Challenging aspects of contemporary cochlear implant electrode array design.

PubMed

Mistrík, Pavel; Jolly, Claude; Sieber, Daniel; Hochmair, Ingeborg

2017-12-01

A design comparison of current perimodiolar and lateral wall electrode arrays of the cochlear implant (CI) is provided. The focus is on functional features such as acoustic frequency coverage and tonotopic mapping, battery consumption and dynamic range. A traumacity of their insertion is also evaluated. Review of up-to-date literature. Perimodiolar electrode arrays are positioned in the basal turn of the cochlea near the modiolus. They are designed to initiate the action potential in the proximity to the neural soma located in spiral ganglion. On the other hand, lateral wall electrode arrays can be inserted deeper inside the cochlea, as they are located along the lateral wall and such insertion trajectory is less traumatic. This class of arrays targets primarily surviving neural peripheral processes. Due to their larger insertion depth, lateral wall arrays can deliver lower acoustic frequencies in manner better corresponding to cochlear tonotopicity. In fact, spiral ganglion sections containing auditory nerve fibres tuned to low acoustic frequencies are located deeper than 1 and half turn inside the cochlea. For this reason, a significant frequency mismatch might be occurring for apical electrodes in perimodiolar arrays, detrimental to speech perception. Tonal languages such as Mandarin might be therefore better treated with lateral wall arrays. On the other hand, closer proximity to target tissue results in lower psychophysical threshold levels for perimodiolar arrays. However, the maximal comfort level is also lower, paradoxically resulting in narrower dynamic range than that of lateral wall arrays. Battery consumption is comparable for both types of arrays. Lateral wall arrays are less likely to cause trauma to cochlear structures. As the current trend in cochlear implantation is the maximal protection of residual acoustic hearing, the lateral wall arrays seem more suitable for hearing preservation CI surgeries. Future development could focus on combining the advantages of both types: perimodiolar location in the basal turn extended to lateral wall location for higher turn locations.

Autoradiographic labelling of P2 purinoceptors in the guinea-pig cochlea.

PubMed

Mockett, B G; Bo, X; Housley, G D; Thorne, P R; Burnstock, G

1995-04-01

Two different radioligands were used to identify extracellular ATP binding sites specific to P2 purinoceptors in guinea-pig cochlear tissue. Deoxyadenosine 5'-(alpha-[35S]thio)triphosphate ([35S]dATP alpha S; 10 nM) provided a high activity probe for the P2y purinoceptor subtype on the basis of selective block by 2-methylthio-ATP (2MeSATP; 100 microM). [3H]alpha, beta-methylene-ATP (10 nM), a high affinity probe for a P2x purinoceptor subtype was selectively blocked by inclusion of the related compound beta, gamma-methylene-ATP (100 microM). Both probes labelled the organ of Corti, stria vascularis and spiral prominence regions. The P2x purinoceptor probe also bound to lateral wall tissue below the spiral prominence and insertion point of the basilar membrane within the scala tympani compartment, a region which failed to show significant binding using [35S]dATP alpha S. Frozen sections of whole cochlea permitted analysis of radioligand binding to the cell body region (spiral ganglion in Rosenthal's canal) of the primary auditory afferents and the auditory nerve itself, which lies within the central region of the modiolus of the cochlea. Both these regions exhibited 2MeSATP blockable [35S]dATP alpha S binding whereas specific [3H]alpha, beta-methylene-ATP binding was absent from spiral ganglion and minimal in the auditory nerve region. These results demonstrate a mixed P2 purinoceptor distribution in cochlear tissues and suggest that complex purine-mediated neurohumoral mechanisms may influence cochlear function at a number of sites.

Impedance measurements of the human cochlear partition

NASA Astrophysics Data System (ADS)

Raufer, Stefan; Nakajima, Hideko H.

2018-05-01

The cochlea is a mechanical frequency analyzer, owing its characteristics to the impedance of the cochlear partition. In humans, the impedance of the partition has not been measured directly, and estimates of the stiffness (a principal component of the impedance) are based on loose assumptions. In this study, we examine not only the stiffness of the basilar membrane (BM), but also the osseous spiral lamina (OSL), which, in human, vibrates substantially. We hypothesize that the OSL contributes significantly to the volume stiffness of the cochlear partition (CP). We measured velocities of the BM and OSL at different radial locations 1 mm from the base of the cochlea in a fresh human cadaveric specimen. Simultaneously, we measured intracochlear pressures on the other side of the partition, in scala vestibuli. With the velocity and pressure measurements we can estimate the specific acoustic impedance of the BM and OSL (Z = p/v). At frequencies well below the resonant frequency, the stiffness of these structures can be extracted by multiplying the impedance by the radian frequency. The specific acoustic stiffness was found to be 1.2 GPa/m on the BM, 6 GPa/m at the juncture where the BM attaches to the OSL, and 10 GPa/m at the midpoint of the OSL. A beam model, appropriate to model the radial motion of the BM in guinea pig or gerbil, cannot describe the displacement of the human CP in the base. Instead, we find that the OSL is hinged near the modiolus and vibrates significantly near the connection to the more compliant BM, contributing greatly the volume compliance of the CP.

Electrophysiological evidence for altered visual, but not auditory, selective attention in adolescent cochlear implant users.

PubMed

Harris, Jill; Kamke, Marc R

2014-11-01

Selective attention fundamentally alters sensory perception, but little is known about the functioning of attention in individuals who use a cochlear implant. This study aimed to investigate visual and auditory attention in adolescent cochlear implant users. Event related potentials were used to investigate the influence of attention on visual and auditory evoked potentials in six cochlear implant users and age-matched normally-hearing children. Participants were presented with streams of alternating visual and auditory stimuli in an oddball paradigm: each modality contained frequently presented 'standard' and infrequent 'deviant' stimuli. Across different blocks attention was directed to either the visual or auditory modality. For the visual stimuli attention boosted the early N1 potential, but this effect was larger for cochlear implant users. Attention was also associated with a later P3 component for the visual deviant stimulus, but there was no difference between groups in the later attention effects. For the auditory stimuli, attention was associated with a decrease in N1 latency as well as a robust P3 for the deviant tone. Importantly, there was no difference between groups in these auditory attention effects. The results suggest that basic mechanisms of auditory attention are largely normal in children who are proficient cochlear implant users, but that visual attention may be altered. Ultimately, a better understanding of how selective attention influences sensory perception in cochlear implant users will be important for optimising habilitation strategies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Visualization of spiral ganglion neurites within the scala tympani with a cochlear implant in situ

PubMed Central

Chikar, Jennifer A.; Batts, Shelley A.; Pfingst, Bryan E.; Raphael, Yehoash

2009-01-01

Current cochlear histology methods do not allow in situ processing of cochlear implants. The metal components of the implant preclude standard embedding and mid-modiolar sectioning, and whole mounts do not have the spatial resolution needed to view the implant within the scala tympani. One focus of recent auditory research is the regeneration of structures within the cochlea, particularly the ganglion cells and their processes, and there are multiple potential benefits to cochlear implant users from this work. To facilitate experimental investigations of auditory nerve regeneration performed in conjunction with cochlear implantation, it is critical to visualize the cochlear tissue and the implant together to determine if the nerve has made contact with the implant. This paper presents a novel histological technique that enables simultaneous visualization of the in situ cochlear implant and neurofilament – labeled nerve processes within the scala tympani, and the spatial relationship between them. PMID:19428528

Visualization of spiral ganglion neurites within the scala tympani with a cochlear implant in situ.

PubMed

Chikar, Jennifer A; Batts, Shelley A; Pfingst, Bryan E; Raphael, Yehoash

2009-05-15

Current cochlear histology methods do not allow in situ processing of cochlear implants. The metal components of the implant preclude standard embedding and mid-modiolar sectioning, and whole mounts do not have the spatial resolution needed to view the implant within the scala tympani. One focus of recent auditory research is the regeneration of structures within the cochlea, particularly the ganglion cells and their processes, and there are multiple potential benefits to cochlear implant users from this work. To facilitate experimental investigations of auditory nerve regeneration performed in conjunction with cochlear implantation, it is critical to visualize the cochlear tissue and the implant together to determine if the nerve has made contact with the implant. This paper presents a novel histological technique that enables simultaneous visualization of the in situ cochlear implant and neurofilament-labeled nerve processes within the scala tympani, and the spatial relationship between them.

The consequences of neural degeneration regarding optimal cochlear implant position in scala tympani: a model approach.

PubMed

Briaire, Jeroen J; Frijns, Johan H M

2006-04-01

Cochlear implant research endeavors to optimize the spatial selectivity, threshold and dynamic range with the objective of improving the speech perception performance of the implant user. One of the ways to achieve some of these goals is by electrode design. New cochlear implant electrode designs strive to bring the electrode contacts into close proximity to the nerve fibers in the modiolus: this is done by placing the contacts on the medial side of the array and positioning the implant against the medial wall of scala tympani. The question remains whether this is the optimal position for a cochlea with intact neural fibers and, if so, whether it is also true for a cochlea with degenerated neural fibers. In this study a computational model of the implanted human cochlea is used to investigate the optimal position of the array with respect to threshold, dynamic range and spatial selectivity for a cochlea with intact nerve fibers and for degenerated nerve fibers. In addition, the model is used to evaluate the predictive value of eCAP measurements for obtaining peri-operative information on the neural status. The model predicts improved threshold, dynamic range and spatial selectivity for the peri-modiolar position at the basal end of the cochlea, with minimal influence of neural degeneration. At the apical end of the array (1.5 cochlear turns), the dynamic range and the spatial selectivity are limited due to the occurrence of cross-turn stimulation, with the exception of the condition without neural degeneration and with the electrode array along the lateral wall of scala tympani. The eCAP simulations indicate that a large P(0) peak occurs before the N(1)P(1) complex when the fibers are not degenerated. The absence of this peak might be used as an indicator for neural degeneration.

Visualization and contractile activity of cochlear pericytes in the capillaries of the spiral ligament.

PubMed

Dai, Min; Nuttall, Alfred; Yang, Yue; Shi, Xiaorui

2009-08-01

Pericytes, mural cells located on microvessels, are considered to play an important role in the formation of the vasculature and the regulation of local blood flow in some organs. Little is known about the physiology of cochlear pericytes. In order to investigate the function of cochlear pericytes, we developed a method to visualize cochlear pericytes using diaminofluorescein-2 diacetate (DAF-2DA) and intravital fluorescence microscopy. This method can permit the study of the effect of vasoactive agents on pericytes under the in vivo and normal physiological condition. The specificity of the labeling method was verified by the immunofluorescence labeling of pericyte maker proteins such as desmin, neural proteoglycan (NG2), and thymocyte differentiation antigen 1 (Thy-1). Superfused K(+) and Ca(2+) to the cochlear lateral wall resulted in localized constriction of capillaries at pericyte locations both in vivo and in vitro, while there was no obvious change in cochlear capillary diameters with application of the adrenergic neurotransmitter noradrenaline. The method could be an effective way to visualize cochlear pericytes and microvessels and study lateral wall vascular physiology. Moreover, we demonstrate for the first time that cochlear pericytes have contractility, which may be important for regulation of cochlear blood flow.

Buried Alive: The Behavioural Response of the Mussels, Modiolus modiolus and Mytilus edulis to Sudden Burial by Sediment

PubMed Central

Hutchison, Zoë L.; Hendrick, Vicki J.; Burrows, Michael T.; Wilson, Ben; Last, Kim S.

2016-01-01

Sedimentation in the sea occurs through natural processes, such as wave and tidal action, which can be exacerbated during storms and floods. Changes in terrestrial land use, marine aggregate extraction, dredging, drilling and mining are known to result in substantial sediment deposition. Research suggests that deposition will also occur due to the modern development of marine renewable energy. The response to individual burial under three depths of sediment, three sediment fractions and five burial durations was investigated in two mussel species, Modiolus modiolus and Mytilus edulis in specialist mesocosms. Both mussel species showed substantial mortality, which increased with duration of burial and burial by finer sediment fractions. M. modiolus was better able to survive short periods of burial than M. edulis, but at longer durations mortality was more pronounced. No mortality was observed in M. modiolus in burial durations of eight days or less but by 16 days of burial, over 50% cumulative mortality occurred. Under variable temperature regimes, M. edulis mortality increased from 20% at 8°C to over 60% at 14.5 and 20°C. Only M. edulis was able to emerge from burial, facilitated by increased byssus production, laid mostly on vertical surfaces but also on sediment particles. Emergence was higher from coarse sediment and shallow burials. Byssus production in M. edulis was not related to the condition index of the mussels. Results suggest that even marginal burial would result in mortality and be more pronounced in warm summer periods. Our results suggest that in the event of burial, adult M. modiolus would not be able to emerge from burial unless local hydrodynamics assist, whereas a small proportion of M. edulis may regain contact with the sediment water interface. The physiological stress resulting in mortality, contribution of local hydrodynamics to survival and other ecological pressures such as mussels existing in aggregations, are discussed. PMID:26982582

Contingent capture of involuntary visual spatial attention does not differ between normally hearing children and proficient cochlear implant users.

PubMed

Kamke, Marc R; Van Luyn, Jeanette; Constantinescu, Gabriella; Harris, Jill

2014-01-01

Evidence suggests that deafness-induced changes in visual perception, cognition and attention may compensate for a hearing loss. Such alterations, however, may also negatively influence adaptation to a cochlear implant. This study investigated whether involuntary attentional capture by salient visual stimuli is altered in children who use a cochlear implant. Thirteen experienced implant users (aged 8-16 years) and age-matched normally hearing children were presented with a rapid sequence of simultaneous visual and auditory events. Participants were tasked with detecting numbers presented in a specified color and identifying a change in the tonal frequency whilst ignoring irrelevant visual distractors. Compared to visual distractors that did not possess the target-defining characteristic, target-colored distractors were associated with a decrement in visual performance (response time and accuracy), demonstrating a contingent capture of involuntary attention. Visual distractors did not, however, impair auditory task performance. Importantly, detection performance for the visual and auditory targets did not differ between the groups. These results suggest that proficient cochlear implant users demonstrate normal capture of visuospatial attention by stimuli that match top-down control settings.

Degradation of labial information modifies audiovisual speech perception in cochlear-implanted children.

PubMed

Huyse, Aurélie; Berthommier, Frédéric; Leybaert, Jacqueline

2013-01-01

The aim of the present study was to examine audiovisual speech integration in cochlear-implanted children and in normally hearing children exposed to degraded auditory stimuli. Previous studies have shown that speech perception in cochlear-implanted users is biased toward the visual modality when audition and vision provide conflicting information. Our main question was whether an experimentally designed degradation of the visual speech cue would increase the importance of audition in the response pattern. The impact of auditory proficiency was also investigated. A group of 31 children with cochlear implants and a group of 31 normally hearing children matched for chronological age were recruited. All children with cochlear implants had profound congenital deafness and had used their implants for at least 2 years. Participants had to perform an /aCa/ consonant-identification task in which stimuli were presented randomly in three conditions: auditory only, visual only, and audiovisual (congruent and incongruent McGurk stimuli). In half of the experiment, the visual speech cue was normal; in the other half (visual reduction) a degraded visual signal was presented, aimed at preventing lipreading of good quality. The normally hearing children received a spectrally reduced speech signal (simulating the input delivered by the cochlear implant). First, performance in visual-only and in congruent audiovisual modalities were decreased, showing that the visual reduction technique used here was efficient at degrading lipreading. Second, in the incongruent audiovisual trials, visual reduction led to a major increase in the number of auditory based responses in both groups. Differences between proficient and nonproficient children were found in both groups, with nonproficient children's responses being more visual and less auditory than those of proficient children. Further analysis revealed that differences between visually clear and visually reduced conditions and between groups were not only because of differences in unisensory perception but also because of differences in the process of audiovisual integration per se. Visual reduction led to an increase in the weight of audition, even in cochlear-implanted children, whose perception is generally dominated by vision. This result suggests that the natural bias in favor of vision is not immutable. Audiovisual speech integration partly depends on the experimental situation, which modulates the informational content of the sensory channels and the weight that is awarded to each of them. Consequently, participants, whether deaf with cochlear implants or having normal hearing, not only base their perception on the most reliable modality but also award it an additional weight.

SEASONAL VARIABILTIY LIPIDS, LIPID CLASSES AND PCBS IN INDIGENOUS POPULATIONS OF RIBBED MUSSELS, MODIOLUS DEMISSUS

EPA Science Inventory

Two indigenous ribbed mussel (Modiolus demissus) populations were sampled approximately every four weeks during 1997 to investigate the seasonal variability of total lipids, lipid classes, and polychlorinated biphenyl (PCB) concentrations. One population was located in a highly c...

Visual activity predicts auditory recovery from deafness after adult cochlear implantation.

PubMed

Strelnikov, Kuzma; Rouger, Julien; Demonet, Jean-François; Lagleyre, Sebastien; Fraysse, Bernard; Deguine, Olivier; Barone, Pascal

2013-12-01

Modern cochlear implantation technologies allow deaf patients to understand auditory speech; however, the implants deliver only a coarse auditory input and patients must use long-term adaptive processes to achieve coherent percepts. In adults with post-lingual deafness, the high progress of speech recovery is observed during the first year after cochlear implantation, but there is a large range of variability in the level of cochlear implant outcomes and the temporal evolution of recovery. It has been proposed that when profoundly deaf subjects receive a cochlear implant, the visual cross-modal reorganization of the brain is deleterious for auditory speech recovery. We tested this hypothesis in post-lingually deaf adults by analysing whether brain activity shortly after implantation correlated with the level of auditory recovery 6 months later. Based on brain activity induced by a speech-processing task, we found strong positive correlations in areas outside the auditory cortex. The highest positive correlations were found in the occipital cortex involved in visual processing, as well as in the posterior-temporal cortex known for audio-visual integration. The other area, which positively correlated with auditory speech recovery, was localized in the left inferior frontal area known for speech processing. Our results demonstrate that the visual modality's functional level is related to the proficiency level of auditory recovery. Based on the positive correlation of visual activity with auditory speech recovery, we suggest that visual modality may facilitate the perception of the word's auditory counterpart in communicative situations. The link demonstrated between visual activity and auditory speech perception indicates that visuoauditory synergy is crucial for cross-modal plasticity and fostering speech-comprehension recovery in adult cochlear-implanted deaf patients.

Relational Learning in Children with Deafness and Cochlear Implants

ERIC Educational Resources Information Center

Almeida-Verdu, Ana Claudia; Huziwara, Edson M.; de Souza, Deisy G.; de Rose, Julio C.; Bevilacqua, Maria Cecilia; Lopes, Jair, Jr.; Alves, Cristiane O.; McIlvane, William J.

2008-01-01

This four-experiment series sought to evaluate the potential of children with neurosensory deafness and cochlear implants to exhibit auditory-visual and visual-visual stimulus equivalence relations within a matching-to-sample format. Twelve children who became deaf prior to acquiring language (prelingual) and four who became deaf afterwards…

Clinical investigation of the Nucleus Slim Modiolar Electrode.

PubMed

Aschendorff, Antje; Briggs, Robert; Brademann, Goetz; Helbig, Silke; Hornung, Joachim; Lenarz, Thomas; Marx, Mathieu; Ramos, Angel; Stöver, Timo; Escudé, Bernard; James, Chris J

2017-01-01

The Nucleus CI532 cochlear implant incorporates a new precurved electrode array, i.e., the Slim Modiolar electrode (SME), which is designed to bring electrode contacts close to the medial wall of the cochlea while avoiding trauma due to scalar dislocation or contact with the lateral wall during insertion. The primary aim of this prospective study was to determine the final position of the electrode array in clinical cases as evaluated using flat-panel volume computed tomography. Forty-five adult candidates for unilateral cochlear implantation were recruited from 8 centers. Eleven surgeons attended a temporal bone workshop and received further training with a transparent plastic cochlear model just prior to the first surgery. Feedback on the surgical approach and use of the SME was collected via a questionnaire for each case. Computed tomography of the temporal bone was performed postoperatively using flat-panel digital volume tomography or cone beam systems. The primary measure was the final scalar position of the SME (completely in scala tympani or not). Secondly, medial-lateral position and insertion depth were evaluated. Forty-four subjects received a CI532. The SME was located completely in scala tympani for all subjects. Pure round window (44% of the cases), extended round window (22%), and inferior and/or anterior cochleostomy (34%) approaches were successful across surgeons and cases. The SME was generally positioned close to the modiolus. Overinsertion of the array past the first marker tended to push the basal contacts towards the lateral wall and served only to increase the insertion depth of the first electrode contact without increasing the insertion depth of the most apical electrode. Complications were limited to tip fold-overs encountered in 2 subjects; both were attributed to surgical error, with both reimplanted successfully. The new Nucleus CI532 cochlear implant with SME achieved the design goal of producing little or no trauma as indicated by consistent scala tympani placement. Surgeons should be carefully trained to use the new deployment method such that tip fold-overs and over insertion may be avoided. © 2017 S. Karger AG, Basel.

The new mid-scala electrode array: a radiologic and histologic study in human temporal bones.

PubMed

Hassepass, Frederike; Bulla, Stefan; Maier, Wolfgang; Laszig, Roland; Arndt, Susan; Beck, Rainer; Traser, Lousia; Aschendorff, Antje

2014-09-01

To analyze the quality of insertion of the newly developed midscala (MS) electrode, which targets a midscalar electrode position to reduce the risk of trauma to the lateral wall and the modiolus. Modern cochlear implant surgery aims for a safe intracochlear placement of electrode arrays with an ongoing debate regarding cochleostomy or round window (RW) insertion and the use of lateral wall or perimodiolar electrode placement. Intracochlear trauma after insertion of different electrodes depends on insertion mode and electrode design and may result in trauma to the delicate structures of the cochlear. We performed a temporal bone (TB) trial with insertion of the MS electrode in n = 20 TB's after a mastoidectomy and posterior tympanotomy. Insertion was performed either via the RW or a cochleostomy. Electrode positioning, length of insertion, and angle of insertion were analyzed with rotational tomography (RT). TBs were histologically analyzed. Results of RT and histology were compared. Scala tympani (ST) insertion could be accomplished reliably by both RW and via a cochleostomy approach. In 20 TBs, 1 scala vestibuli insertion, 1 incomplete (ST), and 1 elevation of basilar membrane were depicted. No trauma was found in 94.7% of all ST insertions. RT allowed determination of the intracochlear electrode position, which was specified by histologic sectioning. The new MS electrode seems to fulfill reliable atraumatic intracochlear placement via RW and cochleostomy approaches. RT is available for evaluation of intracochlear electrode position, serving as a potential quality control instrument in human implantation.

Direct Reprogramming of Spiral Ganglion Non-neuronal Cells into Neurons: Toward Ameliorating Sensorineural Hearing Loss by Gene Therapy

PubMed Central

Noda, Teppei; Meas, Steven J.; Nogami, Jumpei; Amemiya, Yutaka; Uchi, Ryutaro; Ohkawa, Yasuyuki; Nishimura, Koji; Dabdoub, Alain

2018-01-01

Primary auditory neurons (PANs) play a critical role in hearing by transmitting sound information from the inner ear to the brain. Their progressive degeneration is associated with excessive noise, disease and aging. The loss of PANs leads to permanent hearing impairment since they are incapable of regenerating. Spiral ganglion non-neuronal cells (SGNNCs), comprised mainly of glia, are resident within the modiolus and continue to survive after PAN loss. These attributes make SGNNCs an excellent target for replacing damaged PANs through cellular reprogramming. We used the neurogenic pioneer transcription factor Ascl1 and the auditory neuron differentiation factor NeuroD1 to reprogram SGNNCs into induced neurons (iNs). The overexpression of both Ascl1 and NeuroD1 in vitro generated iNs at high efficiency. Transcriptome analyses revealed that iNs displayed a transcriptome profile resembling that of endogenous PANs, including expression of several key markers of neuronal identity: Tubb3, Map2, Prph, Snap25, and Prox1. Pathway analyses indicated that essential pathways in neuronal growth and maturation were activated in cells upon neuronal induction. Furthermore, iNs extended projections toward cochlear hair cells and cochlear nucleus neurons when cultured with each respective tissue. Taken together, our study demonstrates that PAN-like neurons can be generated from endogenous SGNNCs. This work suggests that gene therapy can be a viable strategy to treat sensorineural hearing loss caused by degeneration of PANs. PMID:29492404

Audition and Visual Attention: The Developmental Trajectory in Deaf and Hearing Populations.

