ability to assess risk better. Individual variation in habituation was also affected by sociability, but this was an indirect effect mediated by exposure to the predator. Less social individuals avoided refuges with conspecific cues, increasing exposure to the predator and eventually habituation. Finally, the direct effects of sex (females habituated faster than males) were opposite to its indirect effects through exposure. We conclude that risk assessment, instead of the proactivity–reactivity gradient usually considered in the literature, can affect behavioural plasticity through complex interactions between direct and indirect effects, including exploratory behaviour, degree of exposure to the predator and sex, which represent novel mechanisms generating inter-individual variation in plasticity. PMID:20685703

  7. Neural plasticity: changes with age.

    PubMed

    Nieto-Sampedro, M; Nieto-Díaz, M

    2005-01-01

    Changes in the number, type and function of nervous system connections, in the morphology and function of glia and in neuron-glia interactions, are at the basis of vertebrate adjustment to changing environmental and physiological conditions. Collected under "neural plasticity", these age-dependent changes underlie adaptations apparently as different as the physiological response to dehydration or learning, and its electrophysiological and morphological correlates.

  8. Genetic influences on neural plasticity.

    PubMed

    Pearson-Fuhrhop, Kristin M; Cramer, Steven C

    2010-12-01

    Neural plasticity refers to the capability of the brain to alter function or structure in response to a range of events and is a crucial component of both functional recovery after injury and skill learning in healthy individuals. A number of factors influence neural plasticity and recovery of function after brain injury. The current review considers the impact of genetic factors. Polymorphisms in the human genes coding for brain-derived neurotrophic factor and apolipoprotein E have been studied in the context of plasticity and stroke recovery and are discussed here in detail. Several processes involved in plasticity and stroke recovery, such as depression or pharmacotherapy effects, are modulated by other genetic polymorphisms and are also discussed. Finally, new genetic polymorphisms that have not been studied in the context of stroke are proposed as new directions for study. A better understanding of genetic influences on recovery and response to therapy might allow improved treatment after a number of forms of central nervous system injury.

  9. Neural plasticity: the biological substrate for neurorehabilitation.

    PubMed

    Warraich, Zuha; Kleim, Jeffrey A

    2010-12-01

    Decades of basic science have clearly demonstrated the capacity of the central nervous system (CNS) to structurally and functionally adapt in response to experience. The field of neurorehabilitation has begun to use this body of work to develop neurobiologically informed therapies that harness the key behavioral and neural signals that drive neural plasticity. The present review describes how neural plasticity supports both learning in the intact CNS and functional improvement in the damaged or diseased CNS. A pragmatic, interdisciplinary definition of neural plasticity is presented that may be used by both clinical and basic scientists studying neurorehabilitation. Furthermore, a description of how neural plasticity may act to drive different neural strategies underlying functional improvement after CNS injury or disease is provided. The understanding of the relationship between these different neural strategies, mechanisms of neural plasticity, and changes in behavior may facilitate the development of novel, more effective rehabilitation interventions. PMID:21172683

  10. Neural Correlates of Empathy with Pain Show Habituation Effects. An fMRI Study

    PubMed Central

    Preis, Mira A.; Kröner-Herwig, Birgit; Schmidt-Samoa, Carsten; Dechent, Peter; Barke, Antonia

    2015-01-01

    Background Neuroimaging studies have demonstrated that the actual experience of pain and the perception of another person in pain share common neural substrates, including the bilateral anterior insular cortex and the anterior midcingulate cortex. As many fMRI studies include the exposure of participants to repeated, similar stimuli, we examined whether empathic neural responses were affected by habituation and whether the participants' prior pain experience influenced these habituation effects. Method In 128 trials (four runs), 62 participants (31 women, 23.0 ± 4.2 years) were shown pictures of hands exposed to painful pressure (pain pictures) and unexposed (neutral pictures). After each trial, the participants rated the pain of the model. Prior to the experiment, participants were either exposed to the same pain stimulus (pain exposure group) or not (touch exposure group). In order to assess possible habituation effects, linear changes in the strength of the BOLD response to the pain pictures (relative to the neutral pictures) and in the ratings of the model’s pain were evaluated across the four runs. Results Although the ratings of the model’s pain remained constant over time, we found neural habituation in the bilateral anterior/midinsular cortex, the posterior midcingulate extending to dorsal posterior cingulate cortex, the supplementary motor area, the cerebellum, the right inferior parietal lobule, and the left superior frontal gyrus, stretching to the pregenual anterior cingulate cortex. The participant’s prior pain experience did neither affect their ratings of the model’s pain nor their maintenance of BOLD activity in areas associated with empathy. Interestingly, participants with high trait personal distress and fantasy tended to show less habituation in the anterior insula. Conclusion Neural structures showed a decrease of the BOLD signal, indicating habituation over the course of 45 minutes. This can be interpreted as a neuronal mechanism

  11. Olfactory habituation in Drosophila-odor encoding and its plasticity in the antennal lobe.

    PubMed

    Twick, Isabell; Lee, John Anthony; Ramaswami, Mani

    2014-01-01

    A ubiquitous feature of an animal's response to an odorant is that it declines when the odorant is frequently or continuously encountered. This decline in olfactory response, termed olfactory habituation, can have temporally or mechanistically different forms. The neural circuitry of the fruit fly Drosophila melanogaster's olfactory system is well defined in terms of component cells, which are readily accessible to functional studies and genetic manipulation. This makes it a particularly useful preparation for the investigation of olfactory habituation. In addition, the insect olfactory system shares many architectural and functional similarities with mammalian olfactory systems, suggesting that olfactory mechanisms in insects may be broadly relevant. In this chapter, we discuss the likely mechanisms of olfactory habituation in context of the participating cell types, their connectivity, and their roles in sensory processing. We overview the structure and function of key cell types, the mechanisms that stimulate them, and how they transduce and process odor signals. We then consider how each stage of olfactory processing could potentially contribute to behavioral habituation. After this, we overview a variety of recent mechanistic studies that point to an important role for potentiation of inhibitory synapses in the primary olfactory processing center, the antennal lobe, in driving the reduced response to familiar odorants. Following the discussion of mechanisms for short- and long-term olfactory habituation, we end by considering how these mechanisms may be regulated by neuromodulators, which likely play key roles in the induction, gating, or suppression of habituated behavior, and speculate on the relevance of these processes for other forms of learning and memory.

  12. Visual recognition memory, manifest as long-term habituation, requires synaptic plasticity in V1

    PubMed Central

    Cooke, Sam F.; Komorowski, Robert W.; Kaplan, Eitan S.; Gavornik, Jeffrey P.; Bear, Mark F.

    2015-01-01

    Familiarity with stimuli that bring neither reward nor punishment, manifested through behavioural habituation, enables organisms to detect novelty and devote cognition to important elements of the environment. Here we describe in mice a form of long-term behavioural habituation to visual grating stimuli that is selective for stimulus orientation. Orientation-selective habituation (OSH) can be observed both in exploratory behaviour in an open arena, and in a stereotyped motor response to visual stimuli in head-restrained mice. We show that the latter behavioural response, termed a vidget, requires V1. Parallel electrophysiological recordings in V1 reveal that plasticity, in the form of stimulus-selective response potentiation (SRP), occurs in layer 4 of V1 as OSH develops. Local manipulations of V1 that prevent and reverse electrophysiological modifications likewise prevent and reverse memory demonstrated behaviourally. These findings suggest that a form of long-term visual recognition memory is stored via synaptic plasticity in primary sensory cortex. PMID:25599221

  13. Modeling habituation in rat EEG-evoked responses via a neural mass model with feedback

    PubMed Central

    Tadmor, Gilead; Diamond, Solomon G.; Miller, Eric; Franceschini, Maria Angela; Brooks, Dana H.

    2012-01-01

    Habituation is a generic property of the neural response to repeated stimuli. Its strength often increases as inter-stimuli relaxation periods decrease. We propose a simple, broadly applicable control structure that enables a neural mass model of the evoked EEG response to exhibit habituated behavior. A key motivation for this investigation is the ongoing effort to develop model-based reconstruction of multimodal functional neuroimaging data. The control structure proposed here is illustrated and validated in the context of a biophysical neural mass model, developed by Riera et al. (Hum Brain Mapp 27(11):896–914, 2006; 28(4):335–354, 2007), and of simplifications thereof, using data from rat EEG response to medial nerve stimuli presented at frequencies from 1 to 8 Hz. Performance was tested by predictions of both the response to the next stimulus based on the current one, and also of continued stimuli trains over 4-s time intervals based on the first stimulus in the interval, with similar success statistics. These tests demonstrate the ability of simple generative models to capture key features of the evoked response, including habituation. PMID:22282292

  14. Neural Plasticity in Speech Acquisition and Learning

    ERIC Educational Resources Information Center

    Zhang, Yang; Wang, Yue

    2007-01-01

    Neural plasticity in speech acquisition and learning is concerned with the timeline trajectory and the mechanisms of experience-driven changes in the neural circuits that support or disrupt linguistic function. In this selective review, we discuss the role of phonetic learning in language acquisition, the "critical period" of learning, the agents…

  15. Neural network simulation of habituation and dishabituation in infant speech perception

    NASA Astrophysics Data System (ADS)

    Gauthier, Bruno; Shi, Rushen; Proulx, Robert

    2001-05-01

    The habituation techniques used in infant speech perception studies are based on the fact that infants show renewed interest towards novel stimuli. Recent work has shown the possibility of using artificial neural networks to model habituation and dishabituation (e.g., Schafer and Mareschal, 2001). In our study we examine weather the self-organizing-feature-maps (SOM) (Kohonen, 1989) are appropriate for modeling short-term habituation to a repeated speech stimulus. We found that although SOMs are particularly useful for simulating categorization, they can be modified to model habituation and dishabituation, so that they can be applied to direct comparisons with behavioral data on infants' speech discrimination abilities. In particular, we modified the SOMs to include additional parameters that control the relation of input similarity, lateral inhibition, and local and lateral activation between neurons. Preliminary results suggest that these parameters are sufficient for the network to simulate the loss of sensitivity of the auditory system due to the presentation of multiple tokens of a speech stimulus, as well as to model the recovery of sensitivity to a novel stimulus. The implications of this approach to infant speech perception research will be considered.

  16. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli.

    PubMed

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

    Psychostimulants have many effects on visual function, from adverse following acute and prenatal exposure to therapeutic on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF) and dark (DF) flashes elicited similar responses in the optic tectum neuropil (TOn), while the dorsal telencephalon (dTe) responded only to LF. Acute cocaine (0.5 μM) reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation (RSP) led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure (PCE) prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals), responses to LF are more complex, involving dTe (homologous to the cerebral cortex), and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that PCE modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by PCE may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological interventions.

  17. Neural Plasticity: For Good and Bad

    NASA Astrophysics Data System (ADS)

    Møller, A. R.

    The brain's ability to change its organization and function is necessary for normal development of the nervous system and it makes it possible to adapt to changing demands but it can also cause disorders when going awry. This property, known as neural plasticity, is only evident when induced, very much like genes. Plastic changes may be programmed and providing a ``midcourse correction" during childhood development. If that is not executed in the normal way severe developmental disorders such as autism may results. Normal development of functions and anatomical organization of the brain and the spinal cord depend on appropriate sensory stimulation and motor activations. So-called enriched sensory environments have been shown to be beneficial for cognitive development and enriched acoustic environment may even slow the progression of age-related hearing loss. It is possible that the beneficial effect of physical exercise is achieved through activation of neural plasticity. The beneficial effect of training after trauma to the brain or spinal cord is mainly achieved through shifting functions from damaged brain area to other parts of the central nervous system and adapting these parts to take over the functions that are lost. This is accomplished through activation of neural plasticity. Plastic changes can also be harmful and cause symptoms and signs of disorders such as some forms of chronic pain (central neuropathic pain) and severe tinnitus. We will call such disorders ``plasticity disorders".

  18. Neural responsivity during soft drink intake, anticipation, and advertisement exposure in habitually consuming youth

    PubMed Central

    Burger, Kyle S.; Stice, Eric

    2014-01-01

    OBJECTIVE Although soft drinks are heavily advertised, widely consumed, and have been associated with obesity, little is understood regarding neural responsivity to soft drink intake, anticipated intake, and advertisements. METHODS Functional MRI was used to assess examine neural response to carbonated soft drink intake, anticipated intake and advertisement exposure as well as milkshake intake in 27 adolescents that varied on soft drink consumer status. RESULTS Intake and anticipated intake of carbonated Coke® activated regions implicated in gustatory, oral somatosensory, and reward processing, yet high-fat/sugar milkshake intake elicited greater activation in these regions versus Coke intake. Advertisements highlighting the Coke product vs. non-food control advertisements, but not the Coke logo, activated gustatory and visual brain regions. Habitual Coke consumers vs. non-consumers showed greater posterior cingulate responsivity to Coke logo ads, suggesting that the logo is a conditioned cue. Coke consumers exhibited less ventrolateral prefrontal cortex responsivity during anticipated Coke intake relative to non-consumers. CONCLUSIONS Results indicate that soft drinks activate reward and gustatory regions, but are less potent in activating these regions than high-fat/sugar beverages, and imply that habitual soft drink intake promotes hyper-responsivity of regions encoding salience/attention toward brand specific cues and hypo-responsivity of inhibitory regions while anticipating intake. PMID:23836764

  19. Imbalance in habitual versus goal directed neural systems during symptom provocation in obsessive-compulsive disorder.

    PubMed

    Banca, Paula; Voon, Valerie; Vestergaard, Martin D; Philipiak, Gregor; Almeida, Inês; Pocinho, Fernando; Relvas, João; Castelo-Branco, Miguel

    2015-03-01

    Intrusive thoughts and compulsive urges to perform stereotyped behaviours are typical symptoms of obsessive-compulsive disorder. Emerging evidence suggests a cognitive bias towards habit formation at the expense of goal-directed performance in obsessive-compulsive disorder. In this study, we test this hypothesis using a novel individualized ecologically valid symptom provocation design: a live provocation functional magnetic resonance imaging paradigm with synchronous video-recording of behavioural avoidance responses. By pairing symptom provocation with online avoidance responses on a trial-by-trial basis, we sought to investigate the neural mechanisms leading to the compulsive avoidance response. In keeping with the model of habit formation in obsessive-compulsive disorder, we hypothesized that this disorder would be associated with lower activity in regions implicated in goal-directed behaviours and higher activity in regions implicated in habitual behaviours. Fifteen patients with obsessive-compulsive disorder and 15 healthy control volunteers participated in this functional magnetic resonance imaging study. Online stimuli were individually tailored to achieve effective symptom provocation at neutral, intermediate and strong intensity levels. During the symptom provocation block, the participant could choose to reject or terminate the provoking stimuli resulting in cessation of the symptom provocation. We thus separately analysed the neural correlates of symptom provocation, the urge to avoid, rejection and relief. Strongly symptom-provoking conditions evoked a dichotomous pattern of deactivation/activation in patients, which was not observed either in control conditions or in healthy subjects: a deactivation of caudate-prefrontal circuits accompanied by hyperactivation of subthalamic nucleus/putaminal regions. This finding suggests a dissociation between regions engaged in goal-directed and habitual behaviours. The putaminal hyperactivity during patients

  20. Imbalance in habitual versus goal directed neural systems during symptom provocation in obsessive-compulsive disorder

    PubMed Central

    Banca, Paula; Voon, Valerie; Vestergaard, Martin D.; Philipiak, Gregor; Almeida, Inês; Pocinho, Fernando; Relvas, João

    2015-01-01

    Intrusive thoughts and compulsive urges to perform stereotyped behaviours are typical symptoms of obsessive-compulsive disorder. Emerging evidence suggests a cognitive bias towards habit formation at the expense of goal-directed performance in obsessive-compulsive disorder. In this study, we test this hypothesis using a novel individualized ecologically valid symptom provocation design: a live provocation functional magnetic resonance imaging paradigm with synchronous video-recording of behavioural avoidance responses. By pairing symptom provocation with online avoidance responses on a trial-by-trial basis, we sought to investigate the neural mechanisms leading to the compulsive avoidance response. In keeping with the model of habit formation in obsessive-compulsive disorder, we hypothesized that this disorder would be associated with lower activity in regions implicated in goal-directed behaviours and higher activity in regions implicated in habitual behaviours. Fifteen patients with obsessive-compulsive disorder and 15 healthy control volunteers participated in this functional magnetic resonance imaging study. Online stimuli were individually tailored to achieve effective symptom provocation at neutral, intermediate and strong intensity levels. During the symptom provocation block, the participant could choose to reject or terminate the provoking stimuli resulting in cessation of the symptom provocation. We thus separately analysed the neural correlates of symptom provocation, the urge to avoid, rejection and relief. Strongly symptom-provoking conditions evoked a dichotomous pattern of deactivation/activation in patients, which was not observed either in control conditions or in healthy subjects: a deactivation of caudate-prefrontal circuits accompanied by hyperactivation of subthalamic nucleus/putaminal regions. This finding suggests a dissociation between regions engaged in goal-directed and habitual behaviours. The putaminal hyperactivity during patients

  1. Neural plasticity in adults with amblyopia.

    PubMed Central

    Levi, D M; Polat, U

    1996-01-01

    Amblyopia is a neuronal abnormality of vision that is often considered irreversible in adults. We found strong and significant improvement of Vernier acuity in human adults with naturally occurring amblyopia following practice. Learning was strongest at the trained orientation and did not transfer to an untrained task (detection), but it did transfer partially to the untrained eye (primarily at the trained orientation). We conclude that this perceptual learning reflects alterations in early neural processes that are localized beyond the site of convergence of the two eyes. Our results suggest a significant degree of plasticity in the visual system of adults with amblyopia. PMID:8692904

  2. Neural mechanisms of behavioral plasticity: metamorphosis and learning in Manduca sexta.

    PubMed

    Weeks, J C; Jacobs, G A; Pierce, J T; Sandstrom, D J; Streichert, L C; Trimmer, B A; Wiel, D E; Wood, E R

    1997-01-01

    This review summarizes our current understanding of the neural circuit underlying the larval proleg withdrawal reflex (PWR) of Manduca sexta and describes how PWR function changes in two contexts: metamorphosis and learning. The first form of PWR plasticity occurs during the larval-pupal transformation, when the reflex is lost. One mechanism that contributes to this loss is the weakening of monosynaptic excitatory connection from proleg sensory neurons to proleg retractor motor neurons. This change is associated with the hormonally-mediated regression of proleg motor neuron dendrites, which may break synaptic contacts between the sensory and motor neurons. After pupation, some of the proleg motor neurons die in a segment-specific pattern that persists even after individual motor neurons are isolated from the nervous system and exposed to hormones in vitro. The second form of PWR plasticity involves short-term, activity-dependent changes in neural function during the larval stage. The nicotinic cholinergic connections from proleg sensory neurons to motor neurons exhibit several forms of plasticity including facilitation, depression, post-tetanic potentiation and two types of muscarinic modulation. Larval PWR behavior exhibits two simple forms of learning-habituation and dishabituation-which involve alterations in the central PWR circuit. These studies of a simple circuit illustrate neural mechanisms by which behaviors undergo both short- and long-term modifications.

  3. Neural Plasticity and Neurorehabilitation: Teaching the New Brain Old Tricks

    ERIC Educational Resources Information Center

    Kleim, Jeffrey A.

    2011-01-01

    Following brain injury or disease there are widespread biochemical, anatomical and physiological changes that result in what might be considered a new, very different brain. This adapted brain is forced to reacquire behaviors lost as a result of the injury or disease and relies on neural plasticity within the residual neural circuits. The same…

  4. Short-term synaptic plasticity and heterogeneity in neural systems

    NASA Astrophysics Data System (ADS)

    Mejias, J. F.; Kappen, H. J.; Longtin, A.; Torres, J. J.

    2013-01-01

    We review some recent results on neural dynamics and information processing which arise when considering several biophysical factors of interest, in particular, short-term synaptic plasticity and neural heterogeneity. The inclusion of short-term synaptic plasticity leads to enhanced long-term memory capacities, a higher robustness of memory to noise, and irregularity in the duration of the so-called up cortical states. On the other hand, considering some level of neural heterogeneity in neuron models allows neural systems to optimize information transmission in rate coding and temporal coding, two strategies commonly used by neurons to codify information in many brain areas. In all these studies, analytical approximations can be made to explain the underlying dynamics of these neural systems.

  5. Shaping the learning curve: epigenetic dynamics in neural plasticity

    PubMed Central

    Bronfman, Zohar Z.; Ginsburg, Simona; Jablonka, Eva

    2014-01-01

    A key characteristic of learning and neural plasticity is state-dependent acquisition dynamics reflected by the non-linear learning curve that links increase in learning with practice. Here we propose that the manner by which epigenetic states of individual cells change during learning contributes to the shape of the neural and behavioral learning curve. We base our suggestion on recent studies showing that epigenetic mechanisms such as DNA methylation, histone acetylation, and RNA-mediated gene regulation are intimately involved in the establishment and maintenance of long-term neural plasticity, reflecting specific learning-histories and influencing future learning. Our model, which is the first to suggest a dynamic molecular account of the shape of the learning curve, leads to several testable predictions regarding the link between epigenetic dynamics at the promoter, gene-network, and neural-network levels. This perspective opens up new avenues for therapeutic interventions in neurological pathologies. PMID:25071483

  6. [The pathological neural plasticity and its application in acupuncture research].

    PubMed

    Zhao, Hui-ying; Mu, Ping; Dong, Yan

    2008-02-01

    The central nervous system (CNS) is involved in a variety of disease conditions. Some seeming peripheral diseases, like chronic pain and disorders in major organs, indeed have clear pathological basis in the CNS. On the other hand, some clinically-beneficial peripheral stimulation, such as acupuncture and massage, exerts significant influence on central neurons. This review attempts to summary recent findings in neuroscience about how pathological insults long-term plastic changes within neural circuits, leading to maladaptive behaviors. This neuroplasticity-based theory not only conceptualizes a cellular mechanism for a plethora of neuropathophysiology but also provides clinical strategies for treating neural diseases. Drug addiction is a chronic brain disease, defined as compulsive drug-seeking, drug-craving, and drug-taking behaviors. Extensive experimental evidence suggests that following exposure to drugs of abuse, neurons within the mesolimbic dopamine system undergo a series of plastic changes that may lead to compulsive emotional and motivational states. It is believed that the first step to unlock the secret of drug addiction is to identify, evaluate, and conceptualize drug-induced neural plasticity. Synaptic plasticity is one form of neuroplasticity that has been best characterized. Using addiction-related synaptic plasticity as a working model, this review attempts to depict the general concept and experimental approach in studying the pathophysiological neural basis of acupuncture.

  7. Perineuronal net, CSPG receptor and their regulation of neural plasticity.

    PubMed

    Miao, Qing-Long; Ye, Qian; Zhang, Xiao-Hui

    2014-08-25

    Perineuronal nets (PNNs) are reticular structures resulting from the aggregation of extracellular matrix (ECM) molecules around the cell body and proximal neurite of specific population of neurons in the central nervous system (CNS). Since the first description of PNNs by Camillo Golgi in 1883, the molecular composition, developmental formation and potential functions of these specialized extracellular matrix structures have only been intensively studied over the last few decades. The main components of PNNs are hyaluronan (HA), chondroitin sulfate proteoglycans (CSPGs) of the lectican family, link proteins and tenascin-R. PNNs appear late in neural development, inversely correlating with the level of neural plasticity. PNNs have long been hypothesized to play a role in stabilizing the extracellular milieu, which secures the characteristic features of enveloped neurons and protects them from the influence of malicious agents. Aberrant PNN signaling can lead to CNS dysfunctions like epilepsy, stroke and Alzheimer's disease. On the other hand, PNNs create a barrier which constrains the neural plasticity and counteracts the regeneration after nerve injury. Digestion of PNNs with chondroitinase ABC accelerates functional recovery from the spinal cord injury and restores activity-dependent mechanisms for modifying neuronal connections in the adult animals, indicating that PNN is an important regulator of neural plasticity. Here, we review recent progress in the studies on the formation of PNNs during early development and the identification of CSPG receptor - an essential molecular component of PNN signaling, along with a discussion on their unique regulatory roles in neural plasticity.

  8. Computational modeling of neural plasticity for self-organization of neural networks.

    PubMed

    Chrol-Cannon, Joseph; Jin, Yaochu

    2014-11-01

    Self-organization in biological nervous systems during the lifetime is known to largely occur through a process of plasticity that is dependent upon the spike-timing activity in connected neurons. In the field of computational neuroscience, much effort has been dedicated to building up computational models of neural plasticity to replicate experimental data. Most recently, increasing attention has been paid to understanding the role of neural plasticity in functional and structural neural self-organization, as well as its influence on the learning performance of neural networks for accomplishing machine learning tasks such as classification and regression. Although many ideas and hypothesis have been suggested, the relationship between the structure, dynamics and learning performance of neural networks remains elusive. The purpose of this article is to review the most important computational models for neural plasticity and discuss various ideas about neural plasticity's role. Finally, we suggest a few promising research directions, in particular those along the line that combines findings in computational neuroscience and systems biology, and their synergetic roles in understanding learning, memory and cognition, thereby bridging the gap between computational neuroscience, systems biology and computational intelligence.

  9. Neural Circuitry and Plasticity Mechanisms Underlying Delay Eyeblink Conditioning

    ERIC Educational Resources Information Center

    Freeman, John H.; Steinmetz, Adam B.

    2011-01-01

    Pavlovian eyeblink conditioning has been used extensively as a model system for examining the neural mechanisms underlying associative learning. Delay eyeblink conditioning depends on the intermediate cerebellum ipsilateral to the conditioned eye. Evidence favors a two-site plasticity model within the cerebellum with long-term depression of…

  10. Models of Neural Plasticity and Classroom Practice.

    ERIC Educational Resources Information Center

    Brown, Dawn L.; Wheatley, Grayson H.

    The purpose of this paper is to explore the relationship between constructivism and neural organization. Support is given for a constructivist epistemology in current brain theory. A brief description of constructivism is provided, followed by the implication of this set of beliefs for viewing humans as self-organizing systems. What has been…

  11. Environmental enrichment promotes neural plasticity and cognitive ability in fish.

    PubMed

    Salvanes, Anne Gro Vea; Moberg, Olav; Ebbesson, Lars O E; Nilsen, Tom Ole; Jensen, Knut Helge; Braithwaite, Victoria A

    2013-09-22

    Different kinds of experience during early life can play a significant role in the development of an animal's behavioural phenotype. In natural contexts, this influences behaviours from anti-predator responses to navigation abilities. By contrast, for animals reared in captive environments, the homogeneous nature of their experience tends to reduce behavioural flexibility. Studies with cage-reared rodents indicate that captivity often compromises neural development and neural plasticity. Such neural and behavioural deficits can be problematic if captive-bred animals are being reared with the intention of releasing them as part of a conservation strategy. Over the last decade, there has been growing interest in the use of environmental enrichment to promote behavioural flexibility in animals that are bred for release. Here, we describe the positive effects of environmental enrichment on neural plasticity and cognition in juvenile Atlantic salmon (Salmo salar). Exposing fish to enriched conditions upregulated the forebrain expression of NeuroD1 mRNA and improved learning ability assessed in a spatial task. The addition of enrichment to the captive environment thus promotes neural and behavioural changes that are likely to promote behavioural flexibility and improve post-release survival.

  12. Environmental enrichment promotes neural plasticity and cognitive ability in fish

    PubMed Central

    Salvanes, Anne Gro Vea; Moberg, Olav; Ebbesson, Lars O. E.; Nilsen, Tom Ole; Jensen, Knut Helge; Braithwaite, Victoria A.

    2013-01-01

    Different kinds of experience during early life can play a significant role in the development of an animal's behavioural phenotype. In natural contexts, this influences behaviours from anti-predator responses to navigation abilities. By contrast, for animals reared in captive environments, the homogeneous nature of their experience tends to reduce behavioural flexibility. Studies with cage-reared rodents indicate that captivity often compromises neural development and neural plasticity. Such neural and behavioural deficits can be problematic if captive-bred animals are being reared with the intention of releasing them as part of a conservation strategy. Over the last decade, there has been growing interest in the use of environmental enrichment to promote behavioural flexibility in animals that are bred for release. Here, we describe the positive effects of environmental enrichment on neural plasticity and cognition in juvenile Atlantic salmon (Salmo salar). Exposing fish to enriched conditions upregulated the forebrain expression of NeuroD1 mRNA and improved learning ability assessed in a spatial task. The addition of enrichment to the captive environment thus promotes neural and behavioural changes that are likely to promote behavioural flexibility and improve post-release survival. PMID:23902903

  13. Neural Plasticity in Common Forms of Chronic Headaches

    PubMed Central

    Lai, Tzu-Hsien; Protsenko, Ekaterina; Cheng, Yu-Chen; Loggia, Marco L.; Coppola, Gianluca; Chen, Wei-Ta

    2015-01-01

    Headaches are universal experiences and among the most common disorders. While headache may be physiological in the acute setting, it can become a pathological and persistent condition. The mechanisms underlying the transition from episodic to chronic pain have been the subject of intense study. Using physiological and imaging methods, researchers have identified a number of different forms of neural plasticity associated with migraine and other headaches, including peripheral and central sensitization, and alterations in the endogenous mechanisms of pain modulation. While these changes have been proposed to contribute to headache and pain chronification, some findings are likely the results of repetitive noxious stimulation, such as atrophy of brain areas involved in pain perception and modulation. In this review, we provide a narrative overview of recent advances on the neuroimaging, electrophysiological and genetic aspects of neural plasticity associated with the most common forms of chronic headaches, including migraine, cluster headache, tension-type headache, and medication overuse headache. PMID:26366304

  14. Conservative motor systems, behavioral modulation and neural plasticity.

    PubMed

    Pellis, Sergio M

    2010-12-01

    Neural plasticity is a term that encompasses a vast array of changes in the nervous system in response to a wide range of environmental disturbances. The conservative manner in which nervous systems produce behavior is explored in the act of scratching the head. Whether the scratching is done with the hind leg (flamingos and axis deer) or the hand (spider monkey), it is shown that, when scratching their heads, animals follow a simple rule to avoid making multiple movements simultaneously with different parts of their bodies. Closer inspection of such a computational cost-saving scheme reveals that neural plasticity may best enhance motor performance when it occurs at higher levels of brain organization. The example of how complex social behavior, play fighting, is organized in rats shows that cortical systems can modify the contextual use of species-typical, or well-learned, behavior patterns, rather than producing new behavior patterns.

  15. Habitual Alcohol Seeking: Neural Bases and Possible Relations to Alcohol Use Disorders.

    PubMed

    Corbit, Laura H; Janak, Patricia H

    2016-07-01

    Loss of flexible control over alcohol use may contribute to the development of alcohol use disorders. An increased contribution of response habits to alcohol-related behaviors may help explain this loss of control. Focusing on data from outcome devaluation and Pavlovian-instrumental transfer procedures, we review evidence for loss of goal-directed control over alcohol seeking and consumption drawing from both preclinical findings and clinical data where they exist. Over the course of extended alcohol self-administration and exposure, the performance of alcohol-seeking responses becomes less sensitive to reduction in the value of alcohol and more vulnerable to the influences of alcohol-predictive stimuli. These behavioral changes are accompanied by a shift in the corticostriatal circuits that control responding from circuits centered on the dorsomedial to those centered on the dorsolateral striatum. These changes in behavioral and neural control could help explain failures to abstain from alcohol despite intention to do so. Understanding and ultimately ameliorating these changes will aid development of more effective treatment interventions. PMID:27223341

  16. Habitual Alcohol Seeking: Neural Bases and Possible Relations to Alcohol Use Disorders.

    PubMed

    Corbit, Laura H; Janak, Patricia H

    2016-07-01

    Loss of flexible control over alcohol use may contribute to the development of alcohol use disorders. An increased contribution of response habits to alcohol-related behaviors may help explain this loss of control. Focusing on data from outcome devaluation and Pavlovian-instrumental transfer procedures, we review evidence for loss of goal-directed control over alcohol seeking and consumption drawing from both preclinical findings and clinical data where they exist. Over the course of extended alcohol self-administration and exposure, the performance of alcohol-seeking responses becomes less sensitive to reduction in the value of alcohol and more vulnerable to the influences of alcohol-predictive stimuli. These behavioral changes are accompanied by a shift in the corticostriatal circuits that control responding from circuits centered on the dorsomedial to those centered on the dorsolateral striatum. These changes in behavioral and neural control could help explain failures to abstain from alcohol despite intention to do so. Understanding and ultimately ameliorating these changes will aid development of more effective treatment interventions.

  17. Neural circuitry and plasticity mechanisms underlying delay eyeblink conditioning

    PubMed Central

    Freeman, John H.; Steinmetz, Adam B.

    2011-01-01

    Pavlovian eyeblink conditioning has been used extensively as a model system for examining the neural mechanisms underlying associative learning. Delay eyeblink conditioning depends on the intermediate cerebellum ipsilateral to the conditioned eye. Evidence favors a two-site plasticity model within the cerebellum with long-term depression of parallel fiber synapses on Purkinje cells and long-term potentiation of mossy fiber synapses on neurons in the anterior interpositus nucleus. Conditioned stimulus and unconditioned stimulus inputs arise from the pontine nuclei and inferior olive, respectively, converging in the cerebellar cortex and deep nuclei. Projections from subcortical sensory nuclei to the pontine nuclei that are necessary for eyeblink conditioning are beginning to be identified, and recent studies indicate that there are dynamic interactions between sensory thalamic nuclei and the cerebellum during eyeblink conditioning. Cerebellar output is projected to the magnocellular red nucleus and then to the motor nuclei that generate the blink response(s). Tremendous progress has been made toward determining the neural mechanisms of delay eyeblink conditioning but there are still significant gaps in our understanding of the necessary neural circuitry and plasticity mechanisms underlying cerebellar learning. PMID:21969489

  18. Neural Plastic Effects of Cognitive Training on Aging Brain

    PubMed Central

    Leung, Natalie T. Y.; Tam, Helena M. K.; Chu, Leung W.; Kwok, Timothy C. Y.; Chan, Felix; Lam, Linda C. W.; Woo, Jean; Lee, Tatia M. C.

    2015-01-01

    Increasing research has evidenced that our brain retains a capacity to change in response to experience until late adulthood. This implies that cognitive training can possibly ameliorate age-associated cognitive decline by inducing training-specific neural plastic changes at both neural and behavioral levels. This longitudinal study examined the behavioral effects of a systematic thirteen-week cognitive training program on attention and working memory of older adults who were at risk of cognitive decline. These older adults were randomly assigned to the Cognitive Training Group (n = 109) and the Active Control Group (n = 100). Findings clearly indicated that training induced improvement in auditory and visual-spatial attention and working memory. The training effect was specific to the experience provided because no significant difference in verbal and visual-spatial memory between the two groups was observed. This pattern of findings is consistent with the prediction and the principle of experience-dependent neuroplasticity. Findings of our study provided further support to the notion that the neural plastic potential continues until older age. The baseline cognitive status did not correlate with pre- versus posttraining changes to any cognitive variables studied, suggesting that the initial cognitive status may not limit the neuroplastic potential of the brain at an old age. PMID:26417460

  19. Mice lacking the adenosine A1 receptor have normal spatial learning and plasticity in the CA1 region of the hippocampus, but they habituate more slowly.

    PubMed

    Giménez-Llort, Lydia; Masino, Susan A; Diao, Lihong; Fernández-Teruel, Alberto; Tobeña, Adolf; Halldner, Linda; Fredholm, Bertil B

    2005-07-01

    Using mice with a targeted disruption of the adenosine A1 receptor (A1R), we examined the role of A1Rs in hippocampal long-term potentiation (LTP), long-term depression (LTD), and memory formation. Recordings from the Shaffer collateral-CA1 pathway of hippocampal slices from adult mice showed no differences between theta burst and tetanic stimulation-induced LTP in adenosine A1 receptor knockout (A1R-/-), heterozygote (A1R+/-), and wildtype (A1R+/+) mice. However, paired pulse facilitation was impaired significantly in A1R-/- slices as compared to A1R+/+ slices. LTD in the CA1 region was unaffected by the genetic manipulation. The three genotypes showed similar memory acquisition patterns when assessed for spatial reference and working memory in the Morris water maze tasks at 9 months of age. However, 10 months later A1R-/- mice showed some deficits in the 6-arm radial tunnel maze test. The latter appeared, however, not due to memory deficits but to decreased habituation to the test environment. Taken together, we observe normal spatial learning and memory and hippocampal CA1 synaptic plasticity in adult adenosine A1R knockout mice, but find modifications in arousal-related processes, including habituation, in this knockout model. PMID:15858837

  20. Rapid neural circuit switching mediated by synaptic plasticity during neural morphallactic regeneration.

    PubMed

    Lybrand, Zane R; Zoran, Mark J

    2012-09-01

    The aquatic oligochaete, Lumbriculus variegatus (Lumbriculidae), undergoes a rapid regenerative transformation of its neural circuits following body fragmentation. This type of nervous system plasticity, called neural morphallaxis, involves the remodeling of the giant fiber pathways that mediate rapid head and tail withdrawal behaviors. Extra- and intracellular electrophysiological recordings demonstrated that changes in cellular properties and synaptic connections underlie neurobehavioral plasticity during morphallaxis. Sensory-to-giant interneuron connections, undetectable prior to body injury, emerged within hours of segment amputation. The appearance of functional synaptic transmission was followed by interneuron activation, coupling of giant fiber spiking to motor outputs and overt segmental shortening. The onset of morphallactic plasticity varied along the body axis and emerged more rapidly in segments closer to regions of sensory field overlap between the two giant fiber pathways. The medial and lateral giant fibers were simultaneously activated during a transient phase of network remodeling. Thus, synaptic plasticity at sensory-to-giant interneuron connections mediates escape circuit morphallaxis in this regenerating annelid worm. PMID:22021133

  1. A Genetic Screen for Olfactory Habituation Mutations in Drosophila: Analysis of Novel Foraging Alleles and an Underlying Neural Circuit

    PubMed Central

    Eddison, Mark; Belay, Amsale T.; Sokolowski, Marla B.; Heberlein, Ulrike

    2012-01-01

    Habituation is a form of non-associative learning that enables animals to reduce their reaction to repeated harmless stimuli. When exposed to ethanol vapor, Drosophila show an olfactory-mediated startle response characterized by a transient increase in locomotor activity. Upon repeated exposures, this olfactory startle attenuates with the characteristics of habituation. Here we describe the results of a genetic screen to identify olfactory startle habituation (OSH) mutants. One mutation is a transcript specific allele of foraging (for) encoding a cGMP-dependent kinase. We show this allele of for reduces expression of a for-T1 isoform expressed in the head and functions normally to inhibit OSH. We localize for-T1 function to a limited set of neurons that include olfactory receptor neurons (ORNs) and the mushroom body (MB). Overexpression of for-T1 in ORNs inhibits OSH, an effect also seen upon synaptic silencing of the ORNs; for-T1 may therefore function in ORNs to decrease synaptic release upon repeated exposure to ethanol vapor. Overall, this work contributes to our understanding of the genes and neurons underlying olfactory habituation in Drosophila. PMID:23284741

  2. NEURAL PLASTICITY, HUMAN GENETICS, AND RISK FOR ALCOHOL DEPENDENCE

    PubMed Central

    Hill, Shirley Y.

    2013-01-01

    Opportunities for advances in the neurobiology of alcohol dependence have been facilitated by the development of sophisticated neurophysiological and neuroimaging techniques that allow us to have a window on developmental changes in brain structure and function. The search for genes that may increase susceptibility to alcohol dependence has been greatly facilitated by the recognition that intermediate phenotypes, sometimes referred to as endophenotypes. may be closer to the genetic variation than is the more complex alcohol dependence phenotype. This chapter will review the evidence that the brain is highly plastic, exhibiting major postnatal changes, especially during adolescence, in neural circuits that appear to influence addiction susceptibility. This chapter will suggest that heritable aspects of brain structure and function that are seen developmentally may be an important endophenotypic characteristic associated with familial risk for developing alcohol dependence. Finally, a review of studies showing associations between brain structural and functional characteristics and specific genes will be offered. PMID:20813240

  3. Remodeling myelination: implications for mechanisms of neural plasticity.

    PubMed

    Chang, Kae-Jiun; Redmond, Stephanie A; Chan, Jonah R

    2016-02-01

    One of the most significant paradigm shifts in membrane remodeling is the emerging view that membrane transformation is not exclusively controlled by cytoskeletal rearrangement, but also by biophysical constraints, adhesive forces, membrane curvature and compaction. One of the most exquisite examples of membrane remodeling is myelination. The advent of myelin was instrumental in advancing the nervous system during vertebrate evolution. With more rapid and efficient communication between neurons, faster and more complex computations could be performed in a given time and space. Our knowledge of how myelin-forming oligodendrocytes select and wrap axons has been limited by insufficient spatial and temporal resolution. By virtue of recent technological advances, progress has clarified longstanding controversies in the field. Here we review insights into myelination, from target selection to axon wrapping and membrane compaction, and discuss how understanding these processes has unexpectedly opened new avenues of insight into myelination-centered mechanisms of neural plasticity.

  4. Neural plasticity associated with recently versus often heard objects.

    PubMed

    Bourquin, Nathalie M-P; Spierer, Lucas; Murray, Micah M; Clarke, Stephanie

    2012-09-01

    In natural settings the same sound source is often heard repeatedly, with variations in spectro-temporal and spatial characteristics. We investigated how such repetitions influence sound representations and in particular how auditory cortices keep track of recently vs. often heard objects. A set of 40 environmental sounds was presented twice, i.e. as prime and as repeat, while subjects categorized the corresponding sound sources as living vs. non-living. Electrical neuroimaging analyses were applied to auditory evoked potentials (AEPs) comparing primes vs. repeats (effect of presentation) and the four experimental sections. Dynamic analysis of distributed source estimations revealed i) a significant main effect of presentation within the left temporal convexity at 164-215 ms post-stimulus onset; and ii) a significant main effect of section in the right temporo-parietal junction at 166-213 ms. A 3-way repeated measures ANOVA (hemisphere×presentation×section) applied to neural activity of the above clusters during the common time window confirmed the specificity of the left hemisphere for the effect of presentation, but not that of the right hemisphere for the effect of section. In conclusion, spatio-temporal dynamics of neural activity encode the temporal history of exposure to sound objects. Rapidly occurring plastic changes within the semantic representations of the left hemisphere keep track of objects heard a few seconds before, independent of the more general sound exposure history. Progressively occurring and more long-lasting plastic changes occurring predominantly within right hemispheric networks, which are known to code for perceptual, semantic and spatial aspects of sound objects, keep track of multiple exposures. PMID:22561412

  5. On Aerobic Exercise and Behavioral and Neural Plasticity

    PubMed Central

    Swain, Rodney A.; Berggren, Kiersten L.; Kerr, Abigail L.; Patel, Ami; Peplinski, Caitlin; Sikorski, Angela M.

    2012-01-01

    Aerobic exercise promotes rapid and profound alterations in the brain. Depending upon the pattern and duration of exercise, these changes in the brain may extend beyond traditional motor areas to regions and structures normally linked to learning, cognition, and emotion. Exercise-induced alterations may include changes in blood flow, hormone and growth factor release, receptor expression, angiogenesis, apoptosis, neurogenesis, and synaptogenesis. Together, we believe that these changes underlie elevations of mood and prompt the heightened behavioral plasticity commonly observed following adoption of a chronic exercise regimen. In the following paper, we will explore both the psychological and psychobiological literatures relating to exercise effects on brain in both human and non-human animals and will attempt to link plastic changes in these neural structures to modifications in learned behavior and emotional expression. In addition, we will explore the therapeutic potential of exercise given recent reports that aerobic exercise may serve as a neuroprotectant and can also slow cognitive decline during normal and pathological aging. PMID:24961267

  6. Rehabilitation with Poststroke Motor Recovery: A Review with a Focus on Neural Plasticity

    PubMed Central

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2013-01-01

    Motor recovery after stroke is related to neural plasticity, which involves developing new neuronal interconnections, acquiring new functions, and compensating for impairment. However, neural plasticity is impaired in the stroke-affected hemisphere. Therefore, it is important that motor recovery therapies facilitate neural plasticity to compensate for functional loss. Stroke rehabilitation programs should include meaningful, repetitive, intensive, and task-specific movement training in an enriched environment to promote neural plasticity and motor recovery. Various novel stroke rehabilitation techniques for motor recovery have been developed based on basic science and clinical studies of neural plasticity. However, the effectiveness of rehabilitative interventions among patients with stroke varies widely because the mechanisms underlying motor recovery are heterogeneous. Neurophysiological and neuroimaging studies have been developed to evaluate the heterogeneity of mechanisms underlying motor recovery for effective rehabilitation interventions after stroke. Here, we review novel stroke rehabilitation techniques associated with neural plasticity and discuss individualized strategies to identify appropriate therapeutic goals, prevent maladaptive plasticity, and maximize functional gain in patients with stroke. PMID:23738231

  7. Self-control of chaos in neural circuits with plastic electrical synapses

    NASA Astrophysics Data System (ADS)

    Zhigulin, V. P.; Rabinovich, M. I.

    2004-10-01

    Two kinds of connections are known to exist in neural circuits: electrical (also called gap junctions) and chemical. Whereas chemical synapses are known to be plastic (i. e., modifiable), but slow, electrical transmission through gap junctions is not modifiable, but is very fast. We suggest the new artificial synapse that combines the best properties of both: the fast reaction of a gap junction and the plasticity of a chemical synapse. Such a plastic electrical synapse can be used in hybrid neural circuits and for the development of neural prosthetics, i.e., implanted devices that can interact with the real nervous system. Based on the computer modelling we show that such a plastic electrical synapse regularizes chaos in the minimal neural circuit consisting of two chaotic bursting neurons.

  8. Translating Principles of Neural Plasticity into Research on Speech Motor Control Recovery and Rehabilitation

    ERIC Educational Resources Information Center

    Ludlow, Christy L.; Hoit, Jeannette; Kent, Raymond; Ramig, Lorraine O.; Shrivastav, Rahul; Strand, Edythe; Yorkston, Kathryn; Sapienza, Christine M.

    2008-01-01

    Purpose: To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders. Method: A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural…

  9. Neuron-Glia Interactions in Neural Plasticity: Contributions of Neural Extracellular Matrix and Perineuronal Nets.

    PubMed

    Dzyubenko, Egor; Gottschling, Christine; Faissner, Andreas

    2016-01-01

    Synapses are specialized structures that mediate rapid and efficient signal transmission between neurons and are surrounded by glial cells. Astrocytes develop an intimate association with synapses in the central nervous system (CNS) and contribute to the regulation of ion and neurotransmitter concentrations. Together with neurons, they shape intercellular space to provide a stable milieu for neuronal activity. Extracellular matrix (ECM) components are synthesized by both neurons and astrocytes and play an important role in the formation, maintenance, and function of synapses in the CNS. The components of the ECM have been detected near glial processes, which abut onto the CNS synaptic unit, where they are part of the specialized macromolecular assemblies, termed perineuronal nets (PNNs). PNNs have originally been discovered by Golgi and represent a molecular scaffold deposited in the interface between the astrocyte and subsets of neurons in the vicinity of the synapse. Recent reports strongly suggest that PNNs are tightly involved in the regulation of synaptic plasticity. Moreover, several studies have implicated PNNs and the neural ECM in neuropsychiatric diseases. Here, we highlight current concepts relating to neural ECM and PNNs and describe an in vitro approach that allows for the investigation of ECM functions for synaptogenesis.

  10. Neuron-Glia Interactions in Neural Plasticity: Contributions of Neural Extracellular Matrix and Perineuronal Nets

    PubMed Central

    Dzyubenko, Egor; Gottschling, Christine

    2016-01-01

    Synapses are specialized structures that mediate rapid and efficient signal transmission between neurons and are surrounded by glial cells. Astrocytes develop an intimate association with synapses in the central nervous system (CNS) and contribute to the regulation of ion and neurotransmitter concentrations. Together with neurons, they shape intercellular space to provide a stable milieu for neuronal activity. Extracellular matrix (ECM) components are synthesized by both neurons and astrocytes and play an important role in the formation, maintenance, and function of synapses in the CNS. The components of the ECM have been detected near glial processes, which abut onto the CNS synaptic unit, where they are part of the specialized macromolecular assemblies, termed perineuronal nets (PNNs). PNNs have originally been discovered by Golgi and represent a molecular scaffold deposited in the interface between the astrocyte and subsets of neurons in the vicinity of the synapse. Recent reports strongly suggest that PNNs are tightly involved in the regulation of synaptic plasticity. Moreover, several studies have implicated PNNs and the neural ECM in neuropsychiatric diseases. Here, we highlight current concepts relating to neural ECM and PNNs and describe an in vitro approach that allows for the investigation of ECM functions for synaptogenesis. PMID:26881114

  11. Using brain–computer interfaces to induce neural plasticity and restore function

    PubMed Central

    Grosse-Wentrup, Moritz; Mattia, Donatella; Oweiss, Karim

    2015-01-01

    Analyzing neural signals and providing feedback in realtime is one of the core characteristics of a brain–computer interface (BCI). As this feature may be employed to induce neural plasticity, utilizing BCI technology for therapeutic purposes is increasingly gaining popularity in the BCI community. In this paper, we discuss the state-of-the-art of research on this topic, address the principles of and challenges in inducing neural plasticity by means of a BCI, and delineate the problems of study design and outcome evaluation arising in this context. We conclude with a list of open questions and recommendations for future research in this field. PMID:21436534

  12. Using brain-computer interfaces to induce neural plasticity and restore function

    NASA Astrophysics Data System (ADS)

    Grosse-Wentrup, Moritz; Mattia, Donatella; Oweiss, Karim

    2011-04-01

    Analyzing neural signals and providing feedback in realtime is one of the core characteristics of a brain-computer interface (BCI). As this feature may be employed to induce neural plasticity, utilizing BCI technology for therapeutic purposes is increasingly gaining popularity in the BCI community. In this paper, we discuss the state-of-the-art of research on this topic, address the principles of and challenges in inducing neural plasticity by means of a BCI, and delineate the problems of study design and outcome evaluation arising in this context. We conclude with a list of open questions and recommendations for future research in this field.

  13. Habituation of reinforcer effectiveness

    PubMed Central

    Lloyd, David R.; Medina, Douglas J.; Hawk, Larry W.; Fosco, Whitney D.; Richards, Jerry B.

    2014-01-01

    In this paper we propose an integrative model of habituation of reinforcer effectiveness (HRE) that links behavioral- and neural-based explanations of reinforcement. We argue that HRE is a fundamental property of reinforcing stimuli. Most reinforcement models implicitly suggest that the effectiveness of a reinforcer is stable across repeated presentations. In contrast, an HRE approach predicts decreased effectiveness due to repeated presentation. We argue that repeated presentation of reinforcing stimuli decreases their effectiveness and that these decreases are described by the behavioral characteristics of habituation (McSweeney and Murphy, 2009; Rankin etal., 2009). We describe a neural model that postulates a positive association between dopamine neurotransmission and HRE. We present evidence that stimulant drugs, which artificially increase dopamine neurotransmission, disrupt (slow) normally occurring HRE and also provide evidence that stimulant drugs have differential effects on operant responding maintained by reinforcers with rapid vs. slow HRE rates. We hypothesize that abnormal HRE due to genetic and/or environmental factors may underlie some behavioral disorders. For example, recent research indicates that slow-HRE is predictive of obesity. In contrast ADHD may reflect “accelerated-HRE.” Consideration of HRE is important for the development of effective reinforcement-based treatments. Finally, we point out that most of the reinforcing stimuli that regulate daily behavior are non-consumable environmental/social reinforcers which have rapid-HRE. The almost exclusive use of consumable reinforcers with slow-HRE in pre-clinical studies with animals may have caused the importance of HRE to be overlooked. Further study of reinforcing stimuli with rapid-HRE is needed in order to understand how habituation and reinforcement interact and regulate behavior. PMID:24409128

  14. The super-Turing computational power of plastic recurrent neural networks.

    PubMed

    Cabessa, Jérémie; Siegelmann, Hava T

    2014-12-01

    We study the computational capabilities of a biologically inspired neural model where the synaptic weights, the connectivity pattern, and the number of neurons can evolve over time rather than stay static. Our study focuses on the mere concept of plasticity of the model so that the nature of the updates is assumed to be not constrained. In this context, we show that the so-called plastic recurrent neural networks (RNNs) are capable of the precise super-Turing computational power--as the static analog neural networks--irrespective of whether their synaptic weights are modeled by rational or real numbers, and moreover, irrespective of whether their patterns of plasticity are restricted to bi-valued updates or expressed by any other more general form of updating. Consequently, the incorporation of only bi-valued plastic capabilities in a basic model of RNNs suffices to break the Turing barrier and achieve the super-Turing level of computation. The consideration of more general mechanisms of architectural plasticity or of real synaptic weights does not further increase the capabilities of the networks. These results support the claim that the general mechanism of plasticity is crucially involved in the computational and dynamical capabilities of biological neural networks. They further show that the super-Turing level of computation reflects in a suitable way the capabilities of brain-like models of computation.

  15. A framework for plasticity implementation on the SpiNNaker neural architecture

    PubMed Central

    Galluppi, Francesco; Lagorce, Xavier; Stromatias, Evangelos; Pfeiffer, Michael; Plana, Luis A.; Furber, Steve B.; Benosman, Ryad B.

    2015-01-01

    Many of the precise biological mechanisms of synaptic plasticity remain elusive, but simulations of neural networks have greatly enhanced our understanding of how specific global functions arise from the massively parallel computation of neurons and local Hebbian or spike-timing dependent plasticity rules. For simulating large portions of neural tissue, this has created an increasingly strong need for large scale simulations of plastic neural networks on special purpose hardware platforms, because synaptic transmissions and updates are badly matched to computing style supported by current architectures. Because of the great diversity of biological plasticity phenomena and the corresponding diversity of models, there is a great need for testing various hypotheses about plasticity before committing to one hardware implementation. Here we present a novel framework for investigating different plasticity approaches on the SpiNNaker distributed digital neural simulation platform. The key innovation of the proposed architecture is to exploit the reconfigurability of the ARM processors inside SpiNNaker, dedicating a subset of them exclusively to process synaptic plasticity updates, while the rest perform the usual neural and synaptic simulations. We demonstrate the flexibility of the proposed approach by showing the implementation of a variety of spike- and rate-based learning rules, including standard Spike-Timing dependent plasticity (STDP), voltage-dependent STDP, and the rate-based BCM rule. We analyze their performance and validate them by running classical learning experiments in real time on a 4-chip SpiNNaker board. The result is an efficient, modular, flexible and scalable framework, which provides a valuable tool for the fast and easy exploration of learning models of very different kinds on the parallel and reconfigurable SpiNNaker system. PMID:25653580

  16. Translating Principles of Neural Plasticity into Research on Speech Motor Control Recovery and Rehabilitation

    PubMed Central

    Ludlow, Christy L.; Hoit, Jeannette; Kent, Raymond; Ramig, Lorraine O.; Shrivastav, Rahul; Strand, Edythe; Yorkston, Kathryn; Sapienza, Christine

    2008-01-01

    Purpose To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders. Method A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural plasticity and discusses possible similarities and differences for application to speech motor control disorders. The possible involvement of neural plasticity in changes in speech production in normalcy, development, aging, and neurological diseases and disorders was considered. This report focuses on the appropriate use of functional and structural neuroimaging and the design of feasibility studies aimed at understanding how brain mechanisms are altered by environmental manipulations such as training and stimulation and how these changes might enhance the future development of rehabilitative methods for persons with speech motor control disorders. Conclusions Increased collaboration with neuroscientists working in clinical research centers addressing human communication disorders might foster research in this area. It is hoped that this paper will encourage future research on speech motor control disorders to address the principles of neural plasticity and their application for rehabilitation. PMID:18230849

  17. On the Relationships between Generative Encodings, Regularity, and Learning Abilities when Evolving Plastic Artificial Neural Networks

    PubMed Central

    Tonelli, Paul; Mouret, Jean-Baptiste

    2013-01-01

    A major goal of bio-inspired artificial intelligence is to design artificial neural networks with abilities that resemble those of animal nervous systems. It is commonly believed that two keys for evolving nature-like artificial neural networks are (1) the developmental process that links genes to nervous systems, which enables the evolution of large, regular neural networks, and (2) synaptic plasticity, which allows neural networks to change during their lifetime. So far, these two topics have been mainly studied separately. The present paper shows that they are actually deeply connected. Using a simple operant conditioning task and a classic evolutionary algorithm, we compare three ways to encode plastic neural networks: a direct encoding, a developmental encoding inspired by computational neuroscience models, and a developmental encoding inspired by morphogen gradients (similar to HyperNEAT). Our results suggest that using a developmental encoding could improve the learning abilities of evolved, plastic neural networks. Complementary experiments reveal that this result is likely the consequence of the bias of developmental encodings towards regular structures: (1) in our experimental setup, encodings that tend to produce more regular networks yield networks with better general learning abilities; (2) whatever the encoding is, networks that are the more regular are statistically those that have the best learning abilities. PMID:24236099

  18. On the relationships between generative encodings, regularity, and learning abilities when evolving plastic artificial neural networks.

    PubMed

    Tonelli, Paul; Mouret, Jean-Baptiste

    2013-01-01

    A major goal of bio-inspired artificial intelligence is to design artificial neural networks with abilities that resemble those of animal nervous systems. It is commonly believed that two keys for evolving nature-like artificial neural networks are (1) the developmental process that links genes to nervous systems, which enables the evolution of large, regular neural networks, and (2) synaptic plasticity, which allows neural networks to change during their lifetime. So far, these two topics have been mainly studied separately. The present paper shows that they are actually deeply connected. Using a simple operant conditioning task and a classic evolutionary algorithm, we compare three ways to encode plastic neural networks: a direct encoding, a developmental encoding inspired by computational neuroscience models, and a developmental encoding inspired by morphogen gradients (similar to HyperNEAT). Our results suggest that using a developmental encoding could improve the learning abilities of evolved, plastic neural networks. Complementary experiments reveal that this result is likely the consequence of the bias of developmental encodings towards regular structures: (1) in our experimental setup, encodings that tend to produce more regular networks yield networks with better general learning abilities; (2) whatever the encoding is, networks that are the more regular are statistically those that have the best learning abilities.

  19. Plasticity in memristive devices for spiking neural networks

    PubMed Central

    Saïghi, Sylvain; Mayr, Christian G.; Serrano-Gotarredona, Teresa; Schmidt, Heidemarie; Lecerf, Gwendal; Tomas, Jean; Grollier, Julie; Boyn, Sören; Vincent, Adrien F.; Querlioz, Damien; La Barbera, Selina; Alibart, Fabien; Vuillaume, Dominique; Bichler, Olivier; Gamrat, Christian; Linares-Barranco, Bernabé

    2015-01-01

    Memristive devices present a new device technology allowing for the realization of compact non-volatile memories. Some of them are already in the process of industrialization. Additionally, they exhibit complex multilevel and plastic behaviors, which make them good candidates for the implementation of artificial synapses in neuromorphic engineering. However, memristive effects rely on diverse physical mechanisms, and their plastic behaviors differ strongly from one technology to another. Here, we present measurements performed on different memristive devices and the opportunities that they provide. We show that they can be used to implement different learning rules whose properties emerge directly from device physics: real time or accelerated operation, deterministic or stochastic behavior, long term or short term plasticity. We then discuss how such devices might be integrated into a complete architecture. These results highlight that there is no unique way to exploit memristive devices in neuromorphic systems. Understanding and embracing device physics is the key for their optimal use. PMID:25784849

  20. Neural Plasticity in Multiple Sclerosis: The Functional and Molecular Background

    PubMed Central

    Ksiazek-Winiarek, Dominika Justyna; Szpakowski, Piotr; Glabinski, Andrzej

    2015-01-01

    Multiple sclerosis is an autoimmune neurodegenerative disorder resulting in motor dysfunction and cognitive decline. The inflammatory and neurodegenerative changes seen in the brains of MS patients lead to progressive disability and increasing brain atrophy. The most common type of MS is characterized by episodes of clinical exacerbations and remissions. This suggests the presence of compensating mechanisms for accumulating damage. Apart from the widely known repair mechanisms like remyelination, another important phenomenon is neuronal plasticity. Initially, neuroplasticity was connected with the developmental stages of life; however, there is now growing evidence confirming that structural and functional reorganization occurs throughout our lifetime. Several functional studies, utilizing such techniques as fMRI, TBS, or MRS, have provided valuable data about the presence of neuronal plasticity in MS patients. CNS ability to compensate for neuronal damage is most evident in RR-MS; however it has been shown that brain plasticity is also preserved in patients with substantial brain damage. Regardless of the numerous studies, the molecular background of neuronal plasticity in MS is still not well understood. Several factors, like IL-1β, BDNF, PDGF, or CB1Rs, have been implicated in functional recovery from the acute phase of MS and are thus considered as potential therapeutic targets. PMID:26229689

  1. Swallowing and Dysphagia Rehabilitation: Translating Principles of Neural Plasticity into Clinically Oriented Evidence

    ERIC Educational Resources Information Center

    Robbins, JoAnne; Butler, Susan G.; Daniels, Stephanie K.; Gross, Roxann Diez; Langmore, Susan; Lazarus, Cathy L.; Martin-Harris, Bonnie; McCabe, Daniel; Musson, Nan; Rosenbek, John

    2008-01-01

    Purpose: This review presents the state of swallowing rehabilitation science as it relates to evidence for neural plastic changes in the brain. The case is made for essential collaboration between clinical and basic scientists to expand the positive influences of dysphagia rehabilitation in synergy with growth in technology and knowledge. The…

  2. Principles of Experience-Dependent Neural Plasticity: Implications for Rehabilitation after Brain Damage

    ERIC Educational Resources Information Center

    Kleim, Jeffrey A.; Jones, Theresa A.

    2008-01-01

    Purpose: This paper reviews 10 principles of experience-dependent neural plasticity and considerations in applying them to the damaged brain. Method: Neuroscience research using a variety of models of learning, neurological disease, and trauma are reviewed from the perspective of basic neuroscientists but in a manner intended to be useful for the…

  3. Neural Plasticity and the Issue of Mimicry Tasks in L2 Pronunciation Studies.

    ERIC Educational Resources Information Center

    Stapp, Yvonne F.

    1999-01-01

    In an investigation of the relationship between mimicry skill and neural plasticity, 28 monolingual Japanese subjects aged 4-17 repeated a list of simple English words containing /r/ and /l/. Analyses were made of individual and age-group scores and of consistency of individuals' pronunciation across word tokens. Results indicated mimicry ability…

  4. Neural circuit remodeling and structural plasticity in the cortex during chronic pain

    PubMed Central

    Kim, Woojin

    2016-01-01

    Damage in the periphery or spinal cord induces maladaptive plastic changes along the somatosensory nervous system from the periphery to the cortex, often leading to chronic pain. Although the role of neural circuit remodeling and structural synaptic plasticity in the 'pain matrix' cortices in chronic pain has been thought as a secondary epiphenomenon to altered nociceptive signaling in the spinal cord, progress in whole brain imaging studies on human patients and animal models has suggested a possibility that plastic changes in cortical neural circuits may actively contribute to chronic pain symptoms. Furthermore, recent development in two-photon microscopy and fluorescence labeling techniques have enabled us to longitudinally trace the structural and functional changes in local circuits, single neurons and even individual synapses in the brain of living animals. These technical advances has started to reveal that cortical structural remodeling following tissue or nerve damage could rapidly occur within days, which are temporally correlated with functional plasticity of cortical circuits as well as the development and maintenance of chronic pain behavior, thereby modifying the previous concept that it takes much longer periods (e.g. months or years). In this review, we discuss the relation of neural circuit plasticity in the 'pain matrix' cortices, such as the anterior cingulate cortex, prefrontal cortex and primary somatosensory cortex, with chronic pain. We also introduce how to apply long-term in vivo two-photon imaging approaches for the study of pathophysiological mechanisms of chronic pain. PMID:26807017

  5. Intrinsic Plasticity for Natural Competition in Koniocortex-Like Neural Networks.

    PubMed

    Peláez, Francisco Javier Ropero; Aguiar-Furucho, Mariana Antonia; Andina, Diego

    2016-08-01

    In this paper, we use the neural property known as intrinsic plasticity to develop neural network models that resemble the koniocortex, the fourth layer of sensory cortices. These models evolved from a very basic two-layered neural network to a complex associative koniocortex network. In the initial network, intrinsic and synaptic plasticity govern the shifting of the activation function, and the modification of synaptic weights, respectively. In this first version, competition is forced, so that the most activated neuron is arbitrarily set to one and the others to zero, while in the second, competition occurs naturally due to inhibition between second layer neurons. In the third version of the network, whose architecture is similar to the koniocortex, competition also occurs naturally owing to the interplay between inhibitory interneurons and synaptic and intrinsic plasticity. A more complex associative neural network was developed based on this basic koniocortex-like neural network, capable of dealing with incomplete patterns and ideally suited to operating similarly to a learning vector quantization network. We also discuss the biological plausibility of the networks and their role in a more complex thalamocortical model.

  6. Brain-controlled neuromuscular stimulation to drive neural plasticity and functional recovery.

    PubMed

    Ethier, C; Gallego, J A; Miller, L E

    2015-08-01

    There is mounting evidence that appropriately timed neuromuscular stimulation can induce neural plasticity and generate functional recovery from motor disorders. This review addresses the idea that coordinating stimulation with a patient's voluntary effort might further enhance neurorehabilitation. Studies in cell cultures and behaving animals have delineated the rules underlying neural plasticity when single neurons are used as triggers. However, the rules governing more complex stimuli and larger networks are less well understood. We argue that functional recovery might be optimized if stimulation were modulated by a brain machine interface, to match the details of the patient's voluntary intent. The potential of this novel approach highlights the need for a better understanding of the complex rules underlying this form of plasticity. PMID:25827275

  7. Brain-Controlled Neuromuscular Stimulation to Drive Neural Plasticity and Functional Recovery

    PubMed Central

    Ethier, C.; Gallego, J.A.; Miller, L.E.

    2015-01-01

    There is mounting evidence that appropriately timed neuromuscular stimulation can induce neural plasticity and generate functional recovery from motor disorders. This review addresses the idea that coordinating stimulation with a patient’s voluntary effort might further enhance neurorehabilitation. Studies in cell cultures and behaving animals have delineated the rules underlying neural plasticity when single neurons are used as triggers. However, the rules governing more complex stimuli and larger networks are less well understood. We argue that functional recovery might be optimized if stimulation were modulated by a brain machine interface, to matched the details of the patient’s voluntary intent. The potential of this novel approach highlights the need for a better understanding of the complex rules underlying this form of plasticity. PMID:25827275

  8. Neural Functions of Matrix Metalloproteinases: Plasticity, Neurogenesis, and Disease

    PubMed Central

    Fujioka, Hiromi; Dairyo, Yusuke; Yasunaga, Kei-ichiro; Emoto, Kazuo

    2012-01-01

    The brain changes in response to experience and altered environment. To do that, the nervous system often remodels the structures of neuronal circuits. This structural plasticity of the neuronal circuits appears to be controlled not only by intrinsic factors, but also by extrinsic mechanisms including modification of the extracellular matrix. Recent studies employing a range of animal models implicate that matrix metalloproteinases regulate multiple aspects of the neuronal development and remodeling in the brain. This paper aims to summarize recent advances of our knowledge on the neuronal functions of matrix metalloproteinases and discuss how they might relate in neuronal disease. PMID:22567285

  9. Large-Scale Simulations of Plastic Neural Networks on Neuromorphic Hardware.

    PubMed

    Knight, James C; Tully, Philip J; Kaplan, Bernhard A; Lansner, Anders; Furber, Steve B

    2016-01-01

    SpiNNaker is a digital, neuromorphic architecture designed for simulating large-scale spiking neural networks at speeds close to biological real-time. Rather than using bespoke analog or digital hardware, the basic computational unit of a SpiNNaker system is a general-purpose ARM processor, allowing it to be programmed to simulate a wide variety of neuron and synapse models. This flexibility is particularly valuable in the study of biological plasticity phenomena. A recently proposed learning rule based on the Bayesian Confidence Propagation Neural Network (BCPNN) paradigm offers a generic framework for modeling the interaction of different plasticity mechanisms using spiking neurons. However, it can be computationally expensive to simulate large networks with BCPNN learning since it requires multiple state variables for each synapse, each of which needs to be updated every simulation time-step. We discuss the trade-offs in efficiency and accuracy involved in developing an event-based BCPNN implementation for SpiNNaker based on an analytical solution to the BCPNN equations, and detail the steps taken to fit this within the limited computational and memory resources of the SpiNNaker architecture. We demonstrate this learning rule by learning temporal sequences of neural activity within a recurrent attractor network which we simulate at scales of up to 2.0 × 104 neurons and 5.1 × 107 plastic synapses: the largest plastic neural network ever to be simulated on neuromorphic hardware. We also run a comparable simulation on a Cray XC-30 supercomputer system and find that, if it is to match the run-time of our SpiNNaker simulation, the super computer system uses approximately 45× more power. This suggests that cheaper, more power efficient neuromorphic systems are becoming useful discovery tools in the study of plasticity in large-scale brain models. PMID:27092061

  10. Large-Scale Simulations of Plastic Neural Networks on Neuromorphic Hardware.

    PubMed

    Knight, James C; Tully, Philip J; Kaplan, Bernhard A; Lansner, Anders; Furber, Steve B

    2016-01-01

    SpiNNaker is a digital, neuromorphic architecture designed for simulating large-scale spiking neural networks at speeds close to biological real-time. Rather than using bespoke analog or digital hardware, the basic computational unit of a SpiNNaker system is a general-purpose ARM processor, allowing it to be programmed to simulate a wide variety of neuron and synapse models. This flexibility is particularly valuable in the study of biological plasticity phenomena. A recently proposed learning rule based on the Bayesian Confidence Propagation Neural Network (BCPNN) paradigm offers a generic framework for modeling the interaction of different plasticity mechanisms using spiking neurons. However, it can be computationally expensive to simulate large networks with BCPNN learning since it requires multiple state variables for each synapse, each of which needs to be updated every simulation time-step. We discuss the trade-offs in efficiency and accuracy involved in developing an event-based BCPNN implementation for SpiNNaker based on an analytical solution to the BCPNN equations, and detail the steps taken to fit this within the limited computational and memory resources of the SpiNNaker architecture. We demonstrate this learning rule by learning temporal sequences of neural activity within a recurrent attractor network which we simulate at scales of up to 2.0 × 104 neurons and 5.1 × 107 plastic synapses: the largest plastic neural network ever to be simulated on neuromorphic hardware. We also run a comparable simulation on a Cray XC-30 supercomputer system and find that, if it is to match the run-time of our SpiNNaker simulation, the super computer system uses approximately 45× more power. This suggests that cheaper, more power efficient neuromorphic systems are becoming useful discovery tools in the study of plasticity in large-scale brain models.