ERIC Educational Resources Information Center

Smith, Linda B.; Quittner, Alexandra L.; Osberger, Mary Joe; Miyamoto, Richard

1998-01-01

Two experiments examined visual attention in 5- to 13-year olds who were hearing or deaf with or without cochlear implants. Findings indicated that visual selective attention changes occurred around 8 years for all groups, with deaf children without cochlear implants performing less well than others. Differences between deaf children with and…

In vivo imaging of mammalian cochlear blood flow using fluorescence microendoscopy.

PubMed

Monfared, Ashkan; Blevins, Nikolas H; Cheung, Eunice L M; Jung, Juergen C; Popelka, Gerald; Schnitzer, Mark J

2006-02-01

We sought to develop techniques for visualizing cochlear blood flow in live mammalian subjects using fluorescence microendoscopy. Inner ear microcirculation appears to be intimately involved in cochlear function. Blood velocity measurements suggest that intense sounds can alter cochlear blood flow. Disruption of cochlear blood flow may be a significant cause of hearing impairment, including sudden sensorineural hearing loss. However, inability to image cochlear blood flow in a nondestructive manner has limited investigation of the role of inner ear microcirculation in hearing function. Present techniques for imaging cochlear microcirculation using intravital light microscopy involve extensive perturbations to cochlear structure, precluding application in human patients. The few previous endoscopy studies of the cochlea have suffered from optical resolution insufficient for visualizing cochlear microvasculature. Fluorescence microendoscopy is an emerging minimally invasive imaging modality that provides micron-scale resolution in tissues inaccessible to light microscopy. In this article, we describe the use of fluorescence microendoscopy in live guinea pigs to image capillary blood flow and movements of individual red blood cells within the basal turn of the cochlea. We anesthetized eight adult guinea pigs and accessed the inner ear through the mastoid bulla. After intravenous injection of fluorescein dye, we made a limited cochleostomy and introduced a compound doublet gradient refractive index endoscope probe 1 mm in diameter into the inner ear. We then imaged cochlear blood flow within individual vessels in an epifluorescence configuration using one-photon fluorescence microendoscopy. We observed single red blood cells passing through individual capillaries in several cochlear structures, including the round window membrane, spiral ligament, osseous spiral lamina, and basilar membrane. Blood flow velocities within inner ear capillaries varied widely, with observed speeds reaching up to approximately 500 microm/s. Fluorescence microendoscopy permits visualization of cochlear microcirculation with micron-scale optical resolution and determination of blood flow velocities through analysis of video sequences.

Assessing speech perception in children with cochlear implants using a modified hybrid visual habituation procedure.

PubMed

Core, Cynthia; Brown, Janean W; Larsen, Michael D; Mahshie, James

2014-01-01

The objectives of this research were to determine whether an adapted version of a Hybrid Visual Habituation procedure could be used to assess speech perception of phonetic and prosodic features of speech (vowel height, lexical stress, and intonation) in individual pre-school-age children who use cochlear implants. Nine children ranging in age from 3;4 to 5;5 participated in this study. Children were prelingually deaf and used cochlear implants and had no other known disabilities. Children received two speech feature tests using an adaptation of a Hybrid Visual Habituation procedure. Seven of the nine children demonstrated perception of at least one speech feature using this procedure using results from a Bayesian linear regression analysis. At least one child demonstrated perception of each speech feature using this assessment procedure. An adapted version of the Hybrid Visual Habituation Procedure with an appropriate statistical analysis provides a way to assess phonetic and prosodicaspects of speech in pre-school-age children who use cochlear implants.

Anatomy of a Natural Composite Material

DTIC Science & Technology

1989-11-01

from the vitellaria of the liver fluke, Fasciola hepatica. Biochemistry 28, 6104-6110. 2. Waite, J.H., Hansen, D.C., & Little, K.T. (1989) The glue...certainly belong to distinct genera and inhabit distinct ecological niches. Adhesive protein sequences from two non-molluscan species, Fasciola hepatica...choros), Gd (Geukensia demissa), Fh ( Fasciola hepatica), Me (Mytilus edulis), Mg (Mytella guyanensis), Mms (Modiolus modiolus squamosus), Pc

Experiments on Auditory-Visual Perception of Sentences by Users of Unilateral, Bimodal, and Bilateral Cochlear Implants

ERIC Educational Resources Information Center

Dorman, Michael F.; Liss, Julie; Wang, Shuai; Berisha, Visar; Ludwig, Cimarron; Natale, Sarah Cook

2016-01-01

Purpose: Five experiments probed auditory-visual (AV) understanding of sentences by users of cochlear implants (CIs). Method: Sentence material was presented in auditory (A), visual (V), and AV test conditions to listeners with normal hearing and CI users. Results: (a) Most CI users report that most of the time, they have access to both A and V…

The contribution of visual areas to speech comprehension: a PET study in cochlear implants patients and normal-hearing subjects.

PubMed

Giraud, Anne Lise; Truy, Eric

2002-01-01

Early visual cortex can be recruited by meaningful sounds in the absence of visual information. This occurs in particular in cochlear implant (CI) patients whose dependency on visual cues in speech comprehension is increased. Such cross-modal interaction mirrors the response of early auditory cortex to mouth movements (speech reading) and may reflect the natural expectancy of the visual counterpart of sounds, lip movements. Here we pursue the hypothesis that visual activations occur specifically in response to meaningful sounds. We performed PET in both CI patients and controls, while subjects listened either to their native language or to a completely unknown language. A recruitment of early visual cortex, the left posterior inferior temporal gyrus (ITG) and the left superior parietal cortex was observed in both groups. While no further activation occurred in the group of normal-hearing subjects, CI patients additionally recruited the right perirhinal/fusiform and mid-fusiform, the right temporo-occipito-parietal (TOP) junction and the left inferior prefrontal cortex (LIPF, Broca's area). This study confirms a participation of visual cortical areas in semantic processing of speech sounds. Observation of early visual activation in normal-hearing subjects shows that auditory-to-visual cross-modal effects can also be recruited under natural hearing conditions. In cochlear implant patients, speech activates the mid-fusiform gyrus in the vicinity of the so-called face area. This suggests that specific cross-modal interaction involving advanced stages in the visual processing hierarchy develops after cochlear implantation and may be the correlate of increased usage of lip-reading.

Protection alone may not promote natural recovery of biogenic habitats of high biodiversity damaged by mobile fishing gears.

PubMed

Fariñas-Franco, Jose M; Allcock, A Louise; Roberts, Dai

2018-04-01

The horse mussel Modiolus modiolus (L.) is a large marine bivalve that aggregates to create complex habitats of high biodiversity. As a keystone species, M. modiolus is of great importance for the functioning of marine benthic ecosystems, forming biogenic habitats used to designate Marine Protected Areas (MPAs). The present study investigates the condition of M. modiolus beds historically subjected to intense scallop fishing using mobile fishing gears. The study, conducted seven years after the introduction of legislation banning all forms of fishing, aimed to establish whether natural habitat recovery occurs after protection measures are put in place. Lower biodiversity and up to 80% decline in densities of M. modiolus were recorded across the current distributional range of the species in Strangford Lough, Northern Ireland. The decline in biodiversity in most areas surveyed was consistent with that observed in biogenic reefs impacted by mobile fishing gears elsewhere. Epifauna, including sponges, hydroids and tunicates, experienced the most substantial decline in biodiversity, with up to 64% fewer taxa recorded in 2010 compared with 2003. Higher variability in community composition and a shift towards faunal assemblages dominated by opportunistic infaunal species typical of softer substrata were also detected. Based on these observations we suggest that, for biogenic habitats, the designation of MPAs and the introduction of fishing bans alone may not be sufficient to reverse or halt the negative effects caused by past anthropogenic impacts. Direct intervention, including habitat restoration based on translocation of native keystone species, should be considered as part of management strategies for MPAs which host similar biogenic reef habitats where condition and natural recovery have been compromised. Copyright © 2018 Elsevier Ltd. All rights reserved.

The substantial first impact of bottom fishing on rare biodiversity hotspots: a dilemma for evidence-based conservation.

PubMed

Cook, Robert; Fariñas-Franco, Jose M; Gell, Fiona R; Holt, Rohan H F; Holt, Terry; Lindenbaum, Charles; Porter, Joanne S; Seed, Ray; Skates, Lucie R; Stringell, Thomas B; Sanderson, William G

2013-01-01

This study describes the impact of the first passage of two types of bottom-towed fishing gear on rare protected shellfish-reefs formed by the horse mussel Modiolus modiolus (L.). One of the study sites was trawled and the other was scallop-dredged. Divers collected HD video imagery of epifauna from quadrats at the two study sites and directed infaunal samples from one site. The total number of epifaunal organisms was significantly reduced following a single pass of a trawl (90%) or scallop dredge (59%), as was the diversity of the associated community and the total number of M. modiolus at the trawled site. At both sites declines in anthozoans, hydrozoans, bivalves, echinoderms and ascidians accounted for most of the change. A year later, no recovery was evident at the trawled site and significantly fewer infaunal taxa (polychaetes, malacostracans, bivalves and ophuroids) were recorded in the trawl track. The severity of the two types of impact reflected the undisturbed status of the habitats compared to previous studies. As a 'priority habitat' the nature of the impacts described on M. modiolus communities are important to the development of conservation management policy and indicators of condition in Marine Protected Areas (EU Habitats Directive) as well as indicators of 'Good Environmental Status' under the European Union Marine Strategy Framework Directive. Conservation managers are under pressure to support decisions with good quality evidence. Elsewhere, indirect studies have shown declines of M. modiolus biogenic communities in fishing grounds. However, given the protected status of the rare habitat, premeditated demonstration of direct impact is unethical or illegal in Marine Protected Areas. This study therefore provides a unique opportunity to investigate the impact from fishing gear whilst at the same time reflecting on the dilemma of evidence-based conservation management.

Cued Speech for Enhancing Speech Perception and First Language Development of Children With Cochlear Implants

PubMed Central

Leybaert, Jacqueline; LaSasso, Carol J.

2010-01-01

Nearly 300 million people worldwide have moderate to profound hearing loss. Hearing impairment, if not adequately managed, has strong socioeconomic and affective impact on individuals. Cochlear implants have become the most effective vehicle for helping profoundly deaf children and adults to understand spoken language, to be sensitive to environmental sounds, and, to some extent, to listen to music. The auditory information delivered by the cochlear implant remains non-optimal for speech perception because it delivers a spectrally degraded signal and lacks some of the fine temporal acoustic structure. In this article, we discuss research revealing the multimodal nature of speech perception in normally-hearing individuals, with important inter-subject variability in the weighting of auditory or visual information. We also discuss how audio-visual training, via Cued Speech, can improve speech perception in cochlear implantees, particularly in noisy contexts. Cued Speech is a system that makes use of visual information from speechreading combined with hand shapes positioned in different places around the face in order to deliver completely unambiguous information about the syllables and the phonemes of spoken language. We support our view that exposure to Cued Speech before or after the implantation could be important in the aural rehabilitation process of cochlear implantees. We describe five lines of research that are converging to support the view that Cued Speech can enhance speech perception in individuals with cochlear implants. PMID:20724357

Working memory, short-term memory and reading proficiency in school-age children with cochlear implants.

PubMed

Bharadwaj, Sneha V; Maricle, Denise; Green, Laura; Allman, Tamby

2015-10-01

The objective of the study was to examine short-term memory and working memory through both visual and auditory tasks in school-age children with cochlear implants. The relationship between the performance on these cognitive skills and reading as well as language outcomes were examined in these children. Ten children between the ages of 7 and 11 years with early-onset bilateral severe-profound hearing loss participated in the study. Auditory and visual short-term memory, auditory and visual working memory subtests and verbal knowledge measures were assessed using the Woodcock Johnson III Tests of Cognitive Abilities, the Wechsler Intelligence Scale for Children-IV Integrated and the Kaufman Assessment Battery for Children II. Reading outcomes were assessed using the Woodcock Reading Mastery Test III. Performance on visual short-term memory and visual working memory measures in children with cochlear implants was within the average range when compared to the normative mean. However, auditory short-term memory and auditory working memory measures were below average when compared to the normative mean. Performance was also below average on all verbal knowledge measures. Regarding reading outcomes, children with cochlear implants scored below average for listening and passage comprehension tasks and these measures were positively correlated to visual short-term memory, visual working memory and auditory short-term memory. Performance on auditory working memory subtests was not related to reading or language outcomes. The children with cochlear implants in this study demonstrated better performance in visual (spatial) working memory and short-term memory skills than in auditory working memory and auditory short-term memory skills. Significant positive relationships were found between visual working memory and reading outcomes. The results of the study provide support for the idea that WM capacity is modality specific in children with hearing loss. Based on these findings, reading instruction that capitalizes on the strengths in visual short-term memory and working memory is suggested for young children with early-onset hearing loss. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Physiological Control of Molluscan Gill Cilia by 5-Hydroxytryptamine

PubMed Central

Gosselin, R. E.; Moore, K. E.; Milton, A. S.

1962-01-01

An examination is made of the hypothesis that endogenous 5-hydroxytryptamine (5-HT) serves as a local hormone regulating ciliary activity in the lamellibranch gill. These cilia are sensitive to exogenous 5-HT and respond to it by a prompt, sustained, and reversible rise in beat frequency; at the same time the carbohydrate metabolism is stimulated, as described elsewhere. Control gill contains small but definite amounts of endogenous 5-HT according to bioassay, fluorometry, and chromatography. The amount can be increased markedly by exposing the isolated gill to the precursor substance 5-hydroxytryptophan but not l-tryptophan. As the tissue level of 5-HT rises, the spontaneous beat frequency also rises. Both remain elevated for hours and perhaps for days. The gill of Mytilus edulis is richer than the gill of Modiolus demissus in both endogenous 5-HT and effective 5-hydroxytryptophan decarboxylase activity. Modiolus gill lacks the 5-hydroxyindole oxidase by which Mytilus gill destroys 5-HT. What if any mechanism exists in Modiolus for degrading 5-HT is not known, but monoamine oxidase is not present. The 5-HT content of Mytilus and Modiolus gill cannot be modified by treatment with reserpine or α-methyl-dopa. Which cells of the gill synthesize and destroy 5-HT has not been established, but these observations support the concept that the physiological activity of lamellibranch gill cilia is controlled by a serotonergic mechanism. PMID:13949402

Auditory, Visual, and Auditory-Visual Speech Perception by Individuals with Cochlear Implants versus Individuals with Hearing Aids

ERIC Educational Resources Information Center

Most, Tova; Rothem, Hilla; Luntz, Michal

2009-01-01

The researchers evaluated the contribution of cochlear implants (CIs) to speech perception by a sample of prelingually deaf individuals implanted after age 8 years. This group was compared with a group with profound hearing impairment (HA-P), and with a group with severe hearing impairment (HA-S), both of which used hearing aids. Words and…

High resolution micro-CT scanning as an innovative tool for evaluation of the surgical positioning of cochlear implant electrodes.

PubMed

Postnov, A; Zarowski, A; De Clerck, N; Vanpoucke, F; Offeciers, F E; Van Dyck, D; Peeters, S

2006-05-01

X-ray microtomography (micro-CT) is a new technique allowing for visualization of the internal structure of opaque specimens with a quasi-histological quality. Among multiple potential applications, the use of this technique in otology is very promising. Micro-CT appears to be ideally suited for in vitro visualization of the inner ear tissues as well as for evaluation of the electrode damage and/or surgical insertion trauma during implantation of the cochlear implant electrodes. This technique can greatly aid in design and development of new cochlear implant electrodes and is applicable for temporal bone studies. The main advantage of micro-CT is the practically artefact-free preparation of the samples and the possibility of evaluation of the interesting parameters along the whole insertion depth of the electrode. This paper presents the results of the first application of micro-CT for visualization of the inner ear structures in human temporal bones and for evaluation of the surgical positioning of the cochlear implant electrodes relative to the intracochlear soft tissues.

Serotonin projection patterns to the cochlear nucleus.

PubMed

Thompson, A M; Thompson, G C

2001-07-13

The cochlear nucleus is well known as an obligatory relay center for primary auditory nerve fibers. Perhaps not so well known is the neural input to the cochlear nucleus from cells containing serotonin that reside near the midline in the midbrain raphe region. Although the specific locations of the main, if not sole, sources of serotonin within the dorsal cochlear nucleus subdivision are known to be the dorsal and median raphe nuclei, sources of serotonin located within other cochlear nucleus subdivisions are not currently known. Anterograde tract tracing was used to label fibers originating from the dorsal and median raphe nuclei while fluorescence immunohistochemistry was used to simultaneously label specific serotonin fibers in cat. Biotinylated dextran amine was injected into the dorsal and median raphe nuclei and was visualized with Texas Red, while serotonin was visualized with fluorescein. Thus, double-labeled fibers were unequivocally identified as serotoninergic and originating from one of the labeled neurons within the dorsal and median raphe nuclei. Double-labeled fiber segments, typically of fine caliber with oval varicosities, were observed in many areas of the cochlear nucleus. They were found in the molecular layer of the dorsal cochlear nucleus, in the small cell cap region, and in the granule cell and external regions of the cochlear nuclei, bilaterally, of all cats. However, the density of these double-labeled fiber segments varied considerably depending upon the exact region in which they were found. Fiber segments were most dense in the dorsal cochlear nucleus (especially in the molecular layer) and the large spherical cell area of the anteroventral cochlear nucleus; they were moderately dense in the small cell cap region; and fiber segments were least dense in the octopus and multipolar cell regions of the posteroventral cochlear nucleus. Because of the presence of labeled fiber segments in subdivisions of the cochlear nucleus other than the dorsal cochlear nucleus, we concluded that the serotoninergic projection pattern to the cochlear nucleus is divergent and non-specific. Double-labeled fiber segments were also present, but sparse, in the superior olive, localized mainly in periolivary regions; this indicated that the divergence of dorsal and median raphe neurons that extends throughout regions of the cochlear nucleus also extended well beyond the cochlear nucleus to include at least the superior olivary complex as well.

The contribution of short-term memory capacity to reading ability in adolescents with cochlear implants.

PubMed

Edwards, Lindsey; Aitkenhead, Lynne; Langdon, Dawn

2016-11-01

This study aimed to establish the relationship between short-term memory capacity and reading skills in adolescents with cochlear implants. A between-groups design compared a group of young people with cochlear implants with a group of hearing peers on measures of reading, and auditory and visual short-term memory capacity. The groups were matched for non-verbal IQ and age. The adolescents with cochlear implants were recruited from the Cochlear Implant Programme at a specialist children's hospital. The hearing participants were recruited from the same schools as those attended by the implanted adolescents. Participants were 18 cochlear implant users and 14 hearing controls, aged between 12 and 18 years. All used English as their main language and had no significant learning disability or neuro-developmental disorder. Short-term memory capacity was assessed in the auditory modality using Forward and Reverse Digit Span from the WISC IV UK, and visually using Forward and Reverse Memory from the Leiter-R. Individual word reading, reading comprehension and pseudoword decoding were assessed using the WIAT II UK. A series of ANOVAs revealed that the adolescents with cochlear implants had significantly poorer auditory short-term memory capacity and reading skills (on all measures) compared with their hearing peers. However, when Forward Digit Span was entered into the analyses as a covariate, none of the differences remained statistically significant. Deficits in immediate auditory memory persist into adolescence in deaf children with cochlear implants. Short-term auditory memory capacity is an important neurocognitive process in the development of reading skills after cochlear implantation in childhood that remains evident in later adolescence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Low levels of microplastics (MP) in wild mussels indicate that MP ingestion by humans is minimal compared to exposure via household fibres fallout during a meal.

PubMed

Catarino, Ana I; Macchia, Valeria; Sanderson, William G; Thompson, Richard C; Henry, Theodore B

2018-06-01

Microplastics (MPs) are the most numerous debris reported in marine environments and assessment of the amounts of MPs that accumulate in wild organisms is necessary for risk assessment. Our objective was to assess MP contamination in mussels collected around the coast of Scotland (UK) to identify characteristics of MPs and to evaluate risk of human exposure to MPs via ingestion of mussels. We deployed caged mussels (Mytilus edulis) in an urbanised estuary (Edinburgh, UK) to assess seasonal changes in plastic pollution, and collected mussels (Mytilus spp and subtidal Modiolus modiolus) from eight sampling stations around Scotland to enumerate MP types at different locations. We determined the potential exposure of humans to household dust fibres during a meal to compare with amounts of MPs present in edible mussels. The mean number of MPs in M. modiolus was 0.086 ± 0.031 (SE, n = 6)/g ww (3.5 ± 1.29 (SE) per mussel). In Mytilus spp, the mean number of MPs/g ww was 3.0 ± 0.9 (SE, n = 36) (3.2 ± 0.52 (SE) per mussel), but weight dependent. The visual accuracy of plastic fibres identification was estimated to be between 48 and 50%, using Nile Red staining and FT-IR methodologies, respectively, halving the observed amounts of MPs in wild mussels. We observed an allometric relationship between the number of MPs and the mussels wet weight. Our predictions of MPs ingestion by humans via consumption of mussels is 123 MP particles/y/capita in the UK and can go up to 4620 particles/y/capita in countries with a higher shellfish consumption. By comparison, the risk of plastic ingestion via mussel consumption is minimal when compared to fibre exposure during a meal via dust fallout in a household (13,731-68,415 particles/Y/capita). Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Cadaveric feasibility study of da Vinci Si-assisted cochlear implant with augmented visual navigation for otologic surgery.

PubMed

Liu, Wen P; Azizian, Mahdi; Sorger, Jonathan; Taylor, Russell H; Reilly, Brian K; Cleary, Kevin; Preciado, Diego

2014-03-01

To our knowledge, this is the first reported cadaveric feasibility study of a master-slave-assisted cochlear implant procedure in the otolaryngology-head and neck surgery field using the da Vinci Si system (da Vinci Surgical System; Intuitive Surgical, Inc). We describe the surgical workflow adaptations using a minimally invasive system and image guidance integrating intraoperative cone beam computed tomography through augmented reality. To test the feasibility of da Vinci Si-assisted cochlear implant surgery with augmented reality, with visualization of critical structures and facilitation with precise cochleostomy for electrode insertion. Cadaveric case study of bilateral cochlear implant approaches conducted at Intuitive Surgical Inc, Sunnyvale, California. Bilateral cadaveric mastoidectomies, posterior tympanostomies, and cochleostomies were performed using the da Vinci Si system on a single adult human donor cadaveric specimen. Radiographic confirmation of successful cochleostomies, placement of a phantom cochlear implant wire, and visual confirmation of critical anatomic structures (facial nerve, cochlea, and round window) in augmented stereoendoscopy. With a surgical mean time of 160 minutes per side, complete bilateral cochlear implant procedures were successfully performed with no violation of critical structures, notably the facial nerve, chorda tympani, sigmoid sinus, dura, or ossicles. Augmented reality image overlay of the facial nerve, round window position, and basal turn of the cochlea was precise. Postoperative cone beam computed tomography scans confirmed successful placement of the phantom implant electrode array into the basal turn of the cochlea. To our knowledge, this is the first study in the otolaryngology-head and neck surgery literature examining the use of master-slave-assisted cochleostomy with augmented reality for cochlear implants using the da Vinci Si system. The described system for cochleostomy has the potential to improve the surgeon's confidence, as well as surgical safety, efficiency, and precision by filtering tremor. The integration of augmented reality may be valuable for surgeons dealing with complex cases of congenital anatomic abnormality, for revision cochlear implant with distorted anatomy and poorly pneumatized mastoids, and as a method of interactive teaching. Further research into the cost-benefit ratio of da Vinci Si-assisted otologic surgery, as well as refinements of the proposed workflow, are required before considering clinical studies.

How does visual language affect crossmodal plasticity and cochlear implant success?

PubMed Central

Lyness, C.R.; Woll, B.; Campbell, R.; Cardin, V.

2013-01-01

Cochlear implants (CI) are the most successful intervention for ameliorating hearing loss in severely or profoundly deaf children. Despite this, educational performance in children with CI continues to lag behind their hearing peers. From animal models and human neuroimaging studies it has been proposed the integrative functions of auditory cortex are compromised by crossmodal plasticity. This has been argued to result partly from the use of a visual language. Here we argue that ‘cochlear implant sensitive periods’ comprise both auditory and language sensitive periods, and thus cannot be fully described with animal models. Despite prevailing assumptions, there is no evidence to link the use of a visual language to poorer CI outcome. Crossmodal reorganisation of auditory cortex occurs regardless of compensatory strategies, such as sign language, used by the deaf person. In contrast, language deprivation during early sensitive periods has been repeatedly linked to poor language outcomes. Language sensitive periods have largely been ignored when considering variation in CI outcome, leading to ill-founded recommendations concerning visual language in CI habilitation. PMID:23999083

Comparing the effect of auditory-only and auditory-visual modes in two groups of Persian children using cochlear implants: a randomized clinical trial.

PubMed

Oryadi Zanjani, Mohammad Majid; Hasanzadeh, Saeid; Rahgozar, Mehdi; Shemshadi, Hashem; Purdy, Suzanne C; Mahmudi Bakhtiari, Behrooz; Vahab, Maryam

2013-09-01

Since the introduction of cochlear implantation, researchers have considered children's communication and educational success before and after implantation. Therefore, the present study aimed to compare auditory, speech, and language development scores following one-sided cochlear implantation between two groups of prelingual deaf children educated through either auditory-only (unisensory) or auditory-visual (bisensory) modes. A randomized controlled trial with a single-factor experimental design was used. The study was conducted in the Instruction and Rehabilitation Private Centre of Hearing Impaired Children and their Family, called Soroosh in Shiraz, Iran. We assessed 30 Persian deaf children for eligibility and 22 children qualified to enter the study. They were aged between 27 and 66 months old and had been implanted between the ages of 15 and 63 months. The sample of 22 children was randomly assigned to two groups: auditory-only mode and auditory-visual mode; 11 participants in each group were analyzed. In both groups, the development of auditory perception, receptive language, expressive language, speech, and speech intelligibility was assessed pre- and post-intervention by means of instruments which were validated and standardized in the Persian population. No significant differences were found between the two groups. The children with cochlear implants who had been instructed using either the auditory-only or auditory-visual modes acquired auditory, receptive language, expressive language, and speech skills at the same rate. Overall, spoken language significantly developed in both the unisensory group and the bisensory group. Thus, both the auditory-only mode and the auditory-visual mode were effective. Therefore, it is not essential to limit access to the visual modality and to rely solely on the auditory modality when instructing hearing, language, and speech in children with cochlear implants who are exposed to spoken language both at home and at school when communicating with their parents and educators prior to and after implantation. The trial has been registered at IRCT.ir, number IRCT201109267637N1. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Volumetric in vivo imaging of microvascular perfusion within the intact cochlea in mice using ultra-high sensitive optical microangiography.

PubMed

Subhash, Hrebesh M; Davila, Viviana; Sun, Hai; Nguyen-Huynh, Anh T; Shi, Xiaorui; Nuttall, Alfred L; Wang, Ruikang K

2011-02-01

Studying the inner ear microvascular dynamics is extremely important to understand the cochlear function and to further advance the diagnosis, prevention, and treatment of many otologic disorders. However, there is currently no effective imaging tool available that is able to access the blood flow within the intact cochlea. In this paper, we report the use of an ultrahigh sensitive optical micro-angiography (UHS-OMAG) imaging system to image 3-D microvascular perfusion within the intact cochlea in living mice. The UHS-OMAG image system used in this study is based on spectral domain optical coherence tomography, which uses a broadband light source centered at 1300 nm with an imaging rate of 47[Formula: see text] 000 A-scans/s, capable of acquiring high-resolution B scans at 300 frames/s. The technique is sensitive enough to image very slow blood flow velocities, such as those found in capillary networks. The 3-D imaging acquisition time for a whole cochlea is  ∼ 4.1 s. We demonstrate that volumetric reconstruction of microvascular flow obtained by UHS-OMAG provides a comprehensive perfusion map of several regions of the cochlea, including the otic capsule, the stria vascularis of the apical and middle turns and the radiating arterioles that emanate from the modiolus.

Concept Formation Skills in Long-Term Cochlear Implant Users

ERIC Educational Resources Information Center

Castellanos, Irina; Kronenberger, William G.; Beer, Jessica; Colson, Bethany G.; Henning, Shirley C.; Ditmars, Allison; Pisoni, David B.

2015-01-01

This study investigated if a period of auditory sensory deprivation followed by degraded auditory input and related language delays affects visual concept formation skills in long-term prelingually deaf cochlear implant (CI) users. We also examined if concept formation skills are mediated or moderated by other neurocognitive domains (i.e.,…

Is the Cochlear Amplifier a Fluid Pump?

NASA Astrophysics Data System (ADS)

Karavitaki, K. D.; Mountain, D. C.

2003-02-01

We have visualized and quantified the effects of electrically evoked motility of outer hair cells (OHCs) within the organ of Corti using an excised cochlear preparation. We found that OHC motility induces oscillatory fluid flow in the tunnel of Corti (TC) and this flow is present at physiologically relevant frequencies. We also show, using a simple one-dimensional hydromechanical model of the TC, that a fluid wave within the tunnel can travel without significant attenuation for distances larger than the wavelength of the cochlear traveling wave. These results in combination with a recent hypothesis that fluid flow within the tunnel is necessary for cochlear amplification suggest that the function of the OHCs is to act as a fluid pump.

Auditory-visual fusion in speech perception in children with cochlear implants

PubMed Central

Schorr, Efrat A.; Fox, Nathan A.; van Wassenhove, Virginie; Knudsen, Eric I.

2005-01-01

Speech, for most of us, is a bimodal percept whenever we both hear the voice and see the lip movements of a speaker. Children who are born deaf never have this bimodal experience. We tested children who had been deaf from birth and who subsequently received cochlear implants for their ability to fuse the auditory information provided by their implants with visual information about lip movements for speech perception. For most of the children with implants (92%), perception was dominated by vision when visual and auditory speech information conflicted. For some, bimodal fusion was strong and consistent, demonstrating a remarkable plasticity in their ability to form auditory-visual associations despite the atypical stimulation provided by implants. The likelihood of consistent auditory-visual fusion declined with age at implant beyond 2.5 years, suggesting a sensitive period for bimodal integration in speech perception. PMID:16339316

Deaf Parents of Cochlear-Implanted Children: Beliefs on Bimodal Bilingualism

ERIC Educational Resources Information Center

Mitchiner, Julie Cantrell

2015-01-01

This study investigated 17 Deaf families in North America with cochlear-implanted children about their attitudes, beliefs, and practices on bimodal bilingualism (defined as using both a visual/manual language and an aural/oral language) in American Sign Language (ASL) and English. A survey and follow-up interviews with 8 families were conducted.…

Hard X-Rays can BE Used to Visualize Cochlear Soft Tissue Displacements in a Closed Cochlea

NASA Astrophysics Data System (ADS)

Richter, C.-P.; Fishman, A.; Fan, L.; Shintani, S.; Rau, C.

2009-02-01

Experiments were made at the Advanced Photon Source (APS), Argonne National Laboratory. The APS is a synchrotron radiation source of the third generation, for which the particular characteristic is the highly coherent X-ray radiation. X-rays are generated with an undulator, inserted in a straight section of the storage ring. Images taken with hard X-rays at full field. A video flow algorithm by Lucas and Kanade was used to determine and quantify cochlear soft tissue displacements. The results show that displacements as low as 100 nm could be visualized.

Cochlear Pericytes Are Capable of Reversibly Decreasing Capillary Diameter In Vivo After Tumor Necrosis Factor Exposure.

PubMed

Bertlich, Mattis; Ihler, Friedrich; Weiss, Bernhard G; Freytag, Saskia; Strupp, Michael; Canis, Martin

2017-12-01

The aim of this work was to evaluate the effect of tumor necrosis factor (TNF) and its neutralization with etanercept on the capability of cochlear pericytes to alter capillary diameter in the stria vascularis. Twelve Dunkin-Hartley guinea pigs were randomly assigned to one of three groups. Each group was treated either with placebo and then placebo, TNF and then placebo, or TNF and then etanercept. Cochlear pericytes were visualized using diaminofluorescein-2-diacetate and intravasal blood flow by fluorescein-dextrane. Vessel diameter at sites of pericyte somas and downstream controls were quantified by specialized software. Values were obtained before treatment, after first treatment with tumor necrosis factor or placebo and after second treatment with etanercept or placebo. Overall, 199 pericytes in 12 animals were visualized. After initial treatment with TNF, a significant decrease in vessel diameter at sites of pericyte somas (3.6 ±4.3%, n = 141) compared with placebo and downstream controls was observed. After initial treatment with TNF, the application of etanercept caused a significant increase (3.3 ±5.5%, n = 59) in vessel diameter at the sites of pericyte somata compared with placebo and downstream controls. We have been able to show that cochlear pericytes are capable of reducing capillary diameter after exposition to TNF. Moreover, the reduction in capillary diameter observed after the application of TNF is revertible after neutralization of tumor necrosis factor by the application of etanercept. It seems that contraction of cochlear pericytes contributes to the regulation of cochlear blood flow.

Two-photon microscopy allows imaging and characterization of cochlear microvasculature in vivo.

PubMed

Ihler, Friedrich; Bertlich, Mattis; Weiss, Bernhard; Dietzel, Steffen; Canis, Martin

2015-01-01

Impairment of cochlear blood flow has been discussed as factor in the pathophysiology of various inner ear disorders. However, the microscopic study of cochlear microcirculation is limited due to small scale and anatomical constraints. Here, two-photon fluorescence microscopy is applied to visualize cochlear microvessels. Guinea pigs were injected with Fluorescein isothiocyanate- or Texas red-dextrane as plasma marker. Intravital microscopy was performed in four animals and explanted cochleae from four animals were studied. The vascular architecture of the cochlea was visualized up to a depth of 90.0±22.7 μm. Imaging yielded a mean contrast-to-noise ratio (CNR) of 3.3±1.7. Mean diameter in vivo was 16.5±6.0 μm for arterioles and 8.0±2.4 μm for capillaries. In explanted cochleae, the diameter of radiating arterioles and capillaries was measured with 12.2±1.6 μm and 6.6±1.0 μm, respectively. The difference between capillaries and arterioles was statistically significant in both experimental setups (P<0.001 and P=0.022, two-way ANOVA). Measured vessel diameters in vivo and ex vivo were in agreement with published data. We conclude that two-photon fluorescence microscopy allows the investigation of cochlear microvessels and is potentially a valuable tool for inner ear research.

Auditory, visual, and auditory-visual perception of emotions by individuals with cochlear implants, hearing AIDS, and normal hearing.

PubMed

Most, Tova; Aviner, Chen

2009-01-01

This study evaluated the benefits of cochlear implant (CI) with regard to emotion perception of participants differing in their age of implantation, in comparison to hearing aid users and adolescents with normal hearing (NH). Emotion perception was examined by having the participants identify happiness, anger, surprise, sadness, fear, and disgust. The emotional content was placed upon the same neutral sentence. The stimuli were presented in auditory, visual, and combined auditory-visual modes. The results revealed better auditory identification by the participants with NH in comparison to all groups of participants with hearing loss (HL). No differences were found among the groups with HL in each of the 3 modes. Although auditory-visual perception was better than visual-only perception for the participants with NH, no such differentiation was found among the participants with HL. The results question the efficiency of some currently used CIs in providing the acoustic cues required to identify the speaker's emotional state.

Language Processing in Children with Cochlear Implants: A Preliminary Report on Lexical Access for Production and Comprehension

ERIC Educational Resources Information Center

Schwartz, Richard G.; Steinman, Susan; Ying, Elizabeth; Mystal, Elana Ying; Houston, Derek M.

2013-01-01

In this plenary paper, we present a review of language research in children with cochlear implants along with an outline of a 5-year project designed to examine the lexical access for production and recognition. The project will use auditory priming, picture naming with auditory or visual interfering stimuli (Picture-Word Interference and…

Developmental dysgraphia with profound hearing impairment: intervention by auditory methods enabled by cochlear implant.

PubMed

Fukushima, Kunihiro; Kawasaki, Akihiro; Nagayasu, Rie; Kunisue, Kazuya; Maeda, Yukihide; Kariya, Shin; Kataoka, Yuko; Nishizaki, Kazunori

2008-06-01

Learning disability combined with hearing impairment (LDHI) is a poor prognostic factor for the language development of hearing impaired children after educational intervention. A typical example of a child with LDHI and effective interventions provided by cochlear implants are presented in this report. A case of congenital cytomegaloviral infection that showed dysgraphia as well as profound deafness was reported and an underlying visual processing problem diagnosed in the present case caused the patient's dysgraphia. The dysgraphia could be circumvented by the use of auditory memory fairly established by a cochlear implant.

Music activities and responses of young cochlear implant recipients.

PubMed

van Besouw, Rachel M; Grasmeder, Mary L; Hamilton, Mary E; Baumann, Sarah E

2011-05-01

The development of auditory receptive skills and spoken language is often delayed in children who use cochlear implants, which may affect their appreciation of and responses to music. This in turn may be interpreted as disinterest in music. A questionnaire was developed to determine whether differences in exposure and responses to music exist between young cochlear implant recipients and their normally hearing peers. The questionnaire was developed by a multidisciplinary team and distributed to parents of preschool children with normal hearing and to parents of preschool children who had been implanted at least one year prior. The cochlear implant group comprised 23 children and was gender and age matched (within ±2 months) to a group of children with normal hearing. Young cochlear implant recipients receive similar exposure to audiovisual music media, parental singing and musical instruments at home. However, the data suggest that they receive less exposure to children's music presented without visual stimuli. Parents also reported less sophisticated responses to music for this group. The findings of this study have important implications concerning the provision of age-appropriate music habilitation materials and activities for young cochlear implant recipients.

The red tide event in El Salvador, August 2001-January 2002.

PubMed

Enrique Barraza, José; Armero-Guardado, Julio; Valencia de Toledo, Zobeyda Marisol

2004-09-01

A red tide event occurred in El Salvador from August 2001 to January 2002. National health authorities usually measured toxin levels in Ostrea iridescens, however other species were analyzed during this microalgae bloom: Anadara similis, Anadara tuberculosa and Modiolus sp. El Salvador authorities consider 400 mouse units/100 g the highest value that is safe for human health. During this period toxin levels in 0. iridescens and Modiolus sp. increased from values under 400 to 3977 and 15,468 mouse units/100 g, respectively. Persistent and higher levels were recorded in oyster and mussel banks on the west part of the country. The Ministry of Health and Social Assistance treated 41 slight to moderate intoxications associated to bivalve mollusks consumption.

A software tool for analyzing multichannel cochlear implant signals.

PubMed

Lai, Wai Kong; Bögli, Hans; Dillier, Norbert

2003-10-01

A useful and convenient means to analyze the radio frequency (RF) signals being sent by a speech processor to a cochlear implant would be to actually capture and display them with appropriate software. This is particularly useful for development or diagnostic purposes. sCILab (Swiss Cochlear Implant Laboratory) is such a PC-based software tool intended for the Nucleus family of Multichannel Cochlear Implants. Its graphical user interface provides a convenient and intuitive means for visualizing and analyzing the signals encoding speech information. Both numerical and graphic displays are available for detailed examination of the captured CI signals, as well as an acoustic simulation of these CI signals. sCILab has been used in the design and verification of new speech coding strategies, and has also been applied as an analytical tool in studies of how different parameter settings of existing speech coding strategies affect speech perception. As a diagnostic tool, it is also useful for troubleshooting problems with the external equipment of the cochlear implant systems.

A phone-assistive device based on Bluetooth technology for cochlear implant users.

PubMed

Qian, Haifeng; Loizou, Philipos C; Dorman, Michael F

2003-09-01

Hearing-impaired people, and particularly hearing-aid and cochlear-implant users, often have difficulty communicating over the telephone. The intelligibility of telephone speech is considerably lower than the intelligibility of face-to-face speech. This is partly because of lack of visual cues, limited telephone bandwidth, and background noise. In addition, cellphones may cause interference with the hearing aid or cochlear implant. To address these problems that hearing-impaired people experience with telephones, this paper proposes a wireless phone adapter that can be used to route the audio signal directly to the hearing aid or cochlear implant processor. This adapter is based on Bluetooth technology. The favorable features of this new wireless technology make the adapter superior to traditional assistive listening devices. A hardware prototype was built and software programs were written to implement the headset profile in the Bluetooth specification. Three cochlear implant users were tested with the proposed phone-adapter and reported good speech quality.

Experimental flat-panel high-spatial-resolution volume CT of the temporal bone.

PubMed

Gupta, Rajiv; Bartling, Soenke H; Basu, Samit K; Ross, William R; Becker, Hartmut; Pfoh, Armin; Brady, Thomas; Curtin, Hugh D

2004-09-01

A CT scanner employing a digital flat-panel detector is capable of very high spatial resolution as compared with a multi-section CT (MSCT) scanner. Our purpose was to determine how well a prototypical volume CT (VCT) scanner with a flat-panel detector system defines fine structures in temporal bone. Four partially manipulated temporal-bone specimens were imaged by use of a prototypical cone-beam VCT scanner with a flat-panel detector system at an isometric resolution of 150 microm at the isocenter. These specimens were also depicted by state-of-the-art multisection CT (MSCT). Forty-two structures imaged by both scanners were qualitatively assessed and rated, and scores assigned to VCT findings were compared with those of MSCT. Qualitative assessment of anatomic structures, lesions, cochlear implants, and middle-ear hearing aids indicated that image quality was significantly better with VCT (P < .001). Structures near the spatial-resolution limit of MSCT (e.g., bony covering of the tympanic segment of the facial canal, the incudo-stapedial joint, the proximal vestibular aqueduct, the interscalar septum, and the modiolus) had higher contrast and less partial-volume effect with VCT. The flat-panel prototype provides better definition of fine osseous structures of temporal bone than that of currently available MSCT scanners. This study provides impetus for further research in increasing spatial resolution beyond that offered by the current state-of-the-art scanners.

McGurk stimuli for the investigation of multisensory integration in cochlear implant users: The Oldenburg Audio Visual Speech Stimuli (OLAVS).

PubMed

Stropahl, Maren; Schellhardt, Sebastian; Debener, Stefan

2017-06-01

The concurrent presentation of different auditory and visual syllables may result in the perception of a third syllable, reflecting an illusory fusion of visual and auditory information. This well-known McGurk effect is frequently used for the study of audio-visual integration. Recently, it was shown that the McGurk effect is strongly stimulus-dependent, which complicates comparisons across perceivers and inferences across studies. To overcome this limitation, we developed the freely available Oldenburg audio-visual speech stimuli (OLAVS), consisting of 8 different talkers and 12 different syllable combinations. The quality of the OLAVS set was evaluated with 24 normal-hearing subjects. All 96 stimuli were characterized based on their stimulus disparity, which was obtained from a probabilistic model (cf. Magnotti & Beauchamp, 2015). Moreover, the McGurk effect was studied in eight adult cochlear implant (CI) users. By applying the individual, stimulus-independent parameters of the probabilistic model, the predicted effect of stronger audio-visual integration in CI users could be confirmed, demonstrating the validity of the new stimulus material.

Usefulness of Intravital Multiphoton Microscopy in Visualizing Study of Mouse Cochlea and Volume Changes in the Scala Media

PubMed Central

Ju, Hyun Mi; Lee, Sun Hee; Kong, Tae Hoon; Kwon, Seung-Hae; Choi, Jin Sil; Seo, Young Joon

2017-01-01

Conventional microscopy has limitations in viewing the cochlear microstructures due to three-dimensional spiral structure and the overlying bone. But these issues can be overcome by imaging the cochlea in vitro with intravital multiphoton microscopy (MPM). By using near-infrared lasers for multiphoton excitation, intravital MPM can detect endogenous fluorescence and second harmonic generation of tissues. In this study, we used intravital MPM to visualize various cochlear microstructures without any staining and non-invasively analyze the volume changes of the scala media (SM) without removing the overlying cochlear bone. The intravital MPM images revealed various tissue types, ranging from thin membranes to dense bone, as well as the spiral ganglion beneath the cochlear bone. The two-dimensional, cross-sectional, and serial z-stack intravital MPM images also revealed the spatial dilation of the SM in the temporal bone of pendrin-deficient mice. These findings suggest that intravital MPM might serve as a new method for obtaining microanatomical information regarding the cochlea, similar to standard histopathological analyses in the animal study for the cochlea. Given the capability of intravital MPM for detecting an increase in the volume of the SM in pendrin-deficient mice, it might be a promising new tool for assessing the pathophysiology of hearing loss in the future. PMID:28824523

Retrofacial approach to access the round window for cochlear implantation of malformed ears.

PubMed

Rizk, Habib; O'Connell, Brendan; Stevens, Shawn; Meyer, Ted

2015-03-01

To report the use of the retrofacial approach for cochlear implantation in three cases of malformed ears with inaccessible round windows through the standard facial recess. Two children with bilateral profound sensorineural hearing loss who were cochlear implant candidates. One patient had bilateral sequential cochlear implantations and the other a unilateral implant. Retrofacial approach to access the posterior mesotympanum and visualize the round window. Ability to complete the surgery with full insertion of the implant and no complications such as facial nerve injury. We implanted three ears in two patients with multiple external and middle ear malformations with an aberrant facial nerve or a posteriorly displaced round window niche. The standard facial recess approach did not allow visualization of the round window. We resorted to a retrofacial approach to access the posterior mesotympanum and proceeded with the surgery through an anterior and inferior cochleostomy or through the round window. In cases with an aberrant facial nerve or inaccessible round window through the facial recess, the retrofacial approach is a good alternative but requires a certain level of expertise and familiarity with temporal bone anatomy. The decision to use an unconventional approach should be considered before surgery, but the ultimate decision may require intraoperative assessment.

Usefulness of Intravital Multiphoton Microscopy in Visualizing Study of Mouse Cochlea and Volume Changes in the Scala Media.