  11. Large-Scale Simulations of Plastic Neural Networks on Neuromorphic Hardware

    PubMed Central

    Knight, James C.; Tully, Philip J.; Kaplan, Bernhard A.; Lansner, Anders; Furber, Steve B.

    2016-01-01

    SpiNNaker is a digital, neuromorphic architecture designed for simulating large-scale spiking neural networks at speeds close to biological real-time. Rather than using bespoke analog or digital hardware, the basic computational unit of a SpiNNaker system is a general-purpose ARM processor, allowing it to be programmed to simulate a wide variety of neuron and synapse models. This flexibility is particularly valuable in the study of biological plasticity phenomena. A recently proposed learning rule based on the Bayesian Confidence Propagation Neural Network (BCPNN) paradigm offers a generic framework for modeling the interaction of different plasticity mechanisms using spiking neurons. However, it can be computationally expensive to simulate large networks with BCPNN learning since it requires multiple state variables for each synapse, each of which needs to be updated every simulation time-step. We discuss the trade-offs in efficiency and accuracy involved in developing an event-based BCPNN implementation for SpiNNaker based on an analytical solution to the BCPNN equations, and detail the steps taken to fit this within the limited computational and memory resources of the SpiNNaker architecture. We demonstrate this learning rule by learning temporal sequences of neural activity within a recurrent attractor network which we simulate at scales of up to 2.0 × 104 neurons and 5.1 × 107 plastic synapses: the largest plastic neural network ever to be simulated on neuromorphic hardware. We also run a comparable simulation on a Cray XC-30 supercomputer system and find that, if it is to match the run-time of our SpiNNaker simulation, the super computer system uses approximately 45× more power. This suggests that cheaper, more power efficient neuromorphic systems are becoming useful discovery tools in the study of plasticity in large-scale brain models. PMID:27092061

  12. The common neural parasite Pseudoloma neurophilia is associated with altered startle response habituation in adult zebrafish (Danio rerio): Implications for the zebrafish as a model organism

    PubMed Central

    Spagnoli, Sean; Xue, Lan; Kent, Michael L.

    2015-01-01

    The zebrafish’s potential as a model for human neurobehavioral research appears nearly limitless despite its relatively recent emergence as an experimental organism. Since the zebrafish has only been part of the research community for a handful of decades, pathogens from its commercial origins continue to plague laboratory stocks. One such pathogen is Pseudoloma neurophilia, a common microparasite in zebrafish laboratories world-wide that generally produces subclinical infections. Given its high prevalence, its predilection for the host’s brain and spinal cord, and the delicate nature of neurobehavioral research, the behavioral consequences of subclinical P. neurophilia infection must be explored. Fish infected via cohabitation were tested for startle response habituation in parallel with controls in a device that administered ten taps over ten minutes along with taps at 18 and 60 minutes to evaluate habituation extinction. After testing, fish were euthanized and evaluated for infection via histopathology. Infected fish had a significantly smaller reduction in startle velocity during habituation compared to uninfected tankmates and controls. Habituation was eliminated in infected and control fish at 18 minutes, whereas exposed negative fish retained partial habituation at 18 minutes. Infection was also associated with enhanced capture evasion: Despite the absence of external symptoms, infected fish tended to be caught later than uninfected fish netted from the same tank. The combination of decreased overall habituation, early extinction of habituation compared to uninfected cohorts, and enhanced netting evasion indicates that P. neurophilia infection is associated with a behavioral phenotype distinct from that of controls and uninfected cohorts. Because of its prevalence in zebrafish facilities, P. neurophilia has the potential to insidiously influence a wide range of neurobehavioral studies if these associations are causative. Rigorous health screening is

  13. The common neural parasite Pseudoloma neurophilia is associated with altered startle response habituation in adult zebrafish (Danio rerio): Implications for the zebrafish as a model organism.

    PubMed

    Spagnoli, Sean; Xue, Lan; Kent, Michael L

    2015-09-15

    The zebrafish's potential as a model for human neurobehavioral research appears nearly limitless despite its relatively recent emergence as an experimental organism. Since the zebrafish has only been part of the research community for a handful of decades, pathogens from its commercial origins continue to plague laboratory stocks. One such pathogen is Pseudoloma neurophilia, a common microparasite in zebrafish laboratories world-wide that generally produces subclinical infections. Given its high prevalence, its predilection for the host's brain and spinal cord, and the delicate nature of neurobehavioral research, the behavioral consequences of subclinical P. neurophilia infection must be explored. Fish infected via cohabitation were tested for startle response habituation in parallel with controls in a device that administered ten taps over 10 min along with taps at 18 and 60 min to evaluate habituation extinction. After testing, fish were euthanized and evaluated for infection via histopathology. Infected fish had a significantly smaller reduction in startle velocity during habituation compared to uninfected tankmates and controls. Habituation was eliminated in infected and control fish at 18 min, whereas exposed negative fish retained partial habituation at 18 min. Infection was also associated with enhanced capture evasion: Despite the absence of external symptoms, infected fish tended to be caught later than uninfected fish netted from the same tank. The combination of decreased overall habituation, early extinction of habituation compared to uninfected cohorts, and enhanced netting evasion indicates that P. neurophilia infection is associated with a behavioral phenotype distinct from that of controls and uninfected cohorts. Because of its prevalence in zebrafish facilities, P. neurophilia has the potential to insidiously influence a wide range of neurobehavioral studies if these associations are causative. Rigorous health screening is therefore vital to the

  14. Emergence of Slow Collective Oscillations in Neural Networks with Spike-Timing Dependent Plasticity

    NASA Astrophysics Data System (ADS)

    Mikkelsen, Kaare; Imparato, Alberto; Torcini, Alessandro

    2013-05-01

    The collective dynamics of excitatory pulse coupled neurons with spike-timing dependent plasticity is studied. The introduction of spike-timing dependent plasticity induces persistent irregular oscillations between strongly and weakly synchronized states, reminiscent of brain activity during slow-wave sleep. We explain the oscillations by a mechanism, the Sisyphus Effect, caused by a continuous feedback between the synaptic adjustments and the coherence in the neural firing. Due to this effect, the synaptic weights have oscillating equilibrium values, and this prevents the system from relaxing into a stationary macroscopic state.

  15. [Structure and function of neural plasticity-related gene products].

    PubMed

    Yamagata, K; Sugiura, H; Suzuki, K

    1998-08-01

    We have isolated novel immediate early genes (IEGs) from the hippocampus by differential cloning techniques. These mRNAs are induced by synaptic activity and translated into proteins that may affect neural function. We have analyzed a variety of "effector" immediate early genes. These mRNAs encode: 1) cytoplasmic proteins, such as cyclooxygenase-2, a small G protein, Rheb, and a cytoskeleton-associated protein, Arc; 2) membrane-bound proteins, such as the cell adhesion protein Arcadlin, and a neurite-outgrowth protein, Neuritin; and 3) a secreted protein, Narp. We hypothesize that physiological stimulation induces "effector" proteins that might strengthen synaptic connections of activated synapses. In contrast, pathological conditions such as epilepsy or drug addiction may accelerate overproduction of these gene products, which cause abnormal synapse formation. Gene targeting and in vivo gene transfer techniques are required to prove this hypothesis. PMID:9866829

  16. Mechanisms for modulation of neural plasticity and axon regeneration by chondroitin sulphate.

    PubMed

    Miyata, Shinji; Kitagawa, Hiroshi

    2015-01-01

    Chondroitin sulphate proteoglycans (CSPGs), consisting of core proteins linked to one or more chondroitin sulphate (CS) chains, are major extracellular matrix (ECM) components of the central nervous system (CNS). Multi-functionality of CSPGs can be explained by the diversity in structure of CS chains that undergo dynamic changes during development and under pathological conditions. CSPGs, together with other ECM components, form mesh-like structures called perineuronal nets around a subset of neurons. Enzymatic digestion or genetic manipulation of CSPGs reactivates neural plasticity in the adult brain and improves regeneration of damaged axons after CNS injury. Recent studies have shown that CSPGs not only act as non-specific physical barriers that prevent rearrangement of synaptic connections but also regulate neural plasticity through specific interaction of CS chains with its binding partners in a manner that depends on the structure of the CS chain.

  17. Axonal processes and neural plasticity.I: Ocular dominance columns.

    PubMed

    Elliott, T; Howarth, C I; Shadbolt, N R

    1996-01-01

    We present two related computational models of ocular dominance column formation. Both address nervous system plasticity in terms of sprouting and retraction of axonal processes rather than changes in synaptic strength implied by synapse-specific Hebbian models. We employ statistical mechanics to simulate changes in the pattern of network connectivity. Our formalism uses the concept of an energy function, which we interpret as related to the levels of target-generated neurotrophins for which afferents compete. In contrast, synapse-specific Hebbian models impose synaptic normalization, for which there is little experimental evidence, in order to induce competition. Our models make many predictions which require experimental investigation. We suggest that the absence of monocular deprivation effects in the optic tectum may be due to a tendency of amphibian retinal ganglion cells to preserve the complexity of their terminal arbors. One model raises the possibility that boundaries separating columns in the mammalian cortex are poorly innervated if they have been formed by complete but asynchronous retinal activation. Both models exhibit a phase transition, suggesting a discontinuity in the transition from a binocular cortex to one possessing ocular dominance columns. Finally, our other model could account for the perpendicularity of ocular dominance columns to the boundary of the primary visual cortex while admitting of less ordered central patterns.

  18. Synchrony arising from a balanced synaptic plasticity in a network of heterogeneous neural oscillators.

    PubMed

    Karbowski, Jan; Ermentrout, G Bard

    2002-03-01

    We investigate the dynamics of a recurrent network of coupled heterogeneous neural oscillators with experimentally observed spike-timing-dependent synaptic plasticity. We show both theoretically and by computer simulations that, in a regime of a balance between synaptic potentiation and depression, the network of such oscillators converges to a stable synchronous state. The stability of this state is fostered by flexible synaptic weights which adjust themselves based on the relative timing of firing of pre- and postsynaptic oscillators.

  19. Training-induced neural plasticity in golf novices.

    PubMed

    Bezzola, Ladina; Mérillat, Susan; Gaser, Christian; Jäncke, Lutz

    2011-08-31

    Previous neuroimaging studies in the field of motor learning have shown that learning a new skill induces specific changes of neural gray and white matter in human brain areas necessary to control the practiced task. Former longitudinal studies investigating motor skill learning have used strict training protocols with little ecological validity rather than physical leisure activities, although there are several retrospective and cross-sectional studies suggesting neuroprotective effects of physical leisure activities. In the present longitudinal MRI study, we used voxel-based morphometry to investigate training-induced gray matter changes in golf novices between the age of 40 and 60 years, an age period when an active life style is assumed to counteract cognitive decline. As a main result, we demonstrate that 40 h of golf practice, performed as a leisure activity with highly individual training protocols, are associated with gray matter increases in a task-relevant cortical network encompassing sensorimotor regions and areas belonging to the dorsal stream. A new and striking result is the relationship between training intensity (time needed to complete the 40 training hours) and structural changes observed in the parieto-occipital junction. Thus, we demonstrate that a physical leisure activity induces training-dependent changes in gray matter and assume that a strict and controlled training protocol is not mandatory for training-induced adaptations of gray matter. PMID:21880905

  20. High quality garbage: A neural network plastic sorter in hardware and software

    SciTech Connect

    Stanton, S.L.; Alam, M.K.; Hebner, G.A.

    1993-09-01

    In order to produce pure polymer streams from post-consumer waste plastics, a quick, accurate and relatively inexpensive method of sorting needs to be implemented. This technology has been demonstrated by using near-infrared spectroscopy reflectance data and neural network classification techniques. Backpropagation neural network routines have been developed to run real-time sortings in the lab, using a laboratory-grade spectrometer. In addition, a new reflectance spectrometer has been developed which is fast enough for commercial use. Initial training and test sets taken with the laboratory instrument show that a network is capable of learning 100% when classifying 5 groups of plastic (HDPE and LDPE combined), and up to 100% when classifying 6 groups. Initial data sets from the new instrument have classified plastics into all seven groups with varying degrees of success. One of the initial networks has been implemented in hardware, for high speed computations, and thus rapid classification. Two neural accelerator systems have been evaluated, one based on the Intel 8017ONX chip, and another on the AT&T ANNA chip.

  1. Dissociating cognitive and sensory neural plasticity in human superior temporal cortex.

    PubMed

    Cardin, Velia; Orfanidou, Eleni; Rönnberg, Jerker; Capek, Cheryl M; Rudner, Mary; Woll, Bencie

    2013-01-01

    Disentangling the effects of sensory and cognitive factors on neural reorganization is fundamental for establishing the relationship between plasticity and functional specialization. Auditory deprivation in humans provides a unique insight into this problem, because the origin of the anatomical and functional changes observed in deaf individuals is not only sensory, but also cognitive, owing to the implementation of visual communication strategies such as sign language and speechreading. Here, we describe a functional magnetic resonance imaging study of individuals with different auditory deprivation and sign language experience. We find that sensory and cognitive experience cause plasticity in anatomically and functionally distinguishable substrates. This suggests that after plastic reorganization, cortical regions adapt to process a different type of input signal, but preserve the nature of the computation they perform, both at a sensory and cognitive level.

  2. Dynamic neural networking as a basis for plasticity in the control of heart rate.

    PubMed

    Kember, G; Armour, J A; Zamir, M

    2013-01-21

    A model is proposed in which the relationship between individual neurons within a neural network is dynamically changing to the effect of providing a measure of "plasticity" in the control of heart rate. The neural network on which the model is based consists of three populations of neurons residing in the central nervous system, the intrathoracic extracardiac nervous system, and the intrinsic cardiac nervous system. This hierarchy of neural centers is used to challenge the classical view that the control of heart rate, a key clinical index, resides entirely in central neuronal command (spinal cord, medulla oblongata, and higher centers). Our results indicate that dynamic networking allows for the possibility of an interplay among the three populations of neurons to the effect of altering the order of control of heart rate among them. This interplay among the three levels of control allows for different neural pathways for the control of heart rate to emerge under different blood flow demands or disease conditions and, as such, it has significant clinical implications because current understanding and treatment of heart rate anomalies are based largely on a single level of control and on neurons acting in unison as a single entity rather than individually within a (plastically) interconnected network. PMID:23041448

  3. Dynamic neural networking as a basis for plasticity in the control of heart rate.

    PubMed

    Kember, G; Armour, J A; Zamir, M

    2013-01-21

    A model is proposed in which the relationship between individual neurons within a neural network is dynamically changing to the effect of providing a measure of "plasticity" in the control of heart rate. The neural network on which the model is based consists of three populations of neurons residing in the central nervous system, the intrathoracic extracardiac nervous system, and the intrinsic cardiac nervous system. This hierarchy of neural centers is used to challenge the classical view that the control of heart rate, a key clinical index, resides entirely in central neuronal command (spinal cord, medulla oblongata, and higher centers). Our results indicate that dynamic networking allows for the possibility of an interplay among the three populations of neurons to the effect of altering the order of control of heart rate among them. This interplay among the three levels of control allows for different neural pathways for the control of heart rate to emerge under different blood flow demands or disease conditions and, as such, it has significant clinical implications because current understanding and treatment of heart rate anomalies are based largely on a single level of control and on neurons acting in unison as a single entity rather than individually within a (plastically) interconnected network.

  4. Synaptic plasticity in a recurrent neural network for versatile and adaptive behaviors of a walking robot.

    PubMed

    Grinke, Eduard; Tetzlaff, Christian; Wörgötter, Florentin; Manoonpong, Poramate

    2015-01-01

    Walking animals, like insects, with little neural computing can effectively perform complex behaviors. For example, they can walk around their environment, escape from corners/deadlocks, and avoid or climb over obstacles. While performing all these behaviors, they can also adapt their movements to deal with an unknown situation. As a consequence, they successfully navigate through their complex environment. The versatile and adaptive abilities are the result of an integration of several ingredients embedded in their sensorimotor loop. Biological studies reveal that the ingredients include neural dynamics, plasticity, sensory feedback, and biomechanics. Generating such versatile and adaptive behaviors for a many degrees-of-freedom (DOFs) walking robot is a challenging task. Thus, in this study, we present a bio-inspired approach to solve this task. Specifically, the approach combines neural mechanisms with plasticity, exteroceptive sensory feedback, and biomechanics. The neural mechanisms consist of adaptive neural sensory processing and modular neural locomotion control. The sensory processing is based on a small recurrent neural network consisting of two fully connected neurons. Online correlation-based learning with synaptic scaling is applied to adequately change the connections of the network. By doing so, we can effectively exploit neural dynamics (i.e., hysteresis effects and single attractors) in the network to generate different turning angles with short-term memory for a walking robot. The turning information is transmitted as descending steering signals to the neural locomotion control which translates the signals into motor actions. As a result, the robot can walk around and adapt its turning angle for avoiding obstacles in different situations. The adaptation also enables the robot to effectively escape from sharp corners or deadlocks. Using backbone joint control embedded in the the locomotion control allows the robot to climb over small obstacles

  5. Synaptic plasticity in a recurrent neural network for versatile and adaptive behaviors of a walking robot.

    PubMed

    Grinke, Eduard; Tetzlaff, Christian; Wörgötter, Florentin; Manoonpong, Poramate

    2015-01-01

    Walking animals, like insects, with little neural computing can effectively perform complex behaviors. For example, they can walk around their environment, escape from corners/deadlocks, and avoid or climb over obstacles. While performing all these behaviors, they can also adapt their movements to deal with an unknown situation. As a consequence, they successfully navigate through their complex environment. The versatile and adaptive abilities are the result of an integration of several ingredients embedded in their sensorimotor loop. Biological studies reveal that the ingredients include neural dynamics, plasticity, sensory feedback, and biomechanics. Generating such versatile and adaptive behaviors for a many degrees-of-freedom (DOFs) walking robot is a challenging task. Thus, in this study, we present a bio-inspired approach to solve this task. Specifically, the approach combines neural mechanisms with plasticity, exteroceptive sensory feedback, and biomechanics. The neural mechanisms consist of adaptive neural sensory processing and modular neural locomotion control. The sensory processing is based on a small recurrent neural network consisting of two fully connected neurons. Online correlation-based learning with synaptic scaling is applied to adequately change the connections of the network. By doing so, we can effectively exploit neural dynamics (i.e., hysteresis effects and single attractors) in the network to generate different turning angles with short-term memory for a walking robot. The turning information is transmitted as descending steering signals to the neural locomotion control which translates the signals into motor actions. As a result, the robot can walk around and adapt its turning angle for avoiding obstacles in different situations. The adaptation also enables the robot to effectively escape from sharp corners or deadlocks. Using backbone joint control embedded in the the locomotion control allows the robot to climb over small obstacles

  6. Synaptic plasticity in a recurrent neural network for versatile and adaptive behaviors of a walking robot

    PubMed Central

    Grinke, Eduard; Tetzlaff, Christian; Wörgötter, Florentin; Manoonpong, Poramate

    2015-01-01

    Walking animals, like insects, with little neural computing can effectively perform complex behaviors. For example, they can walk around their environment, escape from corners/deadlocks, and avoid or climb over obstacles. While performing all these behaviors, they can also adapt their movements to deal with an unknown situation. As a consequence, they successfully navigate through their complex environment. The versatile and adaptive abilities are the result of an integration of several ingredients embedded in their sensorimotor loop. Biological studies reveal that the ingredients include neural dynamics, plasticity, sensory feedback, and biomechanics. Generating such versatile and adaptive behaviors for a many degrees-of-freedom (DOFs) walking robot is a challenging task. Thus, in this study, we present a bio-inspired approach to solve this task. Specifically, the approach combines neural mechanisms with plasticity, exteroceptive sensory feedback, and biomechanics. The neural mechanisms consist of adaptive neural sensory processing and modular neural locomotion control. The sensory processing is based on a small recurrent neural network consisting of two fully connected neurons. Online correlation-based learning with synaptic scaling is applied to adequately change the connections of the network. By doing so, we can effectively exploit neural dynamics (i.e., hysteresis effects and single attractors) in the network to generate different turning angles with short-term memory for a walking robot. The turning information is transmitted as descending steering signals to the neural locomotion control which translates the signals into motor actions. As a result, the robot can walk around and adapt its turning angle for avoiding obstacles in different situations. The adaptation also enables the robot to effectively escape from sharp corners or deadlocks. Using backbone joint control embedded in the the locomotion control allows the robot to climb over small obstacles

  7. Enabling functional neural circuit simulations with distributed computing of neuromodulated plasticity.

    PubMed

    Potjans, Wiebke; Morrison, Abigail; Diesmann, Markus

    2010-01-01

    A major puzzle in the field of computational neuroscience is how to relate system-level learning in higher organisms to synaptic plasticity. Recently, plasticity rules depending not only on pre- and post-synaptic activity but also on a third, non-local neuromodulatory signal have emerged as key candidates to bridge the gap between the macroscopic and the microscopic level of learning. Crucial insights into this topic are expected to be gained from simulations of neural systems, as these allow the simultaneous study of the multiple spatial and temporal scales that are involved in the problem. In particular, synaptic plasticity can be studied during the whole learning process, i.e., on a time scale of minutes to hours and across multiple brain areas. Implementing neuromodulated plasticity in large-scale network simulations where the neuromodulatory signal is dynamically generated by the network itself is challenging, because the network structure is commonly defined purely by the connectivity graph without explicit reference to the embedding of the nodes in physical space. Furthermore, the simulation of networks with realistic connectivity entails the use of distributed computing. A neuromodulated synapse must therefore be informed in an efficient way about the neuromodulatory signal, which is typically generated by a population of neurons located on different machines than either the pre- or post-synaptic neuron. Here, we develop a general framework to solve the problem of implementing neuromodulated plasticity in a time-driven distributed simulation, without reference to a particular implementation language, neuromodulator, or neuromodulated plasticity mechanism. We implement our framework in the simulator NEST and demonstrate excellent scaling up to 1024 processors for simulations of a recurrent network incorporating neuromodulated spike-timing dependent plasticity.

  8. NMDA Receptors Mediate Stimulus-Timing-Dependent Plasticity and Neural Synchrony in the Dorsal Cochlear Nucleus

    PubMed Central

    Stefanescu, Roxana A.; Shore, Susan E.

    2015-01-01

    Auditory information relayed by auditory nerve fibers and somatosensory information relayed by granule cell parallel fibers converge on the fusiform cells (FCs) of the dorsal cochlear nucleus, the first brain station of the auditory pathway. In vitro, parallel fiber synapses on FCs exhibit spike-timing-dependent plasticity with Hebbian learning rules, partially mediated by the NMDA receptor (NMDAr). Well-timed bimodal auditory-somatosensory stimulation, in vivo equivalent of spike-timing-dependent plasticity, can induce stimulus-timing-dependent plasticity (StTDP) of the FCs spontaneous and tone-evoked firing rates. In healthy guinea pigs, the resulting distribution of StTDP learning rules across a FC neural population is dominated by a Hebbian profile while anti-Hebbian, suppressive and enhancing LRs are less frequent. In this study, we investigate in vivo, the NMDAr contribution to FC baseline activity and long term plasticity. We find that blocking the NMDAr decreases the synchronization of FC- spontaneous activity and mediates differential modulation of FC rate-level functions such that low, and high threshold units are more likely to increase, and decrease, respectively, their maximum amplitudes. Three significant alterations in mean learning-rule profiles were identified: transitions from an initial Hebbian profile towards (1) an anti-Hebbian; (2) a suppressive profile; and (3) transitions from an anti-Hebbian to a Hebbian profile. FC units preserving their learning rules showed instead, NMDAr-dependent plasticity to unimodal acoustic stimulation, with persistent depression of tone-evoked responses changing to persistent enhancement following the NMDAr antagonist. These results reveal a crucial role of the NMDAr in mediating FC baseline activity and long-term plasticity which have important implications for signal processing and auditory pathologies related to maladaptive plasticity of dorsal cochlear nucleus circuitry. PMID:26622224

  9. Effects of cellular homeostatic intrinsic plasticity on dynamical and computational properties of biological recurrent neural networks.

    PubMed

    Naudé, Jérémie; Cessac, Bruno; Berry, Hugues; Delord, Bruno

    2013-09-18

    Homeostatic intrinsic plasticity (HIP) is a ubiquitous cellular mechanism regulating neuronal activity, cardinal for the proper functioning of nervous systems. In invertebrates, HIP is critical for orchestrating stereotyped activity patterns. The functional impact of HIP remains more obscure in vertebrate networks, where higher order cognitive processes rely on complex neural dynamics. The hypothesis has emerged that HIP might control the complexity of activity dynamics in recurrent networks, with important computational consequences. However, conflicting results about the causal relationships between cellular HIP, network dynamics, and computational performance have arisen from machine-learning studies. Here, we assess how cellular HIP effects translate into collective dynamics and computational properties in biological recurrent networks. We develop a realistic multiscale model including a generic HIP rule regulating the neuronal threshold with actual molecular signaling pathways kinetics, Dale's principle, sparse connectivity, synaptic balance, and Hebbian synaptic plasticity (SP). Dynamic mean-field analysis and simulations unravel that HIP sets a working point at which inputs are transduced by large derivative ranges of the transfer function. This cellular mechanism ensures increased network dynamics complexity, robust balance with SP at the edge of chaos, and improved input separability. Although critically dependent upon balanced excitatory and inhibitory drives, these effects display striking robustness to changes in network architecture, learning rates, and input features. Thus, the mechanism we unveil might represent a ubiquitous cellular basis for complex dynamics in neural networks. Understanding this robustness is an important challenge to unraveling principles underlying self-organization around criticality in biological recurrent neural networks.

  10. Effects of cellular homeostatic intrinsic plasticity on dynamical and computational properties of biological recurrent neural networks.

    PubMed

    Naudé, Jérémie; Cessac, Bruno; Berry, Hugues; Delord, Bruno

    2013-09-18

    Homeostatic intrinsic plasticity (HIP) is a ubiquitous cellular mechanism regulating neuronal activity, cardinal for the proper functioning of nervous systems. In invertebrates, HIP is critical for orchestrating stereotyped activity patterns. The functional impact of HIP remains more obscure in vertebrate networks, where higher order cognitive processes rely on complex neural dynamics. The hypothesis has emerged that HIP might control the complexity of activity dynamics in recurrent networks, with important computational consequences. However, conflicting results about the causal relationships between cellular HIP, network dynamics, and computational performance have arisen from machine-learning studies. Here, we assess how cellular HIP effects translate into collective dynamics and computational properties in biological recurrent networks. We develop a realistic multiscale model including a generic HIP rule regulating the neuronal threshold with actual molecular signaling pathways kinetics, Dale's principle, sparse connectivity, synaptic balance, and Hebbian synaptic plasticity (SP). Dynamic mean-field analysis and simulations unravel that HIP sets a working point at which inputs are transduced by large derivative ranges of the transfer function. This cellular mechanism ensures increased network dynamics complexity, robust balance with SP at the edge of chaos, and improved input separability. Although critically dependent upon balanced excitatory and inhibitory drives, these effects display striking robustness to changes in network architecture, learning rates, and input features. Thus, the mechanism we unveil might represent a ubiquitous cellular basis for complex dynamics in neural networks. Understanding this robustness is an important challenge to unraveling principles underlying self-organization around criticality in biological recurrent neural networks. PMID:24048833

  11. Synaptic plasticity, neural circuits, and the emerging role of altered short-term information processing in schizophrenia

    PubMed Central

    Crabtree, Gregg W.; Gogos, Joseph A.

    2014-01-01

    Synaptic plasticity alters the strength of information flow between presynaptic and postsynaptic neurons and thus modifies the likelihood that action potentials in a presynaptic neuron will lead to an action potential in a postsynaptic neuron. As such, synaptic plasticity and pathological changes in synaptic plasticity impact the synaptic computation which controls the information flow through the neural microcircuits responsible for the complex information processing necessary to drive adaptive behaviors. As current theories of neuropsychiatric disease suggest that distinct dysfunctions in neural circuit performance may critically underlie the unique symptoms of these diseases, pathological alterations in synaptic plasticity mechanisms may be fundamental to the disease process. Here we consider mechanisms of both short-term and long-term plasticity of synaptic transmission and their possible roles in information processing by neural microcircuits in both health and disease. As paradigms of neuropsychiatric diseases with strongly implicated risk genes, we discuss the findings in schizophrenia and autism and consider the alterations in synaptic plasticity and network function observed in both human studies and genetic mouse models of these diseases. Together these studies have begun to point toward a likely dominant role of short-term synaptic plasticity alterations in schizophrenia while dysfunction in autism spectrum disorders (ASDs) may be due to a combination of both short-term and long-term synaptic plasticity alterations. PMID:25505409

  12. Habituation Assessment in Infancy

    ERIC Educational Resources Information Center

    Thomas, Hoben; Gilmore, Rick O.

    2004-01-01

    Infant-control habituation methodology, although serving the research community well, has never been carefully analyzed. A main use is to equate infants in their level of habituation prior to experimental manipulations in a posthabituation phase. When studied analytically and with simulation, it is found to have serious difficulties. It…

  13. Unsupervised discrimination of patterns in spiking neural networks with excitatory and inhibitory synaptic plasticity

    PubMed Central

    Srinivasa, Narayan; Cho, Youngkwan

    2014-01-01

    A spiking neural network model is described for learning to discriminate among spatial patterns in an unsupervised manner. The network anatomy consists of source neurons that are activated by external inputs, a reservoir that resembles a generic cortical layer with an excitatory-inhibitory (EI) network and a sink layer of neurons for readout. Synaptic plasticity in the form of STDP is imposed on all the excitatory and inhibitory synapses at all times. While long-term excitatory STDP enables sparse and efficient learning of the salient features in inputs, inhibitory STDP enables this learning to be stable by establishing a balance between excitatory and inhibitory currents at each neuron in the network. The synaptic weights between source and reservoir neurons form a basis set for the input patterns. The neural trajectories generated in the reservoir due to input stimulation and lateral connections between reservoir neurons can be readout by the sink layer neurons. This activity is used for adaptation of synapses between reservoir and sink layer neurons. A new measure called the discriminability index (DI) is introduced to compute if the network can discriminate between old patterns already presented in an initial training session. The DI is also used to compute if the network adapts to new patterns without losing its ability to discriminate among old patterns. The final outcome is that the network is able to correctly discriminate between all patterns—both old and new. This result holds as long as inhibitory synapses employ STDP to continuously enable current balance in the network. The results suggest a possible direction for future investigation into how spiking neural networks could address the stability-plasticity question despite having continuous synaptic plasticity. PMID:25566045

  14. Unsupervised discrimination of patterns in spiking neural networks with excitatory and inhibitory synaptic plasticity.

    PubMed

    Srinivasa, Narayan; Cho, Youngkwan

    2014-01-01

    A spiking neural network model is described for learning to discriminate among spatial patterns in an unsupervised manner. The network anatomy consists of source neurons that are activated by external inputs, a reservoir that resembles a generic cortical layer with an excitatory-inhibitory (EI) network and a sink layer of neurons for readout. Synaptic plasticity in the form of STDP is imposed on all the excitatory and inhibitory synapses at all times. While long-term excitatory STDP enables sparse and efficient learning of the salient features in inputs, inhibitory STDP enables this learning to be stable by establishing a balance between excitatory and inhibitory currents at each neuron in the network. The synaptic weights between source and reservoir neurons form a basis set for the input patterns. The neural trajectories generated in the reservoir due to input stimulation and lateral connections between reservoir neurons can be readout by the sink layer neurons. This activity is used for adaptation of synapses between reservoir and sink layer neurons. A new measure called the discriminability index (DI) is introduced to compute if the network can discriminate between old patterns already presented in an initial training session. The DI is also used to compute if the network adapts to new patterns without losing its ability to discriminate among old patterns. The final outcome is that the network is able to correctly discriminate between all patterns-both old and new. This result holds as long as inhibitory synapses employ STDP to continuously enable current balance in the network. The results suggest a possible direction for future investigation into how spiking neural networks could address the stability-plasticity question despite having continuous synaptic plasticity.

  15. Plasticity in the neural coding of auditory space in the mammalian brain

    PubMed Central

    King, Andrew J.; Parsons, Carl H.; Moore, David R.

    2000-01-01

    Sound localization relies on the neural processing of monaural and binaural spatial cues that arise from the way sounds interact with the head and external ears. Neurophysiological studies of animals raised with abnormal sensory inputs show that the map of auditory space in the superior colliculus is shaped during development by both auditory and visual experience. An example of this plasticity is provided by monaural occlusion during infancy, which leads to compensatory changes in auditory spatial tuning that tend to preserve the alignment between the neural representations of visual and auditory space. Adaptive changes also take place in sound localization behavior, as demonstrated by the fact that ferrets raised and tested with one ear plugged learn to localize as accurately as control animals. In both cases, these adjustments may involve greater use of monaural spectral cues provided by the other ear. Although plasticity in the auditory space map seems to be restricted to development, adult ferrets show some recovery of sound localization behavior after long-term monaural occlusion. The capacity for behavioral adaptation is, however, task dependent, because auditory spatial acuity and binaural unmasking (a measure of the spatial contribution to the “cocktail party effect”) are permanently impaired by chronically plugging one ear, both in infancy but especially in adulthood. Experience-induced plasticity allows the neural circuitry underlying sound localization to be customized to individual characteristics, such as the size and shape of the head and ears, and to compensate for natural conductive hearing losses, including those associated with middle ear disease in infancy. PMID:11050215

  16. Histone Deacetylase (HDAC) Inhibitors - Emerging Roles in Neuronal Memory, Learning, Synaptic Plasticity and Neural Regeneration

    PubMed Central

    Ahmad Ganai, Shabir; Ramadoss, Mahalakshmi; Mahadevan, Vijayalakshmi

    2016-01-01

    Epigenetic regulation of neuronal signalling through histone acetylation dictates transcription programs that govern neuronal memory, plasticity and learning paradigms. Histone Acetyl Transferases (HATs) and Histone Deacetylases (HDACs) are antagonistic enzymes that regulate gene expression through acetylation and deacetylation of histone proteins around which DNA is wrapped inside a eukaryotic cell nucleus. The epigenetic control of HDACs and the cellular imbalance between HATs and HDACs dictate disease states and have been implicated in muscular dystrophy, loss of memory, neurodegeneration and autistic disorders. Altering gene expression profiles through inhibition of HDACs is now emerging as a powerful technique in therapy. This review presents evolving applications of HDAC inhibitors as potential drugs in neurological research and therapy. Mechanisms that govern their expression profiles in neuronal signalling, plasticity and learning will be covered. Promising and exciting possibilities of HDAC inhibitors in memory formation, fear conditioning, ischemic stroke and neural regeneration have been detailed. PMID:26487502

  17. Nogo Receptor Signaling Restricts Adult Neural Plasticity by Limiting Synaptic AMPA Receptor Delivery

    PubMed Central

    Jitsuki, Susumu; Nakajima, Waki; Takemoto, Kiwamu; Sano, Akane; Tada, Hirobumi; Takahashi-Jitsuki, Aoi; Takahashi, Takuya

    2016-01-01

    Experience-dependent plasticity is limited in the adult brain, and its molecular and cellular mechanisms are poorly understood. Removal of the myelin-inhibiting signaling protein, Nogo receptor (NgR1), restores adult neural plasticity. Here we found that, in NgR1-deficient mice, whisker experience-driven synaptic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) insertion in the barrel cortex, which is normally complete by 2 weeks after birth, lasts into adulthood. In vivo live imaging by two-photon microscopy revealed more AMPAR on the surface of spines in the adult barrel cortex of NgR1-deficient than on those of wild-type (WT) mice. Furthermore, we observed that whisker stimulation produced new spines in the adult barrel cortex of mutant but not WT mice, and that the newly synthesized spines contained surface AMPAR. These results suggest that Nogo signaling limits plasticity by restricting synaptic AMPAR delivery in coordination with anatomical plasticity. PMID:26472557

  18. Predispositions and plasticity in music and speech learning: neural correlates and implications.

    PubMed

    Zatorre, Robert J

    2013-11-01

    Speech and music are remarkable aspects of human cognition and sensory-motor processing. Cognitive neuroscience has focused on them to understand how brain function and structure are modified by learning. Recent evidence indicates that individual differences in anatomical and functional properties of the neural architecture also affect learning and performance in these domains. Here, neuroimaging findings are reviewed that reiterate evidence of experience-dependent brain plasticity, but also point to the predictive validity of such data in relation to new learning in speech and music domains. Indices of neural sensitivity to certain stimulus features have been shown to predict individual rates of learning; individual network properties of brain activity are especially relevant in this regard, as they may reflect anatomical connectivity. Similarly, numerous studies have shown that anatomical features of auditory cortex and other structures, and their anatomical connectivity, are predictive of new sensory-motor learning ability. Implications of this growing body of literature are discussed.

  19. Self-organized noise resistance of oscillatory neural networks with spike timing-dependent plasticity

    NASA Astrophysics Data System (ADS)

    Popovych, Oleksandr V.; Yanchuk, Serhiy; Tass, Peter A.

    2013-10-01

    Intuitively one might expect independent noise to be a powerful tool for desynchronizing a population of synchronized neurons. We here show that, intriguingly, for oscillatory neural populations with adaptive synaptic weights governed by spike timing-dependent plasticity (STDP) the opposite is true. We found that the mean synaptic coupling in such systems increases dynamically in response to the increase of the noise intensity, and there is an optimal noise level, where the amount of synaptic coupling gets maximal in a resonance-like manner as found for the stochastic or coherence resonances, although the mechanism in our case is different. This constitutes a noise-induced self-organization of the synaptic connectivity, which effectively counteracts the desynchronizing impact of independent noise over a wide range of the noise intensity. Given the attempts to counteract neural synchrony underlying tinnitus with noisers and maskers, our results may be of clinical relevance.

  20. Different propagation speeds of recalled sequences in plastic spiking neural networks

    NASA Astrophysics Data System (ADS)

    Huang, Xuhui; Zheng, Zhigang; Hu, Gang; Wu, Si; Rasch, Malte J.

    2015-03-01

    Neural networks can generate spatiotemporal patterns of spike activity. Sequential activity learning and retrieval have been observed in many brain areas, and e.g. is crucial for coding of episodic memory in the hippocampus or generating temporal patterns during song production in birds. In a recent study, a sequential activity pattern was directly entrained onto the neural activity of the primary visual cortex (V1) of rats and subsequently successfully recalled by a local and transient trigger. It was observed that the speed of activity propagation in coordinates of the retinotopically organized neural tissue was constant during retrieval regardless how the speed of light stimulation sweeping across the visual field during training was varied. It is well known that spike-timing dependent plasticity (STDP) is a potential mechanism for embedding temporal sequences into neural network activity. How training and retrieval speeds relate to each other and how network and learning parameters influence retrieval speeds, however, is not well described. We here theoretically analyze sequential activity learning and retrieval in a recurrent neural network with realistic synaptic short-term dynamics and STDP. Testing multiple STDP rules, we confirm that sequence learning can be achieved by STDP. However, we found that a multiplicative nearest-neighbor (NN) weight update rule generated weight distributions and recall activities that best matched the experiments in V1. Using network simulations and mean-field analysis, we further investigated the learning mechanisms and the influence of network parameters on recall speeds. Our analysis suggests that a multiplicative STDP rule with dominant NN spike interaction might be implemented in V1 since recall speed was almost constant in an NMDA-dominant regime. Interestingly, in an AMPA-dominant regime, neural circuits might exhibit recall speeds that instead follow the change in stimulus speeds. This prediction could be tested in

  1. Plasticity and tuning by visual feedback of the stability of a neural integrator.

    PubMed

    Major, Guy; Baker, Robert; Aksay, Emre; Mensh, Brett; Seung, H Sebastian; Tank, David W

    2004-05-18

    Persistent neural firing is of fundamental importance to working memory and other brain functions because it allows information to be held "online" following an input and to be integrated over time. Many models of persistent activity rely on some kind of positive feedback internal to the neural circuit concerned; however, too much feedback causes runaway firing (instability), and too little results in loss of persistence (leak). This parameter sensitivity leads to the hypothesis that the brain uses an error signal (external feedback) to tune the stability of persistent firing by adjusting the amount of internal feedback. We test this hypothesis by manipulating external visual feedback, a putative sensory error signal, in a model system for persistent firing, the goldfish oculomotor neural integrator. Over tens of minutes to hours, electronically controlled visual feedback consistent with a leaky or unstable integrator can drive the integrator progressively more unstable or leaky, respectively. Eye fixation time constants can be reduced >100-fold to <1 s. Normal visual feedback gradually retunes the integrator back to stability. Changes in the phase of the sinusoidal vestibulo-ocular response are consistent with integrator detuning, as are changes in ocular drift following eye position shifts compensating for brief passive head movements during fixations. Corresponding changes in persistent firing of integrator neurons are presented in the accompanying article. The presence, strength, and reversibility of the plasticity demonstrate that, in this system, external visual feedback plays a vital role in gradually tuning the stability of the neural integrator.

  2. STAT3 signal that mediates the neural plasticity is involved in willed-movement training in focal ischemic rats*

    PubMed Central

    Tang, Qing-ping; Shen, Qin; Wu, Li-xiang; Feng, Xiang-ling; Liu, Hui; Wu, Bei; Huang, Xiao-song; Wang, Gai-qing; Li, Zhong-hao; Liu, Zun-jing

    2016-01-01

    Willed-movement training has been demonstrated to be a promising approach to increase motor performance and neural plasticity in ischemic rats. However, little is known regarding the molecular signals that are involved in neural plasticity following willed-movement training. To investigate the potential signals related to neural plasticity following willed-movement training, littermate rats were randomly assigned into three groups: middle cerebral artery occlusion, environmental modification, and willed-movement training. The infarct volume was measured 18 d after occlusion of the right middle cerebral artery. Reverse transcription-polymerase chain reaction (PCR) and immunofluorescence staining were used to detect the changes in the signal transducer and activator of transcription 3 (STAT3) mRNA and protein, respectively. A chromatin immunoprecipitation was used to investigate whether STAT3 bound to plasticity-related genes, such as brain-derived neurotrophic factor (BDNF), synaptophysin, and protein interacting with C kinase 1 (PICK1). In this study, we demonstrated that STAT3 mRNA and protein were markedly increased following 15-d willed-movement training in the ischemic hemispheres of the treated rats. STAT3 bound to BDNF, PICK1, and synaptophysin promoters in the neocortical cells of rats. These data suggest that the increased STAT3 levels after willed-movement training might play critical roles in the neural plasticity by directly regulating plasticity-related genes. PMID:27381726

  3. Pushing the Limits: Cognitive, Affective, and Neural Plasticity Revealed by an Intensive Multifaceted Intervention.

    PubMed

    Mrazek, Michael D; Mooneyham, Benjamin W; Mrazek, Kaita L; Schooler, Jonathan W

    2016-01-01

    Scientific understanding of how much the adult brain can be shaped by experience requires examination of how multiple influences combine to elicit cognitive, affective, and neural plasticity. Using an intensive multifaceted intervention, we discovered that substantial and enduring improvements can occur in parallel across multiple cognitive and neuroimaging measures in healthy young adults. The intervention elicited substantial improvements in physical health, working memory, standardized test performance, mood, self-esteem, self-efficacy, mindfulness, and life satisfaction. Improvements in mindfulness were associated with increased degree centrality of the insula, greater functional connectivity between insula and somatosensory cortex, and reduced functional connectivity between posterior cingulate cortex (PCC) and somatosensory cortex. Improvements in working memory and reading comprehension were associated with increased degree centrality of a region within the middle temporal gyrus (MTG) that was extensively and predominately integrated with the executive control network. The scope and magnitude of the observed improvements represent the most extensive demonstration to date of the considerable human capacity for change. These findings point to higher limits for rapid and concurrent cognitive, affective, and neural plasticity than is widely assumed. PMID:27047361

  4. Upper Limb Immobilisation: A Neural Plasticity Model with Relevance to Poststroke Motor Rehabilitation

    PubMed Central

    Furlan, Leonardo; Conforto, Adriana Bastos; Cohen, Leonardo G.; Sterr, Annette

    2016-01-01

    Advances in our understanding of the neural plasticity that occurs after hemiparetic stroke have contributed to the formulation of theories of poststroke motor recovery. These theories, in turn, have underpinned contemporary motor rehabilitation strategies for treating motor deficits after stroke, such as upper limb hemiparesis. However, a relative drawback has been that, in general, these strategies are most compatible with the recovery profiles of relatively high-functioning stroke survivors and therefore do not easily translate into benefit to those individuals sustaining low-functioning upper limb hemiparesis, who otherwise have poorer residual function. For these individuals, alternative motor rehabilitation strategies are currently needed. In this paper, we will review upper limb immobilisation studies that have been conducted with healthy adult humans and animals. Then, we will discuss how the findings from these studies could inspire the creation of a neural plasticity model that is likely to be of particular relevance to the context of motor rehabilitation after stroke. For instance, as will be elaborated, such model could contribute to the development of alternative motor rehabilitation strategies for treating poststroke upper limb hemiparesis. The implications of the findings from those immobilisation studies for contemporary motor rehabilitation strategies will also be discussed and perspectives for future research in this arena will be provided as well. PMID:26843992

  5. Upper Limb Immobilisation: A Neural Plasticity Model with Relevance to Poststroke Motor Rehabilitation.

    PubMed

    Furlan, Leonardo; Conforto, Adriana Bastos; Cohen, Leonardo G; Sterr, Annette

    2016-01-01

    Advances in our understanding of the neural plasticity that occurs after hemiparetic stroke have contributed to the formulation of theories of poststroke motor recovery. These theories, in turn, have underpinned contemporary motor rehabilitation strategies for treating motor deficits after stroke, such as upper limb hemiparesis. However, a relative drawback has been that, in general, these strategies are most compatible with the recovery profiles of relatively high-functioning stroke survivors and therefore do not easily translate into benefit to those individuals sustaining low-functioning upper limb hemiparesis, who otherwise have poorer residual function. For these individuals, alternative motor rehabilitation strategies are currently needed. In this paper, we will review upper limb immobilisation studies that have been conducted with healthy adult humans and animals. Then, we will discuss how the findings from these studies could inspire the creation of a neural plasticity model that is likely to be of particular relevance to the context of motor rehabilitation after stroke. For instance, as will be elaborated, such model could contribute to the development of alternative motor rehabilitation strategies for treating poststroke upper limb hemiparesis. The implications of the findings from those immobilisation studies for contemporary motor rehabilitation strategies will also be discussed and perspectives for future research in this arena will be provided as well. PMID:26843992

  6. Pushing the Limits: Cognitive, Affective, and Neural Plasticity Revealed by an Intensive Multifaceted Intervention

    PubMed Central

    Mrazek, Michael D.; Mooneyham, Benjamin W.; Mrazek, Kaita L.; Schooler, Jonathan W.

    2016-01-01

    Scientific understanding of how much the adult brain can be shaped by experience requires examination of how multiple influences combine to elicit cognitive, affective, and neural plasticity. Using an intensive multifaceted intervention, we discovered that substantial and enduring improvements can occur in parallel across multiple cognitive and neuroimaging measures in healthy young adults. The intervention elicited substantial improvements in physical health, working memory, standardized test performance, mood, self-esteem, self-efficacy, mindfulness, and life satisfaction. Improvements in mindfulness were associated with increased degree centrality of the insula, greater functional connectivity between insula and somatosensory cortex, and reduced functional connectivity between posterior cingulate cortex (PCC) and somatosensory cortex. Improvements in working memory and reading comprehension were associated with increased degree centrality of a region within the middle temporal gyrus (MTG) that was extensively and predominately integrated with the executive control network. The scope and magnitude of the observed improvements represent the most extensive demonstration to date of the considerable human capacity for change. These findings point to higher limits for rapid and concurrent cognitive, affective, and neural plasticity than is widely assumed. PMID:27047361

  7. Neural Mechanisms of Brain Plasticity with Complex Cognitive Training in Healthy Seniors

    PubMed Central

    Chapman, Sandra B.; Aslan, Sina; Spence, Jeffrey S.; Hart, John J.; Bartz, Elizabeth K.; Didehbani, Nyaz; Keebler, Molly W.; Gardner, Claire M.; Strain, Jeremy F.; DeFina, Laura F.; Lu, Hanzhang

    2015-01-01

    Complex mental activity induces improvements in cognition, brain function, and structure in animals and young adults. It is not clear to what extent the aging brain is capable of such plasticity. This study expands previous evidence of generalized cognitive gains after mental training in healthy seniors. Using 3 MRI-based measurements, that is, arterial spin labeling MRI, functional connectivity, and diffusion tensor imaging, we examined brain changes across 3 time points pre, mid, and post training (12 weeks) in a randomized sample (n = 37) who received cognitive training versus a control group. We found significant training-related brain state changes at rest; specifically, 1) increases in global and regional cerebral blood flow (CBF), particularly in the default mode network and the central executive network, 2) greater connectivity in these same networks, and 3) increased white matter integrity in the left uncinate demonstrated by an increase in fractional anisotropy. Improvements in cognition were identified along with significant CBF correlates of the cognitive gains. We propose that cognitive training enhances resting-state neural activity and connectivity, increasing the blood supply to these regions via neurovascular coupling. These convergent results provide preliminary evidence that neural plasticity can be harnessed to mitigate brain losses with cognitive training in seniors. PMID:23985135

  8. Learning to Produce Syllabic Speech Sounds via Reward-Modulated Neural Plasticity.

    PubMed

    Warlaumont, Anne S; Finnegan, Megan K

    2016-01-01

    At around 7 months of age, human infants begin to reliably produce well-formed syllables containing both consonants and vowels, a behavior called canonical babbling. Over subsequent months, the frequency of canonical babbling continues to increase. How the infant's nervous system supports the acquisition of this ability is unknown. Here we present a computational model that combines a spiking neural network, reinforcement-modulated spike-timing-dependent plasticity, and a human-like vocal tract to simulate the acquisition of canonical babbling. Like human infants, the model's frequency of canonical babbling gradually increases. The model is rewarded when it produces a sound that is more auditorily salient than sounds it has previously produced. This is consistent with data from human infants indicating that contingent adult responses shape infant behavior and with data from deaf and tracheostomized infants indicating that hearing, including hearing one's own vocalizations, is critical for canonical babbling development. Reward receipt increases the level of dopamine in the neural network. The neural network contains a reservoir with recurrent connections and two motor neuron groups, one agonist and one antagonist, which control the masseter and orbicularis oris muscles, promoting or inhibiting mouth closure. The model learns to increase the number of salient, syllabic sounds it produces by adjusting the base level of muscle activation and increasing their range of activity. Our results support the possibility that through dopamine-modulated spike-timing-dependent plasticity, the motor cortex learns to harness its natural oscillations in activity in order to produce syllabic sounds. It thus suggests that learning to produce rhythmic mouth movements for speech production may be supported by general cortical learning mechanisms. The model makes several testable predictions and has implications for our understanding not only of how syllabic vocalizations develop in

  9. Learning to Produce Syllabic Speech Sounds via Reward-Modulated Neural Plasticity.

    PubMed

    Warlaumont, Anne S; Finnegan, Megan K

    2016-01-01

    At around 7 months of age, human infants begin to reliably produce well-formed syllables containing both consonants and vowels, a behavior called canonical babbling. Over subsequent months, the frequency of canonical babbling continues to increase. How the infant's nervous system supports the acquisition of this ability is unknown. Here we present a computational model that combines a spiking neural network, reinforcement-modulated spike-timing-dependent plasticity, and a human-like vocal tract to simulate the acquisition of canonical babbling. Like human infants, the model's frequency of canonical babbling gradually increases. The model is rewarded when it produces a sound that is more auditorily salient than sounds it has previously produced. This is consistent with data from human infants indicating that contingent adult responses shape infant behavior and with data from deaf and tracheostomized infants indicating that hearing, including hearing one's own vocalizations, is critical for canonical babbling development. Reward receipt increases the level of dopamine in the neural network. The neural network contains a reservoir with recurrent connections and two motor neuron groups, one agonist and one antagonist, which control the masseter and orbicularis oris muscles, promoting or inhibiting mouth closure. The model learns to increase the number of salient, syllabic sounds it produces by adjusting the base level of muscle activation and increasing their range of activity. Our results support the possibility that through dopamine-modulated spike-timing-dependent plasticity, the motor cortex learns to harness its natural oscillations in activity in order to produce syllabic sounds. It thus suggests that learning to produce rhythmic mouth movements for speech production may be supported by general cortical learning mechanisms. The model makes several testable predictions and has implications for our understanding not only of how syllabic vocalizations develop in

  10. Learning to Produce Syllabic Speech Sounds via Reward-Modulated Neural Plasticity

    PubMed Central

    Warlaumont, Anne S.; Finnegan, Megan K.

    2016-01-01

    At around 7 months of age, human infants begin to reliably produce well-formed syllables containing both consonants and vowels, a behavior called canonical babbling. Over subsequent months, the frequency of canonical babbling continues to increase. How the infant’s nervous system supports the acquisition of this ability is unknown. Here we present a computational model that combines a spiking neural network, reinforcement-modulated spike-timing-dependent plasticity, and a human-like vocal tract to simulate the acquisition of canonical babbling. Like human infants, the model’s frequency of canonical babbling gradually increases. The model is rewarded when it produces a sound that is more auditorily salient than sounds it has previously produced. This is consistent with data from human infants indicating that contingent adult responses shape infant behavior and with data from deaf and tracheostomized infants indicating that hearing, including hearing one’s own vocalizations, is critical for canonical babbling development. Reward receipt increases the level of dopamine in the neural network. The neural network contains a reservoir with recurrent connections and two motor neuron groups, one agonist and one antagonist, which control the masseter and orbicularis oris muscles, promoting or inhibiting mouth closure. The model learns to increase the number of salient, syllabic sounds it produces by adjusting the base level of muscle activation and increasing their range of activity. Our results support the possibility that through dopamine-modulated spike-timing-dependent plasticity, the motor cortex learns to harness its natural oscillations in activity in order to produce syllabic sounds. It thus suggests that learning to produce rhythmic mouth movements for speech production may be supported by general cortical learning mechanisms. The model makes several testable predictions and has implications for our understanding not only of how syllabic vocalizations develop

  11. Neural Plasticity and Proliferation in the Generation of Antidepressant Effects: Hippocampal Implication

    PubMed Central

    Pilar-Cuéllar, Fuencisla; Vidal, Rebeca; Díaz, Alvaro; Castro, Elena; dos Anjos, Severiano; Pascual-Brazo, Jesús; Linge, Raquel; Vargas, Veronica; Blanco, Helena; Martínez-Villayandre, Beatriz; Pazos, Ángel; Valdizán, Elsa M.

    2013-01-01

    It is widely accepted that changes underlying depression and antidepressant-like effects involve not only alterations in the levels of neurotransmitters as monoamines and their receptors in the brain, but also structural and functional changes far beyond. During the last two decades, emerging theories are providing new explanations about the neurobiology of depression and the mechanism of action of antidepressant strategies based on cellular changes at the CNS level. The neurotrophic/plasticity hypothesis of depression, proposed more than a decade ago, is now supported by multiple basic and clinical studies focused on the role of intracellular-signalling cascades that govern neural proliferation and plasticity. Herein, we review the state-of-the-art of the changes in these signalling pathways which appear to underlie both depressive disorders and antidepressant actions. We will especially focus on the hippocampal cellularity and plasticity modulation by serotonin, trophic factors as brain-derived neurotrophic factor (BDNF), and vascular endothelial growth factor (VEGF) through intracellular signalling pathways—cAMP, Wnt/β-catenin, and mTOR. Connecting the classic monoaminergic hypothesis with proliferation/neuroplasticity-related evidence is an appealing and comprehensive attempt for improving our knowledge about the neurobiological events leading to depression and associated to antidepressant therapies. PMID:23862076

  12. Cooperation of spike timing-dependent and heterosynaptic plasticities in neural networks: A Fokker-Planck approach

    NASA Astrophysics Data System (ADS)

    Zhu, Liqiang; Lai, Ying-Cheng; Hoppensteadt, Frank C.; He, Jiping

    2006-06-01

    It is believed that both Hebbian and homeostatic mechanisms are essential in neural learning. While Hebbian plasticity selectively modifies synaptic connectivity according to activity experienced, homeostatic plasticity constrains this change so that neural activity is always within reasonable physiological limits. Recent experiments reveal spike timing-dependent plasticity (STDP) as a new type of Hebbian learning with high time precision and heterosynaptic plasticity (HSP) as a new homeostatic mechanism acting directly on synapses. Here, we study the effect of STDP and HSP on randomly connected neural networks. Despite the reported successes of STDP to account for neural activities at the single-cell level, we find that, surprisingly, at the network level, networks trained using STDP alone cannot seem to generate realistic neural activities. For instance, STDP would stipulate that past sensory experience be maintained forever if it is no longer activated. To overcome this difficulty, motivated by the fact that HSP can induce strong competition between sensory experiences, we propose a biophysically plausible learning rule by combining STDP and HSP. Based on the Fokker-Planck theory and extensive numerical computations, we demonstrate that HSP and STDP operated on different time scales can complement each other, resulting in more realistic network activities. Our finding may provide fresh insight into the learning mechanism of the brain.

  13. Habituation and extinction of fear recruit overlapping forebrain structures.

    PubMed

    Furlong, Teri M; Richardson, Rick; McNally, Gavan P

    2016-02-01

    Establishing the neurocircuitry involved in inhibiting fear is important for understanding and treating anxiety disorders. To date, extinction procedures have been predominately used to examine the inhibition of learned fear, where fear is reduced to a conditioned stimulus (CS) by presenting it in the absence of the unconditioned stimulus (US). However, learned fear can also be reduced by habituation procedures where the US is presented in the absence of the CS. Here we used expression of the activity marker c-Fos in rats to compare the recruitment of several forebrain structures following fear habituation and extinction. Following fear conditioning where a tone CS was paired with a loud noise US, fear was then reduced the following day by either presentation of the CS or US alone (i.e. CS extinction or US habituation, respectively). This extinction and habituation training recruited several common structures, including infralimbic cortex, basolateral amygdala, midline thalamus and medial hypothalamus (orexin neurons). Moreover, this overlap was shared when examining the neural correlates of the expression of habituation and extinction, with common recruitment of infralimbic cortex and midline thalamus. However, there were also important differences. Specifically, acquisition of habituation was associated with greater recruitment of prelimbic cortex whereas expression of habituation was associated with greater recruitment of paraventricular thalamus. There was also less recruitment of central amygdala for habituation compared to extinction in the retention phase. These findings indicate that largely overlapping neurocircuitries underlie habituation and fear extinction and imply common mechanisms for reducing fear across different inhibitory treatments.

  14. The Neural Cell Adhesion Molecule-Derived Peptide FGL Facilitates Long-Term Plasticity in the Dentate Gyrus in Vivo

    ERIC Educational Resources Information Center

    Dallerac, Glenn; Zerwas, Meike; Novikova, Tatiana; Callu, Delphine; Leblanc-Veyrac, Pascale; Bock, Elisabeth; Berezin, Vladimir; Rampon, Claire; Doyere, Valerie

    2011-01-01

    The neural cell adhesion molecule (NCAM) is known to play a role in developmental and structural processes but also in synaptic plasticity and memory of the adult animal. Recently, FGL, a NCAM mimetic peptide that binds to the Fibroblast Growth Factor Receptor 1 (FGFR-1), has been shown to have a beneficial impact on normal memory functioning, as…

  15. DNA methyltransferase activity is required for memory-related neural plasticity in the lateral amygdala.

    PubMed

    Maddox, Stephanie A; Watts, Casey S; Schafe, Glenn E

    2014-01-01

    We have previously shown that auditory Pavlovian fear conditioning is associated with an increase in DNA methyltransferase (DNMT) expression in the lateral amygdala (LA) and that intra-LA infusion or bath application of an inhibitor of DNMT activity impairs the consolidation of an auditory fear memory and long-term potentiation (LTP) at thalamic and cortical inputs to the LA, in vitro. In the present study, we use awake behaving neurophysiological techniques to examine the role of DNMT activity in memory-related neurophysiological changes accompanying fear memory consolidation and reconsolidation in the LA, in vivo. We show that auditory fear conditioning results in a training-related enhancement in the amplitude of short-latency auditory-evoked field potentials (AEFPs) in the LA. Intra-LA infusion of a DNMT inhibitor impairs both fear memory consolidation and, in parallel, the consolidation of training-related neural plasticity in the LA; that is, short-term memory (STM) and short-term training-related increases in AEFP amplitude in the LA are intact, while long-term memory (LTM) and long-term retention of training-related increases in AEFP amplitudes are impaired. In separate experiments, we show that intra-LA infusion of a DNMT inhibitor following retrieval of an auditory fear memory has no effect on post-retrieval STM or short-term retention of training-related changes in AEFP amplitude in the LA, but significantly impairs both post-retrieval LTM and long-term retention of AEFP amplitude changes in the LA. These findings are the first to demonstrate the necessity of DNMT activity in the consolidation and reconsolidation of memory-associated neural plasticity, in vivo.

  16. Genetic mapping of habitual substance use, obesity-related traits, responses to mental and physical stress, and heart rate and blood pressure measurements reveals shared genes that are overrepresented in the neural synapse.

    PubMed

    Nikpay, Majid; Šeda, Ondrej; Tremblay, Johanne; Petrovich, Milan; Gaudet, Daniel; Kotchen, Theodore A; Cowley, Allen W; Hamet, Pavel

    2012-06-01

    Links between substance use habits, obesity, stress and the related cardiovascular outcomes can be, in part, because of loci with pleiotropic effects. To investigate this hypothesis, we performed genome-wide mapping in 119 multigenerational families from a population in the Saguenay-Lac-St-Jean region with a known founder effect using 58,000 single-nucleotide polymorphisms and 437 microsatellite markers to identify genetic components of the following factors: habitual alcohol, tobacco and coffee use; response to mental and physical stress; obesity-related traits; and heart rate (HR) and blood pressure (BP) measures. Habitual alcohol and/or tobacco users had attenuated HR responses to mental stress compared with non-users, whereas hypertensive individuals had stronger HR and systolic BP responses to mental stress and a higher obesity index than normotensives. Genetic mappings uncovered numerous shared genes among substance use, stress response, obesity and hemodynamic traits, including CAMK4, CNTN4, DLG2, FHIT, GRID2, ITPR2, NOVA1 and PRKCE, forming network of interacting proteins, sharing synaptic function and display higher and patterned expression profiles in brain-related tissues; moreover, pathway analysis of shared genes pointed to long-term potentiation. Subgroup genetic mappings uncovered additional shared synaptic genes, including CAMK4, CNTN5 and DNM3 (hypertension-specific); CNTN4, DNM3, FHIT and ITPR1 (sex-specific), having protein interactions with genes driven from general analysis. In summary, consistent with the observed phenotypic correlations, we found substantial overlap among genomic determinants of these traits in synapse, which supports the notion that the neural synapse may be a shared interface behind substance use, stress, obesity, HR, BP as well as the observed sex- and hypertension-specific genetic differences.

  17. Genetic mapping of habitual substance use, obesity-related traits, responses to mental and physical stress, and heart rate and blood pressure measurements reveals shared genes that are overrepresented in the neural synapse

    PubMed Central

    Nikpay, Majid; Šeda, Ondrej; Tremblay, Johanne; Petrovich, Milan; Gaudet, Daniel; Kotchen, Theodore A; Cowley, Allen W; Hamet, Pavel

    2012-01-01

    Links between substance use habits, obesity, stress and the related cardiovascular outcomes can be, in part, because of loci with pleiotropic effects. To investigate this hypothesis, we performed genome-wide mapping in 119 multigenerational families from a population in the Saguenay-Lac-St-Jean region with a known founder effect using 58 000 single-nucleotide polymorphisms and 437 microsatellite markers to identify genetic components of the following factors: habitual alcohol, tobacco and coffee use; response to mental and physical stress; obesity-related traits; and heart rate (HR) and blood pressure (BP) measures. Habitual alcohol and/or tobacco users had attenuated HR responses to mental stress compared with non-users, whereas hypertensive individuals had stronger HR and systolic BP responses to mental stress and a higher obesity index than normotensives. Genetic mappings uncovered numerous shared genes among substance use, stress response, obesity and hemodynamic traits, including CAMK4, CNTN4, DLG2, FHIT, GRID2, ITPR2, NOVA1 and PRKCE, forming network of interacting proteins, sharing synaptic function and display higher and patterned expression profiles in brain-related tissues; moreover, pathway analysis of shared genes pointed to long-term potentiation. Subgroup genetic mappings uncovered additional shared synaptic genes, including CAMK4, CNTN5 and DNM3 (hypertension-specific); CNTN4, DNM3, FHIT and ITPR1 (sex-specific), having protein interactions with genes driven from general analysis. In summary, consistent with the observed phenotypic correlations, we found substantial overlap among genomic determinants of these traits in synapse, which supports the notion that the neural synapse may be a shared interface behind substance use, stress, obesity, HR, BP as well as the observed sex- and hypertension-specific genetic differences. PMID:22297481

  18. A Neural Circuit That Controls Cortical State, Plasticity, and the Gain of Sensory Responses in Mouse

    PubMed Central

    Stryker, Michael P.

    2015-01-01

    Neurons in the visual cortex were first found to be exquisitely selective for particular properties of visual stimuli in anesthetized animals, including mice. Studies of alert mice in an apparatus that allowed them to stand or run revealed that locomotion causes a change in cortical state that dramatically increases the magnitude of responses in neurons of the visual cortex without altering selectivity, effectively changing the gain of sensory responses. Locomotion also dramatically enhances adult plasticity in the recovery from long-term visual deprivation. We have studied the elements and operation of the neural circuit responsible for the enhancement of activity and shown that it enhances plasticity even in mice not free to run. The circuit consists of projections ascending from the midbrain locomotor region (MLR) to the basal forebrain, activating cholinergic and perhaps other projections to excite inhibitory interneurons expressing vasoactive intestinal peptide (VIP) in the visual cortex. VIP cells activated by locomotion inhibit interneurons that express somatostatin (SST), thereby disinhibiting the excitatory principal neurons and allowing them to respond more strongly to effective visual stimuli. These findings reveal in alert animals how the ascending reticular activating system described in anesthetized animals 50 years ago operates to control cortical state. PMID:25948638

  19. Chronic pain resolution after a lucid dream: a case for neural plasticity?

    PubMed

    Zappaterra, Mauro; Jim, Lysander; Pangarkar, Sanjog

    2014-03-01

    Chronic pain is often managed using a multidisciplinary, biopsychosocial approach. Interventions targeting the biological, psychological, and social aspects of both the patient and the pain have been demonstrated to provide objective and subjective improvement in chronic pain symptoms. The mechanism by which pain attenuation occurs after these interventions remains to be elucidated. While there is a relatively large body of empirical literature suggesting that functional and structural changes in the peripheral and central nervous systems are key in the development and maintenance of chronic pain states, less is known about changes that take place in the nervous system as a whole after biopsychosocial interventions. Using as a model the unique case of Mr. S, a patient suffering with chronic pain for 22 years who experienced a complete resolution of pain after a lucid dream following 2 years of biopsychosocial treatments, we postulate that central nervous system (CNS) reorganization (i.e., neural plasticity) serves as a possible mechanism for the therapeutic benefit of multidisciplinary treatments, and may set a neural framework for healing, in this case via a lucid dream. PMID:24398162

  20. Chronic pain resolution after a lucid dream: a case for neural plasticity?

    PubMed

    Zappaterra, Mauro; Jim, Lysander; Pangarkar, Sanjog

    2014-03-01

    Chronic pain is often managed using a multidisciplinary, biopsychosocial approach. Interventions targeting the biological, psychological, and social aspects of both the patient and the pain have been demonstrated to provide objective and subjective improvement in chronic pain symptoms. The mechanism by which pain attenuation occurs after these interventions remains to be elucidated. While there is a relatively large body of empirical literature suggesting that functional and structural changes in the peripheral and central nervous systems are key in the development and maintenance of chronic pain states, less is known about changes that take place in the nervous system as a whole after biopsychosocial interventions. Using as a model the unique case of Mr. S, a patient suffering with chronic pain for 22 years who experienced a complete resolution of pain after a lucid dream following 2 years of biopsychosocial treatments, we postulate that central nervous system (CNS) reorganization (i.e., neural plasticity) serves as a possible mechanism for the therapeutic benefit of multidisciplinary treatments, and may set a neural framework for healing, in this case via a lucid dream.