PubMed

Ju, Hyun Mi; Lee, Sun Hee; Kong, Tae Hoon; Kwon, Seung-Hae; Choi, Jin Sil; Seo, Young Joon

2017-01-01

Conventional microscopy has limitations in viewing the cochlear microstructures due to three-dimensional spiral structure and the overlying bone. But these issues can be overcome by imaging the cochlea in vitro with intravital multiphoton microscopy (MPM). By using near-infrared lasers for multiphoton excitation, intravital MPM can detect endogenous fluorescence and second harmonic generation of tissues. In this study, we used intravital MPM to visualize various cochlear microstructures without any staining and non-invasively analyze the volume changes of the scala media (SM) without removing the overlying cochlear bone. The intravital MPM images revealed various tissue types, ranging from thin membranes to dense bone, as well as the spiral ganglion beneath the cochlear bone. The two-dimensional, cross-sectional, and serial z-stack intravital MPM images also revealed the spatial dilation of the SM in the temporal bone of pendrin-deficient mice. These findings suggest that intravital MPM might serve as a new method for obtaining microanatomical information regarding the cochlea, similar to standard histopathological analyses in the animal study for the cochlea. Given the capability of intravital MPM for detecting an increase in the volume of the SM in pendrin-deficient mice, it might be a promising new tool for assessing the pathophysiology of hearing loss in the future.

Evolution of crossmodal reorganization of the voice area in cochlear-implanted deaf patients.

PubMed

Rouger, Julien; Lagleyre, Sébastien; Démonet, Jean-François; Fraysse, Bernard; Deguine, Olivier; Barone, Pascal

2012-08-01

Psychophysical and neuroimaging studies in both animal and human subjects have clearly demonstrated that cortical plasticity following sensory deprivation leads to a brain functional reorganization that favors the spared modalities. In postlingually deaf patients, the use of a cochlear implant (CI) allows a recovery of the auditory function, which will probably counteract the cortical crossmodal reorganization induced by hearing loss. To study the dynamics of such reversed crossmodal plasticity, we designed a longitudinal neuroimaging study involving the follow-up of 10 postlingually deaf adult CI users engaged in a visual speechreading task. While speechreading activates Broca's area in normally hearing subjects (NHS), the activity level elicited in this region in CI patients is abnormally low and increases progressively with post-implantation time. Furthermore, speechreading in CI patients induces abnormal crossmodal activations in right anterior regions of the superior temporal cortex normally devoted to processing human voice stimuli (temporal voice-sensitive areas-TVA). These abnormal activity levels diminish with post-implantation time and tend towards the levels observed in NHS. First, our study revealed that the neuroplasticity after cochlear implantation involves not only auditory but also visual and audiovisual speech processing networks. Second, our results suggest that during deafness, the functional links between cortical regions specialized in face and voice processing are reallocated to support speech-related visual processing through cross-modal reorganization. Such reorganization allows a more efficient audiovisual integration of speech after cochlear implantation. These compensatory sensory strategies are later completed by the progressive restoration of the visuo-audio-motor speech processing loop, including Broca's area. Copyright © 2011 Wiley Periodicals, Inc.

Evaluation of non-rigid registration parameters for atlas-based segmentation of CT images of human cochlea

NASA Astrophysics Data System (ADS)

Elfarnawany, Mai; Alam, S. Riyahi; Agrawal, Sumit K.; Ladak, Hanif M.

2017-02-01

Cochlear implant surgery is a hearing restoration procedure for patients with profound hearing loss. In this surgery, an electrode is inserted into the cochlea to stimulate the auditory nerve and restore the patient's hearing. Clinical computed tomography (CT) images are used for planning and evaluation of electrode placement, but their low resolution limits the visualization of internal cochlear structures. Therefore, high resolution micro-CT images are used to develop atlas-based segmentation methods to extract these nonvisible anatomical features in clinical CT images. Accurate registration of the high and low resolution CT images is a prerequisite for reliable atlas-based segmentation. In this study, we evaluate and compare different non-rigid B-spline registration parameters using micro-CT and clinical CT images of five cadaveric human cochleae. The varying registration parameters are cost function (normalized correlation (NC), mutual information and mean square error), interpolation method (linear, windowed-sinc and B-spline) and sampling percentage (1%, 10% and 100%). We compare the registration results visually and quantitatively using the Dice similarity coefficient (DSC), Hausdorff distance (HD) and absolute percentage error in cochlear volume. Using MI or MSE cost functions and linear or windowed-sinc interpolation resulted in visually undesirable deformation of internal cochlear structures. Quantitatively, the transforms using 100% sampling percentage yielded the highest DSC and smallest HD (0.828+/-0.021 and 0.25+/-0.09mm respectively). Therefore, B-spline registration with cost function: NC, interpolation: B-spline and sampling percentage: moments 100% can be the foundation of developing an optimized atlas-based segmentation algorithm of intracochlear structures in clinical CT images.

Cochlear implants and spoken language processing abilities: review and assessment of the literature.

PubMed

Peterson, Nathaniel R; Pisoni, David B; Miyamoto, Richard T

2010-01-01

Cochlear implants (CIs) process sounds electronically and then transmit electric stimulation to the cochlea of individuals with sensorineural deafness, restoring some sensation of auditory perception. Many congenitally deaf CI recipients achieve a high degree of accuracy in speech perception and develop near-normal language skills. Post-lingually deafened implant recipients often regain the ability to understand and use spoken language with or without the aid of visual input (i.e. lip reading). However, there is wide variation in individual outcomes following cochlear implantation, and some CI recipients never develop useable speech and oral language skills. The causes of this enormous variation in outcomes are only partly understood at the present time. The variables most strongly associated with language outcomes are age at implantation and mode of communication in rehabilitation. Thus, some of the more important factors determining success of cochlear implantation are broadly related to neural plasticity that appears to be transiently present in deaf individuals. In this article we review the expected outcomes of cochlear implantation, potential predictors of those outcomes, the basic science regarding critical and sensitive periods, and several new research directions in the field of cochlear implantation.

3D optical coherence tomography image registration for guiding cochlear implant insertion

NASA Astrophysics Data System (ADS)

Cheon, Gyeong-Woo; Jeong, Hyun-Woo; Chalasani, Preetham; Chien, Wade W.; Iordachita, Iulian; Taylor, Russell; Niparko, John; Kang, Jin U.

2014-03-01

In cochlear implant surgery, an electrode array is inserted into the cochlear canal to restore hearing to a person who is profoundly deaf or significantly hearing impaired. One critical part of the procedure is the insertion of the electrode array, which looks like a thin wire, into the cochlear canal. Although X-ray or computed tomography (CT) could be used as a reference to evaluate the pathway of the whole electrode array, there is no way to depict the intra-cochlear canal and basal turn intra-operatively to help guide insertion of the electrode array. Optical coherent tomography (OCT) is a highly effective way of visualizing internal structures of cochlea. Swept source OCT (SSOCT) having center wavelength of 1.3 micron and 2D Galvonometer mirrors was used to achieve 7-mm depth 3-D imaging. Graphics processing unit (GPU), OpenGL, C++ and C# were integrated for real-time volumetric rendering simultaneously. The 3D volume images taken by the OCT system were assembled and registered which could be used to guide a cochlear implant. We performed a feasibility study using both dry and wet temporal bones and the result is presented.

Crossmodal interactions during non-linguistic auditory processing in cochlear-implanted deaf patients.

PubMed

Barone, Pascal; Chambaudie, Laure; Strelnikov, Kuzma; Fraysse, Bernard; Marx, Mathieu; Belin, Pascal; Deguine, Olivier

2016-10-01

Due to signal distortion, speech comprehension in cochlear-implanted (CI) patients relies strongly on visual information, a compensatory strategy supported by important cortical crossmodal reorganisations. Though crossmodal interactions are evident for speech processing, it is unclear whether a visual influence is observed in CI patients during non-linguistic visual-auditory processing, such as face-voice interactions, which are important in social communication. We analyse and compare visual-auditory interactions in CI patients and normal-hearing subjects (NHS) at equivalent auditory performance levels. Proficient CI patients and NHS performed a voice-gender categorisation in the visual-auditory modality from a morphing-generated voice continuum between male and female speakers, while ignoring the presentation of a male or female visual face. Our data show that during the face-voice interaction, CI deaf patients are strongly influenced by visual information when performing an auditory gender categorisation task, in spite of maximum recovery of auditory speech. No such effect is observed in NHS, even in situations of CI simulation. Our hypothesis is that the functional crossmodal reorganisation that occurs in deafness could influence nonverbal processing, such as face-voice interaction; this is important for patient internal supramodal representation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Beyond Keyword Search: Representations and Models for Personalization

DTIC Science & Technology

2013-01-29

model of information flow in the blogosphere. Blogscope is intended to be an analysis and visualization tool for the blogosphere. Unlike us, they are...Compressive nonlinearity in the hair bundle’s active response to mechanical stimulation 2001 98 14386-14391 10123 In vivo evidence for a cochlear ...p)ppGpp in plant signaling 2000 97 3747-3752 12176 Cochlear mechanisms from a phylogenetic viewpoint 2000 97 11736-11743 12270 Putting ion channels

Implicit sequence learning in deaf children with cochlear implants.

PubMed

Conway, Christopher M; Pisoni, David B; Anaya, Esperanza M; Karpicke, Jennifer; Henning, Shirley C

2011-01-01

Deaf children with cochlear implants (CIs) represent an intriguing opportunity to study neurocognitive plasticity and reorganization when sound is introduced following a period of auditory deprivation early in development. Although it is common to consider deafness as affecting hearing alone, it may be the case that auditory deprivation leads to more global changes in neurocognitive function. In this paper, we investigate implicit sequence learning abilities in deaf children with CIs using a novel task that measured learning through improvement to immediate serial recall for statistically consistent visual sequences. The results demonstrated two key findings. First, the deaf children with CIs showed disturbances in their visual sequence learning abilities relative to the typically developing normal-hearing children. Second, sequence learning was significantly correlated with a standardized measure of language outcome in the CI children. These findings suggest that a period of auditory deprivation has secondary effects related to general sequencing deficits, and that disturbances in sequence learning may at least partially explain why some deaf children still struggle with language following cochlear implantation. © 2010 Blackwell Publishing Ltd.

Artificial organs: recent progress in artificial hearing and vision.

PubMed

Ifukube, Tohru

2009-01-01

Artificial sensory organs are a prosthetic means of sending visual or auditory information to the brain by electrical stimulation of the optic or auditory nerves to assist visually impaired or hearing-impaired people. However, clinical application of artificial sensory organs, except for cochlear implants, is still a trial-and-error process. This is because how and where the information transmitted to the brain is processed is still unknown, and also because changes in brain function (plasticity) remain unknown, even though brain plasticity plays an important role in meaningful interpretation of new sensory stimuli. This article discusses some basic unresolved issues and potential solutions in the development of artificial sensory organs such as cochlear implants, brainstem implants, artificial vision, and artificial retinas.

Audio-visual speech perception in prelingually deafened Japanese children following sequential bilateral cochlear implantation.

PubMed

Yamamoto, Ryosuke; Naito, Yasushi; Tona, Risa; Moroto, Saburo; Tamaya, Rinko; Fujiwara, Keizo; Shinohara, Shogo; Takebayashi, Shinji; Kikuchi, Masahiro; Michida, Tetsuhiko

2017-11-01

An effect of audio-visual (AV) integration is observed when the auditory and visual stimuli are incongruent (the McGurk effect). In general, AV integration is helpful especially in subjects wearing hearing aids or cochlear implants (CIs). However, the influence of AV integration on spoken word recognition in individuals with bilateral CIs (Bi-CIs) has not been fully investigated so far. In this study, we investigated AV integration in children with Bi-CIs. The study sample included thirty one prelingually deafened children who underwent sequential bilateral cochlear implantation. We assessed their responses to congruent and incongruent AV stimuli with three CI-listening modes: only the 1st CI, only the 2nd CI, and Bi-CIs. The responses were assessed in the whole group as well as in two sub-groups: a proficient group (syllable intelligibility ≥80% with the 1st CI) and a non-proficient group (syllable intelligibility < 80% with the 1st CI). We found evidence of the McGurk effect in each of the three CI-listening modes. AV integration responses were observed in a subset of incongruent AV stimuli, and the patterns observed with the 1st CI and with Bi-CIs were similar. In the proficient group, the responses with the 2nd CI were not significantly different from those with the 1st CI whereas in the non-proficient group the responses with the 2nd CI were driven by visual stimuli more than those with the 1st CI. Our results suggested that prelingually deafened Japanese children who underwent sequential bilateral cochlear implantation exhibit AV integration abilities, both in monaural listening as well as in binaural listening. We also observed a higher influence of visual stimuli on speech perception with the 2nd CI in the non-proficient group, suggesting that Bi-CIs listeners with poorer speech recognition rely on visual information more compared to the proficient subjects to compensate for poorer auditory input. Nevertheless, poorer quality auditory input with the 2nd CI did not interfere with AV integration with binaural listening (with Bi-CIs). Overall, the findings of this study might be used to inform future research to identify the best strategies for speech training using AV integration effectively in prelingually deafened children. Copyright © 2017 Elsevier B.V. All rights reserved.

CT of the ear in Pendred syndrome.

PubMed

Goldfeld, Moshe; Glaser, Benjamin; Nassir, Elias; Gomori, John Moshe; Hazani, Elitsur; Bishara, Nassir

2005-05-01

To prospectively determine the structural anomalies of the inner ear by using thin-section computed tomography (CT) in an extended family with Pendred syndrome. Ethics committee approved the study, and informed consent was obtained from every patient or from parents of patients under legal age. Twelve patients (three females and nine males aged 7-47 years) with Pendred syndrome (all from the same ethnic isolate and with the same mutation in the PDS gene) were evaluated for inner-ear malformation at thin-section CT. Both ears were evaluated. Presence or absence of interscalar septum between upper and middle turns of the cochlea was evaluated, and vestibule and vestibular aqueduct were examined for enlargement. Modiolus was determined to be present or absent (modiolar deficiency). CT scans were evaluated in consensus by two radiologists (M.G., J.M.G.). All patients had inner ear malformation on both sides. Modiolus was absent and vestibule was enlarged on both sides in all 12 patients. Interscalar septum was absent in 18 (75%) of 24 ears. In eight patients, interscalar septum was absent in both ears, whereas in two patients, it was absent on only one side. Aqueduct was enlarged in 20 (80%) of 24 ears. In nine patients, both ears had enlarged aqueducts, while in two patients, only one side was abnormal. Inner ear malformation is an invariable finding in Pendred syndrome. Modiolus deficiency and vestibular enlargement were the most consistent anomalies in this population with Pendred syndrome. (c) RSNA, 2005.

Effects of congruent and incongruent visual cues on speech perception and brain activity in cochlear implant users.

PubMed

Song, Jae-Jin; Lee, Hyo-Jeong; Kang, Hyejin; Lee, Dong Soo; Chang, Sun O; Oh, Seung Ha

2015-03-01

While deafness-induced plasticity has been investigated in the visual and auditory domains, not much is known about language processing in audiovisual multimodal environments for patients with restored hearing via cochlear implant (CI) devices. Here, we examined the effect of agreeing or conflicting visual inputs on auditory processing in deaf patients equipped with degraded artificial hearing. Ten post-lingually deafened CI users with good performance, along with matched control subjects, underwent H 2 (15) O-positron emission tomography scans while carrying out a behavioral task requiring the extraction of speech information from unimodal auditory stimuli, bimodal audiovisual congruent stimuli, and incongruent stimuli. Regardless of congruency, the control subjects demonstrated activation of the auditory and visual sensory cortices, as well as the superior temporal sulcus, the classical multisensory integration area, indicating a bottom-up multisensory processing strategy. Compared to CI users, the control subjects exhibited activation of the right ventral premotor-supramarginal pathway. In contrast, CI users activated primarily the visual cortices more in the congruent audiovisual condition than in the null condition. In addition, compared to controls, CI users displayed an activation focus in the right amygdala for congruent audiovisual stimuli. The most notable difference between the two groups was an activation focus in the left inferior frontal gyrus in CI users confronted with incongruent audiovisual stimuli, suggesting top-down cognitive modulation for audiovisual conflict. Correlation analysis revealed that good speech performance was positively correlated with right amygdala activity for the congruent condition, but negatively correlated with bilateral visual cortices regardless of congruency. Taken together these results suggest that for multimodal inputs, cochlear implant users are more vision-reliant when processing congruent stimuli and are disturbed more by visual distractors when confronted with incongruent audiovisual stimuli. To cope with this multimodal conflict, CI users activate the left inferior frontal gyrus to adopt a top-down cognitive modulation pathway, whereas normal hearing individuals primarily adopt a bottom-up strategy.

The Role of Visual Speech Information in Supporting Perceptual Learning of Degraded Speech

ERIC Educational Resources Information Center

Wayne, Rachel V.; Johnsrude, Ingrid S.

2012-01-01

Following cochlear implantation, hearing-impaired listeners must adapt to speech as heard through their prosthesis. Visual speech information (VSI; the lip and facial movements of speech) is typically available in everyday conversation. Here, we investigate whether learning to understand a popular auditory simulation of speech as transduced by a…

Trimodal speech perception: how residual acoustic hearing supplements cochlear-implant consonant recognition in the presence of visual cues.

PubMed

Sheffield, Benjamin M; Schuchman, Gerald; Bernstein, Joshua G W

2015-01-01

As cochlear implant (CI) acceptance increases and candidacy criteria are expanded, these devices are increasingly recommended for individuals with less than profound hearing loss. As a result, many individuals who receive a CI also retain acoustic hearing, often in the low frequencies, in the nonimplanted ear (i.e., bimodal hearing) and in some cases in the implanted ear (i.e., hybrid hearing) which can enhance the performance achieved by the CI alone. However, guidelines for clinical decisions pertaining to cochlear implantation are largely based on expectations for postsurgical speech-reception performance with the CI alone in auditory-only conditions. A more comprehensive prediction of postimplant performance would include the expected effects of residual acoustic hearing and visual cues on speech understanding. An evaluation of auditory-visual performance might be particularly important because of the complementary interaction between the speech information relayed by visual cues and that contained in the low-frequency auditory signal. The goal of this study was to characterize the benefit provided by residual acoustic hearing to consonant identification under auditory-alone and auditory-visual conditions for CI users. Additional information regarding the expected role of residual hearing in overall communication performance by a CI listener could potentially lead to more informed decisions regarding cochlear implantation, particularly with respect to recommendations for or against bilateral implantation for an individual who is functioning bimodally. Eleven adults 23 to 75 years old with a unilateral CI and air-conduction thresholds in the nonimplanted ear equal to or better than 80 dB HL for at least one octave frequency between 250 and 1000 Hz participated in this study. Consonant identification was measured for conditions involving combinations of electric hearing (via the CI), acoustic hearing (via the nonimplanted ear), and speechreading (visual cues). The results suggest that the benefit to CI consonant-identification performance provided by the residual acoustic hearing is even greater when visual cues are also present. An analysis of consonant confusions suggests that this is because the voicing cues provided by the residual acoustic hearing are highly complementary with the mainly place-of-articulation cues provided by the visual stimulus. These findings highlight the need for a comprehensive prediction of trimodal (acoustic, electric, and visual) postimplant speech-reception performance to inform implantation decisions. The increased influence of residual acoustic hearing under auditory-visual conditions should be taken into account when considering surgical procedures or devices that are intended to preserve acoustic hearing in the implanted ear. This is particularly relevant when evaluating the candidacy of a current bimodal CI user for a second CI (i.e., bilateral implantation). Although recent developments in CI technology and surgical techniques have increased the likelihood of preserving residual acoustic hearing, preservation cannot be guaranteed in each individual case. Therefore, the potential gain to be derived from bilateral implantation needs to be weighed against the possible loss of the benefit provided by residual acoustic hearing.

Cross-modal perception of rhythm in music and dance by cochlear implant users.

PubMed

Vongpaisal, Tara; Monaghan, Melanie

2014-05-01

Two studies examined adult cochlear implant (CI) users' ability to match auditory rhythms occurring in music to visual rhythms occurring in dance (Cha Cha, Slow Swing, Tango and Jive). In Experiment 1, adults CI users (n = 10) and hearing controls matched a music excerpt to choreographed dance sequences presented as silent videos. In Experiment 2, participants matched a silent video of a dance sequence to music excerpts. CI users were successful in detecting timing congruencies across music and dance at well above-chance levels suggesting that they were able to process distinctive auditory and visual rhythm patterns that characterized each style. However, they were better able to detect cross-modal timing congruencies when the reference was an auditory rhythm than when the reference was a visual rhythm. Learning strategies that encourage cross-modal learning of musical rhythms may have applications in developing novel rehabilitative strategies to enhance music perception and appreciation outcomes of child implant users.

Pediatric cochlear implants: additional disabilities prevalence, risk factors, and effect on language outcomes.

PubMed

Birman, Catherine S; Elliott, Elizabeth J; Gibson, William P R

2012-10-01

To determine the prevalence of additional disabilities in a pediatric cochlear population, to identify medical and radiologic conditions associated with additional disabilities, and to identify the effect of additional disabilities on speech perception and language at 12 months postoperatively. Retrospective case review. Tertiary referral center and cochlear implant program. Records were reviewed for children 0 to 16 years old inclusive, who had cochlear implant-related operations over a 12-month period. Diagnostic and rehabilitative. Additional disabilities prevalence; medical history and radiologic abnormalities; and the effect on Categories of Auditory Performance (CAP) score at 12 months postoperatively. Eighty-eight children having 96 operations were identified. The overall prevalence of additional disabilities (including developmental delay, cerebral palsy, visual impairment, autism and attention deficit disorder) was 33%. The main conditions associated with additional disabilities were syndromes and chromosomal abnormalities (87%), jaundice (86%), prematurity (62%), cytomegalovirus (60%), and inner ear abnormalities including cochlea nerve hypoplasia or aplasia (75%) and semicircular canal anomalies (56%). At 12 months postoperatively, almost all (96%) of the children without additional disabilities had a CAP score of 5 or greater (speech), compared with 52% of children with additional disabilities. Children with developmental delay had a median CAP score of 4, at 12 months compared with 6 for those without developmental delay. Additional disabilities are prevalent in approximately a third of pediatric cochlear implant patients. Additional disabilities significantly affect the outcomes of cochlear implants.

High-resolution T1-weighted 3D real IR imaging of the temporal bone using triple-dose contrast material.

PubMed

Naganawa, Shinji; Koshikawa, Tokiko; Nakamura, Tatsuya; Fukatsu, Hiroshi; Ishigaki, Takeo; Aoki, Ikuo

2003-12-01

The small structures in the temporal bone are surrounded by bone and air. The objectives of this study were (a) to compare contrast-enhanced T1-weighted images acquired by fast spin-echo-based three-dimensional real inversion recovery (3D rIR) against those acquired by gradient echo-based 3D SPGR in the visualization of the enhancement of small structures in the temporal bone, and (b) to determine whether either 3D rIR or 3D SPGR is useful for visualizing enhancement of the cochlear lymph fluid. Seven healthy men (age range 27-46 years) volunteered to participate in this study. All MR imaging was performed using a dedicated bilateral quadrature surface phased-array coil for temporal bone imaging at 1.5 T (Visart EX, Toshiba, Tokyo, Japan). The 3D rIR images (TR/TE/TI: 1800 ms/10 ms/500 ms) and flow-compensated 3D SPGR images (TR/TE/FA: 23 ms/10 ms/25 degrees) were obtained with a reconstructed voxel size of 0.6 x 0.7 x 0.8 mm3. Images were acquired before and 1, 90, 180, and 270 min after the administration of triple-dose Gd-DTPA-BMA (0.3 mmol/kg). In post-contrast MR images, the degree of enhancement of the cochlear aqueduct, endolymphatic sac, subarcuate artery, geniculate ganglion of the facial nerve, and cochlear lymph fluid space was assessed by two radiologists. The degree of enhancement was scored as follows: 0 (no enhancement); 1 (slight enhancement); 2 (intermediate between 1 and 3); and 3 (enhancement similar to that of vessels). Enhancement scores for the endolymphatic sac, subarcuate artery, and geniculate ganglion were higher in 3D rIR than in 3D SPGR. Washout of enhancement in the endolymphatic sac appeared to be delayed compared with that in the subarcuate artery, suggesting that the enhancement in the endolymphatic sac may have been due in part to non-vascular tissue enhancement. Enhancement of the cochlear lymph space was not observed in any of the subjects in 3D rIR and 3D SPGR. The 3D rIR sequence may be more sensitive than the 3D SPGR sequence in visualizing the enhancement of small structures in the temporal bone; however, enhancement of the cochlear fluid space could not be visualized even with 3D rIR, triple-dose contrast, and dedicated coils at 1.5 T.

Auditory Preferences of Young Children with and without Hearing Loss for Meaningful Auditory-Visual Compound Stimuli

ERIC Educational Resources Information Center

Zupan, Barbra; Sussman, Joan E.

2009-01-01

Experiment 1 examined modality preferences in children and adults with normal hearing to combined auditory-visual stimuli. Experiment 2 compared modality preferences in children using cochlear implants participating in an auditory emphasized therapy approach to the children with normal hearing from Experiment 1. A second objective in both…

Phase contrast tomography of the mouse cochlea at microfocus x-ray sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bartels, Matthias; Krenkel, Martin; Hernandez, Victor H.

2013-08-19

We present phase contrast x-ray tomography of functional soft tissue within the bony cochlear capsule of mice, carried out at laboratory microfocus sources with well-matched source, detector, geometry, and reconstruction algorithms at spatial resolutions down to 2 μm. Contrast, data quality and resolution enable the visualization of thin membranes and nerve fibers as well as automated segmentation of surrounding bone. By complementing synchrotron radiation imaging techniques, a broad range of biomedical applications becomes possible as demonstrated for optogenetic cochlear implant research.

Interaction of tinnitus suppression and hearing ability after cochlear implantation.

PubMed

Wang, Qian; Li, Jia-Nan; Lei, Guan-Xiong; Chen, Dai-Shi; Wang, Wei-Ze; Chen, Ai-Ting; Mong, Meng-Di; Li, Sun; Jiao, Qing-Shan; Yang, Shi-Ming

2017-10-01

To study the postoperative impact of cochlear implants (CIs) on tinnitus, as well as the impact of tinnitus on speech recognition with CI switched on. Fifty-two postlingual deafened CI recipients (21 males and 31 females) were assessed using an established Tinnitus Characteristics Questionnaire and Tinnitus Handicap Inventory (THI) before and after cochlear implantation. The tinnitus loudness was investigated when CI was switched on and off in CI recipients with persistent tinnitus. The relation between tinnitus loudness and recipients' satisfaction of cochlear implantation was analyzed by the visual analogue scale (VAS) score. With CI 'OFF', 42 CI recipients experienced tinnitus postimplant ipsilaterally and 44 contralaterally. Tinnitus was totally suppressed ipsilateral to the CI with CI 'ON' in 42.9%, partially suppressed in 42.9%, unchanged in 11.9% and aggravated in 2.4%. Tinnitus was totally suppressed contralaterally with CI 'ON' in 31.8% of CI recipients, partially suppressed in 47.7%, unchanged in 20.5%. Pearson correlation analysis showed that tinnitus loudness and the results of cochlear implant patients satisfaction was negatively correlated (r = .674, p < .001). The study suggests six-month CI activation can be effective for suppressing tinnitus. The tinnitus loudness may affect patients' satisfaction with the use of CI.

HRCT Correlation with Round Window Identification during Cochlear Implantation in Children.

PubMed

Pendem, Sai Kiran; Rangasami, Rajeswaran; Arunachalam, Ravi Kumar; Mohanarangam, Venkata Sai Pulivadulu; Natarajan, Paarthipan

2014-01-01

To determine the accuracy of High Resolution Computer Tomography (HRCT) temporal bone measurements in predicting the actual visualization of round window niche as viewed through posterior tympanotomy (i.e. facial recess). This is a prospective study of 37 cochlear implant candidates, aged between 1and 6 years, who were referred for HRCT temporal bone during the period December 2013 to July 2014. Cochlear implantation was done in 37 children (25 in the right ear and 12 in the left ear). The distance between the short process of incus and the round window niche and the distance between the oval window and the round window niche were measured preoperatively on sub-millimeter (0.7 mm) HRCT images. We classified the visibility of round window niche based on the surgical view (i.e. through posterior tympanotomy) during surgery into three types: 1) Type 1- fully visible, 2) Type 2- partially visible, and 3) Type 3- difficult to visualize. The preoperative HRCT measurements were used to predict the type of visualization of round window niche before surgery and correlated with the findings during surgery. The mean and standard deviation for the distance between the short process of incus and the round window niche and for the distance between the oval window and the round window niche for Types 1, 2, and 3 were 8.5 ± 0.2 mm and 3.2 ± 0.2 mm, 8.0 ± 0.4 mm and 3.8 ± 0.2 mm, 7.5 ± 0.2 mm and 4.4 ± 0.2 mm respectively, and showed statistically significant difference (P < 0.01) between them. The preoperative HRCT measurements had a sensitivity and specificity of 92.3% and 96.2%, respectively, in determining the actual visualization of round window niche. This study shows preoperative HRCT temporal bone measurements are useful in predicting the actual visualization of round window niche as viewed through posterior tympanotomy.

Emotional recognition of dynamic facial expressions before and after cochlear implantation in adults with progressive deafness.

PubMed

Ambert-Dahan, Emmanuèle; Giraud, Anne-Lise; Mecheri, Halima; Sterkers, Olivier; Mosnier, Isabelle; Samson, Séverine

2017-10-01

Visual processing has been extensively explored in deaf subjects in the context of verbal communication, through the assessment of speech reading and sign language abilities. However, little is known about visual emotional processing in adult progressive deafness, and after cochlear implantation. The goal of our study was thus to assess the influence of acquired post-lingual progressive deafness on the recognition of dynamic facial emotions that were selected to express canonical fear, happiness, sadness, and anger. A total of 23 adults with post-lingual deafness separated into two groups; those assessed either before (n = 10) and those assessed after (n = 13) cochlear implantation (CI); and 13 normal hearing (NH) individuals participated in the current study. Participants were asked to rate the expression of the four cardinal emotions, and to evaluate both their emotional valence (unpleasant-pleasant) and arousal potential (relaxing-stimulating). We found that patients with deafness were impaired in the recognition of sad faces, and that patients equipped with a CI were additionally impaired in the recognition of happiness and fear (but not anger). Relative to controls, all patients with deafness showed a deficit in perceiving arousal expressed in faces, while valence ratings remained unaffected. The current results show for the first time that acquired and progressive deafness is associated with a reduction of emotional sensitivity to visual stimuli. This negative impact of progressive deafness on the perception of dynamic facial cues for emotion recognition contrasts with the proficiency of deaf subjects with and without CIs in processing visual speech cues (Rouger et al., 2007; Strelnikov et al., 2009; Lazard and Giraud, 2017). Altogether these results suggest there to be a trade-off between the processing of linguistic and non-linguistic visual stimuli. Copyright © 2017. Published by Elsevier B.V.

The contribution of visual information to the perception of speech in noise with and without informative temporal fine structure

PubMed Central

Stacey, Paula C.; Kitterick, Pádraig T.; Morris, Saffron D.; Sumner, Christian J.

2017-01-01

Understanding what is said in demanding listening situations is assisted greatly by looking at the face of a talker. Previous studies have observed that normal-hearing listeners can benefit from this visual information when a talker's voice is presented in background noise. These benefits have also been observed in quiet listening conditions in cochlear-implant users, whose device does not convey the informative temporal fine structure cues in speech, and when normal-hearing individuals listen to speech processed to remove these informative temporal fine structure cues. The current study (1) characterised the benefits of visual information when listening in background noise; and (2) used sine-wave vocoding to compare the size of the visual benefit when speech is presented with or without informative temporal fine structure. The accuracy with which normal-hearing individuals reported words in spoken sentences was assessed across three experiments. The availability of visual information and informative temporal fine structure cues was varied within and across the experiments. The results showed that visual benefit was observed using open- and closed-set tests of speech perception. The size of the benefit increased when informative temporal fine structure cues were removed. This finding suggests that visual information may play an important role in the ability of cochlear-implant users to understand speech in many everyday situations. Models of audio-visual integration were able to account for the additional benefit of visual information when speech was degraded and suggested that auditory and visual information was being integrated in a similar way in all conditions. The modelling results were consistent with the notion that audio-visual benefit is derived from the optimal combination of auditory and visual sensory cues. PMID:27085797

Auditory and audio-visual processing in patients with cochlear, auditory brainstem, and auditory midbrain implants: An EEG study.

PubMed

Schierholz, Irina; Finke, Mareike; Kral, Andrej; Büchner, Andreas; Rach, Stefan; Lenarz, Thomas; Dengler, Reinhard; Sandmann, Pascale

2017-04-01

There is substantial variability in speech recognition ability across patients with cochlear implants (CIs), auditory brainstem implants (ABIs), and auditory midbrain implants (AMIs). To better understand how this variability is related to central processing differences, the current electroencephalography (EEG) study compared hearing abilities and auditory-cortex activation in patients with electrical stimulation at different sites of the auditory pathway. Three different groups of patients with auditory implants (Hannover Medical School; ABI: n = 6, CI: n = 6; AMI: n = 2) performed a speeded response task and a speech recognition test with auditory, visual, and audio-visual stimuli. Behavioral performance and cortical processing of auditory and audio-visual stimuli were compared between groups. ABI and AMI patients showed prolonged response times on auditory and audio-visual stimuli compared with NH listeners and CI patients. This was confirmed by prolonged N1 latencies and reduced N1 amplitudes in ABI and AMI patients. However, patients with central auditory implants showed a remarkable gain in performance when visual and auditory input was combined, in both speech and non-speech conditions, which was reflected by a strong visual modulation of auditory-cortex activation in these individuals. In sum, the results suggest that the behavioral improvement for audio-visual conditions in central auditory implant patients is based on enhanced audio-visual interactions in the auditory cortex. Their findings may provide important implications for the optimization of electrical stimulation and rehabilitation strategies in patients with central auditory prostheses. Hum Brain Mapp 38:2206-2225, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Reproduction of auditory and visual standards in monochannel cochlear implant users.

PubMed

Kanabus, Magdalena; Szelag, Elzbieta; Kolodziejczyk, Iwona; Szuchnik, Joanna

2004-01-01

The temporal reproduction of standard durations ranging from 1 to 9 seconds was investigated in monochannel cochlear implant (CI) users and in normally hearing subjects for the auditory and visual modality. The results showed that the pattern of performance in patients depended on their level of auditory comprehension. Results for CI users, who displayed relatively good auditory comprehension, did not differ from that of normally hearing subjects for both modalities. Patients with poor auditory comprehension significantly overestimated shorter auditory standards (1, 1.5 and 2.5 s), compared to both patients with good comprehension and controls. For the visual modality the between-group comparisons were not significant. These deficits in the reproduction of auditory standards were explained in accordance with both the attentional-gate model and the role of working memory in prospective time judgment. The impairments described above can influence the functioning of the temporal integration mechanism that is crucial for auditory speech comprehension on the level of words and phrases. We postulate that the deficits in time reproduction of short standards may be one of the possible reasons for poor speech understanding in monochannel CI users.

Evaluation of a new mid-scala cochlear implant electrode using microcomputed tomography.

PubMed

Frisch, Christopher D; Carlson, Matthew L; Lane, John I; Driscoll, Colin L W

2015-12-01

To investigate electrode position, depth of insertion, and electrode contact using an electrode array with a mid-scala design following round window (RW) and cochleostomy insertion. Eight fresh-frozen cadaveric bones were implanted; half via a RW approach and half through an anteroinferior cochleostomy using a styleted mid-scala electrode design. Microcomputed tomography was used to acquire oblique coronal and oblique axial reformations. Individual electrode positions along each array, insertional depth, and electrode contact were determined using National Institutes of Health Image J software. All electrodes were inserted without significant resistance. The average angular depth of insertion was 436.5° for the RW group and 422.7° for the cochleostomy group. All electrodes acquired a perimodiolar position in the proximal segment and a lateral wall position at the basal turn, regardless of approach. Electrodes distal to the basal turn demonstrated a variable location, with 78% mid scala. One cochleostomy array fractured through the interscalar partition (ISP), acquiring a scala vestibuli position. The odds ratio for either abutting the modiolus, ISP, lateral wall or floor, or fracturing through the ISP were 2.7 times more likely following a cochleostomy insertion (P = .032). The styleted mid-scala electrode design acquires a proximal perimodiolar position, a lateral wall location, as it traverses the basal turn, and most commonly a mid-scala position in the distal array. Interscalar excursion occurred in one of the cochleostomy insertions. Cochleostomy insertion is more likely to result in ultimate final electrode position adjacent to critical intracochlear structures. NA. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Innervation of the cow's inner ear derived from micro-computed tomography

NASA Astrophysics Data System (ADS)

Costeur, Loic; Mennecart, Bastien; Khimchenko, Anna; Müller, Bert; Schulz, Georg

2017-09-01

The innervation of the inner ear has been thoroughly investigated in humans and in some animal models such as the guinea pig, the rabbit, the cat, the dog, the rat, the pig and some monkeys. Ruminant inner ears are still poorly known and their innervation was never investigated despite its potential interest in phylogenetic reconstructions. Following earlier works on the ontogeny of the cow's ear, we expand our understanding of this structure by reconstructing the fine innervation pattern of the inner ear of the cow in two ontogenetic stages, at 7 months gestation and at an adult age. Since we work on dry skeletal specimens, only the endocast of the innervation inside the petrosal bone was reconstructed up to the internal acoustic meatus. The paths of the facial and vestibulocochlear nerves could be reconstructed together with that of the spiral ganglion canal. The nerves have a very fibrous pattern. The bony cavities of the ampular and utricular branches of the vestibulocochlear nerve could also be reconstructed. Our observations confirm that not all bony structures are present in foetal stages since the branch of cranial nerve VII is not visible on the foetus but very broad on the adult stage. The fibrous pattern within the modiolus connecting the spiral canal to the cochlear nerve is also less dense than in the adult stage. The shape of the branch of cranial nerve VII is very broad in the cow ending in a large hiatus Fallopii; this, together with the above-mentioned particularities, could constitute relevant observations for phylogenetical purposes when more data will be made available.

Partial corrosion casting to assess cochlear vasculature in mouse models of presbycusis and CMV infection.

PubMed

Carraro, Mattia; Park, Albert H; Harrison, Robert V

2016-02-01

Some forms of sensorineural hearing loss involve damage or degenerative changes to the stria vascularis and/or other vascular structures in the cochlea. In animal models, many methods for anatomical assessment of cochlear vasculature exist, each with advantages and limitations. One methodology, corrosion casting, has proved useful in some species, however in the mouse model this technique is difficult to achieve because digestion of non vascular tissue results in collapse of the delicate cast specimen. We have developed a partial corrosion cast method that allows visualization of vasculature along much of the cochlear length but maintains some structural integrity of the specimen. We provide a detailed step-by-step description of this novel technique. We give some illustrative examples of the use of the method in mouse models of presbycusis and cytomegalovirus (CMV) infection. Copyright © 2015 Elsevier B.V. All rights reserved.

Audiovisual sentence repetition as a clinical criterion for auditory development in Persian-language children with hearing loss.

PubMed

Oryadi-Zanjani, Mohammad Majid; Vahab, Maryam; Rahimi, Zahra; Mayahi, Anis

2017-02-01

It is important for clinician such as speech-language pathologists and audiologists to develop more efficient procedures to assess the development of auditory, speech and language skills in children using hearing aid and/or cochlear implant compared to their peers with normal hearing. So, the aim of study was the comparison of the performance of 5-to-7-year-old Persian-language children with and without hearing loss in visual-only, auditory-only, and audiovisual presentation of sentence repetition task. The research was administered as a cross-sectional study. The sample size was 92 Persian 5-7 year old children including: 60 with normal hearing and 32 with hearing loss. The children with hearing loss were recruited from Soroush rehabilitation center for Persian-language children with hearing loss in Shiraz, Iran, through consecutive sampling method. All the children had unilateral cochlear implant or bilateral hearing aid. The assessment tool was the Sentence Repetition Test. The study included three computer-based experiments including visual-only, auditory-only, and audiovisual. The scores were compared within and among the three groups through statistical tests in α = 0.05. The score of sentence repetition task between V-only, A-only, and AV presentation was significantly different in the three groups; in other words, the highest to lowest scores belonged respectively to audiovisual, auditory-only, and visual-only format in the children with normal hearing (P < 0.01), cochlear implant (P < 0.01), and hearing aid (P < 0.01). In addition, there was no significant correlationship between the visual-only and audiovisual sentence repetition scores in all the 5-to-7-year-old children (r = 0.179, n = 92, P = 0.088), but audiovisual sentence repetition scores were found to be strongly correlated with auditory-only scores in all the 5-to-7-year-old children (r = 0.943, n = 92, P = 0.000). According to the study's findings, audiovisual integration occurs in the 5-to-7-year-old Persian children using hearing aid or cochlear implant during sentence repetition similar to their peers with normal hearing. Therefore, it is recommended that audiovisual sentence repetition should be used as a clinical criterion for auditory development in Persian-language children with hearing loss. Copyright © 2016. Published by Elsevier B.V.

Audio-visual speech intelligibility benefits with bilateral cochlear implants when talker location varies.

PubMed

van Hoesel, Richard J M

2015-04-01

One of the key benefits of using cochlear implants (CIs) in both ears rather than just one is improved localization. It is likely that in complex listening scenes, improved localization allows bilateral CI users to orient toward talkers to improve signal-to-noise ratios and gain access to visual cues, but to date, that conjecture has not been tested. To obtain an objective measure of that benefit, seven bilateral CI users were assessed for both auditory-only and audio-visual speech intelligibility in noise using a novel dynamic spatial audio-visual test paradigm. For each trial conducted in spatially distributed noise, first, an auditory-only cueing phrase that was spoken by one of four talkers was selected and presented from one of four locations. Shortly afterward, a target sentence was presented that was either audio-visual or, in another test configuration, audio-only and was spoken by the same talker and from the same location as the cueing phrase. During the target presentation, visual distractors were added at other spatial locations. Results showed that in terms of speech reception thresholds (SRTs), the average improvement for bilateral listening over the better performing ear alone was 9 dB for the audio-visual mode, and 3 dB for audition-alone. Comparison of bilateral performance for audio-visual and audition-alone showed that inclusion of visual cues led to an average SRT improvement of 5 dB. For unilateral device use, no such benefit arose, presumably due to the greatly reduced ability to localize the target talker to acquire visual information. The bilateral CI speech intelligibility advantage over the better ear in the present study is much larger than that previously reported for static talker locations and indicates greater everyday speech benefits and improved cost-benefit than estimated to date.

Enhanced audio-visual interactions in the auditory cortex of elderly cochlear-implant users.

PubMed

Schierholz, Irina; Finke, Mareike; Schulte, Svenja; Hauthal, Nadine; Kantzke, Christoph; Rach, Stefan; Büchner, Andreas; Dengler, Reinhard; Sandmann, Pascale

2015-10-01

Auditory deprivation and the restoration of hearing via a cochlear implant (CI) can induce functional plasticity in auditory cortical areas. How these plastic changes affect the ability to integrate combined auditory (A) and visual (V) information is not yet well understood. In the present study, we used electroencephalography (EEG) to examine whether age, temporary deafness and altered sensory experience with a CI can affect audio-visual (AV) interactions in post-lingually deafened CI users. Young and elderly CI users and age-matched NH listeners performed a speeded response task on basic auditory, visual and audio-visual stimuli. Regarding the behavioral results, a redundant signals effect, that is, faster response times to cross-modal (AV) than to both of the two modality-specific stimuli (A, V), was revealed for all groups of participants. Moreover, in all four groups, we found evidence for audio-visual integration. Regarding event-related responses (ERPs), we observed a more pronounced visual modulation of the cortical auditory response at N1 latency (approximately 100 ms after stimulus onset) in the elderly CI users when compared with young CI users and elderly NH listeners. Thus, elderly CI users showed enhanced audio-visual binding which may be a consequence of compensatory strategies developed due to temporary deafness and/or degraded sensory input after implantation. These results indicate that the combination of aging, sensory deprivation and CI facilitates the coupling between the auditory and the visual modality. We suggest that this enhancement in multisensory interactions could be used to optimize auditory rehabilitation, especially in elderly CI users, by the application of strong audio-visually based rehabilitation strategies after implant switch-on. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of experimental otter trawling on benthic assemblages on Western Bank, northwest Atlantic Ocean

NASA Astrophysics Data System (ADS)

Kenchington, Ellen L. R.; Gilkinson, Kent D.; MacIsaac, Kevin G.; Bourbonnais-Boyce, Cynthia; Kenchington, Trevor J.; Smith, Stephen J.; Gordon, Donald C., Jr.

2006-10-01

The effects of otter trawling on a hard-bottom ecosystem on Western Bank on Canada's Scotian Shelf were examined experimentally from 1997 to 1999 with an asymmetrical BACI design. The site was located within an area that had been closed to fishing since 1987 to protect juvenile haddock. An experimental line was trawled 12-14 times on three separate occasions over a 20 month period. The benthic macrofauna and megafauna were sampled before and after trawling on both impact and control lines with both a grab and a photographic system. The 100 grab samples collected contained 341 taxa, primarily polychaetes, amphipods and molluscs, the majority (60%) of which were epifaunal. Biomass was dominated by the horse-mussel Modiolus modiolus, a long-lived bivalve, while the tube-building amphipod Ericthonius fasciatus was the most abundant species. Through the study period the benthos on the control lines showed little qualitative or quantitative change in individual taxa or community metrics. However, the abundance of 24 individual taxa (polychaetes, amphipods, echinoderms and molluscs) changed significantly, with the majority of these increasing. This resulted in a significantly different relative abundance of taxa between years as detected through ANOSIM. A significant change in relative biomass amongst the taxa was also observed. Trawling had few detectable immediate effects on the abundance or biomass of individual taxa and none on community composition. A few taxa, primarily a mixture of polychaetes and amphipods, decreased significantly after trawling and data from fish stomachs collected during the experiment (Kenchington, E.L., Gordon Jr., D.C., Bourbonnais-Boyce, C., MacIsaac, K.G., Gilkinson, K.D., McKeown, D.L., Vass, W.P., 2005. Effects of experimental otter trawling on the feeding of demersal fish on Western Bank, Nova Scotia. Amer. Fish. Soc. Symp. 41, 391-409) showed that some of these were scavenged by demersal fish. Fifteen taxa showed significant decreases after trawling when the cumulative effects of trawling were considered. As in the analyses of individual years the species affected were primarily high turn-over species such as polychaetes and amphipods. Dominance curves prepared for both control and impact samples before trawling in 1997 and after trawling in 1999 showed a marked decrease in the biomass values of the highest ranking taxa, particularly of the first species, M. modiolus, only on the impact line at the conclusion of the experiment. The proportion of epifaunal biomass also declined significantly from 90% to 77% on the impact line by the conclusion of the experiment. These changes are in part due to trawl-induced damage and subsequent predation by demersal fish of the top ranking species. Analysis of the photographic images showed that the three top-ranking species in terms of biomass, M. modiolus, the tube-building polychaete Thelepus cincinnatus, and the brachiopod Terebratulina septentrionalis, were visibly damaged more than other species by the trawl gear. Two of these species, M. modiolus and T. cincinnatus, were preyed upon by scavenging demersal fish. The use of multiple sampling devices at the experimental site (grab, photographic system reported here and trawl and fish stomachs reported by Kenchington, E.L., Gordon Jr., D.C., Bourbonnais-Boyce, C., MacIsaac, K.G., Gilkinson, K.D., McKeown, D.L., Vass, W.P., 2005. Effects of experimental otter trawling on the feeding of demersal fish on Western Bank, Nova Scotia. Amer. Fish. Soc. Symp. 41, 391-409) enabled us to link trawl-induced changes to the benthos to predation by demersal fish.