  1. Global familiarity of visual stimuli affects repetition-related neural plasticity but not repetition priming

    PubMed Central

    Soldan, Anja; Zarahn, Eric; Hilton, H. John; Stern, Yaakov

    2007-01-01

    In this study we tested the prediction of the component process model of priming (Henson, 2003) that repetition priming of familiar and unfamiliar objects produces qualitatively different neural repetition effects. In an fMRI study, subjects viewed four repetitions of familiar objects and globally unfamiliar objects with familiar components. Reliable behavioral priming occurred for both item types across the four presentations and was of a similar magnitude for both stimulus types. The imaging data was analyzed using multivariate linear modeling, which permits explicit testing of the hypothesis that the repetition effects for familiar and unfamiliar objects are qualitatively different (i.e., non-scaled versions of one another). The results showed the presence of two qualitatively different latent spatial patterns of repetition effects from presenation one to presentation four for familiar and unfamilar objects, indicating that familiarity with an object’s global structural, semantic, or lexical features is an important factor in priming-related neural plasticity. The first latent spatial pattern strongly weighted regions with a similar repetition effect for both item types. The second pattern strongly weighted regions contributing a repetition suppression effect for the familiar objects and repetition enhancement for the unfamiliar objects, particularly the posterior insula, superior temporal gyrus, precentral gyrus, and cingulate cortex. This differential repetition effect might reflect the formation of novel memory representations for the unfamiliar items, which already exist for the familiar objects, consistent with the component-process model of priming. PMID:17913513

  2. Functional plasticity before the cradle: a review of neural functional imaging in the human fetus.

    PubMed

    Anderson, Amy L; Thomason, Moriah E

    2013-11-01

    The organization of the brain is highly plastic in fetal life. Establishment of healthy neural functional systems during the fetal period is essential to normal growth and development. Across the last several decades, remarkable progress has been made in understanding the development of human fetal functional brain systems. This is largely due to advances in imaging methodologies. Fetal neuroimaging began in the 1950-1970's with fetal electroencephalography (EEG) applied during labor. Later, in the 1980's, magnetoencephalography (MEG) emerged as an effective approach for investigating fetal brain function. Most recently, functional magnetic resonance imaging (fMRI) has arisen as an additional powerful approach for examining fetal brain function. This review will discuss major developmental findings from fetal imaging studies such as the maturation of prenatal sensory system functions, functional hemispheric asymmetry, and sensory-driven neurodevelopment. We describe how with improved imaging and analysis techniques, functional imaging of the fetus has the potential to assess the earliest point of neural maturation and provide insight into the patterning and sequence of normal and abnormal brain development.

  3. Cognitive-affective neural plasticity following active-controlled mindfulness intervention.

    PubMed

    Allen, Micah; Dietz, Martin; Blair, Karina S; van Beek, Martijn; Rees, Geraint; Vestergaard-Poulsen, Peter; Lutz, Antoine; Roepstorff, Andreas

    2012-10-31

    Mindfulness meditation is a set of attention-based, regulatory, and self-inquiry training regimes. Although the impact of mindfulness training (MT) on self-regulation is well established, the neural mechanisms supporting such plasticity are poorly understood. MT is thought to act through interoceptive salience and attentional control mechanisms, but until now conflicting evidence from behavioral and neural measures renders difficult distinguishing their respective roles. To resolve this question we conducted a fully randomized 6 week longitudinal trial of MT, explicitly controlling for cognitive and treatment effects with an active-control group. We measured behavioral metacognition and whole-brain blood oxygenation level-dependent (BOLD) signals using functional MRI during an affective Stroop task before and after intervention in healthy human subjects. Although both groups improved significantly on a response-inhibition task, only the MT group showed reduced affective Stroop conflict. Moreover, the MT group displayed greater dorsolateral prefrontal cortex responses during executive processing, consistent with increased recruitment of top-down mechanisms to resolve conflict. In contrast, we did not observe overall group-by-time interactions on negative affect-related reaction times or BOLD responses. However, only participants with the greatest amount of MT practice showed improvements in response inhibition and increased recruitment of dorsal anterior cingulate cortex, medial prefrontal cortex, and right anterior insula during negative valence processing. Our findings highlight the importance of active control in MT research, indicate unique neural mechanisms for progressive stages of mindfulness training, and suggest that optimal application of MT may differ depending on context, contrary to a one-size-fits-all approach.

  4. Music Training Enhances Rapid Neural Plasticity of N1 and P2 Source Activation for Unattended Sounds

    PubMed Central

    Seppänen, Miia; Hämäläinen, Jarmo; Pesonen, Anu-Katriina; Tervaniemi, Mari

    2012-01-01

    Neurocognitive studies have demonstrated that long-term music training enhances the processing of unattended sounds. It is not clear, however, whether music training also modulates rapid (within tens of minutes) neural plasticity for sound encoding. To study this phenomenon, we examined whether adult musicians display enhanced rapid neural plasticity compared to non-musicians. More specifically, we compared the modulation of P1, N1, and P2 responses to standard sounds between four unattended passive blocks. Among the standard sounds, infrequently presented deviant sounds were presented (the so-called oddball paradigm). In the middle of the experiment (after two blocks), an active task was presented. Source analysis for event-related potentials (ERPs) showed that N1 and P2 source activation was selectively decreased in musicians after 15 min of passive exposure to sounds and that P2 source activation was found to be re-enhanced after the active task in musicians. Additionally, ERP analysis revealed that in both musicians and non-musicians, P2 ERP amplitude was enhanced after 15 min of passive exposure but only at the frontal electrodes. Furthermore, in musicians, the N1 ERP was enhanced after the active discrimination task but only at the parietal electrodes. Musical training modulates the rapid neural plasticity reflected in N1 and P2 source activation for unattended regular standard sounds. Enhanced rapid plasticity of N1 and P2 is likely to reflect faster auditory perceptual learning in musicians. PMID:22435057

  5. Self-organization of feed-forward structure and entrainment in excitatory neural networks with spike-timing-dependent plasticity

    NASA Astrophysics Data System (ADS)

    Takahashi, Yuko K.; Kori, Hiroshi; Masuda, Naoki

    2009-05-01

    Spike-timing dependent plasticity (STDP) is an organizing principle of biological neural networks. While synchronous firing of neurons is considered to be an important functional block in the brain, how STDP shapes neural networks possibly toward synchrony is not entirely clear. We examine relations between STDP and synchronous firing in spontaneously firing neural populations. Using coupled heterogeneous phase oscillators placed on initial networks, we show numerically that STDP prunes some synapses and promotes formation of a feedforward network. Eventually a pacemaker, which is the neuron with the fastest inherent frequency in our numerical simulations, emerges at the root of the feedforward network. In each oscillatory cycle, a packet of neural activity is propagated from the pacemaker to downstream neurons along layers of the feedforward network. This event occurs above a clear-cut threshold value of the initial synaptic weight. Below the threshold, neurons are self-organized into separate clusters each of which is a feedforward network.

  6. Sex Differences in Fetal Habituation

    ERIC Educational Resources Information Center

    Hepper, Peter G.; Dornan, James C.; Lynch, Catherine

    2012-01-01

    There is some evidence for sex differences in habituation in the human fetus, but it is unknown whether this is due to differences in central processing (habituation) or in more peripheral processes, sensory or motor, involved in the response. This study examined whether the sex of the fetus influenced auditory habituation at 33 weeks of…

  7. Anterior thalamic nuclei lesions in rats disrupt markers of neural plasticity in distal limbic brain regions

    PubMed Central

    Dumont, J.R.; Amin, E.; Poirier, G.L.; Albasser, M.M.; Aggleton, J.P.

    2012-01-01

    In two related experiments, neurotoxic lesions were placed in the anterior thalamic nuclei of adult rats. The rats were then trained on behavioral tasks, immediately followed by the immunohistochemical measurement of molecules linked to neural plasticity. These measurements were made in limbic sites including the retrosplenial cortex, the hippocampal formation, and parahippocampal areas. In Experiment 1, rats with unilateral anterior thalamic lesions explored either novel or familiar objects prior to analysis of the immediate-early gene zif268. The lesions reduced zif268 activity in the granular retrosplenial cortex and postsubiculum. Exploring novel objects resulted in local changes of hippocampal zif268, but this change was not moderated by anterior thalamic lesions. In Experiment 2, rats that had received either bilateral anterior thalamic lesions or control surgeries were exposed to novel room cues while running in the arms of a radial maze. In addition to zif268, measurements of c-AMP response element binding protein (CREB), phosphorylated CREB (pCREB), and growth associated protein43 (GAP-43) were made. As before, anterior thalamic lesions reduced zif268 in retrosplenial cortex and postsubiculum, but there were also reductions of pCREB in granular retrosplenial cortex. Again, the hippocampus did not show lesion-induced changes in zif268, but there were differential effects on CREB and pCREB consistent with reduced levels of hippocampal CREB phosphorylation following anterior thalamic damage. No changes in GAP-43 were detected. The results not only point to changes in several limbic sites (retrosplenial cortex and hippocampus) following anterior thalamic damage, but also indicate that these changes include decreased levels of pCREB. As pCREB is required for neuronal plasticity, partly because of its regulation of immediate early-gene expression, the present findings reinforce the concept of an ‘extended hippocampal system’ in which hippocampal function is

  8. Downstream effect of ramping neural activity through synapses with short-term plasticity

    PubMed Central

    Wei, Wei; Wang, Xiao-Jing

    2016-01-01

    Ramping neuronal activity has been observed in multiple cortical areas correlated with evidence accumulation processes or timing. In this work we investigate the downstream effect of ramping neuronal activity through synapses that display short-term facilitation (STF) or depression (STD). We obtain an analytical result for a synapse driven by deterministic linear ramping input that exhibits pure STF or STD, and investigate the general case when both STF and STD exist numerically. In neural circuits, the ramping inputs usually have strong fluctuation and each downstream neuron receives converging inputs from many presynaptic neurons. We show that the analytical deterministic solution gives an accurate description of the averaging synaptic activation that a postsynaptic neuron receives in a neural circuit, even when the fluctuation in ramping input is strong. Therefore our work provides insights on the impact of ramping neuronal activity on downstream neurons through synapses displaying short-term plasticity. Specifically, activation of a synapse with STF shows a sublinear increase with time and is insensitive to the slopes of ramping inputs during the initial period, followed by a linear ramping similar to a synapse without STF. Activation of a synapse with STD, on the other hand, develops a local maximum before reaching a steady state, which is independent of the slope of ramping input. For a synapse displaying both STF and STD, increase of the depression time constant from a value much smaller than the facilitation time constant τF to a value much larger than τF leads to a transition from facilitation domination to depression domination. By utilizing STD in the corticostriatal synapses, our work provides an understanding of the saturation of striatal activity as observed for monkeys performing evidence accumulation. Our work also predicts that in the fixed duration version of motion discrimination tasks the stationary state of neuronal activity downstream to the

  9. Modeling activity-dependent plasticity in BCM spiking neural networks with application to human behavior recognition.

    PubMed

    Meng, Yan; Jin, Yaochu; Yin, Jun

    2011-12-01

    Spiking neural networks (SNNs) are considered to be computationally more powerful than conventional NNs. However, the capability of SNNs in solving complex real-world problems remains to be demonstrated. In this paper, we propose a substantial extension of the Bienenstock, Cooper, and Munro (BCM) SNN model, in which the plasticity parameters are regulated by a gene regulatory network (GRN). Meanwhile, the dynamics of the GRN is dependent on the activation levels of the BCM neurons. We term the whole model "GRN-BCM." To demonstrate its computational power, we first compare the GRN-BCM with a standard BCM, a hidden Markov model, and a reservoir computing model on a complex time series classification problem. Simulation results indicate that the GRN-BCM significantly outperforms the compared models. The GRN-BCM is then applied to two widely used datasets for human behavior recognition. Comparative results on the two datasets suggest that the GRN-BCM is very promising for human behavior recognition, although the current experiments are still limited to the scenarios in which only one object is moving in the considered video sequences.

  10. Training-Specific Neural Plasticity in Spinal Reflexes after Incomplete Spinal Cord Injury

    PubMed Central

    Patrick, Susan K.; Roy, Francois D.; Gorassini, Monica A.

    2016-01-01

    The neural plasticity of spinal reflexes after two contrasting forms of walking training was determined in individuals with chronic, motor-incomplete spinal cord injury (SCI). Endurance Training involved treadmill walking for as long as possible, and Precision Training involved walking precisely over obstacles and onto targets overground. Twenty participants started either Endurance or Precision Training for 2 months and then crossed over after a 2-month rest period to the other form of training for 2 months. Measures were taken before and after each phase of training and rest. The cutaneomuscular reflex (CMR) during walking was evoked in the soleus (SOL) and tibialis anterior muscles by stimulating the posterior tibial nerve at the ankle. Clonus was estimated from the EMG power in the SOL during unperturbed walking. The inhibitory component of the SOL CMR was enhanced after Endurance but not Precision Training. Clonus did not change after either form of training. Participants with lower reflex excitability tended to be better walkers (i.e., faster walking speeds) prior to training, and the reduction in clonus was significantly correlated with the improvement in walking speed and distance. Thus, reflex excitability responded in a training-specific way, with the reduction in reflex excitability related to improvements in walking function. Trial registration number is NCT01765153. PMID:27725887

  11. Habituation of attentional networks during emotion processing.

    PubMed

    Feinstein, Justin S; Goldin, Philippe R; Stein, Murray B; Brown, Gregory G; Paulus, Martin P

    2002-07-19

    Dysfunctional emotion processing is a key aspect of many neuropsychiatric disorders. This dysfunction may be due to an abnormal magnitude of neural substrate activation during emotion processing or due to an altered time course of the neural substrate response. To better understand the temporal characteristics of the neural substrate activation underlying implicit emotion processing, nine healthy female controls were repeatedly exposed to pictures of affective faces while performing a gender identification task in an fMRI. As the salience of the stimuli decreased with repeated exposure, brain areas implicated in a right hemispheric spatial attention network (including the posterior parietal cortex (BA 40) and the frontal eye fields (BA 6)) habituated while brain areas lateralized to the left hemisphere (including the angular gyrus (BA 39), posterior superior temporal gyrus (BA 39) and insula (BA 13)) sensitized. These results provide strong evidence that the time course of activation is a critical component when assessing the function of neural substrates underlying emotion processing (specifically whether habituation is altered) in neuro-psychiatric patients. PMID:12151781

  12. Structure and plasticity potential of neural networks in the cerebral cortex

    NASA Astrophysics Data System (ADS)

    Fares, Tarec Edmond

    In this thesis, we first described a theoretical framework for the analysis of spine remodeling plasticity. We provided a quantitative description of two models of spine remodeling in which the presence of a bouton is either required or not for the formation of a new synapse. We derived expressions for the density of potential synapses in the neuropil, the connectivity fraction, which is the ratio of actual to potential synapses, and the number of structurally different circuits attainable with spine remodeling. We calculated these parameters in mouse occipital cortex, rat CA1, monkey V1, and human temporal cortex. We found that on average a dendritic spine can choose among 4-7 potential targets in rodents and 10-20 potential targets in primates. The neuropil's potential for structural circuit remodeling is highest in rat CA1 (7.1-8.6 bits/mum3) and lowest in monkey V1 (1.3-1.5 bits/mum 3 We next studied the role neuron morphology plays in defining synaptic connectivity. As previously stated it is clear that only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, ). We also evaluated the lower bound of neuron selectivity in the choice of synaptic partners. Post-synaptic excitatory neurons in rodents make synaptic contacts with more than 21-30% of pre-synaptic axons encountered with new spine growth. Primate neurons appear to be more selective, making synaptic connections with more than 7-15% of encountered axons. We next studied the role neuron morphology plays in defining synaptic connectivity. As previously stated it is clear that only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, such axo-dendritic oppositions, or potential synapses, must be bridged by dendritic spines to form synaptic connections. To explore the rules by which synaptic connections are formed within

  13. Examining neural plasticity and cognitive benefit through the unique lens of musical training.

    PubMed

    Moreno, Sylvain; Bidelman, Gavin M

    2014-02-01

    Training programs aimed to alleviate or improve auditory-cognitive abilities have either experienced mixed success or remain to be fully validated. The limited benefits of such regimens are largely attributable to our weak understanding of (i) how (and which) interventions provide the most robust and long lasting improvements to cognitive and perceptual abilities and (ii) how the neural mechanisms which underlie such abilities are positively modified by certain activities and experience. Recent studies indicate that music training provides robust, long-lasting biological benefits to auditory function. Importantly, the behavioral advantages conferred by musical experience extend beyond simple enhancements to perceptual abilities and even impact non-auditory functions necessary for higher-order aspects of cognition (e.g., working memory, intelligence). Collectively, preliminary findings indicate that alternative forms of arts engagement (e.g., visual arts training) may not yield such widespread enhancements, suggesting that music expertise uniquely taps and refines a hierarchy of brain networks subserving a variety of auditory as well as domain-general cognitive mechanisms. We infer that transfer from specific music experience to broad cognitive benefit might be mediated by the degree to which a listener's musical training tunes lower- (e.g., perceptual) and higher-order executive functions, and the coordination between these processes. Ultimately, understanding the broad impact of music on the brain will not only provide a more holistic picture of auditory processing and plasticity, but may help inform and tailor remediation and training programs designed to improve perceptual and cognitive benefits in human listeners.

  14. Examining neural plasticity and cognitive benefit through the unique lens of musical training.

    PubMed

    Moreno, Sylvain; Bidelman, Gavin M

    2014-02-01

    Training programs aimed to alleviate or improve auditory-cognitive abilities have either experienced mixed success or remain to be fully validated. The limited benefits of such regimens are largely attributable to our weak understanding of (i) how (and which) interventions provide the most robust and long lasting improvements to cognitive and perceptual abilities and (ii) how the neural mechanisms which underlie such abilities are positively modified by certain activities and experience. Recent studies indicate that music training provides robust, long-lasting biological benefits to auditory function. Importantly, the behavioral advantages conferred by musical experience extend beyond simple enhancements to perceptual abilities and even impact non-auditory functions necessary for higher-order aspects of cognition (e.g., working memory, intelligence). Collectively, preliminary findings indicate that alternative forms of arts engagement (e.g., visual arts training) may not yield such widespread enhancements, suggesting that music expertise uniquely taps and refines a hierarchy of brain networks subserving a variety of auditory as well as domain-general cognitive mechanisms. We infer that transfer from specific music experience to broad cognitive benefit might be mediated by the degree to which a listener's musical training tunes lower- (e.g., perceptual) and higher-order executive functions, and the coordination between these processes. Ultimately, understanding the broad impact of music on the brain will not only provide a more holistic picture of auditory processing and plasticity, but may help inform and tailor remediation and training programs designed to improve perceptual and cognitive benefits in human listeners. PMID:24079993

  15. Treadmill step training promotes spinal cord neural plasticity after incomplete spinal cord injury

    PubMed Central

    Sun, Tiansheng; Ye, Chaoqun; Wu, Jun; Zhang, Zhicheng; Cai, Yanhua; Yue, Feng

    2013-01-01

    A large body of evidence shows that spinal circuits are significantly affected by training, and that intrinsic circuits that drive locomotor tasks are located in lumbosacral spinal segments in rats with complete spinal cord transection. However, after incomplete lesions, the effect of treadmill training has been debated, which is likely because of the difficulty of separating spontaneous stepping from specific training-induced effects. In this study, rats with moderate spinal cord contusion were jected to either step training on a treadmill or used in the model (control) group. The treadmill training began at day 7 post-injury and lasted 20 ± 10 minutes per day, 5 days per week for 10 weeks. The speed of the treadmill was set to 3 m/min and was increased on a daily basis according to the tolerance of each rat. After 3 weeks of step training, the step training group exhibited a sig-nificantly greater improvement in the Basso, Beattie and Bresnahan score than the model group. The expression of growth-associated protein-43 in the spinal cord lesion site and the number of tyrosine hydroxylase-positive ventral neurons in the second lumbar spinal segment were greater in the step training group than in the model group at 11 weeks post-injury, while the levels of brain-derived neurotrophic factor protein in the spinal cord lesion site showed no difference between the two groups. These results suggest that treadmill training significantly improves functional re-covery and neural plasticity after incomplete spinal cord injury. PMID:25206564

  16. Transfer functions for protein signal transduction: application to a model of striatal neural plasticity.

    PubMed

    Scheler, Gabriele

    2013-01-01

    We present a novel formulation for biochemical reaction networks in the context of protein signal transduction. The model consists of input-output transfer functions, which are derived from differential equations, using stable equilibria. We select a set of "source" species, which are interpreted as input signals. Signals are transmitted to all other species in the system (the "target" species) with a specific delay and with a specific transmission strength. The delay is computed as the maximal reaction time until a stable equilibrium for the target species is reached, in the context of all other reactions in the system. The transmission strength is the concentration change of the target species. The computed input-output transfer functions can be stored in a matrix, fitted with parameters, and even recalled to build dynamical models on the basis of state changes. By separating the temporal and the magnitudinal domain we can greatly simplify the computational model, circumventing typical problems of complex dynamical systems. The transfer function transformation of biochemical reaction systems can be applied to mass-action kinetic models of signal transduction. The paper shows that this approach yields significant novel insights while remaining a fully testable and executable dynamical model for signal transduction. In particular we can deconstruct the complex system into local transfer functions between individual species. As an example, we examine modularity and signal integration using a published model of striatal neural plasticity. The modularizations that emerge correspond to a known biological distinction between calcium-dependent and cAMP-dependent pathways. Remarkably, we found that overall interconnectedness depends on the magnitude of inputs, with higher connectivity at low input concentrations and significant modularization at moderate to high input concentrations. This general result, which directly follows from the properties of individual transfer

  17. What Habituates in Infant Visual Habituation? A Psychophysiological Analysis

    ERIC Educational Resources Information Center

    Colombo, John; Shaddy, D. Jill; Anderson, Christa J.; Gibson, Linzi J.; Blaga, Otilia M.; Kannass, Kathleen N.

    2010-01-01

    Despite the use of visual habituation over the past half century, relatively little is known about its underlying processes. We analyzed heart rate (HR) taken simultaneous with looking during infant-controlled habituation sessions collected longitudinally at 4, 6, and 8 months of age with the goal of examining how HR and HR-defined phases of…

  18. Protein kinase C substrate phosphorylation in relation to neural growth and synaptic plasticity: a common molecular mechanism underlying multiple neural functions

    SciTech Connect

    Nelson, R.B.

    1987-01-01

    In these studies, we addressed the issues of: (1) whether neural protein kinase C (PKC) substrates might be altered in phosphorylation following induction of long-term potentiation (LTP); (2) whether PKC substrate phosphorylation might be specifically related to a model of neural plasticity other than LTP; and (3) whether the PKC substrates implicated in adult synaptic plasticity might be present in axonal growth cones given reports that high concentrations of PKC are found in these structures. Using quantitative analysis of multiple two-dimensional gels, we found that the two major substrates of exogenous purified PKC in adult hippocampal homogenate are both directly correlated to persistence of LTP. In rhesus monkey cerebral cortex, the proteins corresponding to protein F1 and 80k displayed topographical gradients in /sup 32/P-incorporation along the occipitotemporal visual processing pathway. The phosphorylation of both proteins was 11- and 14-fold higher, respectively, in temporal regions of this pathway implicated in the storage of visual representations, than in occipital regions, which do not appear to directly participate in visual memory functions.

  19. Diverse synaptic plasticity mechanisms orchestrated to form and retrieve memories in spiking neural networks

    PubMed Central

    Zenke, Friedemann; Agnes, Everton J.; Gerstner, Wulfram

    2015-01-01

    Synaptic plasticity, the putative basis of learning and memory formation, manifests in various forms and across different timescales. Here we show that the interaction of Hebbian homosynaptic plasticity with rapid non-Hebbian heterosynaptic plasticity is, when complemented with slower homeostatic changes and consolidation, sufficient for assembly formation and memory recall in a spiking recurrent network model of excitatory and inhibitory neurons. In the model, assemblies were formed during repeated sensory stimulation and characterized by strong recurrent excitatory connections. Even days after formation, and despite ongoing network activity and synaptic plasticity, memories could be recalled through selective delay activity following the brief stimulation of a subset of assembly neurons. Blocking any component of plasticity prevented stable functioning as a memory network. Our modelling results suggest that the diversity of plasticity phenomena in the brain is orchestrated towards achieving common functional goals. PMID:25897632

  20. Multiple levels of impaired neural plasticity and cellular resilience in bipolar disorder: Developing treatments using an integrated translational approach

    PubMed Central

    Machado-Vieira, Rodrigo; Soeiro-De-Souza, Marcio G.; Richards, Erica M.; Teixeira, Antonio L.; Zarate, Carlos A.

    2014-01-01

    Objectives This paper reviews the neurobiology of bipolar disorder (BD), particularly findings associated with impaired cellular resilience and plasticity. Methods PubMed/Medline articles and book chapters published over the last 20 years were identified using the following keyword combinations: BD, calcium, cytokines, endoplasmic reticulum (ER), genetics, glucocorticoids, glutamate, imaging, ketamine, lithium, mania, mitochondria, neuroplasticity, neuroprotection, neurotrophic, oxidative stress, plasticity, resilience, and valproate. Results BD is associated with impaired cellular resilience and synaptic dysfunction at multiple levels, associated with impaired cellular resilience and plasticity. These findings were partially prevented or even reversed with the use of mood stabilizers, but longitudinal studies associated with clinical outcome remain scarce. Conclusions Evidence consistently suggests that BD involves impaired neural plasticity and cellular resilience at multiple levels. This includes the genetic and intra- and intercellular signalling levels, their impact on brain structure and function, as well as the final translation into behaviour/cognitive changes. Future studies are expected to adopt integrated translational approaches using a variety of methods (e.g., microarray approaches, neuroimaging, genetics, electrophysiology, and the new generation of –omics techniques). These studies will likely focus on more precise diagnoses and a personalized medicine paradigm in order to develop better treatments for those who need them most. PMID:23998912

  1. A Peptide Mimetic Targeting Trans-Homophilic NCAM Binding Sites Promotes Spatial Learning and Neural Plasticity in the Hippocampus

    PubMed Central

    Kohler, Lene B.; Fantin, Martina; Jennings, Alistair; Venero, Cesar; Popov, Victor; Rusakov, Dmitri; Stewart, Michael G.; Bock, Elisabeth; Berezin, Vladimir; Sandi, Carmen

    2011-01-01

    The key roles played by the neural cell adhesion molecule (NCAM) in plasticity and cognition underscore this membrane protein as a relevant target to develop cognitive-enhancing drugs. However, NCAM is a structurally and functionally complex molecule with multiple domains engaged in a variety of actions, which raise the question as to which NCAM fragment should be targeted. Synthetic NCAM mimetic peptides that mimic NCAM sequences relevant to specific interactions allow identification of the most promising targets within NCAM. Recently, a decapeptide ligand of NCAM—plannexin, which mimics a homophilic trans-binding site in Ig2 and binds to Ig3—was developed as a tool for studying NCAM's trans-interactions. In this study, we investigated plannexin's ability to affect neural plasticity and memory formation. We found that plannexin facilitates neurite outgrowth in primary hippocampal neuronal cultures and improves spatial learning in rats, both under basal conditions and under conditions involving a deficit in a key plasticity-promoting posttranslational modification of NCAM, its polysialylation. We also found that plannexin enhances excitatory synaptic transmission in hippocampal area CA1, where it also increases the number of mushroom spines and the synaptic expression of the AMPAR subunits GluA1 and GluA2. Altogether, these findings provide compelling evidence that plannexin is an important facilitator of synaptic functional, structural and molecular plasticity in the hippocampal CA1 region, highlighting the fragment in NCAM's Ig3 module where plannexin binds as a novel target for the development of cognition-enhancing drugs. PMID:21887252

  2. Neural bases of peri-hand space plasticity through tool-use: insights from a combined computational-experimental approach.

    PubMed

    Magosso, Elisa; Ursino, Mauro; di Pellegrino, Giuseppe; Làdavas, Elisabetta; Serino, Andrea

    2010-02-01

    Visual peripersonal space (i.e., the space immediately surrounding the body) is represented by multimodal neurons integrating tactile stimuli applied on a body part with visual stimuli delivered near the same body part, e.g., the hand. Tool use may modify the boundaries of the peri-hand area, where vision and touch are integrated. The neural mechanisms underlying such plasticity have not been yet identified. To this aim, neural network modelling may be integrated with experimental research. In the present work, we pursued two main objectives: (i) using an artificial neural network to postulate some physiological mechanisms for peri-hand space plasticity in order to account for in-vivo data; (ii) validating model predictions with an ad-hoc behavioural experiment on an extinction patient. The model assumes that the modification of peri-hand space arises from a Hebbian growing of visual synapses converging into the multimodal area, which extends the visual receptive field (RF) of the peripersonal bimodal neurons. Under this hypothesis, the model is able to interpret and explain controversial results in the current literature, showing how different tool-use tasks during the learning phase result in different re-sizing effects of the peri-hand space. Importantly, the model also implies that, after tool-use, a far visual stimulus acts as a near one, independently of whether the tool is present or absent in the subject's hand. This prediction has been validated by an in-vivo experiment on a right brain-damaged patient suffering from visual-tactile extinction. This study demonstrates how neural network modelling may integrate with experimental studies, by generating new predictions and suggesting novel experiments to investigate cognitive processes.

  3. Neural plasticity in hypocretin neurons: the basis of hypocretinergic regulation of physiological and behavioral functions in animals

    PubMed Central

    Gao, Xiao-Bing; Hermes, Gretchen

    2015-01-01

    The neuronal system that resides in the perifornical and lateral hypothalamus (Pf/LH) and synthesizes the neuropeptide hypocretin/orexin participates in critical brain functions across species from fish to human. The hypocretin system regulates neural activity responsible for daily functions (such as sleep/wake homeostasis, energy balance, appetite, etc.) and long-term behavioral changes (such as reward seeking and addiction, stress response, etc.) in animals. The most recent evidence suggests that the hypocretin system undergoes substantial plastic changes in response to both daily fluctuations (such as food intake and sleep-wake regulation) and long-term changes (such as cocaine seeking) in neuronal activity in the brain. The understanding of these changes in the hypocretin system is essential in addressing the role of the hypocretin system in normal physiological functions and pathological conditions in animals and humans. In this review, the evidence demonstrating that neural plasticity occurs in hypocretin-containing neurons in the Pf/LH will be presented and possible physiological, behavioral, and mental health implications of these findings will be discussed. PMID:26539086

  4. Evolutionarily-conserved role of the NF-kappaB transcription factor in neural plasticity and memory.

    PubMed

    Romano, Arturo; Freudenthal, Ramiro; Merlo, Emiliano; Routtenberg, Aryeh

    2006-09-01

    NF-kappaB is an evolutionarily conserved family of transcription factors (TFs) critically involved in basic cellular mechanisms of the immune response, inflammation, development and apoptosis. In spite of the fact that it is expressed in the central nervous system, particularly in areas involved in memory processing, and is activated by signals such as glutamate and Ca2+, its role in neural plasticity and memory has only recently become apparent. A surprising feature of this molecule is its presence within the synapse. An increasing number of reports have called attention to the role of this TF in processes that require long-term regulation of the synaptic function underlying memory and neural plasticity. Here we review the evidence regarding a dual role for NF-kappaB, as both a signalling molecule after its activation at the synapse and a transcriptional regulator upon reaching the nucleus. The specific role of this signal, as well as the general transcriptional mechanism, in the process of memory formation is discussed. Converging lines of evidence summarized here point to a pivotal role for the NF-kappaB transcription factor as a direct signalling mechanism in the regulation of gene expression involved in long-term memory.

  5. The Frog Vestibular System as a Model for Lesion-Induced Plasticity: Basic Neural Principles and Implications for Posture Control

    PubMed Central

    Lambert, François M.; Straka, Hans

    2011-01-01

    Studies of behavioral consequences after unilateral labyrinthectomy have a long tradition in the quest of determining rules and limitations of the central nervous system (CNS) to exert plastic changes that assist the recuperation from the loss of sensory inputs. Frogs were among the first animal models to illustrate general principles of regenerative capacity and reorganizational neural flexibility after a vestibular lesion. The continuous successful use of the latter animals is in part based on the easy access and identifiability of nerve branches to inner ear organs for surgical intervention, the possibility to employ whole brain preparations for in vitro studies and the limited degree of freedom of postural reflexes for quantification of behavioral impairments and subsequent improvements. Major discoveries that increased the knowledge of post-lesional reactive mechanisms in the CNS include alterations in vestibular commissural signal processing and activation of cooperative changes in excitatory and inhibitory inputs to disfacilitated neurons. Moreover, the observed increase of synaptic efficacy in propriospinal circuits illustrates the importance of limb proprioceptive inputs for postural recovery. Accumulated evidence suggests that the lesion-induced neural plasticity is not a goal-directed process that aims toward a meaningful restoration of vestibular reflexes but rather attempts a survival of those neurons that have lost their excitatory inputs. Accordingly, the reaction mechanism causes an improvement of some components but also a deterioration of other aspects as seen by spatio-temporally inappropriate vestibulo-motor responses, similar to the consequences of plasticity processes in various sensory systems and species. The generality of the findings indicate that frogs continue to form a highly amenable vertebrate model system for exploring molecular and physiological events during cellular and network reorganization after a loss of vestibular function

  6. Helping the Habitually Late Student.

    ERIC Educational Resources Information Center

    Bergman, Jerry

    1978-01-01

    The author gives three major reasons for a student being habitually late to class: resistance, disorganization, or unavoidable schedule conflicts. He makes specific suggestions to teachers for dealing with the disorganized and resistant latecomers. (SJL)

  7. Modification of tenascin-R expression following unilateral labyrinthectomy in rats indicates its possible role in neural plasticity of the vestibular neural circuit.

    PubMed

    Gaal, Botond; Jóhannesson, Einar Örn; Dattani, Amit; Magyar, Agnes; Wéber, Ildikó; Matesz, Clara

    2015-09-01

    We have previously found that unilateral labyrinthectomy is accompanied by modification of hyaluronan and chondroitin sulfate proteoglycan staining in the lateral vestibular nucleus of rats and the time course of subsequent reorganization of extracellular matrix assembly correlates to the restoration of impaired vestibular function. The tenascin-R has repelling effect on pathfinding during axonal growth/regrowth, and thus inhibits neural circuit repair. By using immunohistochemical method, we studied the modification of tenascin-R expression in the superior, medial, lateral, and descending vestibular nuclei of the rat following unilateral labyrinthectomy. On postoperative day 1, tenascin-R reaction in the perineuronal nets disappeared on the side of labyrinthectomy in the superior, lateral, medial, and rostral part of the descending vestibular nuclei. On survival day 3, the staining intensity of tenascin-R reaction in perineuronal nets recovered on the operated side of the medial vestibular nucleus, whereas it was restored by the time of postoperative day 7 in the superior, lateral and rostral part of the descending vestibular nuclei. The staining intensity of tenascin-R reaction remained unchanged in the caudal part of the descending vestibular nucleus bilaterally. Regional differences in the modification of tenascin-R expression presented here may be associated with different roles of individual vestibular nuclei in the compensatory processes. The decreased expression of the tenascin-R may suggest the extracellular facilitation of plastic modifications in the vestibular neural circuit after lesion of the labyrinthine receptors.

  8. Modification of tenascin-R expression following unilateral labyrinthectomy in rats indicates its possible role in neural plasticity of the vestibular neural circuit

    PubMed Central

    Gaal, Botond; Jóhannesson, Einar Örn; Dattani, Amit; Magyar, Agnes; Wéber, Ildikó; Matesz, Clara

    2015-01-01

    We have previously found that unilateral labyrinthectomy is accompanied by modification of hyaluronan and chondroitin sulfate proteoglycan staining in the lateral vestibular nucleus of rats and the time course of subsequent reorganization of extracellular matrix assembly correlates to the restoration of impaired vestibular function. The tenascin-R has repelling effect on pathfinding during axonal growth/regrowth, and thus inhibits neural circuit repair. By using immunohistochemical method, we studied the modification of tenascin-R expression in the superior, medial, lateral, and descending vestibular nuclei of the rat following unilateral labyrinthectomy. On postoperative day 1, tenascin-R reaction in the perineuronal nets disappeared on the side of labyrinthectomy in the superior, lateral, medial, and rostral part of the descending vestibular nuclei. On survival day 3, the staining intensity of tenascin-R reaction in perineuronal nets recovered on the operated side of the medial vestibular nucleus, whereas it was restored by the time of postoperative day 7 in the superior, lateral and rostral part of the descending vestibular nuclei. The staining intensity of tenascin-R reaction remained unchanged in the caudal part of the descending vestibular nucleus bilaterally. Regional differences in the modification of tenascin-R expression presented here may be associated with different roles of individual vestibular nuclei in the compensatory processes. The decreased expression of the tenascin-R may suggest the extracellular facilitation of plastic modifications in the vestibular neural circuit after lesion of the labyrinthine receptors. PMID:26604908

  9. Discrimination of poly(vinyl chloride) samples with different plasticizers and prediction of plasticizer contents in poly(vinyl chloride) using near-infrared spectroscopy and neural-network analysis.

    PubMed

    Saeki, Kazumitsu; Funatsu, Kimito; Tanabe, Kazutoshi

    2003-02-01

    In the recycling of poly(vinyl chloride) (PVC), it is required to discriminate every plasticizer for quality control. For this purpose, the near-infrared spectra were measured for 41 kinds of PVC samples with different plasticizers (DINP, DOP, DOA, TOTM and Polyester) and different plasticizer contents (0-49%). A neural-network analysis was applied to the near-infrared spectra pretreated by second-derivative processing. They were discriminated from one another. The neural-network analysis also allowed us to propose a calibration model which predicts the contents of plasticizers in PVC. The correlation coefficient (R) and the root-mean-square error of prediction (RMSEP) for the DINP calibration model were found to be 0.999 and 0.41 wt%, respectively. In comparison, a partial least-squares regression analysis was carried out. The R and RMSEP of the DINP calibration model were calculated to be 0.993 and 1.27 wt%, respectively. It is found that a near-infrared spectra measurement combined with a neural-network analysis is useful for plastic recycling.

  10. Habituation and 1/f Noise

    NASA Astrophysics Data System (ADS)

    West, Bruce; Grigolini, Paolo

    2010-03-01

    We present a model to explain the psychophysical phenomena of habituation using methods from non-equilibrium statistical physics and complex network theory. Habituation is a ubiquitous and extremely simple from of learning through which animals, including humans; learn to disregard stimuli that are no longer novel, thereby allowing them to attend to new stimuli.Herein we present a statistical habituation model (SHM) based on a generalization of linear response theory and discrete events using renewal theory. The SHM introduces a theory of the effective synaptic weight connecting two neuron networks, with the synaptic weight being described by a time series with inverse power-law statistics. The statistics determine the distribution of time intervals between events, which in a complex neuronal network leads to neuronal avalanches, see e.g., Beggs and Plenz (J. Neurosci 23, 11167, 2003). The SHM establishes that the fundamental mechanism producing habituation in its myriad of forms is the 1/f-nose that is generically produced in individual neurons and in complex neuronal networks. Both simple harmonic and more complicated stimuli are shown to habituate (decay) as inverse power laws with indices determined by the power-law index of the effective synaptic statistical distribution. This is the first theory that directly relates the psychophysical phenomenon of habituation to the dynamics of the brain.

  11. Stable learning of functional maps in self-organizing spiking neural networks with continuous synaptic plasticity

    PubMed Central

    Srinivasa, Narayan; Jiang, Qin

    2013-01-01

    This study describes a spiking model that self-organizes for stable formation and maintenance of orientation and ocular dominance maps in the visual cortex (V1). This self-organization process simulates three development phases: an early experience-independent phase, a late experience-independent phase and a subsequent refinement phase during which experience acts to shape the map properties. The ocular dominance maps that emerge accommodate the two sets of monocular inputs that arise from the lateral geniculate nucleus (LGN) to layer 4 of V1. The orientation selectivity maps that emerge feature well-developed iso-orientation domains and fractures. During the last two phases of development the orientation preferences at some locations appear to rotate continuously through ±180° along circular paths and referred to as pinwheel-like patterns but without any corresponding point discontinuities in the orientation gradient maps. The formation of these functional maps is driven by balanced excitatory and inhibitory currents that are established via synaptic plasticity based on spike timing for both excitatory and inhibitory synapses. The stability and maintenance of the formed maps with continuous synaptic plasticity is enabled by homeostasis caused by inhibitory plasticity. However, a prolonged exposure to repeated stimuli does alter the formed maps over time due to plasticity. The results from this study suggest that continuous synaptic plasticity in both excitatory neurons and interneurons could play a critical role in the formation, stability, and maintenance of functional maps in the cortex. PMID:23450808

  12. Sensory habituation of auditory receptor neurons: implications for sound localization.

    PubMed

    Givois, V; Pollack, G S

    2000-09-01

    Auditory receptor neurons exhibit sensory habituation; their responses decline with repeated stimulation. We studied the effects of sensory habituation on the neural encoding of sound localization cues using crickets as a model system. In crickets, Teleogryllus oceanicus, sound localization is based on binaural comparison of stimulus intensity. There are two potential codes at the receptor-neuron level for interaural intensity difference: interaural difference in response strength, i.e. spike rate and/or count, and interaural difference in response latency. These are affected differently by sensory habituation. When crickets are stimulated with cricket-song-like trains of sound pulses, response strength declines for successive pulses in the train, and the decrease becomes more pronounced as the stimulus intensity increases. Response decrement is thus greater for receptors serving the ear ipsilateral to the sound source, where intensity is higher, resulting in a decrease in the interaural difference in response strength. Sensory habituation also affects response latency, which increases for responses to successive sound pulses in the stimulus train. The change in latency is independent of intensity, and thus is similar for receptors serving both ears. As a result, interaural latency difference is unaffected by sensory habituation and may be a more reliable cue for sound localization.

  13. Learning to Perceive Structure from Motion and Neural Plasticity in Patients with Alzheimer's Disease

    ERIC Educational Resources Information Center

    Kim, Nam-Gyoon; Park, Jong-Hee

    2010-01-01

    Recent research has demonstrated that Alzheimer's disease (AD) affects the visual sensory pathways, producing a variety of visual deficits, including the capacity to perceive structure-from-motion (SFM). Because the sensory areas of the adult brain are known to retain a large degree of plasticity, the present study was conducted to explore whether…

  14. Dissociation of Neural Networks for Predisposition and for Training-Related Plasticity in Auditory-Motor Learning.

    PubMed

    Herholz, Sibylle C; Coffey, Emily B J; Pantev, Christo; Zatorre, Robert J

    2016-07-01

    Skill learning results in changes to brain function, but at the same time individuals strongly differ in their abilities to learn specific skills. Using a 6-week piano-training protocol and pre- and post-fMRI of melody perception and imagery in adults, we dissociate learning-related patterns of neural activity from pre-training activity that predicts learning rates. Fronto-parietal and cerebellar areas related to storage of newly learned auditory-motor associations increased their response following training; in contrast, pre-training activity in areas related to stimulus encoding and motor control, including right auditory cortex, hippocampus, and caudate nuclei, was predictive of subsequent learning rate. We discuss the implications of these results for models of perceptual and of motor learning. These findings highlight the importance of considering individual predisposition in plasticity research and applications. PMID:26139842

  15. Reversible Inactivation of the Auditory Thalamus Disrupts HPA Axis Habituation to Repeated Loud Noise Stress Exposures

    PubMed Central

    Day, Heidi E.W.; Masini, Cher V.; Campeau, Serge

    2009-01-01

    Although habituation to stress is a widely observed adaptive mechanism in response to repeated homotypic challenge exposure, its brain location and mechanism of plasticity remains elusive. And while habituation-related plasticity has been suggested to take place in central limbic regions, recent evidence suggests that sensory sites may provide the underlying substrate for this function. For instance, several brainstem, midbrain, thalamic, and/or cortical auditory processing areas, among others, could support habituation-related plasticity to repeated loud noise exposures. In the present study, the auditory thalamus was tested for its putative role in habituation to repeated loud noise exposures, in rats. The auditory thalamus was inactivated reversibly by muscimol injections during repeated loud noise exposures to determine if brainstem or midbrain auditory nuclei would be sufficient to support habituation to this specific stressor, as measured during an additional and drug-free loud noise exposure test. Our results indicate that auditory thalamic inactivation by muscimol disrupts acute HPA axis response specifically to loud noise. Importantly, habituation to repeated loud noise exposures was also prevented by reversible auditory thalamic inactivation, suggesting that this form of plasticity is likely mediated at, or in targets of, the auditory thalamus. PMID:19379718

  16. Cognitive and neural plasticity in older adults' prospective memory following training with the Virtual Week computer game.

    PubMed

    Rose, Nathan S; Rendell, Peter G; Hering, Alexandra; Kliegel, Matthias; Bidelman, Gavin M; Craik, Fergus I M

    2015-01-01

    Prospective memory (PM) - the ability to remember and successfully execute our intentions and planned activities - is critical for functional independence and declines with age, yet few studies have attempted to train PM in older adults. We developed a PM training program using the Virtual Week computer game. Trained participants played the game in 12, 1-h sessions over 1 month. Measures of neuropsychological functions, lab-based PM, event-related potentials (ERPs) during performance on a lab-based PM task, instrumental activities of daily living, and real-world PM were assessed before and after training. Performance was compared to both no-contact and active (music training) control groups. PM on the Virtual Week game dramatically improved following training relative to controls, suggesting PM plasticity is preserved in older adults. Relative to control participants, training did not produce reliable transfer to laboratory-based tasks, but was associated with a reduction of an ERP component (sustained negativity over occipito-parietal cortex) associated with processing PM cues, indicative of more automatic PM retrieval. Most importantly, training produced far transfer to real-world outcomes including improvements in performance on real-world PM and activities of daily living. Real-world gains were not observed in either control group. Our findings demonstrate that short-term training with the Virtual Week game produces cognitive and neural plasticity that may result in real-world benefits to supporting functional independence in older adulthood.

  17. Cognitive and neural plasticity in older adults’ prospective memory following training with the Virtual Week computer game

    PubMed Central

    Rose, Nathan S.; Rendell, Peter G.; Hering, Alexandra; Kliegel, Matthias; Bidelman, Gavin M.; Craik, Fergus I. M.

    2015-01-01

    Prospective memory (PM) – the ability to remember and successfully execute our intentions and planned activities – is critical for functional independence and declines with age, yet few studies have attempted to train PM in older adults. We developed a PM training program using the Virtual Week computer game. Trained participants played the game in 12, 1-h sessions over 1 month. Measures of neuropsychological functions, lab-based PM, event-related potentials (ERPs) during performance on a lab-based PM task, instrumental activities of daily living, and real-world PM were assessed before and after training. Performance was compared to both no-contact and active (music training) control groups. PM on the Virtual Week game dramatically improved following training relative to controls, suggesting PM plasticity is preserved in older adults. Relative to control participants, training did not produce reliable transfer to laboratory-based tasks, but was associated with a reduction of an ERP component (sustained negativity over occipito-parietal cortex) associated with processing PM cues, indicative of more automatic PM retrieval. Most importantly, training produced far transfer to real-world outcomes including improvements in performance on real-world PM and activities of daily living. Real-world gains were not observed in either control group. Our findings demonstrate that short-term training with the Virtual Week game produces cognitive and neural plasticity that may result in real-world benefits to supporting functional independence in older adulthood. PMID:26578936

  18. Rapid homeostatic plasticity of intrinsic excitability in a central pattern generator network stabilizes functional neural network output.

    PubMed

    Ransdell, Joseph L; Nair, Satish S; Schulz, David J

    2012-07-11

    Neurons and networks undergo a process of homeostatic plasticity that stabilizes output by integrating activity levels with network and cellular properties to counter longer-term perturbations. Here we describe a rapid compensatory interaction among a pair of potassium currents, I(A) and I(KCa), that stabilizes both intrinsic excitability and network function in the cardiac ganglion of the crab, Cancer borealis. We determined that mRNA levels in single identified neurons for the channels which encode I(A) and I(KCa) are positively correlated, yet the ionic currents themselves are negatively correlated, across a population of motor neurons. We then determined that these currents are functionally coupled; decreasing levels of either current within a neuron causes a rapid increase in the other. This functional interdependence results in homeostatic stabilization of both the individual neuronal and the network output. Furthermore, these compensatory increases are mechanistically independent, suggesting robustness in the maintenance of neural network output that is critical for survival. Together, we generate a complete model for homeostatic plasticity from mRNA to network output where rapid post-translational compensatory mechanisms acting on a reservoir of channels proteins regulated at the level of gene expression provide homeostatic stabilization of both cellular and network activity. PMID:22787050

  19. Stem cells and neural signalling: the case of neoblast recruitment and plasticity in low dose X-ray treated planarians.

    PubMed

    Rossi, Leonardo; Iacopetti, Paola; Salvetti, Alessandra

    2012-01-01

    Planarians (Platyhelminthes) possess an abundant population of adult stem cells, the neoblasts, capable to give rise to both somatic and germ cells. Although neoblasts share similar morphological features, several pieces of evidence suggest that they constitute a heterogeneous population of cells with distinct ultrastructural and molecular features. We found that in planarians treated with low X-ray doses (5 Gy), only a few neoblasts survive. Among these cells, those located close to the nervous system activate an intense proliferation program and migrate to reconstitute the whole complex neoblast population. This phenomenon is inhibited by the substance P receptor antagonist spantide, and accompanied by the up-regulation of a number of genes implicated in neuronal signalling and plasticity, suggesting that signals of neural origin modulate neoblast proliferation and/or migration. Here, we review these findings and the literature available on the influence of the nervous system on stem cell activity, both in planarians and vertebrates, and we propose 5 Gy-treated planarians as a unique model system to study the influence of neural signalling on stem cell biology.

  20. Refinement and Pattern Formation in Neural Circuits by the Interaction of Traveling Waves with Spike-Timing Dependent Plasticity.

    PubMed

    Bennett, James E M; Bair, Wyeth

    2015-08-01

    Traveling waves in the developing brain are a prominent source of highly correlated spiking activity that may instruct the refinement of neural circuits. A candidate mechanism for mediating such refinement is spike-timing dependent plasticity (STDP), which translates correlated activity patterns into changes in synaptic strength. To assess the potential of these phenomena to build useful structure in developing neural circuits, we examined the interaction of wave activity with STDP rules in simple, biologically plausible models of spiking neurons. We derive an expression for the synaptic strength dynamics showing that, by mapping the time dependence of STDP into spatial interactions, traveling waves can build periodic synaptic connectivity patterns into feedforward circuits with a broad class of experimentally observed STDP rules. The spatial scale of the connectivity patterns increases with wave speed and STDP time constants. We verify these results with simulations and demonstrate their robustness to likely sources of noise. We show how this pattern formation ability, which is analogous to solutions of reaction-diffusion systems that have been widely applied to biological pattern formation, can be harnessed to instruct the refinement of postsynaptic receptive fields. Our results hold for rich, complex wave patterns in two dimensions and over several orders of magnitude in wave speeds and STDP time constants, and they provide predictions that can be tested under existing experimental paradigms. Our model generalizes across brain areas and STDP rules, allowing broad application to the ubiquitous occurrence of traveling waves and to wave-like activity patterns induced by moving stimuli. PMID:26308406

  1. Refinement and Pattern Formation in Neural Circuits by the Interaction of Traveling Waves with Spike-Timing Dependent Plasticity

    PubMed Central

    Bennett, James E. M.; Bair, Wyeth

    2015-01-01

    Traveling waves in the developing brain are a prominent source of highly correlated spiking activity that may instruct the refinement of neural circuits. A candidate mechanism for mediating such refinement is spike-timing dependent plasticity (STDP), which translates correlated activity patterns into changes in synaptic strength. To assess the potential of these phenomena to build useful structure in developing neural circuits, we examined the interaction of wave activity with STDP rules in simple, biologically plausible models of spiking neurons. We derive an expression for the synaptic strength dynamics showing that, by mapping the time dependence of STDP into spatial interactions, traveling waves can build periodic synaptic connectivity patterns into feedforward circuits with a broad class of experimentally observed STDP rules. The spatial scale of the connectivity patterns increases with wave speed and STDP time constants. We verify these results with simulations and demonstrate their robustness to likely sources of noise. We show how this pattern formation ability, which is analogous to solutions of reaction-diffusion systems that have been widely applied to biological pattern formation, can be harnessed to instruct the refinement of postsynaptic receptive fields. Our results hold for rich, complex wave patterns in two dimensions and over several orders of magnitude in wave speeds and STDP time constants, and they provide predictions that can be tested under existing experimental paradigms. Our model generalizes across brain areas and STDP rules, allowing broad application to the ubiquitous occurrence of traveling waves and to wave-like activity patterns induced by moving stimuli. PMID:26308406

  2. Learning, neural plasticity and sensitive periods: implications for language acquisition, music training and transfer across the lifespan.

    PubMed

    White, Erin J; Hutka, Stefanie A; Williams, Lynne J; Moreno, Sylvain

    2013-01-01

    Sensitive periods in human development have often been proposed to explain age-related differences in the attainment of a number of skills, such as a second language (L2) and musical expertise. It is difficult to reconcile the negative consequence this traditional view entails for learning after a sensitive period with our current understanding of the brain's ability for experience-dependent plasticity across the lifespan. What is needed is a better understanding of the mechanisms underlying auditory learning and plasticity at different points in development. Drawing on research in language development and music training, this review examines not only what we learn and when we learn it, but also how learning occurs at different ages. First, we discuss differences in the mechanism of learning and plasticity during and after a sensitive period by examining how language exposure versus training forms language-specific phonetic representations in infants and adult L2 learners, respectively. Second, we examine the impact of musical training that begins at different ages on behavioral and neural indices of auditory and motor processing as well as sensorimotor integration. Third, we examine the extent to which childhood training in one auditory domain can enhance processing in another domain via the transfer of learning between shared neuro-cognitive systems. Specifically, we review evidence for a potential bi-directional transfer of skills between music and language by examining how speaking a tonal language may enhance music processing and, conversely, how early music training can enhance language processing. We conclude with a discussion of the role of attention in auditory learning for learning during and after sensitive periods and outline avenues of future research. PMID:24312022

  3. Learning, neural plasticity and sensitive periods: implications for language acquisition, music training and transfer across the lifespan.

    PubMed

    White, Erin J; Hutka, Stefanie A; Williams, Lynne J; Moreno, Sylvain

    2013-11-20

    Sensitive periods in human development have often been proposed to explain age-related differences in the attainment of a number of skills, such as a second language (L2) and musical expertise. It is difficult to reconcile the negative consequence this traditional view entails for learning after a sensitive period with our current understanding of the brain's ability for experience-dependent plasticity across the lifespan. What is needed is a better understanding of the mechanisms underlying auditory learning and plasticity at different points in development. Drawing on research in language development and music training, this review examines not only what we learn and when we learn it, but also how learning occurs at different ages. First, we discuss differences in the mechanism of learning and plasticity during and after a sensitive period by examining how language exposure versus training forms language-specific phonetic representations in infants and adult L2 learners, respectively. Second, we examine the impact of musical training that begins at different ages on behavioral and neural indices of auditory and motor processing as well as sensorimotor integration. Third, we examine the extent to which childhood training in one auditory domain can enhance processing in another domain via the transfer of learning between shared neuro-cognitive systems. Specifically, we review evidence for a potential bi-directional transfer of skills between music and language by examining how speaking a tonal language may enhance music processing and, conversely, how early music training can enhance language processing. We conclude with a discussion of the role of attention in auditory learning for learning during and after sensitive periods and outline avenues of future research.

  4. Learning, neural plasticity and sensitive periods: implications for language acquisition, music training and transfer across the lifespan

    PubMed Central

    White, Erin J.; Hutka, Stefanie A.; Williams, Lynne J.; Moreno, Sylvain

    2013-01-01

    Sensitive periods in human development have often been proposed to explain age-related differences in the attainment of a number of skills, such as a second language (L2) and musical expertise. It is difficult to reconcile the negative consequence this traditional view entails for learning after a sensitive period with our current understanding of the brain’s ability for experience-dependent plasticity across the lifespan. What is needed is a better understanding of the mechanisms underlying auditory learning and plasticity at different points in development. Drawing on research in language development and music training, this review examines not only what we learn and when we learn it, but also how learning occurs at different ages. First, we discuss differences in the mechanism of learning and plasticity during and after a sensitive period by examining how language exposure versus training forms language-specific phonetic representations in infants and adult L2 learners, respectively. Second, we examine the impact of musical training that begins at different ages on behavioral and neural indices of auditory and motor processing as well as sensorimotor integration. Third, we examine the extent to which childhood training in one auditory domain can enhance processing in another domain via the transfer of learning between shared neuro-cognitive systems. Specifically, we review evidence for a potential bi-directional transfer of skills between music and language by examining how speaking a tonal language may enhance music processing and, conversely, how early music training can enhance language processing. We conclude with a discussion of the role of attention in auditory learning for learning during and after sensitive periods and outline avenues of future research. PMID:24312022

  5. Reaction-diffusion-like formalism for plastic neural networks reveals dissipative solitons at criticality

    NASA Astrophysics Data System (ADS)

    Grytskyy, Dmytro; Diesmann, Markus; Helias, Moritz

    2016-06-01

    Self-organized structures in networks with spike-timing dependent synaptic plasticity (STDP) are likely to play a central role for information processing in the brain. In the present study we derive a reaction-diffusion-like formalism for plastic feed-forward networks of nonlinear rate-based model neurons with a correlation sensitive learning rule inspired by and being qualitatively similar to STDP. After obtaining equations that describe the change of the spatial shape of the signal from layer to layer, we derive a criterion for the nonlinearity necessary to obtain stable dynamics for arbitrary input. We classify the possible scenarios of signal evolution and find that close to the transition to the unstable regime metastable solutions appear. The form of these dissipative solitons is determined analytically and the evolution and interaction of several such coexistent objects is investigated.

  6. Reaction-diffusion-like formalism for plastic neural networks reveals dissipative solitons at criticality.

    PubMed

    Grytskyy, Dmytro; Diesmann, Markus; Helias, Moritz

    2016-06-01

    Self-organized structures in networks with spike-timing dependent synaptic plasticity (STDP) are likely to play a central role for information processing in the brain. In the present study we derive a reaction-diffusion-like formalism for plastic feed-forward networks of nonlinear rate-based model neurons with a correlation sensitive learning rule inspired by and being qualitatively similar to STDP. After obtaining equations that describe the change of the spatial shape of the signal from layer to layer, we derive a criterion for the nonlinearity necessary to obtain stable dynamics for arbitrary input. We classify the possible scenarios of signal evolution and find that close to the transition to the unstable regime metastable solutions appear. The form of these dissipative solitons is determined analytically and the evolution and interaction of several such coexistent objects is investigated. PMID:27415276

  7. Neural Plasticity following Abacus Training in Humans: A Review and Future Directions

    PubMed Central

    Li, Yongxin; Chen, Feiyan; Huang, Wenhua

    2016-01-01

    The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact. PMID:26881089

  8. Neural Plasticity following Abacus Training in Humans: A Review and Future Directions.

    PubMed

    Li, Yongxin; Chen, Feiyan; Huang, Wenhua

    2016-01-01

    The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact.

  9. Spatiotemporal discrimination in neural networks with short-term synaptic plasticity

    NASA Astrophysics Data System (ADS)

    Shlaer, Benjamin; Miller, Paul

    2015-03-01

    Cells in recurrently connected neural networks exhibit bistability, which allows for stimulus information to persist in a circuit even after stimulus offset, i.e. short-term memory. However, such a system does not have enough hysteresis to encode temporal information about the stimuli. The biophysically described phenomenon of synaptic depression decreases synaptic transmission strengths due to increased presynaptic activity. This short-term reduction in synaptic strengths can destabilize attractor states in excitatory recurrent neural networks, causing the network to move along stimulus dependent dynamical trajectories. Such a network can successfully separate amplitudes and durations of stimuli from the number of successive stimuli. Stimulus number, duration and intensity encoding in randomly connected attractor networks with synaptic depression. Front. Comput. Neurosci. 7:59., and so provides a strong candidate network for the encoding of spatiotemporal information. Here we explicitly demonstrate the capability of a recurrent neural network with short-term synaptic depression to discriminate between the temporal sequences in which spatial stimuli are presented.

  10. Habituation, sensitization, and Pavlovian conditioning

    PubMed Central

    Çevik, Münire Özlem

    2014-01-01

    In this brief review, I argue that the impact of a stimulus on behavioral control increase as the distance of the stimulus to the body decreases. Habituation, i.e., decrement in response intensity repetition of the triggering stimulus, is the default state for sensory processing, and the likelihood of habituation is higher for distal stimuli. Sensitization, i.e., increment in response intensity upon stimulus repetition, occurs in a state dependent manner for proximal stimuli that make direct contact with the body. In Pavlovian conditioning paradigms, the unconditioned stimulus (US) is always a more proximal stimulus than the conditioned stimulus (CS). The mechanisms of associative and non-associative learning are not independent. CS−US pairings lead to formation of associations if sensitizing modulation from a proximal US prevents the habituation for a distal anticipatory CS. PMID:24574983

  11. Habituation, sensitization, and Pavlovian conditioning.

    PubMed

    Cevik, Münire Özlem

    2014-01-01

    In this brief review, I argue that the impact of a stimulus on behavioral control increase as the distance of the stimulus to the body decreases. Habituation, i.e., decrement in response intensity repetition of the triggering stimulus, is the default state for sensory processing, and the likelihood of habituation is higher for distal stimuli. Sensitization, i.e., increment in response intensity upon stimulus repetition, occurs in a state dependent manner for proximal stimuli that make direct contact with the body. In Pavlovian conditioning paradigms, the unconditioned stimulus (US) is always a more proximal stimulus than the conditioned stimulus (CS). The mechanisms of associative and non-associative learning are not independent. CS-US pairings lead to formation of associations if sensitizing modulation from a proximal US prevents the habituation for a distal anticipatory CS. PMID:24574983

  12. Physiological, Molecular and Genetic Mechanisms of Long-Term Habituation

    SciTech Connect

    Calin-Jageman, Robert J

    2009-09-12

    Work funded on this grant has explored the mechanisms of long-term habituation, a ubiquitous form of learning that plays a key role in basic cognitive functioning. Specifically, behavioral, physiological, and molecular mechanisms of habituation have been explored using a simple model system, the tail-elicited siphon-withdrawal reflex (T-SWR) in the marine mollusk Aplysia californica. Substantial progress has been made on the first and third aims, providing some fundamental insights into the mechanisms by which memories are stored. We have characterized the physiological correlates of short- and long-term habituation. We found that short-term habituation is accompanied by a robust sensory adaptation, whereas long-term habituation is accompanied by alterations in sensory and interneuron synaptic efficacy. Thus, our data indicates memories can be shifted between different sites in a neural network as they are consolidated from short to long term. At the molecular level, we have accomplished microarray analysis comparing gene expression in both habituated and control ganglia. We have identified a network of putatively regulated transcripts that seems particularly targeted towards synaptic changes (e.g. SNAP25, calmodulin) . We are now beginning additional work to confirm regulation of these transcripts and build a more detailed understanding of the cascade of molecular events leading to the permanent storage of long-term memories. On the third aim, we have fostered a nascent neuroscience program via a variety of successful initiatives. We have funded over 11 undergraduate neuroscience scholars, several of whom have been recognized at national and regional levels for their research. We have also conducted a pioneering summer research program for community college students which is helping enhance access of underrepresented groups to life science careers. Despite minimal progress on the second aim, this project has provided a) novel insight into the network mechanisms by

  13. Sensitization and habituation regulate reinforcer effectiveness.

    PubMed

    McSweeney, Frances K; Murphy, Eric S

    2009-09-01

    We argue that sensitization and habituation occur to the sensory properties of reinforcers when those reinforcers are presented repeatedly or for a prolonged time. Sensitization increases, and habituation decreases, the ability of a reinforcer to control behavior. Supporting this argument, the rate of operant responding changes systematically within experimental sessions even when the programmed rate of reinforcement is held constant across the session. These within-session changes in operant responding are produced by repeated delivery of the reinforcer, and their empirical characteristics correspond to the characteristics of behavior undergoing sensitization and habituation. Two characteristics of habituation (dishabituation, stimulus specificity) are particularly useful in separating habituation from alternative explanations. Arguing that habituation occurs to reinforcers expands the domain of habituation. The argument implies that habituation occurs to biologically important, not just to neutral, stimuli. The argument also implies that habituation may be observed in "voluntary" (operant), not just in reflexive, behavior. Expanding the domain of habituation has important implications for understanding operant and classical conditioning. Habituation may also contribute to the regulation of motivated behaviors. Habituation provides a more accurate and a less cumbersome explanation for motivated behaviors than homeostasis. Habituation also has some surprising, and easily testable, implications for the control of motivated behaviors.

  14. Behavioral and neural plasticity caused by early social experiences: the case of the honeybee

    PubMed Central

    Arenas, Andrés; Ramírez, Gabriela P.; Balbuena, María Sol; Farina, Walter M.

    2013-01-01

    Cognitive experiences during the early stages of life play an important role in shaping future behavior. Behavioral and neural long-term changes after early sensory and associative experiences have been recently reported in the honeybee. This invertebrate is an excellent model for assessing the role of precocious experiences on later behavior due to its extraordinarily tuned division of labor based on age polyethism. These studies are mainly focused on the role and importance of experiences occurred during the first days of the adult lifespan, their impact on foraging decisions, and their contribution to coordinate food gathering. Odor-rewarded experiences during the first days of honeybee adulthood alter the responsiveness to sucrose, making young hive bees more sensitive to assess gustatory features about the nectar brought back to the hive and affecting the dynamic of the food transfers and the propagation of food-related information within the colony. Early olfactory experiences lead to stable and long-term associative memories that can be successfully recalled after many days, even at foraging ages. Also they improve memorizing of new associative learning events later in life. The establishment of early memories promotes stable reorganization of the olfactory circuits inducing structural and functional changes in the antennal lobe (AL). Early rewarded experiences have relevant consequences at the social level too, biasing dance and trophallaxis partner choice and affecting recruitment. Here, we revised recent results in bees' physiology, behavior, and sociobiology to depict how the early experiences affect their cognition abilities and neural-related circuits. PMID:23986708

  15. Criminal Careers of Habitual Felons.

    ERIC Educational Resources Information Center

    Petersilia, Joan; And Others

    The criminal development of habitual felons was examined by means of lengthy interviews with 49 prison inmates, all armed robbers serving at least their second prison terms. Results are not considered generalized, but should be regarded as 49 case studies. Although some of the findings were consistent with traditional images (juvenile offender…

  16. In vivo reactive neural plasticity investigation by means of correlative two photon: electron microscopy

    NASA Astrophysics Data System (ADS)

    Allegra Mascaro, A. L.; Cesare, P.; Sacconi, L.; Grasselli, G.; Mandolesi, G.; Maco, B.; Knott, G.; Huang, L.; De Paola, V.; Strata, P.; Pavone, F. S.

    2013-02-01

    In the adult nervous system, different populations of neurons correspond to different regenerative behavior. Although previous works showed that olivocerebellar fibers are capable of axonal regeneration in a suitable environment as a response to injury1, we have hitherto no details about the real dynamics of fiber regeneration. We set up a model of singularly axotomized climbing fibers (CF) to investigate their reparative properties in the adult central nervous system (CNS) in vivo. Time lapse two-photon imaging has been combined to laser nanosurgery2, 3 to define a temporal pattern of the degenerative event and to follow the structural rearrangement after injury. To characterize the damage and to elucidate the possible formation of new synaptic contacts on the sprouted branches of the lesioned CF, we combined two-photon in vivo imaging with block face scanning electron microscopy (FIB-SEM). Here we describe the approach followed to characterize the reactive plasticity after injury.

  17. Heterogeneous mean field for neural networks with short-term plasticity

    NASA Astrophysics Data System (ADS)

    di Volo, Matteo; Burioni, Raffaella; Casartelli, Mario; Livi, Roberto; Vezzani, Alessandro

    2014-08-01

    We report about the main dynamical features of a model of leaky integrate-and-fire excitatory neurons with short-term plasticity defined on random massive networks. We investigate the dynamics by use of a heterogeneous mean-field formulation of the model that is able to reproduce dynamical phases characterized by the presence of quasisynchronous events. This formulation allows one to solve also the inverse problem of reconstructing the in-degree distribution for different network topologies from the knowledge of the global activity field. We study the robustness of this inversion procedure by providing numerical evidence that the in-degree distribution can be recovered also in the presence of noise and disorder in the external currents. Finally, we discuss the validity of the heterogeneous mean-field approach for sparse networks with a sufficiently large average in-degree.

  18. Effects of bursting dynamic features on the generation of multi-clustered structure of neural network with symmetric spike-timing-dependent plasticity learning rule

    SciTech Connect

    Liu, Hui; Song, Yongduan; Xue, Fangzheng; Li, Xiumin

    2015-11-15

    In this paper, the generation of multi-clustered structure of self-organized neural network with different neuronal firing patterns, i.e., bursting or spiking, has been investigated. The initially all-to-all-connected spiking neural network or bursting neural network can be self-organized into clustered structure through the symmetric spike-timing-dependent plasticity learning for both bursting and spiking neurons. However, the time consumption of this clustering procedure of the burst-based self-organized neural network (BSON) is much shorter than the spike-based self-organized neural network (SSON). Our results show that the BSON network has more obvious small-world properties, i.e., higher clustering coefficient and smaller shortest path length than the SSON network. Also, the results of larger structure entropy and activity entropy of the BSON network demonstrate that this network has higher topological complexity and dynamical diversity, which benefits for enhancing information transmission of neural circuits. Hence, we conclude that the burst firing can significantly enhance the efficiency of clustering procedure and the emergent clustered structure renders the whole network more synchronous and therefore more sensitive to weak input. This result is further confirmed from its improved performance on stochastic resonance. Therefore, we believe that the multi-clustered neural network which self-organized from the bursting dynamics has high efficiency in information processing.

  19. Effects of bursting dynamic features on the generation of multi-clustered structure of neural network with symmetric spike-timing-dependent plasticity learning rule.

    PubMed

    Liu, Hui; Song, Yongduan; Xue, Fangzheng; Li, Xiumin

    2015-11-01

    In this paper, the generation of multi-clustered structure of self-organized neural network with different neuronal firing patterns, i.e., bursting or spiking, has been investigated. The initially all-to-all-connected spiking neural network or bursting neural network can be self-organized into clustered structure through the symmetric spike-timing-dependent plasticity learning for both bursting and spiking neurons. However, the time consumption of this clustering procedure of the burst-based self-organized neural network (BSON) is much shorter than the spike-based self-organized neural network (SSON). Our results show that the BSON network has more obvious small-world properties, i.e., higher clustering coefficient and smaller shortest path length than the SSON network. Also, the results of larger structure entropy and activity entropy of the BSON network demonstrate that this network has higher topological complexity and dynamical diversity, which benefits for enhancing information transmission of neural circuits. Hence, we conclude that the burst firing can significantly enhance the efficiency of clustering procedure and the emergent clustered structure renders the whole network more synchronous and therefore more sensitive to weak input. This result is further confirmed from its improved performance on stochastic resonance. Therefore, we believe that the multi-clustered neural network which self-organized from the bursting dynamics has high efficiency in information processing.

  20. Gene-environment interactions and the enteric nervous system: Neural plasticity and Hirschsprung disease prevention.

    PubMed

    Heuckeroth, Robert O; Schäfer, Karl-Herbert

    2016-09-15

    Intestinal function is primarily controlled by an intrinsic nervous system of the bowel called the enteric nervous system (ENS). The cells of the ENS are neural crest derivatives that migrate into and through the bowel during early stages of organogenesis before differentiating into a wide variety of neurons and glia. Although genetic factors critically underlie ENS development, it is now clear that many non-genetic factors may influence the number of enteric neurons, types of enteric neurons, and ratio of neurons to glia. These non-genetic influences include dietary nutrients and medicines that may impact ENS structure and function before or after birth. This review summarizes current data about gene-environment interactions that affect ENS development and suggests that these factors may contribute to human intestinal motility disorders like Hirschsprung disease or irritable bowel syndrome.

  1. Speech Sound Processing Deficits and Training-Induced Neural Plasticity in Rats with Dyslexia Gene Knockdown

    PubMed Central

    Centanni, Tracy M.; Chen, Fuyi; Booker, Anne M.; Engineer, Crystal T.; Sloan, Andrew M.; Rennaker, Robert L.; LoTurco, Joseph J.; Kilgard, Michael P.

    2014-01-01

    In utero RNAi of the dyslexia-associated gene Kiaa0319 in rats (KIA-) degrades cortical responses to speech sounds and increases trial-by-trial variability in onset latency. We tested the hypothesis that KIA- rats would be impaired at speech sound discrimination. KIA- rats needed twice as much training in quiet conditions to perform at control levels and remained impaired at several speech tasks. Focused training using truncated speech sounds was able to normalize speech discrimination in quiet and background noise conditions. Training also normalized trial-by-trial neural variability and temporal phase locking. Cortical activity from speech trained KIA- rats was sufficient to accurately discriminate between similar consonant sounds. These results provide the first direct evidence that assumed reduced expression of the dyslexia-associated gene KIAA0319 can cause phoneme processing impairments similar to those seen in dyslexia and that intensive behavioral therapy can eliminate these impairments. PMID:24871331

  2. Speech sound processing deficits and training-induced neural plasticity in rats with dyslexia gene knockdown.

    PubMed

    Centanni, Tracy M; Chen, Fuyi; Booker, Anne M; Engineer, Crystal T; Sloan, Andrew M; Rennaker, Robert L; LoTurco, Joseph J; Kilgard, Michael P

    2014-01-01

    In utero RNAi of the dyslexia-associated gene Kiaa0319 in rats (KIA-) degrades cortical responses to speech sounds and increases trial-by-trial variability in onset latency. We tested the hypothesis that KIA- rats would be impaired at speech sound discrimination. KIA- rats needed twice as much training in quiet conditions to perform at control levels and remained impaired at several speech tasks. Focused training using truncated speech sounds was able to normalize speech discrimination in quiet and background noise conditions. Training also normalized trial-by-trial neural variability and temporal phase locking. Cortical activity from speech trained KIA- rats was sufficient to accurately discriminate between similar consonant sounds. These results provide the first direct evidence that assumed reduced expression of the dyslexia-associated gene KIAA0319 can cause phoneme processing impairments similar to those seen in dyslexia and that intensive behavioral therapy can eliminate these impairments. PMID:24871331

  3. Human Neural Stem Cell Transplantation Provides Long-Term Restoration of Neuronal Plasticity in the Irradiated Hippocampus

    PubMed Central

    Acharya, Munjal M.; Rosi, Susanna; Jopson, Timothy; Limoli, Charles L.

    2016-01-01

    For the majority of CNS malignancies, radiotherapy provides the best option for forestalling tumor growth, but is frequently associated with debilitating and progressive cognitive dysfunction. Despite the recognition of this serious side effect, satisfactory long-term solutions are not currently available and have prompted our efforts to explore the potential therapeutic efficacy of cranial stem cell transplants. We have demonstrated that intrahippocampal transplantation of human neural stem cells (hNSCs) can provide long-lasting cognitive benefits using an athymic rat model subjected to cranial irradiation. To explore the possible mechanisms underlying the capability of engrafted cells to ameliorate radiation-induced cognitive dysfunction we analyzed the expression patterns of the behaviorally induced activity-regulated cytoskeleton-associated protein (Arc) in the hippocampus at 1 and 8 months postgrafting. While immunohistochemical analyses revealed a small fraction (4.5%) of surviving hNSCs in the irradiated brain that did not express neuronal or astroglial makers, hNSC transplantation impacted the irradiated microenvironment of the host brain by promoting the expression of Arc at both time points. Arc is known to play key roles in the neuronal mechanisms underlying long-term synaptic plasticity and memory and provides a reliable marker for detecting neurons that are actively engaged in spatial and contextual information processing associated with memory consolidation. Cranial irradiation significantly reduced the number of pyramidal (CA1) and granule neurons (DG) expressing behaviorally induced Arc at 1 and 8 months postirradiation. Transplantation of hNSCs restored the expression of plasticity-related Arc in the host brain to control levels. These findings suggest that hNSC transplantation promotes the long-term recovery of host hippocampal neurons and indicates that one mechanism promoting the preservation of cognition after irradiation involves trophic

  4. Modeling gravity-dependent plasticity of the angular vestibuloocular reflex with a physiologically based neural network.

    PubMed

    Xiang, Yongqing; Yakushin, Sergei B; Cohen, Bernard; Raphan, Theodore

    2006-12-01

    A neural network model was developed to explain the gravity-dependent properties of gain adaptation of the angular vestibuloocular reflex (aVOR). Gain changes are maximal at the head orientation where the gain is adapted and decrease as the head is tilted away from that position and can be described by the sum of gravity-independent and gravity-dependent components. The adaptation process was modeled by modifying the weights and bias values of a three-dimensional physiologically based neural network of canal-otolith-convergent neurons that drive the aVOR. Model parameters were trained using experimental vertical aVOR gain values. The learning rule aimed to reduce the error between eye velocities obtained from experimental gain values and model output in the position of adaptation. Although the model was trained only at specific head positions, the model predicted the experimental data at all head positions in three dimensions. Altering the relative learning rates of the weights and bias improved the model-data fits. Model predictions in three dimensions compared favorably with those of a double-sinusoid function, which is a fit that minimized the mean square error at every head position and served as the standard by which we compared the model predictions. The model supports the hypothesis that gravity-dependent adaptation of the aVOR is realized in three dimensions by a direct otolith input to canal-otolith neurons, whose canal sensitivities are adapted by the visual-vestibular mismatch. The adaptation is tuned by how the weights from otolith input to the canal-otolith-convergent neurons are adapted for a given head orientation.

  5. Neural Plasticity and Memory: Is Memory Encoded in Hydrogen Bonding Patterns?

    PubMed

    Amtul, Zareen; Rahman, Atta-Ur

    2016-02-01

    Current models of memory storage recognize posttranslational modification vital for short-term and mRNA translation for long-lasting information storage. However, at the molecular level things are quite vague. A comprehensive review of the molecular basis of short and long-lasting synaptic plasticity literature leads us to propose that the hydrogen bonding pattern at the molecular level may be a permissive, vital step of memory storage. Therefore, we propose that the pattern of hydrogen bonding network of biomolecules (glycoproteins and/or DNA template, for instance) at the synapse is the critical edifying mechanism essential for short- and long-term memories. A novel aspect of this model is that nonrandom impulsive (or unplanned) synaptic activity functions as a synchronized positive-feedback rehearsal mechanism by revising the configurations of the hydrogen bonding network by tweaking the earlier tailored hydrogen bonds. This process may also maintain the elasticity of the related synapses involved in memory storage, a characteristic needed for such networks to alter intricacy and revise endlessly. The primary purpose of this review is to stimulate the efforts to elaborate the mechanism of neuronal connectivity both at molecular and chemical levels.

  6. Cortical stimulation consolidates and reactivates visual experience: neural plasticity from magnetic entrainment of visual activity.

    PubMed

    Liao, Hsin-I; Wu, Daw-An; Halelamien, Neil; Shimojo, Shinsuke

    2013-01-01

    Delivering transcranial magnetic stimulation (TMS) shortly after the end of a visual stimulus can cause a TMS-induced 'replay' or 'visual echo' of the visual percept. In the current study, we find an entrainment effect that after repeated elicitations of TMS-induced replay with the same visual stimulus, the replay can be induced by TMS alone, without the need for the physical visual stimulus. In Experiment 1, we used a subjective rating task to examine the phenomenal aspects of TMS-entrained replays. In Experiment 2, we used an objective masking paradigm to quantitatively validate the phenomenon and to examine the involvement of low-level mechanisms. Results showed that the TMS-entrained replay was not only phenomenally experienced (Exp.1), but also able to hamper letter identification (Exp.2). The findings have implications in several directions: (1) the visual cortical representation and iconic memory, (2) experience-based plasticity in the visual cortex, and (3) their relationship to visual awareness. PMID:23863977

  7. Neural plasticity explored by correlative two-photon and electron/SPIM microscopy

    NASA Astrophysics Data System (ADS)

    Allegra Mascaro, A. L.; Silvestri, L.; Costantini, I.; Sacconi, L.; Maco, B.; Knott, G. W.; Pavone, F. S.

    2013-06-01

    Plasticity of the central nervous system is a complex process which involves the remodeling of neuronal processes and synaptic contacts. However, a single imaging technique can reveal only a small part of this complex machinery. To obtain a more complete view, complementary approaches should be combined. Two-photon fluorescence microscopy, combined with multi-photon laser nanosurgery, allow following the real-time dynamics of single neuronal processes in the cerebral cortex of living mice. The structural rearrangement elicited by this highly confined paradigm of injury can be imaged in vivo first, and then the same neuron could be retrieved ex-vivo and characterized in terms of ultrastructural features of the damaged neuronal branch by means of electron microscopy. Afterwards, we describe a method to integrate data from in vivo two-photon fluorescence imaging and ex vivo light sheet microscopy, based on the use of major blood vessels as reference chart. We show how the apical dendritic arbor of a single cortical pyramidal neuron imaged in living mice can be found in the large-scale brain reconstruction obtained with light sheet microscopy. Starting from its apical portion, the whole pyramidal neuron can then be segmented and located in the correct cortical layer. With the correlative approach presented here, researchers will be able to place in a three-dimensional anatomic context the neurons whose dynamics have been observed with high detail in vivo.

  8. Adventures in neural plasticity, aging, and neurodegenerative disorders aboard the CWC beagle.

    PubMed

    Mattson, Mark P

    2003-11-01

    This article recounts some of the scientific endeavors of Carl W. Cotman (CWC) during his journeys through the cellular circuitry of the mammalian brain. I have selected for consideration his findings that have been an important impetus for my own research; in several cases our different experiments have provided complementary data to support an hypothesis. Three examples are (i) Carl's studies of the roles of glutamate in synaptic transmission and plasticity in the adult brain and my studies of how glutamate regulates neurite outgrowth and cell survival in brain development; (ii) his and our studies of the mechanisms whereby amyloid beta-peptide damages and kills neurons; and (iii) Carl's evidence that physical activity regulates neurotrophin levels in the brain and our evidence that dietary restriction has similar effects and is neuroprotective. In case you have not yet realized how I chose a title for this article it is because Carl has a (very distant) connection with Charles Darwin-Darwin sailed on a vessel called the Beagle and Carl has studied beagle dogs, establishing them as a model for understanding the neurobiology of human brain aging.

  9. Neural Plasticity After Pre-Linguistic Injury to the Arcuate and Superior Longitudinal Fasciculi

    PubMed Central

    Yeatman, Jason D; Feldman, Heidi M

    2011-01-01

    We describe the case of girl who was born prematurely and diagnosed periventricular leukomalacia, a condition characterized by severe injury to the white matter tracts primarily surrounding the ventricles. At 12 years of age, we obtained diffusion tensor imaging (DTI) data on this child as part of a research protocol. Multiple analyses of DTI data, including tractography, showed that the left and right arcuate and superior longitudinal fasciculi were missing in the child though all other major white matter tracts were present. Standardized psychometric tests at age 12 years revealed that despite early language delays, she had average scores on expressive language, sentence repetition, and reading, functions that have been hypothesized to depend on signals carried by the arcuate fasciculus. We identified intact ventral connections between the temporal and frontal lobes through the extreme capsule fiber system and uncinate fasciculus. Preserved language and reading function after serious injury to the arcuate fasciculus highlights the plasticity of the developing brain after severe white matter injury early in life. PMID:21937035

  10. Acoustic Emission Source Location in Unidirectional Carbon-Fibre-Reinforced Plastic Plates Using Virtually Trained Artificial Neural Networks

    SciTech Connect

    Caprino, G.; Lopresto, V.; Leone, C.; Papa, I.

    2010-06-02

    Acoustic emission source location in a unidirectional carbon-fibre-reinforced plastic plate was attempted employing Artificial Neural Network (ANN) technology. The acoustic emission events were produced by a lead break, and the response wave received by piezoelectric sensors, type VS150-M resonant at 150 kHz. The waves were detected by a Vallen AMSY4 eight-channel instrumentation. The time of arrival, determined through the conventional threshold crossing technique, was used to measure the dependence of wave velocity on fibre orientation. A simple empirical formula, relying on classical lamination and suggested by wave propagation theory, was able to accurately model the experimental trend. Based on the formula, virtual training and testing data sets were generated for the case of a plate monitored by three transducers, and adopted to select two potentially effective ANN architectures. For final validation, experimental tests were carried out, positioning the source at predetermined points evenly distributed within the plate area. A very satisfactory correlation was found between the actual source locations and the ANN predictions.

  11. Acoustic Emission Source Location in Unidirectional Carbon-Fibre-Reinforced Plastic Plates Using Virtually Trained Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Caprino, G.; Lopresto, V.; Leone, C.; Papa, I.

    2010-06-01

    Acoustic emission source location in a unidirectional carbon-fibre-reinforced plastic plate was attempted employing Artificial Neural Network (ANN) technology. The acoustic emission events were produced by a lead break, and the response wave received by piezoelectric sensors, type VS150-M resonant at 150 kHz. The waves were detected by a Vallen AMSY4 eight-channel instrumentation. The time of arrival, determined through the conventional threshold crossing technique, was used to measure the dependence of wave velocity on fibre orientation. A simple empirical formula, relying on classical lamination and suggested by wave propagation theory, was able to accurately model the experimental trend. Based on the formula, virtual training and testing data sets were generated for the case of a plate monitored by three transducers, and adopted to select two potentially effective ANN architectures. For final validation, experimental tests were carried out, positioning the source at predetermined points evenly distributed within the plate area. A very satisfactory correlation was found between the actual source locations and the ANN predictions.

  12. Prediction of Damage Factor in end Milling of Glass Fibre Reinforced Plastic Composites Using Artificial Neural Network

    NASA Astrophysics Data System (ADS)

    Erkan, Ömer; Işık, Birhan; Çiçek, Adem; Kara, Fuat

    2013-08-01

    Glass fibre reinforced plastic (GFRP) composites are an economic alternative to engineering materials because of their superior properties. Some damages on the surface occur due to their complex cutting mechanics in cutting process. Minimisation of the damages is fairly important in terms of product quality. In this study, a GFRP composite material was milled to experimentally minimise the damages on the machined surfaces, using two, three and four flute end mills at different combinations of cutting parameters. Experimental results showed that the damage factor increased with increasing cutting speed and feed rate, on the other hand, it was found that the damage factor decreased with increasing depth of cut and number of the flutes. In addition, analysis of variance (ANOVA) results clearly revealed that the feed rate was the most influential parameter affecting the damage factor in end milling of GFRP composites. Also, in present study, Artificial Neural Network (ANN) models with five learning algorithms were used in predicting the damage factor to reduce number of expensive and time-consuming experiments. The highest performance was obtained by 4-10-1 network structure with LM learning algorithm. ANN was notably successful in predicting the damage factor due to higher R2 and lower RMSE and MEP.

  13. Excessive Sensory Stimulation during Development Alters Neural Plasticity and Vulnerability to Cocaine in Mice.

    PubMed

    Ravinder, Shilpa; Donckels, Elizabeth A; Ramirez, Julian S B; Christakis, Dimitri A; Ramirez, Jan-Marino; Ferguson, Susan M

    2016-01-01

    Early life experiences affect the formation of neuronal networks, which can have a profound impact on brain function and behavior later in life. Previous work has shown that mice exposed to excessive sensory stimulation during development are hyperactive and novelty seeking, and display impaired cognition compared with controls. In this study, we addressed the issue of whether excessive sensory stimulation during development could alter behaviors related to addiction and underlying circuitry in CD-1 mice. We found that the reinforcing properties of cocaine were significantly enhanced in mice exposed to excessive sensory stimulation. Moreover, although these mice displayed hyperactivity that became more pronounced over time, they showed impaired persistence of cocaine-induced locomotor sensitization. These behavioral effects were associated with alterations in glutamatergic transmission in the nucleus accumbens and amygdala. Together, these findings suggest that excessive sensory stimulation in early life significantly alters drug reward and the neural circuits that regulate addiction and attention deficit hyperactivity. These observations highlight the consequences of early life experiences and may have important implications for children growing up in today's complex technological environment. PMID:27588306

  14. Excessive Sensory Stimulation during Development Alters Neural Plasticity and Vulnerability to Cocaine in Mice

    PubMed Central

    Ravinder, Shilpa; Christakis, Dimitri A.

    2016-01-01

    Abstract Early life experiences affect the formation of neuronal networks, which can have a profound impact on brain function and behavior later in life. Previous work has shown that mice exposed to excessive sensory stimulation during development are hyperactive and novelty seeking, and display impaired cognition compared with controls. In this study, we addressed the issue of whether excessive sensory stimulation during development could alter behaviors related to addiction and underlying circuitry in CD-1 mice. We found that the reinforcing properties of cocaine were significantly enhanced in mice exposed to excessive sensory stimulation. Moreover, although these mice displayed hyperactivity that became more pronounced over time, they showed impaired persistence of cocaine-induced locomotor sensitization. These behavioral effects were associated with alterations in glutamatergic transmission in the nucleus accumbens and amygdala. Together, these findings suggest that excessive sensory stimulation in early life significantly alters drug reward and the neural circuits that regulate addiction and attention deficit hyperactivity. These observations highlight the consequences of early life experiences and may have important implications for children growing up in today’s complex technological environment. PMID:27588306

  15. Neural bases of childhood speech disorders: lateralization and plasticity for speech functions during development.

    PubMed

    Liégeois, Frédérique J; Morgan, Angela T

    2012-01-01

    Current models of speech production in adults emphasize the crucial role played by the left perisylvian cortex, primary and pre-motor cortices, the basal ganglia, and the cerebellum for normal speech production. Whether similar brain-behaviour relationships and leftward cortical dominance are found in childhood remains unclear. Here we reviewed recent evidence linking motor speech disorders (apraxia of speech and dysarthria) and brain abnormalities in children and adolescents with developmental, progressive, or childhood-acquired conditions. We found no evidence that unilateral damage can result in apraxia of speech, or that left hemisphere lesions are more likely to result in dysarthria than lesion to the right. The few studies reporting on childhood apraxia of speech converged towards morphological, structural, metabolic or epileptic anomalies affecting the basal ganglia, perisylvian and rolandic cortices bilaterally. Persistent dysarthria, similarly, was commonly reported in individuals with syndromes and conditions affecting these same structures bilaterally. In conclusion, for the first time we provide evidence that longterm and severe childhood speech disorders result predominantly from bilateral disruption of the neural networks involved in speech production.

  16. Odor Experiences during Preimaginal Stages Cause Behavioral and Neural Plasticity in Adult Honeybees.

    PubMed

    Ramírez, Gabriela; Fagundez, Carol; Grosso, Juan P; Argibay, Pablo; Arenas, Andrés; Farina, Walter M

    2016-01-01

    In eusocial insects, experiences acquired during the development have long-term consequences on mature behavior. In the honeybee that suffers profound changes associated with metamorphosis, the effect of odor experiences at larval instars on the subsequent physiological and behavioral response is still unclear. To address the impact of preimaginal experiences on the adult honeybee, colonies containing larvae were fed scented food. The effect of the preimaginal experiences with the food odor was assessed in learning performance, memory retention and generalization in 3-5- and 17-19 day-old bees, in the regulation of their expression of synaptic-related genes and in the perception and morphology of their antennae. Three-five day old bees that experienced 1-hexanol (1-HEX) as food scent responded more to the presentation of the odor during the 1-HEX conditioning than control bees (i.e., bees reared in colonies fed unscented food). Higher levels of proboscis extension response (PER) to 1-HEX in this group also extended to HEXA, the most perceptually similar odor to the experienced one that we tested. These results were not observed for the group tested at older ages. In the brain of young adults, larval experiences triggered similar levels of neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have been involved in synaptic formation after associative learning. At the sensory periphery, the experience did not alter the number of the olfactory sensilla placoidea, but did reduce the electrical response of the antennae to the experienced and novel odor. Our study provides a new insight into the effects of preimaginal experiences in the honeybee and the mechanisms underlying olfactory plasticity at larval stage of holometabolous insects.

  17. Odor Experiences during Preimaginal Stages Cause Behavioral and Neural Plasticity in Adult Honeybees

    PubMed Central

    Ramírez, Gabriela; Fagundez, Carol; Grosso, Juan P.; Argibay, Pablo; Arenas, Andrés; Farina, Walter M.

    2016-01-01

    In eusocial insects, experiences acquired during the development have long-term consequences on mature behavior. In the honeybee that suffers profound changes associated with metamorphosis, the effect of odor experiences at larval instars on the subsequent physiological and behavioral response is still unclear. To address the impact of preimaginal experiences on the adult honeybee, colonies containing larvae were fed scented food. The effect of the preimaginal experiences with the food odor was assessed in learning performance, memory retention and generalization in 3–5- and 17–19 day-old bees, in the regulation of their expression of synaptic-related genes and in the perception and morphology of their antennae. Three-five day old bees that experienced 1-hexanol (1-HEX) as food scent responded more to the presentation of the odor during the 1-HEX conditioning than control bees (i.e., bees reared in colonies fed unscented food). Higher levels of proboscis extension response (PER) to 1-HEX in this group also extended to HEXA, the most perceptually similar odor to the experienced one that we tested. These results were not observed for the group tested at older ages. In the brain of young adults, larval experiences triggered similar levels of neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have been involved in synaptic formation after associative learning. At the sensory periphery, the experience did not alter the number of the olfactory sensilla placoidea, but did reduce the electrical response of the antennae to the experienced and novel odor. Our study provides a new insight into the effects of preimaginal experiences in the honeybee and the mechanisms underlying olfactory plasticity at larval stage of holometabolous insects. PMID:27375445

  18. Odor Experiences during Preimaginal Stages Cause Behavioral and Neural Plasticity in Adult Honeybees.

    PubMed

    Ramírez, Gabriela; Fagundez, Carol; Grosso, Juan P; Argibay, Pablo; Arenas, Andrés; Farina, Walter M

    2016-01-01

    In eusocial insects, experiences acquired during the development have long-term consequences on mature behavior. In the honeybee that suffers profound changes associated with metamorphosis, the effect of odor experiences at larval instars on the subsequent physiological and behavioral response is still unclear. To address the impact of preimaginal experiences on the adult honeybee, colonies containing larvae were fed scented food. The effect of the preimaginal experiences with the food odor was assessed in learning performance, memory retention and generalization in 3-5- and 17-19 day-old bees, in the regulation of their expression of synaptic-related genes and in the perception and morphology of their antennae. Three-five day old bees that experienced 1-hexanol (1-HEX) as food scent responded more to the presentation of the odor during the 1-HEX conditioning than control bees (i.e., bees reared in colonies fed unscented food). Higher levels of proboscis extension response (PER) to 1-HEX in this group also extended to HEXA, the most perceptually similar odor to the experienced one that we tested. These results were not observed for the group tested at older ages. In the brain of young adults, larval experiences triggered similar levels of neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have been involved in synaptic formation after associative learning. At the sensory periphery, the experience did not alter the number of the olfactory sensilla placoidea, but did reduce the electrical response of the antennae to the experienced and novel odor. Our study provides a new insight into the effects of preimaginal experiences in the honeybee and the mechanisms underlying olfactory plasticity at larval stage of holometabolous insects. PMID:27375445

  19. Distinct Neural Mechanisms Mediate Olfactory Memory Formation at Different Timescales

    ERIC Educational Resources Information Center

    McNamara, Ann Marie; Magidson, Phillip D.; Linster, Christiane; Wilson, Donald A.; Cleland, Thomas A.

    2008-01-01

    Habituation is one of the oldest forms of learning, broadly expressed across sensory systems and taxa. Here, we demonstrate that olfactory habituation induced at different timescales (comprising different odor exposure and intertrial interval durations) is mediated by different neural mechanisms. First, the persistence of habituation memory is…

  20. Performance enhancement at the cost of potential brain plasticity: neural ramifications of nootropic drugs in the healthy developing brain

    PubMed Central

    Urban, Kimberly R.; Gao, Wen-Jun

    2014-01-01

    Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate (MPH), amphetamine), but wakefulness-promoting agents (modafinil) and glutamate activators (ampakine) are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits—dopamine, glutamate (neuronal excitation), and/or norepinephrine—stand to improve brain function in healthy individuals beyond their baseline functioning. In particular, non-medical use of prescription stimulants such as MPH and illicit use of psychostimulants for cognitive enhancement have seen a recent rise among teens and young adults in schools and college campuses. However, this enhancement likely comes with a neuronal, as well as ethical, cost. Altering glutamate function via the use of psychostimulants may impair behavioral flexibility, leading to the development and/or potentiation of addictive behaviors. Furthermore, dopamine and norepinephrine do not display linear effects; instead, their modulation of cognitive and neuronal function maps on an inverted-U curve. Healthy individuals run the risk of pushing themselves beyond optimal levels into hyperdopaminergic and hypernoradrenergic states, thus vitiating the very behaviors they are striving to improve. Finally, recent studies have begun to highlight potential damaging effects of stimulant exposure in healthy juveniles. This review explains how the main classes of cognitive enhancing drugs affect the learning and memory circuits, and highlights the potential risks and concerns in healthy individuals, particularly juveniles and adolescents. We emphasize the performance enhancement at the potential cost of brain plasticity that is associated with the neural ramifications of nootropic drugs in the healthy developing brain. PMID:24860437

  1. Temporal entrainment of cognitive functions: musical mnemonics induce brain plasticity and oscillatory synchrony in neural networks underlying memory.

    PubMed

    Thaut, Michael H; Peterson, David A; McIntosh, Gerald C

    2005-12-01

    In a series of experiments, we have begun to investigate the effect of music as a mnemonic device on learning and memory and the underlying plasticity of oscillatory neural networks. We used verbal learning and memory tests (standardized word lists, AVLT) in conjunction with electroencephalographic analysis to determine differences between verbal learning in either a spoken or musical (verbal materials as song lyrics) modality. In healthy adults, learning in both the spoken and music condition was associated with significant increases in oscillatory synchrony across all frequency bands. A significant difference between the spoken and music condition emerged in the cortical topography of the learning-related synchronization. When using EEG measures as predictors during learning for subsequent successful memory recall, significantly increased coherence (phase-locked synchronization) within and between oscillatory brain networks emerged for music in alpha and gamma bands. In a similar study with multiple sclerosis patients, superior learning and memory was shown in the music condition when controlled for word order recall, and subjects were instructed to sing back the word lists. Also, the music condition was associated with a significant power increase in the low-alpha band in bilateral frontal networks, indicating increased neuronal synchronization. Musical learning may access compensatory pathways for memory functions during compromised PFC functions associated with learning and recall. Music learning may also confer a neurophysiological advantage through the stronger synchronization of the neuronal cell assemblies underlying verbal learning and memory. Collectively our data provide evidence that melodic-rhythmic templates as temporal structures in music may drive internal rhythm formation in recurrent cortical networks involved in learning and memory.

  2. Differential Role of Inhibition in Habituation of Two Independent Afferent Pathways to a Common Motor Output

    ERIC Educational Resources Information Center

    Bristol, Adam S.; Carew, Thomas J.

    2005-01-01

    Many studies of the neural mechanisms of learning have focused on habituation, a simple form of learning in which a response decrements with repeated stimulation. In the siphon-elicited siphon withdrawal reflex (S-SWR) of the marine mollusk "Aplysia," the prevailing view is that homosynaptic depression of primary sensory afferents underlies…

  3. Early cell-wall modifications of maize cell cultures during habituation to dichlobenil.

    PubMed

    de Castro, María; Largo-Gosens, Asier; Alvarez, Jesús Miguel; García-Angulo, Penélope; Acebes, José Luis

    2014-01-15

    Studies involving the habituation of plant cell cultures to cellulose biosynthesis inhibitors have achieved significant progress as regards understanding the structural plasticity of cell walls. However, since habituation studies have typically used high concentrations of inhibitors and long-term habituation periods, information on initial changes associated with habituation has usually been lost. This study focuses on monitoring and characterizing the short-term habituation process of maize (Zea mays) cell suspensions to dichlobenil (DCB). Cellulose quantification and FTIR spectroscopy of cell walls from 20 cell lines obtained during an incipient DCB-habituation process showed a reduction in cellulose levels which tended to revert depending on the inhibitor concentration and the length of time that cells were in contact with it. Variations in the cellulose content were concomitant with changes in the expression of several ZmCesA genes, mainly involving overexpression of ZmCesA7 and ZmCesA8. In order to explore these changes in more depth, a cell line habituated to 1.5μM DCB was identified as representative of incipient DCB habituation and selected for further analysis. The cells of this habituated cell line grew more slowly and formed larger clusters. Their cell walls were modified, showing a 33% reduction in cellulose content, that was mainly counteracted by an increase in arabinoxylans, which presented increased extractability. This result was confirmed by immunodot assays graphically plotted by heatmaps, since habituated cell walls had a more extensive presence of epitopes for arabinoxylans and xylans, but also for homogalacturonan with a low degree of esterification and for galactan side chains of rhamnogalacturonan I. Furthermore, a partial shift of xyloglucan epitopes toward more easily extractable fractions was found. However, other epitopes, such as these specific for arabinan side chains of rhamnogalacturonan I or homogalacturonan with a high degree of

  4. Impaired Visual Habituation in Adults with ADHD

    ERIC Educational Resources Information Center

    Massa, Jacqueline; O'Desky, Ilyse H.

    2012-01-01

    Objective: Habituation has an important role in attention. By reducing one's sensitivity to a constant source of stimulation, it frees up attention resources to process new distinct items. Impaired habituation may disrupt sustained attention via inability to modulate the repeated intrusion of irrelevant stimuli. Method: Using Troxler fading, this…

  5. Habituation Revisited: An Updated and Revised Description of the Behavioral Characteristics of Habituation

    PubMed Central

    Rankin, Catharine H.; Abrams, Thomas; Barry, Robert J.; Bhatnagar, Seema; Clayton, David; Colombo, John; Coppola, Gianluca; Geyer, Mark A.; Glanzman, David L.; Marsland, Stephen; McSweeney, Frances; Wilson, Donald A.; Wu, Chun-Fang; Thompson, Richard F.

    2009-01-01

    The most commonly cited descriptions of the behavioral characteristics of habituation come from two papers published almost 40 years ago (Thompson and Spencer, 1966; Groves and Thompson, 1970). In August 2007, the authors of this review, who study habituation in a wide range of species and paradigms, met to discuss their work on habituation and to revisit and refine the characteristics of habituation. This review offers a re-evaluation of the characteristics of habituation in light of these discussions. We made substantial changes to only a few of the characteristics, usually to add new information and expand upon the description rather than to substantially alter the original point. PMID:18854219

  6. Shift from goal-directed to habitual cocaine seeking after prolonged experience in rats.

    PubMed

    Zapata, Agustin; Minney, Vicki L; Shippenberg, Toni S

    2010-11-17

    The development of drug-seeking habits is implicated in the transition from recreational drug use to addiction. Using a drug seeking/taking chained schedule of intravenous cocaine self-administration and reward devaluation methods in rats, the present studies examined whether drug seeking that is initially goal-directed becomes habitual after prolonged drug seeking and taking. Devaluation of the outcome of the drug seeking link (i.e., the drug taking link of the chained schedule) by extinction significantly decreased drug seeking indicating that behavior is goal-directed rather than habitual. With, however, more prolonged drug experience, animals transitioned to habitual cocaine seeking. Thus, in these animals, cocaine seeking was insensitive to outcome devaluation. Moreover, when the dorsolateral striatum, an area implicated in habit learning, was transiently inactivated, outcome devaluation was effective in decreasing drug seeking indicating that responding was no longer habitual but had reverted to control by the goal-directed system. These studies provide direct evidence that cocaine seeking becomes habitual with prolonged drug experience and describe a rodent model with which to study the neural mechanisms underlying the transition from goal-directed to habitual drug seeking.

  7. Habitual routines in task-performing groups

    NASA Technical Reports Server (NTRS)

    Gersick, C. J.; Hackman, J. R.

    1990-01-01

    Groups, like individuals, often develop habitual routines for dealing with frequently encountered stimuli. Although such routines are consequential for group life and work, little is known about them. This paper reconnoiters the territory of habitual behavior in groups that perform work within organizations. We offer a definition of group habits, identify their functions and dysfunctions, suggest how they develop and are maintained, and identify the circumstances when they are likely to be altered or abandoned. Throughout, we give special attention to the social nature of habitual routines in groups, to the interaction between habitual behavior and group life cycle phenomena, and to the role of the organizational context in prompting, shaping, and terminating habitual routines.

  8. Polysialic acid-neural cell adhesion molecule in brain plasticity: from synapses to integration of new neurons.

    PubMed

    Gascon, Eduardo; Vutskits, Laszlo; Kiss, Jozsef Zoltan

    2007-11-01

    Isoforms of the neuronal cell adhesion molecule (NCAM) carrying the linear homopolymer of alpha 2,8-linked sialic acid (polysialic acid, PSA) have emerged as particularly attractive candidates for promoting plasticity in the nervous system. The large negatively charged PSA chain of NCAM is postulated to be a spacer that reduces adhesion forces between cells allowing dynamic changes in membrane contacts. Accumulating evidence also suggests that PSA-NCAM-mediated interactions lead to activation of intracellular signaling cascades that are fundamental to the biological functions of the molecule. An important role of PSA-NCAM appears to be during development, when its expression level is high and where it contributes to the regulation of cell shape, growth or migration. However, PSA-NCAM does persist in adult brain structures such as the hippocampus that display a high degree of plasticity where it is involved in activity-induced synaptic plasticity. Recent advances in the field of PSA-NCAM research have not only consolidated the importance of this molecule in plasticity processes but also suggest a role for PSA-NCAM in the regulation of higher cognitive functions and psychiatric disorders. In this review, we discuss the role and mode of actions of PSA-NCAM in structural plasticity as well as its potential link to cognitive processes.

  9. Therapeutic Process During Exposure: Habituation Model

    PubMed Central

    Benito, Kristen G.; Walther, Michael

    2015-01-01

    The current paper outlines the habituation model of exposure process, which is a behavioral model emphasizing use of individually tailored functional analysis during exposures. This is a model of therapeutic process rather than one meant to explain the mechanism of change underlying exposure-based treatments. Habitation, or a natural decrease in anxiety level in the absence of anxiety-reducing behavior, might be best understood as an intermediate treatment outcome that informs therapeutic process, rather than as a mechanism of change. The habituation model purports that three conditions are necessary for optimal benefit from exposures: 1) fear activation, 2) minimization of anxiety-reducing behaviors, and 3) habituation. We describe prescribed therapist and client behaviors as those that increase or maintain anxiety level during an exposure (and therefore, facilitate habituation), and proscribed therapist and client behaviors as those that decrease anxiety during an exposure (and therefore, impede habituation). We illustrate model-consistent behaviors in the case of Monica, as well as outline the existing research support and call for additional research to further test the tenets of the habituation model as described in this paper. PMID:26258012

  10. Habituation as a determinant of human food intake

    PubMed Central

    Epstein, Leonard H.; Temple, Jennifer L.; Roemmich, James N.; Bouton, Mark E.

    2009-01-01

    Research has shown that animals and humans habituate on a variety of behavioral and physiological responses to repeated presentations of food cues, and habituation is related to amount of food consumed and cessation of eating. The purpose of this article is to provide an overview of experimental paradigms used to study habituation, integrate a theoretical approach to habituation to food based on memory and associative conditioning models, and review research on factors that influence habituation. Individual differences in habituation as they related to obesity and eating disorders are reviewed, along with research on how individual differences in memory can influence habituation. Other associative conditioning approaches to ingestive behavior are reviewed, as well as how habituation provides novel approaches to preventing or treating obesity. Finally, new directions for habituation research are presented. Habituation provides a novel theoretical framework from which to understand factors that regulate ingestive behavior. PMID:19348547

  11. Habituation as a determinant of human food intake.

    PubMed

    Epstein, Leonard H; Temple, Jennifer L; Roemmich, James N; Bouton, Mark E

    2009-04-01

    Research has shown that animals and humans habituate on a variety of behavioral and physiological responses to repeated presentations of food cues, and habituation is related to amount of food consumed and cessation of eating. The purpose of this article is to provide an overview of experimental paradigms used to study habituation, integrate a theoretical approach to habituation to food based on memory and associative conditioning models, and review research on factors that influence habituation. Individual differences in habituation as they relate to obesity and eating disorders are reviewed, along with research on how individual differences in memory can influence habituation. Other associative conditioning approaches to ingestive behavior are reviewed, as well as how habituation provides novel approaches to preventing or treating obesity. Finally, new directions for habituation research are presented. Habituation provides a novel theoretical framework from which to understand factors that regulate ingestive behavior.

  12. Disease duration of episodic migraine correlates with modified amplitudes and habituation of contingent negative variation.

    PubMed

    Kropp, Peter; Wallasch, Thomas-Martin; Müller, Britta; Meyer, Bianca; Darabaneanu, Stephanie; Bosse, Christoph; Keller, Armin; Meyer, Wolfgang; Gerber, Wolf-Dieter

    2015-06-01

    Cortical habituation in episodic migraine patients without medication overuse headache (MOH), recorded by contingent negative variation (CNV), is often reduced compared with healthy controls. There is evidence that with longer duration of migraine disease (DOD) amplitudes and habituation of CNV become progressively abnormal. The aim of the study was to examine habituation characteristics of contingent negative variation in episodic migraine patients suffering from short- and long-lasting migraine compared to matched healthy controls. 32 migraine patients without aura and without MOH diagnosed according to the revised ICHD-II criteria and 16 age- and sex-matched healthy controls were included. According to DOD, the total sample of migraine patients was divided into two groups (group a: DOD <121 months, n = 17 subjects, group b: DOD >120 months, n = 15 subjects). Both migraine groups did not differ in the number of days of migraine and the duration of attacks. Overall CNV and initial CNV differed significantly between migraine patients and controls, whereas the former produced more negative amplitudes. In the migraine group lack of or deficient habituation occurred, whilst controls showed habituation. There were middle range correlations between the DOD and overall CNV, initial CNV, and y-intercept. Patients suffering from long-lasting migraine produced higher CNV amplitudes with a higher y-intercept. The results are interpreted as "maladaptive plasticity" with a risen intercept in long-lasting migraine. PMID:25432434

  13. The first juvenile specimens of Plateosaurus engelhardti from Frick, Switzerland: isolated neural arches and their implications for developmental plasticity in a basal sauropodomorph

    PubMed Central

    Sander, P. Martin

    2014-01-01

    The dinosaur Plateosaurus engelhardti is the most abundant dinosaur in the Late Triassic of Europe and the best known basal sauropodomorph. Plateosaurus engelhardti was one of the first sauropodomorph dinosaurs to display a large body size. Remains can be found in the Norian stage of the Late Triassic in over 40 localities in Central Europe (France, Germany, and Switzerland) and in Greenland. Since the first discovery of P. engelhardti no juvenile specimens of this species had been described in detail. Here we describe the first remains of juvenile individuals, isolated cervical and dorsal neural arches from Switzerland. These were separated postmortem from their respective centra because of unfused neurocentral sutures. However the specimens share the same neural arch morphology found in adults. Morphometric analysis suggests body lengths of the juvenile individuals that is greater than those of most adult specimens. This supports the hypothesis of developmental plasticity in Plateosaurus engelhardti that previously had been based on histological data only. Alternative hypotheses for explaining the poor correlation between ontogenetic stage and size in this taxon are multiple species or sexual morphs with little morphological variance or time-averaging of individuals from populations differing in body size. PMID:25071987

  14. Synergistic effects of transplanted adult neural stem/progenitor cells, chondroitinase, and growth factors promote functional repair and plasticity of the chronically injured spinal cord.

    PubMed

    Karimi-Abdolrezaee, Soheila; Eftekharpour, Eftekhar; Wang, Jian; Schut, Desiree; Fehlings, Michael G

    2010-02-01

    The transplantation of neural stem/progenitor cells (NPCs) is a promising therapeutic strategy for spinal cord injury (SCI). However, to date NPC transplantation has exhibited only limited success in the treatment of chronic SCI. Here, we show that chondroitin sulfate proteoglycans (CSPGs) in the glial scar around the site of chronic SCI negatively influence the long-term survival and integration of transplanted NPCs and their therapeutic potential for promoting functional repair and plasticity. We targeted CSPGs in the chronically injured spinal cord by sustained infusion of chondroitinase ABC (ChABC). One week later, the same rats were treated with transplants of NPCs and transient infusion of growth factors, EGF, bFGF, and PDGF-AA. We demonstrate that perturbing CSPGs dramatically optimizes NPC transplantation in chronic SCI. Engrafted NPCs successfully integrate and extensively migrate within the host spinal cord and principally differentiate into oligodendrocytes. Furthermore, this combined strategy promoted the axonal integrity and plasticity of the corticospinal tract and enhanced the plasticity of descending serotonergic pathways. These neuroanatomical changes were also associated with significantly improved neurobehavioral recovery after chronic SCI. Importantly, this strategy did not enhance the aberrant synaptic connectivity of pain afferents, nor did it exacerbate posttraumatic neuropathic pain. For the first time, we demonstrate key biological and functional benefits for the combined use of ChABC, growth factors, and NPCs to repair the chronically injured spinal cord. These findings could potentially bring us closer to the application of NPCs for patients suffering from chronic SCI or other conditions characterized by the formation of a glial scar.

  15. Corticostriatal circuitry and habitual ethanol seeking.

    PubMed

    Barker, Jacqueline M; Corbit, Laura H; Robinson, Donita L; Gremel, Christina M; Gonzales, Rueben A; Chandler, L Judson

    2015-12-01

    The development of alcohol-use disorders is thought to involve a transition from casual alcohol use to uncontrolled alcohol-seeking behavior. This review will highlight evidence suggesting that the shift toward inflexible alcohol seeking that occurs across the development of addiction consists, in part, of a progression from goal-directed to habitual behaviors. This shift in "response strategy" is thought to be largely regulated by corticostriatal network activity. Indeed, specific neuroanatomical substrates within the prefrontal cortex and the striatum have been identified as playing opposing roles in the expression of actions and habits. A majority of the research on the neurobiology of habitual behavior has focused on non-drug reward seeking. Here, we will highlight recent research identifying corticostriatal structures that regulate the expression of habitual alcohol seeking and a comparison will be made when possible to findings for non-drug rewards.

  16. Habitual control of goal selection in humans

    PubMed Central

    Cushman, Fiery; Morris, Adam

    2015-01-01

    Humans choose actions based on both habit and planning. Habitual control is computationally frugal but adapts slowly to novel circumstances, whereas planning is computationally expensive but can adapt swiftly. Current research emphasizes the competition between habits and plans for behavioral control, yet many complex tasks instead favor their integration. We consider a hierarchical architecture that exploits the computational efficiency of habitual control to select goals while preserving the flexibility of planning to achieve those goals. We formalize this mechanism in a reinforcement learning setting, illustrate its costs and benefits, and experimentally demonstrate its spontaneous application in a sequential decision-making task. PMID:26460050

  17. Habitual control of goal selection in humans.

    PubMed

    Cushman, Fiery; Morris, Adam

    2015-11-10

    Humans choose actions based on both habit and planning. Habitual control is computationally frugal but adapts slowly to novel circumstances, whereas planning is computationally expensive but can adapt swiftly. Current research emphasizes the competition between habits and plans for behavioral control, yet many complex tasks instead favor their integration. We consider a hierarchical architecture that exploits the computational efficiency of habitual control to select goals while preserving the flexibility of planning to achieve those goals. We formalize this mechanism in a reinforcement learning setting, illustrate its costs and benefits, and experimentally demonstrate its spontaneous application in a sequential decision-making task. PMID:26460050

  18. [Therapeutic management of habitual body language].

    PubMed

    Herdieckerhoff, G

    1986-01-01

    Habitual nonverbal behavior introduces the therapist to at times intense counter-transference reactions. The therapist becomes a participant to early object relations. If you succeed in concentrating the attention onto the interactional process you will observe, which signal system triggers the counter-transference reactions. If this system of signals is expressed by the patient in response to a situation or verbalized, the therapist can respond to the concurrent behavior. Counter-transference relations become clear and early (often preverbal) object-relations can be reconstructed. Habitual nonverbal behavior occurs when object-relations are either lacking ore obstrusive. PMID:3716655

  19. The pregnane xenobiotic receptor, a prominent liver factor, has actions in the midbrain for neurosteroid synthesis and behavioral/neural plasticity of female rats

    PubMed Central

    Frye, Cheryl A.; Koonce, Carolyn J.; Walf, Alicia A.

    2014-01-01

    A novel factor of interest for growth/plasticity in the brain is pregnane xenobiotic receptor (PXR). PXR is a liver factor known for its role in xenobiotic clearance and cholesterol metabolism. It is expressed in the brain, suggesting a potential role for plasticity, particularly involving cholesterol-based steroids and neurosteroids. Mating induces synthesis of neurosteroids in the midbrain Ventral Tegmental Area (VTA) of female rodents, as well as other “plastic” regions of the brain, including the hippocampus, that may be involved in the consolidation of the mating experience. Reducing PXR in the VTA attenuates mating-induced biosynthesis of the neurosteroid, 5α-pregnan-3α-ol-20-one (3α,5α-THP). The 18 kDA translocator protein (TSPO) is one rate-limiting factor for 3α,5α-THP neurosteroidogenesis. The hypothesis tested was that PXR is an upstream factor of TSPO for neurosteroidogenesis of 3α,5α-THP in the VTA for lordosis, independent of peripheral glands. First, proestrous rats were administered a TSPO blocker (PK11195) and/or 3α,5α-THP following infusions of PXR antisense oligonucleotides (AS-ODNs) or vehicle to the VTA. Inhibiting TSPO with PK11195 reduced 3α,5α-THP levels in the midbrain and lordosis, an effect that could be reversed with 3α,5α-THP administration, but not AS-ODN+3α,5α-THP. Second, proestrous, ovariectomized (OVX), or ovariectomized/adrenalectomized (OVX/ADX) rats were infused with a TSPO enhancer (FGIN 1-27) subsequent to AS-ODNs or vehicle to the VTA. PXR AS-ODNs blocked actions of FGIN 1–27 for lordosis and 3α,5α-THP levels among proestrous > OVX > OVX/ADX rats. Thus, PXR may be upstream of TSPO, involved in neurosteroidogenesis of 3α,5α-THP in the brain for plasticity. This novel finding of a liver factor involved in behavioral/neural plasticity substantiates future studies investigating factors known for their prominent actions in the peripheral organs, such as the liver, for modulating brain function and its

  20. Hormone-dependent neural plasticity in the juvenile and adult song system: what makes a successful male?

    PubMed

    Gahr, Manfred

    2004-06-01

    The sexual quality of adult song is the result of genetic and epigenetic mechanisms shaping the neural song system throughout life. Genetic brain-intrinsic mechanisms determine the neuron pools that develop into forebrain song control areas independent of gonadal steroid hormones, androgens and estrogens. One fate of these neurons is the potential to express sex steroid receptors, such as androgen and estrogen receptors. Genetic brain-intrinsic mechanisms, too, determine the activity of hypothalamic-pituitary-gonad (HPG) axis, i.e., the working range and responsiveness of HPG axis to produce gonadal hormones. The epigenetic action of gonadal steroid hormones (androgens and estrogens) on determined vocal neurons is required to maintain and increase the pool of determined vocal neurons and to complete the connections of the vocal system, i.e., to make it function motorically. The subsequent influence of environmental information, including both external (socio-sexual and physical) and internal (body physiology) signals, specify the further neural phenotype of vocal areas either through acting on the HPG axis and differential release of gonadal hormones or through non-gonadal hormone systems, both of which have target neurons in the functional vocal system. Despite the clear evidence of hormone dependency of the development of both the adult song phenotype and song system phenotype, their causal relation is complex.

  1. Habituation to a stressor predicts adolescents' adiposity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background and Objectives: Stress is associated with gains in adiposity. One factor that determines how much stress is experienced is how quickly an adolescent reduces responding (habituates) across repeated stressors. The purpose of this study was to determine the association of body mass index pe...

  2. Reading in the dark: neural correlates and cross-modal plasticity for learning to read entire words without visual experience.

    PubMed

    Sigalov, Nadine; Maidenbaum, Shachar; Amedi, Amir

    2016-03-01

    Cognitive neuroscience has long attempted to determine the ways in which cortical selectivity develops, and the impact of nature vs. nurture on it. Congenital blindness (CB) offers a unique opportunity to test this question as the brains of blind individuals develop without visual experience. Here we approach this question through the reading network. Several areas in the visual cortex have been implicated as part of the reading network, and one of the main ones among them is the VWFA, which is selective to the form of letters and words. But what happens in the CB brain? On the one hand, it has been shown that cross-modal plasticity leads to the recruitment of occipital areas, including the VWFA, for linguistic tasks. On the other hand, we have recently demonstrated VWFA activity for letters in contrast to other visual categories when the information is provided via other senses such as touch or audition. Which of these tasks is more dominant? By which mechanism does the CB brain process reading? Using fMRI and visual-to-auditory sensory substitution which transfers the topographical features of the letters we compare reading with semantic and scrambled conditions in a group of CB. We found activation in early auditory and visual cortices during the early processing phase (letter), while the later phase (word) showed VWFA and bilateral dorsal-intraparietal activations for words. This further supports the notion that many visual regions in general, even early visual areas, also maintain a predilection for task processing even when the modality is variable and in spite of putative lifelong linguistic cross-modal plasticity. Furthermore, we find that the VWFA is recruited preferentially for letter and word form, while it was not recruited, and even exhibited deactivation, for an immediately subsequent semantic task suggesting that despite only short sensory substitution experience orthographic task processing can dominate semantic processing in the VWFA. On a wider

  3. Reading in the dark: neural correlates and cross-modal plasticity for learning to read entire words without visual experience.

    PubMed

    Sigalov, Nadine; Maidenbaum, Shachar; Amedi, Amir

    2016-03-01

    Cognitive neuroscience has long attempted to determine the ways in which cortical selectivity develops, and the impact of nature vs. nurture on it. Congenital blindness (CB) offers a unique opportunity to test this question as the brains of blind individuals develop without visual experience. Here we approach this question through the reading network. Several areas in the visual cortex have been implicated as part of the reading network, and one of the main ones among them is the VWFA, which is selective to the form of letters and words. But what happens in the CB brain? On the one hand, it has been shown that cross-modal plasticity leads to the recruitment of occipital areas, including the VWFA, for linguistic tasks. On the other hand, we have recently demonstrated VWFA activity for letters in contrast to other visual categories when the information is provided via other senses such as touch or audition. Which of these tasks is more dominant? By which mechanism does the CB brain process reading? Using fMRI and visual-to-auditory sensory substitution which transfers the topographical features of the letters we compare reading with semantic and scrambled conditions in a group of CB. We found activation in early auditory and visual cortices during the early processing phase (letter), while the later phase (word) showed VWFA and bilateral dorsal-intraparietal activations for words. This further supports the notion that many visual regions in general, even early visual areas, also maintain a predilection for task processing even when the modality is variable and in spite of putative lifelong linguistic cross-modal plasticity. Furthermore, we find that the VWFA is recruited preferentially for letter and word form, while it was not recruited, and even exhibited deactivation, for an immediately subsequent semantic task suggesting that despite only short sensory substitution experience orthographic task processing can dominate semantic processing in the VWFA. On a wider

  4. Natural and Drug Rewards Act on Common Neural Plasticity Mechanisms with ΔFosB as a Key Mediator

    PubMed Central

    Pitchers, Kyle K.; Vialou, Vincent; Nestler, Eric J.; Laviolette, Steven R.; Lehman, Michael N.

    2013-01-01

    Drugs of abuse induce neuroplasticity in the natural reward pathway, specifically the nucleus accumbens (NAc), thereby causing development and expression of addictive behavior. Recent evidence suggests that natural rewards may cause similar changes in the NAc, suggesting that drugs may activate mechanisms of plasticity shared with natural rewards, and allowing for unique interplay between natural and drug rewards. In this study, we demonstrate that sexual experience in male rats when followed by short or prolonged periods of loss of sex reward causes enhanced amphetamine reward, indicated by sensitized conditioned place preference for low-dose (0.5 mg/kg) amphetamine. Moreover, the onset, but not the longer-term expression, of enhanced amphetamine reward was correlated with a transient increase in dendritic spines in the NAc. Next, a critical role for the transcription factor ΔFosB in sex experience-induced enhanced amphetamine reward and associated increases in dendritic spines on NAc neurons was established using viral vector gene transfer of the dominant-negative binding partner ΔJunD. Moreover, it was demonstrated that sexual experience-induced enhanced drug reward, ΔFosB, and spinogenesis are dependent on mating-induced dopamine D1 receptor activation in the NAc. Pharmacological blockade of D1 receptor, but not D2 receptor, in the NAc during sexual behavior attenuated ΔFosB induction and prevented increased spinogenesis and sensitized amphetamine reward. Together, these findings demonstrate that drugs of abuse and natural reward behaviors act on common molecular and cellular mechanisms of plasticity that control vulnerability to drug addiction, and that this increased vulnerability is mediated by ΔFosB and its downstream transcriptional targets. PMID:23426671

  5. High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids

    PubMed Central

    Peirouvi, T.; Yekani, F.; Azarnia, M.; Massumi, M.

    2015-01-01

    Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment. PMID:27175157

  6. Cortical plasticity and rehabilitation.

    PubMed

    Moucha, Raluca; Kilgard, Michael P

    2006-01-01

    The brain is constantly adapting to environmental and endogenous changes (including injury) that occur at every stage of life. The mechanisms that regulate neural plasticity have been refined over millions of years. Motivation and sensory experience directly shape the rewiring that makes learning and neurological recovery possible. Guiding neural reorganization in a manner that facilitates recovery of function is a primary goal of neurological rehabilitation. As the rules that govern neural plasticity become better understood, it will be possible to manipulate the sensory and motor experience of patients to induce specific forms of plasticity. This review summarizes our current knowledge regarding factors that regulate cortical plasticity, illustrates specific forms of reorganization induced by control of each factor, and suggests how to exploit these factors for clinical benefit.

  7. Effects of the hallucinogen psilocybin on habituation and prepulse inhibition of the startle reflex in humans.

    PubMed

    Gouzoulis-Mayfrank, E; Heekeren, K; Thelen, B; Lindenblatt, H; Kovar, K A; Sass, H; Geyer, M A

    1998-11-01

    Schizophrenic patients exhibit deficits in indices of sensorimotor gating, such as habituation and prepulse inhibition (PPI) of the startle reflex. Hallucinogenic drug-induced states are putative models for the early and acute stages of schizophrenic and schizophrenia-spectrum disorders. Hallucinogenic drugs have been shown to disrupt PPI and/or retard habituation of the startle reflex in animal models of schizophrenia, consistent with the view of hallucinogen-induced states as 'model psychoses'. We evaluated the effects of the hallucinogen psilocybin on PPI and habituation of the startle reflex in a double-blind, placebo-controlled human study with 12 healthy subjects. In contrast to animal studies, in our small human sample, psilocybin increased PPI, while having no clear effect on habituation (n = 6). These findings must be considered preliminary because several factors, including dose regimens and experimental parameters, may influence the results of studies on startle plasticity. Further investigations both with psychotic patients in different stages of the disease and with human and animal models of schizophrenia are needed in order to explore the effects of hallucinogens on sensorimotor gating and the relationship between information processing in hallucinogenic drug-induced states and the naturally occurring psychoses.

  8. Habituation of Backward Escape Swimming in the Marbled Crayfish.

    PubMed

    Kasuya, Azusa; Nagayama, Toshiki

    2016-02-01

    In the present study, we performed behavioral analyses of the habituation of backward escape swimming in the marbled crayfish, Procambarus fallax. Application of rapid mechanical stimulation to the rostrum elicited backward swimming following rapid abdominal flexion of crayfish. Response latency was very short-tens of msec-suggesting that backward swimming is mediated by MG neurons. When stimulation was repeated with 10 sec interstimulus intervals the MG-like tailflip did not occur, as the animals showed habituation. Retention of habituation was rather short, with most animals recovering from habituation within 10 min. Previous experience of habituation was remembered and animals habituated faster during a second series of experiments with similar repetitive stimuli. About half the number of stimulus trials was necessary to habituate in the second test compared to the first test. This promotion of habituation was observed in animals with delay periods of rest within 60 min following the first habituation. After 90 min of rest from the first habitation, animals showed a similar time course for the second habituation. With five stimuli at 15 min interval during 90 min of the rest, trained animals showed rapid habituation, indicating reinforcement of the memory of previous experiments. Crayfish also showed dishabituation when mechanical stimulation was applied to the tail following habituation.

  9. Habituation as a Determinant of Human Food Intake

    ERIC Educational Resources Information Center

    Epstein, Leonard H.; Temple, Jennifer L.; Roemmich, James N.; Bouton, Mark E.

    2009-01-01

    Research has shown that animals and humans habituate on a variety of behavioral and physiological responses to repeated presentations of food cues, and habituation is related to amount of food consumed and cessation of eating. The purpose of this article is to provide an overview of experimental paradigms used to study habituation, integrate a…

  10. Habituation of Backward Escape Swimming in the Marbled Crayfish.

    PubMed

    Kasuya, Azusa; Nagayama, Toshiki

    2016-02-01

    In the present study, we performed behavioral analyses of the habituation of backward escape swimming in the marbled crayfish, Procambarus fallax. Application of rapid mechanical stimulation to the rostrum elicited backward swimming following rapid abdominal flexion of crayfish. Response latency was very short-tens of msec-suggesting that backward swimming is mediated by MG neurons. When stimulation was repeated with 10 sec interstimulus intervals the MG-like tailflip did not occur, as the animals showed habituation. Retention of habituation was rather short, with most animals recovering from habituation within 10 min. Previous experience of habituation was remembered and animals habituated faster during a second series of experiments with similar repetitive stimuli. About half the number of stimulus trials was necessary to habituate in the second test compared to the first test. This promotion of habituation was observed in animals with delay periods of rest within 60 min following the first habituation. After 90 min of rest from the first habitation, animals showed a similar time course for the second habituation. With five stimuli at 15 min interval during 90 min of the rest, trained animals showed rapid habituation, indicating reinforcement of the memory of previous experiments. Crayfish also showed dishabituation when mechanical stimulation was applied to the tail following habituation. PMID:26853863

  11. Fetal Habituation Performance: Gestational Age and Sex Effects

    ERIC Educational Resources Information Center

    McCorry, Noleen K.; Hepper, Peter G.

    2007-01-01

    Habituation is the decrement in response to repeated stimulation. Fetal habituation performance may reflect the functioning of the central nervous system (CNS) prenatally. However, basic characteristics of the prenatal habituation phenomena remain unclear, such as the relationship with gestational age (GA) and fetal sex. The current study…

  12. 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

  13. Neural Plastic Effects of Working Memory Training Influenced by Self-perceived Stress in Stroke: A Case Illustration

    PubMed Central

    Leung, Ada W. S.; Barrett, Lauren M.; Butterworth, Darcy; Werther, Karin; Dawson, Deirdre R.; Brintnell, E. Sharon

    2016-01-01

    This case study examined the effects of auditory working memory (WM) training on neuroplastic changes in stroke survivors and how such effects might be influenced by self-perceived stress. Two participants with a history of stroke participated in the study. One of them had a higher level of self-perceived stress. Both participants underwent a course of auditory WM training and completed baseline and post-training assessments such as self-perceived stress, performance satisfaction questionnaires, behavioral task performance, and functional magnetic resonance imaging. They were trained on a computerized auditory WM task (n-back) 5 days a week for 6 weeks, for a total of 20 h. Participant 1 had high levels of perceived stress, both pre- and post-training, and showed improvement on the satisfaction aspect of functional engagement only. Participant 2 had lower levels of perceived stress and demonstrated improvements on all performance tasks. Neuroimaging results showed evidence of improved neural efficiency on the trained task for participant 2. The results shed light on the need to evaluate psychological influences, e.g., stress, when studying the neuroplastic changes in people with stroke. However, the case design approach and other factors that might have positively influenced outcomes mean that these results must be interpreted with a great deal of caution. Future studies using a larger sample are recommended to verify the findings. PMID:27625614

  14. Neural Plastic Effects of Working Memory Training Influenced by Self-perceived Stress in Stroke: A Case Illustration.

    PubMed

    Leung, Ada W S; Barrett, Lauren M; Butterworth, Darcy; Werther, Karin; Dawson, Deirdre R; Brintnell, E Sharon

    2016-01-01

    This case study examined the effects of auditory working memory (WM) training on neuroplastic changes in stroke survivors and how such effects might be influenced by self-perceived stress. Two participants with a history of stroke participated in the study. One of them had a higher level of self-perceived stress. Both participants underwent a course of auditory WM training and completed baseline and post-training assessments such as self-perceived stress, performance satisfaction questionnaires, behavioral task performance, and functional magnetic resonance imaging. They were trained on a computerized auditory WM task (n-back) 5 days a week for 6 weeks, for a total of 20 h. Participant 1 had high levels of perceived stress, both pre- and post-training, and showed improvement on the satisfaction aspect of functional engagement only. Participant 2 had lower levels of perceived stress and demonstrated improvements on all performance tasks. Neuroimaging results showed evidence of improved neural efficiency on the trained task for participant 2. The results shed light on the need to evaluate psychological influences, e.g., stress, when studying the neuroplastic changes in people with stroke. However, the case design approach and other factors that might have positively influenced outcomes mean that these results must be interpreted with a great deal of caution. Future studies using a larger sample are recommended to verify the findings.

  15. What does Neural Plasticity Tell us about Role of Primary Visual Cortex (V1) in Visual Awareness?

    PubMed

    Silvanto, Juha; Rees, Geraint

    2011-01-01

    The complete loss of visual awareness resulting from a lesion to the primary visual cortex (V1) suggests that this region is indispensable for conscious visual perception. There are however a number cases of conscious perception in the absence of V1 which appear to challenge this conclusion. These include reports of patients with bilateral V1 lesions sustained at an early age whose conscious vision has spontaneously recovered, as well as stroke patients who have recovered some conscious vision with the help of rehabilitation programs. In addition, the phenomenon of hemianopic completion and percepts induced by brain stimulation suggest that V1 may not be necessary for conscious perception in all circumstances. Furthermore, that the visual abilities in the cat are associated with the recovery of normal extrastriate tuning properties rather than emulation of V1 functions suggests that there is nothing unique about the functional properties of this region in visual awareness. Rather, the dramatic effect of a V1 lesion on visual awareness may be due to its role in providing the majority of extrastriate visual input, the loss of which abolishes normal neural responsiveness throughout the visual cortex. PMID:21713187

  16. Neural Plastic Effects of Working Memory Training Influenced by Self-perceived Stress in Stroke: A Case Illustration.

    PubMed

    Leung, Ada W S; Barrett, Lauren M; Butterworth, Darcy; Werther, Karin; Dawson, Deirdre R; Brintnell, E Sharon

    2016-01-01

    This case study examined the effects of auditory working memory (WM) training on neuroplastic changes in stroke survivors and how such effects might be influenced by self-perceived stress. Two participants with a history of stroke participated in the study. One of them had a higher level of self-perceived stress. Both participants underwent a course of auditory WM training and completed baseline and post-training assessments such as self-perceived stress, performance satisfaction questionnaires, behavioral task performance, and functional magnetic resonance imaging. They were trained on a computerized auditory WM task (n-back) 5 days a week for 6 weeks, for a total of 20 h. Participant 1 had high levels of perceived stress, both pre- and post-training, and showed improvement on the satisfaction aspect of functional engagement only. Participant 2 had lower levels of perceived stress and demonstrated improvements on all performance tasks. Neuroimaging results showed evidence of improved neural efficiency on the trained task for participant 2. The results shed light on the need to evaluate psychological influences, e.g., stress, when studying the neuroplastic changes in people with stroke. However, the case design approach and other factors that might have positively influenced outcomes mean that these results must be interpreted with a great deal of caution. Future studies using a larger sample are recommended to verify the findings. PMID:27625614

  17. Neural Plastic Effects of Working Memory Training Influenced by Self-perceived Stress in Stroke: A Case Illustration

    PubMed Central

    Leung, Ada W. S.; Barrett, Lauren M.; Butterworth, Darcy; Werther, Karin; Dawson, Deirdre R.; Brintnell, E. Sharon

    2016-01-01

    This case study examined the effects of auditory working memory (WM) training on neuroplastic changes in stroke survivors and how such effects might be influenced by self-perceived stress. Two participants with a history of stroke participated in the study. One of them had a higher level of self-perceived stress. Both participants underwent a course of auditory WM training and completed baseline and post-training assessments such as self-perceived stress, performance satisfaction questionnaires, behavioral task performance, and functional magnetic resonance imaging. They were trained on a computerized auditory WM task (n-back) 5 days a week for 6 weeks, for a total of 20 h. Participant 1 had high levels of perceived stress, both pre- and post-training, and showed improvement on the satisfaction aspect of functional engagement only. Participant 2 had lower levels of perceived stress and demonstrated improvements on all performance tasks. Neuroimaging results showed evidence of improved neural efficiency on the trained task for participant 2. The results shed light on the need to evaluate psychological influences, e.g., stress, when studying the neuroplastic changes in people with stroke. However, the case design approach and other factors that might have positively influenced outcomes mean that these results must be interpreted with a great deal of caution. Future studies using a larger sample are recommended to verify the findings.

  18. Caffeine Promotes Global Spatial Processing in Habitual and Non-Habitual Caffeine Consumers

    PubMed Central

    Giles, Grace E.; Mahoney, Caroline R.; Brunyé, Tad T.; Taylor, Holly A.; Kanarek, Robin B.

    2013-01-01

    Information processing is generally biased toward global cues, often at the expense of local information. Equivocal extant data suggests that arousal states may accentuate either a local or global processing bias, at least partially dependent on the nature of the manipulation, task, and stimuli. To further differentiate the conditions responsible for such equivocal results we varied caffeine doses to alter physiological arousal states and measured their effect on tasks requiring the retrieval of local versus global spatial knowledge. In a double-blind, repeated-measures design, non-habitual (Experiment 1; N = 36, M = 42.5 ± 28.7 mg/day caffeine) and habitual (Experiment 2; N = 34, M = 579.5 ± 311.5 mg/day caffeine) caffeine consumers completed four test sessions corresponding to each of four caffeine doses (0, 100, 200, 400 mg). During each test session, participants consumed a capsule containing one of the three doses of caffeine or placebo, waited 60 min, and then completed two spatial tasks, one involving memorizing maps and one spatial descriptions. A spatial statement verification task tested local versus global spatial knowledge by differentially probing memory for proximal versus distal landmark relationships. On the map learning task, results indicated that caffeine enhanced memory for distal (i.e., global) compared to proximal (i.e., local) comparisons at 100 (marginal), 200, and 400 mg caffeine in non-habitual consumers, and marginally beginning at 200 mg caffeine in habitual consumers. On the spatial descriptions task, caffeine enhanced memory for distal compared to proximal comparisons beginning at 100 mg in non-habitual but not habitual consumers. We thus provide evidence that caffeine-induced physiological arousal amplifies global spatial processing biases, and these effects are at least partially driven by habitual caffeine consumption. PMID:24146646

  19. Habituation and sensitization in primary headaches.

    PubMed

    Coppola, Gianluca; Di Lorenzo, Cherubino; Schoenen, Jean; Pierelli, Francesco

    2013-07-30

    The phenomena of habituation and sensitization are considered most useful for studying the neuronal substrates of information processing in the CNS. Both were studied in primary headaches, that are functional disorders of the brain characterized by an abnormal responsivity to any kind of incoming innocuous or painful stimuli and it's cycling pattern over time (interictal, pre-ictal, ictal). The present review summarizes available data on stimulus responsivity in primary headaches obtained with clinical neurophysiology. In migraine, the majority of electrophysiological studies between attacks have shown that, for a number of different sensory modalities, the brain is characterised by a lack of habituation of evoked responses to repeated stimuli. This abnormal processing of the incoming information reaches its maximum a few days before the beginning of an attack, and normalizes during the attack, at a time when sensitization may also manifest itself. An abnormal rhythmic activity between thalamus and cortex, namely thalamocortical dysrhythmia, may be the pathophysiological mechanism subtending abnormal information processing in migraine. In tension-type headache (TTH), only few signs of deficient habituation were observed only in subgroups of patients. By contrast, using grand-average responses indirect evidence for sensitization has been found in chronic TTH with increased nociceptive specific reflexes and evoked potentials. Generalized increased sensitivity to pain (lower thresholds and increased pain rating) and a dysfunction in supraspinal descending pain control systems may contribute to the development and/or maintenance of central sensitization in chronic TTH. Cluster headache patients are characterized during the bout and on the headache side by a pronounced lack of habituation of the brainstem blink reflex and a general sensitization of pain processing. A better insight into the nature of these ictal/interictal electrophysiological dysfunctions in primary

  20. Dietary Variety Impairs Habituation in Children

    PubMed Central

    Temple, Jennifer L.; Giacomelli, April M.; Roemmich, James N.; Epstein, Leonard H.