Differences between mechanical and neural tuning at the apex of the intact guinea pig cochlea

NASA Astrophysics Data System (ADS)

Recio-Spinoso, Alberto; Oghalai, John S.

2018-05-01

While most of human speech information is contained within frequencies < 3-4 kHz, only a few mechanical measurements have been made in cochlear regions responsive to such low frequencies. Furthermore, the data that do exist are difficult to interpret given the technical difficulties in performing the experiments and/or the artifacts that result from opening the otic capsule bone to visualize the organ of Corti. Here, we overcame historical technical limitations and non-invasively measured sound-induced vibrations within the apex of the guinea pig cochlea using volumetric optical coherence tomography vibrometry (VOCTV). We found that vibrations within apical cochlear regions, with neural tuning below 2 kHz, demonstrate low-pass filter characteristics. There was evidence of a low-level of broad-band cochlear amplification that did not sharpen frequency selectivity. We compared the vibratory responses we measured to previously-measured single-unit auditory nerve tuning curves in the same frequency range, and found that mechanical responses do not match neural responses. These data suggest that, for low frequency cochlear regions, inner hair cells not only transduce vibrations of the organ of Corti but also sharpen frequency tuning.

Changes in otoacoustic emissions during selective auditory and visual attention

PubMed Central

Walsh, Kyle P.; Pasanen, Edward G.; McFadden, Dennis

2015-01-01

Previous studies have demonstrated that the otoacoustic emissions (OAEs) measured during behavioral tasks can have different magnitudes when subjects are attending selectively or not attending. The implication is that the cognitive and perceptual demands of a task can affect the first neural stage of auditory processing—the sensory receptors themselves. However, the directions of the reported attentional effects have been inconsistent, the magnitudes of the observed differences typically have been small, and comparisons across studies have been made difficult by significant procedural differences. In this study, a nonlinear version of the stimulus-frequency OAE (SFOAE), called the nSFOAE, was used to measure cochlear responses from human subjects while they simultaneously performed behavioral tasks requiring selective auditory attention (dichotic or diotic listening), selective visual attention, or relative inattention. Within subjects, the differences in nSFOAE magnitude between inattention and attention conditions were about 2–3 dB for both auditory and visual modalities, and the effect sizes for the differences typically were large for both nSFOAE magnitude and phase. These results reveal that the cochlear efferent reflex is differentially active during selective attention and inattention, for both auditory and visual tasks, although they do not reveal how attention is improved when efferent activity is greater. PMID:25994703

Minimal effects of visual memory training on the auditory performance of adult cochlear implant users

PubMed Central

Oba, Sandra I.; Galvin, John J.; Fu, Qian-Jie

2014-01-01

Auditory training has been shown to significantly improve cochlear implant (CI) users’ speech and music perception. However, it is unclear whether post-training gains in performance were due to improved auditory perception or to generally improved attention, memory and/or cognitive processing. In this study, speech and music perception, as well as auditory and visual memory were assessed in ten CI users before, during, and after training with a non-auditory task. A visual digit span (VDS) task was used for training, in which subjects recalled sequences of digits presented visually. After the VDS training, VDS performance significantly improved. However, there were no significant improvements for most auditory outcome measures (auditory digit span, phoneme recognition, sentence recognition in noise, digit recognition in noise), except for small (but significant) improvements in vocal emotion recognition and melodic contour identification. Post-training gains were much smaller with the non-auditory VDS training than observed in previous auditory training studies with CI users. The results suggest that post-training gains observed in previous studies were not solely attributable to improved attention or memory, and were more likely due to improved auditory perception. The results also suggest that CI users may require targeted auditory training to improve speech and music perception. PMID:23516087

Talker and lexical effects on audiovisual word recognition by adults with cochlear implants.

PubMed

Kaiser, Adam R; Kirk, Karen Iler; Lachs, Lorin; Pisoni, David B

2003-04-01

The present study examined how postlingually deafened adults with cochlear implants combine visual information from lipreading with auditory cues in an open-set word recognition task. Adults with normal hearing served as a comparison group. Word recognition performance was assessed using lexically controlled word lists presented under auditory-only, visual-only, and combined audiovisual presentation formats. Effects of talker variability were studied by manipulating the number of talkers producing the stimulus tokens. Lexical competition was investigated using sets of lexically easy and lexically hard test words. To assess the degree of audiovisual integration, a measure of visual enhancement, R(a), was used to assess the gain in performance provided in the audiovisual presentation format relative to the maximum possible performance obtainable in the auditory-only format. Results showed that word recognition performance was highest for audiovisual presentation followed by auditory-only and then visual-only stimulus presentation. Performance was better for single-talker lists than for multiple-talker lists, particularly under the audiovisual presentation format. Word recognition performance was better for the lexically easy than for the lexically hard words regardless of presentation format. Visual enhancement scores were higher for single-talker conditions compared to multiple-talker conditions and tended to be somewhat better for lexically easy words than for lexically hard words. The pattern of results suggests that information from the auditory and visual modalities is used to access common, multimodal lexical representations in memory. The findings are discussed in terms of the complementary nature of auditory and visual sources of information that specify the same underlying gestures and articulatory events in speech.

Talker and Lexical Effects on Audiovisual Word Recognition by Adults With Cochlear Implants

PubMed Central

Kaiser, Adam R.; Kirk, Karen Iler; Lachs, Lorin; Pisoni, David B.

2012-01-01

The present study examined how postlingually deafened adults with cochlear implants combine visual information from lipreading with auditory cues in an open-set word recognition task. Adults with normal hearing served as a comparison group. Word recognition performance was assessed using lexically controlled word lists presented under auditory-only, visual-only, and combined audiovisual presentation formats. Effects of talker variability were studied by manipulating the number of talkers producing the stimulus tokens. Lexical competition was investigated using sets of lexically easy and lexically hard test words. To assess the degree of audiovisual integration, a measure of visual enhancement, Ra, was used to assess the gain in performance provided in the audiovisual presentation format relative to the maximum possible performance obtainable in the auditory-only format. Results showed that word recognition performance was highest for audiovisual presentation followed by auditory-only and then visual-only stimulus presentation. Performance was better for single-talker lists than for multiple-talker lists, particularly under the audiovisual presentation format. Word recognition performance was better for the lexically easy than for the lexically hard words regardless of presentation format. Visual enhancement scores were higher for single-talker conditions compared to multiple-talker conditions and tended to be somewhat better for lexically easy words than for lexically hard words. The pattern of results suggests that information from the auditory and visual modalities is used to access common, multimodal lexical representations in memory. The findings are discussed in terms of the complementary nature of auditory and visual sources of information that specify the same underlying gestures and articulatory events in speech. PMID:14700380

The rat cochlea in the absence of circulating adrenal hormones: an electrophysiological and morphological study.

PubMed

Lohuis, P J; Börjesson, P K; Klis, S F; Smoorenburg, G F

2000-05-01

Circulating adrenal hormones affect strial function. Removal of endogenous levels of adrenal steroids by bilateral adrenalectomy (ADX) in rats causes a decrease of Na(+)/K(+)-ATPase activity in the cochlear lateral wall [Rarey et al., 1989. Arch. Otolaryngol. Head Neck Surg. 115, 817-821] and a decrease of the volume of the marginal cells in the stria vascularis [Lohuis et al., 1990. Acta Otolaryngol. (Stockh.) 110, 348-356]. To study further the effect of absence of circulating adrenocorticosteroids on cochlear function, 18 male Long Evans rats underwent either an ADX or a SHAM operation. Electrocochleography was performed 1 week after surgery for tone bursts in a frequency range of 1-16 kHz. Thereafter, the cochleas were harvested and examined histologically. No significant changes in the amplitude growth curves of the summating potential (SP), the compound action potential (CAP) and the cochlear microphonics (CM) were detected after ADX. However, visually, there appeared to be a decrease of endolymphatic volume (tentatively called imdrops). Reissner's membrane (RM) extended less into scala vestibuli in ADX animals than in SHAM-operated animals. The ratio between the length of RM and the straight distance between the medial and lateral attachment points of RM were used as an objective measure to quantify this effect in each sub-apical half turn of the cochlea. The decrease in length of RM was statistically significant. Thus, circulating adrenal hormones appear to be necessary for normal cochlear fluid homeostasis. Absence of one or more of these hormones leads to shrinkage of the scala media (imdrops). However, the absence of adrenal hormones does not affect the gross cochlear potentials. Apparently, the cochlea is capable of compensating for the absence of circulating adrenal hormones to sustain the conditions necessary for proper cochlear transduction.

Psychometric validity of the Cochlear Implant Function Index (CIFI): a quality of life assessment tool for adult cochlear implant users.

PubMed

Coelho, Daniel H; Hammerschlag, Paul E; Bat-Chava, Yael; Kohan, Darius

2009-06-01

The Cochlear Implant Function Index (CIFI) is created to assess adult cochlear implant (CI) auditory effectiveness in real world situations. Our objective is to evaluate the CIFI as a reliable psychometric tool to assess 1) reliance on visual assistance, 2) telephone use, 3) communication at work, 4) 'hearing' in noise, 5) in groups, and 6) in large room settings. Based upon Guttman scaling properties, the CIFI elicits implanted respondent's functional level with auditory independence from Level 1 (still requiring signing) to level 4 (without any help beyond CI). A blinded, retrospective questionnaire is anonymously answered by cochlear implant recipients. CI centers of tertiary care medical centers, CI support group, and an interactive web page of a hearing and speech center in a large metropolitan region. 245 respondents from a varied adult CI population implanted for one month to 19 years prior to answering the questionnaire. An assessment tool of CI function. A coefficient of reproducibility (CR) for the Guttman scale format equal or greater than 0.90, indicating good scalability. CR in the CIFI was above 0.90. Effective scalability and mean scores from 2.5 to 3.5 for the six areas examined (1.00-4.00) were achieved. The psychometric properties of this user friendly survey demonstrate consistently good scalability. Based on these findings, the CIFI provides a validated tool that can be used for systematic comparisons between groups of patients or for follow-up outcomes in patients who use cochlear implants. Further study is indicated to correlate CIFI scores with sound and speech perception scores. Copyright 2009 John Wiley & Sons, Ltd.

Comparison of memory and meta-memory abilities of children with cochlear implant and normal hearing peers.

PubMed

Engel-Yeger, Batya; Durr, Doris H; Josman, Naomi

2011-01-01

This study aimed (1) to compare visual memory and meta-memory abilities, including the use of strategies as context, of children with cochlear implant (CI) and children with normal hearing; (2) to examine the concurrent and construct validity of 'The Contextual Memory Test for Children' (CMT-CH). Twenty children with CI and 20 children with normal hearing, aged 8-10 years, participated in this study. Memory abilities were measured by two subtests of the Children's Memory Scale (CMS) and by CMT-CH, which also measures meta-memory abilities. Children with CI scored significantly lower in both tests of memory and meta-memory and showed less efficient use of context to memorise. Significant positive correlations were found between CMS and CMT-CH memory tests in both groups. Visual memory and meta-memory abilities may be impaired in children with CI. Evaluation and intervention for children with CI should refer to their memory and meta-memory abilities in order to measure the outcomes of CIs, and enhance language development academic achievements. Although more studies on CMT-CH should be performed, the CMT-CH may be used for the evaluation of visual memory of children with CI.

Identification and Treatment of Very Young Children with Hearing Loss.

ERIC Educational Resources Information Center

Madell, Jane R.

1988-01-01

Hearing loss in infants and young children can be identified through behavioral observation audiometry, visual reinforcement audiometry, or auditory brainstem response testing. Habilitation may involve amplification with hearing aids, other assistive listening devices, or cochlear implants. Expectations for children with different degrees of…

Short-Term and Working Memory Impairments in Early-Implanted, Long-Term Cochlear Implant Users Are Independent of Audibility and Speech Production

PubMed Central

AuBuchon, Angela M.; Pisoni, David B.; Kronenberger, William G.

2015-01-01

OBJECTIVES Determine if early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. DESIGN Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions which differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). RESULTS Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. CONCLUSIONS Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory utilizing phonological and linguistic strategies during memory tasks. PMID:26496666

Short-Term and Working Memory Impairments in Early-Implanted, Long-Term Cochlear Implant Users Are Independent of Audibility and Speech Production.

PubMed

AuBuchon, Angela M; Pisoni, David B; Kronenberger, William G

2015-01-01

To determine whether early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions that differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory using phonological and linguistic strategies during memory tasks.

Validating a Method to Assess Lipreading, Audiovisual Gain, and Integration During Speech Reception With Cochlear-Implanted and Normal-Hearing Subjects Using a Talking Head.

PubMed

Schreitmüller, Stefan; Frenken, Miriam; Bentz, Lüder; Ortmann, Magdalene; Walger, Martin; Meister, Hartmut

Watching a talker's mouth is beneficial for speech reception (SR) in many communication settings, especially in noise and when hearing is impaired. Measures for audiovisual (AV) SR can be valuable in the framework of diagnosing or treating hearing disorders. This study addresses the lack of standardized methods in many languages for assessing lipreading, AV gain, and integration. A new method is validated that supplements a German speech audiometric test with visualizations of the synthetic articulation of an avatar that was used, for it is feasible to lip-sync auditory speech in a highly standardized way. Three hypotheses were formed according to the literature on AV SR that used live or filmed talkers. It was tested whether respective effects could be reproduced with synthetic articulation: (1) cochlear implant (CI) users have a higher visual-only SR than normal-hearing (NH) individuals, and younger individuals obtain higher lipreading scores than older persons. (2) Both CI and NH gain from presenting AV over unimodal (auditory or visual) sentences in noise. (3) Both CI and NH listeners efficiently integrate complementary auditory and visual speech features. In a controlled, cross-sectional study with 14 experienced CI users (mean age 47.4) and 14 NH individuals (mean age 46.3, similar broad age distribution), lipreading, AV gain, and integration of a German matrix sentence test were assessed. Visual speech stimuli were synthesized by the articulation of the Talking Head system "MASSY" (Modular Audiovisual Speech Synthesizer), which displayed standardized articulation with respect to the visibility of German phones. In line with the hypotheses and previous literature, CI users had a higher mean visual-only SR than NH individuals (CI, 38%; NH, 12%; p < 0.001). Age was correlated with lipreading such that within each group, younger individuals obtained higher visual-only scores than older persons (rCI = -0.54; p = 0.046; rNH = -0.78; p < 0.001). Both CI and NH benefitted by AV over unimodal speech as indexed by calculations of the measures visual enhancement and auditory enhancement (each p < 0.001). Both groups efficiently integrated complementary auditory and visual speech features as indexed by calculations of the measure integration enhancement (each p < 0.005). Given the good agreement between results from literature and the outcome of supplementing an existing validated auditory test with synthetic visual cues, the introduced method can be considered an interesting candidate for clinical and scientific applications to assess measures important for AV SR in a standardized manner. This could be beneficial for optimizing the diagnosis and treatment of individual listening and communication disorders, such as cochlear implantation.

Cross-modal reorganization in cochlear implant users: Auditory cortex contributes to visual face processing.

PubMed

Stropahl, Maren; Plotz, Karsten; Schönfeld, Rüdiger; Lenarz, Thomas; Sandmann, Pascale; Yovel, Galit; De Vos, Maarten; Debener, Stefan

2015-11-01

There is converging evidence that the auditory cortex takes over visual functions during a period of auditory deprivation. A residual pattern of cross-modal take-over may prevent the auditory cortex to adapt to restored sensory input as delivered by a cochlear implant (CI) and limit speech intelligibility with a CI. The aim of the present study was to investigate whether visual face processing in CI users activates auditory cortex and whether this has adaptive or maladaptive consequences. High-density electroencephalogram data were recorded from CI users (n=21) and age-matched normal hearing controls (n=21) performing a face versus house discrimination task. Lip reading and face recognition abilities were measured as well as speech intelligibility. Evaluation of event-related potential (ERP) topographies revealed significant group differences over occipito-temporal scalp regions. Distributed source analysis identified significantly higher activation in the right auditory cortex for CI users compared to NH controls, confirming visual take-over. Lip reading skills were significantly enhanced in the CI group and appeared to be particularly better after a longer duration of deafness, while face recognition was not significantly different between groups. However, auditory cortex activation in CI users was positively related to face recognition abilities. Our results confirm a cross-modal reorganization for ecologically valid visual stimuli in CI users. Furthermore, they suggest that residual takeover, which can persist even after adaptation to a CI is not necessarily maladaptive. Copyright © 2015 Elsevier Inc. All rights reserved.

Visual Processing Recruits the Auditory Cortices in Prelingually Deaf Children and Influences Cochlear Implant Outcomes.

PubMed

Liang, Maojin; Chen, Yuebo; Zhao, Fei; Zhang, Junpeng; Liu, Jiahao; Zhang, Xueyuan; Cai, Yuexin; Chen, Suijun; Li, Xianghui; Chen, Ling; Zheng, Yiqing

2017-09-01

Although visual processing recruitment of the auditory cortices has been reported previously in prelingually deaf children who have a rapidly developing brain and no auditory processing, the visual processing recruitment of auditory cortices might be different in processing different visual stimuli and may affect cochlear implant (CI) outcomes. Ten prelingually deaf children, 4 to 6 years old, were recruited for the study. Twenty prelingually deaf subjects, 4 to 6 years old with CIs for 1 year, were also recruited; 10 with well-performing CIs, 10 with poorly performing CIs. Ten age and sex-matched normal-hearing children were recruited as controls. Visual ("sound" photo [photograph with imaginative sound] and "nonsound" photo [photograph without imaginative sound]) evoked potentials were measured in all subjects. P1 at Oz and N1 at the bilateral temporal-frontal areas (FC3 and FC4) were compared. N1 amplitudes were strongest in the deaf children, followed by those with poorly performing CIs, controls and those with well-performing CIs. There was no significant difference between controls and those with well-performing CIs. "Sound" photo stimuli evoked a stronger N1 than "nonsound" photo stimuli. Further analysis showed that only at FC4 in deaf subjects and those with poorly performing CIs were the N1 responses to "sound" photo stimuli stronger than those to "nonsound" photo stimuli. No significant difference was found for the FC3 and FC4 areas. No significant difference was found in N1 latencies and P1 amplitudes or latencies. The results indicate enhanced visual recruitment of the auditory cortices in prelingually deaf children. Additionally, the decrement in visual recruitment of auditory cortices was related to good CI outcomes.

Preparation for the Implantation of an Intracortical Visual Prosthesis in a Human

DTIC Science & Technology

2015-12-01

cluster of the WFMA. Electrode current flows between the micro-(working) electrode and a longer large-area counter electrode, using either...Biomed Eng 44(10):931-9. McCreery DB, Yuen TGH, Agnew, WF, Bullara LA (2000). Chronic microstimulation in the feline ventral cochlear nucleus

Determining electrically evoked compound action potential thresholds: a comparison of computer versus human analysis methods.

PubMed

Glassman, E Katelyn; Hughes, Michelle L

2013-01-01

Current cochlear implants (CIs) have telemetry capabilities for measuring the electrically evoked compound action potential (ECAP). Neural Response Telemetry (Cochlear) and Neural Response Imaging (Advanced Bionics [AB]) can measure ECAP responses across a range of stimulus levels to obtain an amplitude growth function. Software-specific algorithms automatically mark the leading negative peak, N1, and the following positive peak/plateau, P2, and apply linear regression to estimate ECAP threshold. Alternatively, clinicians may apply expert judgments to modify the peak markers placed by the software algorithms, or use visual detection to identify the lowest level yielding a measurable ECAP response. The goals of this study were to: (1) assess the variability between human and computer decisions for (a) marking N1 and P2 and (b) determining linear-regression threshold (LRT) and visual-detection threshold (VDT); and (2) compare LRT and VDT methods within and across human- and computer-decision methods. ECAP amplitude-growth functions were measured for three electrodes in each of 20 ears (10 Cochlear Nucleus® 24RE/CI512, and 10 AB CII/90K). LRT, defined as the current level yielding an ECAP with zero amplitude, was calculated for both computer- (C-LRT) and human-picked peaks (H-LRT). VDT, defined as the lowest level resulting in a measurable ECAP response, was also calculated for both computer- (C-VDT) and human-picked peaks (H-VDT). Because Neural Response Imaging assigns peak markers to all waveforms but does not include waveforms with amplitudes less than 20 μV in its regression calculation, C-VDT for AB subjects was defined as the lowest current level yielding an amplitude of 20 μV or more. Overall, there were significant correlations between human and computer decisions for peak-marker placement, LRT, and VDT for both manufacturers (r = 0.78-1.00, p < 0.001). For Cochlear devices, LRT and VDT correlated equally well for both computer- and human-picked peaks (r = 0.98-0.99, p < 0.001), which likely reflects the well-defined Neural Response Telemetry algorithm and the lower noise floor in the 24RE and CI512 devices. For AB devices, correlations between LRT and VDT for both peak-picker methods were weaker than for Cochlear devices (r = 0.69-0.85, p < 0.001), which likely reflect the higher noise floor of the system. Disagreement between computer and human decisions regarding the presence of an ECAP response occurred for 5 % of traces for Cochlear devices and 2.1 % of traces for AB devices. Results indicate that human and computer peak-picking methods can be used with similar accuracy for both Cochlear and AB devices. Either C-VDT or C-LRT can be used with equal confidence for Cochlear 24RE and CI512 recipients because both methods are strongly correlated with human decisions. However, for AB devices, greater variability exists between different threshold-determination methods. This finding should be considered in the context of using ECAP measures to assist with programming CIs.

Monitoring blood-flow in the mouse cochlea using an endoscopic laser speckle contrast imaging system

PubMed Central

Yu, Sunkon; Jung, Byungjo; Choi, Jin Sil

2018-01-01

Laser speckle contrast imaging (LSCI) enables continuous high-resolution assessment of microcirculation in real-time. We applied an endoscope to LSCI to measure cochlear blood-flow in an ischemia–reperfusion mouse model. We also explored whether using xenon light in combination with LSCI facilitates visualization of anatomical position. Based on a previous preliminary study, the appropriate wavelength for penetrating the thin bony cochlea was 830 nm. A 2.7-mm-diameter endoscope was used, as appropriate for the size of the mouse cochlea. Our endoscopic LSCI system was used to illuminate the right cochlea after dissection of the mouse. We observed changes in the speckle signals when we applied the endoscopic LSCI system to the ischemia-reperfusion mouse model. The anatomical structure of the mouse cochlea and surrounding structures were clearly visible using the xenon light. The speckle signal of the cochlea was scattered, with an intensity that varied between that of the stapes (with the lowest signal), the negative control, and the stapedial artery (with the highest signal), the positive control. In the cochlear ischemia–reperfusion mouse model, the speckle signal of the cochlea decreased during the ischemic phase, and increased during the reperfusion phase, clearly reflecting cochlear blood-flow. The endoscopic LSCI system generates high-resolution images in real-time, allowing visualization of blood-flow and its changes in the mouse cochlea. Anatomical structures were clearly matched using LSCI along with visible light. PMID:29489849

Monitoring blood-flow in the mouse cochlea using an endoscopic laser speckle contrast imaging system.