    2008-01-01

    Objective The purpose of these studies was to test the hypothesis that dietary variety decreases the rate of habituation and increases energy intake in children. Design In Experiment 1, salivation in response to the same or a variety of food cues was measured followed by consumption of the study food(s). In Experiment 2, children responded in a computer task to earn points for the same or a variety of low or high energy density foods, which were then consumed. Main Outcome Measures Salivation, number of responses, and energy intake were measured. Results Participants in the same groups habituated faster than those in the variety groups (p < .05), and in Experiment 2, the effect of variety was independent of energy density. Participants in the variety groups also consumed more energy than those in the same groups in both experiments (p < .05). Conclusions Dietary variety disrupted habituation and increased energy intake in children. In addition, the response to dietary variety was independent of energy density, suggesting that increasing variety of low energy density foods may increase consumption. PMID:18248101

  1. Alaskan brown bears, humans, and habituation

    USGS Publications Warehouse

    Smith, Thomas; Herrero, Stephen; DeBruyn, Terry D.

    2005-01-01

    We present a new paradigm for understanding habituation and the role it plays in brown bear (Ursus arctos) populations and interactions with humans in Alaska. We assert that 3 forms of habituation occur in Alaska: bear-to-bear, bear-to-human, and human-to-bear. We present data that supports our theory that bear density is an important factor influencing a bear’s overt reaction distance (ORD); that as bear density increases, overt reaction distance decreases, as does the likelihood of bear– human interactions. We maintain that the effects of bear-to-bear habituation are largely responsible for not only shaping bear aggregations but also for creating the relatively safe environment for bear viewing experienced at areas where there are high densities of brown bears. By promoting a better understanding of the forces that shape bear social interactions within populations and with humans that mingle with them, we can better manage human activities and minimize bear–human conflict.

  2. Temporomandibular Disorders: The Habitual Chewing Side Syndrome

    PubMed Central

    Santana-Mora, Urbano; López-Cedrún, José; Mora, María J.; Otero, Xosé L.; Santana-Penín, Urbano

    2013-01-01

    Background Temporomandibular disorders are the most common cause of chronic orofacial pain, but, except where they occur subsequent to trauma, their cause remains unknown. This cross-sectional study assessed chewing function (habitual chewing side) and the differences of the chewing side and condylar path and lateral anterior guidance angles in participants with chronic unilateral temporomandibular disorder. This is the preliminary report of a randomized trial that aimed to test the effect of a new occlusal adjustment therapy. Methods The masticatory function of 21 randomly selected completely dentate participants with chronic temporomandibular disorders (all but one with unilateral symptoms) was assessed by observing them eat almonds, inspecting the lateral horizontal movement of the jaw, with kinesiography, and by means of interview. The condylar path in the sagittal plane and the lateral anterior guidance angles with respect to the Frankfort horizontal plane in the frontal plane were measured on both sides in each individual. Results Sixteen of 20 participants with unilateral symptoms chewed on the affected side; the concordance (Fisher’s exact test, P = .003) and the concordance-symmetry level (Kappa coefficient κ = 0.689; 95% confidence interval [CI], 0.38 to 0.99; P = .002) were significant. The mean condylar path angle was steeper (53.47(10.88) degrees versus 46.16(7.25) degrees; P = .001), and the mean lateral anterior guidance angle was flatter (41.63(13.35) degrees versus 48.32(9.53) degrees P = .036) on the symptomatic side. Discussion The results of this study support the use of a new term based on etiology, “habitual chewing side syndrome”, instead of the nonspecific symptom-based “temporomandibular joint disorders”; this denomination is characterized in adults by a steeper condylar path, flatter lateral anterior guidance, and habitual chewing on the symptomatic side. PMID:23593156

  3. Heterosynaptic facilitation of tail sensory neuron synaptic transmission during habituation in tail-induced tail and siphon withdrawal reflexes of Aplysia.

    PubMed

    Stopfer, M; Carew, T J

    1996-08-15

    In cellular studies of habituation, such as in the gill and siphon withdrawal reflex to tactile stimulation of the siphon of Aplysia, a mechanism that has emerged as an explanation for response decrement during habituation is homosynaptic depression at sensory neurons mediating the behavioral response. We have examined the contribution of homosynaptic depression to habituation in sensory neurons that contribute to two reflex behaviors in Aplysia, tail withdrawal and siphon withdrawal, both elicited by threshold-level tail stimulation. In a companion paper (this issue), we reported that repeated tail stimulation, identical to that producing habituation in siphon withdrawal in freely moving animals, also produces habituation in reduced preparations. In this paper, we extend these behavioral findings by showing that in reduced preparations, identical tail stimulation also produces habituation of the tail withdrawal reflex. In addition, our cellular experiments show that (1) identified sensory and motor neurons in both reflex systems respond to identical repeated tail stimulation; in sensory neurons it produces a progressive decrease in spike number and increase in spike latency, and in motor neurons it produces progressive decrement in complex EPSPs and spike output. (2) Homosynaptic depression of the tail sensory neuron to tail motor neuron synapse does occur when the sensory neurons are activated repetitively by intracellular current. (3) Homosynaptic depression at this synapse does not occur when the sensory neurons are activated repetitively by threshold-level tail stimuli that elicit the behavioral reflex and cause habituation; rather, the sensory neurons exhibit significant heterosynaptic facilitation. Thus, in these reflexes, habituation is not accompanied by homosynaptic depression at the sensory neurons, suggesting that the plasticity underlying habituation occurs primarily at interneuronal sites.

  4. The Habituation/Cross-Habituation Test Revisited: Guidance from Sniffing and Video Tracking

    PubMed Central

    Coronas-Samano, G.; Ivanova, A. V.

    2016-01-01

    The habituation/cross-habituation test (HaXha) is a spontaneous odor discrimination task that has been used for many decades to evaluate olfactory function in animals. Animals are presented repeatedly with the same odorant after which a new odorant is introduced. The time the animal explores the odor object is measured. An animal is considered to cross-habituate during the novel stimulus trial when the exploration time is higher than the prior trial and indicates the degree of olfactory patency. On the other hand, habituation across the repeated trials involves decreased exploration time and is related to memory patency, especially at long intervals. Classically exploration is timed using a stopwatch when the animal is within 2 cm of the object and aimed toward it. These criteria are intuitive, but it is unclear how they relate to olfactory exploration, that is, sniffing. We used video tracking combined with plethysmography to improve accuracy, avoid observer bias, and propose more robust criteria for exploratory scoring when sniff measures are not available. We also demonstrate that sniff rate combined with proximity is the most direct measure of odorant exploration and provide a robust and sensitive criterion. PMID:27516910

  5. Individual differences in the habitual use of cognitive reappraisal predict the reward-related processing

    PubMed Central

    Sai, Liyang; Wang, Sisi; Ward, Anne; Ku, Yixuan; Sang, Biao

    2015-01-01

    Recent studies have shown that instructed cognitive reappraisal can regulate the neural processing of reward. However, it is still unclear whether the habitual use of cognitive reappraisal in everyday life is related to brain activity involved in reward processing. In the present study, participants’ neural responses to reward were measured using electroencephalography (EEG) recorded during a gambling task and their tendency to use cognitive reappraisal was assessed using the Emotion Regulation Questionnaire (ERQ). Event-related potential (ERP) results indicated that losses on the gambling task elicited greater negative reward-related feedback negativity (FN) than gains. The differential FN between losses and gains was significantly correlated with cognitive reappraisal scores across participants such that individuals with a higher tendency to use cognitive reappraisal showed stronger reward processing (i.e., amplified FN difference between losses and gains). This correlation remained significant after controlling for expressive suppression scores. However, expressive suppression per se was not correlated with FN differences. Taken together, these results suggest that the habitual use of cognitive reappraisal is associated with increased neural processing of reward. PMID:26388796

  6. Goal-directed, habitual and Pavlovian prosocial behavior

    PubMed Central

    Gęsiarz, Filip; Crockett, Molly J.

    2015-01-01

    Although prosocial behaviors have been widely studied across disciplines, the mechanisms underlying them are not fully understood. Evidence from psychology, biology and economics suggests that prosocial behaviors can be driven by a variety of seemingly opposing factors: altruism or egoism, intuition or deliberation, inborn instincts or learned dispositions, and utility derived from actions or their outcomes. Here we propose a framework inspired by research on reinforcement learning and decision making that links these processes and explains characteristics of prosocial behaviors in different contexts. More specifically, we suggest that prosocial behaviors inherit features of up to three decision-making systems employed to choose between self- and other- regarding acts: a goal-directed system that selects actions based on their predicted consequences, a habitual system that selects actions based on their reinforcement history, and a Pavlovian system that emits reflexive responses based on evolutionarily prescribed priors. This framework, initially described in the field of cognitive neuroscience and machine learning, provides insight into the potential neural circuits and computations shaping prosocial behaviors. Furthermore, it identifies specific conditions in which each of these three systems should dominate and promote other- or self- regarding behavior. PMID:26074797

  7. Psychophysiological effects of habitual caffeine consumption.

    PubMed

    James, J E

    1994-01-01

    Caffeine is the most widely consumed pharmacologically active substance in the world, and a key issue concerning its possible implications for human health is whether it has persistent (i.e., chronic) physiological effects on habitual consumers. This study examined blood pressure, heart rate (HR), electromyogram (EMG), and skin conductance level (SCL) in 36 healthy men and women exposed to a pattern of moderate intake. A double-blind placebo-controlled crossover design with counterbalancing was used in which all subjects participated in four experimental conditions involving the ingestion of placebo or caffeine three times daily for 6 days followed by a seventh ("challenge") day of placebo or caffeine ingestion. Results confirmed that caffeine has significant pressor effects, and these were found to he additive to the pressor action of a laboratory stressor. Following habitual consumption of the drug. pressor effects were diminished (indicative of tolerance) but not eliminated. Effects of caffeine on other parameters were either modest (HR and EMG) or negligible (SCL). Considering (he near-universal use of caffeine. the persistent pressor effects observed in this study have important implications for clinical practice and public health. PMID:16250800

  8. Reduced habituation of auditory evoked potentials indicate cortical hyper-excitability in Fragile X Syndrome.

    PubMed

    Ethridge, L E; White, S P; Mosconi, M W; Wang, J; Byerly, M J; Sweeney, J A

    2016-04-19

    Sensory hypersensitivities are common, clinically distressing features of Fragile X Syndrome (FXS). Preclinical evidence suggests this abnormality may result from synaptic hyper-excitability in sensory systems. This model predicts reduced sensory habituation to repeated stimulus presentation. Fourteen adolescents and adults with FXS and 15 age-matched controls participated in a modified auditory gating task using trains of 4 identical tones during dense array electroencephalography (EEG). Event-related potential and single trial time-frequency analyses revealed decreased habituation of the N1 event-related potential response in FXS, and increased gamma power coupled with decreases in gamma phase-locking during the early-stimulus registration period. EEG abnormalities in FXS were associated with parent reports of heightened sensory sensitivities and social communication deficits. Reduced habituation and altered gamma power and phase-locking to auditory cues demonstrated here in FXS patients parallels preclinical findings with Fmr1 KO mice. Thus, the EEG abnormalities seen in FXS patients support the model of neocortical hyper-excitability in FXS, and may provide useful translational biomarkers for evaluating novel treatment strategies targeting its neural substrate.

  9. Long-term habituation of the C-start escape response in zebrafish larvae.

    PubMed

    Roberts, Adam C; Pearce, Kaycey C; Choe, Ronny C; Alzagatiti, Joseph B; Yeung, Anthony K; Bill, Brent R; Glanzman, David L

    2016-10-01

    The cellular and molecular basis of long-term memory in vertebrates remains poorly understood. Knowledge regarding long-term memory has been impeded by the enormous complexity of the vertebrate brain, particularly the mammalian brain, as well as by the relative complexity of the behavioral alterations examined in most studies of long-term memory in vertebrates. Here, we demonstrate a long-term form of nonassociative learning-specifically, long-term habituation (LTH)-of a simple reflexive escape response, the C-start, in zebrafish larvae. The C-start is triggered by the activation of one of a pair of giant neurons in the zebrafish's hindbrain, the Mauthner cells. We show that LTH of the C-start requires the activity of NMDA receptors and involves macromolecular synthesis. We further show that the long-term habituated reflex can by rapidly dishabituated by a brief tactile stimulus. Our results set the stage for rigorous, mechanistic investigations of the long-term memory for habituation of a reflexive behavioral response, one that is mediated by a relatively simple, neurobiologically tractable, neural circuit. Moreover, the demonstration of NMDAR and transcriptionally dependent LTH in a translucent vertebrate organism should facilitate the use of optical recording, and optogenetic manipulation, of neuronal activity to elucidate the cellular basis of a long-term vertebrate memory. PMID:27555232

  10. Saliency mapping in the optic tectum and its relationship to habituation.

    PubMed

    Dutta, Arkadeb; Gutfreund, Yoram

    2014-01-01

    Habituation of the orienting response has long served as a model system for studying fundamental psychological phenomena such as learning, attention, decisions, and surprise. In this article, we review an emerging hypothesis that the evolutionary role of the superior colliculus (SC) in mammals or its homolog in birds, the optic tectum (OT), is to select the most salient target and send this information to the appropriate brain regions to control the body and brain orienting responses. Recent studies have begun to reveal mechanisms of how saliency is computed in the OT/SC, demonstrating a striking similarity between mammals and birds. The saliency of a target can be determined by how different it is from the surrounding objects, by how different it is from its history (that is habituation) and by how relevant it is for the task at hand. Here, we will first review evidence, mostly from primates and barn owls, that all three types of saliency computations are linked in the OT/SC. We will then focus more on neural adaptation in the OT and its possible link to temporal saliency and habituation. PMID:24474908

  11. Long-term habituation of the C-start escape response in zebrafish larvae.

    PubMed

    Roberts, Adam C; Pearce, Kaycey C; Choe, Ronny C; Alzagatiti, Joseph B; Yeung, Anthony K; Bill, Brent R; Glanzman, David L

    2016-10-01

    The cellular and molecular basis of long-term memory in vertebrates remains poorly understood. Knowledge regarding long-term memory has been impeded by the enormous complexity of the vertebrate brain, particularly the mammalian brain, as well as by the relative complexity of the behavioral alterations examined in most studies of long-term memory in vertebrates. Here, we demonstrate a long-term form of nonassociative learning-specifically, long-term habituation (LTH)-of a simple reflexive escape response, the C-start, in zebrafish larvae. The C-start is triggered by the activation of one of a pair of giant neurons in the zebrafish's hindbrain, the Mauthner cells. We show that LTH of the C-start requires the activity of NMDA receptors and involves macromolecular synthesis. We further show that the long-term habituated reflex can by rapidly dishabituated by a brief tactile stimulus. Our results set the stage for rigorous, mechanistic investigations of the long-term memory for habituation of a reflexive behavioral response, one that is mediated by a relatively simple, neurobiologically tractable, neural circuit. Moreover, the demonstration of NMDAR and transcriptionally dependent LTH in a translucent vertebrate organism should facilitate the use of optical recording, and optogenetic manipulation, of neuronal activity to elucidate the cellular basis of a long-term vertebrate memory.

  12. Saliency mapping in the optic tectum and its relationship to habituation

    PubMed Central

    Dutta, Arkadeb; Gutfreund, Yoram

    2014-01-01

    Habituation of the orienting response has long served as a model system for studying fundamental psychological phenomena such as learning, attention, decisions, and surprise. In this article, we review an emerging hypothesis that the evolutionary role of the superior colliculus (SC) in mammals or its homolog in birds, the optic tectum (OT), is to select the most salient target and send this information to the appropriate brain regions to control the body and brain orienting responses. Recent studies have begun to reveal mechanisms of how saliency is computed in the OT/SC, demonstrating a striking similarity between mammals and birds. The saliency of a target can be determined by how different it is from the surrounding objects, by how different it is from its history (that is habituation) and by how relevant it is for the task at hand. Here, we will first review evidence, mostly from primates and barn owls, that all three types of saliency computations are linked in the OT/SC. We will then focus more on neural adaptation in the OT and its possible link to temporal saliency and habituation. PMID:24474908

  13. Reduced habituation of auditory evoked potentials indicate cortical hyper-excitability in Fragile X Syndrome

    PubMed Central

    Ethridge, L E; White, S P; Mosconi, M W; Wang, J; Byerly, M J; Sweeney, J A

    2016-01-01

    Sensory hypersensitivities are common, clinically distressing features of Fragile X Syndrome (FXS). Preclinical evidence suggests this abnormality may result from synaptic hyper-excitability in sensory systems. This model predicts reduced sensory habituation to repeated stimulus presentation. Fourteen adolescents and adults with FXS and 15 age-matched controls participated in a modified auditory gating task using trains of 4 identical tones during dense array electroencephalography (EEG). Event-related potential and single trial time–frequency analyses revealed decreased habituation of the N1 event-related potential response in FXS, and increased gamma power coupled with decreases in gamma phase-locking during the early-stimulus registration period. EEG abnormalities in FXS were associated with parent reports of heightened sensory sensitivities and social communication deficits. Reduced habituation and altered gamma power and phase-locking to auditory cues demonstrated here in FXS patients parallels preclinical findings with Fmr1 KO mice. Thus, the EEG abnormalities seen in FXS patients support the model of neocortical hyper-excitability in FXS, and may provide useful translational biomarkers for evaluating novel treatment strategies targeting its neural substrate. PMID:27093069

  14. Psychological and neural mechanisms of experimental extinction: a selective review.

    PubMed

    Delamater, Andrew R; Westbrook, R Frederick

    2014-02-01

    The present review examines key psychological concepts in the study of experimental extinction and implications these have for an understanding of the underlying neurobiology of extinction learning. We suggest that many of the signature characteristics of extinction learning (spontaneous recovery, renewal, reinstatement, rapid reacquisition) can be accommodated by the standard associative learning theory assumption that extinction results in partial erasure of the original learning together with new inhibitory learning. Moreover, we consider recent behavioral and neural evidence that supports the partial erasure view of extinction, but also note shortcomings in our understanding of extinction circuits as these relate to the negative prediction error concept. Recent work suggests that common prediction error and stimulus-specific prediction error terms both may be required to explain neural plasticity both in acquisition and extinction learning. In addition, we suggest that many issues in the content of extinction learning have not been fully addressed in current research, but that neurobiological approaches should be especially helpful in addressing such issues. These include questions about the nature of extinction learning (excitatory CS-No US, inhibitory CS-US learning, occasion setting processes), especially as this relates to studies of the micro-circuitry of extinction, as well as its representational content (sensory, motivational, response). An additional understudied problem in extinction research is the role played by attention processes and their underlying neural networks, although some research and theory converge on the idea that extinction is accompanied by attention decrements (i.e., habituation-like processes). PMID:24104049

  15. Psychological and neural mechanisms of experimental extinction: a selective review.

    PubMed

    Delamater, Andrew R; Westbrook, R Frederick

    2014-02-01

    The present review examines key psychological concepts in the study of experimental extinction and implications these have for an understanding of the underlying neurobiology of extinction learning. We suggest that many of the signature characteristics of extinction learning (spontaneous recovery, renewal, reinstatement, rapid reacquisition) can be accommodated by the standard associative learning theory assumption that extinction results in partial erasure of the original learning together with new inhibitory learning. Moreover, we consider recent behavioral and neural evidence that supports the partial erasure view of extinction, but also note shortcomings in our understanding of extinction circuits as these relate to the negative prediction error concept. Recent work suggests that common prediction error and stimulus-specific prediction error terms both may be required to explain neural plasticity both in acquisition and extinction learning. In addition, we suggest that many issues in the content of extinction learning have not been fully addressed in current research, but that neurobiological approaches should be especially helpful in addressing such issues. These include questions about the nature of extinction learning (excitatory CS-No US, inhibitory CS-US learning, occasion setting processes), especially as this relates to studies of the micro-circuitry of extinction, as well as its representational content (sensory, motivational, response). An additional understudied problem in extinction research is the role played by attention processes and their underlying neural networks, although some research and theory converge on the idea that extinction is accompanied by attention decrements (i.e., habituation-like processes).

  16. Synaptic depression and short-term habituation are located in the sensory part of the mammalian startle pathway

    PubMed Central

    Simons-Weidenmaier, Nadine S; Weber, Maruschka; Plappert, Claudia F; Pilz, Peter KD; Schmid, Susanne

    2006-01-01

    Background Short-term habituation of the startle response represents an elementary form of learning in mammals. The underlying mechanism is located within the primary startle pathway, presumably at sensory synapses on giant neurons in the caudal pontine reticular nucleus (PnC). Short trains of action potentials in sensory afferent fibers induce depression of synaptic responses in PnC giant neurons, a phenomenon that has been proposed to be the cellular correlate for short-term habituation. We address here the question whether both this synaptic depression and the short-term habituation of the startle response are localized at the presynaptic terminals of sensory afferents. If this is confirmed, it would imply that these processes take place prior to multimodal signal integration, rather than occurring at postsynaptic sites on PnC giant neurons that directly drive motor neurons. Results Patch-clamp recordings in vitro were combined with behavioral experiments; synaptic depression was specific for the input pathway stimulated and did not affect signals elicited by other sensory afferents. Concordant with this, short-term habituation of the acoustic startle response in behavioral experiments did not influence tactile startle response amplitudes and vice versa. Further electrophysiological analysis showed that the passive properties of the postsynaptic neuron were unchanged but revealed some alterations in short-term plasticity during depression. Moreover, depression was induced only by trains of presynaptic action potentials and not by single pulses. There was no evidence for transmitter receptor desensitization. In summary, the data indicates that the synaptic depression mechanism is located presynaptically. Conclusion Our electrophysiological and behavioral data strongly indicate that synaptic depression in the PnC as well as short-term habituation are located in the sensory part of the startle pathway, namely at the axon terminals of sensory afferents in the Pn

  17. Infant Temperament and Subject Loss in a Habituation Procedure.

    ERIC Educational Resources Information Center

    Wachs, Theodore D.; Smitherman, Colleen H.

    1985-01-01

    A total of 114 infants at three age levels (11, 18, and 28 weeks) were rated by their mothers on a termperament questionnaire and subjected to a habituation procedure. Results suggest that subject loss in habituation studies may be the result of nonrandom individual difference factors and not just the result of temporary fluctuations in state.…

  18. Protection from Premature Habituation Requires Functional Mushroom Bodies in "Drosophila"

    ERIC Educational Resources Information Center

    Acevedo, Summer F.; Froudarakis, Emmanuil I.; Kanellopoulos, Alexandros; Skoulakis, Efthimios M. C.

    2007-01-01

    Diminished responses to stimuli defined as habituation can serve as a gating mechanism for repetitive environmental cues with little predictive value and importance. We demonstrate that wild-type animals diminish their responses to electric shock stimuli with properties characteristic of short- and long-term habituation. We used spatially…

  19. Gender differences in habitual activity in children with cystic fibrosis

    PubMed Central

    Selvadurai, H; Blimkie, C; Cooper, P; Mellis, C; Van Asperen, P P

    2004-01-01

    Aims: (1) To compare habitual activity levels in prepubescent and pubescent boys and girls with different degrees of CF lung disease severity and healthy controls. (2) To assess the relation between habitual activity levels and measures of fitness, lung function, nutrition, pancreatic status, and quality of life. Methods and Results: A total of 148 children (75 girls and 73 boys) with CF and matched controls were studied. Regardless of disease severity, there were no differences in habitual activity between prepubescent boys and girls with CF. Pubescent boys with CF were significantly more active than girls with the same degree of disease severity. There were no significant differences in habitual activity between prepubescent children with CF and controls. Pubescent children with mild CF were significantly more active than controls, but those with moderate to severe disease were less active than controls. The best correlates with habitual activity levels were anaerobic power, aerobic capacity, and quality of life. In children with moderate to severe disease, nutrition status correlated significantly with activity levels. The impact of pancreatic status on activity levels and other measures of fitness was most apparent in pubescent girls. Conclusion: Gender differences in habitual activity were evident only after the onset of puberty. The impact of pancreatic insufficiency on measures of fitness and habitual activity was greatest in pubescent females. The reason for this gender difference may be an interplay of genetic, hormonal, and societal factors and is the focus of a longitudinal study. PMID:15383436

  20. Habituation of LG-mediated tailflip in the crayfish.

    PubMed

    Nagayama, Toshiki; Araki, Makoto

    2015-06-01

    Crayfish escape from threatening stimuli by tailflipping. If a stimulus is applied to the rear, crayfish escape up and forwards in a summersault maneuver that is mediated by the activation of lateral giant (LG) interneurons. The occurrence probability of LG-mediated tailflip, however, diminishes and habituates if a stimulus is repeatedly applied. Since crayfish have a relatively simple CNS with many identifiable neurons, crayfish represent a good animal to analyze the cellular basis of habituation. A reduction in the amplitude of the EPSP in the LGs, caused by direct chemical synaptic connection from sensory afferents by repetitive stimulations, is essential to bring about an inactivation of the LGs. The spike response of the LGs recovers within several minutes of habituation, but the LGs subsequently fail to spike when an additional stimulus is applied after specific periods following habituation. These results indicate that a decline in synaptic efficacy from the mechanosensory afferents recovers readily after a short delay, but then the excitability of the LGs themselves decreases. Furthermore, the processes underlying habituation are modulated depending on a social status. When two crayfish encounter each other, a winner-loser relationship is established. With a short interstimulus interval of 5 s, the rate of habituation of the LG in both socially dominant and subordinate crayfish becomes lower than in socially isolated animals. Serotonin and octopamine affect this social status-dependent modulation of habituation by means of activation of downstream second messenger system of cAMP and IP3 cascades, respectively.

  1. Rapid habituation by mosquito larvae to predator kairomones.

    PubMed

    Roberts, Derek

    2014-12-01

    Larvae of some species of mosquitoes have been shown to respond to water-borne kairomones from predators by reducing bottom-feeding and replacing it with surface filter-feeding, which uses less movement and is thus less likely to attract a predator. However, if no predator attack takes place, then it would be more efficient to use a risk allocation strategy of habituating their response depending on the predator and the overall risk. The larvae of Culiseta longiareolata Macquart live in temporary rain-filled pools, where they are exposed to a high level of predation. Within one hour, they responded to kairomones from dragonfly or damselfly nymphs, or to the fish Aphanius, by significantly reducing bottom-feeding activity. Continued exposure to the predator kairomones resulted in habituation of their response to damselflies, a slower habituation to fish, but no habituation to dragonflies even after 30 h. In contrast, the larvae of Culex quinquefasciatus Say normally live in highly polluted and thus anaerobic water, where the predation risk will be much lower. They also showed a significant reduction in bottom-feeding after 1 h of exposure to predator kairomones but had completely habituated this response within 6 h of continuous exposure. Some species of mosquito larvae can thus show a very rapid habituation to predator kairomones, while others only habituate slowly depending on the predator and overall predation risk. PMID:25424265

  2. Plastic Surgery

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A ... her forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word " ...

  3. An unexpected increase in restraint duration alters the expression of stress response habituation

    PubMed Central

    Kearns, Rachael R.; Spencer, Robert L.

    2013-01-01

    While habituation develops to a repeated psychological stressor, manipulating certain parameters of the stress challenge experience may lead to dishabituation of the stress response. In this experiment, we investigated whether the behavioral, endocrine, and neural responses (c-fos mRNA immediate early gene expression) to a psychological stressor (restraint) differ when the duration of the stressor given on the test day violates expectations based on prior stress experience. Rats experienced 10 min of daily restraint on Days 1-4 followed by challenge with either the same duration (10 min) or a longer duration (30 min) of restraint on Day 5. Rats’ behavior was video recorded during the Day 5 restraint episode, and trunk blood and brain tissue were collected 30 min following restraint onset. Struggling behavior was manually scored as active attempts to escape the restraint device. Rats who experienced the same duration of repeated restraint showed a significant decrease of plasma corticosterone (CORT) compared to the 10 min acute restraint group (habituation). In addition, these rats showed decreased active struggling over repeated restraint trials. Conversely, the rats showed an increased CORT response (dishabituation) when they experienced a longer duration of restraint on Day 5 than they had previously. These rats showed a habituated behavioral response during the first 10 min of restraint, however struggling behavior increased once the duration of restraint exceeded the expected duration (with a peak at 12 min). This peak in struggling behavior did not occur during 30 min acute restraint, indicating that the effect was related to memory of previous restraint experience and not due to a longer duration of restraint. In contrast, these animals showed habituated c-fos mRNA expression in the paraventricular nucleus (PVN), lateral septum (LS), and medial prefrontal cortex (mPFC) in response to the increased stressor duration. Thus, there was dissociation between c

  4. Relationship between food habituation and reinforcing efficacy of food

    PubMed Central

    Carr, Katelyn A.; Epstein, Leonard H.

    2011-01-01

    Reinforcing value and habituation are two processes that have been used to study eating behaviors, but no research has examined their relationship, how they relate to energy intake, and whether they respond in a similar manner to food deprivation. Twenty-two female subjects were randomized to food deprived or non-deprived conditions, and assessed for food reinforcement, habituation to food and ad libitum eating. Results showed food reinforcement and habituation are correlated (r = 0.62, p = 0.002) and both independently predict energy intake. Hierarchical regression showed that the rate of habituation accounted for 30 percent of the variance in eating (p = 0.008), and adding food reinforcement increased the amount of variance accounted for up to 57.5 percent (p < 0.05). This suggests that both processes may influence energy intake in a meal. PMID:21423567

  5. Disruption of exploratory and habituation behavior in mice with mutation of DISC1: an ethologically based analysis.

    PubMed

    Walsh, J; Desbonnet, L; Clarke, N; Waddington, J L; O'Tuathaigh, C M P

    2012-07-01

    Disrupted-in-schizophrenia-1 (DISC1) is a gene that has been functionally linked with neurodevelopmental processes and structural plasticity in the brain. Clinical genetic investigations have implicated DISC1 as a genetic risk factor for schizophrenia and related psychoses. Studies using mutant mouse models of DISC1 gene function have demonstrated schizophrenia-related anatomical and behavioral endophenotypes. In the present study, ethologically based assessment of exploratory and habituation behavior in the open field was conducted in DISC1 (L100P), wild-type (WT), heterozygous (HET), and homozygous (HOM) mutant mice of both sexes. Ethological assessment was conducted in an open-field environment to explore specific topographies of murine exploratory behavior across the extended course of interaction from initial exploration through subsequent habituation (the ethogram). During initial exploration, HET and HOM DISC1 mutants evidenced increased levels of locomotion and rearing to wall compared with WT. A HOM-specific increase in total rearing and a HET-specific increase in sifting behavior and reduction in rearing seated were also observed. Over subsequent habituation, locomotion, sniffing, total rearing, rearing to wall, rearing free, and rearing seated were increased in HET and HOM mutants vs. WT. Overall, grooming was increased in HOM relative to other genotypes. HET mice displayed a selective decrease in habituation of sifting behavior. These data demonstrate impairment in both initial exploratory and habituation of exploration in a novel environment in mice with mutation of DISC1. This is discussed in the context of the functional role of the gene vis à vis a schizophrenia phenotype as well as the value of ethologically based approaches to behavioral phenotyping.

  6. Nocebo context modulates long-term habituation to heat pain and influences functional connectivity of the operculum.

    PubMed

    Ellerbrock, Isabel; Wiehler, Antonius; Arndt, Manuela; May, Arne

    2015-11-01

    In the past, nocebo manipulations have been found to modulate pain perception and influence long-term habituation to pain. Recently, neural correlates accompanying this finding have been identified: habituation over days is mirrored by decreased activity in pain-processing brain areas, whereas nocebo-specific modulation specifically involves the opercular cortex. Focusing on duration and central network characteristics of nocebo information in a longitudinal heat pain paradigm, we investigated 40 healthy participants over a period of 21 consecutive days, whereof sessions on days 1, 8, 14, and 21 were performed during functional magnetic resonance imaging scanning. Negative context information was given to half of the participants, inducing a nocebo manipulation through verbal suggestions. The analysis was focused on brain areas associated with habituation and nocebo effects and identified coupled brain regions using functional connectivity analysis. Decreased pain perception over days was reflected in reduced blood oxygenation level dependent signal in pain-processing areas, such as the insula and somatosensory cortices, whereas increased rostral anterior cingulate cortex activation reflected the central correlate for habituation over time. Habituation was significantly less pronounced in the nocebo group. Consistent with previous results, the nocebo manipulation not only modulated pain perception but also was accompanied by the activation of the operculum over an extended period of time. Importantly, the operculum exhibited changes in coupling during nociceptive input over time, as demonstrated by decreased connectivity with the basal ganglia and pinpoints differences, depending on whether a nocebo context was given. These data suggest that negative verbal suggestions prognosticating increasing pain may prevail by modulating basal ganglia-thalamocortical loops. PMID:26181304

  7. Nocebo context modulates long-term habituation to heat pain and influences functional connectivity of the operculum.

    PubMed

    Ellerbrock, Isabel; Wiehler, Antonius; Arndt, Manuela; May, Arne

    2015-11-01

    In the past, nocebo manipulations have been found to modulate pain perception and influence long-term habituation to pain. Recently, neural correlates accompanying this finding have been identified: habituation over days is mirrored by decreased activity in pain-processing brain areas, whereas nocebo-specific modulation specifically involves the opercular cortex. Focusing on duration and central network characteristics of nocebo information in a longitudinal heat pain paradigm, we investigated 40 healthy participants over a period of 21 consecutive days, whereof sessions on days 1, 8, 14, and 21 were performed during functional magnetic resonance imaging scanning. Negative context information was given to half of the participants, inducing a nocebo manipulation through verbal suggestions. The analysis was focused on brain areas associated with habituation and nocebo effects and identified coupled brain regions using functional connectivity analysis. Decreased pain perception over days was reflected in reduced blood oxygenation level dependent signal in pain-processing areas, such as the insula and somatosensory cortices, whereas increased rostral anterior cingulate cortex activation reflected the central correlate for habituation over time. Habituation was significantly less pronounced in the nocebo group. Consistent with previous results, the nocebo manipulation not only modulated pain perception but also was accompanied by the activation of the operculum over an extended period of time. Importantly, the operculum exhibited changes in coupling during nociceptive input over time, as demonstrated by decreased connectivity with the basal ganglia and pinpoints differences, depending on whether a nocebo context was given. These data suggest that negative verbal suggestions prognosticating increasing pain may prevail by modulating basal ganglia-thalamocortical loops.

  8. Computing with neural synchrony.

    PubMed

    Brette, Romain

    2012-01-01

    Neurons communicate primarily with spikes, but most theories of neural computation are based on firing rates. Yet, many experimental observations suggest that the temporal coordination of spikes plays a role in sensory processing. Among potential spike-based codes, synchrony appears as a good candidate because neural firing and plasticity are sensitive to fine input correlations. However, it is unclear what role synchrony may play in neural computation, and what functional advantage it may provide. With a theoretical approach, I show that the computational interest of neural synchrony appears when neurons have heterogeneous properties. In this context, the relationship between stimuli and neural synchrony is captured by the concept of synchrony receptive field, the set of stimuli which induce synchronous responses in a group of neurons. In a heterogeneous neural population, it appears that synchrony patterns represent structure or sensory invariants in stimuli, which can then be detected by postsynaptic neurons. The required neural circuitry can spontaneously emerge with spike-timing-dependent plasticity. Using examples in different sensory modalities, I show that this allows simple neural circuits to extract relevant information from realistic sensory stimuli, for example to identify a fluctuating odor in the presence of distractors. This theory of synchrony-based computation shows that relative spike timing may indeed have computational relevance, and suggests new types of neural network models for sensory processing with appealing computational properties.

  9. Computing with Neural Synchrony

    PubMed Central

    Brette, Romain

    2012-01-01

    Neurons communicate primarily with spikes, but most theories of neural computation are based on firing rates. Yet, many experimental observations suggest that the temporal coordination of spikes plays a role in sensory processing. Among potential spike-based codes, synchrony appears as a good candidate because neural firing and plasticity are sensitive to fine input correlations. However, it is unclear what role synchrony may play in neural computation, and what functional advantage it may provide. With a theoretical approach, I show that the computational interest of neural synchrony appears when neurons have heterogeneous properties. In this context, the relationship between stimuli and neural synchrony is captured by the concept of synchrony receptive field, the set of stimuli which induce synchronous responses in a group of neurons. In a heterogeneous neural population, it appears that synchrony patterns represent structure or sensory invariants in stimuli, which can then be detected by postsynaptic neurons. The required neural circuitry can spontaneously emerge with spike-timing-dependent plasticity. Using examples in different sensory modalities, I show that this allows simple neural circuits to extract relevant information from realistic sensory stimuli, for example to identify a fluctuating odor in the presence of distractors. This theory of synchrony-based computation shows that relative spike timing may indeed have computational relevance, and suggests new types of neural network models for sensory processing with appealing computational properties. PMID:22719243

  10. One night of partial sleep deprivation affects habituation of hypothalamus and skin conductance responses.

    PubMed

    Peters, Anja C; Blechert, Jens; Sämann, Philipp G; Eidner, Ines; Czisch, Michael; Spoormaker, Victor I

    2014-09-15

    Sleep disturbances are prevalent in clinical anxiety, but it remains unclear whether they are cause and/or consequence of this condition. Fear conditioning constitutes a valid laboratory model for the acquisition of normal and pathological anxiety. To explore the relationship between disturbed sleep and anxiety in more detail, the present study evaluated the effect of partial sleep deprivation (SD) on fear conditioning in healthy individuals. The neural correlates of 1) nonassociative learning and physiological processing and 2) associative learning (differential fear conditioning) were addressed. Measurements entailed simultaneous functional MRI, EEG, skin conductance response (SCR), and pulse recordings. Regarding nonassociative learning, partial SD resulted in a generalized failure to habituate during fear conditioning, as evidenced by reduced habituation of SCR and hypothalamus responses to all stimuli. Furthermore, SCR and hypothalamus activity were correlated, supporting their functional relationship. Regarding associative learning, effects of partial SD on the acquisition of conditioned fear were weaker and did not reach statistical significance. The hypothalamus plays an integral role in the regulation of sleep and autonomic arousal. Thus sleep disturbances may play a causal role in the development of normal and possibly pathological fear by increasing the susceptibility of the sympathetic nervous system to stressful experiences.

  11. Dynamic role of postsynaptic caspase-3 and BIRC4 in zebra finch song response habituation

    PubMed Central

    Huesmann, Graham R.; Clayton, David F.

    2007-01-01

    Summary Activation of the protease caspase-3 is commonly thought to cause apoptotic cell death. Here we show that caspase-3 activity is regulated at postsynaptic sites in brain following stimuli associated with memory (neural activation and subsequent response habituation) instead of cell death. In the zebra finch auditory forebrain, the concentration of caspase-3 active sites increases briefly within minutes after exposure to tape-recorded birdsong. With confocal and immunoelectron microscopy, we localize the activated enzyme to dendritic spines. The activated caspase-3 protein is present even in unstimulated brain but bound to an endogenous inhibitor, BIRC4 (xIAP), suggesting a mechanism for rapid release and sequestering at specific synaptic sites. Caspase-3 activity is necessary to consolidate a persistent physiological trace of the song stimulus, as demonstrated using pharmacological interference and the zenk gene habituation assay. Thus the brain appears to have adapted a core component of cell death machinery to serve a unique role in learning and memory. PMID:17178408

  12. [Plasticity of the cellular phenotype].

    PubMed

    Chneiweiss, Hervé

    2011-01-01

    The tragical consequences of the Hiroshima and Nagasaki atomic bombs in 1945 were to lead to the discovery of hematopoietic stem cells and their phenotypic plasticity, in response to environmental factors. These concepts were much later extended to the founding cells of other tissues. In the following collection of articles, the mechanisms underlying this plasticity, at the frontiers of developmental biology and oncology, are illustrated in the case of various cell types of neural origin and of some tumours. PMID:21501574

  13. [Plasticity of the cellular phenotype].

    PubMed

    Chneiweiss, Hervé

    2011-01-01

    The tragical consequences of the Hiroshima and Nagasaki atomic bombs in 1945 were to lead to the discovery of hematopoietic stem cells and their phenotypic plasticity, in response to environmental factors. These concepts were much later extended to the founding cells of other tissues. In the following collection of articles, the mechanisms underlying this plasticity, at the frontiers of developmental biology and oncology, are illustrated in the case of various cell types of neural origin and of some tumours.

  14. Stimulus-specific adaptation, habituation and change detection in the gaze control system.

    PubMed

    Gutfreund, Yoram

    2012-12-01

    This prospect article addresses the neurobiology of detecting and responding to changes or unexpected events. Change detection is an ongoing computational task performed by the brain as part of the broader process of saliency mapping and selection of the next target for attention. In the optic tectum (OT) of the barn owl, the probability of the stimulus has a dramatic influence on the neural response to that stimulus; rare or deviant stimuli induce stronger responses compared to common stimuli. This phenomenon, known as stimulus-specific adaptation, has recently attracted scientific interest because of its possible role in change detection. In the barn owl's OT, it may underlie the ability to orient specifically to unexpected events and is therefore opening new directions for research on the neurobiology of fundamental psychological phenomena such as habituation, attention, and surprise. PMID:22711216

  15. Habituation in the Tail Withdrawal Reflex Circuit is Impaired During Aging in Aplysia californica

    PubMed Central

    Kempsell, Andrew T.; Fieber, Lynne A.

    2016-01-01

    The relevance of putative contributors to age-related memory loss are poorly understood. The tail withdrawal circuit of the sea hare, a straightforward neural model, was used to investigate the aging characteristics of rudimentary learning. The simplicity of this neuronal circuit permits attribution of declines in the function of specific neurons to aging declines. Memory was impaired in advanced age animals compared to their performance at the peak of sexual maturity, with habituation training failing to attenuate the tail withdrawal response or to reduce tail motoneuron excitability, as occurred in peak maturity siblings. Baseline motoneuron excitability of aged animals was significantly lower, perhaps contributing to a smaller scope for attenuation. Conduction velocity in afferent fibers to tail sensory neurons (SN) decreased during aging. The findings suggest that age-related changes in tail sensory and motor neurons result in deterioration of a simple form of learning in Aplysia. PMID:26903863

  16. Plastic Jellyfish.

    ERIC Educational Resources Information Center

    Moseley, Christine

    2000-01-01

    Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)

  17. Common processes may contribute to extinction and habituation.

    PubMed

    McSweeney, Frances K; Swindell, Samantha

    2002-10-01

    Psychologists routinely attribute the characteristics of conditioned behavior to complicated cognitive processes. For example, many of the characteristics of behavior undergoing extinction have been attributed to retrieval from memory. The authors argue that these characteristics may result from the simpler process of habituation. In particular, conditioned responding may decrease during extinction partially because habituation occurs to the stimuli that control responding when those stimuli are presented repeatedly or for a prolonged time (e.g., the experimental context, the conditioned stimulus in classical conditioning). This idea is parsimonious, has face validity, and evokes only processes that are well established by other evidence. In addition, behavior undergoing extinction shows 12 of the fundamental properties of behavior undergoing habituation. However, this model probably cannot provide a complete theory of extinction. It provides no obvious explanation for some of the other characteristics of extinguished behavior.

  18. Development of skin conductance orienting, habituation, and reorienting from ages 3 to 8 years: a longitudinal latent growth curve analysis.

    PubMed

    Gao, Yu; Raine, Adrian; Dawson, Michael E; Venables, Peter H; Mednick, Sarnoff A

    2007-11-01

    Little is known about the development of the skin conductance orienting response (SCOR) in childhood. This longitudinal study examines the effects of age on initial SCOR, habituation, and reorienting. Skin conductance responses to nonsignal auditory stimuli were recorded from 200 male and female children at five different time points (ages 3, 4, 5, 6, and 8 years). Longitudinal latent growth curve analyses were used to determine the trajectory of each SCOR measure during this period. Results indicated that (a) initial SCOR is present at age 3, increases thereafter to peak at age 6, and then levels off, (b) habituation is absent at age 3, but becomes apparent at age 4 years and increases thereafter with increasing age, (c) SC reorienting is absent from ages 3 to 8, and (d) boys and girls do not exhibit different developmental trajectories. Results suggest that from age 3 to 8 years, the transition from the functionally immature to mature neural network underlying orienting and habituation is a continuous process and may be related to children's cognitive development during this period.

  19. Influence of mobility restriction on habituation of the vestibular apparatus

    NASA Technical Reports Server (NTRS)

    Gorgiladze, G. I.; Kazanskaya, G. S.

    1980-01-01

    Test results presented indicate that 30-day hypokinesia did not affect the intensity of nystagmus: velocity of slow phase, total number of jerks, and duration of the reaction in animals were the same as before mobility restriction and did not differ from those of the control group. However, hypokinesia resulted in the disappearance of habituation of the vestibulary system to repeated angular accelerations. The known hypokinetic changes in the endocrine system were studied. It was concluded that reduction in adrenergic function may be the cause of disappearance of vestibular apparatus habituation during hypokinesia.

  20. Cortical and thalamic connectivity of the auditory anterior ectosylvian cortex of early-deaf cats: Implications for neural mechanisms of crossmodal plasticity.

    PubMed

    Meredith, M Alex; Clemo, H Ruth; Corley, Sarah B; Chabot, Nicole; Lomber, Stephen G

    2016-03-01

    Early hearing loss leads to crossmodal plasticity in regions of the cerebrum that are dominated by acoustical processing in hearing subjects. Until recently, little has been known of the connectional basis of this phenomenon. One region whose crossmodal properties are well-established is the auditory field of the anterior ectosylvian sulcus (FAES) in the cat, where neurons are normally responsive to acoustic stimulation and its deactivation leads to the behavioral loss of accurate orienting toward auditory stimuli. However, in early-deaf cats, visual responsiveness predominates in the FAES and its deactivation blocks accurate orienting behavior toward visual stimuli. For such crossmodal reorganization to occur, it has been presumed that novel inputs or increased projections from non-auditory cortical areas must be generated, or that existing non-auditory connections were 'unmasked.' These possibilities were tested using tracer injections into the FAES of adult cats deafened early in life (and hearing controls), followed by light microscopy to localize retrogradely labeled neurons. Surprisingly, the distribution of cortical and thalamic afferents to the FAES was very similar among early-deaf and hearing animals. No new visual projection sources were identified and visual cortical connections to the FAES were comparable in projection proportions. These results support an alternate theory for the connectional basis for cross-modal plasticity that involves enhanced local branching of existing projection terminals that originate in non-auditory as well as auditory cortices. PMID:26724756

  1. Planned, Motivated and Habitual Hygiene Behaviour: An Eleven Country Review

    ERIC Educational Resources Information Center

    Curtis, Valerie A.; Danquah, Lisa O.; Aunger, Robert V.

    2009-01-01

    Handwashing with soap (HWWS) may be one of the most cost-effective means of preventing infection in developing countries. However, HWWS is rare in these settings. We reviewed the results of formative research studies from 11 countries so as to understand the planned, motivated and habitual factors involved in HWWS. On average, only 17% of child…

  2. Measuring Habituation in Infants: An Approach Using Regression Analysis.

    ERIC Educational Resources Information Center

    Ashmead, Daniel H.; Davis, DeFord L.

    1996-01-01

    Used computer simulations to examine effectiveness of different criteria for measuring infant visual habituation. Found that a criterion based on fitting a second-order polynomial regression function to looking-time data produced more accurate estimation of looking times and higher power for detecting novelty effects than did the traditional…

  3. Use of Terrestrial Hermit Crabs in the Study of Habituation

    ERIC Educational Resources Information Center

    Nolan, Laurence J.

    2004-01-01

    For small colleges, the use of invertebrates in undergraduate learning laboratory experiments may be a valuable alternative to the use of vertebrate species. This article describes a habituation experiment using terrestrial hermit crabs. All of the materials required are inexpensive and readily available. What makes this experiment unique is that…

  4. Moral Education, Habituation, and Divine Assistance in View of Ghazali

    ERIC Educational Resources Information Center

    Attaran, Mohammad

    2015-01-01

    This article describes the concept of moral education and its foundation according to Abu Hamid Ghazali as one of the most influential scholars in the world of Islam. Ghazali equates moral education with habituation. Causality holds a prominent place in philosophical foundations of his theory of moral education. Even though Ghazali recommends…

  5. Relationship between Food Habituation and Reinforcing Efficacy of Food

    ERIC Educational Resources Information Center

    Carr, Katelyn A.; Epstein, Leonard H.

    2011-01-01

    Reinforcing value and habituation are two processes that have been used to study eating behaviors, but no research has examined their relationship, how they relate to energy intake, and whether they respond in a similar manner to food deprivation. Twenty-two female subjects were randomized to food deprived or non-deprived conditions, and assessed…

  6. The problem of consciousness in habitual decision making.

    PubMed

    Bernacer, Javier; Balderas, Gloria; Martinez-Valbuena, Ivan; Pastor, Maria A; Murillo, Jose Ignacio

    2014-02-01

    Newell & Shanks (N&S) carry out an extremely sharp and static distinction between conscious and unconscious decisions, ignoring a process that dynamically transfers decisions and actions between the conscious and unconscious domains of the mind: habitual decision making. We propose a new categorisation and discuss the main characteristics of this process from a philosophical and neuroscientific perspective.

  7. Developmental, sexual and reproductive differences in habituation shown by the guppy (Poecilia reticulata).

    PubMed

    Laming, P R; Loughlin, P B

    1987-01-01

    Behavioural arousal responses of guppies (Poecilia reticulata) were observed to repeated presentation of 2 seconds increased illumination at 30 second intervals. Habituation of responses occurred more rapidly in males than in females and habituation in females was related to their reproductive state. Exposure of gravid females for 8 days to a daily series of stimuli resulted in their young having enhanced habituation postnatally. The results are discussed in relation to developmental and possible hormonal influences on arousal and its habituation in fish.

  8. Effect of interpersonal and cognitive stressors on habituation and the utility of heart rate variability to measure habituation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interpersonal stressors promote eating. Habituation to the sensory properties of a food slows or stops motivated responding for a food. Stress may increase eating by acting as a dishabituator that prolongs responding for a food. Mental arithmetic (memory requirements), Stroop task (cognitive disson...

  9. Using Habituation of Looking Time to Assess Mental Processes in Infancy

    ERIC Educational Resources Information Center

    Oakes, Lisa M.

    2010-01-01

    Habituation of looking time has become the standard method for studying cognitive processes in infancy. This method has a long history and derives from the study of memory and habituation itself. Often, however, it is not clear how researchers make decisions about how to implement habituation as a tool to study processes such as categorization,…

  10. Sensitization and Habituation of Motivated Behavior in Overweight and Non-Overweight Children

    ERIC Educational Resources Information Center

    Epstein, Leonard H.; Robinson, Jodie L.; Temple, Jennifer L.; Roemmich, James N.; Marusewski, Angela; Nadbrzuch, Rachel

    2008-01-01

    The rate of habituation to food is inversely related to energy intake, and overweight children may habituate slower to food and consume more energy. This study compared patterns of sensitization, as defined by an initial increase in operant or motivated responding for food, and habituation, defined by gradual reduction in responding, for macaroni…

  11. Visual Habituation and Dishabituation in Preterm Infants: A Review and Meta-Analysis

    ERIC Educational Resources Information Center

    Kavsek, Michael; Bornstein, Marc H.

    2010-01-01

    We review comparative studies of infant habituation and dishabituation performance focusing on preterm infants. Habituation refers to cognitive encoding, and dishabituation refers to discrimination and memory. If habituation and dishabituation constitute basic information-processing skills, and preterm infants suffer cognitive disadvantages, then…

  12. Transcriptional Analysis of a Whole-Body Form of Long-Term Habituation in "Aplysia Californica"

    ERIC Educational Resources Information Center

    Holmes, Geraldine; Herdegen, Samantha; Schuon, Jonathan; Cyriac, Ashly; Lass, Jamie; Conte, Catherine; Calin-Jageman, Irina E.; Calin-Jageman, Robert J.

    2015-01-01

    Habituation is the simplest form of learning, but we know little about the transcriptional mechanisms that encode long-term habituation memory. A key obstacle is that habituation is relatively stimulus-specific and is thus encoded in small sets of neurons, providing poor signal/noise ratios for transcriptional analysis. To overcome this obstacle,…

  13. Amygdala Habituation and Prefrontal Functional Connectivity in Youth with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Swartz, Johnna R.; Wiggins, Jillian Lee; Carrasco, Melissa; Lord, Catherine; Monk, Christopher S.

    2013-01-01

    Objective: Amygdala habituation, the rapid decrease in amygdala responsiveness to the repeated presentation of stimuli, is fundamental to the nervous system. Habituation is important for maintaining adaptive levels of arousal to predictable social stimuli and decreased habituation is associated with heightened anxiety. Input from the ventromedial…

  14. Foetal response to maternal coffee intake: role of habitual versus non-habitual caffeine consumption.

    PubMed

    Mulder, E J H; Tegaldo, L; Bruschettini, P; Visser, G H A

    2010-11-01

    Little is known about the effect on the human foetus of long-term and acute exposure to caffeine. We studied the organisation of foetal sleep-wake states in 13 healthy near-term foetuses over a wide range of maternal plasma caffeine concentrations (0-13 μg/mL) reflecting normal lifestyle conditions (day 0) and again following intake of two cups of regular coffee (~300 mg of caffeine) intermitted by 50 h of abstinence (day 2; acute effects). On either day, 2 h simultaneous recordings were made of foetal heart rate, general-, eye-, and breathing-movements. The recordings were analysed for the presence of each of four foetal behavioural states: quiet- and active-sleep, quiet- and active-wakefulness. There was a linear relationship between maternal caffeine content and the incidence of foetal general movements during active sleep on day 0 (R = 0.74; P < 0.02). After coffee loading on day 2, foetuses of non- or low-caffeine consumers showed increases in active wakefulness (P < 0.001), general movements (P < 0.05) and heart rate variation (P < 0.01) but lower basal heart rate (P < 0.01) compared with their day 0 values. The changes in foetal heart rate (variation) and behaviour occurred between 90 and 180 min post-consumption. In contrast, foetuses of habitual caffeine consumers remained unaffected suggestive of foetal tolerance to caffeine. The results indicate differential performance between foetuses regularly exposed to caffeine and those caffeine-naive, both under normal maternal lifestyle conditions and in response to maternal coffee ingestion.

  15. Plastics Technology.

    ERIC Educational Resources Information Center

    Barker, Tommy G.

    This curriculum guide is designed to assist junior high schools industrial arts teachers in planning new courses and revising existing courses in plastics technology. Addressed in the individual units of the guide are the following topics: introduction to production technology; history and development of plastics; safety; youth leadership,…

  16. Expressive suppression and neural responsiveness to nonverbal affective cues.

    PubMed

    Petrican, Raluca; Rosenbaum, R Shayna; Grady, Cheryl

    2015-10-01

    Optimal social functioning occasionally requires concealment of one's emotions in order to meet one's immediate goals and environmental demands. However, because emotions serve an important communicative function, their habitual suppression disrupts the flow of social exchanges and, thus, incurs significant interpersonal costs. Evidence is accruing that the disruption in social interactions, linked to habitual expressive suppression use, stems not only from intrapersonal, but also from interpersonal causes, since the suppressors' restricted affective displays reportedly inhibit their interlocutors' emotionally expressive behaviors. However, expressive suppression use is not known to lead to clinically significant social impairments. One explanation may be that over the lifespan, individuals who habitually suppress their emotions come to compensate for their interlocutors' restrained expressive behaviors by developing an increased sensitivity to nonverbal affective cues. To probe this issue, the present study used functional magnetic resonance imaging (fMRI) to scan healthy older women while they viewed silent videos of a male social target displaying nonverbal emotional behavior, together with a brief verbal description of the accompanying context, and then judged the target's affect. As predicted, perceivers who reported greater habitual use of expressive suppression showed increased neural processing of nonverbal affective cues. This effect appeared to be coordinated in a top-down manner via cognitive control. Greater neural processing of nonverbal cues among perceivers who habitually suppress their emotions was linked to increased ventral striatum activity, suggestive of increased reward value/personal relevance ascribed to emotionally expressive nonverbal behaviors. These findings thus provide neural evidence broadly consistent with the hypothesized link between habitual use of expressive suppression and compensatory development of increased responsiveness to

  17. Expressive suppression and neural responsiveness to nonverbal affective cues.

    PubMed

    Petrican, Raluca; Rosenbaum, R Shayna; Grady, Cheryl

    2015-10-01

    Optimal social functioning occasionally requires concealment of one's emotions in order to meet one's immediate goals and environmental demands. However, because emotions serve an important communicative function, their habitual suppression disrupts the flow of social exchanges and, thus, incurs significant interpersonal costs. Evidence is accruing that the disruption in social interactions, linked to habitual expressive suppression use, stems not only from intrapersonal, but also from interpersonal causes, since the suppressors' restricted affective displays reportedly inhibit their interlocutors' emotionally expressive behaviors. However, expressive suppression use is not known to lead to clinically significant social impairments. One explanation may be that over the lifespan, individuals who habitually suppress their emotions come to compensate for their interlocutors' restrained expressive behaviors by developing an increased sensitivity to nonverbal affective cues. To probe this issue, the present study used functional magnetic resonance imaging (fMRI) to scan healthy older women while they viewed silent videos of a male social target displaying nonverbal emotional behavior, together with a brief verbal description of the accompanying context, and then judged the target's affect. As predicted, perceivers who reported greater habitual use of expressive suppression showed increased neural processing of nonverbal affective cues. This effect appeared to be coordinated in a top-down manner via cognitive control. Greater neural processing of nonverbal cues among perceivers who habitually suppress their emotions was linked to increased ventral striatum activity, suggestive of increased reward value/personal relevance ascribed to emotionally expressive nonverbal behaviors. These findings thus provide neural evidence broadly consistent with the hypothesized link between habitual use of expressive suppression and compensatory development of increased responsiveness to

  18. Expressive suppression and neural responsiveness to nonverbal affective cues

    PubMed Central

    Petrican, Raluca; Rosenbaum, R. Shayna; Grady, Cheryl

    2016-01-01

    Optimal social functioning occasionally requires concealment of one’s emotions in order to meet one’s immediate goals and environmental demands. However, because emotions serve an important communicative function, their habitual suppression disrupts the flow of social exchanges and, thus, incurs significant interpersonal costs. Evidence is accruing that the disruption in social interactions, linked to habitual expressive suppression use, stems not only from intrapersonal, but also from interpersonal causes, since the suppressors’ restricted affective displays reportedly inhibit their interlocutors’ emotionally expressive behaviors. However, expressive suppression use is not known to lead to clinically significant social impairments. One explanation may be that over the lifespan, individuals who habitually suppress their emotions come to compensate for their interlocutors’ restrained expressive behaviors by developing an increased sensitivity to nonverbal affective cues. To probe this issue, the present study used functional magnetic resonance imaging (fMRI) to scan healthy older women while they viewed silent videos of a male social target displaying nonverbal emotional behavior, together with a brief verbal description of the accompanying context, and then judged the target’s affect. As predicted, perceivers who reported greater habitual use of expressive suppression showed increased neural processing of nonverbal affective cues. This effect appeared to be coordinated in a top-down manner via cognitive control. Greater neural processing of nonverbal cues among perceivers who habitually suppress their emotions was linked to increased ventral striatum activity, suggestive of increased reward value/personal relevance ascribed to emotionally expressive nonverbal behaviors. These findings thus provide neural evidence broadly consistent with the hypothesized link between habitual use of expressive suppression and compensatory development of increased

  19. Habit learning and memory in mammals: behavioral and neural characteristics.

    PubMed

    Gasbarri, Antonella; Pompili, Assunta; Packard, Mark G; Tomaz, Carlos

    2014-10-01

    Goal-direct behavior and habit learning represent two forms of instrumental learning; whereas the former is rapidly acquired and regulated by its outcome, the latter is reflexive, elicited by antecedent stimuli rather than their consequences. Habit learning can be generally defined as the acquisition of associations between stimuli and responses. Habits are acquired via experience-dependent plasticity, occurring repeatedly over the course of days or years and becoming remarkably fixed. The distinction between habit learning, as a product of a procedural learning brain system, and a declarative learning system for encoding facts and episodes is based on the hypothesis that memory is composed of multiple systems that have distinct neuroanatomy and operating principles. Here we review recent research analyzing the main behavioral and neural characteristics of habit learning. In particular, we focus on the distinction between goal-directed and habitual behavior, and describe the brain areas and neurotransmitters systems involved in habit learning. The emotional modulation of habit learning in rodents and primates is reviewed, and the implications of habit learning in psychopathology are briefly described. PMID:24981854

  20. Human and Rodent Homologies in Action Control: Corticostriatal Determinants of Goal-Directed and Habitual Action

    PubMed Central

    Balleine, Bernard W; O'Doherty, John P

    2010-01-01

    Recent behavioral studies in both humans and rodents have found evidence that performance in decision-making tasks depends on two different learning processes; one encoding the relationship between actions and their consequences and a second involving the formation of stimulus–response associations. These learning processes are thought to govern goal-directed and habitual actions, respectively, and have been found to depend on homologous corticostriatal networks in these species. Thus, recent research using comparable behavioral tasks in both humans and rats has implicated homologous regions of cortex (medial prefrontal cortex/medial orbital cortex in humans and prelimbic cortex in rats) and of dorsal striatum (anterior caudate in humans and dorsomedial striatum in rats) in goal-directed action and in the control of habitual actions (posterior lateral putamen in humans and dorsolateral striatum in rats). These learning processes have been argued to be antagonistic or competing because their control over performance appears to be all or none. Nevertheless, evidence has started to accumulate suggesting that they may at times compete and at others cooperate in the selection and subsequent evaluation of actions necessary for normal choice performance. It appears likely that cooperation or competition between these sources of action control depends not only on local interactions in dorsal striatum but also on the cortico-basal ganglia network within which the striatum is embedded and that mediates the integration of learning with basic motivational and emotional processes. The neural basis of the integration of learning and motivation in choice and decision-making is still controversial and we review some recent hypotheses relating to this issue. PMID:19776734

  1. Stressor and glucocorticoid-dependent induction of the immediate early gene kruppel-like factor 9: implications for neural development and plasticity.

    PubMed

    Bonett, Ronald M; Hu, Fang; Bagamasbad, Pia; Denver, Robert J

    2009-04-01

    Krüppel-like factor 9 (KLF9) is a thyroid hormone-induced, immediate early gene implicated in neural development in vertebrates. We analyzed stressor and glucocorticoid (GC)-dependent regulation of KLF9 expression in the brain of the frog Xenopus laevis, and investigated a possible role for KLF9 in neuronal differentiation. Exposure to shaking/confinement stressor increased plasma corticosterone (CORT) concentration, and KLF9 immunoreactivity in several brain regions, which included the medial amygdala and bed nucleus of the stria terminalis, anterior preoptic area (homologous to the mammalian paraventricular nucleus), and optic tectum (homologous to the mammalian superior colliculus). The stressor-induced KLF9 mRNA expression in the brain was blocked by pretreatment with the GC receptor antagonist RU486, or mimicked by injection of CORT. Treatment with CORT also caused a rapid and dose-dependent increase in KLF9 mRNA in X. laevis XTC-2 cells that was resistant to inhibition of protein synthesis. The action of CORT on KLF9 expression in XTC-2 cells was blocked by RU486, but not by the mineralocorticoid receptor antagonist spironolactone. To test for functional consequences of up-regulation of KLF9, we introduced a KLF9 expression plasmid into living tadpole brain by electroporation-mediated gene transfer. Forced expression of KLF9 in tadpole brain caused an increase in Golgi-stained cells, reflective of neuronal differentiation/maturation. Our results support that KLF9 is a direct, GC receptor target gene that is induced by stress, and functions as an intermediary in the actions of GCs on brain gene expression and neuronal structure.

  2. A Constructive Neural-Network Approach to Modeling Psychological Development

    ERIC Educational Resources Information Center

    Shultz, Thomas R.

    2012-01-01

    This article reviews a particular computational modeling approach to the study of psychological development--that of constructive neural networks. This approach is applied to a variety of developmental domains and issues, including Piagetian tasks, shift learning, language acquisition, number comparison, habituation of visual attention, concept…

  3. Long-term habituation to food in obese and nonobese women123

    PubMed Central

    Carr, Katelyn A; Cavanaugh, Meghan D; Paluch, Rocco A; Bouton, Mark E

    2011-01-01

    Background: Habituation is a form of learning in which repeated exposure to a stimulus leads to a decrease in responding. Eating involves repeated presentation of the same food stimulus in a meal, and habituation is reliably observed within a meal such that faster rates of habituation are associated with less energy intake. It is possible that repeated presentation of the same food over days will lead to long-term habituation, such that subjects habituate to foods repeated over meals. However, no research on long-term habituation to food in humans has been conducted. Objective: The current study was designed to assess long-term habituation in 16 obese and 16 nonobese premenopausal women. Design: Obese and nonobese women (aged 20–50 y) were randomly assigned to receive a macaroni and cheese meal presented 5 times, either daily for 1 wk or once per week for 5 wk. Results: In both obese and nonobese women, daily presentation of food resulted in faster habituation and less energy intake than did once-weekly presentation of food. Conclusions: Long-term habituation was observed when the same food was presented at daily meals but not when presented once weekly for 5 wk. These results provide the first evidence of long-term habituation to food in women and show that memory of food over daily meals can increase the rate of habituation and reduce energy intake. This trial was registered at clinicaltrials.gov as NCT01208870. PMID:21593492

  4. Slow rates of habituation predict greater zBMI gains over 12 months in lean children

    PubMed Central

    Epstein, Leonard H.; Robinson, Jodie L.; Roemmich, James N.; Marusewski, Angela

    2011-01-01

    Slow rates of habituation are related to greater energy intake, and cross-sectionally to body weight. The present study is designed to assess whether slow rates of habituation are prospectively related to zBMI change over a 12 month period in 66 lean 8–12 year-old children, and whether the rate of habituation is a stable behavioral phenotype. Results showed slower rates of habituation predicted greater zBMI change, controlling for child sex, age, initial zBMI, dietary awareness and minority status. In addition, the rate of habituation was stable over the year of observation. These data suggest that slow rates of habituation may be a risk factor for weight gain and the development of obesity. Future research is needed to understand the mechanism for this effect, and assess whether the habituation phenotype interacts with other behavioral phenotypes, such as food reinforcement, to influence increases in zBMI. PMID:21741020

  5. Reimann's “Habitual Hyperthermia” Responding to Hormone Therapy

    PubMed Central

    Yang, Otto O.; Currier, Judith S.

    2016-01-01

    A 25-year-old woman presented with fever of unknown origin, exhibiting malaise and low-grade fevers in evenings. These fevers exhibited a pattern of starting mid-menstrual cycle with resolution around the onset of menses, matching a pattern of “habitual hyperthermia” reported by H. Reimann in the 1930s. Extensive workup was unremarkable, and the fevers improved on oral synthetic estrogen and progesterone therapy. PMID:27800522

  6. Resistance to extinction following habituation to behaviourally disruptive novel stimuli.

    PubMed

    Haggbloom, S J; Brewer, V R

    1989-11-01

    Three experiments tested the prediction, derived from generalized frustration theory (Amsel, 1972), that habituation to behaviourally disruptive stimuli increases resistance to extinction in the runway. In each experiment, rats received initial consistent reinforcement (CRF) training and then either continued CRF (Groups C), partial reinforcement (PRF) training (Groups P), or CRF accompanied by presentations of a novel tactile, tone, or obstacle stimulus (Groups D) in Experiments 1-3, respectively. PRF increased resistance to extinction whether non-reinforcement disrupted behaviour (Experiment 1) or not (Experiments 2 and 3). The tactile and obstacle stimuli very substantially disrupted behaviour, and the tone produced a modest disruption of behaviour. All subjects habituated to the disruptive effects of these stimuli, but Group D was not more resistant to extinction than Group C in any experiment. The results suggest that non-reinforcement has unique stimulus properties, a consequence of which is that habituation to other sources of disruptive stimulation does not promote responding to non-reinforcement in extinction.

  7. [Etiology and management of habitual constipation (author's transl)].

    PubMed

    Franken, F H

    1977-02-01

    Habitual constipation is present, if defecation occurs because of prolonged retention of stool in the colon less than three times per week. Motility of the intestine is increased in these cases, not decreased as has been thought for long time. Several factors of modern civilization favor habitual constipation, e.g. nutrition devoided of poorly digestible ingredients, and lack of physical exercise. The diagnosis of habitual constipation should only be made after careful exclusion of all organic causes by means of x-ray and endoscopic examination. Therapy is conservative in most cases. The diet ought to be rich in indigestible ingredients; eating and defecation habits have to be adapted to a regular pattern. Hydrophilic colloid laxatives may be used as well as in a limited extent laxatives effective on an osmotic basis. Laxatives acting more drastically or being effective upon contact with the intestinal mucosa are not suited for long-term therapy of constipation. Surgery is indicated only in a few cases.

  8. Beyond extinction: Habituation eliminates conditioned skin conductance across contexts.

    PubMed

    Haesen, Kim; Vervliet, Bram

    2015-12-01

    A marked signature of fear extinction is its vulnerability for relapse. Here, we departed from the standard extinction principle and examined the ability of habituation to reduce conditioned fear reactions and prevent relapse. In a human fear conditioning paradigm, we first established one visual stimulus as a signal for an impending aversive electrical stimulation, while another visual stimulus was never followed by this stimulation. Next, the screen color changed and participants were exposed to either the visual stimuli without electrical stimulation (extinction treatment) or to the electrical stimulation without the visual stimuli (habituation treatment). Finally, the screen color changed back and the two visual stimuli were tested. Verbal ratings showed a return of conditioned shock-expectancy in the two groups, while skin conductance reactivity showed conditioned discrimination following exposures to the visual stimuli, but not following exposures to the electrical stimulation. We conclude that a habituation treatment outperforms an extinction treatment, and that shock-expectancy and skin conductance can dissociate under some conditions.