PubMed

Kong, Tae Hoon; Yu, Sunkon; Jung, Byungjo; Choi, Jin Sil; Seo, Young Joon

2018-01-01

Laser speckle contrast imaging (LSCI) enables continuous high-resolution assessment of microcirculation in real-time. We applied an endoscope to LSCI to measure cochlear blood-flow in an ischemia-reperfusion mouse model. We also explored whether using xenon light in combination with LSCI facilitates visualization of anatomical position. Based on a previous preliminary study, the appropriate wavelength for penetrating the thin bony cochlea was 830 nm. A 2.7-mm-diameter endoscope was used, as appropriate for the size of the mouse cochlea. Our endoscopic LSCI system was used to illuminate the right cochlea after dissection of the mouse. We observed changes in the speckle signals when we applied the endoscopic LSCI system to the ischemia-reperfusion mouse model. The anatomical structure of the mouse cochlea and surrounding structures were clearly visible using the xenon light. The speckle signal of the cochlea was scattered, with an intensity that varied between that of the stapes (with the lowest signal), the negative control, and the stapedial artery (with the highest signal), the positive control. In the cochlear ischemia-reperfusion mouse model, the speckle signal of the cochlea decreased during the ischemic phase, and increased during the reperfusion phase, clearly reflecting cochlear blood-flow. The endoscopic LSCI system generates high-resolution images in real-time, allowing visualization of blood-flow and its changes in the mouse cochlea. Anatomical structures were clearly matched using LSCI along with visible light.

Nonverbal Cognitive Development in Children With Cochlear Implants: Relationship Between the Mullen Scales of Early Learning and Later Performance on the Leiter International Performance Scales–Revised

PubMed Central

Caudle, Susan E.; Katzenstein, Jennifer M.; Oghalai, John S.; Lin, Jerry; Caudle, Donald D.

2013-01-01

Methodologically, longitudinal assessment of cognitive development in young children has proven difficult because few measures span infancy through school age. This matter is further complicated when the child presents with a sensory deficit such as hearing loss. Few measures are validated in this population, and children who are evaluated for cochlear implantation are often reevaluated annually. The authors sought to evaluate the predictive validity of subscales of the Mullen Scales of Early Learning (MSEL) on Leiter International Performance Scales–Revised (LIPS-R) Full-Scale IQ scores. To further elucidate the relationship of these two measures, comparisons were also made with the Vineland Adaptive Behavior Scale–Second Edition (VABS), which provides a measure of adaptive functioning across the life span. Participants included 35 children (14 female, 21 male) who were evaluated both as part of the precandidacy process for cochlear implantation using the MSEL and VABS and following implantation with the LIPS-R and VABS. Hierarchical linear regression revealed that the MSEL Visual Reception subdomain score significantly predicted 52% of the variance in LIPS-R Full-Scale IQ scores at follow-up, F(1, 34) = 35.80, p < .0001, R2 = .52, β = .72. This result suggests that the Visual Reception subscale offers predictive validity of later LIPS-R Full-Scale IQ scores. The VABS was also significantly correlated with cognitive variables at each time point. PMID:22353228

Nonverbal cognitive development in children with cochlear implants: relationship between the Mullen Scales of Early Learning and later performance on the Leiter International Performance Scales-Revised.

PubMed

Caudle, Susan E; Katzenstein, Jennifer M; Oghalai, John S; Lin, Jerry; Caudle, Donald D

2014-02-01

Methodologically, longitudinal assessment of cognitive development in young children has proven difficult because few measures span infancy through school age. This matter is further complicated when the child presents with a sensory deficit such as hearing loss. Few measures are validated in this population, and children who are evaluated for cochlear implantation are often reevaluated annually. The authors sought to evaluate the predictive validity of subscales of the Mullen Scales of Early Learning (MSEL) on Leiter International Performance Scales-Revised (LIPS-R) Full-Scale IQ scores. To further elucidate the relationship of these two measures, comparisons were also made with the Vineland Adaptive Behavior Scale-Second Edition (VABS), which provides a measure of adaptive functioning across the life span. Participants included 35 children (14 female, 21 male) who were evaluated both as part of the precandidacy process for cochlear implantation using the MSEL and VABS and following implantation with the LIPS-R and VABS. Hierarchical linear regression revealed that the MSEL Visual Reception subdomain score significantly predicted 52% of the variance in LIPS-R Full-Scale IQ scores at follow-up, F(1, 34) = 35.80, p < .0001, R (2) = .52, β = .72. This result suggests that the Visual Reception subscale offers predictive validity of later LIPS-R Full-Scale IQ scores. The VABS was also significantly correlated with cognitive variables at each time point.

Toward the development of a cortically based visual neuroprosthesis.

PubMed

Normann, Richard A; Greger, Bradley; Greger, Bradley A; House, Paul; Romero, Samuel F; Pelayo, Francisco; Fernandez, Eduardo

2009-06-01

Motivated by the success of cochlear implants for deaf patients, we are now facing the goal of creating a visual neuroprosthesis designed to interface with the occipital cortex as a means through which a limited but useful sense of vision could be restored in profoundly blind patients. We review the most important challenges regarding this neuroprosthetic approach and emphasize the need for basic human psychophysical research on the best way of presenting complex stimulating patterns through multiple microelectrodes. Continued research will hopefully lead to the development of and design specifications for the first generation of a cortically based visual prosthesis system.

PERSPECTIVE: Toward the development of a cortically based visual neuroprosthesis

NASA Astrophysics Data System (ADS)

Normann, Richard A.; Greger, Bradley A.; House, Paul; Romero, Samuel F.; Pelayo, Francisco; Fernandez, Eduardo

2009-06-01

Motivated by the success of cochlear implants for deaf patients, we are now facing the goal of creating a visual neuroprosthesis designed to interface with the occipital cortex as a means through which a limited but useful sense of vision could be restored in profoundly blind patients. We review the most important challenges regarding this neuroprosthetic approach and emphasize the need for basic human psychophysical research on the best way of presenting complex stimulating patterns through multiple microelectrodes. Continued research will hopefully lead to the development of and design specifications for the first generation of a cortically based visual prosthesis system.

Cortical reorganization in postlingually deaf cochlear implant users: Intra-modal and cross-modal considerations.

PubMed

Stropahl, Maren; Chen, Ling-Chia; Debener, Stefan

2017-01-01

With the advances of cochlear implant (CI) technology, many deaf individuals can partially regain their hearing ability. However, there is a large variation in the level of recovery. Cortical changes induced by hearing deprivation and restoration with CIs have been thought to contribute to this variation. The current review aims to identify these cortical changes in postlingually deaf CI users and discusses their maladaptive or adaptive relationship to the CI outcome. Overall, intra-modal and cross-modal reorganization patterns have been identified in postlingually deaf CI users in visual and in auditory cortex. Even though cross-modal activation in auditory cortex is considered as maladaptive for speech recovery in CI users, a similar activation relates positively to lip reading skills. Furthermore, cross-modal activation of the visual cortex seems to be adaptive for speech recognition. Currently available evidence points to an involvement of further brain areas and suggests that a focus on the reversal of visual take-over of the auditory cortex may be too limited. Future investigations should consider expanded cortical as well as multi-sensory processing and capture different hierarchical processing steps. Furthermore, prospective longitudinal designs are needed to track the dynamics of cortical plasticity that takes place before and after implantation. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Speech perception skills of deaf infants following cochlear implantation: a first report

PubMed Central

Houston, Derek M.; Pisoni, David B.; Kirk, Karen Iler; Ying, Elizabeth A.; Miyamoto, Richard T.

2012-01-01

Summary Objective We adapted a behavioral procedure that has been used extensively with normal-hearing (NH) infants, the visual habituation (VH) procedure, to assess deaf infants’ discrimination and attention to speech. Methods Twenty-four NH 6-month-olds, 24 NH 9-month-olds, and 16 deaf infants at various ages before and following cochlear implantation (CI) were tested in a sound booth on their caregiver’s lap in front of a TV monitor. During the habituation phase, each infant was presented with a repeating speech sound (e.g. ‘hop hop hop’) paired with a visual display of a checkerboard pattern on half of the trials (‘sound trials’) and only the visual display on the other half (‘silent trials’). When the infant’s looking time decreased and reached a habituation criterion, a test phase began. This consisted of two trials: an ‘old trial’ that was identical to the ‘sound trials’ and a ‘novel trial’ that consisted of a different repeating speech sound (e.g. ‘ahhh’) paired with the same checkerboard pattern. Results During the habituation phase, NH infants looked significantly longer during the sound trials than during the silent trials. However, deaf infants who had received cochlear implants (CIs) displayed a much weaker preference for the sound trials. On the other hand, both NH infants and deaf infants with CIs attended significantly longer to the visual display during the novel trial than during the old trial, suggesting that they were able to discriminate the speech patterns. Before receiving CIs, deaf infants did not show any preferences. Conclusions Taken together, the findings suggest that deaf infants who receive CIs are able to detect and discriminate some speech patterns. However, their overall attention to speech sounds may be less than NH infants’. Attention to speech may impact other aspects of speech perception and spoken language development, such as segmenting words from fluent speech and learning novel words. Implications of the effects of early auditory deprivation and age at CI on speech perception and language development are discussed. PMID:12697350

Advances Underlying Spoken Language Development: A Century of Building on Bell.

ERIC Educational Resources Information Center

Ling, Daniel

1990-01-01

This article compares Alexander Graham Bell's achievements in the areas of instruction and technology for the hearing impaired with contemporary techniques and devices, many of which stem from his work. Assessment techniques, cochlear implants, tactile devices and visual aids are discussed as well as other alternatives and supplements to residual…

Perceptual “vowel spaces” of cochlear implant users: Implications for the study of auditory adaptation to spectral shift

PubMed Central

Harnsberger, James D.; Svirsky, Mario A.; Kaiser, Adam R.; Pisoni, David B.; Wright, Richard; Meyer, Ted A.

2012-01-01

Cochlear implant (CI) users differ in their ability to perceive and recognize speech sounds. Two possible reasons for such individual differences may lie in their ability to discriminate formant frequencies or to adapt to the spectrally shifted information presented by cochlear implants, a basalward shift related to the implant’s depth of insertion in the cochlea. In the present study, we examined these two alternatives using a method-of-adjustment (MOA) procedure with 330 synthetic vowel stimuli varying in F1 and F2 that were arranged in a two-dimensional grid. Subjects were asked to label the synthetic stimuli that matched ten monophthongal vowels in visually presented words. Subjects then provided goodness ratings for the stimuli they had chosen. The subjects’ responses to all ten vowels were used to construct individual perceptual “vowel spaces.” If CI users fail to adapt completely to the basalward spectral shift, then the formant frequencies of their vowel categories should be shifted lower in both F1 and F2. However, with one exception, no systematic shifts were observed in the vowel spaces of CI users. Instead, the vowel spaces differed from one another in the relative size of their vowel categories. The results suggest that differences in formant frequency discrimination may account for the individual differences in vowel perception observed in cochlear implant users. PMID:11386565

Oscillatory flow in the cochlea visualized by a magnetic resonance imaging technique.

PubMed

Denk, W; Keolian, R M; Ogawa, S; Jelinski, L W

1993-02-15

We report a magnetic resonance imaging technique that directly measures motion of cochlear fluids. It uses oscillating magnetic field gradients phase-locked to an external stimulus to selectively visualize and quantify oscillatory fluid motion. It is not invasive, and it does not require optical line-of-sight access to the inner ear. It permits the detection of displacements far smaller than the spatial resolution. The method is demonstrated on a phantom and on living rats. It is projected to have applications for auditory research, for the visualization of vocal tract dynamics during speech and singing, and for determination of the spatial distribution of mechanical relaxations in materials.

Lamb Temporal Bone as a Surgical Training Model of Round Window Cochlear Implant Electrode Insertion.

PubMed

Mantokoudis, Georgios; Huth, Markus E; Weisstanner, Christian; Friedrich, Hergen M; Nauer, Claude; Candreia, Claudia; Caversaccio, Marco D; Senn, Pascal

2016-01-01

The preservation of residual hearing in cochlear implantation opens the door for optimal functional results. This atraumatic surgical technique requires training; however, the traditional human cadaveric temporal bones have become less available or unattainable in some institutions. This study investigates the suitability of an alternative model, using cadaveric lamb temporal bone, for surgical training of atraumatic round window electrode insertion. A total of 14 lamb temporal bones were dissected for cochlear implantation by four surgeons. After mastoidectomy, visualization, and drilling of the round window niche, an atraumatic round window insertion of a Medel Flex24 electrode was performed. Electrode insertion depth and position were verified by computed tomography scans. All cochleas were successfully implanted using the atraumatic round window approach; however, surgical access through the mastoid was substantially different when compared human anatomy. The mean number of intracochlear electrode contacts was 6.5 (range, 4-11) and the mean insertion depth 10.4 mm (range, 4-20 mm), which corresponds to a mean angular perimodiolar insertion depth of 229 degrees (range 67-540°). Full insertion of the electrode was not possible because of the smaller size of the lamb cochlea in comparison to that of the human. The lamb temporal bone model is well suited as a training model for atraumatic cochlear implantation at the level of the round window. The minimally pneumatized mastoid as well as the smaller cochlea can help prepare a surgeon for difficult cochlear implantations. Because of substantial differences to human anatomy, it is not an adequate training model for other surgical techniques such as mastoidectomy and posterior tympanotomy as well as full electrode insertion.

Stimulation from Cochlear Implant Electrodes Assists with Recovery from Asymmetric Perceptual Tilt: Evidence from the Subjective Visual Vertical Test

PubMed Central

Gnanasegaram, Joshua J.; Parkes, William J.; Cushing, Sharon L.; McKnight, Carmen L.; Papsin, Blake C.; Gordon, Karen A.

2016-01-01

Vestibular end organ impairment is highly prevalent in children who have sensorineural hearing loss (SNHL) rehabilitated with cochlear implants (CIs). As a result, spatial perception is likely to be impacted in this population. Of particular interest is the perception of visual vertical because it reflects a perceptual tilt in the roll axis and is sensitive to an imbalance in otolith function. The objectives of the present study were thus to identify abnormalities in perception of the vertical plane in children with SNHL and determine whether such abnormalities could be resolved with stimulation from the CI. Participants included 53 children (15.2 ± 4.0 years of age) with SNHL and vestibular loss, confirmed with vestibular evoked myogenic potential (VEMP) testing. Testing protocol was validated in a sample of nine young adults with normal hearing (28.8 ± 7.7 years). Perception of visual vertical was assessed using the static Subjective Visual Vertical (SVV) test performed with and without stimulation in the participants with cochleovestibular loss. Trains of electrical pulses were delivered by an electrode in the left and/or right ear. Asymmetric spatial orientation deficits were found in nearly half of the participants with CIs (24/53 [45%]). The abnormal perception in this cohort was exacerbated by visual tilts in the direction of their deficit. Electric pulse trains delivered using the CI shifted this abnormal perception towards center (i.e., normal; p = 0.007). Importantly, this benefit was realized regardless of which ear was stimulated. These results suggest a role for CI stimulation beyond the auditory system, in particular, for improving vestibular/balance function. PMID:27679562

Cognitive Compensation of Speech Perception With Hearing Impairment, Cochlear Implants, and Aging

PubMed Central

Clarke, Jeanne; Pals, Carina; Benard, Michel R.; Bhargava, Pranesh; Saija, Jefta; Sarampalis, Anastasios; Wagner, Anita; Gaudrain, Etienne

2016-01-01

External degradations in incoming speech reduce understanding, and hearing impairment further compounds the problem. While cognitive mechanisms alleviate some of the difficulties, their effectiveness may change with age. In our research, reviewed here, we investigated cognitive compensation with hearing impairment, cochlear implants, and aging, via (a) phonemic restoration as a measure of top-down filling of missing speech, (b) listening effort and response times as a measure of increased cognitive processing, and (c) visual world paradigm and eye gazing as a measure of the use of context and its time course. Our results indicate that between speech degradations and their cognitive compensation, there is a fine balance that seems to vary greatly across individuals. Hearing impairment or inadequate hearing device settings may limit compensation benefits. Cochlear implants seem to allow the effective use of sentential context, but likely at the cost of delayed processing. Linguistic and lexical knowledge, which play an important role in compensation, may be successfully employed in advanced age, as some compensatory mechanisms seem to be preserved. These findings indicate that cognitive compensation in hearing impairment can be highly complicated—not always absent, but also not easily predicted by speech intelligibility tests only.

Cochlear implantation in children and adults in Switzerland.

PubMed

Brand, Yves; Senn, Pascal; Kompis, Martin; Dillier, Norbert; Allum, John H J

2014-02-04

The cochlear implant (CI) is one of the most successful neural prostheses developed to date. It offers artificial hearing to individuals with profound sensorineural hearing loss and with insufficient benefit from conventional hearing aids. The first implants available some 30 years ago provided a limited sensation of sound. The benefit for users of these early systems was mostly a facilitation of lip-reading based communication rather than an understanding of speech. Considerable progress has been made since then. Modern, multichannel implant systems feature complex speech processing strategies, high stimulation rates and multiple sites of stimulation in the cochlea. Equipped with such a state-of-the-art system, the majority of recipients today can communicate orally without visual cues and can even use the telephone. The impact of CIs on deaf individuals and on the deaf community has thus been exceptional. To date, more than 300,000 patients worldwide have received CIs. In Switzerland, the first implantation was performed in 1977 and, as of 2012, over 2,000 systems have been implanted with a current rate of around 150 CIs per year. The primary purpose of this article is to provide a contemporary overview of cochlear implantation, emphasising the situation in Switzerland.

Micromechanics in the Gerbil Hemicochlea

NASA Astrophysics Data System (ADS)

Richter, C.-P.; Dallos, P.

2003-02-01

Micromechanical events in the cochlea represent the combined motions of all elements that convey vibrations from the basilar membrane (BM) to the stereocilia bundles of the inner hair cells, the sensory receptors of the mammalian cochlea. Because of the difficulty of visualizing the organ of Corti (OC), experimental data on micromechanics are extremely limited. Available results represent motions viewed either from one focal plane or from the surface of a cochlear preparation. The present experiments examine cochlear micromechanics at audio frequencies by using the hemicochlea that permits the viewing of all structures in a cochlear cross-section. Stroboscopic illumination and video-flow techniques have been used to quantify the motion of selected elements. The movements at different locations revealed a tuned response across frequencies with the best frequency increasing from more basal to more apical locations. Furthermore, the vibrations showed rotational components, such as rotations around a pivot point: the inner pillar foot. Inner and outer pillar cells, inner and outer hair cells, Deiters' cells and parts of the BM move together and form a so-called "rotating wedge". The movements of Hensen's cells represent a mode of vibration different from that of the rest of the OC.

Detection of Enteric Viruses in Shellfish from the Norwegian Coast

PubMed Central

Myrmel, M.; Berg, E. M. M.; Rimstad, E.; Grinde, B.

2004-01-01

Common blue mussels (Mytilus edulis), horse mussels (Modiolus modiolus), and flat oysters (Ostrea edulis) obtained from various harvesting and commercial production sites along the Norwegian coast were screened for the presence of norovirus by a real-time reverse transcription (RT)-nested PCR assay and for possible indicators of fecal contamination, i.e., for F-specific RNA bacteriophages (F-RNA phages) by plaque assay and for human adenoviruses and human circoviruses by nested PCR assay. The aims were to obtain relevant information for assessing the risk of transmission of enteric viruses by shellfish and to investigate the potential of various indicator viruses in routine screening. Noroviruses were detected in 6.8% of the samples, and the indicators were detected in 23.8% (F-RNA phages), 18.6% (adenoviruses), and 8.0% (circoviruses) of the samples. A seasonal variation was observed, with the exception of circoviruses, with more positive samples in the winter. A positive correlation was found between F-RNA phages and noroviruses. However, F-RNA phages were present in only 43% of the norovirus-positive samples. The results show that mussels from the Norwegian coast can constitute a risk of infection with enteric viruses and that routine testing of samples may be justified. Advantages and disadvantages of various options for screening are discussed. PMID:15128518

A study of hearing function and histopathologic changes in the cochlea of the type 2 diabetes model Tsumura Suzuki obese diabetes mouse.

PubMed

Tsuda, Junko; Sugahara, Kazuma; Hori, Takeshi; Kanagawa, Eiju; Takaki, Eiichi; Fujimoto, Mitsuaki; Nakai, Akira; Yamashita, Hiroshi

2016-11-01

This study used Tsumura Suzuki Obese Diabetes (TSOD) mice as a spontaneous type 2 diabetes model and Tsumura Suzuki Non-obesity (TSNO) mice as controls to investigate factors involved in the onset of hearing impairment. Body weight, blood glucose levels, and auditory brainstem responses (ABRs) were measured. The cochleae were excised and evaluated histopathologically. The TSOD mice showed significant hyperglycemia at 2-7 months and severe obesity at 5-10 months; significantly elevated ABR thresholds at 8-10 months; and the capillary lumens in the cochlea stria vascularis were narrower in the TSOD mice than in the TSNO mice. At 17 months, India ink vascular staining of the TSOD mice's cochleae revealed decreased capillary density in the stria vascularis. The vascular area of capillaries in the stria vascularis and the vascular area were significantly smaller in TSOD mice. Histopathological analysis showed vessel wall thickening in the modiolus and narrowed capillaries in the stria vascularis, suggesting reduced blood flow to the inner ear. The diabetes mice model used in our study showed early age-associated hearing loss, and histopathology showed findings of vessel wall thickening in the modiolus, narrowing of capillaries in the stria vascularis, and chronically reduced blood flow in the cochlea.

Organ distribution and food safety aspects of cadmium and lead in great scallops, Pecten maximus L., and Horse Mussels, Modiolus modiolus L., from Norwegian waters.

PubMed

Julshamn, Kaare; Duinker, Arne; Frantzen, Sylvia; Torkildsen, Lise; Maage, Amund

2008-04-01

The purpose of the study was to determine the levels and organ distribution of the potentially harmful inorganic elements cadmium and lead in great scallops and horse mussels from unpolluted Norwegian waters. The scallops far exceeded the EU-limit for cadmium in bivalves when all soft tissues were analysed. When only muscle and gonad were included, however, the level of cadmium was acceptable, because cadmium accumulated in the digestive gland with a mean of 52 mg/kg ww (wet weight). In horse mussel, lead was the most problematic element and the concentration varied from 1.4 to 6.6 mg/kg ww with a mean of 3.7 mg/kg ww, exceeding the EU limit of 1.5 mg Pb/kg. The highest concentration of lead was found in the kidney with an average of 120 mg/kg ww and with a maximum value of 240 mg/kg ww. The kidney tissue accounted for approximately 94% of the lead burden in the horse mussel. In order to consume these bivalves, only muscle and gonad of great scallops should be used for consumption and the kidney of horse mussel should be removed prior to consumption.

Computing Support for Basic Research in Perception and Cognition

DTIC Science & Technology

1988-12-07

hearing aids and cochlear implants, this suggests that certain types of proposed coding schemes, specifically those employing periodicity tuning in...developing a computer model of the interaction of declarative and procedural knowledge in skill acquisition. In the Visual Psychophysics Laboratory... Psycholinguistics - Laboratory a computer model of text comprehension and recall has been constructed and several - experiments have been completed that verify basic

Early Sign Language Experience Goes along with an Increased Cross-Modal Gain for Affective Prosodic Recognition in Congenitally Deaf CI Users

ERIC Educational Resources Information Center

Fengler, Ineke; Delfau, Pia-Céline; Röder, Brigitte

2018-01-01

It is yet unclear whether congenitally deaf cochlear implant (CD CI) users' visual and multisensory emotion perception is influenced by their history in sign language acquisition. We hypothesized that early-signing CD CI users, relative to late-signing CD CI users and hearing, non-signing controls, show better facial expression recognition and…

Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression

PubMed Central

Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

2014-01-01

Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well as dual-tasking did not really improve the dynamic postural performance of the CI patients. We conclude that CI patients become strongly visual dependent mainly in challenging postural conditions, a result they have to be awarded of particularly when getting older. PMID:24474907

Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression.