  9. Neurogenomic mechanisms of social plasticity.

    PubMed

    Cardoso, Sara D; Teles, Magda C; Oliveira, Rui F

    2015-01-01

    Group-living animals must adjust the expression of their social behaviour to changes in their social environment and to transitions between life-history stages, and this social plasticity can be seen as an adaptive trait that can be under positive selection when changes in the environment outpace the rate of genetic evolutionary change. Here, we propose a conceptual framework for understanding the neuromolecular mechanisms of social plasticity. According to this framework, social plasticity is achieved by rewiring or by biochemically switching nodes of a neural network underlying social behaviour in response to perceived social information. Therefore, at the molecular level, it depends on the social regulation of gene expression, so that different genomic and epigenetic states of this brain network correspond to different behavioural states, and the switches between states are orchestrated by signalling pathways that interface the social environment and the genotype. Different types of social plasticity can be recognized based on the observed patterns of inter- versus intra-individual occurrence, time scale and reversibility. It is proposed that these different types of social plasticity rely on different proximate mechanisms at the physiological, neural and genomic level. PMID:25568461

  10. A simplified preparation for relating cellular events to behavior: contribution of LE and unidentified siphon sensory neurons to mediation and habituation of the Aplysia gill- and siphon-withdrawal reflex.

    PubMed

    Frost, L; Kaplan, S W; Cohen, T E; Henzi, V; Kandel, E R; Hawkins, R D

    1997-04-15

    We have begun to analyze several elementary forms of learning in a simple preparation consisting of the isolated mantle organs and abdominal ganglion of Aplysia. Previous studies suggested that plasticity at siphon sensory neuron synapses contributes to habituation and dishabituation of the gill- and siphon-withdrawal reflex in this preparation. We next wished to identify the sensory neurons that participate in the reflex and examine their plasticity more directly. To investigate the contribution of the LE siphon mechanosensory cells, we recorded from them and gill or siphon motor neurons during the same siphon stimulation that has been used in behavioral experiments in this preparation. Our results indicate that the LE cells make a substantial contribution to the evoked response in the motor neurons under these conditions, but they suggest that other as yet unidentified siphon sensory neurons with lower thresholds and shorter latencies also contribute. In addition, we find that homosynaptic depression of monosynaptic postsynaptic potentials (PSPs) from LE sensory cells makes an important contribution to habituation of the response in the motor neurons. To investigate plasticity of PSPs from the unidentified sensory neurons, we recorded the PSP that was produced in a motor neuron by water-movement stimulation of the siphon, which does not cause firing of LE cells. Our results suggest that PSPs from the unidentified sensory neurons and the LE neurons undergo similar plasticity during habituation and dishabituation training. These results support the idea that plasticity at synapses of both LE and unidentified sensory neurons contributes to habituation and dishabituation of the reflex response in this preparation.

  11. Spatiotemporal Computations of an Excitable and Plastic Brain: Neuronal Plasticity Leads to Noise-Robust and Noise-Constructive Computations

    PubMed Central

    Toutounji, Hazem; Pipa, Gordon

    2014-01-01

    It is a long-established fact that neuronal plasticity occupies the central role in generating neural function and computation. Nevertheless, no unifying account exists of how neurons in a recurrent cortical network learn to compute on temporally and spatially extended stimuli. However, these stimuli constitute the norm, rather than the exception, of the brain's input. Here, we introduce a geometric theory of learning spatiotemporal computations through neuronal plasticity. To that end, we rigorously formulate the problem of neural representations as a relation in space between stimulus-induced neural activity and the asymptotic dynamics of excitable cortical networks. Backed up by computer simulations and numerical analysis, we show that two canonical and widely spread forms of neuronal plasticity, that is, spike-timing-dependent synaptic plasticity and intrinsic plasticity, are both necessary for creating neural representations, such that these computations become realizable. Interestingly, the effects of these forms of plasticity on the emerging neural code relate to properties necessary for both combating and utilizing noise. The neural dynamics also exhibits features of the most likely stimulus in the network's spontaneous activity. These properties of the spatiotemporal neural code resulting from plasticity, having their grounding in nature, further consolidate the biological relevance of our findings. PMID:24651447

  12. High stimulus specificity characterizes anti-predator habituation under natural conditions.

    PubMed

    Hemmi, Jan M; Merkle, Tobias

    2009-12-22

    Habituation is one of the most fundamental learning processes that allow animals to adapt to dynamic environments. It is ubiquitous and often thought of as a simple form of non-associative learning. Very little is known, though, about the rules that govern habituation and their significance under natural conditions. Questions about how animals incorporate habituation into their daily behaviour and how they can assure only to habituate to non-relevant stimuli are still unanswered. Animals under threat of predation should be particularly selective about which stimuli they habituate to, since ignoring a real threat could be fatal. In this study, we tested the response of fiddler crabs, Uca vomeris, to repeatedly approaching dummy predators to find out whether these animals habituate to potential predators and to test the selectivity of the habituation process. The crabs habituated to model predators, even though they were confronted with real predators during the same habituation process. They showed remarkable selectivity towards the stimulus: a simple change in the approach distance of the stimulus led to a recovery in their responses. The results strongly indicate that in the context of predator avoidance, habituation under natural conditions is highly selective and a stimulus is not defined just by its current sensory signature, but also its spatio-temporal history.

  13. Loss of EphA4 impairs short-term spatial recognition memory performance and locomotor habituation.

    PubMed

    Willi, R; Winter, C; Wieske, F; Kempf, A; Yee, B K; Schwab, M E; Singer, P

    2012-11-01

    EphA4 receptor (EphA4) tyrosine kinase is an important regulator of central nervous system development and synaptic plasticity in the mature brain, but its relevance to the control of normal behavior remains largely unexplored. This study is the first attempt to obtain a behavioral profile of constitutive homozygous and heterozygous EphA4 knockout mice. A deficit in locomotor habituation in the open field, impairment in spatial recognition in the Y-maze and reduced probability of spatial spontaneous alternation in the T-maze were identified in homozygous EphA4(-/-) mice, while heterozygo us EphA4(+/-) mice appeared normal on these tests in comparison with wild-type (WT) controls. The multiple phenotypes observed in EphA4(-/-) mice might stem from an underlying deficit in habituation learning, reflecting an elementary form of nonassociative learning that is in contrast to Pavlovian associative learning, which appeared unaffected by EphA4 disruption. A deficit in motor coordination on the accelerating rotarod was also demonstrated only in EphA4(-/-) mice--a finding in keeping with the presence of abnormal gait in EphA4(-/-) mice--although they were able to improve performance over training. There was no evidence for substantial changes in major neurochemical markers in various brain regions rich in EphA4 as shown by post-mortem analysis. This excludes the possibility of major neurochemical compensation in the brain of EphA4(-/-) mice. In summary, we have demonstrated for the first time the behavioral significance of EphA4 disruption, supporting further investigation of EphA4 as a possible target for behavioral interventions where habituation deficits are prominent.

  14. Prediction of thermal strains in fibre reinforced plastic matrix by discretisation of the temperature exposure history

    NASA Astrophysics Data System (ADS)

    Ngoy, E. K.

    2016-07-01

    Prediction of environmental effects on fibre reinforced plastics habitually is made difficult due to the complex variability of the natural service environment. This paper suggests a method to predict thermal strain distribution over the material lifetime by discretisation of the exposure history. Laboratory results show a high correlation between predicted and experimentally measured strain distribution

  15. Response, use and habituation to a mouse house in C57BL/6J and BALB/c mice.

    PubMed

    Wirz, Annarita; Mandillo, Silvia; D'Amato, Francesca R; Giuliani, Alessandro; Riviello, M Cristina

    2015-01-01

    Animal welfare depends on the possibility to express species-specific behaviours and can be strongly compromised in socially and environmentally deprived conditions. Nesting materials and refuges are very important resources to express these behaviours and should be considered as housing supplementation items. We evaluated the effects of one item of housing supplementation in standard settings in laboratory mice. C57BL/6JOlaHsd (B6) and BALB/cOlaHsd (BALB) young male and female mice, upon arrival, were housed in groups of four in standard laboratory cages and after 10 days of acclimatization, a red transparent plastic triangular-shaped Mouse House™ was introduced into half of the home cages. Animals with or without a mouse house were observed in various contexts for more than one month. Body weight gain and food intake, home cage behaviours, emotionality and response to standard cage changing procedures were evaluated. The presence of a mouse house in the home cage did not interfere with main developmental and behavioural parameters or emotionality of BALB and B6 male and female mice compared with controls. Both strains habituated to the mouse house in about a week, but made use of it differently, with BALB mice using the house more than the B6 strain. Our results suggest that mice habituated to the mouse house rather quickly without disrupting their home cage activities. Scientists can thus be encouraged to use mouse houses, also in view of the implementation of the EU Directive (2010/63/EU).

  16. Response, use and habituation to a mouse house in C57BL/6J and BALB/c mice

    PubMed Central

    WIRZ, Annarita; MANDILLO, Silvia; D’AMATO, Francesca R.; GIULIANI, Alessandro; RIVIELLO, M. Cristina

    2015-01-01

    Animal welfare depends on the possibility to express species-specific behaviours and can be strongly compromised in socially and environmentally deprived conditions. Nesting materials and refuges are very important resources to express these behaviours and should be considered as housing supplementation items. We evaluated the effects of one item of housing supplementation in standard settings in laboratory mice. C57BL/6JOlaHsd (B6) and BALB/cOlaHsd (BALB) young male and female mice, upon arrival, were housed in groups of four in standard laboratory cages and after 10 days of acclimatization, a red transparent plastic triangular-shaped Mouse House™ was introduced into half of the home cages. Animals with or without a mouse house were observed in various contexts for more than one month. Body weight gain and food intake, home cage behaviours, emotionality and response to standard cage changing procedures were evaluated. The presence of a mouse house in the home cage did not interfere with main developmental and behavioural parameters or emotionality of BALB and B6 male and female mice compared with controls. Both strains habituated to the mouse house in about a week, but made use of it differently, with BALB mice using the house more than the B6 strain. Our results suggest that mice habituated to the mouse house rather quickly without disrupting their home cage activities. Scientists can thus be encouraged to use mouse houses, also in view of the implementation of the EU Directive (2010/63/EU). PMID:25854626

  17. Motion sickness and otolith sensitivity - A pilot study of habituation to linear acceleration

    NASA Technical Reports Server (NTRS)

    Potvin, A. R.; Sadoff, M.; Billingham, J.

    1977-01-01

    Astronauts, particularly in Skylab flights, experienced varying degrees of motion sickness lasting 3-5 days. One possible mechanism for this motion sickness adaptation is believed to be a reduction in otolith sensitivity with an attendant reduction in sensory conflict. In an attempt to determine if this hypothesis is valid, a ground-based pilot study was conducted on a vertical linear accelerator. The extent of habituation to accelerations which initially produced motion sickness was evaluated, along with the possible value of habituation training to minimize the space motion sickness problem. Results showed that habituation occurred for 6 of the 8 subjects tested. However, in tests designed to measure dynamic and static otolith function, no significant differences between pre- and post-habituation tests were observed. Cross habituation effects to a standard Coriolis acceleration test were not significant. It is unlikely that ground-based pre-habituation to linear accelerations of the type examined would alter susceptibility to space motion sickness.

  18. Habituation of the acoustic and the tactile startle responses in mice: two independent sensory processes.

    PubMed

    Pilz, Peter K D; Carl, Thomas D; Plappert, Claudia F

    2004-10-01

    To test whether habituation is specific to the stimulus modality, the authors analyzed cross-habituation between the tactile startle response' (TSR) and the acoustic startle response (ASR). The acoustic artifacts of airpuffs used to elicit the TSR were reduced by using a silencer and were effectively masked by background noise of 90-100 dB sound-pressure level. ASR was elicited by 14-kHz tones. TSR and ASR habituated in DBA and BALB mice: both the TSR and ASR habituated to a greater extent in DBA mice than in BALB mice. In both strains, habituation of the TSR did not generalize to the ASR, and vice versa. From this, the authors concluded that habituation of startle is located in the sensory afferent branches of the pathway.

  19. Prism adaptation contrasts perceptual habituation for repetitive somatosensory stimuli.

    PubMed

    Torta, D M; Tatu, M K; Cotroneo, D; Alamia, A; Folegatti, A; Trojan, J

    2016-03-01

    Prism adaptation (PA) is a non-invasive procedure that requires performing a visuo-motor pointing task while wearing prism goggles inducing a visual displacement of the pointed target. This procedure involves a reorganization of sensorimotor coordination, and induces long-lasting effects on numerous higher-order cognitive functions in healthy volunteers and neglect patients. Prismatic displacement (PD) of the visual field can be induced when prisms are worn but no sensorimotor task is required. In this case, it is unlikely that any subsequent reorganization takes place. The effects of PD are short-lived in the sense that they last as long as prisms are worn. In this study we aimed, to the best of our knowledge for the first time, at investigating whether PA and PD induce changes in the perception of intensity of nociceptive and non- nociceptive somatosensory stimuli. We induced, in healthy volunteers, PD (experiment 1), or PA (experiment 2) and asked participants to rate the intensity of the stimuli applied to the hand undergoing the visuo-proprioceptive conflict (experiment 1) or adaptation (experiment 2). Our results indicate that: 1) the visuo-proprioceptive conflict induced by PD does not reduce the perceived intensity of the stimuli, 2) PA prevents perceptual habituation for both nociceptive and non-nociceptive somatosensory stimuli. Moreover, to investigate the possible underlying mechanisms of the effects of PA we conducted a third experiment in which stimuli were applied both at the adapted and the non-adapted hand. In line with the results of experiment 2, we found that perceptual habituation was prevented for stimuli applied onto the adapted hand. Moreover, we observed the same finding for stimuli applied onto the non-adapted hand. This result suggests that the detention of habituation is not merely driven by changes in spatial attention allocation. Taken together, these data indicate that prisms can affect the perceived intensity of somatosensory stimuli

  20. Do black ducks and wood ducks habituate to aircraft disturbance?

    USGS Publications Warehouse

    Conomy, J.T.; Dubovsky, J.A.; Collazo, J.A.; Fleming, W.J.

    1998-01-01

    Requests to increase military aircraft activity in some training facilities in the United States have raised the need to determine if waterfowl and other wildlife are adversely affected by aircraft disturbance. We hypothesized that habituation was a possible proximate factor influencing the low proportion of free-ranging ducks reacting to military aircraft activities in a training range in coastal North Carolina during winters 1991 and 1992. To test this hypothesis, we subjected captive, wild-strain American black ducks (Anas rubripes) and wood ducks (Aix sponsa) to actual and simulated activities of jet aircraft. In the first experiment, we placed black ducks in an enclosure near the center of aircraft activities on Piney Island, a military aircraft target range in coastal North Carolina. The proportion of times black ducks reacted (e.g., alert posture, fleeing response) to visual and auditory aircraft activity decreased from 38 to 6% during the first 17 days of confinement. Response rates remained stable at 5.8% thereafter. In the second experiment, black ducks and wood ducks were exposed to 6 different recordings of jet noise. The proportion of times black ducks reacted to noise decreased (P 0.05) in time-activity budgets of black ducks between pre-exposure to noise and 24 hr after first exposure. Unlike black ducks, wood duck responses to jet noise did not decrease uniformly among experimental groups following initial exposure to noise (P = 0.01). We conclude that initial exposure to aircraft noise elicits behavioral responses from black ducks and wood ducks. With continued exposure of aircraft noise, black ducks may become habituated. However, wood ducks did not exhibit the same pattern of response, suggesting that the ability of waterfowl to habituate to aircraft noise may be species specific.

  1. Testing for odor discrimination and habituation in mice.

    PubMed

    Arbuckle, Erin P; Smith, Gregory D; Gomez, Maribel C; Lugo, Joaquin N

    2015-05-05

    This video demonstrates a technique to establish the presence of a normally functioning olfactory system in a mouse. The test helps determine whether the mouse can discriminate between non-social odors and social odors, whether the mouse habituates to a repeatedly presented odor, and whether the mouse demonstrates dishabituation when presented with a novel odor. Since many social behavior tests measure the experimental animal's response to a familiar or novel mouse, false positives can be avoided by establishing that the animals can detect and discriminate between social odors. There are similar considerations in learning tests such as fear conditioning that use odor to create a novel environment or olfactory cues as an associative stimulus. Deficits in the olfactory system would impair the ability to distinguish between contexts and to form an association with an olfactory cue during fear conditioning. In the odor habitation/dishabituation test, the mouse is repeatedly presented with several odors. Each odor is presented three times for two minutes. The investigator records the sniffing time directed towards the odor as the measurement of olfactory responsiveness. A typical mouse shows a decrease in response to the odor over repeated presentations (habituation). The experimenter then presents a novel odor that elicits increased sniffing towards the new odor (dishabituation). After repeated presentation of the novel odor the animal again shows habituation. This protocol involves the presentation of water, two or more non-social odors, and two social odors. In addition to reducing experimental confounds, this test can provide information on the function of the olfactory systems of new knockout, knock-in, and conditional knockout mouse lines.

  2. Stimulant-induced adaptations in neostriatal matrix and striosome systems: transiting from instrumental responding to habitual behavior in drug addiction.

    PubMed

    Canales, Juan J

    2005-03-01

    Converging evidence indicates that repeated exposure to motor stimulants such as cocaine and amphetamine produces marked alterations in network responsiveness of striatal neurons to subsequent challenge with the same stimulant drug. Such alterations, which correlate with persistent patterns of repetitive behavior, associate with distinct compartmental changes in the neostriatum. Striatal matrix system neurons undergo "silencing" following repeated drug challenges, allowing striosome system neurons to exhibit preferential activation. Matrix neurons are innervated by sensory and motor areas of neocortex and are activated in the course of on-going, adaptive behavior. Inactivation of matrix neurons by chronic stimulant exposure may therefore constrain sensorimotor and cognitive processing. In turn, the striosomes are anatomically connected through re-entrant loops with limbic prefrontal and allocortical structures, such as anterior cingulate cortex, orbital frontal cortex, and basolateral amygdala, all of which play a part in stimulant-induced reinforcement and relapse to drug-taking. Moreover, functional evidence links striosome system neurons, which are responsible for providing inhibitory regulatory feedback to midbrain dopamine neurons, with reinforcement-based processes. In considering such evidence, we postulate that recurrent matrix inactivation and recruitment of striosome-based pathways by chronic stimulant exposure represent neural end-points of the transit from action-outcome associative behavior to conditioned habitual responding. Within this theoretical framework, habitual behavior can be elicited by both interoceptive cues and exteroceptive conditioned stimuli to promote the automatic execution of learned responses.

  3. Differential engagement of the ventromedial prefrontal cortex by goal-directed and habitual behavior toward food pictures in humans.

    PubMed

    de Wit, Sanne; Corlett, Philip R; Aitken, Mike R; Dickinson, Anthony; Fletcher, Paul C

    2009-09-01

    According to dual-system accounts, instrumental learning is supported by both a goal-directed and a habitual system. Although behavioral control by the goal-directed system, through outcome-action associations, dominates with moderate training, stimulus-response associations are thought to form concurrently in the habit system. It is therefore challenging to isolate the neural substrate of the goal-directed system in neuroimaging research with healthy human volunteers. Recently, however, de Wit et al. (2007) developed an instrumental discrimination task that distinguishes between goal-directed and habit-based responding. In this task, cues are congruent, unrelated, or incongruent with subsequent outcomes. Whereas performance on congruent and control trials can be supported by both the goal-directed and habitual system, performance on the incongruent discrimination relies solely on the habit system. In the present study, we used this task with healthy participants undergoing functional magnetic resonance imaging to demonstrate that engagement of the goal-directed system during learning is reflected in increased activity in the ventromedial prefrontal cortex. Moreover, using a subsequent outcome devaluation manipulation, we show that this area is involved in guiding decision making when goal values change, even in the absence of external cues to guide performance. We can therefore exclude a purely Pavlovian account of ventromedial prefrontal function and unequivocally demonstrate its involvement in the acquisition as well as deployment of goal-directed knowledge.

  4. Steady-state visual evoked potentials in the low frequency range in migraine: a study of habituation and variability phenomena.

    PubMed

    de Tommaso, Marina; Stramaglia, Sebastiano; Schoffelen, Jan Mathijs; Guido, Marco; Libro, Giuseppe; Losito, Luciana; Sciruicchio, Vittorio; Sardaro, Michele; Pellicoro, Mario; Puca, Franco Michele

    2003-08-01

    Previous studies have revealed that migraine patients display an increased photic driving to flash stimuli in the medium frequency range. The aim of this study was to perform a topographic analysis of steady-state visual evoked potentials (SVEPs) in the low frequency range (3-9 Hz), evaluating the temporal behaviour of the F1 amplitude by investigating habituation and variability phenomena. The main component of SVEPs, the F1, demonstrated an increased amplitude in several channels at 3 Hz. Behaviour of F1 amplitude was rather variable over time, and the wavelet-transform standard deviation was increased in migraine patients at a low stimulus rate. The discriminative value of the F1 mean amplitude and variability index, tested by both an artificial neural network classifier and a support vector machine, were high according to both methods. The increased photic driving in migraine should be subtended by a more generic abnormality of visual reactivity instead of a selective impairment of a visual subsystem. Temporal behaviour of SVEPs is not influenced by a clear tendency to habituation, but the F1 amplitude seemed to change in a complex way, which is better described by variability phenomena. An increased variability in response to flicker stimuli in migraine patients could be interpreted as an overactive regulation mechanism, prone to instability and consequently to headache attacks, whether spontaneous or triggered. PMID:12919718

  5. Steady-state visual evoked potentials in the low frequency range in migraine: a study of habituation and variability phenomena.

    PubMed

    de Tommaso, Marina; Stramaglia, Sebastiano; Schoffelen, Jan Mathijs; Guido, Marco; Libro, Giuseppe; Losito, Luciana; Sciruicchio, Vittorio; Sardaro, Michele; Pellicoro, Mario; Puca, Franco Michele

    2003-08-01

    Previous studies have revealed that migraine patients display an increased photic driving to flash stimuli in the medium frequency range. The aim of this study was to perform a topographic analysis of steady-state visual evoked potentials (SVEPs) in the low frequency range (3-9 Hz), evaluating the temporal behaviour of the F1 amplitude by investigating habituation and variability phenomena. The main component of SVEPs, the F1, demonstrated an increased amplitude in several channels at 3 Hz. Behaviour of F1 amplitude was rather variable over time, and the wavelet-transform standard deviation was increased in migraine patients at a low stimulus rate. The discriminative value of the F1 mean amplitude and variability index, tested by both an artificial neural network classifier and a support vector machine, were high according to both methods. The increased photic driving in migraine should be subtended by a more generic abnormality of visual reactivity instead of a selective impairment of a visual subsystem. Temporal behaviour of SVEPs is not influenced by a clear tendency to habituation, but the F1 amplitude seemed to change in a complex way, which is better described by variability phenomena. An increased variability in response to flicker stimuli in migraine patients could be interpreted as an overactive regulation mechanism, prone to instability and consequently to headache attacks, whether spontaneous or triggered.

  6. Plastic condoms.

    PubMed

    1968-01-01

    Only simple equipment, simple technology and low initial capital investment are needed in their manufacture. The condoms can be made by people who were previously unskilled or only semi-skilled workers. Plastic condoms differ from those made of latex rubber in that the nature of the plastic film allows unlimited shelf-life. Also, the plastic has a higher degree of lubricity than latex rubber; if there is a demand for extra lubrication in a particular market, this can be provided. Because the plastic is inert, these condoms need not be packaged in hermetically sealed containers. All these attributes make it possible to put these condoms on the distributors' shelves in developing countries competitively with rubber condoms. The shape of the plastic condom is based on that of the lamb caecum, which has long been used as luxury-type condom. The plastic condom is made from plastic film (ethylene ethyl acrilate) of 0.001 inch (0.0254 mm.) thickness. In addition, a rubber ring is provided and sealed into the base of the condom for retention during coitus. The advantage of the plastic condom design and the equipment on which it is made is that production can be carried out either in labour-intensive economy or with varying degrees of mechanization and automation. The uniform, finished condom if made using previously untrained workers. Training of workers can be done in a matter of hours on the two machines which are needed to produce and test the condoms. The plastic film is provided on a double wound roll, and condom blanks are prepared by means of a heat-sealing die on the stamping machine. The rubber rings are united to the condom blanks on an assembly machine, which consists of a mandrel and heat-sealing equipment to seal the rubber ring to the base of the condom. Built into the assembly machine is a simple air-testing apparatus that can detect the smallest pinhole flaw in a condom. The manufacturing process is completed by unravelling the condom from the assembly

  7. Plasticity of Cortical Excitatory-Inhibitory Balance

    PubMed Central

    Froemke, Robert C.

    2015-01-01

    Synapses are highly plastic and are modified by changes in patterns of neural activity or sensory experience. Plasticity of cortical excitatory synapses is thought to be important for learning and memory, leading to alterations in sensory representations and cognitive maps. However, these changes must be coordinated across other synapses within local circuits to preserve neural coding schemes and the organization of excitatory and inhibitory inputs, i.e., excitatory-inhibitory balance. Recent studies indicate that inhibitory synapses are also plastic and are controlled directly by a large number of neuromodulators, particularly during episodes of learning. Many modulators transiently alter excitatory-inhibitory balance by decreasing inhibition, and thus disinhibition has emerged as a major mechanism by which neuromodulation might enable long-term synaptic modifications naturally. This review examines the relationships between neuromodulation and synaptic plasticity, focusing on the induction of long-term changes that collectively enhance cortical excitatory-inhibitory balance for improving perception and behavior. PMID:25897875

  8. Prolonged repeated acupuncture stimulation induces habituation effects in pain-related brain areas: an FMRI study.

    PubMed

    Li, Chuanfu; Yang, Jun; Park, Kyungmo; Wu, Hongli; Hu, Sheng; Zhang, Wei; Bu, Junjie; Xu, Chunsheng; Qiu, Bensheng; Zhang, Xiaochu

    2014-01-01

    Most previous studies of brain responses to acupuncture were designed to investigate the acupuncture instant effect while the cumulative effect that should be more important in clinical practice has seldom been discussed. In this study, the neural basis of the acupuncture cumulative effect was analyzed. For this experiment, forty healthy volunteers were recruited, in which more than 40 minutes of repeated acupuncture stimulation was implemented at acupoint Zhusanli (ST36). Three runs of acupuncture fMRI datasets were acquired, with each run consisting of two blocks of acupuncture stimulation. Besides general linear model (GLM) analysis, the cumulative effects of acupuncture were analyzed with analysis of covariance (ANCOVA) to find the association between the brain response and the cumulative duration of acupuncture stimulation in each stimulation block. The experimental results showed that the brain response in the initial stage was the strongest although the brain response to acupuncture was time-variant. In particular, the brain areas that were activated in the first block and the brain areas that demonstrated cumulative effects in the course of repeated acupuncture stimulation overlapped in the pain-related areas, including the bilateral middle cingulate cortex, the bilateral paracentral lobule, the SII, and the right thalamus. Furthermore, the cumulative effects demonstrated bimodal characteristics, i.e. the brain response was positive at the beginning, and became negative at the end. It was suggested that the cumulative effect of repeated acupuncture stimulation was consistent with the characteristic of habituation effects. This finding may explain the neurophysiologic mechanism underlying acupuncture analgesia.

  9. Compensatory plasticity: time matters.

    PubMed

    Lazzouni, Latifa; Lepore, Franco

    2014-01-01

    Plasticity in the human and animal brain is the rule, the base for development, and the way to deal effectively with the environment for making the most efficient use of all the senses. When the brain is deprived of one sensory modality, plasticity becomes compensatory: the exception that invalidates the general loss hypothesis giving the opportunity of effective change. Sensory deprivation comes with massive alterations in brain structure and function, behavioral outcomes, and neural interactions. Blind individuals do as good as the sighted and even more, show superior abilities in auditory, tactile and olfactory processing. This behavioral enhancement is accompanied with changes in occipital cortex function, where visual areas at different levels become responsive to non-visual information. The intact senses are in general used more efficiently in the blind but are also used more exclusively. New findings are disentangling these two aspects of compensatory plasticity. What is due to visual deprivation and what is dependent on the extended use of spared modalities? The latter seems to contribute highly to compensatory changes in the congenitally blind. Short-term deprivation through the use of blindfolds shows that cortical excitability of the visual cortex is likely to show rapid modulatory changes after few minutes of light deprivation and therefore changes are possible in adulthood. However, reorganization remains more pronounced in the congenitally blind. Cortico-cortical pathways between visual areas and the areas of preserved sensory modalities are inhibited in the presence of vision, but are unmasked after loss of vision or blindfolding as a mechanism likely to drive cross-modal information to the deafferented visual cortex. The development of specialized higher order visual pathways independently from early sensory experience is likely to preserve their function and switch to the intact modalities. Plasticity in the blind is also accompanied with

  10. Cosmetic Plastic Surgery Statistics

    MedlinePlus

    2014 Cosmetic Plastic Surgery Statistics Cosmetic Procedure Trends 2014 Plastic Surgery Statistics Report Please credit the AMERICAN SOCIETY OF PLASTIC SURGEONS when citing statistical data or using ...

  11. Plastics Technician.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document contains 16 units to consider for use in a tech prep competency profile for the occupation of plastics technician. All the units listed will not necessarily apply to every situation or tech prep consortium, nor will all the competencies within each unit be appropriate. Several units appear within each specific occupation and would…

  12. Exploratory activity and habituation of Drosophila in confined domains

    NASA Astrophysics Data System (ADS)

    Soibam, B.; Chen, L.; Roman, G. W.; Gunaratne, G. H.

    2014-09-01

    Animals use locomotion to find food, shelter, and escape routes as well as to locate predators, competitors, and mates. Thus, locomotion is related to many behavioral traits, and can be used to characterize these more complex facets of behavior. Exploratory behaviors are random and need to be assessed through stochastic analysis. By comparing ensembles of trajectories from Drosophila and a model animal, we identify a pair of principles that govern the stochastic motion of a specific species. The first depends on local cues and quantify directional persistence, i.e., the propensity of an animal to maintain direction; the second, its attraction to walls, is relevant for exploration in confined arenas. Statistical properties of exploratory activity in several types of arenas can be computed from these principles. A pair of spiral arenas are designed to demonstrate that centrophobicity, or fear of the center of an arena, is not a fundamental feature of exploration. xxxx We provide evidence to show that the decay in an animal's activity following its introduction into a novel arena is correlated to its familiarity with the arena. We define two measures, coverage and habituation, to quantify familiarity. It is found that the relationship between activity and coverage is independent of the arena size. Finally, we use an analysis of exploration of mutant species to infer that in Drosophila, habituation relies on visual cues.

  13. Habituation of salivation and motivated responding for food in children.

    PubMed

    Epstein, Leonard H; Saad, Frances G; Handley, Elizabeth A; Roemmich, James N; Hawk, Larry W; McSweeney, Frances K

    2003-12-01

    Repeated presentation of food cues results in habituation in adults, as demonstrated by a decrement in salivary responding that is reversed by presenting a new food cue in adults. Food reinforced behavior in animals shows the same pattern of responding, with a decrease in responding to obtain the food, followed by a recovery of responding when a new food is presented. The present study assessed whether children would show the same pattern of a decrement of food reinforced responding followed by recovery of responding when a new food is presented for both salivation and food reinforcement tasks. Subjects were assigned to one of two groups that differed in the trial that the new food stimulus was presented to ensure recovery was specific to the introduction of the new food stimulus. In the salivation task, subjects were provided repeated olfactory presentations of a cheeseburger with apple pie as the new food stimulus, while in the food reinforcement task subjects worked for the opportunity to consume a cheeseburger, followed by the opportunity to work for consumption of apple pie. Subjects in both groups showed a decrement in salivary and food reinforced responding to repeated food cues followed by immediate recovery of responding on the trial when a new food was presented. Subjects increased their energy intake by over 30% in the food reinforcement task when a new food was presented. These results are consistent with the general process theory of motivation that suggests that changes in food reinforced responding may be due in part to habituation.

  14. Habituation of salivation and motivated responding for food in children.

    PubMed

    Epstein, Leonard H; Saad, Frances G; Handley, Elizabeth A; Roemmich, James N; Hawk, Larry W; McSweeney, Frances K

    2003-12-01

    Repeated presentation of food cues results in habituation in adults, as demonstrated by a decrement in salivary responding that is reversed by presenting a new food cue in adults. Food reinforced behavior in animals shows the same pattern of responding, with a decrease in responding to obtain the food, followed by a recovery of responding when a new food is presented. The present study assessed whether children would show the same pattern of a decrement of food reinforced responding followed by recovery of responding when a new food is presented for both salivation and food reinforcement tasks. Subjects were assigned to one of two groups that differed in the trial that the new food stimulus was presented to ensure recovery was specific to the introduction of the new food stimulus. In the salivation task, subjects were provided repeated olfactory presentations of a cheeseburger with apple pie as the new food stimulus, while in the food reinforcement task subjects worked for the opportunity to consume a cheeseburger, followed by the opportunity to work for consumption of apple pie. Subjects in both groups showed a decrement in salivary and food reinforced responding to repeated food cues followed by immediate recovery of responding on the trial when a new food was presented. Subjects increased their energy intake by over 30% in the food reinforcement task when a new food was presented. These results are consistent with the general process theory of motivation that suggests that changes in food reinforced responding may be due in part to habituation. PMID:14637327

  15. The effect of antimotion sickness drugs on habituation to motion

    NASA Technical Reports Server (NTRS)

    Wood, C. D.; Manno, J. E.; Manno, B. R.; Odenheimer, R. C.; Bairnsfather, L. E.

    1986-01-01

    The mechanism which allows for increased exposure to motion and accelerates habituation is investigated. The responses of 12 male and female subjects between 18-30 years rotated once a day for 5 days on the Contraves Goerz rotating chair after receiving placebo, 10 mg d-amphetamine, 0.6 mg scopolamine with 5 mg d-amphetamine, and 1.0 mg scopolamine are studied. It is observed that with placebo the subjects performed 48 more head movements than untreated subjects, 118 more movements with d-amphetamine, 176 more with 0.6 mg scopolamine with d-amphetamine, and 186 more with 1.0 scopolamine. The data reveal that exposure to rotation increases tolerance from 88 head movements on day 2 to 159 on day 4 at 17.4 rpm and with placebo; 96 to 186 at 19.9 rpm with 10 mg d-amphetamine; 111 to 273 at 20.2 rpm with scopolamine with d-amphetamine, and 141 to 279 at 22.4 rpm with 1.0 mg scopolamine. It is noted that a combination of cholinergic blocking and norepinephrine activation action is most effective in preventing the development of motion sickness and habituation is due to the greater exposure to vestibular simulation permitted by the drugs.

  16. Habituation and the reinforcing effectiveness of visual stimuli.

    PubMed

    Lloyd, David R; Gancarz, Amy M; Ashrafioun, Lisham; Kausch, Michael A; Richards, Jerry B

    2012-10-01

    The term "sensory reinforcer" has been used to refer to sensory stimuli (e.g. light onset) that are primary reinforcers in order to differentiate them from other more biologically important primary reinforcers (e.g. food and water). Acquisition of snout poke responding for a visual stimulus (5 s light onset) with fixed ratio 1 (FR 1), variable-interval 1 min (VI 1 min), or variable-interval 6 min (VI 6 min) schedules of reinforcement was tested in three groups of rats (n=8/group). The VI 6 min schedule of reinforcement produced a higher response rate than the FR 1 or VI 1 min schedules of visual stimulus reinforcement. One explanation for greater responding on the VI 6 min schedule relative to the FR 1 and VI 1 min schedules is that the reinforcing effectiveness of light onset habituated more rapidly in the FR 1 and VI 1 min groups as compared to the VI 6 min group. The inverse relationship between response rate and the rate of visual stimulus reinforcement is opposite to results from studies with biologically important reinforcers which indicate a positive relationship between response and reinforcement rate. Rapid habituation of reinforcing effectiveness may be a fundamental characteristic of sensory reinforcers that differentiates them from biologically important reinforcers, which are required to maintain homeostatic balance.

  17. Pan-Neuronal Expression of APL-1, an APP-Related Protein, Disrupts Olfactory, Gustatory, and Touch Plasticity in Caenorhabditis elegans

    PubMed Central

    Ewald, Collin Y.; Cheng, Ruby; Tolen, Lana; Shah, Vishal; Gillani, Aneela; Nasrin, Afsana

    2012-01-01

    Patients with Alzheimer's disease show age-related cognitive decline. Postmortem autopsy of their brains shows the presence of large numbers of senile plaques, whose major component is the β-amyloid peptide. The β-amyloid peptide is a cleavage product of the amyloid precursor protein (APP). In addition to the neurodegeneration associated with β-amyloid aggregation in Alzheimer's disease patients, mutations in APP in mammalian model organisms have also been shown to disrupt several behaviors independent of visible amyloid plaque formation. However, the pathways in which APP function are unknown and difficult to unravel in mammals. Here we show that pan-neuronal expression of APL-1, the Caenorhabditis elegans ortholog of APP, disrupts several behaviors, such as olfactory and gustatory learning behavior and touch habituation. These behaviors are mediated by distinct neural circuits, suggesting a broad impact of APL-1 on sensory plasticity in C. elegans. Furthermore, we found that disruption of these three behaviors requires activity of the TGFβ pathway and reduced activity of the insulin pathway. These results suggest pathways and molecular components that may underlie behavioral plasticity in mammals and in patients with Alzheimer's disease. PMID:22836251

  18. What causes aberrant salience in schizophrenia? A role for impaired short-term habituation and the GRIA1 (GluA1) AMPA receptor subunit

    PubMed Central

    Barkus, C; Sanderson, DJ; Rawlins, JNP; Walton, ME; Harrison, PJ; Bannerman, DM

    2014-01-01

    The GRIA1 locus, encoding the GluA1 (also known as GluRA or GluR1) AMPA glutamate receptor subunit, shows genome-wide association to schizophrenia. As well as extending the evidence that glutamatergic abnormalities play a key role in the disorder, this finding draws attention to the behavioural phenotype of Gria1 knockout mice. These mice show deficits in short-term habituation. Importantly, under some conditions the attention being paid to a recently presented neutral stimulus can actually increase rather than decrease (sensitization). We propose that this mouse phenotype represents a cause of aberrant salience and, in turn, that aberrant salience (and the resulting positive symptoms) in schizophrenia may arise, at least in part, from a glutamatergic genetic predisposition and a deficit in short-term habituation. This proposal links an established risk gene with a psychological process central to psychosis, and is supported by findings of comparable deficits in short-term habituation in mice lacking the NMDAR receptor subunit Grin2a (which also shows association to schizophrenia). Since aberrant salience is primarily a dopaminergic phenomenon, the model supports the view that the dopaminergic abnormalities can be downstream of a glutamatergic aetiology. Finally, we suggest that, as illustrated here, the real value of genetically modified mice is not as ‘models of schizophrenia’, but as experimental tools which can link genomic discoveries with psychological processes, and help elucidate the underlying neural mechanisms. PMID:25224260

  19. Characterizing the associative content of brain structures involved in habitual and goal-directed actions in humans: a multivariate FMRI study.

    PubMed

    McNamee, Daniel; Liljeholm, Mimi; Zika, Ondrej; O'Doherty, John P

    2015-03-01

    While there is accumulating evidence for the existence of distinct neural systems supporting goal-directed and habitual action selection in the mammalian brain, much less is known about the nature of the information being processed in these different brain regions. Associative learning theory predicts that brain systems involved in habitual control, such as the dorsolateral striatum, should contain stimulus and response information only, but not outcome information, while regions involved in goal-directed action, such as ventromedial and dorsolateral prefrontal cortex and dorsomedial striatum, should be involved in processing information about outcomes as well as stimuli and responses. To test this prediction, human participants underwent fMRI while engaging in a binary choice task designed to enable the separate identification of these different representations with a multivariate classification analysis approach. Consistent with our predictions, the dorsolateral striatum contained information about responses but not outcomes at the time of an initial stimulus, while the regions implicated in goal-directed action selection contained information about both responses and outcomes. These findings suggest that differential contributions of these regions to habitual and goal-directed behavioral control may depend in part on basic differences in the type of information that these regions have access to at the time of decision making. PMID:25740507

  20. Nicotine and Methamphetamine Disrupt Habituation of Sensory Reinforcer Effectiveness in Male Rats

    PubMed Central

    Lloyd, David R.; Hausknecht, Kathryn A.; Richards, Jerry B.

    2014-01-01

    The reinforcing effectiveness of a sensory stimulus such as light-onset rapidly habituates (Lloyd, Gancarz, Ashrafioun, Kausch, & Richards, 2012). According to memory-based theories, habituation occurs if a memory exists for perceived stimulation, and dishabituation occurs if a memory does not exist and the stimulation is “unexpected.” According to Redgrave and Gurney (2006), unexpected response-contingent sensory stimuli increase phasic firing of dopamine neurons, providing a sensory error signal that reflects the difference between perceived and expected stimuli. Together, memory-based theories of habituation and the sensory error signal hypothesis predict a disruption (slowing) of habituation rate by novel response-contingent sensory stimulation or by artificial increases in dopamine neurotransmission by stimulant drugs. To test these predictions, we examined the effects of stimulant drugs on both the operant level of responding (snout-poking) and operant responding for a sensory reinforcer (light-onset) presented according to a fixed ratio 1 schedule. Robust within-session decreases in responding indicating habituation were observed. The effects of stimulant drugs (saline, n = 10; nicotine, 0.40 mg/kg, n = 10; and methamphetamine, 0.75 mg/kg, n = 9) on habituation in rats were determined. Nicotine was found to decrease habituation rate and did not affect response rate, while methamphetamine decreased habituation rate and increased response rate. In addition, introduction of a novel visual stimulus reinforcer decreased habituation rate and increased responding. These findings show that habituation of reinforcer effectiveness modulates operant responding for sensory reinforcers, and that stimulant drugs may disrupt normally occurring habituation of reinforcer effectiveness by increasing dopamine neurotransmission. PMID:24708147

  1. Nicotine and methamphetamine disrupt habituation of sensory reinforcer effectiveness in male rats.

    PubMed

    Lloyd, David R; Hausknecht, Kathryn A; Richards, Jerry B

    2014-04-01

    The reinforcing effectiveness of a sensory stimulus such as light-onset rapidly habituates (Lloyd, Gancarz, Ashrafioun, Kausch, & Richards, 2012). According to memory-based theories, habituation occurs if a memory exists for perceived stimulation, and dishabituation occurs if a memory does not exist and the stimulation is "unexpected." According to Redgrave and Gurney (2006), unexpected response-contingent sensory stimuli increase phasic firing of dopamine neurons, providing a sensory error signal that reflects the difference between perceived and expected stimuli. Together, memory-based theories of habituation and the sensory error signal hypothesis predict a disruption (slowing) of habituation rate by novel response-contingent sensory stimulation or by artificial increases in dopamine neurotransmission by stimulant drugs. To test these predictions, we examined the effects of stimulant drugs on both the operant level of responding (snout-poking) and operant responding for a sensory reinforcer (light-onset) presented according to a fixed ratio 1 schedule. Robust within-session decreases in responding indicating habituation were observed. The effects of stimulant drugs (saline, n = 10; nicotine, 0.40 mg/kg, n = 10; and methamphetamine, 0.75 mg/kg, n = 9) on habituation in rats were determined. Nicotine was found to decrease habituation rate and did not affect response rate, while methamphetamine decreased habituation rate and increased response rate. In addition, introduction of a novel visual stimulus reinforcer decreased habituation rate and increased responding. These findings show that habituation of reinforcer effectiveness modulates operant responding for sensory reinforcers, and that stimulant drugs may disrupt normally occurring habituation of reinforcer effectiveness by increasing dopamine neurotransmission.

  2. Self-organization of neural networks

    NASA Astrophysics Data System (ADS)

    Clark, John W.; Winston, Jeffrey V.; Rafelski, Johann

    1984-05-01

    The plastic development of a neural-network model operating autonomously in discrete time is described by the temporal modification of interneuronal coupling strengths according to momentary neural activity. A simple algorithm (“brainwashing”) is found which, applied to nets with initially quasirandom connectivity, leads to model networks with properties conductive to the simulation of memory and learning phenomena.

  3. Neuronal plasticity: adaptation and readaptation to the environment of space.

    PubMed

    Correia, M J

    1998-11-01

    While there have been few documented permanent neurological changes resulting from space travel, there is a growing literature which suggests that neural plasticity sometimes occurs within peripheral and central vestibular pathways during and following spaceflight. This plasticity probably has adaptive value within the context of the space environment, but it can be maladaptive upon return to the terrestrial environment. Fortunately, the maladaptive responses resulting from neuronal plasticity diminish following return to earth. However, the literature suggests that the longer the space travel, the more difficult the readaptation. With the possibility of extended space voyages and extended stays on board the international space station, it seems worthwhile to review examples of plastic vestibular responses and changes in the underlying neural substrates. Studies and facilities needed for space station investigation of plastic changes in the neural substrates are suggested.

  4. Synaptic plasticity functions in an organic electrochemical transistor

    NASA Astrophysics Data System (ADS)

    Gkoupidenis, Paschalis; Schaefer, Nathan; Strakosas, Xenofon; Fairfield, Jessamyn A.; Malliaras, George G.

    2015-12-01

    Synaptic plasticity functions play a crucial role in the transmission of neural signals in the brain. Short-term plasticity is required for the transmission, encoding, and filtering of the neural signal, whereas long-term plasticity establishes more permanent changes in neural microcircuitry and thus underlies memory and learning. The realization of bioinspired circuits that can actually mimic signal processing in the brain demands the reproduction of both short- and long-term aspects of synaptic plasticity in a single device. Here, we demonstrate the implementation of neuromorphic functions similar to biological memory, such as short- to long-term memory transition, in non-volatile organic electrochemical transistors (OECTs). Depending on the training of the OECT, the device displays either short- or long-term plasticity, therefore, exhibiting non von Neumann characteristics with merged processing and storing functionalities. These results are a first step towards the implementation of organic-based neuromorphic circuits.

  5. Neuronal plasticity: adaptation and readaptation to the environment of space

    NASA Technical Reports Server (NTRS)

    Correia, M. J.

    1998-01-01

    While there have been few documented permanent neurological changes resulting from space travel, there is a growing literature which suggests that neural plasticity sometimes occurs within peripheral and central vestibular pathways during and following spaceflight. This plasticity probably has adaptive value within the context of the space environment, but it can be maladaptive upon return to the terrestrial environment. Fortunately, the maladaptive responses resulting from neuronal plasticity diminish following return to earth. However, the literature suggests that the longer the space travel, the more difficult the readaptation. With the possibility of extended space voyages and extended stays on board the international space station, it seems worthwhile to review examples of plastic vestibular responses and changes in the underlying neural substrates. Studies and facilities needed for space station investigation of plastic changes in the neural substrates are suggested. Copyright 1998 Elsevier Science B.V.

  6. Plastic bronchitis.

    PubMed

    Singhi, Anil Kumar; Vinoth, Bharathi; Kuruvilla, Sarah; Sivakumar, Kothandam

    2015-01-01

    Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics. They are ominous with poor prognosis. Sometimes, infection or airway reactivity may provoke cast bronchitis as a two-step insult on a vulnerable vascular bed. In such instances, aggressive management leads to longer survival. This report of cast bronchitis discusses its current understanding. PMID:26556975

  7. Sensitization and habituation of motivated behavior in overweight and non-overweight children

    PubMed Central

    Epstein, Leonard H.; Robinson, Jodie L.; Temple, Jennifer L.; Roemmich, James N.; Marusewski, Angela; Nadbrzuch, Rachel

    2008-01-01

    The rate of habituation to food is inversely related to energy intake, and overweight children may habituate slower to food and consume more energy. This study compared patterns of sensitization, as defined by an initial increase in operant or motivated responding for food, and habituation, defined by gradual reduction in responding, for macaroni and cheese and pizza in overweight and non-overweight 8−12 year-old children. Non-overweight children habituated faster to both foods than overweight children (p = 0.03). All children recovered motivated responding for a new food (chocolate). Overweight children consumed more energy than non-overweight children (p = 0.0004). Children who showed a sensitization in responding consumed more food (p = 0.001), and sensitization moderated the effect of overweight on habituation, with slower habituation for overweight children who sensitized (p < 0.0001). This study replicates previous data on overweight/non-overweight differences in habituation of food and of energy intake, and provides new information that individual differences in sensitization and habituation of motivated responding to food cues may be associated with a sustained motivation to eat, resulting in greater energy intake. PMID:19649135

  8. Relationship between Young Children's Habitual Computer Use and Influencing Variables on Socio-Emotional Development

    ERIC Educational Resources Information Center

    Seo, Hyun Ah; Chun, Hui Young; Jwa, Seung Hwa; Choi, Mi Hyun

    2011-01-01

    This study investigates the relationship between young children's habitual computer use and influencing variables on socio-emotional development. The participants were 179 five-year-old children. The Internet Addiction Scale for Young Children (IASYC) was used to identify children with high and low levels of habituation to computer use. The data…

  9. Dishabituation in "Aplysia" Can Involve Either Reversal of Habituation or Superimposed Sensitization

    ERIC Educational Resources Information Center

    Kandel, Eric R.; Hawkins, Robert D.; Cohen, Tracey E.

    2006-01-01

    Dishabituation has been thought to be due either to reversal of the process of habituation or to a second process equivalent to sensitization superimposed on habituation. One way to address this question is by testing whether dishabituation and sensitization can be dissociated. Previous studies using this approach in "Aplysia" have come to…

  10. Auditory Habituation in the Fetus and Neonate: An fMEG Study

    ERIC Educational Resources Information Center

    Muenssinger, Jana; Matuz, Tamara; Schleger, Franziska; Kiefer-Schmidt, Isabelle; Goelz, Rangmar; Wacker-Gussmann, Annette; Birbaumer, Niels; Preissl, Hubert

    2013-01-01

    Habituation--the most basic form of learning--is used to evaluate central nervous system (CNS) maturation and to detect abnormalities in fetal brain development. In the current study, habituation, stimulus specificity and dishabituation of auditory evoked responses were measured in fetuses and newborns using fetal magnetoencephalography (fMEG). An…

  11. Visual Habituation and Preference for Novelty in Five-Week-Old Infants.

    ERIC Educational Resources Information Center

    Hunter, Michael A.; Ames, Elinor W.

    This study was designed to determine if the failure of previous investigations to find habituation and response to novelty in infants younger than 2 months of age was because the stimuli used were too complex or because a constant number of trials rather than an individual criterion of habituation was used. A total of 24 infants between 5 and 6…

  12. Infant Behavior and Development in Relation to Fetal Movement and Habituation.

    ERIC Educational Resources Information Center

    Madison, Lynda S.; And Others

    1986-01-01

    Evaluated the relation between fetal activity and postnatal behavior and development by measuring the amount of fetal movement occurring in response to stimulation and the number of stimulus applications necessary for habituation. Preliminary evidence suggests that fetal rate of habituation predicts some aspects of infant behavior and development…

  13. Bourdieu Knew More than How to Play Tennis! An Empirically Based Discussion of Habituation and Reflexivity

    ERIC Educational Resources Information Center

    Strandbu, Åse; Steen-Johnsen, Kari

    2014-01-01

    This paper explores the role of reflexivity in habituation by contrasting the learning of aerobics and basketball with the acquisition of gendered bodily skills. The discussion is inspired by the paper "So, how did Bourdieu learn to play tennis? Habitus, consciousness and habituation," by Noble and Watkins (2003), which represents a…

  14. Sensitization and habituation of motivated behavior in overweight and non-overweight children.

    PubMed

    Epstein, Leonard H; Robinson, Jodie L; Temple, Jennifer L; Roemmich, James N; Marusewski, Angela; Nadbrzuch, Rachel

    2008-08-01

    The rate of habituation to food is inversely related to energy intake, and overweight children may habituate slower to food and consume more energy. This study compared patterns of sensitization, as defined by an initial increase in operant or motivated responding for food, and habituation, defined by gradual reduction in responding, for macaroni and cheese and pizza in overweight and non-overweight 8-12 year-old children. Non-overweight children habituated faster to both foods than overweight children (p = 0.03). All children recovered motivated responding for a new food (chocolate). Overweight children consumed more energy than non-overweight children (p = 0.0004). Children who showed a sensitization in responding consumed more food (p = 0.001), and sensitization moderated the effect of overweight on habituation, with slower habituation for overweight children who sensitized (p < 0.0001). This study replicates previous data on overweight/non-overweight differences in habituation of food and of energy intake, and provides new information that individual differences in sensitization and habituation of motivated responding to food cues may be associated with a sustained motivation to eat, resulting in greater energy intake.

  15. Decrease in excitability of LG following habituation of the crayfish escape reaction.

    PubMed

    Araki, Makoto; Nagayama, Toshiki

    2005-05-01

    Crayfish escapes from threatening stimuli to the abdomen by tailflipping upwards and forwards. This lateral giant (LG)-mediated escape reaction habituates readily upon repetitive sensory stimulation. Using an isolated abdominal nerve cord preparation, we have analyzed the change in LG activity by applying additional sensory stimulation after different periods following habituation to characterize the retention of LG habituation. Results show that the LG mediated response habituates more quickly, but the retention time is shorter, as repetitive sensory stimulation is applied at progressively shorter inter-stimulus time intervals. The spike response of LG recovers quickly, within several minutes after habituation, but they fail to spike when an additional stimulus is applied after specific long periods following habituation. The critical period of the delay for this decrease in excitability of LG is dependent on the inter-stimulus time interval of the initial repetitive stimulus. As the inter-stimulus interval became longer, the delay needed for decrease in excitability became shorter. Furthermore, the local injection of 10(-6) mol l-1 octopamine into the neuropil just following habituation promotes the achievement of decrease in excitability. No effects were observed when 10(-6) mol l-1 serotonin and tyramine were injected. These results suggested octopamine promotes decrease in excitability of LG following habituation.

  16. "Habituation": A Method for Cultivating "Starting Points" in the Ethical Life

    ERIC Educational Resources Information Center

    Kerr, Jeannie

    2011-01-01

    The Aristotelian concept of habituation is receiving mounting and warranted interest in educational circles, but has also been subject to different lines of interpretation and critique. In this article, I bring forward Aristotle's words on habituation, and then clarify the two lines of interpretation that have developed in the contemporary…

  17. Lack of contextual modulation of habituated neuroendocrine responses to repeated audiogenic stress

    PubMed Central

    Nyhuis, Tara J.; Sasse, Sarah K.; Masini, Cher V.; Day, Heidi E.W.; Campeau, Serge

    2010-01-01

    Exposure to stress reliably activates the hypothalamo-pituitary-adrenocortical (HPA) axis response in rodents, which is significantly reduced (habituated) following repeated exposures. In the current study, it was first established that HPA axis response habituation to repeated loud noise lasted for at least four weeks in rats. In the next Experiment, a contextual extinction procedure following repeated loud noise exposures failed to restore the habituated HPA axis response. Although an additional study indicated some recovery of responses when the context was modified on a test day following habituation, this effect could be mostly attributed to the familiarity with the contextual cues. A final study confirmed that rats could distinguish between the contexts employed and further indicated that context pre-exposures reduce acute HPA axis responses to loud noise. These studies therefore provide no support for the hypothesis that contextual cues regulate HPA axis response habituation. PMID:21038933

  18. The comparator model of infant visual habituation and dishabituation: recent insights.

    PubMed

    Kavšek, Michael

    2013-12-01

    Current knowledge of the perceptual and cognitive abilities in infancy is largely based on the visual habituation-dishabituation method. According to the comparator model [e.g., Sokolov (1963a) Perception and the conditioned reflex. Oxford: Pergamon Press], habituation refers to stimulus encoding and dishabituation refers to discriminatory memory performance. The review also describes the dual-process theory and the attention disengagement approach. The dual-process theory points to the impact of natural stimulus preferences on habituation-dishabituation processes. The attention disengagement approach emphasizes the contribution of the ability to shift the attention away from a stimulus. Moreover, arguments for the cognitive interpretation of visual habituation and dishabituations are discussed. These arguments are provided by physiological studies and by research on interindividual differences. Overall, the review shows that current research supports the comparator model. It emphasizes that the investigation of habituation and dishabituation expands our understanding of visual attention processes in infants.

  19. Joint Loads in Marsupial Ankles Reflect Habitual Bipedalism versus Quadrupedalism

    PubMed Central

    Carlson, Kristian J.; Jashashvili, Tea; Houghton, Kimberley; Westaway, Michael C.; Patel, Biren A.

    2013-01-01

    Joint surfaces of limb bones are loaded in compression by reaction forces generated from body weight and musculotendon complexes bridging them. In general, joints of eutherian mammals have regions of high radiodensity subchondral bone that are better at resisting compressive forces than low radiodensity subchondral bone. Identifying similar form-function relationships between subchondral radiodensity distribution and joint load distribution within the marsupial postcranium, in addition to providing a richer understanding of marsupial functional morphology, can serve as a phylogenetic control in evaluating analogous relationships within eutherian mammals. Where commonalities are established across phylogenetic borders, unifying principles in mammalian physiology, morphology, and behavior can be identified. Here, we assess subchondral radiodensity patterns in distal tibiae of several marsupial taxa characterized by different habitual activities (e.g., locomotion). Computed tomography scanning, maximum intensity projection maps, and pixel counting were used to quantify radiodensity in 41 distal tibiae of bipedal (5 species), arboreal quadrupedal (4 species), and terrestrial quadrupedal (5 species) marsupials. Bipeds (Macropus and Wallabia) exhibit more expansive areas of high radiodensity in the distal tibia than arboreal (Dendrolagus, Phascolarctos, and Trichosurus) or terrestrial quadrupeds (Sarcophilus, Thylacinus, Lasiorhinus, and Vombatus), which may reflect the former carrying body weight only through the hind limbs. Arboreal quadrupeds exhibit smallest areas of high radiodensity, though they differ non-significantly from terrestrial quadrupeds. This could indicate slightly more compliant gaits by arboreal quadrupeds compared to terrestrial quadrupeds. The observed radiodensity patterns in marsupial tibiae, though their statistical differences disappear when controlling for phylogeny, corroborate previously documented patterns in primates and xenarthrans

  20. Joint loads in marsupial ankles reflect habitual bipedalism versus quadrupedalism.

    PubMed

    Carlson, Kristian J; Jashashvili, Tea; Houghton, Kimberley; Westaway, Michael C; Patel, Biren A

    2013-01-01

    Joint surfaces of limb bones are loaded in compression by reaction forces generated from body weight and musculotendon complexes bridging them. In general, joints of eutherian mammals have regions of high radiodensity subchondral bone that are better at resisting compressive forces than low radiodensity subchondral bone. Identifying similar form-function relationships between subchondral radiodensity distribution and joint load distribution within the marsupial postcranium, in addition to providing a richer understanding of marsupial functional morphology, can serve as a phylogenetic control in evaluating analogous relationships within eutherian mammals. Where commonalities are established across phylogenetic borders, unifying principles in mammalian physiology, morphology, and behavior can be identified. Here, we assess subchondral radiodensity patterns in distal tibiae of several marsupial taxa characterized by different habitual activities (e.g., locomotion). Computed tomography scanning, maximum intensity projection maps, and pixel counting were used to quantify radiodensity in 41 distal tibiae of bipedal (5 species), arboreal quadrupedal (4 species), and terrestrial quadrupedal (5 species) marsupials. Bipeds (Macropus and Wallabia) exhibit more expansive areas of high radiodensity in the distal tibia than arboreal (Dendrolagus, Phascolarctos, and Trichosurus) or terrestrial quadrupeds (Sarcophilus, Thylacinus, Lasiorhinus, and Vombatus), which may reflect the former carrying body weight only through the hind limbs. Arboreal quadrupeds exhibit smallest areas of high radiodensity, though they differ non-significantly from terrestrial quadrupeds. This could indicate slightly more compliant gaits by arboreal quadrupeds compared to terrestrial quadrupeds. The observed radiodensity patterns in marsupial tibiae, though their statistical differences disappear when controlling for phylogeny, corroborate previously documented patterns in primates and xenarthrans

  1. Habitual intake of fruit juice predicts central blood pressure.

    PubMed

    Pase, Matthew P; Grima, Natalie; Cockerell, Robyn; Pipingas, Andrew

    2015-01-01

    Despite a common perception that fruit juice is healthy, fruit juice contains high amounts of naturally occurring sugar without the fibre content of the whole fruit. Frequent fruit juice consumption may therefore contribute to excessive sugar consumption typical of the Western society. Although excess sugar intake is associated with high blood pressure (BP), the association between habitual fruit juice consumption and BP is unclear. The present study investigated the association of fruit juice consumption with brachial and central (aortic) BP in 160 community dwelling adults. Habitual fruit juice consumption was measured using a 12 month dietary recall questionnaire. On the same day, brachial BP was measured and central (aortic) BP was estimated through radial artery applanation. Frequency of fruit juice consumption was classified as rare, occasional or daily. Those who consumed fruit juice daily, versus rarely or occasionally, had significantly higher central systolic BP (F (2, 134) = 6.09, p <0.01), central pulse pressure (F (2, 134) = 4.16, p <0.05), central augmentation pressure (F (2, 134) = 5.98, p <0.01) and central augmentation index (F (2, 134) = 3.29, p <0.05) as well as lower pulse pressure amplification (F (2, 134) = 4.36, p <0.05). There were no differences in brachial BP. Central systolic BP was 3-4 mmHg higher for those who consumed fruit juice daily rather than rarely or occasionally. In conclusion, more frequent fruit juice consumption was associated with higher central BPs.

  2. Optogenetics and synaptic plasticity.

    PubMed

    Xie, Yu-feng; Jackson, Michael F; Macdonald, John F

    2013-11-01

    The intricate and complex interaction between different populations of neurons in the brain has imposed limits on our ability to gain detailed understanding of synaptic transmission and its integration when employing classical electrophysiological approaches. Indeed, electrical field stimulation delivered via traditional microelectrodes does not permit the targeted, precise and selective control of neuronal activity amongst a varied population of neurons and their inputs (eg, cholinergic, dopaminergic or glutamatergic neurons). Recently established optogenetic techniques overcome these limitations allowing precise control of the target neuron populations, which is essential for the elucidation of the neural substrates underlying complex animal behaviors. Indeed, by introducing light-activated channels (ie, microbial opsin genes) into specific neuronal populations, optogenetics enables non-invasive optical control of specific neurons with milliseconds precision. These approaches can readily be applied to freely behaving live animals. Recently there is increased interests in utilizing optogenetics tools to understand synaptic plasticity and learning/memory. Here, we summarize recent progress in applying optogenetics in in the study of synaptic plasticity.

  3. Heterosynaptic Plasticity: Multiple Mechanisms and Multiple Roles

    PubMed Central

    Chistiakova, Marina; Bannon, Nicholas M.; Bazhenov, Maxim; Volgushev, Maxim

    2016-01-01

    Plasticity is a universal property of synapses. It is expressed in a variety of forms mediated by a multitude of mechanisms. Here we consider two broad kinds of plasticity that differ in their requirement for presynaptic activity during the induction. Homosynaptic plasticity occurs at synapses that were active during the induction. It is also called input specific or associative, and it is governed by Hebbian-type learning rules. Heterosynaptic plasticity can be induced by episodes of strong postsynaptic activity also at synapses that were not active during the induction, thus making any synapse at a cell a target to heterosynaptic changes. Both forms can be induced by typical protocols used for plasticity induction and operate on the same time scales but have differential computational properties and play different roles in learning systems. Homosynaptic plasticity mediates associative modifications of synaptic weights. Heterosynaptic plasticity counteracts runaway dynamics introduced by Hebbian-type rules and balances synaptic changes. It provides learning systems with stability and enhances synaptic competition. We conclude that homosynaptic and heterosynaptic plasticity represent complementary properties of modifiable synapses, and both are necessary for normal operation of neural systems with plastic synapses. PMID:24727248

  4. Human Maternal Brain Plasticity: Adaptation to Parenting

    ERIC Educational Resources Information Center

    Kim, Pilyoung

    2016-01-01

    New mothers undergo dynamic neural changes that support positive adaptation to parenting and the development of mother-infant relationships. In this article, I review important psychological adaptations that mothers experience during pregnancy and the early postpartum period. I then review evidence of structural and functional plasticity in human…

  5. Resveratrol: A Potential Hippocampal Plasticity Enhancer.

    PubMed

    Dias, Gisele Pereira; Cocks, Graham; do Nascimento Bevilaqua, Mário Cesar; Nardi, Antonio Egidio; Thuret, Sandrine

    2016-01-01

    The search for molecules capable of restoring altered hippocampal plasticity in psychiatric and neurological conditions is one of the most important tasks of modern neuroscience. It is well established that neural plasticity, such as the ability of the postnatal hippocampus to continuously generate newly functional neurons throughout life, a process called adult hippocampal neurogenesis (AHN), can be modulated not only by pharmacological agents, physical exercise, and environmental enrichment, but also by "nutraceutical" agents. In this review we focus on resveratrol, a phenol and phytoalexin found in the skin of grapes and red berries, as well as in nuts. Resveratrol has been reported to have antioxidant and antitumor properties, but its effects as a neural plasticity inducer are still debated. The current review examines recent evidence implicating resveratrol in regulating hippocampal neural plasticity and in mitigating the effects of various disorders and diseases on this important brain structure. Overall, findings show that resveratrol can improve cognition and mood and enhance hippocampal plasticity and AHN; however, some studies report opposite effects, with resveratrol inhibiting aspects of AHN. Therefore, further investigation is needed to resolve these controversies before resveratrol can be established as a safe coadjuvant in preventing and treating neuropsychiatric conditions. PMID:27313836

  6. Resveratrol: A Potential Hippocampal Plasticity Enhancer

    PubMed Central

    Dias, Gisele Pereira; Cocks, Graham; do Nascimento Bevilaqua, Mário Cesar; Nardi, Antonio Egidio

    2016-01-01

    The search for molecules capable of restoring altered hippocampal plasticity in psychiatric and neurological conditions is one of the most important tasks of modern neuroscience. It is well established that neural plasticity, such as the ability of the postnatal hippocampus to continuously generate newly functional neurons throughout life, a process called adult hippocampal neurogenesis (AHN), can be modulated not only by pharmacological agents, physical exercise, and environmental enrichment, but also by “nutraceutical” agents. In this review we focus on resveratrol, a phenol and phytoalexin found in the skin of grapes and red berries, as well as in nuts. Resveratrol has been reported to have antioxidant and antitumor properties, but its effects as a neural plasticity inducer are still debated. The current review examines recent evidence implicating resveratrol in regulating hippocampal neural plasticity and in mitigating the effects of various disorders and diseases on this important brain structure. Overall, findings show that resveratrol can improve cognition and mood and enhance hippocampal plasticity and AHN; however, some studies report opposite effects, with resveratrol inhibiting aspects of AHN. Therefore, further investigation is needed to resolve these controversies before resveratrol can be established as a safe coadjuvant in preventing and treating neuropsychiatric conditions. PMID:27313836

  7. Neuroimaging and plasticity in schizophrenia.

    PubMed

    Meyer-Lindenberg, Andreas; Tost, Heike

    2014-01-01

    Schizophrenia is a frequent and highly heritable brain disorder that typically manifests around or after puberty and has a fluctuating course. Multiple lines of evidence point to a neurodevelopmental origin of the illness and suggest that its (post) pubertal manifestation is related to genetic and environmental risk factors that interfere with the structural and functional reorganization of neural networks at this time. Longitudinal structural neuroimaging studies point to a progressive reduction in gray matter volume in many brain regions in schizophrenia. It has been proposed that these neuroimaging observations reflect an enduring disturbance of experience-dependent synaptic plasticity arising from developmental abnormalities in key neural circuits implicated in schizophrenia, including dorsolateral prefrontal cortex and hippocampal formation. Recent work has identified genetic variants linked to neural plasticity that are associated with changes in these circuits. Furthermore, non-invasive interventions such as transcranial magnetic stimulation have been shown to impact some of these systems-level intermediate phenotypes, suggesting a modifiability of these core pathophysiological processes of schizophrenia that may be exploited by therapy. PMID:23902983

  8. Neuroimaging and plasticity in schizophrenia.

    PubMed

    Meyer-Lindenberg, Andreas; Tost, Heike

    2014-01-01

    Schizophrenia is a frequent and highly heritable brain disorder that typically manifests around or after puberty and has a fluctuating course. Multiple lines of evidence point to a neurodevelopmental origin of the illness and suggest that its (post) pubertal manifestation is related to genetic and environmental risk factors that interfere with the structural and functional reorganization of neural networks at this time. Longitudinal structural neuroimaging studies point to a progressive reduction in gray matter volume in many brain regions in schizophrenia. It has been proposed that these neuroimaging observations reflect an enduring disturbance of experience-dependent synaptic plasticity arising from developmental abnormalities in key neural circuits implicated in schizophrenia, including dorsolateral prefrontal cortex and hippocampal formation. Recent work has identified genetic variants linked to neural plasticity that are associated with changes in these circuits. Furthermore, non-invasive interventions such as transcranial magnetic stimulation have been shown to impact some of these systems-level intermediate phenotypes, suggesting a modifiability of these core pathophysiological processes of schizophrenia that may be exploited by therapy.

  9. The plasticity of social emotions.

    PubMed

    Klimecki, Olga M

    2015-01-01

    Social emotions such as empathy or compassion greatly facilitate our interactions with others. Despite the importance of social emotions, scientific studies have only recently revealed functional neural plasticity associated with the training of such emotions. Using the framework of two antagonistic neural systems, the threat and social disconnection system on the one hand, and the reward and social connection system on the other, this article describes how training compassion and empathy can change the functioning of these systems in a targeted manner. Whereas excessive empathic sharing of suffering can increase negative feelings and activations in the insula and anterior cingulate cortex (corresponding to the threat and social disconnection system), compassion training can strengthen positive affect and neural activations in the medial orbitofrontal cortex and striatum (corresponding to the reward and social connection system). These neuroimaging findings are complemented by results from behavioral studies showing that compassion is linked to helping and forgiveness behavior, whereas empathic distress not only decreases helping behavior, but is even associated with increased aggressive behavior. Taken together, these data provide encouraging evidence for the plasticity of adaptive social emotions with wide-ranging implications for basic science and applied settings. PMID:26369728

  10. The plasticity of social emotions.

    PubMed

    Klimecki, Olga M

    2015-01-01

    Social emotions such as empathy or compassion greatly facilitate our interactions with others. Despite the importance of social emotions, scientific studies have only recently revealed functional neural plasticity associated with the training of such emotions. Using the framework of two antagonistic neural systems, the threat and social disconnection system on the one hand, and the reward and social connection system on the other, this article describes how training compassion and empathy can change the functioning of these systems in a targeted manner. Whereas excessive empathic sharing of suffering can increase negative feelings and activations in the insula and anterior cingulate cortex (corresponding to the threat and social disconnection system), compassion training can strengthen positive affect and neural activations in the medial orbitofrontal cortex and striatum (corresponding to the reward and social connection system). These neuroimaging findings are complemented by results from behavioral studies showing that compassion is linked to helping and forgiveness behavior, whereas empathic distress not only decreases helping behavior, but is even associated with increased aggressive behavior. Taken together, these data provide encouraging evidence for the plasticity of adaptive social emotions with wide-ranging implications for basic science and applied settings.

  11. Attentional Bias Associated with Habitual Self-Stigma in People with Mental Illness

    PubMed Central

    Chan, Kevin K. S.; Mak, Winnie W. S.

    2015-01-01

    As habitual self-stigma can have a tremendous negative impact on people with mental illness, it is of paramount importance to identify its risk factors. The present study aims to examine the potential contributory role of attentional bias in habitual self-stigma. People with mental illness having strong (n = 47) and weak (n = 47) habitual self-stigma completed a computerized emotional Stroop task which included stigma-related, positive, and non-affective words as stimuli. The strong habit group was found to exhibit faster color-naming of stigma-related words (compared to non-affective words), whereas the weak habit group showed no difference in the speed of response to different stimuli. These findings suggest that people with stronger habitual self-stigma may be more able to ignore the semantic meaning of stigma-related words and focus on the color-naming task. Moreover, people with stronger habitual self-stigma may have greater attentional avoidance of stigma-related material. The present study is the first to demonstrate a specific relationship between habitual self-stigma and biased processing of stigma-related information. In order to further determine the role and the nature of attentional bias in habitual self-stigma, future research should employ a broader range of experimental paradigms and measurement techniques to examine stigma-related attentional bias in people with mental illness. PMID:26177536

  12. Examining habituation of the startle reflex with the reinforcement sensitivity theory of personality.

    PubMed

    Blanch, Angel; Aluja, Anton; Blanco, Eduardo; Balada, Ferran

    2016-10-01

    The habituation of the acoustic startle reflex (ASR) was examined concerning individual differences in sensitivity to punishment (PUN) and sensitivity to reward (REW), within the general framework of the reinforcement sensitivity theory (RST) of personality. Two hypotheses derived from the RST were evaluated: the separable subsystems hypothesis and the joint subsystems hypothesis. In addition, we examined the direction of the relationship of PUN and REW with the habituation of the ASR. A habituation segment of electromyography recordings of the orbicularis oculi was assessed with an unconditional latent curve model. In accordance with the RST hypotheses, the relationship of PUN and REW on the habituation process was assessed with two conditional latent curve models. There was higher support for the separable subsystems hypothesis. In addition, PUN and REW related with the habituation trajectory of the ASR in the expected directions. Higher levels of PUN and lower levels of REW related with a slower habituation of the ASR, whereas lower levels of PUN and higher levels of REW related with a faster habituation of the ASR. PMID:27401960

  13. "My worries are rational, climate change is not": habitual ecological worrying is an adaptive response.

    PubMed

    Verplanken, Bas; Roy, Deborah

    2013-01-01

    Qualifications such as "global warming hysteria" and "energy policy schizophrenia" put forward by some climate change skeptics, usually outside the academic arena, may suggest that people who seriously worry about the environment suffer from psychological imbalance. The present study aimed to refute this thesis. While habitual worrying in general is strongly associated with psychopathological symptoms, in a survey a near-zero correlation was found between habitual ecological worrying and pathological worry. Instead, habitual ecological worrying was associated with pro-environmental attitudes and behaviors, and with a personality structure characterized by imagination and an appreciation for new ideas. The study had sufficient statistical power and measures were valid and reliable. The results confirm that those who habitually worry about the ecology are not only lacking in any psychopathology, but demonstrate a constructive and adaptive response to a serious problem. In the public domain, these findings may contribute to a more rational and less emotional debate on climate change and to the prevention of stigmatization of people who are genuinely concerned about our habitat and are prepared to do something about it ("habitual worriers are not crazy"). In the academic arena this study may contribute to environmental psychology ("habitual worrying is part of a green identity"), as well as to the literature on worry and anxiety ("habitual worrying can be a constructive response"). PMID:24023958

  14. Attentional Bias Associated with Habitual Self-Stigma in People with Mental Illness.

    PubMed

    Chan, Kevin K S; Mak, Winnie W S

    2015-01-01

    As habitual self-stigma can have a tremendous negative impact on people with mental illness, it is of paramount importance to identify its risk factors. The present study aims to examine the potential contributory role of attentional bias in habitual self-stigma. People with mental illness having strong (n = 47) and weak (n = 47) habitual self-stigma completed a computerized emotional Stroop task which included stigma-related, positive, and non-affective words as stimuli. The strong habit group was found to exhibit faster color-naming of stigma-related words (compared to non-affective words), whereas the weak habit group showed no difference in the speed of response to different stimuli. These findings suggest that people with stronger habitual self-stigma may be more able to ignore the semantic meaning of stigma-related words and focus on the color-naming task. Moreover, people with stronger habitual self-stigma may have greater attentional avoidance of stigma-related material. The present study is the first to demonstrate a specific relationship between habitual self-stigma and biased processing of stigma-related information. In order to further determine the role and the nature of attentional bias in habitual self-stigma, future research should employ a broader range of experimental paradigms and measurement techniques to examine stigma-related attentional bias in people with mental illness. PMID:26177536

  15. Examining habituation of the startle reflex with the reinforcement sensitivity theory of personality.

    PubMed

    Blanch, Angel; Aluja, Anton; Blanco, Eduardo; Balada, Ferran

    2016-10-01

    The habituation of the acoustic startle reflex (ASR) was examined concerning individual differences in sensitivity to punishment (PUN) and sensitivity to reward (REW), within the general framework of the reinforcement sensitivity theory (RST) of personality. Two hypotheses derived from the RST were evaluated: the separable subsystems hypothesis and the joint subsystems hypothesis. In addition, we examined the direction of the relationship of PUN and REW with the habituation of the ASR. A habituation segment of electromyography recordings of the orbicularis oculi was assessed with an unconditional latent curve model. In accordance with the RST hypotheses, the relationship of PUN and REW on the habituation process was assessed with two conditional latent curve models. There was higher support for the separable subsystems hypothesis. In addition, PUN and REW related with the habituation trajectory of the ASR in the expected directions. Higher levels of PUN and lower levels of REW related with a slower habituation of the ASR, whereas lower levels of PUN and higher levels of REW related with a faster habituation of the ASR.

  16. Social status-dependent modulation of LG-flip habituation in the crayfish.

    PubMed

    Araki, Makoto; Hasegawa, Takuya; Komatsuda, Shohei; Nagayama, Toshiki

    2013-02-15

    Strong stimuli applied to the tailfan of the crayfish Procambarus clarkii evoked lateral giant interneurone (LG)-mediated tailflips. When the sensory stimulus was applied repeatedly, the response of the LG habituated until it failed to give rise to a spike. We found that this LG-flip habituation was dependent on social status. With a short interstimulus interval of 5 s, the rate of habituation of the LG in both socially dominant and subordinate crayfish was lower than that in socially isolated animals. By contrast, with a long interstimulus interval of 60 s, the rate of habituation of subordinate animals was lower than that of both socially isolated and dominant animals. The excitability of the LGs following habituation was also dependent on social status. Following habituation, the spike response of LGs recovered within several minutes; however, they showed significant depression with a decrease in excitability. With a 5 or 60 s interstimulus interval, subordinate animals showed longer delays of depression compared with dominant animals. A decrease in the rate of habituation and a delay of depression in subordinate crayfish would be advantageous for maintaining an active escape response to evade repeated attacks of dominant animals and a reduced learning ability to adapt to social status.

  17. Attentional Bias Associated with Habitual Self-Stigma in People with Mental Illness.

    PubMed

    Chan, Kevin K S; Mak, Winnie W S

    2015-01-01

    As habitual self-stigma can have a tremendous negative impact on people with mental illness, it is of paramount importance to identify its risk factors. The present study aims to examine the potential contributory role of attentional bias in habitual self-stigma. People with mental illness having strong (n = 47) and weak (n = 47) habitual self-stigma completed a computerized emotional Stroop task which included stigma-related, positive, and non-affective words as stimuli. The strong habit group was found to exhibit faster color-naming of stigma-related words (compared to non-affective words), whereas the weak habit group showed no difference in the speed of response to different stimuli. These findings suggest that people with stronger habitual self-stigma may be more able to ignore the semantic meaning of stigma-related words and focus on the color-naming task. Moreover, people with stronger habitual self-stigma may have greater attentional avoidance of stigma-related material. The present study is the first to demonstrate a specific relationship between habitual self-stigma and biased processing of stigma-related information. In order to further determine the role and the nature of attentional bias in habitual self-stigma, future research should employ a broader range of experimental paradigms and measurement techniques to examine stigma-related attentional bias in people with mental illness.

  18. The Effect of Habitual Smoking on VO2max

    NASA Technical Reports Server (NTRS)

    Wier, Larry T.; Suminski, Richard R.; Poston, Walker S.; Randles, Anthony M.; Arenare, Brian; Jackson, Andrew S.

    2008-01-01

    VO2max is associated with many factors, including age, gender, physical activity, and body composition. It is popularly believed that habitual smoking lowers aerobic fitness. PURPOSE: to determine the effect of habitual smoking on VO2max after controlling for age, gender, activity and BMI. METHODS: 2374 men and 375 women employed at the NASA/Johnson Space Center were measured for VO2max by indirect calorimetry (RER>=1.1), activity by the 11 point (0-10) NASA Physical Activity Status Scale (PASS), BMI and smoking pack-yrs (packs day*y of smoking). Age was recorded in years and gender was coded as M=1, W=0. Pack.y was made a categorical variable consisting of four levels as follows: Never Smoked (0), Light (1-10), Regular (11-20), Heavy (>20). Group differences were verified by ANOVA. A General Linear Models (GLM) was used to develop two models to examine the relationship of smoking behavior on VO2max. GLM #1(without smoking) determined the combined effects of age, gender, PASS and BMI on VO2max. GLM #2 (with smoking) determined the added effects of smoking (pack.y groupings) on VO2max after controlling for age, gender, PASS and BMI. Constant errors (CE) were calculated to compare the accuracy of the two models for estimating the VO2max of the smoking subgroups. RESULTS: ANOVA affirmed the mean VO2max of each pack.y grouping decreased significantly (p<0.01) as the level of smoking exposure increased. GLM #1 showed that age, gender, PASS and BMI were independently related with VO2max (R2 = 0.642, SEE = 4.90, p<0.001). The added pack.y variables in GLM #2 were statistically significant (R2 change = 0.7%, p<0.01). Post hoc analysis showed that compared to Never Smoked, the effects on VO2max from Light and Regular smoking habits were -0.83 and -0.85 ml.kg- 1.min-1 respectively (p<0.05). The effect of Heavy smoking on VO2max was -2.56 ml.kg- 1.min-1 (p<0.001). The CE s of each smoking group in GLM #2 was smaller than the CE s of the smoking group counterparts in GLM #1

  19. Alarm pheromone habituation in Myzus persicae has fitness consequences and causes extensive gene expression changes.

    PubMed

    de Vos, Martin; Cheng, Wing Yin; Summers, Holly E; Raguso, Robert A; Jander, Georg

    2010-08-17

    In most aphid species, facultative parthenogenetic reproduction allows rapid growth and formation of large single-genotype colonies. Upon predator attack, individual aphids emit an alarm pheromone to warn the colony of this danger. (E)-beta-farnesene (EBF) is the predominant constituent of the alarm pheromone in Myzus persicae (green peach aphid) and many other aphid species. Continuous exposure to alarm pheromone in aphid colonies raised on transgenic Arabidopsis thaliana plants that produce EBF leads to habituation within three generations. Whereas naive aphids are repelled by EBF, habituated aphids show no avoidance response. Similarly, individual aphids from the habituated colony can revert back to being EBF-sensitive in three generations, indicating that this behavioral change is not caused by a genetic mutation. Instead, DNA microarray experiments comparing gene expression in naive and habituated aphids treated with EBF demonstrate an almost complete desensitization in the transcriptional response to EBF. Furthermore, EBF-habituated aphids show increased progeny production relative to EBF-responsive aphids, with or without EBF treatment. Although both naive and habituated aphids emit EBF upon damage, EBF-responsive aphids have a higher survival rate in the presence of a coccinellid predator (Hippodamia convergens), and thus outperform habituated aphids that do not show an avoidance response. These results provide evidence that aphid perception of conspecific alarm pheromone aids in predator avoidance and thereby bestows fitness benefits in survivorship and fecundity. Therefore, although habituated M. persicae produce more progeny, EBF-emitting transgenic plants may have practical applications in agriculture as a result of increased predation of habituated aphids. PMID:20679203

  20. Repeated cocaine exposure facilitates the expression of incentive motivation and induces habitual control in rats.

    PubMed

    LeBlanc, Kimberly H; Maidment, Nigel T; Ostlund, Sean B

    2013-01-01

    There is growing evidence that mere exposure to drugs can induce long-term alterations in the neural systems that mediate reward processing, motivation, and behavioral control, potentially causing the pathological pursuit of drugs that characterizes the addicted state. The incentive sensitization theory proposes that drug exposure potentiates the influence of reward-paired cues on behavior. It has also been suggested that drug exposure biases action selection towards the automatic execution of habits and away from more deliberate goal-directed control. The current study investigated whether rats given repeated exposure to peripherally administered cocaine would show alterations in incentive motivation (assayed using the Pavlovian-to-instrumental transfer (PIT) paradigm) or habit formation (assayed using sensitivity to reward devaluation). After instrumental and Pavlovian training for food pellet rewards, rats were given 6 daily injections of cocaine (15 mg/kg, IP) or saline, followed by a 10-d period of rest. Consistent with the incentive sensitization theory, cocaine-treated rats showed stronger cue-evoked lever pressing than saline-treated rats during the PIT test. The same rats were then trained on a new instrumental action with a new food pellet reward before undergoing a reward devaluation testing. Although saline-treated rats exhibited sensitivity to reward devaluation, indicative of goal-directed performance, cocaine-treated rats were insensitive to this treatment, suggesting a reliance on habitual processes. These findings, when taken together, indicate that repeated exposure to cocaine can cause broad alterations in behavioral control, spanning both motivational and action selection processes, and could therefore help explain aberrations of decision-making that underlie drug addiction. PMID:23646106

  1. Repeated cocaine exposure facilitates the expression of incentive motivation and induces habitual control in rats.

    PubMed

    LeBlanc, Kimberly H; Maidment, Nigel T; Ostlund, Sean B

    2013-01-01

    There is growing evidence that mere exposure to drugs can induce long-term alterations in the neural systems that mediate reward processing, motivation, and behavioral control, potentially causing the pathological pursuit of drugs that characterizes the addicted state. The incentive sensitization theory proposes that drug exposure potentiates the influence of reward-paired cues on behavior. It has also been suggested that drug exposure biases action selection towards the automatic execution of habits and away from more deliberate goal-directed control. The current study investigated whether rats given repeated exposure to peripherally administered cocaine would show alterations in incentive motivation (assayed using the Pavlovian-to-instrumental transfer (PIT) paradigm) or habit formation (assayed using sensitivity to reward devaluation). After instrumental and Pavlovian training for food pellet rewards, rats were given 6 daily injections of cocaine (15 mg/kg, IP) or saline, followed by a 10-d period of rest. Consistent with the incentive sensitization theory, cocaine-treated rats showed stronger cue-evoked lever pressing than saline-treated rats during the PIT test. The same rats were then trained on a new instrumental action with a new food pellet reward before undergoing a reward devaluation testing. Although saline-treated rats exhibited sensitivity to reward devaluation, indicative of goal-directed performance, cocaine-treated rats were insensitive to this treatment, suggesting a reliance on habitual processes. These findings, when taken together, indicate that repeated exposure to cocaine can cause broad alterations in behavioral control, spanning both motivational and action selection processes, and could therefore help explain aberrations of decision-making that underlie drug addiction.

  2. Cerebral blood flow and behavioural effects of caffeine in habitual and non-habitual consumers of caffeine: a near infrared spectroscopy study.

    PubMed

    Kennedy, David O; Haskell, Crystal F

    2011-03-01

    Caffeine has been shown to modulate cerebral blood flow, with little evidence of tolerance to these effects following habitual use. However, previous studies have focused on caffeine levels much higher than those found in dietary servings and have compared high caffeine consumers with low consumers rather than 'non-consumers'. The current placebo-controlled double-blind, balanced-crossover study employed near infrared spectroscopy to monitor pre-frontal cerebral-haemodynamics at rest and during completion of tasks that activate the pre-frontal cortex. Twenty healthy young habitual and non-habitual consumers of caffeine received 75 mg caffeine or placebo. Caffeine significantly decreased cerebral blood flow but this was subject to a significant interaction with consumption status, with no significant effect being shown in habitual consumers and an exaggerated effect in non-habitual consumers. These findings suggest that caffeine, at levels typically found in a single dietary serving, is able to modulate cerebral blood flow but these effects are subject to tolerance.

  3. Habitual alcohol seeking: modeling the transition from casual drinking to addiction.

    PubMed

    Barker, Jacqueline M; Taylor, Jane R

    2014-11-01

    The transition from goal-directed actions to habitual ethanol seeking models the development of addictive behavior that characterizes alcohol use disorders. The progression to habitual ethanol-seeking behavior occurs more rapidly than for natural rewards, suggesting that ethanol may act on habit circuit to drive the loss of behavioral flexibility. This review will highlight recent research that has focused on the formation and expression of habitual ethanol seeking, and the commonalities and distinctions between ethanol and natural reward-seeking habits, with the goal of highlighting important, understudied research areas that we believe will lead toward the development of novel treatment and prevention strategies for uncontrolled drinking.

  4. Habitual reading biases in the allocation of study time.

    PubMed

    Ariel, Robert; Al-Harthy, Ibrahim S; Was, Christopher A; Dunlosky, John

    2011-10-01

    Item order can bias learners' study decisions and undermine the use of more effective allocation strategies, such as allocating study time to items in one's region of proximal learning. In two experiments, we evaluated whether the influence of item order on study decisions reflects habitual responding based on a reading bias. We manipulated the order in which relatively easy, moderately difficult, and difficult items were presented from left to right on a computer screen and examined selection preference as a function of item order and item difficulty. Experiment 1a was conducted with native Arabic readers and in Arabic, and Experiment 1b was conducted with native English readers and in English. Students from both cultures prioritized items for study in the reading order of their native language: Arabic readers selected items for study in a right-to-left fashion, whereas English readers largely selected items from left to right. In Experiment 2, native English readers completed the same task as participants in Experiment 1b, but for some participants, lines of text were rotated upside down to encourage them to read from right to left. Participants who read upside-down text were more likely to first select items on the right side of an array than were participants who studied right-side-up text. These results indicate that reading habits can bias learners' study decisions and can undermine agenda-based regulation.

  5. Betting on Illusory Patterns: Probability Matching in Habitual Gamblers.

    PubMed

    Gaissmaier, Wolfgang; Wilke, Andreas; Scheibehenne, Benjamin; McCanney, Paige; Barrett, H Clark

    2016-03-01

    Why do people gamble? A large body of research suggests that cognitive distortions play an important role in pathological gambling. Many of these distortions are specific cases of a more general misperception of randomness, specifically of an illusory perception of patterns in random sequences. In this article, we provide further evidence for the assumption that gamblers are particularly prone to perceiving illusory patterns. In particular, we compared habitual gamblers to a matched sample of community members with regard to how much they exhibit the choice anomaly 'probability matching'. Probability matching describes the tendency to match response proportions to outcome probabilities when predicting binary outcomes. It leads to a lower expected accuracy than the maximizing strategy of predicting the most likely event on each trial. Previous research has shown that an illusory perception of patterns in random sequences fuels probability matching. So does impulsivity, which is also reported to be higher in gamblers. We therefore hypothesized that gamblers will exhibit more probability matching than non-gamblers, which was confirmed in a controlled laboratory experiment. Additionally, gamblers scored much lower than community members on the cognitive reflection task, which indicates higher impulsivity. This difference could account for the difference in probability matching between the samples. These results suggest that gamblers are more willing to bet impulsively on perceived illusory patterns.

  6. Blood groups and histocompatibility antigens in habitual abortion.

    PubMed

    Carapella-de Luca, E; Purpura, M; Coghi, I; Nicotra, M; Bottini, E

    1980-01-01

    Forty-six couples with at least two consecutive abortions were examined. The morphological and the functional clinical check-ups were constantly negative. In all the couples a karyotype analysis was carried out including an investigation of C and/or G bands. The phenotypes of ABO, Rh, MNSs and HLA-systems were also determined. No significant difference was observed in the distribution of ABO phenotypes between males and females, or between subjects with abortions and controls. Regarding the Rh system, the most important findings are the absence of phenotypes with the E allele in double dose, the reduction of the frequency of the CCDee phenotype and the increase in the frequency of the ccDEe phenotype. Concerning MNSs system, an increase in the frequency of the phenotypes with the S allele in double dose is observed. Females with habitual abortions show a higher incidence of Bw35 as compared both to males and to the controls. No significant differences were observed for other antigens. The persistence of a genetic disequilibrium both in the Rh and the MNSs systems suggests that the selection might act against certain antigenic combinations, independently from the state of materno-foetal compatibility. Though preliminary, our data seem to give some support to this hypothesis. They also suggest that Bw35 antigen may be important in human reproduction.

  7. Acute response to barefoot running in habitually shod males.

    PubMed

    Fleming, N; Walters, J; Grounds, J; Fife, L; Finch, A

    2015-08-01

    The aim of this study was to examine the immediate effects of barefoot (BF) running on lower limb kinematics and muscle activity in a group of habitually shod runners. Ten male runners with no prior BF or minimalist running experience performed 1-min bouts of treadmill running at 3 velocities in both shod and BF conditions. 2D video data were recorded in order to quantify ankle, knee and hip kinematics. Synchronous kinetic data were recorded from a force plate supporting the treadmill in order to quantify spatiotemporal variables. EMG data were collected from 6 lower limb muscles, quantifying recruitment patterns during discrete phases of the gait cycle. BF running resulted in significantly higher stride frequency and shorter ground contact times (P < .001). Additionally, BF running significantly reduced knee and hip range of motion but increased ankle range of motion during the absorptive phase of the stance. Alterations in ankle kinematics during BF running resulted from increased pre-activation of the medial (P < .05) and lateral (P < .01) gastrocnemius in addition to reductions in pre-activation of the tibialis anterior (P < .05). The results highlight that recruitment patterns and kinematics can change in as little as 30-s of BF running in individuals with no previous BF running experience.

  8. Effects of Habitual Anger on Employees’ Behavior during Organizational Change

    PubMed Central

    Bönigk, Mareike; Steffgen, Georges

    2013-01-01

    Organizational change is a particularly emotional event for those being confronted with it. Anger is a frequently experienced emotion under these conditions. This study analyses the influence of employees’ habitual anger reactions on their reported behavior during organizational change. It was explored whether anger reactions conducive to recovering or increasing individual well-being will enhance the likelihood of functional change behavior. Dysfunctional regulation strategies in terms of individual well-being are expected to decrease the likelihood of functional change behavior—mediated by the commitment to change. Four hundred and twelve employees of different organizations in Luxembourg undergoing organizational change participated in the study. Findings indicate that the anger regulation strategy venting, and humor increase the likelihood of deviant resistance to change. Downplaying the incident’s negative impact and feedback increase the likelihood of active support for change. The mediating effect of commitment to change has been found for humor and submission. The empirical findings suggest that a differentiated conceptualization of resistance to change is required. Specific implications for practical change management and for future research are discussed. PMID:24287849

  9. Habitual coffee consumption and blood pressure: An epidemiological perspective

    PubMed Central

    Geleijnse, Johanna M

    2008-01-01

    This paper summarizes the current epidemiological evidence on coffee consumption in relation to blood pressure (BP) and risk of hypertension. Data from cross-sectional studies suggest an inverse linear or U-shaped association of habitual coffee use with BP in different populations. Prospective studies suggest a protective effect of high coffee intake (4 or more cups per day) against hypertension, mainly in women. Furthermore, the risk of hypertension may be lower in coffee abstainers. Randomized controlled trials, which are mostly of short duration (1–12 weeks), have shown that coffee intake around 5 cups per day causes a small elevation in BP (∼2/1 mmHg) when compared to abstinence or use of decaffeinated coffee. With regard to underlying biological mechanisms, most research has been devoted to BP-raising effects of caffeine. However, there are many other substances in coffee, such as polyphenols, soluble fibre and potassium, which could exert a beneficial effect in the cardiovascular system. Although the precise nature of the relation between coffee and BP is still unclear, most evidence suggests that regular intake of caffeinated coffee does not increase the risk of hypertension. PMID:19183744

  10. Effects of habitual anger on employees' behavior during organizational change.

    PubMed

    Bönigk, Mareike; Steffgen, Georges

    2013-12-01

    Organizational change is a particularly emotional event for those being confronted with it. Anger is a frequently experienced emotion under these conditions. This study analyses the influence of employees' habitual anger reactions on their reported behavior during organizational change. It was explored whether anger reactions conducive to recovering or increasing individual well-being will enhance the likelihood of functional change behavior. Dysfunctional regulation strategies in terms of individual well-being are expected to decrease the likelihood of functional change behavior-mediated by the commitment to change. Four hundred and twelve employees of different organizations in Luxembourg undergoing organizational change participated in the study. Findings indicate that the anger regulation strategy venting, and humor increase the likelihood of deviant resistance to change. Downplaying the incident's negative impact and feedback increase the likelihood of active support for change. The mediating effect of commitment to change has been found for humor and submission. The empirical findings suggest that a differentiated conceptualization of resistance to change is required. Specific implications for practical change management and for future research are discussed. PMID:24287849

  11. Fatty acid composition of habitual omnivore and vegetarian diets.

    PubMed

    Mann, Neil; Pirotta, Yvonne; O'Connell, Stella; Li, Duo; Kelly, Fiona; Sinclair, Andy

    2006-07-01

    High-fat diets are implicated in the onset of cardiovascular disease (CVD), cancer, and obesity. Large intakes of saturated and trans FA, together with low levels of PUFA, particularly long-chain (LC) omega-3 (n-3) PUFA, appear to have the greatest impact on the development of CVD. A high n-6:n-3 PUFA ratio is also considered a marker of elevated risk of CVD, though little accurate data on dietary intake is available. A new Australian food composition database that reports FA in foods to two decimal places was used to assess intakes of FA in four habitual dietary groups. Analysis using the database found correlations between the dietary intakes of LC n-3 PUFA and the plasma phospholipid LC n-3 PUFA concentrations of omnivore and vegetarian subjects. High meat-eaters (HME), who consumed large amounts of food generally, had significantly higher LC n-3 PUFA intakes (0.29 g/d) than moderate meat-eaters (MME) (0.14 g/d), whose intakes in turn were significantly higher than those of ovolacto-vegetarians or vegans (both 0.01 g/d). The saturated FA intake of MME subjects (typical of adult male Australians) was not different from ovolacto-vegetarian intakes, whereas n-6:n-3 intake ratios in vegetarians were significantly higher than in omnivores. Thus, accurate dietary and plasma FA analyses suggest that regular moderate consumption of meat and fish maintains a plasma FA profile possibly more conducive to good health.

  12. Suppression to visual, auditory and gustatory stimuli habituates normally in rats with excitotoxic lesions of the perirhinal cortex

    PubMed Central

    Robinson, Jasper; Sanderson, David J.; Aggleton, John P.; Jenkins, Trisha A.

    2014-01-01

    In 3 habituation experiments, rats with excitotoxic lesions of the perirhinal cortex were found to be indistinguishable from control rats. Two of the habituation experiments examined the habituation of suppression of responding on an appetitive, instrumental baseline. One of those experiments used stimuli selected from the visual modality (lights), the other used auditory stimuli. The third experiment examined habituation of suppression of novel-flavored water consumption. In contrast to the null results on the habituation experiments, the perirhinal lesions disrupted transfer performance on a configural, visual discrimination, indicating the behavioral effectiveness of the lesions. Implications for comparator theories of habituation are considered and we conclude that others’ demonstrations of the sensitivity of object recognition to perirhinal cortex damage is not the result of standard habituation. PMID:20001107

  13. Acute effects of caffeine on heart rate variability in habitual caffeine consumers.

    PubMed

    Rauh, Robert; Burkert, Michaela; Siepmann, Martin; Mueck-Weymann, Michael

    2006-05-01

    During the last years, heart rate variability (HRV) has become a promising risk factor for cardiovascular events. However, the effect of caffeine on HRV in habitual caffeine consumers has barely been investigated. Therefore, we treated 30 male habitual caffeine users in a randomized double-blinded crossover study design with either placebo, 100 or 200 mg caffeine orally and determined parameters of HRV under resting conditions and metronomic breathing. As result, we could not detect significant differences in HRV parameters up to 90 min after drug ingestion. We conclude that modest amounts of caffeine do not reveal negative nor positive effects on HRV within the first 90 min after drug ingestion in young and healthy habitual caffeine consumers. However, further research is necessary to determine the effects of caffeine on HRV in habitual caffeine users, healthy as well as suffering from diabetes, hypertension and postmyocardial infarction.

  14. Effect of habituation on the susceptibility of the rat to restraint ulcers

    NASA Technical Reports Server (NTRS)

    Martin, M. S.; Martin, F.; Lambert, R.

    1980-01-01

    The frequency and gravity of restraint ulcers were found to significantly diminish in rats previously exposed to brief periods of immobilization. The rats' becoming habituated to restraint conditions probably explains this phenomenon.

  15. Habituation of single CO2 laser-evoked responses during interictal phase of migraine.

    PubMed

    de Tommaso, Marina; Libro, Giuseppe; Guido, Marco; Losito, Luciana; Lamberti, Paolo; Livrea, Paolo

    2005-09-01

    A reduced habituation of averaged laser-evoked potential (LEP) amplitudes was previously found in migraine patients. The aim of the present study was to assess the habituation of single LEP responses and pain sensation during the interictal phase in migraine patients. Fourteen migraine patients were compared with ten control subjects. The pain stimulus was laser pulses, generated by CO2 laser, delivered to right supraorbital zone. Patients were evaluated during attack-free conditions. The LEP habituation was studied by measuring the changes of LEP amplitudes across and within three consecutive repetitions of 21 non-averaged trials. In migraine patients the N2-P2 wave amplitudes did not show a tendency toward habituation across and, above all, within the three repetitions. Anomalous behaviour of nociceptive cortex during the interictal phase of migraine may predispose patients to headache occurrence and persistence. PMID:16362662

  16. Habituation of single CO2 laser-evoked responses during interictal phase of migraine.

    PubMed

    de Tommaso, Marina; Libro, Giuseppe; Guido, Marco; Losito, Luciana; Lamberti, Paolo; Livrea, Paolo

    2005-09-01

    A reduced habituation of averaged laser-evoked potential (LEP) amplitudes was previously found in migraine patients. The aim of the present study was to assess the habituation of single LEP responses and pain sensation during the interictal phase in migraine patients. Fourteen migraine patients were compared with ten control subjects. The pain stimulus was laser pulses, generated by CO2 laser, delivered to right supraorbital zone. Patients were evaluated during attack-free conditions. The LEP habituation was studied by measuring the changes of LEP amplitudes across and within three consecutive repetitions of 21 non-averaged trials. In migraine patients the N2-P2 wave amplitudes did not show a tendency toward habituation across and, above all, within the three repetitions. Anomalous behaviour of nociceptive cortex during the interictal phase of migraine may predispose patients to headache occurrence and persistence.

  17. Habituation in goldfish (Carassius auratus) is impaired by increased interstimulus interval, interval variability, and telencephalic ablation.

    PubMed

    Laming, P R; McKinney, S J

    1990-12-01

    Goldfish (Carassius auratus) were fitted with electrodes and buccal catheters for monitoring electrocardiograms and ventilations, respectively. A 2-s "light-on" stimulus was repeatedly presented to groups of fish at fixed interstimulus intervals (ISIs) of 1 or 2 min or at variable ISIs with a mean duration of 1 or 2 min. Normal fish, fish with telencephalic ablation, and fish with sham operations were compared for responsiveness and habituation to repeatedly presented stimuli. The longer the ISI, the greater the number of stimuli that were required for habituation. Increased ISI variability also decreased the rate of habituation. Furthermore, fish with telencephalic ablation had significantly slower habituation rates with both fixed and variable ISI schedules.

  18. In vivo Ca2+ imaging reveals that decreased dendritic excitability drives startle habituation

    PubMed Central

    Marsden, Kurt C.; Granato, Michael

    2015-01-01

    Summary Exposure to repetitive startling stimuli induces habitation, a simple form of learning. Despite its simplicity, the precise cellular mechanisms by which repeated stimulation converts a robust behavioral response to behavioral indifference are unclear. Here, we use head-restrained zebrafish larvae to monitor subcellular Ca2+ dynamics in Mauthner neurons, the startle command neurons, during startle habituation in vivo. Using the Ca2+ reporter GCaMP6s we find that the amplitude of Ca2+ signals in the lateral dendrite of the Mauthner neuron determines startle probability and that depression of this dendritic activity rather than downstream inhibition mediates short-term habituation mediates glycine and N-methyl-D-aspartate (NMDA) receptor dependent short-term habituation. Combined, our results suggest a model for habituation learning in which increased inhibitory drive from feedforward inhibitory neurons combined with decreased excitatory input from auditory afferents decreases dendritic and Mauthner neuron excitability. PMID:26655893

  19. Motivational variables and the sensitization and habituation of aggression in the convict cichlid (Cichlasoma nigrofasciatum).

    PubMed

    Peeke, H V; Avis, H H; Peeke, S C

    1979-12-01

    Four experiments using territorial Convict Cichlids investigated motivational factors involved in the incremental and decremental processes associated with aggression resulting from exposure to conspecifics intruded into the territory. The first three experiments varied some single aspect of the experimental situation (temperature, distance from the nest or size of the intruder). The fourth experiment combined those factors which resulted in faster habituation (small intruder, far from the nest, in cool water) and compared the response to factors which resulted in slower habituation or an increase in response rate (large intruder, close to the nest in warm water). While a combination of higher intensity stimuli did result in slower habituation than the combination of lower intensity stimuli, response rate was not a simple algebraic summation of the factors. Results are discussed in relation to multi-factor theory of habituation and the nature of "drive".

  20. Cortical Plasticity, Excitatory–Inhibitory Balance, and Sensory Perception

    PubMed Central

    Carcea, Ioana; Froemke, Robert C.

    2015-01-01

    Experience shapes the central nervous system throughout life. Structural and functional plasticity confers a remarkable ability on the brain, allowing neural circuits to adequately adapt to dynamic environments. This process can require selective adjustment of many excitatory and inhibitory synapses in an organized manner, in such a way as to enhance representations of behaviorally important sensory stimuli while preserving overall network excitability. The rules and mechanisms that orchestrated these changes across different synapses and throughout neuronal ensembles are beginning to be understood. Here, we review the evidence connecting synaptic plasticity to functional plasticity and perceptual learning, focusing on the roles of various neuromodulatory systems in enabling plasticity of adult neural circuits. However, the challenge remains to appropriately leverage these systems and forms of plasticity to persistently improve perceptual abilities and behavioral performance. PMID:24309251

  1. Habituation and adaptation of the vestibuloocular reflex: a model of differential control by the vestibulocerebellum

    NASA Technical Reports Server (NTRS)

    Cohen, H.; Cohen, B.; Raphan, T.; Waespe, W.

    1992-01-01

    We habituated the dominant time constant of the horizontal vestibuloocular reflex (VOR) of rhesus and cynomolgus monkeys by repeated testing with steps of velocity about a vertical axis and adapted the gain of the VOR by altering visual input with magnifying and reducing lenses. After baseline values were established, the nodulus and ventral uvula of the vestibulocerebellum were ablated in two monkeys, and the effects of nodulouvulectomy and flocculectomy on VOR gain adaptation and habituation were compared. The VOR time constant decreased with repeated testing, rapidly at first and more slowly thereafter. The gain of the VOR was unaffected. Massed trials were more effective than distributed trials in producing habituation. Regardless of the schedule of testing, the VOR time constant never fell below the time constant of the semicircular canals (approximately 5 s). This finding indicates that only the slow component of the vestibular response, the component produced by velocity storage, was habituated. In agreement with this, the time constant of optokinetic after-nystagmus (OKAN) was habituated concurrently with the VOR. Average values for VOR habituation were obtained on a per session basis for six animals. The VOR gain was adapted by natural head movements in partially habituated monkeys while they wore x 2.2 magnifying or x 0.5 reducing lenses. Adaptation occurred rapidly and reached about +/- 30%, similar to values obtained using forced rotation. VOR gain adaptation did not cause additional habituation of the time constant. When the VOR gain was reduced in animals with a long VOR time constant, there were overshoots in eye velocity that peaked at about 6-8 s after the onset or end of constant-velocity rotation. These overshoots occurred at times when the velocity storage integrator would have been maximally activated by semicircular canal input. Since the activity generated in the canals is not altered by visual adaptation, this finding indicates that the gain

  2. Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

    PubMed

    Valeriani, M; de Tommaso, M; Restuccia, D; Le Pera, D; Guido, M; Iannetti, G D; Libro, G; Truini, A; Di Trapani, G; Puca, F; Tonali, P; Cruccu, G

    2003-09-01

    The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in

  3. Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

    PubMed

    Valeriani, M; de Tommaso, M; Restuccia, D; Le Pera, D; Guido, M; Iannetti, G D; Libro, G; Truini, A; Di Trapani, G; Puca, F; Tonali, P; Cruccu, G

    2003-09-01

    The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in

  4. Music-induced cortical plasticity and lateral inhibition in the human auditory cortex as foundations for tonal tinnitus treatment

    PubMed Central

    Pantev, Christo; Okamoto, Hidehiko; Teismann, Henning

    2012-01-01

    Over the past 15 years, we have studied plasticity in the human auditory cortex by means of magnetoencephalography (MEG). Two main topics nurtured our curiosity: the effects of musical training on plasticity in the auditory system, and the effects of lateral inhibition. One of our plasticity studies found that listening to notched music for 3 h inhibited the neuronal activity in the auditory cortex that corresponded to the center-frequency of the notch, suggesting suppression of neural activity by lateral inhibition. Subsequent research on this topic found that suppression was notably dependent upon the notch width employed, that the lower notch-edge induced stronger attenuation of neural activity than the higher notch-edge, and that auditory focused attention strengthened the inhibitory networks. Crucially, the overall effects of lateral inhibition on human auditory cortical activity were stronger than the habituation effects. Based on these results we developed a novel treatment strategy for tonal tinnitus—tailor-made notched music training (TMNMT). By notching the music energy spectrum around the individual tinnitus frequency, we intended to attract lateral inhibition to auditory neurons involved in tinnitus perception. So far, the training strategy has been evaluated in two studies. The results of the initial long-term controlled study (12 months) supported the validity of the treatment concept: subjective tinnitus loudness and annoyance were significantly reduced after TMNMT but not when notching spared the tinnitus frequencies. Correspondingly, tinnitus-related auditory evoked fields (AEFs) were significantly reduced after training. The subsequent short-term (5 days) training study indicated that training was more effective in the case of tinnitus frequencies ≤ 8 kHz compared to tinnitus frequencies >8 kHz, and that training should be employed over a long-term in order to induce more persistent effects. Further development and evaluation of TMNMT therapy

  5. Neuromodulators, stress and plasticity: a role for endocannabinoid signalling.

    PubMed

    Senst, Laura; Bains, Jaideep

    2014-01-01

    Any unanticipated threat to survival triggers an immediate sequence of events in the brain that culminate in a coordinated neural, endocrine and behavioural response. There is increasing evidence that stress itself modifies neural circuits. In other words, neural stress circuits learn from stress. This self-teaching is surprising as one might expect these essential circuits to be hard-wired. Our recent findings, however, indicate that repeated homotypic stress in rats causes functional changes in neural circuitry in the hypothalamus. In particular, we focus on signalling via endocannabinoids and describe plasticity in this system that impacts fast retrograde signalling at synapses on to the stress command neurons in the brain. Interestingly, this plasticity appears to be limited to early adolescence, hinting at unique modes of control of neural circuits by stress during different developmental stages.

  6. Validity and Reproducibility of a Habitual Dietary Fibre Intake Short Food Frequency Questionnaire

    PubMed Central

    Healey, Genelle; Brough, Louise; Murphy, Rinki; Hedderley, Duncan; Butts, Chrissie; Coad, Jane

    2016-01-01

    Low dietary fibre intake has been associated with poorer health outcomes, therefore having the ability to be able to quickly assess an individual’s dietary fibre intake would prove useful in clinical practice and for research purposes. Current dietary assessment methods such as food records and food frequency questionnaires are time-consuming and burdensome, and there are presently no published short dietary fibre intake questionnaires that can quantify an individual’s total habitual dietary fibre intake and classify individuals as low, moderate or high habitual dietary fibre consumers. Therefore, we aimed to develop and validate a habitual dietary fibre intake short food frequency questionnaire (DFI-FFQ) which can quickly and accurately classify individuals based on their habitual dietary fibre intake. In this study the DFI-FFQ was validated against the Monash University comprehensive nutrition assessment questionnaire (CNAQ). Fifty-two healthy, normal weight male (n = 17) and female (n = 35) participants, aged between 21 and 61 years, completed the DFI-FFQ twice and the CNAQ once. All eligible participants completed the study, however the data from 46% of the participants were excluded from analysis secondary to misreporting. The DFI-FFQ cannot accurately quantify total habitual dietary fibre intakes, however, it is a quick, valid and reproducible tool in classifying individuals based on their habitual dietary fibre intakes. PMID:27626442

  7. Habituation of the cardiac response to involuntary diving in diving and dabbling ducks.

    PubMed

    Gabbott, G R; Jones, D R

    1987-09-01

    1. Bradycardia in response to forced submergence was habituated in dabbling (Anas platyrhynchos, Linnaeus) and diving (Aythya americana, Eyton) ducks by repetitively submerging the animals, each day for several days, for periods of 40 and 20 s, respectively. The onset of pronounced bradycardia was delayed with each successive trial, until little or no bradycardia occurred during submergence. Diving bradycardia is driven by chemoreceptors in the dabbler and caused by stimulation of narial receptors in the diver. 2. Mean arterial blood pressure in dives was unchanged from pre-dive levels in both naive and trained dabbling ducks. PaO2, PaCO2 and pHa at the end of a dive were similar before and after habituation training. 3. Bradycardia occurred in dives by habituated dabbling ducks if the animal breathed 15% O2 before submergence. The ventilatory responses to breathing high and low levels of oxygen were unaffected by habituation training. 4. The changes in blood gases during dives by naive and habituated dabbling ducks were the same: therefore, in the absence of a demonstrated decrement in receptor chemosensitivity or efferent potency, the locus of habituation must reside in the central nervous system. PMID:3694117

  8. A Transcriptome-Based Characterization of Habituation in Plant Tissue Culture1[W

    PubMed Central

    Pischke, Melissa S.; Huttlin, Edward L.; Hegeman, Adrian D.; Sussman, Michael R.

    2006-01-01

    For the last 50 years, scientists have recognized that varying ratios of the plant hormones cytokinin and auxin induce plant cells to form particular tissues: undifferentiated calli, shoot structures, root structures, or a whole plant. Proliferation of undifferentiated callus tissue, greening, and the formation of shoot structures are all cytokinin-dependent processes. Habituation refers to a naturally occurring phenomenon whereby callus cultures, upon continued passage, lose their requirement for cytokinin. Earlier studies of calli with a higher-than-normal cytokinin content indicate that overproduction of cytokinin by the culture tissues is a possible explanation for this acquired cytokinin independence. A transcriptome-based analysis of a well established habituated Arabidopsis (Arabidopsis thaliana) cell culture line was undertaken, to explore genome-wide expression changes underlying the phenomenon of habituation. Increased levels of expression of the cytokinin receptor CRE1, as well as altered levels of expression of several other genes involved in cytokinin signaling, indicated that naturally acquired deregulation of cytokinin-signaling components could play a previously unrecognized role in habituation. Up-regulation of several cytokinin oxidases, down-regulation of several known cytokinin-inducible genes, and a lack of regulation of the cytokinin synthases indicated that increases in hormone concentration may not be required for habituation. In addition, up-regulation of the homeodomain transcription factor FWA, transposon-related elements, and several DNA- and chromatin-modifying enzymes indicated that epigenetic changes contribute to the acquisition of cytokinin habituation. PMID:16489130

  9. Dynamic changes in reinforcer effectiveness: satiation and habituation have different implications for theory and practice.

    PubMed

    McSweeney, Frances K

    2004-01-01

    Reinforcers lose their effectiveness when they are presented repeatedly. Early researchers labeled this loss of effectiveness as satiation without conducting an experimental analysis. When such an analysis is conducted, habituation provides a more precise and empirically accurate label for the changes in reinforcer effectiveness. This paper reviews some of the data that suggest that habituation occurs to repeatedly presented reinforcers. It also argues that habituation has surprisingly different implications than satiation for theory and practice in behavior analysis. For example, postulating that habituation occurs to repeatedly presented reinforcers suggests ways for maintaining the strength of an existing reinforcer and for weakening the strength of a problematic reinforcer that differ from those implied by an account in terms of satiation. An habituation account may also lead to different ways of conceptualizing the regulation of behavior. For example, habituation may be a single-process contributor to the termination of behaviors that are usually attributed to satiation (e.g., ingestive behaviors such as eating and drinking), fatigue (e.g., energetic behaviors such as running), the waning of attention (e.g., cognitive behaviors such as studying), and pharmacodynamic factors (e.g., drug taking).

  10. Dynamic changes in reinforcer effectiveness: Satiation and habituation have different implications for theory and practice

    PubMed Central

    McSweeney, Frances K.

    2004-01-01

    Reinforcers lose their effectiveness when they are presented repeatedly. Early researchers labeled this loss of effectiveness as satiation without conducting an experimental analysis. When such an analysis is conducted, habituation provides a more precise and empirically accurate label for the changes in reinforcer effectiveness. This paper reviews some of the data that suggest that habituation occurs to repeatedly presented reinforcers. It also argues that habituation has surprisingly different implications than satiation for theory and practice in behavior analysis. For example, postulating that habituation occurs to repeatedly presented reinforcers suggests ways for maintaining the strength of an existing reinforcer and for weakening the strength of a problematic reinforcer that differ from those implied by an account in terms of satiation. An habituation account may also lead to different ways of conceptualizing the regulation of behavior. For example, habituation may be a single-process contributor to the termination of behaviors that are usually attributed to satiation (e.g., ingestive behaviors such as eating and drinking), fatigue (e.g., energetic behaviors such as running), the waning of attention (e.g., cognitive behaviors such as studying), and pharmacodynamic factors (e.g., drug taking). PMID:22478427

  11. Validity and Reproducibility of a Habitual Dietary Fibre Intake Short Food Frequency Questionnaire.

    PubMed

    Healey, Genelle; Brough, Louise; Murphy, Rinki; Hedderley, Duncan; Butts, Chrissie; Coad, Jane

    2016-01-01

    Low dietary fibre intake has been associated with poorer health outcomes, therefore having the ability to be able to quickly assess an individual's dietary fibre intake would prove useful in clinical practice and for research purposes. Current dietary assessment methods such as food records and food frequency questionnaires are time-consuming and burdensome, and there are presently no published short dietary fibre intake questionnaires that can quantify an individual's total habitual dietary fibre intake and classify individuals as low, moderate or high habitual dietary fibre consumers. Therefore, we aimed to develop and validate a habitual dietary fibre intake short food frequency questionnaire (DFI-FFQ) which can quickly and accurately classify individuals based on their habitual dietary fibre intake. In this study the DFI-FFQ was validated against the Monash University comprehensive nutrition assessment questionnaire (CNAQ). Fifty-two healthy, normal weight male (n = 17) and female (n = 35) participants, aged between 21 and 61 years, completed the DFI-FFQ twice and the CNAQ once. All eligible participants completed the study, however the data from 46% of the participants were excluded from analysis secondary to misreporting. The DFI-FFQ cannot accurately quantify total habitual dietary fibre intakes, however, it is a quick, valid and reproducible tool in classifying individuals based on their habitual dietary fibre intakes.

  12. Validity and Reproducibility of a Habitual Dietary Fibre Intake Short Food Frequency Questionnaire.

    PubMed

    Healey, Genelle; Brough, Louise; Murphy, Rinki; Hedderley, Duncan; Butts, Chrissie; Coad, Jane

    2016-01-01

    Low dietary fibre intake has been associated with poorer health outcomes, therefore having the ability to be able to quickly assess an individual's dietary fibre intake would prove useful in clinical practice and for research purposes. Current dietary assessment methods such as food records and food frequency questionnaires are time-consuming and burdensome, and there are presently no published short dietary fibre intake questionnaires that can quantify an individual's total habitual dietary fibre intake and classify individuals as low, moderate or high habitual dietary fibre consumers. Therefore, we aimed to develop and validate a habitual dietary fibre intake short food frequency questionnaire (DFI-FFQ) which can quickly and accurately classify individuals based on their habitual dietary fibre intake. In this study the DFI-FFQ was validated against the Monash University comprehensive nutrition assessment questionnaire (CNAQ). Fifty-two healthy, normal weight male (n = 17) and female (n = 35) participants, aged between 21 and 61 years, completed the DFI-FFQ twice and the CNAQ once. All eligible participants completed the study, however the data from 46% of the participants were excluded from analysis secondary to misreporting. The DFI-FFQ cannot accurately quantify total habitual dietary fibre intakes, however, it is a quick, valid and reproducible tool in classifying individuals based on their habitual dietary fibre intakes. PMID:27626442

  13. Interictal lack of habituation of mismatch negativity in migraine.

    PubMed

    de Tommaso, M; Guido, M; Libro, G; Losito, L; Difruscolo, O; Sardaro, M; Puca, F M

    2004-08-01

    The aim was to study mismatch negativity features and habituation during the interictal phase of migraine. In migraine patients, a strong negative correlation has been found between the initial amplitude of long latency auditory-evoked potentials and their amplitude increase during subsequent averaging. We studied 12 outpatients with a diagnosis of migraine without aura recorded in a headache-free interval and 10 gender- and age-matched healthy volunteers not suffering from any recurrent headache. The experiment consisted of two sequential blocks of 2000 stimulations, during which 1800 (90%) recordings for standard tones and 200 (10%) for target tones were selected for averaging. The latency of the N1 component was significantly increased in migraine patients in respect of controls in both the first and second repetitions; the MMN latency was increased in the second repetition. In the control group the MMN amplitude decreased on average by 3.2 +/- 1.4 microV in the second trial, whereas in migraine patients it showed a slight increase of 0.21 +/- 0.11 microV in the second repetition. The MMN latency relieved in the second trial was significantly correlated with the duration of illness in the migraine patients (Spearman correlation coefficient: 0.69; P < 0.05). The increases in N1 latency and MMN latency and amplitude, the latter correlated with duration of illness, seemed to be due to a reduced anticipatory effect of stimulus repetition in migraine patients. This suggests that such hypo-activity of automatic cortical processes, subtending the discrimination of acoustic stimuli, may be a basic abnormality in migraine, developing in the course of the disease. PMID:15265055

  14. Interictal lack of habituation of mismatch negativity in migraine.

    PubMed

    de Tommaso, M; Guido, M; Libro, G; Losito, L; Difruscolo, O; Sardaro, M; Puca, F M

    2004-08-01

    The aim was to study mismatch negativity features and habituation during the interictal phase of migraine. In migraine patients, a strong negative correlation has been found between the initial amplitude of long latency auditory-evoked potentials and their amplitude increase during subsequent averaging. We studied 12 outpatients with a diagnosis of migraine without aura recorded in a headache-free interval and 10 gender- and age-matched healthy volunteers not suffering from any recurrent headache. The experiment consisted of two sequential blocks of 2000 stimulations, during which 1800 (90%) recordings for standard tones and 200 (10%) for target tones were selected for averaging. The latency of the N1 component was significantly increased in migraine patients in respect of controls in both the first and second repetitions; the MMN latency was increased in the second repetition. In the control group the MMN amplitude decreased on average by 3.2 +/- 1.4 microV in the second trial, whereas in migraine patients it showed a slight increase of 0.21 +/- 0.11 microV in the second repetition. The MMN latency relieved in the second trial was significantly correlated with the duration of illness in the migraine patients (Spearman correlation coefficient: 0.69; P < 0.05). The increases in N1 latency and MMN latency and amplitude, the latter correlated with duration of illness, seemed to be due to a reduced anticipatory effect of stimulus repetition in migraine patients. This suggests that such hypo-activity of automatic cortical processes, subtending the discrimination of acoustic stimuli, may be a basic abnormality in migraine, developing in the course of the disease.

  15. Foot Morphological Difference between Habitually Shod and Unshod Runners

    PubMed Central

    Shu, Yang; Mei, Qichang; Fernandez, Justin; Li, Zhiyong; Feng, Neng; Gu, Yaodong

    2015-01-01

    Foot morphology and function has received increasing attention from both biomechanics researchers and footwear manufacturers. In this study, 168 habitually unshod runners (90 males whose age, weight & height were 23±2.4years, 66±7.1kg & 1.68±0.13m and 78 females whose age, weight & height were 22±1.8years, 55±4.7kg & 1.6±0.11m) (Indians) and 196 shod runners (130 males whose age, weight & height were 24±2.6years, 66±8.2kg & 1.72±0.18m and 66 females whose age, weight & height were 23±1.5years, 54±5.6kg & 1.62±0.15m)(Chinese) participated in a foot scanning test using the easy-foot-scan (a three-dimensional foot scanning system) to obtain 3D foot surface data and 2D footprint imaging. Foot length, foot width, hallux angle and minimal distance from hallux to second toe were calculated to analyze foot morphological differences. This study found that significant differences exist between groups (shod Chinese and unshod Indians) for foot length (female p = 0.001), width (female p = 0.001), hallux angle (male and female p = 0.001) and the minimal distance (male and female p = 0.001) from hallux to second toe. This study suggests that significant differences in morphology between different ethnicities could be considered for future investigation of locomotion biomechanics characteristics between ethnicities and inform last shape and design so as to reduce injury risks and poor performance from mal-fit shoes. PMID:26148059

  16. Brain plasticity and motor practice in cognitive aging

    PubMed Central

    Cai, Liuyang; Chan, John S. Y.; Yan, Jin H.; Peng, Kaiping

    2014-01-01

    For more than two decades, there have been extensive studies of experience-based neural plasticity exploring effective applications of brain plasticity for cognitive and motor development. Research suggests that human brains continuously undergo structural reorganization and functional changes in response to stimulations or training. From a developmental point of view, the assumption of lifespan brain plasticity has been extended to older adults in terms of the benefits of cognitive training and physical therapy. To summarize recent developments, first, we introduce the concept of neural plasticity from a developmental perspective. Secondly, we note that motor learning often refers to deliberate practice and the resulting performance enhancement and adaptability. We discuss the close interplay between neural plasticity, motor learning and cognitive aging. Thirdly, we review research on motor skill acquisition in older adults with, and without, impairments relative to aging-related cognitive decline. Finally, to enhance future research and application, we highlight the implications of neural plasticity in skills learning and cognitive rehabilitation for the aging population. PMID:24653695

  17. Human Maternal Brain Plasticity: Adaptation to Parenting.

    PubMed

    Kim, Pilyoung

    2016-09-01

    New mothers undergo dynamic neural changes that support positive adaptation to parenting and the development of mother-infant relationships. In this article, I review important psychological adaptations that mothers experience during pregnancy and the early postpartum period. I then review evidence of structural and functional plasticity in human mothers' brains, and explore how such plasticity supports mothers' psychological adaptation to parenting and sensitive maternal behaviors. Last, I discuss pregnancy and the early postpartum period as a window of vulnerabilities and opportunities when the human maternal brain is influenced by stress and psychopathology, but also receptive to interventions. PMID:27589497

  18. Self-objectification, habitual body monitoring, and body dissatisfaction in older European American women: exploring age and feminism as moderators.

    PubMed

    Grippo, Karen P; Hill, Melanie S

    2008-06-01

    This study examined the influence of feminist attitudes on self-objectification, habitual body monitoring, and body dissatisfaction in middle age and older women. The participants were 138 European American heterosexual women ranging in age from 40 to 87 years old. Consistent with previous research, self-objectification and habitual body monitoring were positively correlated with body dissatisfaction and, self-objectification and habitual body monitoring remained stable across the lifespan. While age did not moderate the relationship between self-objectification and body dissatisfaction, age was found to moderate the relationship between habitual body monitoring and body dissatisfaction such that the relationship was smaller for older women than for middle-aged women. Interestingly, feminist attitudes were not significantly correlated with body dissatisfaction, self-objectification, or habitual body monitoring, and endorsement of feminist attitudes was not found to moderate the relationship between self-objectification or habitual body monitoring and body dissatisfaction. Potential implications for older women are discussed.

  19. The Effects of Simulated Stuttering and Prolonged Speech on the Neural Activation Patterns of Stuttering and Nonstuttering Adults

    ERIC Educational Resources Information Center

    De Nil, Luc F.; Beal, Deryk S.; Lafaille, Sophie J.; Kroll, Robert M.; Crawley, Adrian P.; Gracco, Vincent L.

    2008-01-01

    Functional magnetic resonance imaging was used to investigate the neural correlates of passive listening, habitual speech and two modified speech patterns (simulated stuttering and prolonged speech) in stuttering and nonstuttering adults. Within-group comparisons revealed increased right hemisphere biased activation of speech-related regions…

  20. Interactions of time of day and sleep with between-session habituation and extinction memory in young adult males

    PubMed Central

    Pace-Schott, Edward F.; Tracy, Lauren E.; Rubin, Zoe; Mollica, Adrian G.; Ellenbogen, Jeffrey M.; Bianchi, Matt T.; Milad, Mohammed R.; Pitman, Roger K.; Orr, Scott P.

    2014-01-01

    Within-session habituation and extinction learning co-occur as do subsequent consolidation of habituation (i.e., between-session habituation) and extinction memory. We sought to determine if, as we predicted: (1) between-session habituation is greater across a night of sleep vs. a day awake; (2) time-of-day accounts for differences; (3) between-session habituation predicts consolidation of extinction memory; (4) sleep predicts between-session habituation and/or extinction memory. Participants (N=28) completed 4–5 sessions alternating between mornings and evenings over 3 successive days (2 nights) with session 1 in either the morning (N=13) or evening (N=15). Twelve participants underwent laboratory polysomnography. During 4 sessions, participants completed a loud-tone habituation protocol while skin-conductance response (SCR), blink-startle electromyography (EMG), heart-rate acceleration (HRA) and deceleration (HRD) were recorded. For sessions 1 and 2, between-session habituation of EMG, SCR and HRD was greater across sleep. SCR and HRD were generally lower in the morning. Between-session habituation of SCR for sessions 1 and 2 was positively related to intervening (first night) slow wave sleep. In the evening before night 2, participants also underwent fear conditioning and extinction learning phases of a second protocol. Extinction recall was tested the following morning. Extinction recall was predicted only by between-session habituation of SCR across the same night (second night) and by intervening REM. We conclude that: 1) sleep augments between-session habituation, as does morning testing; 2) extinction recall is predicted by concurrent between-session habituation; and 3) both phenomena may be influenced by sleep. PMID:24481663

  1. Conditional Knockout of Tumor Overexpressed Gene in Mouse Neurons Affects RNA Granule Assembly, Granule Translation, LTP and Short Term Habituation

    PubMed Central

    Barbarese, Elisa; Ifrim, Marius F.; Hsieh, Lawrence; Guo, Caiying; Tatavarty, Vedakumar; Maggipinto, Michael J.; Korza, George; Tutolo, Jessica W.; Giampetruzzi, Anthony; Le, Hien; Ma, Xin-Ming; Levine, Eric; Bishop, Brian; Kim, Duck O.; Kuwada, Shigeyuki; Carson, John H.

    2013-01-01

    In neurons, specific RNAs are assembled into granules, which are translated in dendrites, however the functional consequences of granule assembly are not known. Tumor overexpressed gene (TOG) is a granule-associated protein containing multiple binding sites for heterogeneous nuclear ribonucleoprotein (hnRNP) A2, another granule component that recognizes cis-acting sequences called hnRNP A2 response elements (A2REs) present in several granule RNAs. Translation in granules is sporadic, which is believed to reflect monosomal translation, with occasional bursts, which are believed to reflect polysomal translation. In this study, TOG expression was conditionally knocked out (TOG cKO) in mouse hippocampal neurons using cre/lox technology. In TOG cKO cultured neurons granule assembly and bursty translation of activity-regulated cytoskeletal associated (ARC) mRNA, an A2RE RNA, are disrupted. In TOG cKO brain slices synaptic sensitivity and long term potentiation (LTP) are reduced. TOG cKO mice exhibit hyperactivity, perseveration and impaired short term habituation. These results suggest that in hippocampal neurons TOG is required for granule assembly, granule translation and synaptic plasticity, and affects behavior. PMID:23936366

  2. Workshop on neural networks

    SciTech Connect

    Uhrig, R.E.; Emrich, M.L.

    1990-01-01

    The topics covered in this report are: Learning, Memory, and Artificial Neural Systems; Emerging Neural Network Technology; Neural Networks; Digital Signal Processing and Neural Networks; Application of Neural Networks to In-Core Fuel Management; Neural Networks in Process Control; Neural Network Applications in Image Processing; Neural Networks for Multi-Sensor Information Fusion; Neural Network Research in Instruments Controls Division; Neural Networks Research in the ORNL Engineering Physics and Mathematics Division; Neural Network Applications for Linear Programming; Neural Network Applications to Signal Processing and Diagnostics; Neural Networks in Filtering and Control; Neural Network Research at Tennessee Technological University; and Global Minima within the Hopfield Hypercube.

  3. Habituation contributes to within-session changes in free wheel running.

    PubMed Central

    Aoyama, K; McSweeney, F K

    2001-01-01

    Three experiments tested the hypothesis that habituation contributes to the regulation of wheel running. Rats ran in a wheel for 30-min sessions. Experiment 1 demonstrated spontaneous recovery. Rats ran more and the within-session decreases in running were smaller after 2 days of wheel deprivation than after 1 day. Experiment 2 demonstrated dishabituation. Running rate increased immediately after the termination of a brief extra event (application of the brake or flashing of the houselight). Experiment 3 demonstrated stimulus specificity. Rats completed the second half of the session in either the same wheel as the first half, or a different wheel. Second-half running was faster in the latter case. Within-session patterns of running were well described by equations that describe data from the habituation, motivation, and operant literatures. These results suggest that habituation contributes to the regulation of running. In fact, habituation provides a better explanation for the termination of wheel running than fatigue, the variable to which this termination is usually attributed. Overall, the present findings are consistent with the proposition that habituation and sensitization contribute to the regulation of several forms of motivated behavior. PMID:11768712

  4. Reversible online control of habitual behavior by optogenetic perturbation of medial prefrontal cortex.

    PubMed

    Smith, Kyle S; Virkud, Arti; Deisseroth, Karl; Graybiel, Ann M

    2012-11-13

    Habits tend to form slowly but, once formed, can have great stability. We probed these temporal characteristics of habitual behaviors by intervening optogenetically in forebrain habit circuits as rats performed well-ingrained habitual runs in a T-maze. We trained rats to perform a maze habit, confirmed the habitual behavior by devaluation tests, and then, during the maze runs (ca. 3 s), we disrupted population activity in a small region in the medial prefrontal cortex, the infralimbic cortex. In accordance with evidence that this region is necessary for the expression of habits, we found that this cortical disruption blocked habitual behavior. Notably, however, this blockade of habitual performance occurred on line, within an average of three trials (ca. 9 s of inhibition), and as soon as during the first trial (<3 s). During subsequent weeks of training, the rats acquired a new behavioral pattern. When we again imposed the same cortical perturbation, the rats regained the suppressed maze-running that typified the original habit, and, simultaneously, the more recently acquired habit was blocked. These online changes occurred within an average of two trials (ca. 6 s of infralimbic inhibition). Measured changes in generalized performance ability and motivation to consume reward were unaffected. This immediate toggling between breaking old habits and returning to them demonstrates that even semiautomatic behaviors are under cortical control and that this control occurs online, second by second. These temporal characteristics define a framework for uncovering cellular transitions between fixed and flexible behaviors, and corresponding disturbances in pathologies. PMID:23112197

  5. Learning and memory in Rhodnius prolixus: habituation and aversive operant conditioning of the proboscis extension response.

    PubMed

    Vinauger, Clément; Lallement, Hélène; Lazzari, Claudio R

    2013-03-01

    It has been largely accepted that the cognitive abilities of disease vector insects may have drastic consequences on parasite transmission. However, despite the research effort that has been invested in the study of learning and memory in haematophagous insects, hitherto few conclusive results have been obtained. Adapting procedures largely validated in Drosophila, honeybees and butterflies, we demonstrate here that the proboscis extension response (PER) of the haematophagous insect Rhodnius prolixus can be modulated by non-associative (habituation) and associative (aversive conditioning) learning forms. Thermal stimuli were used as both unconditional stimulus (appetitive temperatures) and negative reinforcement (thermal shock). In the first part of this work, the PER was habituated and dishabituated to thermal stimuli, demonstrating the true central processing of information and discarding motor fatigue or sensory adaptation. Habituation was revealed to be modulated by the spatial context. In the second part, bugs that were submitted to aversive operant conditioning stopped responding with PER to thermal stimulation more quickly than by habituation. They were able to use their training experience when tested up to 72 h later. Our work constitutes the first demonstration of PER habituation and conditioning in a blood-sucking insect and provides reproducible experimental tools for the study of the mechanisms underlying learning and memory in disease vectors. PMID:23408803

  6. Limitations of a habituation task to demonstrate discrimination of natural signals in songbirds.

    PubMed

    Ono, Satoko; Kagawa, Hiroko; Takahasi, Miki; Seki, Yoshimasa; Okanoya, Kazuo

    2015-06-01

    The habituation-dishabituation (HDH) paradigm is a common method used to examine animal cognition. Recent studies reported that spontaneous vocalizations could be used as an index of song familiarity and novelty in songbirds. However, these studies assigned only a few stimulus sets for all subjects, which might cause pseudoreplication. Therefore, we examined universality and general applicability of this method in Bengalese finches using a variety of stimulus sets. Seven unfamiliar conspecific songs were collected as a stimulus pool and a habituation song was randomly chosen for each subject. The subject was exposed to the habituation song repeatedly over 2h. During the test phase, the habituation song and a novel song randomly chosen from the stimulus pool were presented. We compared the degree of increase in call production during playback of those two songs. Although the degree was greater for the novel song compared with the habituation song in some birds, the trend was not consistent across all stimulus sets tested in these birds. Our results show that the HDH paradigm is not suitable to test song discrimination in songbirds unless precautions are taken to increase external validity by utilizing a variety of stimulus sets for each subject.

  7. Habituation of Sleep to Road Traffic Noise Observed not by Polygraphy but by Perception

    NASA Astrophysics Data System (ADS)

    KUROIWA, M.; XIN, P.; SUZUKI, S.; SASAZAWA, Y.; KAWADA, T.; TAMURA, Y.

    2002-02-01

    The habituation of sleep to road traffic noise was investigated. Habituation of sleep is improvement of sleep quality. Nine male students aged 19-21 were exposed to tape-recorded road traffic noise ofLeq 49·6 dB(A) in an experimental bedroom. Among 17 nights, the first four and the last three nights were non-exposure nights and the other consecutive 10 were exposure nights. The polygraphic sleep parameters were: sleep stages S1, S2, S(3+4), rapid eye movements (REM), and so on. Subjective sleep quality was assessed by five scales of a self-rating sleep questionnaire named the OSA, sleepiness (F1), sleep maintenance (F2), worry (F3), integrated sleep feeling (F4), and sleep initiation (F5). In this experiment, the habituation of sleep to road traffic noise was observed clearly in all of the subjective sleep parameters of the OSA, though all of the polygraphic sleep parameters showed little or no evidence of habituation. This suggests that habituation to noise has two aspects, sensation and perception mechanisms, corresponding to sleep polygraphy and to questionnaire respectively.

  8. Emotional Activation and Habituation During Imaginal Exposure for PTSD Among Women With Borderline Personality Disorder.

    PubMed

    Harned, Melanie S; Ruork, Allison K; Liu, Junny; Tkachuck, Mathew A

    2015-06-01

    The current study examined patterns and outcomes of emotional activation and habituation during imaginal exposure for posttraumatic stress disorder (PTSD). Participants were 16 women with borderline personality disorder (BPD), PTSD, and recent suicidal and/or self-injurious behavior who received imaginal exposure for PTSD concurrently with dialectical behavior therapy. The intensity of global distress and 6 specific emotions were assessed before and after imaginal exposure trials. Results indicated that significant within-session habituation (WSH) occurred for global distress (Hedge's g effect size = -2.52) and fear (g = -0.80), whereas significant between-session habituation (BSH) occurred for global distress (g = -2.18), fear (g = -1.89), guilt (g = -1.14), shame (g = -0.74), and disgust (g = -0.41). BSH significantly predicted PTSD diagnostic status at posttreatment, whereas activation and WSH were unrelated to outcome. Clients who remitted from PTSD showed significantly more BSH in global distress than nonremitters (η(2) = .39). In addition, remitters reported reductions in sadness and anger across trials, whereas sadness and anger increased for those who did not remit (η(2) = .54 and .40, respectively). Overall, BPD clients exhibited patterns of activation and habituation during imaginal exposure comparable to other client populations, and there was no evidence of persistent emotional engagement or habituation problems. PMID:26062135

  9. Utility of habituation-dishabituation procedure for comparative cognitive studies of Callithrix jacchus and Aotus spp.: preliminary assessments.

    PubMed

    Kaneko, Takaaki; Tomonaga, Masaki

    2008-06-01

    The utility of the habituation-dishabituation procedure was examined in the common marmosets (Callithrix jacchus) and the owl monkeys (Aotus spp.). The same movies were repeatedly shown to monkeys during an habituation phase, followed by a test phase during which monkeys were presented with a different movie. The time monkeys spent looking at the movie gradually decreased during the habituation phase and then significantly increased when they were presented the new movie. The limited findings indicate that these monkeys were sensitive to the habituation-dishabituation paradigm, suggesting that this procedure might be used to assess cognition and perception.

  10. Combinations of stroke neurorehabilitation to facilitate motor recovery: perspectives on Hebbian plasticity and homeostatic metaplasticity.

    PubMed

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2015-01-01

    Motor recovery after stroke involves developing new neural connections, acquiring new functions, and compensating for impairments. These processes are related to neural plasticity. Various novel stroke rehabilitation techniques based on basic science and clinical studies of neural plasticity have been developed to aid motor recovery. Current research aims to determine whether using combinations of these techniques can synergistically improve motor recovery. When different stroke neurorehabilitation therapies are combined, the timing of each therapeutic program must be considered to enable optimal neural plasticity. Synchronizing stroke rehabilitation with voluntary neural and/or muscle activity can lead to motor recovery by targeting Hebbian plasticity. This reinforces the neural connections between paretic muscles and the residual motor area. Homeostatic metaplasticity, which stabilizes the activity of neurons and neural circuits, can either augment or reduce the synergic effect depending on the timing of combination therapy and types of neurorehabilitation that are used. Moreover, the possibility that the threshold and degree of induced plasticity can be altered after stroke should be noted. This review focuses on the mechanisms underlying combinations of neurorehabilitation approaches and their future clinical applications. We suggest therapeutic approaches for cortical reorganization and maximal functional gain in patients with stroke, based on the processes of Hebbian plasticity and homeostatic metaplasticity. Few of the possible combinations of stroke neurorehabilitation have been tested experimentally; therefore, further studies are required to determine the appropriate combination for motor recovery.

  11. Combinations of stroke neurorehabilitation to facilitate motor recovery: perspectives on Hebbian plasticity and homeostatic metaplasticity

    PubMed Central

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2015-01-01

    Motor recovery after stroke involves developing new neural connections, acquiring new functions, and compensating for impairments. These processes are related to neural plasticity. Various novel stroke rehabilitation techniques based on basic science and clinical studies of neural plasticity have been developed to aid motor recovery. Current research aims to determine whether using combinations of these techniques can synergistically improve motor recovery. When different stroke neurorehabilitation therapies are combined, the timing of each therapeutic program must be considered to enable optimal neural plasticity. Synchronizing stroke rehabilitation with voluntary neural and/or muscle activity can lead to motor recovery by targeting Hebbian plasticity. This reinforces the neural connections between paretic muscles and the residual motor area. Homeostatic metaplasticity, which stabilizes the activity of neurons and neural circuits, can either augment or reduce the synergic effect depending on the timing of combination therapy and types of neurorehabilitation that are used. Moreover, the possibility that the threshold and degree of induced plasticity can be altered after stroke should be noted. This review focuses on the mechanisms underlying combinations of neurorehabilitation approaches and their future clinical applications. We suggest therapeutic approaches for cortical reorganization and maximal functional gain in patients with stroke, based on the processes of Hebbian plasticity and homeostatic metaplasticity. Few of the possible combinations of stroke neurorehabilitation have been tested experimentally; therefore, further studies are required to determine the appropriate combination for motor recovery. PMID:26157374

  12. Dopamine receptor DOP-4 modulates habituation to repetitive photoactivation of a C. elegans polymodal nociceptor.

    PubMed

    Ardiel, Evan L; Giles, Andrew C; Yu, Alex J; Lindsay, Theodore H; Lockery, Shawn R; Rankin, Catharine H

    2016-10-01

    Habituation is a highly conserved phenomenon that remains poorly understood at the molecular level. Invertebrate model systems, like Caenorhabditis elegans, can be a powerful tool for investigating this fundamental process. Here we established a high-throughput learning assay that used real-time computer vision software for behavioral tracking and optogenetics for stimulation of the C. elegans polymodal nociceptor, ASH. Photoactivation of ASH with ChR2 elicited backward locomotion and repetitive stimulation altered aspects of the response in a manner consistent with habituation. Recording photocurrents in ASH, we observed no evidence for light adaptation of ChR2. Furthermore, we ruled out fatigue by demonstrating that sensory input from the touch cells could dishabituate the ASH avoidance circuit. Food and dopamine signaling slowed habituation downstream from ASH excitation via D1-like dopamine receptor, DOP-4. This assay allows for large-scale genetic and drug screens investigating mechanisms of nociception modulation. PMID:27634141

  13. Dopamine receptor DOP-4 modulates habituation to repetitive photoactivation of a C. elegans polymodal nociceptor.

    PubMed

    Ardiel, Evan L; Giles, Andrew C; Yu, Alex J; Lindsay, Theodore H; Lockery, Shawn R; Rankin, Catharine H

    2016-10-01

    Habituation is a highly conserved phenomenon that remains poorly understood at the molecular level. Invertebrate model systems, like Caenorhabditis elegans, can be a powerful tool for investigating this fundamental process. Here we established a high-throughput learning assay that used real-time computer vision software for behavioral tracking and optogenetics for stimulation of the C. elegans polymodal nociceptor, ASH. Photoactivation of ASH with ChR2 elicited backward locomotion and repetitive stimulation altered aspects of the response in a manner consistent with habituation. Recording photocurrents in ASH, we observed no evidence for light adaptation of ChR2. Furthermore, we ruled out fatigue by demonstrating that sensory input from the touch cells could dishabituate the ASH avoidance circuit. Food and dopamine signaling slowed habituation downstream from ASH excitation via D1-like dopamine receptor, DOP-4. This assay allows for large-scale genetic and drug screens investigating mechanisms of nociception modulation.

  14. Reactivity to written mental arithmetic: effects of exercise lay-off and habituation.

    PubMed

    Szabo, A; Gauvin, L

    1992-03-01

    The present study examined (i) the effects of exercise lay-off on heart rate (HR) and subjective response to mental stress in 24 individuals highly committed to exercise, and (ii) psychophysiological reactivity to a challenging written mental arithmetic with subjectively controlled difficulty level. Subjects were tested on two occasions one week apart. Exercise withdrawal did not influence psychophysiological stress response. Second exposure to the mental arithmetic resulted in significantly lower HR response, due to habituation; higher pretask resting HR, due to anticipation of performance; and later onset in HR recovery. No changes in task performance and subjective measures were observed from session one to session two, indicating that habituation is rather a physiological than behavioral phenomenon. While these findings do not strengthen the link between exercise and stress response, they demonstrate the significant mediatory roles of habituation and anticipation in laboratory studies employing a test-retest design.

  15. Desensitization to Media Violence: Links With Habitual Media Violence Exposure, Aggressive Cognitions, and Aggressive Behavior

    PubMed Central

    Krahé, Barbara; Möller, Ingrid; Huesmann, L. Rowell; Kirwil, Lucyna; Felber, Juliane; Berger, Anja

    2015-01-01

    This study examined the links between desensitization to violent media stimuli and habitual media violence exposure as a predictor and aggressive cognitions and behavior as outcome variables. Two weeks after completing measures of habitual media violence exposure, trait aggression, trait arousability, and normative beliefs about aggression, undergraduates (N = 303) saw a violent film clip and a sad or a funny comparison clip. Skin conductance level (SCL) was measured continuously, and ratings of anxious and pleasant arousal were obtained after each clip. Following the clips, participants completed a lexical decision task to measure accessibility of aggressive cognitions and a competitive reaction time task to measure aggressive behavior. Habitual media violence exposure correlated negatively with SCL during violent clips and positively with pleasant arousal, response times for aggressive words, and trait aggression, but it was unrelated to anxious arousal and aggressive responding during the reaction time task. In path analyses controlling for trait aggression, normative beliefs, and trait arousability, habitual media violence exposure predicted faster accessibility of aggressive cognitions, partly mediated by higher pleasant arousal. Unprovoked aggression during the reaction time task was predicted by lower anxious arousal. Neither habitual media violence usage nor anxious or pleasant arousal predicted provoked aggression during the laboratory task, and SCL was unrelated to aggressive cognitions and behavior. No relations were found between habitual media violence viewing and arousal in response to the sad and funny film clips, and arousal in response to the sad and funny clips did not predict aggressive cognitions or aggressive behavior on the laboratory task. This suggests that the observed desensitization effects are specific to violent content. PMID:21186935

  16. Variety influences habituation of motivated behavior for food and energy intake in children123

    PubMed Central

    Epstein, Leonard H; Robinson, Jodie L; Temple, Jennifer L; Roemmich, James N; Marusewski, Angela L; Nadbrzuch, Rachel L

    2009-01-01

    Background: Research has shown that variety reduces the rate of habituation, or a general reduction in the rate of responding, for low-energy-density (LED) and high-energy-density (HED) foods. Objective: We assessed whether the effects of variety on habituation of motivation to eat are different in overweight and lean children. Design: Overweight and lean children (n = 84) were randomly assigned to groups that varied as to whether they received their favorite or a variety of LED or HED foods. Results: Habituation was slower for overweight than for nonoverweight children (P = 0.008), for a variety of foods than for the same foods (P < 0.001), and for LED than for HED foods (P < 0.001). Energy intake was greater for overweight than for nonoverweight children provided with variety (P = 0.004) and was greater for overweight or nonoverweight children provided with the same food (P < 0.001). A variety of HED foods increased energy intake more than did the same HED foods (P < 0.001); this increase was greater than energy intake with the same or a variety of LED foods (P < 0.001). Children who sensitized, or showed an increase in responding before habituating, showed slower habituation (P < 0.001) and consumed more energy (P = 0.039) than did children who did not sensitize. Conclusions: Habituation is influenced by variety of foods, and overweight children increase energy intake more with variety than do leaner children. Research is needed to evaluate mechanisms of how variety influences the motivation to eat and energy intake, and how the variety effect can be used to influence intake across multiple eating occasions in children. PMID:19176724

  17. Sleep extension normalizes ERP of waking auditory sensory gating in healthy habitually short sleeping individuals.

    PubMed

    Gumenyuk, Valentina; Korzyukov, Oleg; Roth, Thomas; Bowyer, Susan M; Drake, Christopher L

    2013-01-01

    Chronic sleep loss has been associated with increased daytime sleepiness, as well as impairments in memory and attentional processes. In the present study, we evaluated the neuronal changes of a pre-attentive process of wake auditory sensory gating, measured by brain event-related potential (ERP)--P50 in eight normal sleepers (NS) (habitual total sleep time (TST) 7 h 32 m) vs. eight chronic short sleeping individuals (SS) (habitual TST ≤6 h). To evaluate the effect of sleep extension on sensory gating, the extended sleep condition was performed in chronic short sleeping individuals. Thus, one week of time in bed (6 h 11 m) corresponding to habitual short sleep (hSS), and one week of extended time (∼ 8 h 25 m) in bed corresponding to extended sleep (eSS), were counterbalanced in the SS group. The gating ERP assessment was performed on the last day after each sleep condition week (normal sleep and habitual short and extended sleep), and was separated by one week with habitual total sleep time and monitored by a sleep diary. We found that amplitude of gating was lower in SS group compared to that in NS group (0.3 µV vs. 1.2 µV, at Cz electrode respectively). The results of the group × laterality interaction showed that the reduction of gating amplitude in the SS group was due to lower amplitude over the left hemisphere and central-midline sites relative to that in the NS group. After sleep extension the amplitude of gating increased in chronic short sleeping individuals relative to their habitual short sleep condition. The sleep condition × frontality interaction analysis confirmed that sleep extension significantly increased the amplitude of gating over frontal and central brain areas compared to parietal brain areas.

  18. Desensitization to media violence: links with habitual media violence exposure, aggressive cognitions, and aggressive behavior.

    PubMed

    Krahé, Barbara; Möller, Ingrid; Huesmann, L Rowell; Kirwil, Lucyna; Felber, Juliane; Berger, Anja

    2011-04-01

    This study examined the links between desensitization to violent media stimuli and habitual media violence exposure as a predictor and aggressive cognitions and behavior as outcome variables. Two weeks after completing measures of habitual media violence exposure, trait aggression, trait arousability, and normative beliefs about aggression, undergraduates (N = 303) saw a violent film clip and a sad or a funny comparison clip. Skin conductance level (SCL) was measured continuously, and ratings of anxious and pleasant arousal were obtained after each clip. Following the clips, participants completed a lexical decision task to measure accessibility of aggressive cognitions and a competitive reaction time task to measure aggressive behavior. Habitual media violence exposure correlated negatively with SCL during violent clips and positively with pleasant arousal, response times for aggressive words, and trait aggression, but it was unrelated to anxious arousal and aggressive responding during the reaction time task. In path analyses controlling for trait aggression, normative beliefs, and trait arousability, habitual media violence exposure predicted faster accessibility of aggressive cognitions, partly mediated by higher pleasant arousal. Unprovoked aggression during the reaction time task was predicted by lower anxious arousal. Neither habitual media violence usage nor anxious or pleasant arousal predicted provoked aggression during the laboratory task, and SCL was unrelated to aggressive cognitions and behavior. No relations were found between habitual media violence viewing and arousal in response to the sad and funny film clips, and arousal in response to the sad and funny clips did not predict aggressive cognitions or aggressive behavior on the laboratory task. This suggests that the observed desensitization effects are specific to violent content. PMID:21186935

  19. Desensitization to media violence: links with habitual media violence exposure, aggressive cognitions, and aggressive behavior.

    PubMed

    Krahé, Barbara; Möller, Ingrid; Huesmann, L Rowell; Kirwil, Lucyna; Felber, Juliane; Berger, Anja

    2011-04-01

    This study examined the links between desensitization to violent media stimuli and habitual media violence exposure as a predictor and aggressive cognitions and behavior as outcome variables. Two weeks after completing measures of habitual media violence exposure, trait aggression, trait arousability, and normative beliefs about aggression, undergraduates (N = 303) saw a violent film clip and a sad or a funny comparison clip. Skin conductance level (SCL) was measured continuously, and ratings of anxious and pleasant arousal were obtained after each clip. Following the clips, participants completed a lexical decision task to measure accessibility of aggressive cognitions and a competitive reaction time task to measure aggressive behavior. Habitual media violence exposure correlated negatively with SCL during violent clips and positively with pleasant arousal, response times for aggressive words, and trait aggression, but it was unrelated to anxious arousal and aggressive responding during the reaction time task. In path analyses controlling for trait aggression, normative beliefs, and trait arousability, habitual media violence exposure predicted faster accessibility of aggressive cognitions, partly mediated by higher pleasant arousal. Unprovoked aggression during the reaction time task was predicted by lower anxious arousal. Neither habitual media violence usage nor anxious or pleasant arousal predicted provoked aggression during the laboratory task, and SCL was unrelated to aggressive cognitions and behavior. No relations were found between habitual media violence viewing and arousal in response to the sad and funny film clips, and arousal in response to the sad and funny clips did not predict aggressive cognitions or aggressive behavior on the laboratory task. This suggests that the observed desensitization effects are specific to violent content.

  20. General Learning Ability Regulates Exploration Through its Influence on Rate of Habituation

    PubMed Central

    Light, Kenneth R.; Grossman, Henya; Kolata, Stefan; Matzel, Louis D.

    2011-01-01

    “General intelligence” is purported to influence diverse domain-specific learning abilities in humans, and previous research indicates that an analogous trait is expressed in CD-1 outbred mice. In humans and mice, exploratory tendencies are predictive of general cognitive abilities, such that higher cognitive abilities are associated with elevated levels of exploration. However, in mice, repeated exposure to novel environments outside the home cage has been found to up-regulate exploratory tendencies but has no commensurate effect on general learning abilities, suggesting that exploratory tendencies do not causally influence general cognitive performance. This leaves open the question of what is responsible for the robust relationship observed between exploration and general learning abilities? In the present experiments, we find that differential rates of habituation (e.g., to a novel open field) between animals of high and low general learning abilities accounts for the relationship between exploration and learning abilities. First, we up-regulated exploration by exposing mice to a series of novel environments. Similar to its lack of effect on learning tasks, this up-regulation of exploration had no commensurate effect on habituation to novel objects or stimuli. Next we examined the relationship between general learning abilities and exploration under conditions where habituation had a high or low impact on exploratory behaviors. A strong correlation between general learning abilities and exploration was observed under conditions where the levels of habituation (to a novel object or an open field) between animals of high and low general learning abilities were allowed to vary. However, this same correlation was attenuated when the level of habituation attained by animals of high and low general learning abilities was asymptotic or held constant across animals. In total, these results indicate that the relationship between exploration and general learning

  1. Yellowstone grizzly bear mortality, human habituation, and whitebark pine seed crops

    USGS Publications Warehouse

    Mattson, David J.; Blanchard, Bonnie M.; Knight, Richard R.

    1992-01-01

    The Yellowstone grizzly bear (Ursus arctos horribilis) population may be extirpated during the next 100-200 years unless mortality rates stabilize and remain at acceptable low levels. Consequently, we analyzed relationships between Yellowstone grizzly bear mortality and frequency of human habituation among bears and size of the whitebark pine (Pinus albicaulis) seed crop. During years of large seed crops, bears used areas within 5 km of roads and 8 km of developments half as intensively as during years of small seed crops because whitebark pine's high elevation distribution is typically remote from human facilities. On average, management trappings of bears were 6.2 times higher, mortality of adult females 2.3 times higher, and mortality of subadult males 3.3 times higher during years of small seed crops. We hypothesize that high mortality of adult females and subadult males during small seed crop years was a consequence of their tendency to range closest (of all sex-age cohorts) to human facilities; they also had a higher frequency of human habituation compared with adult males. We also hypothesize that low morality among subadult females during small seed crop years was a result of fewer energetic stressors compared with adult females and greater familiarity with their range compared with subadult males; mortality was low even though they ranged close to humans and exhibited a high frequency of human habituation. Human-habituated and food-conditioned bears were 2.9 times as likely to range within 4 km of developments and 3.1 times as often killed by humans compared with nonhabituated bears. We argue that destruction of habituated bears that use native foods near humans results in a decline in the overall ability of bears to use available habitat; and that the number and extent of human facilities in occupied grizzly bear habitat needs to be minimized unless habituated bears are preserved and successful ways to manage the associated risks to humans are developed.

  2. Sleep extension normalizes ERP of waking auditory sensory gating in healthy habitually short sleeping individuals.

    PubMed

    Gumenyuk, Valentina; Korzyukov, Oleg; Roth, Thomas; Bowyer, Susan M; Drake, Christopher L

    2013-01-01

    Chronic sleep loss has been associated with increased daytime sleepiness, as well as impairments in memory and attentional processes. In the present study, we evaluated the neuronal changes of a pre-attentive process of wake auditory sensory gating, measured by brain event-related potential (ERP)--P50 in eight normal sleepers (NS) (habitual total sleep time (TST) 7 h 32 m) vs. eight chronic short sleeping individuals (SS) (habitual TST ≤6 h). To evaluate the effect of sleep extension on sensory gating, the extended sleep condition was performed in chronic short sleeping individuals. Thus, one week of time in bed (6 h 11 m) corresponding to habitual short sleep (hSS), and one week of extended time (∼ 8 h 25 m) in bed corresponding to extended sleep (eSS), were counterbalanced in the SS group. The gating ERP assessment was performed on the last day after each sleep condition week (normal sleep and habitual short and extended sleep), and was separated by one week with habitual total sleep time and monitored by a sleep diary. We found that amplitude of gating was lower in SS group compared to that in NS group (0.3 µV vs. 1.2 µV, at Cz electrode respectively). The results of the group × laterality interaction showed that the reduction of gating amplitude in the SS group was due to lower amplitude over the left hemisphere and central-midline sites relative to that in the NS group. After sleep extension the amplitude of gating increased in chronic short sleeping individuals relative to their habitual short sleep condition. The sleep condition × frontality interaction analysis confirmed that sleep extension significantly increased the amplitude of gating over frontal and central brain areas compared to parietal brain areas. PMID:23520548

  3. Periodontal Plastic Surgery

    MedlinePlus

    ... Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain ... Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain ...

  4. Plasticity and Geotechnics

    NASA Astrophysics Data System (ADS)

    Yu, Hai-Sui

    Plasticity and Geotechnics is the first attempt to summarize and present, in one volume, the major developments achieved to date in the field of plasticity theory for geotechnical materials and its applications to geotechnical analysis and design.

  5. Plastic Surgery for Teenagers

    MedlinePlus

    ... or severe acne and scarring. Teens frequently gain self-esteem and confidence when their physical problems are corrected. ... art as a helpful index of anxiety and self-esteem with plastic surgery. Plastic and Reconstructive Surgery 2002. ...

  6. Plastic casting resin poisoning

    MedlinePlus

    Epoxy poisoning; Resin poisoning ... Epoxy and resin can be poisonous if they are swallowed or their fumes are breathed in. ... Plastic casting resins are found in various plastic casting resin products.

  7. Ear Plastic Surgery

    MedlinePlus

    ... Meeting Calendar Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...

  8. Plastic encapsulated parts

    SciTech Connect

    Castillo, T.

    1994-10-01

    Plastic semiconductor packages were characterized as possible alternatives for canned devices, which are susceptible to internal shorts caused by conductive particles. Highly accelerated stress testing (HAST) as well as electrical and mechanical testing were conducted on plastic technology devices.

  9. Prevalence of oral malodor and the relationship with habitual mouth breathing in children.

    PubMed

    Kanehira, Takashi; Takehara, Junji; Takahashi, Dairo; Honda, Okahito; Morita, Manabu

    2004-01-01

    The prevalence of oral malodor and association of habitual mouth breathing with oral malodor were investigated in children residing in rural areas. One hundred and nineteen children participated in this study. A sulfide monitor and organoleptic method were used to evaluate oral malodor. About 8% of children had a sulfide level in mouth air above the socially acceptable limit (75 ppb). Habitual mouth breathing was a factor contributing to oral malodor. Oral malodor was not significantly correlated with plaque index, history of caries or frequency of toothbrushing.

  10. Opposing Effects of Neuronal Activity on Structural Plasticity

    PubMed Central

    Fauth, Michael; Tetzlaff, Christian

    2016-01-01

    The connectivity of the brain is continuously adjusted to new environmental influences by several activity-dependent adaptive processes. The most investigated adaptive mechanism is activity-dependent functional or synaptic plasticity regulating the transmission efficacy of existing synapses. Another important but less prominently discussed adaptive process is structural plasticity, which changes the connectivity by the formation and deletion of synapses. In this review, we show, based on experimental evidence, that structural plasticity can be classified similar to synaptic plasticity into two categories: (i) Hebbian structural plasticity, which leads to an increase (decrease) of the number of synapses during phases of high (low) neuronal activity and (ii) homeostatic structural plasticity, which balances these changes by removing and adding synapses. Furthermore, based on experimental and theoretical insights, we argue that each type of structural plasticity fulfills a different function. While Hebbian structural changes enhance memory lifetime, storage capacity, and memory robustness, homeostatic structural plasticity self-organizes the connectivity of the neural network to assure stability. However, the link between functional synaptic and structural plasticity as well as the detailed interactions between Hebbian and homeostatic structural plasticity are more complex. This implies even richer dynamics requiring further experimental and theoretical investigations. PMID:27445713

  11. Opposing Effects of Neuronal Activity on Structural Plasticity.

    PubMed

    Fauth, Michael; Tetzlaff, Christian

    2016-01-01

    The connectivity of the brain is continuously adjusted to new environmental influences by several activity-dependent adaptive processes. The most investigated adaptive mechanism is activity-dependent functional or synaptic plasticity regulating the transmission efficacy of existing synapses. Another important but less prominently discussed adaptive process is structural plasticity, which changes the connectivity by the formation and deletion of synapses. In this review, we show, based on experimental evidence, that structural plasticity can be classified similar to synaptic plasticity into two categories: (i) Hebbian structural plasticity, which leads to an increase (decrease) of the number of synapses during phases of high (low) neuronal activity and (ii) homeostatic structural plasticity, which balances these changes by removing and adding synapses. Furthermore, based on experimental and theoretical insights, we argue that each type of structural plasticity fulfills a different function. While Hebbian structural changes enhance memory lifetime, storage capacity, and memory robustness, homeostatic structural plasticity self-organizes the connectivity of the neural network to assure stability. However, the link between functional synaptic and structural plasticity as well as the detailed interactions between Hebbian and homeostatic structural plasticity are more complex. This implies even richer dynamics requiring further experimental and theoretical investigations. PMID:27445713

  12. Tomorrow's Plastic World

    ERIC Educational Resources Information Center

    Macdonald, Averil

    2005-01-01

    Far from being just cheap packaging materials, plastics may be the materials of tomorrow. Plastic can conduct electricity, and this opens up a host of high-tech possibilities in the home and in energy generation. These possibilities are discussed here along with how plastic can be recycled and perhaps even grown.

  13. Processing of plastics

    PubMed Central

    Spaak, Albert

    1975-01-01

    An overview is given of the processing of plastic materials from the handling of polymers in the pellet and powder form to manufacturing of a plastic fabricated product. Various types of equipment used and melt processing ranges of various polymer formulations to make the myriad of plastic products that are commercially available are discussed. PMID:1175556

  14. Plastics in Building.

    ERIC Educational Resources Information Center

    Skeist, Irving, Ed.

    The evaluation and use of plastics in the construction industry are explained. The contributors offer extensive, timely, and thoroughly researched data on the chemistry, properties, functions, engineering behavior, and specific applications of plastics to building requirements. The major subjects discussed in depth are--(1) the role of plastics in…

  15. Evolvable synthetic neural system

    NASA Technical Reports Server (NTRS)

    Curtis, Steven A. (Inventor)

    2009-01-01

    An evolvable synthetic neural system includes an evolvable neural interface operably coupled to at least one neural basis function. Each neural basis function includes an evolvable neural interface operably coupled to a heuristic neural system to perform high-level functions and an autonomic neural system to perform low-level functions. In some embodiments, the evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy.

  16. The endocannabinoid system in anxiety, fear memory and habituation

    PubMed Central

    Ruehle, S; Rey, A Aparisi; Remmers, F

    2012-01-01

    Evidence for the involvement of the endocannabinoid system (ECS) in anxiety and fear has been accumulated, providing leads for novel therapeutic approaches. In anxiety, a bidirectional influence of the ECS has been reported, whereby anxiolytic and anxiogenic responses have been obtained after both increases and decreases of the endocannabinoid tone. The recently developed genetic tools have revealed different but complementary roles for the cannabinoid type 1 (CB1) receptor on GABAergic and glutamatergic neuronal populations. This dual functionality, together with the plasticity of CB1 receptor expression, particularly on GABAergic neurons, as induced by stressful and rewarding experiences, gives the ECS a unique regulatory capacity for maintaining emotional homeostasis. However, the promiscuity of the endogenous ligands of the CB1 receptor complicates the interpretation of experimental data concerning ECS and anxiety. In fear memory paradigms, the ECS is mostly involved in the two opposing processes of reconsolidation and extinction of the fear memory. Whereas ECS activation deteriorates reconsolidation, proper extinction depends on intact CB1 receptor signalling. Thus, both for anxiety and fear memory processing, endocannabinoid signalling may ensure an appropriate reaction to stressful events. Therefore, the ECS can be considered as a regulatory buffer system for emotional responses. PMID:21768162

  17. Neural Networks

    SciTech Connect

    Smith, Patrick I.

    2003-09-23

    Physicists use large detectors to measure particles created in high-energy collisions at particle accelerators. These detectors typically produce signals indicating either where ionization occurs along the path of the particle, or where energy is deposited by the particle. The data produced by these signals is fed into pattern recognition programs to try to identify what particles were produced, and to measure the energy and direction of these particles. Ideally, there are many techniques used in this pattern recognition software. One technique, neural networks, is particularly suitable for identifying what type of particle caused by a set of energy deposits. Neural networks can derive meaning from complicated or imprecise data, extract patterns, and detect trends that are too complex to be noticed by either humans or other computer related processes. To assist in the advancement of this technology, Physicists use a tool kit to experiment with several neural network techniques. The goal of this research is interface a neural network tool kit into Java Analysis Studio (JAS3), an application that allows data to be analyzed from any experiment. As the final result, a physicist will have the ability to train, test, and implement a neural network with the desired output while using JAS3 to analyze the results or output. Before an implementation of a neural network can take place, a firm understanding of what a neural network is and how it works is beneficial. A neural network is an artificial representation of the human brain that tries to simulate the learning process [5]. It is also important to think of the word artificial in that definition as computer programs that use calculations during the learning process. In short, a neural network learns by representative examples. Perhaps the easiest way to describe the way neural networks learn is to explain how the human brain functions. The human brain contains billions of neural cells that are responsible for processing

  18. Influence of Estrogen Receptor α Polymorphisms on Bone Density in Response to Habitual Exercise in Japanese Postmenopausal Women

    PubMed Central

    Kondo, Hiroyo; Nagatomo, Fumiko; Ishihara, Akihiko

    2014-01-01

    Estrogen receptor α (ERα) is one of candidate genes for osteoporosis. This study examined the influence of ERα gene, PvuII, and XbaI genotypes on bone density of calcaneus in response to habitual exercise. ERα polymorphisms were detected using PvuII and XbaI restriction enzymes in 316 Japanese postmenopausal women. The bone density was significantly lower in the women carrying PP, pp, or xx genotype without habitual exercise than in the age-matched women without those genotypes. The women carrying Pp genotype without habitual exercise had normal bone density compared to those without Pp genotype. The women carrying PPxx or ppxx polymorphism without habitual exercise had low bone density compared to those with habitual exercise. Thus, the reduction of bone density was attenuated in the women carrying PPxx or ppxx with habitual exercise. In addition, habitual exercise was highly effective for the bone density in the women carrying xx homozygote. These findings indicate that analyses of XbaI and PvuII polymorphisms of ERα may be useful to predict the effect of exercise on bone density, and habitual exercise attenuates the reduction of bone density in women with some genotypes. PMID:25152917

  19. Biodegradability of Plastics

    PubMed Central

    Tokiwa, Yutaka; Calabia, Buenaventurada P.; Ugwu, Charles U.; Aiba, Seiichi

    2009-01-01

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed. PMID:19865515

  20. Biodegradability of plastics.

    PubMed

    Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi

    2009-08-26

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  1. a Heterosynaptic Learning Rule for Neural Networks

    NASA Astrophysics Data System (ADS)

    Emmert-Streib, Frank

    In this article we introduce a novel stochastic Hebb-like learning rule for neural networks that is neurobiologically motivated. This learning rule combines features of unsupervised (Hebbian) and supervised (reinforcement) learning and is stochastic with respect to the selection of the time points when a synapse is modified. Moreover, the learning rule does not only affect the synapse between pre- and postsynaptic neuron, which is called homosynaptic plasticity, but effects also further remote synapses of the pre- and postsynaptic neuron. This more complex form of synaptic plasticity has recently come under investigations in neurobiology and is called heterosynaptic plasticity. We demonstrate that this learning rule is useful in training neural networks by learning parity functions including the exclusive-or (XOR) mapping in a multilayer feed-forward network. We find, that our stochastic learning rule works well, even in the presence of noise. Importantly, the mean learning time increases with the number of patterns to be learned polynomially, indicating efficient learning.

  2. Augmentation-related brain plasticity.

    PubMed

    Di Pino, Giovanni; Maravita, Angelo; Zollo, Loredana; Guglielmelli, Eugenio; Di Lazzaro, Vincenzo

    2014-01-01

    Today, the anthropomorphism of the tools and the development of neural interfaces require reconsidering the concept of human-tools interaction in the framework of human augmentation. This review analyses the plastic process that the brain undergoes when it comes into contact with augmenting artificial sensors and effectors and, on the other hand, the changes that the use of external augmenting devices produces in the brain. Hitherto, few studies investigated the neural correlates of augmentation, but clues on it can be borrowed from logically-related paradigms: sensorimotor training, cognitive enhancement, cross-modal plasticity, sensorimotor functional substitution, use and embodiment of tools. Augmentation modifies function and structure of a number of areas, i.e., primary sensory cortices shape their receptive fields to become sensitive to novel inputs. Motor areas adapt the neuroprosthesis representation firing-rate to refine kinematics. As for normal motor outputs, the learning process recruits motor and premotor cortices and the acquisition of proficiency decreases attentional recruitment, focuses the activity on sensorimotor areas and increases the basal ganglia drive on the cortex. Augmentation deeply relies on the frontoparietal network. In particular, premotor cortex is involved in learning the control of an external effector and owns the tool motor representation, while the intraparietal sulcus extracts its visual features. In these areas, multisensory integration neurons enlarge their receptive fields to embody supernumerary limbs. For operating an anthropomorphic neuroprosthesis, the mirror system is required to understand the meaning of the action, the cerebellum for the formation of its internal model and the insula for its interoception. In conclusion, anthropomorphic sensorized devices can provide the critical sensory afferences to evolve the exploitation of tools through their embodiment, reshaping the body representation and the sense of the self

  3. Augmentation-related brain plasticity

    PubMed Central

    Di Pino, Giovanni; Maravita, Angelo; Zollo, Loredana; Guglielmelli, Eugenio; Di Lazzaro, Vincenzo

    2014-01-01

    Today, the anthropomorphism of the tools and the development of neural interfaces require reconsidering the concept of human-tools interaction in the framework of human augmentation. This review analyses the plastic process that the brain undergoes when it comes into contact with augmenting artificial sensors and effectors and, on the other hand, the changes that the use of external augmenting devices produces in the brain. Hitherto, few studies investigated the neural correlates of augmentation, but clues on it can be borrowed from logically-related paradigms: sensorimotor training, cognitive enhancement, cross-modal plasticity, sensorimotor functional substitution, use and embodiment of tools. Augmentation modifies function and structure of a number of areas, i.e., primary sensory cortices shape their receptive fields to become sensitive to novel inputs. Motor areas adapt the neuroprosthesis representation firing-rate to refine kinematics. As for normal motor outputs, the learning process recruits motor and premotor cortices and the acquisition of proficiency decreases attentional recruitment, focuses the activity on sensorimotor areas and increases the basal ganglia drive on the cortex. Augmentation deeply relies on the frontoparietal network. In particular, premotor cortex is involved in learning the control of an external effector and owns the tool motor representation, while the intraparietal sulcus extracts its visual features. In these areas, multisensory integration neurons enlarge their receptive fields to embody supernumerary limbs. For operating an anthropomorphic neuroprosthesis, the mirror system is required to understand the meaning of the action, the cerebellum for the formation of its internal model and the insula for its interoception. In conclusion, anthropomorphic sensorized devices can provide the critical sensory afferences to evolve the exploitation of tools through their embodiment, reshaping the body representation and the sense of the self

  4. Augmentation-related brain plasticity.

    PubMed

    Di Pino, Giovanni; Maravita, Angelo; Zollo, Loredana; Guglielmelli, Eugenio; Di Lazzaro, Vincenzo

    2014-01-01

    Today, the anthropomorphism of the tools and the development of neural interfaces require reconsidering the concept of human-tools interaction in the framework of human augmentation. This review analyses the plastic process that the brain undergoes when it comes into contact with augmenting artificial sensors and effectors and, on the other hand, the changes that the use of external augmenting devices produces in the brain. Hitherto, few studies investigated the neural correlates of augmentation, but clues on it can be borrowed from logically-related paradigms: sensorimotor training, cognitive enhancement, cross-modal plasticity, sensorimotor functional substitution, use and embodiment of tools. Augmentation modifies function and structure of a number of areas, i.e., primary sensory cortices shape their receptive fields to become sensitive to novel inputs. Motor areas adapt the neuroprosthesis representation firing-rate to refine kinematics. As for normal motor outputs, the learning process recruits motor and premotor cortices and the acquisition of proficiency decreases attentional recruitment, focuses the activity on sensorimotor areas and increases the basal ganglia drive on the cortex. Augmentation deeply relies on the frontoparietal network. In particular, premotor cortex is involved in learning the control of an external effector and owns the tool motor representation, while the intraparietal sulcus extracts its visual features. In these areas, multisensory integration neurons enlarge their receptive fields to embody supernumerary limbs. For operating an anthropomorphic neuroprosthesis, the mirror system is required to understand the meaning of the action, the cerebellum for the formation of its internal model and the insula for its interoception. In conclusion, anthropomorphic sensorized devices can provide the critical sensory afferences to evolve the exploitation of tools through their embodiment, reshaping the body representation and the sense of the self.

  5. Variation in Foot Strike Patterns among Habitually Barefoot and Shod Runners in Kenya.

    PubMed

    Lieberman, Daniel E; Castillo, Eric R; Otarola-Castillo, Erik; Sang, Meshack K; Sigei, Timothy K; Ojiambo, Robert; Okutoyi, Paul; Pitsiladis, Yannis

    2015-01-01

    Runners are often categorized as forefoot, midfoot or rearfoot strikers, but how much and why do individuals vary in foot strike patterns when running on level terrain? This study used general linear mixed-effects models to explore both intra- and inter-individual variations in foot strike pattern among 48 Kalenjin-speaking participants from Kenya who varied in age, sex, body mass, height, running history, and habitual use of footwear. High speed video was used to measure lower extremity kinematics at ground contact in the sagittal plane while participants ran down 13 meter-long tracks with three variables independently controlled: speed, track stiffness, and step frequency. 72% of the habitually barefoot and 32% of the habitually shod participants used multiple strike types, with significantly higher levels of foot strike variation among individuals who ran less frequently and who used lower step frequencies. There was no effect of sex, age, height or weight on foot strike angle, but individuals were more likely to midfoot or forefoot strike when they ran on a stiff surface, had a high preferred stride frequency, were habitually barefoot, and had more experience running. It is hypothesized that strike type variation during running, including a more frequent use of forefoot and midfoot strikes, used to be greater before the introduction of cushioned shoes and paved surfaces. PMID:26154285

  6. Habituation of self-motion perception following unidirectional angular velocity steps.

    PubMed

    Clément, Gilles; Terlevic, Robert

    2016-09-01

    We investigated whether the perceived angular velocity following velocity steps of 80°/s in the dark decreased with the repetition of the stimulation in the same direction. The perceptual response to velocity steps in the opposite direction was also compared before and after this unidirectional habituation training. Participants indicated their perceived angular velocity by clicking on a wireless mouse every time they felt that they had rotated by 90°. The prehabituation perceptual response decayed exponentially with a time constant of 23.9 s. After 100 velocity steps in the same direction, this time constant was 12.9 s. The time constant after velocity steps in the opposite direction was 13.4 s, indicating that the habituation of the sensation of rotation is not direction specific. The peak velocity of the perceptual response was not affected by the habituation training. The differences between the habituation characteristics of self-motion perception and eye movements confirm that different velocity storage mechanisms mediate ocular and perceptual responses. PMID:27391426

  7. Habitual Sleep Duration and Self-Perceptions of the Need to Achieve.

    ERIC Educational Resources Information Center

    Pellegrini, Robert J.; And Others

    Two hypotheses were developed in an attempt to organize and clarify the conceptual basis for studies of relationships between patterns of habitual sleep duration and self-perceptions of the need to achieve. A non-specific arousal (N-SA) hypothesis presumes that short sleepers show more vigor, more general anxiety, incline more toward development…

  8. Habituation of Premonitory Sensations during Exposure and Response Prevention Treatment in Tourette's Syndrome

    ERIC Educational Resources Information Center

    Verdellen, Cara W. J.; Hoogduin, Cees A. L.; Kato, Bernet S.; Keijsers, Ger P. J.; Cath, Danielle C.; Hoijtink, Herbert B.

    2008-01-01

    Exposure to premonitory sensations and response prevention of tics (ER) has been shown to be a promising new treatment for Tourette's syndrome (TS). The present study tested the hypothesis that habituation to unpleasant premonitory sensations associated with the tic is an underlying mechanism of change in ER. Patients rated the severity of…

  9. Dynamic Changes in Reinforcer Effectiveness: Satiation and Habituation Have Different Implications for Theory and Practice

    ERIC Educational Resources Information Center

    McSweeney, Frances K.

    2004-01-01

    Reinforcers lose their effectiveness when they are presented repeatedly. Early researchers labeled this loss of effectiveness as "satiation" without conducting an experimental analysis. When such an analysis is conducted, "habituation" provides a more precise and empirically accurate label for the changes in reinforcer effectiveness. This paper…

  10. Dopamine Receptor DOP-4 Modulates Habituation to Repetitive Photoactivation of a "C. elegans" Polymodal Nociceptor

    ERIC Educational Resources Information Center

    Ardiel, Evan L.; Giles, Andrew C.; Yu, Alex J.; Lindsay, Theodore H.; Lockery, Shawn R.; Rankin, Catharine H.

    2016-01-01

    Habituation is a highly conserved phenomenon that remains poorly understood at the molecular level. Invertebrate model systems, like "Caenorhabditis elegans," can be a powerful tool for investigating this fundamental process. Here we established a high-throughput learning assay that used real-time computer vision software for behavioral…

  11. Variation in Foot Strike Patterns among Habitually Barefoot and Shod Runners in Kenya

    PubMed Central

    Lieberman, Daniel E.; Castillo, Eric R.; Otarola-Castillo, Erik; Sang, Meshack K.; Sigei, Timothy K.; Ojiambo, Robert; Okutoyi, Paul; Pitsiladis, Yannis

    2015-01-01

    Runners are often categorized as forefoot, midfoot or rearfoot strikers, but how much and why do individuals vary in foot strike patterns when running on level terrain? This study used general linear mixed-effects models to explore both intra- and inter-individual variations in foot strike pattern among 48 Kalenjin-speaking participants from Kenya who varied in age, sex, body mass, height, running history, and habitual use of footwear. High speed video was used to measure lower extremity kinematics at ground contact in the sagittal plane while participants ran down 13 meter-long tracks with three variables independently controlled: speed, track stiffness, and step frequency. 72% of the habitually barefoot and 32% of the habitually shod participants used multiple strike types, with significantly higher levels of foot strike variation among individuals who ran less frequently and who used lower step frequencies. There was no effect of sex, age, height or weight on foot strike angle, but individuals were more likely to midfoot or forefoot strike when they ran on a stiff surface, had a high preferred stride frequency, were habitually barefoot, and had more experience running. It is hypothesized that strike type variation during running, including a more frequent use of forefoot and midfoot strikes, used to be greater before the introduction of cushioned shoes and paved surfaces. PMID:26154285

  12. Maternal Alcohol Use and Neonatal Habituation Assessed with the Brazelton Scale.

    ERIC Educational Resources Information Center

    Streissguth, Ann Pytkowicz; And Others

    1983-01-01

    Maternal alcohol use in mid-pregnancy was significantly related to poorer habituation and increased low arousal in newborn infants, even after adjusting for smoking and caffeine use by mothers, maternal age and nutrition during pregnancy, sex and age of the infant, and obstetric medication. (Author/RH)

  13. The "Prawn-in-the-Tube" Procedure in the Cuttlefish: Habituation or Passive Avoidance Learning?

    ERIC Educational Resources Information Center

    Dickel, Ludovic; Chichery, Marie-Paule; Agin, Veronique; Chichery, Raymond

    2006-01-01

    This study examines whether or not habituation contributes to the regulation of the inhibition of predatory behavior observed during the "prawn-in-the-tube" training procedure. When presented with prawns that are visible behind glass but untouchable, cuttlefish promptly learn to inhibit their capture attempts. The first three experiments…

  14. The Influence of Agenda-Based and Habitual Processes on Item Selection during Study

    ERIC Educational Resources Information Center

    Dunlosky, John; Ariel, Robert

    2011-01-01

    Research on study-time allocation has largely focused on agenda-based regulation, such as whether learners select items for study that are in their region of proximal learning. In 4 experiments, the authors evaluated the contribution of habitual responding to study-time allocation (e.g., reading from left to right). In Experiments 1 and 2,…

  15. Comparison of Hypnotherapy with Systematic Relaxation in the Treatment of Cigarette Habituation.

    ERIC Educational Resources Information Center

    Schubert, Donald K.

    1983-01-01

    Studied the effectiveness of hypnosis in the treatment of cigarette habituation. Volunteers (N=87) were randomly assigned to hypnosis, relaxation, or waiting list control groups. Hypnosis was found to be superior to relaxation only for subjects high in hypnotic susceptibility. Those who quit smoking increased food consumption. (Author/JAC)

  16. Habituation of the initial responses to cold water immersion in humans: a central or peripheral mechanism?

    PubMed Central

    Tipton, Michael J; Eglin, Clare M; Golden, Frank St C

    1998-01-01

    The initial respiratory and cardiac responses to cold water immersion are thought to be responsible for a significant number of open water deaths each year. Previous research has demonstrated that the magnitude of these responses can be reduced by repeated immersions in cold waterwhether the site of habituation is central or peripheral.Two groups of subjects undertook two 3 min head-out immersions in stirred water at 10 °C of the right-hand side of the body (R). Between these two immersions (3 whole days) the control group (n = 7) were not exposed to cold water, but the habituation group (n = 8) undertook a further six 3 min head-out immersions in stirred water at 10 °C of the left-hand side of the body (L).Repeated L immersions reduced (P < 0.01) the heart rate, respiratory frequency and volume responses. During the second R immersion a reduction (P < 0.05) in the magnitude of the responses evoked was seen in the habituation group but not in the control group, despite both groups having identical skin temperature profiles.It is concluded that the mechanisms involved in producing habituation of the initial responses are located more centrally than the peripheral receptors. PMID:9763650

  17. Ultrastructural and histochemical markers of endometrial secretion induction in habitual miscarriage.

    PubMed

    Ilizarova, N A; Marinkin, I O; Ageeva, T A; Bgatova, N P; Kuleshov, V M; Aidagulova, S V

    2009-10-01

    Biphasic hormone therapy at the stage of pre-gestation treatment of patients with habitual miscarriages stimulates the expression of progesterone receptors in the endometrium during the secretory phase of the menstrual cycle with full-value ultrastructural rearrangement of the endometrial glandular components in comparison with the patients receiving metabolic therapy alone. PMID:20396766

  18. Brain mechanisms of short-term habituation and sensitization toward dyspnea

    PubMed Central

    Stoeckel, M. Cornelia; Esser, Roland W.; Gamer, Matthias; Büchel, Christian; von Leupoldt, Andreas

    2015-01-01

    Dyspnea is a prevalent and threatening cardinal symptom in many diseases including asthma. Whether patients suffering from dyspnea show habituation or sensitization toward repeated experiences of dyspnea is relevant for both quality of life and treatment success. Understanding the mechanisms, including the underlying brain activation patterns, that determine the dynamics of dyspnea perception seems crucial for the improvement of treatment and rehabilitation. Toward this aim, we investigated the interplay between short-term changes of dyspnea perception and changes of related brain activation. Healthy individuals underwent repeated blocks of resistive load induced dyspnea with parallel acquisition of functional magnetic resonance imaging data. Late vs. early ratings on dyspnea intensity and unpleasantness were correlated with late vs. early brain activation for both, dyspnea anticipation and dyspnea perception. Individual trait and state anxiety were determined using questionnaire data. Our results indicate an involvement of the orbitofrontal cortex (OFC), midbrain/periaqueductal gray (PAG) and anterior insular cortex in habituation/sensitization toward dyspnea. Changes in the anterior insular cortex were particularly linked to changes in dyspnea unpleasantness. Changes of both dyspnea intensity and unpleasantness were positively correlated with state and trait anxiety. Our findings are in line with the suggested relationship between the anterior insular cortex and dyspnea unpleasantness. They further support the notion that habituation/sensitization toward dyspnea is influenced by anxiety. Our study extends the known role of the midbrain/PAG in anti-nociception to an additional involvement in habituation/sensitization toward dyspnea and suggests an interplay with the OFC. PMID:26082746

  19. Habituation of self-motion perception following unidirectional angular velocity steps.

    PubMed

    Clément, Gilles; Terlevic, Robert

    2016-09-01

    We investigated whether the perceived angular velocity following velocity steps of 80°/s in the dark decreased with the repetition of the stimulation in the same direction. The perceptual response to velocity steps in the opposite direction was also compared before and after this unidirectional habituation training. Participants indicated their perceived angular velocity by clicking on a wireless mouse every time they felt that they had rotated by 90°. The prehabituation perceptual response decayed exponentially with a time constant of 23.9 s. After 100 velocity steps in the same direction, this time constant was 12.9 s. The time constant after velocity steps in the opposite direction was 13.4 s, indicating that the habituation of the sensation of rotation is not direction specific. The peak velocity of the perceptual response was not affected by the habituation training. The differences between the habituation characteristics of self-motion perception and eye movements confirm that different velocity storage mechanisms mediate ocular and perceptual responses.

  20. Effects of Protein Restriction on Perceptual-Motor Development, Habituation and Learning.

    ERIC Educational Resources Information Center

    Elias, Marjorie F.

    Perceptual motor development, habituation, and learning in squirrel monkeys were studied under controlled rearing and diet history conditions to determine whether the animal's level of behavioral development was similar to well-nourished animals of his own age (agemates) or his own size (sizemates). From birth to 8 weeks of age, the animals were…

  1. Habitual sugar intake and cognitive function among middle-aged and older Puerto Ricans without diabetes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intake of added sugars, mainly fructose and sucrose, has been associated with risk factors for cognitive impairment, such as obesity, the metabolic syndrome and type 2 diabetes. The objective of this analysis was to examine whether habitual intakes of total sugars, added sugars, sugar-sweetened bev...

  2. Measurement of Habitual Physical Activity Performance in Adolescents with Cerebral Palsy: A Systematic Review

    ERIC Educational Resources Information Center

    Clanchy, Kelly M.; Tweedy, Sean M.; Boyd, Roslyn

    2011-01-01

    Aim: This systematic review compares the validity, reliability, and clinical use of habitual physical activity (HPA) performance measures in adolescents with cerebral palsy (CP). Method: Measures of HPA across Gross Motor Function Classification System (GMFCS) levels I-V for adolescents (10-18y) with CP were included if at least 60% of items…

  3. A comparative biomechanical analysis of habitually unshod and shod runners based on a foot morphological difference.

    PubMed

    Mei, Qichang; Fernandez, Justin; Fu, Weijie; Feng, Neng; Gu, Yaodong

    2015-08-01

    Running is one of the most accessible physical activities and running with and without footwear has attracted extensive attention in the past several years. In this study 18 habitually male unshod runners and 20 habitually male shod runners (all with dominant right feet) participated in a running test. A Vicon motion analysis system was used to capture the kinematics of each participant's lower limb. The in-shoe plantar pressure measurement system was employed to measure the pressure and force exerted on the pressure sensors of the insole. The function of a separate hallux in unshod runners is analyzed through the comparison of plantar pressure parameters. Owing to the different strike patterns in shod and unshod runners, peak dorsiflexion and plantarflexion angle were significantly different. Habitually shod runners exhibited a decreased foot strike angle (FSA) under unshod conditions; and the vertical average loading rate (VALR) of shod runners under unshod conditions was larger than that under shod conditions. This suggests that the foot strike pattern is more important than the shod or unshod running style and runners need to acquire the technique. It can be concluded that for habitually unshod runners the separate hallux takes part of the foot loading and reduces loading to the forefoot under shod conditions. The remaining toes of rearfoot strike (RFS) runners function similarly under unshod conditions. These morphological features of shod and unshod runners should be considered in footwear design to improve sport performance and reduce injury. PMID:25964998

  4. The Acquisition Path for Tense-Aspect: Remote Past and Habitual in Child African American English

    ERIC Educational Resources Information Center

    Green, Lisa; Roeper, Thomas

    2007-01-01

    This article considers the comprehension of tense-aspect markers remote past BIN and habitual be by 3- to 5-year-old developing African American English (AAE)-speaking children and their Southwest Louisiana Vernacular English (SwLVE)-speaking peers. Overall both groups of children associated BIN with the distant past; however, the AAE-speaking…

  5. Habituation of Bean (Phaseolus vulgaris) Cell Cultures to Quinclorac and Analysis of the Subsequent Cell Wall Modifications

    PubMed Central

    Alonso-Simón, Ana; García-Angulo, Penélope; Encina, Antonio; Acebes, José Luis; Álvarez, Jesús

    2008-01-01

    Background and Aims The herbicide quinclorac has been reported to inhibit incorporation of glucose both into cellulose and other cell wall polysaccharides. However, further work has failed to detect any apparent effect of this herbicide on the synthesis of the wall. In order to elucidate whether quinclorac elicits the inhibition of cellulose biosynthesis directly, in this study bean cell calli were habituated to grow on lethal concentrations of the herbicide and the modifications in cell wall composition due to the habituation process were analysed. Methods Fourier transform infrared spectroscopy associated with multivariate analysis, cell wall fractionation techniques, biochemical analyses and the immunolocation of different cell wall components with specific monoclonal antibodies were used to characterize the cell walls of quinclorac-habituated cells. Key Results Quinclorac-habituated cells were more irregularly shaped than non-habituated cells and they accumulated an extracellular material, which was more abundant as the level of habituation rose. Habituated cells did not show any decrease in cellulose content, but cell wall fractionation revealed that changes occurred in the distribution and post-depositional modifications of homogalacturonan and rhamnogalacturonan I during the habituation process. Therefore, since the action of quinclorac on the cell wall does not seem to be due to a direct inhibition of any cell wall component, it is suggested that the effect of quinclorac on the cell wall could be due to a side-effect of the herbicide. Conclusions Long-term modifications of the cell wall caused by the habituation of bean cell cultures to quinclorac did not resemble those of bean cells habituated to the well-known cellulose biosynthesis inhibitors dichlobenil or isoxaben. Quinclorac does not seem to act primarily as an inhibitor of cellulose biosynthesis. PMID:18408242

  6. Age-Related Cognitive Impairments in Mice with a Conditional Ablation of the Neural Cell Adhesion Molecule

    ERIC Educational Resources Information Center

    Bisaz, Reto; Boadas-Vaello, Pere; Genoux, David; Sandi, Carmen

    2013-01-01

    Most of the mechanisms involved in neural plasticity support cognition, and aging has a considerable effect on some of these processes. The neural cell adhesion molecule (NCAM) of the immunoglobulin superfamily plays a pivotal role in structural and functional plasticity and is required to modulate cognitive and emotional behaviors. However,…

  7. Habituation of the responsiveness of mesolimbic and mesocortical dopamine transmission to taste stimuli.

    PubMed

    De Luca, Maria A

    2014-01-01

    The presentation of novel, remarkable, and unpredictable tastes increases dopamine (DA) transmission in different DA terminal areas such as the nucleus accumbens (NAc) shell and core and the medial prefrontal cortex (mPFC), as estimated by in vivo microdialysis studies in rats. This effect undergoes adaptive regulation, as there is a decrease in DA responsiveness after a single pre-exposure to the same taste. This phenomenon termed habituation has been described as peculiar to NAc shell but not to NAc core and mPFC DA transmission. On this basis, it has been proposed that mPFC DA codes for generic motivational stimulus value and, together with the NAc core DA, is more consistent with a role in the expression of motivation. Conversely, NAc shell DA is specifically activated by unfamiliar or novel taste stimuli and rewards, and might serve to associate the sensory properties of the rewarding stimulus with its biological effect (Bassareo etal., 2002; Di Chiara etal., 2004). Notably, habituation of the DA response to intraoral sweet or bitter tastes is not associated with a reduction in hedonic or aversive taste reactions, thus indicating that habituation is unrelated to satiety-induced hedonic devaluation and that it is not influenced by DA alteration or depletion. This mini-review describes specific circumstances of disruption of the habituation of NAc shell DA responsiveness (De Luca etal., 2011; Bimpisidis etal., 2013). In particular, we observed an abolishment of NAc shell DA habituation to chocolate (sweet taste) by morphine sensitization and mPFC 6-hydroxy-dopamine hydrochloride (6-OHDA) lesion. Moreover, morphine sensitization was associated with the appearance of the habituation in the mPFC, and with an increased and delayed response of NAc core DA to taste in naive rats, but not in pre-exposed animals. The results here described shed light on the mechanism of the habituation phenomenon of mesolimbic and mesocortical DA transmission, and its putative role as a

  8. Spinal Plasticity following Intermittent Hypoxia: Implications for Spinal Injury

    PubMed Central

    Dale-Nagle, Erica A.; Hoffman, Michael S.; MacFarlane, Peter M.; Satriotomo, Irawan; Lovett-Barr, Mary Rachael; Vinit, Stéphane; Mitchell, Gordon S.

    2011-01-01

    Plasticity is a fundamental property of the neural system controlling breathing. One frequently studied model of respiratory plasticity is long-term facilitation of phrenic motor output (pLTF) following acute intermittent hypoxia (AIH). pLTF arises from spinal plasticity, increasing respiratory motor output through a mechanism that requires new synthesis of brain derived neurotrophic factor (BDNF), activation of its high affinity receptor, tropomyosin-related kinase B (TrkB) and extracellular-related kinase (ERK) mitogen-activated protein (MAP) kinase signaling in or near phrenic motor neurons. Since intermittent hypoxia induces spinal plasticity, we are exploring the potential to harness repetitive AIH as a means of inducing functional recovery in conditions causing respiratory insufficiency, such as cervical spinal injury. Since repetitive AIH induces phenotypic plasticity in respiratory and motor neurons, it may restore respiratory motor function in patients with incomplete spinal injury. PMID:20536940

  9. Cold habituation does not improve manual dexterity during rest and exercise in 5 °C

    NASA Astrophysics Data System (ADS)

    Muller, Matthew D.; Seo, Yongsuk; Kim, Chul-Ho; Ryan, Edward J.; Pollock, Brandon S.; Burns, Keith J.; Glickman, Ellen L.

    2014-04-01

    When exposed to a cold environment, a barehanded person experiences pain, cold sensation, and reduced manual dexterity. Both acute (e.g. exercise) and chronic (e.g. cold acclimatization or habituation) processes might lessen these negative effects. The purpose of this experiment was to determine the effect of cold habituation on physiology, perception, and manual dexterity during rest, exercise, and recovery in 5 °C. Six cold weather athletes (CWA) and eight non habituated men (NON) volunteered to participate in a repeated measures cross-over design. The protocol was conducted in 5 °C and was 90 min of resting cold exposure, 30 min of cycle ergometry exercise (50 % VO2 peak), and 60 min of seated recovery. Core and finger skin temperature, metabolic rate, Purdue Pegboard dexterity performance, hand pain, thermal sensation, and mood were quantified. Exercise-induced finger rewarming (EIFRW) was calculated for each hand. During 90 min of resting exposure to 5 °C, the CWA had a smaller reduction in finger temperature, a lower metabolic rate, less hand pain, and less negative mood. Despite this cold habituation, dexterity performance was not different between groups. In response to cycle ergometry, EIFRW was greater in CWA (~12 versus 7 °C) and occurred at lower core temperatures (37.02 versus 37.31 °C) relative to NON but dexterity was not greater during post-exercise recovery. The current data indicate that cold habituated men (i.e., CWA) do not perform better on the Purdue Pegboard during acute cold exposure. Furthermore, despite augmented EIFRW in CWA, dexterity during post-exercise recovery was similar between groups.

  10. Variation in Foot Strike Patterns during Running among Habitually Barefoot Populations

    PubMed Central

    Hatala, Kevin G.; Dingwall, Heather L.; Wunderlich, Roshna E.; Richmond, Brian G.

    2013-01-01

    Endurance running may have a long evolutionary history in the hominin clade but it was not until very recently that humans ran wearing shoes. Research on modern habitually unshod runners has suggested that they utilize a different biomechanical strategy than runners who wear shoes, namely that barefoot runners typically use a forefoot strike in order to avoid generating the high impact forces that would be experienced if they were to strike the ground with their heels first. This finding suggests that our habitually unshod ancestors may have run in a similar way. However, this research was conducted on a single population and we know little about variation in running form among habitually barefoot people, including the effects of running speed, which has been shown to affect strike patterns in shod runners. Here, we present the results of our investigation into the selection of running foot strike patterns among another modern habitually unshod group, the Daasanach of northern Kenya. Data were collected from 38 consenting adults as they ran along a trackway with a plantar pressure pad placed midway along its length. Subjects ran at self-selected endurance running and sprinting speeds. Our data support the hypothesis that a forefoot strike reduces the magnitude of impact loading, but the majority of subjects instead used a rearfoot strike at endurance running speeds. Their percentages of midfoot and forefoot strikes increased significantly with speed. These results indicate that not all habitually barefoot people prefer running with a forefoot strike, and suggest that other factors such as running speed, training level, substrate mechanical properties, running distance, and running frequency, influence the selection of foot strike patterns. PMID:23326341

  11. Review of Research: Neuroscience and the Impact of Brain Plasticity on Braille Reading

    ERIC Educational Resources Information Center

    Hannan, Cheryl Kamei

    2006-01-01

    In this systematic review of research, the author analyzes studies of neural cortical activation, brain plasticity, and braille reading. The conclusions regarding the brain's plasticity and ability to reorganize are encouraging for individuals with degenerative eye conditions or late-onset blindness because they indicate that the brain can make…

  12. Network-timing-dependent plasticity

    PubMed Central

    Delattre, Vincent; Keller, Daniel; Perich, Matthew; Markram, Henry; Muller, Eilif B.

    2015-01-01

    Bursts of activity in networks of neurons are thought to convey salient information and drive synaptic plasticity. Here we report that network bursts also exert a profound effect on Spike-Timing-Dependent Plasticity (STDP). In acute slices of juvenile rat somatosensory cortex we paired a network burst, which alone induced long-term depression (LTD), with STDP-induced long-term potentiation (LTP) and LTD. We observed that STDP-induced LTP was either unaffected, blocked or flipped into LTD by the network burst, and that STDP-induced LTD was either saturated or flipped into LTP, depending on the relative timing of the network burst with respect to spike coincidences of the STDP event. We hypothesized that network bursts flip STDP-induced LTP to LTD by depleting resources needed for LTP and therefore developed a resource-dependent STDP learning rule. In a model neural network under the influence of the proposed resource-dependent STDP rule, we found that excitatory synaptic coupling was homeostatically regulated to produce power law distributed burst amplitudes reflecting self-organized criticality, a state that ensures optimal information coding. PMID:26106298

  13. Waste plastics liquefaction technology

    SciTech Connect

    Machidori, Hideki; Ikawa, Hironori

    1996-12-31

    Plastics are now indispensable not only in industries but for daily life because of their excellent convenience. Only in Japan, about 12.25 million tons of plastics were produced in 1993. On the other hand, the production of waste plastics in the form of industrial and municipal wastes reached 7.56 million tons in the same year. A greater part of the produced waste plastics are now disposed of by incineration and landfill. The incineration would however generate detrimental substances from burned-up plastics and emit them into the exhaust gas, while the landfill would reduce rapidly the residual capacity of the final repositories. Under the circumstances, the Law for the Promotion of Sorted Collection and Recommercialization of Plastics Containers and Packages is to be enforced in 2000 in Japan. Waste plastics liquefaction technology has become high-lighted and is presupposed to employ for the treatment of waste plastics other than PET bottles in the law for the reason that relatively wide variety of waste plastics can be processed in quantity by this technology. The Kubota Corporation has made R and D efforts relating to the plastics liquefaction technology for more than 4 years, and it is now entering the stage of its commercialization.

  14. How Plastics Work

    NASA Astrophysics Data System (ADS)

    Bloomfield, Louis

    2013-03-01

    We encounter plastics every day, but despite their widespread use, amazing range of properties, and basic scientific underpinnings, most physicists--like most people--know relatively little about plastics. In contrast to hard crystalline and amorphous solids (e.g., metals, salts, ceramics, and glasses), we take plastics for granted, select them carelessly, and examine them more closely only on a need-to-know basis. By ignoring plastics until we need them, however, we risk not knowing what we don't know and using the wrong ones. To repurpose a familiar advertisement, ``there's a plastic for that.'' This talk will review some of the basic physics and science of plastics. It will examine the roles of temperature, order, intermolecular forces, entanglements, and linkages in plastics, and how those issues affect the properties of a given plastic. We'll stop along the way to recognize a few of the more familiar plastics, natural and synthetic, and explain some of their mechanical, chemical, and optical properties. The talk will conclude by explaining the remarkable properties of a plastic that has been largely misunderstood since its discovery 70 years ago: Silly Putty.

  15. Memory capacities for synaptic and structural plasticity.

    PubMed

    Knoblauch, Andreas; Palm, Günther; Sommer, Friedrich T

    2010-02-01

    Neural associative networks with plastic synapses have been proposed as computational models of brain functions and also for applications such as pattern recognition and information retrieval. To guide biological models and optimize technical applications, several definitions of memory capacity have been used to measure the efficiency of associative memory. Here we explain why the currently used performance measures bias the comparison between models and cannot serve as a theoretical benchmark. We introduce fair measures for information-theoretic capacity in associative memory that also provide a theoretical benchmark. In neural networks, two types of manipulating synapses can be discerned: synaptic plasticity, the change in strength of existing synapses, and structural plasticity, the creation and pruning of synapses. One of the new types of memory capacity we introduce permits quantifying how structural plasticity can increase the network efficiency by compressing the network structure, for example, by pruning unused synapses. Specifically, we analyze operating regimes in the Willshaw model in which structural plasticity can compress the network structure and push performance to the theoretical benchmark. The amount C of information stored in each synapse can scale with the logarithm of the network size rather than being constant, as in classical Willshaw and Hopfield nets (< or = ln 2 approximately 0.7). Further, the review contains novel technical material: a capacity analysis of the Willshaw model that rigorously controls for the level of retrieval quality, an analysis for memories with a nonconstant number of active units (where C < or = 1/e ln 2 approximately 0.53), and the analysis of the computational complexity of associative memories with and without network compression.

  16. RM-SORN: a reward-modulated self-organizing recurrent neural network.

    PubMed

    Aswolinskiy, Witali; Pipa, Gordon

    2015-01-01

    Neural plasticity plays an important role in learning and memory. Reward-modulation of plasticity offers an explanation for the ability of the brain to adapt its neural activity to achieve a rewarded goal. Here, we define a neural network model that learns through the interaction of Intrinsic Plasticity (IP) and reward-modulated Spike-Timing-Dependent Plasticity (STDP). IP enables the network to explore possible output sequences and STDP, modulated by reward, reinforces the creation of the rewarded output sequences. The model is tested on tasks for prediction, recall, non-linear computation, pattern recognition, and sequence generation. It achieves performance comparable to networks trained with supervised learning, while using simple, biologically motivated plasticity rules, and rewarding strategies. The results confirm the importance of investigating the interaction of several plasticity rules in the context of reward-modulated learning and whether reward-modulated self-organization can explain the amazing capabilities of the brain.

  17. RM-SORN: a reward-modulated self-organizing recurrent neural network

    PubMed Central

    Aswolinskiy, Witali; Pipa, Gordon

    2015-01-01

    Neural plasticity plays an important role in learning and memory. Reward-modulation of plasticity offers an explanation for the ability of the brain to adapt its neural activity to achieve a rewarded goal. Here, we define a neural network model that learns through the interaction of Intrinsic Plasticity (IP) and reward-modulated Spike-Timing-Dependent Plasticity (STDP). IP enables the network to explore possible output sequences and STDP, modulated by reward, reinforces the creation of the rewarded output sequences. The model is tested on tasks for prediction, recall, non-linear computation, pattern recognition, and sequence generation. It achieves performance comparable to networks trained with supervised learning, while using simple, biologically motivated plasticity rules, and rewarding strategies. The results confirm the importance of investigating the interaction of several plasticity rules in the context of reward-modulated learning and whether reward-modulated self-organization can explain the amazing capabilities of the brain. PMID:25852533

  18. Progesterone Regulation of Synaptic Transmission and Plasticity in Rodent Hippocampus

    ERIC Educational Resources Information Center

    Foy, Michael R.; Akopian, Garnik; Thompson, Richard F.

    2008-01-01

    Ovarian hormones influence memory formation by eliciting changes in neural activity. The effects of various concentrations of progesterone (P4) on synaptic transmission and plasticity associated with long-term potentiation (LTP) and long-term depression (LTD) were studied using in vitro hippocampal slices. Extracellular studies show that the…

  19. Introduction to spiking neural networks: Information processing, learning and applications.

    PubMed

    Ponulak, Filip; Kasinski, Andrzej

    2011-01-01

    The concept that neural information is encoded in the firing rate of neurons has been the dominant paradigm in neurobiology for many years. This paradigm has also been adopted by the theory of artificial neural networks. Recent physiological experiments demonstrate, however, that in many parts of the nervous system, neural code is founded on the timing of individual action potentials. This finding has given rise to the emergence of a new class of neural models, called spiking neural networks. In this paper we summarize basic properties of spiking neurons and spiking networks. Our focus is, specifically, on models of spike-based information coding, synaptic plasticity and learning. We also survey real-life applications of spiking models. The paper is meant to be an introduction to spiking neural networks for scientists from various disciplines interested in spike-based neural processing.

  20. Translational Approach to Behavioral Learning: Lessons from Cerebellar Plasticity

    PubMed Central

    Cheron, Guy; Dan, Bernard; Márquez-Ruiz, Javier

    2013-01-01

    The role of cerebellar plasticity has been increasingly recognized in learning. The privileged relationship between the cerebellum and the inferior olive offers an ideal circuit for attempting to integrate the numerous evidences of neuronal plasticity into a translational perspective. The high learning capacity of the Purkinje cells specifically controlled by the climbing fiber represents a major element within the feed-forward and feedback loops of the cerebellar cortex. Reciprocally connected with the basal ganglia and multimodal cerebral domains, this cerebellar network may realize fundamental functions in a wide range of behaviors. This review will outline the current understanding of three main experimental paradigms largely used for revealing cerebellar functions in behavioral learning: (1) the vestibuloocular reflex and smooth pursuit control, (2) the eyeblink conditioning, and (3) the sensory envelope plasticity. For each of these experimental conditions, we have critically revisited the chain of causalities linking together neural circuits, neural signals, and plasticity mechanisms, giving preference to behaving or alert animal physiology. Namely, recent experimental approaches mixing neural units and local field potentials recordings have demonstrated a spike timing dependent plasticity by which the cerebellum remains at a strategic crossroad for deciphering fundamental and translational mechanisms from cellular to network levels. PMID:24319600