PubMed

Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

2013-01-01

Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well as dual-tasking did not really improve the dynamic postural performance of the CI patients. We conclude that CI patients become strongly visual dependent mainly in challenging postural conditions, a result they have to be awarded of particularly when getting older.

Magnetic Resonance Imaging With Cochlear Implant Magnet in Place: Safety and Imaging Quality.

PubMed

Carlson, Matthew L; Neff, Brian A; Link, Michael J; Lane, John I; Watson, Robert E; McGee, Kiaran P; Bernstein, Matt A; Driscoll, Colin L W

2015-07-01

To evaluate the safety and image quality of 1.5-T MRI in patients with cochlear implants and retained internal magnets. Retrospective case series from 2012 to 2014. Single tertiary academic referral center. All cochlear implant recipients undergoing 1.5-T MRI without internal magnet removal. MRI after tight headwrap application. Patient tolerance, complications, and characteristics of imaging artifact. Nineteen ears underwent a total of 34 MRI scans. Two patients did not tolerate imaging with the headwrap in place and required magnet removal before rescanning. One subject experienced two separate episodes of polarity reversal in the same device from physical realignment (i.e., flipping) of the internal magnet requiring surgical repositioning. Three patients were discovered to have canting of the internal magnet after imaging. In all three cases, the magnet could be reseated by applying gentle firm pressure to the scalp until the magnet "popped" back into place. These patients continue to use their device without difficulty and have not required surgical replacement. In patients receiving head MRI, the ipsilateral internal auditory canal and cerebellopontine angle could be visualized without difficulty in 94% of cases. There were no episodes of cochlear implant device failure or soft tissue complications. Under controlled conditions, 1.5-T MRI can be successfully performed in most patients without the need for cochlear implant magnet removal. In nearly all cases, imaging artifact does not impede evaluation of the ipsilateral skull base. Patients should be counseled regarding the risk of internal magnet movement that may occur in up to 15% of cases, even with tight headwrap application. If internal magnet polarity reversal occurs, a trial of reversing the external magnet can be considered. If canting or mild displacement of the internal magnet occurs, an attempt at reseating can be made by applying gentle firm pressure to the scalp over the internal magnet. If conservative measures fail, the magnet should be surgically repositioned to minimize interruption of device use and to prevent scalp complications.

Auditory cross-modal reorganization in cochlear implant users indicates audio-visual integration.

PubMed

Stropahl, Maren; Debener, Stefan

2017-01-01

There is clear evidence for cross-modal cortical reorganization in the auditory system of post-lingually deafened cochlear implant (CI) users. A recent report suggests that moderate sensori-neural hearing loss is already sufficient to initiate corresponding cortical changes. To what extend these changes are deprivation-induced or related to sensory recovery is still debated. Moreover, the influence of cross-modal reorganization on CI benefit is also still unclear. While reorganization during deafness may impede speech recovery, reorganization also has beneficial influences on face recognition and lip-reading. As CI users were observed to show differences in multisensory integration, the question arises if cross-modal reorganization is related to audio-visual integration skills. The current electroencephalography study investigated cortical reorganization in experienced post-lingually deafened CI users ( n  = 18), untreated mild to moderately hearing impaired individuals (n = 18) and normal hearing controls ( n  = 17). Cross-modal activation of the auditory cortex by means of EEG source localization in response to human faces and audio-visual integration, quantified with the McGurk illusion, were measured. CI users revealed stronger cross-modal activations compared to age-matched normal hearing individuals. Furthermore, CI users showed a relationship between cross-modal activation and audio-visual integration strength. This may further support a beneficial relationship between cross-modal activation and daily-life communication skills that may not be fully captured by laboratory-based speech perception tests. Interestingly, hearing impaired individuals showed behavioral and neurophysiological results that were numerically between the other two groups, and they showed a moderate relationship between cross-modal activation and the degree of hearing loss. This further supports the notion that auditory deprivation evokes a reorganization of the auditory system even at early stages of hearing loss.

Three-Dimensional Imaging of the Mouse Organ of Corti Cytoarchitecture for Mechanical Modeling

NASA Astrophysics Data System (ADS)

Puria, Sunil; Hartman, Byron; Kim, Jichul; Oghalai, John S.; Ricci, Anthony J.; Liberman, M. Charles

2011-11-01

Cochlear models typically use continuous anatomical descriptions and homogenized parameters based on two-dimensional images for describing the organ of Corti. To produce refined models based more closely on the actual cochlear cytoarchitecture, three-dimensional morphometric parameters of key mechanical structures are required. Towards this goal, we developed and compared three different imaging methods: (1) A fixed cochlear whole-mount preparation using the fluorescent dye Cellmask®, which is a molecule taken up by cell membranes and clearly delineates Deiters' cells, outer hair cells, and the phalangeal process, imaged using confocal microscopy; (2) An in situ fixed preparation with hair cells labeled using anti-prestin and supporting structures labeled using phalloidin, imaged using two-photon microscopy; and (3) A membrane-tomato (mT) mouse with fluorescent proteins expressed in all cell membranes, which enables two-photon imaging of an in situ live preparation with excellent visualization of the organ of Corti. Morphometric parameters including lengths, diameters, and angles, were extracted from 3D cellular surface reconstructions of the resulting images. Preliminary results indicate that the length of the phalangeal processes decreases from the first (inner most) to third (outer most) row of outer hair cells, and that their length also likely varies from base to apex and across species.

Executive Functioning Skills in Preschool-Age Children With Cochlear Implants

PubMed Central

Beer, Jessica; Kronenberger, William G.; Castellanos, Irina; Colson, Bethany G.; Henning, Shirley C.; Pisoni, David B.

2014-01-01

Purpose The purpose of this study was to determine whether deficits in executive functioning (EF) in children with cochlear implants (CIs) emerge as early as the preschool years. Method Two groups of children ages 3 to 6 years participated in this cross-sectional study: 24 preschoolers who had CIs prior to 36 months of age and 21 preschoolers with normal hearing (NH). All were tested on normed measures of working memory, inhibition-concentration, and organization-integration. Parents completed a normed rating scale of problem behaviors related to EF. Comparisons of EF skills of children with CIs were made to peers with NH and to published nationally representative norms. Results Preschoolers with CIs showed significantly poorer performance on inhibition-concentration and working memory compared with peers with NH and with national norms. No group differences were found in visual memory or organization-integration. When data were controlled for language, differences in performance measures of EF remained, whereas differences in parent-reported problems with EF were no longer significant. Hearing history was generally unrelated to EF. Conclusions This is the first study to demonstrate that EF deficits found in older children with CIs begin to emerge as early as preschool years. The ability to detect these deficits early has important implications for early intervention and habilitation after cochlear implantation. PMID:24686747

Imaging of cochlear tissue with a grating interferometer and hard X-rays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richter, Claus-Peter; Shintani-Smith, Stephanie; Fishman, Andrew

This article addresses an important current development in medical and biological imaging: the possibility of imaging soft tissue at resolutions in the micron range using hard X-rays. Challenging environments, including the cochlea, require the imaging of soft tissue structure surrounded by bone. We demonstrate that cochlear soft tissue structures can be imaged with hard X-ray phase contrast. Furthermore, we show that only a thin slice of the tissue is required to introduce a large phase shift. It is likely that the phase contrast image of the soft tissue structures is sufficient to image the structures even if surrounded by bone.more » For the present set of experiments, structures with low-absorption contrast have been visualized using in-line phase contrast imaging and a grating interferometer. The experiments have been performed at the Advanced Photon Source at Argonne National Laboratories, a third generation source of synchrotron radiation. The source provides highly coherent X-ray radiation with high-photon flux (>10{sup 12} photons/s) at high-photon energies (5-70 keV). Radiographic and light microscopy images of the gerbil cochlear slice samples were compared. It has been determined that a 20-{micro}m thick tissue slice induces a phase shift between 1/3{pi} and 2/3{pi}.« less

Getting signals into the brain: visual prosthetics through thalamic microstimulation.

PubMed

Pezaris, John S; Eskandar, Emad N

2009-07-01

Common causes of blindness are diseases that affect the ocular structures, such as glaucoma, retinitis pigmentosa, and macular degeneration, rendering the eyes no longer sensitive to light. The visual pathway, however, as a predominantly central structure, is largely spared in these cases. It is thus widely thought that a device-based prosthetic approach to restoration of visual function will be effective and will enjoy similar success as cochlear implants have for restoration of auditory function. In this article the authors review the potential locations for stimulation electrode placement for visual prostheses, assessing the anatomical and functional advantages and disadvantages of each. Of particular interest to the neurosurgical community is placement of deep brain stimulating electrodes in thalamic structures that has shown substantial promise in an animal model. The theory of operation of visual prostheses is discussed, along with a review of the current state of knowledge. Finally, the visual prosthesis is proposed as a model for a general high-fidelity machine-brain interface.

Multi-decadal changes in the megabenthos of the Bay of Fundy: The effects of fishing

NASA Astrophysics Data System (ADS)

Kenchington, Ellen L.; Kenchington, Trevor J.; Henry, Lea-Anne; Fuller, Susanna; Gonzalez, Patricia

2007-10-01

Analysis of presence / absence records from two comparable megabenthic surveys of scallop grounds in the Bay of Fundy, Canada, in 1966-67 and 1997 showed profound change over three decades. There were no indications that any species were lost and the average number of taxa per station remained steady. However, spatial heterogeneities in the community were reduced and species composition changed significantly. Some taxa widespread in 1966-67 declined while others expanded, with frequencies of occurrence of individual taxa changing by up to 71%. The whelks Buccinum undatum and Colus spp., the bivalves Astarte spp. and Cyclocardia borealis, the toad crabs Hyas spp., the sea urchin Strongylocentrotus droebachiensis and the brittle stars (Ophiurida) showed particular increases. Corresponding declines were seen in the boring sponges Cliona spp., the horse mussel Modiolus modiolus, the scallop Chlamys islandica, the fan worm Pseudopotamilla reniformis and the stalked tunicate Boltenia ovifera. Replacement of attached, fragile, epifaunal, filter-feeding taxa by a combination of motile scavengers, motile filter-feeders and robust, burrowing filter-feeders suggests that the primary cause of the temporal change was physical impacts by fishing gear, even though trawling and scallop dragging in the area were neither intense nor new developments. Secondary causes of change may have included other ecosystem effects of fishing (supply of discards and bait), a mass mortality of scallops and a range expansion of a bryozoan ( Flustra foliacea).

Visualization of human inner ear anatomy with high-resolution MR imaging at 7T: initial clinical assessment.

PubMed

van der Jagt, M A; Brink, W M; Versluis, M J; Steens, S C A; Briaire, J J; Webb, A G; Frijns, J H M; Verbist, B M

2015-02-01

In many centers, MR imaging of the inner ear and auditory pathway performed on 1.5T or 3T systems is part of the preoperative work-up of cochlear implants. We investigated the applicability of clinical inner ear MR imaging at 7T and compared the visibility of inner ear structures and nerves within the internal auditory canal with images acquired at 3T. Thirteen patients with sensorineural hearing loss eligible for cochlear implantation underwent examinations on 3T and 7T scanners. Two experienced head and neck radiologists evaluated the 52 inner ear datasets. Twenty-four anatomic structures of the inner ear and 1 overall score for image quality were assessed by using a 4-point grading scale for the degree of visibility. The visibility of 11 of the 24 anatomic structures was rated higher on the 7T images. There was no significant difference in the visibility of 13 anatomic structures and the overall quality rating. A higher incidence of artifacts was observed in the 7T images. The gain in SNR at 7T yielded a more detailed visualization of many anatomic structures, especially delicate ones, despite the challenges accompanying MR imaging at a high magnetic field. © 2015 by American Journal of Neuroradiology.

Alternative path to hearing: photonic sonogram hearing aid

NASA Astrophysics Data System (ADS)

Hara, Elmer H.

2002-05-01

For those with total hearing loss, there are no direct remedies except for electronic (i.e. cochlear) implants. They are invasive and do not always function in a satisfactory manner. Although sign language opens the window to a rich culture but communication with the hearing world is hindered. Lip reading can bridge that gap but communication is not without some stress. Inability to detect possible life threatening situations outside the visual field also affects the quality of life for those without the ability to hear. If the hearing process is viewed from the point of system engineering, there is a sound source and air is the transmission medium to the ear. The hearing structure of the ear converts mechanical vibrations to electrical signals that are then transmitted through nerve paths to the section of the brain where sound signals are processed. In most cases of total hearing loss, the hearing structure of the ear is non-functional. A cochlear implant bypasses this hearing structure. It electronically converts sounds from the air into their frequency components and feeds them into transmission nerve paths to the brain as electrical signals. This system-engineering point of view suggests that other pathways to the brain might be explored. The following section considers the visual pathway.

Beneficial auditory and cognitive effects of auditory brainstem implantation in children.

PubMed

Colletti, Liliana

2007-09-01

This preliminary study demonstrates the development of hearing ability and shows that there is a significant improvement in some cognitive parameters related to selective visual/spatial attention and to fluid or multisensory reasoning, in children fitted with auditory brainstem implantation (ABI). The improvement in cognitive paramenters is due to several factors, among which there is certainly, as demonstrated in the literature on a cochlear implants (CIs), the activation of the auditory sensory canal, which was previously absent. The findings of the present study indicate that children with cochlear or cochlear nerve abnormalities with associated cognitive deficits should not be excluded from ABI implantation. The indications for ABI have been extended over the last 10 years to adults with non-tumoral (NT) cochlear or cochlear nerve abnormalities that cannot benefit from CI. We demonstrated that the ABI with surface electrodes may provide sufficient stimulation of the central auditory system in adults for open set speech recognition. These favourable results motivated us to extend ABI indications to children with profound hearing loss who were not candidates for a CI. This study investigated the performances of young deaf children undergoing ABI, in terms of their auditory perceptual development and their non-verbal cognitive abilities. In our department from 2000 to 2006, 24 children aged 14 months to 16 years received an ABI for different tumour and non-tumour diseases. Two children had NF2 tumours. Eighteen children had bilateral cochlear nerve aplasia. In this group, nine children had associated cochlear malformations, two had unilateral facial nerve agenesia and two had combined microtia, aural atresia and middle ear malformations. Four of these children had previously been fitted elsewhere with a CI with no auditory results. One child had bilateral incomplete cochlear partition (type II); one child, who had previously been fitted unsuccessfully elsewhere with a CI, had auditory neuropathy; one child showed total cochlear ossification bilaterally due to meningitis; and one child had profound hearing loss with cochlear fractures after a head injury. Twelve of these children had multiple associated psychomotor handicaps. The retrosigmoid approach was used in all children. Intraoperative electrical auditory brainstem responses (EABRs) and postoperative EABRs and electrical middle latency responses (EMLRs) were performed. Perceptual auditory abilities were evaluated with the Evaluation of Auditory Responses to Speech (EARS) battery - the Listening Progress Profile (LIP), the Meaningful Auditory Integration Scale (MAIS), the Meaningful Use of Speech Scale (MUSS) - and the Category of Auditory Performance (CAP). Cognitive evaluation was performed on seven children using the Leiter International Performance Scale - Revised (LIPS-R) test with the following subtests: Figure ground, Form completion, Sequential order and Repeated pattern. No postoperative complications were observed. All children consistently used their devices for >75% of waking hours and had environmental sound awareness and utterance of words and simple sentences. Their CAP scores ranged from 1 to 7 (average =4); with MAIS they scored 2-97.5% (average =38%); MUSS scores ranged from 5 to 100% (average =49%) and LIP scores from 5 to 100% (average =45%). Owing to associated disabilities, 12 children were given other therapies (e.g. physical therapy and counselling) in addition to speech and aural rehabilitation therapy. Scores for two of the four subtests of LIPS-R in this study increased significantly during the first year of auditory brainstem implant use in all seven children selected for cognitive evaluation.

Surgical considerations and safety of cochlear implantation in otitis media with effusion.

PubMed

Cevizci, Rasit; Dilci, Alper; Celenk, Fatih; Karamert, Recep; Bayazit, Yildirim

2018-06-01

To evaluate the effects of otitis media with effusion on surgical parameters, patient safety, perioperative and postoperative complications. Total 890 children who underwent cochlear implantation between 2006 and 2015 were included. The ages ranged from 12 months to 63 months (mean: 32 months). The patients were divided into two groups according to the presence or absence of otitis media with effusion; otitis media with effusion group and non-otitis media group. Of 890 children, 105 had otitis media with effusion prior to surgery. In non-otitis media with group, there were 785 children. The average duration of surgery was 60min (ranged from 28 to 75min) in non-otitis media group, and 90min (ranged from 50 to 135min) in otitis media with effusion group (p<0.05). Granulation tissue and edematous middle ear and mastoid mucosa were observed in all cases of otitis media with effusion during the surgery. There was no significant difference between the complications of groups with or without otitis media with effusion (p>0.05). In 5 of 105 patients, there was a ventilation tube inserted before cochlear implantation, which did not change the outcome of implantation. There is no need for surgical treatment for otitis media with effusion before implantation since otitis media with effusion does not increase the risks associated with cochlear implantation. Operation duration is longer in the presence of otitis media with effusion. However, otitis media with effusion leads to intraoperative difficulties like longer operation duration, bleeding, visualization of the round window membrane, cleansing the middle ear granulations as well as mastoid and petrous air cells. Copyright © 2017 Elsevier B.V. All rights reserved.

New Criteria of Indication and Selection of Patients to Cochlear Implant

PubMed Central

Sampaio, André L. L.; Araújo, Mercêdes F. S.; Oliveira, Carlos A. C. P.

2011-01-01

Numerous changes continue to occur in cochlear implant candidacy. In general, these have been accompanied by concomitant and satisfactory changes in surgical techniques. Together, this has advanced the utility and safety of cochlear implantation. Most devices are now approved for use in patients with severe to profound unilateral hearing loss rather then the prior requirement of a bilateral profound loss. Furthermore, studies have begun utilizing short electrode arrays for shallow insertion in patients with considerable low-frequency residual hearing. This technique will allow the recipient to continue to use acoustically amplified hearing for the low frequencies simultaneously with a cochlear implant for the high frequencies. The advances in design of, and indications for, cochlear implants have been matched by improvements in surgical techniques and decrease in complications. The resulting improvements in safety and efficacy have further encouraged the use of these devices. This paper will review the new concepts in the candidacy of cochlear implant. Medline data base was used to search articles dealing with the following topics: cochlear implant in younger children, cochlear implant and hearing preservation, cochlear implant for unilateral deafness and tinnitus, genetic hearing loss and cochlear implant, bilateral cochlear implant, neuropathy and cochlear implant and neural plasticity, and the selection of patients for cochlear implant. PMID:22013448

[Correlation of auditory-verbal skills in patients with cochlear implants and their evaluation in positone emission tomography (PET)].

PubMed

Łukaszewicz, Zuzanna; Soluch, Paweł; Niemczyk, Kazimierz; Lachowska, Magdalena

2010-06-01

An assumption was taken that in central nervous system (CNS) in patients above 15 years of age there are possible mechanisms of neuronal changes. Those changes allow for reconstruction or formation of natural activation pattern of appropriate brain structures responsible for auditory speech processing. The aim of the study was to observe if there are any dynamic functional changes in central nervous system and their correlation to the auditory-verbal skills of the patients. Nine right-handed patients between 15 and 36 years of age were examined, 6 females and 3 males. All of them were treated with cochlear implantation and are in frequent follow-up in the Department of Otolaryngology at the Medical University of Warsaw due to profound sensorineural hearing loss. In present study the patients were examined within 24 hours after the first fitting of the speech processor of the cochlear implant, and 1 and 2 years subsequently. Combination of performed examinations consisted of: positone emission tomography of the brain, and audiological tests including speech assessment. In the group of patients 4 were postlingually deaf, and 5 were prelinqually deaf. Postlingually deaf patients achieved great improvement of hearing and speech understanding. In their first PET examination very intensive activation of visual cortex V1 and V2 (BA17 and 18) was observed. There was no significant activation in the dominant (left) hemisphere of the brain. In PET examination performed 1 and 2 years after the cochlear implantation no more V1 and V2 activation region was observed. Instead particular regions of the left hemisphere got activated. In prelingually deaf patients no significant changes in central nervous system were noticeable neither in PET nor in speech assessment, although their hearing possibilities improved. Positive correlation was observed between the level of speech understanding, linguistic skills and the activation of appropriate areas of the left hemisphere of the brain in postlingually deaf patients treated with cochlear implants. No such correlation was noted in prelingualy patients treated with the same method.

Applied anatomy of round window and adjacent structures of tympanum related to cochlear implantation.

PubMed

Jain, Shraddha; Gaurkar, Sagar; Deshmukh, Prasad T; Khatri, Mohnish; Kalambe, Sanika; Lakhotia, Pooja; Chandravanshi, Deepshikha; Disawal, Ashish

2018-04-19

Various aspects of the round window anatomy and anatomy of posterior tympanum have relevant implications for designing cochlear implant electrodes and visualizing the round window through facial recess. Preoperative information about possible anatomical variations of the round window and its relationships to the adjacent neurovascular structures can help reduce complications in cochlear implant surgery. The present study was undertaken to assess the common variations in round window anatomy and the relationships to structures of the tympanum that may be relevant for cochlear implant surgery. Thirty-five normal wet human cadaveric temporal bones were studied by dissection for anatomy of round window and its relation to facial nerve, carotid canal, jugular fossa and other structures of posterior tympanum. The dissected bones were photographed by a digital camera of 18 megapixels, which were then imported to a computer to determine various parameters using ScopyDoc 8.0.0.22 version software, after proper calibration and at 1× magnification. When the round window niche is placed posteriorly and inferiorly, the distance between round window and vertical facial nerve decreases, whereas that with horizontal facial nerve increases. In such cases, the distance between oval window and round window also increases. Maximum height of the round window in our study ranged from 0.51-1.27mm (mean of 0.69±0.25mm). Maximum width of round window ranged from 0.51 to 2.04mm (mean of 1.16±0.47mm). Average minimum distance between round window and carotid canal was 3.71±0.88mm (range of 2.79-5.34mm) and that between round window and jugular fossa was 2.47±0.9mm (range of 1.24-4.3mm). The distances from the round window to the oval window and facial nerve are important parameters in identifying a difficult round window niche. Modification of the electrode may be a better option than drilling off the round window margins for insertion of cochlear implant electrodes. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Cochlear Implants.

ERIC Educational Resources Information Center

Clark, Catherine; Scott, Larry

This brochure explains what a cochlear implant is, lists the types of individuals with deafness who may be helped by a cochlear implant, describes the process of evaluating people for cochlear implants, discusses the surgical process for implanting the aid, traces the path of sound through the cochlear implant to the brain, notes the costs of…

Speech identification in noise: Contribution of temporal, spectral, and visual speech cues.

PubMed

Kim, Jeesun; Davis, Chris; Groot, Christopher

2009-12-01

This study investigated the degree to which two types of reduced auditory signals (cochlear implant simulations) and visual speech cues combined for speech identification. The auditory speech stimuli were filtered to have only amplitude envelope cues or both amplitude envelope and spectral cues and were presented with/without visual speech. In Experiment 1, IEEE sentences were presented in quiet and noise. For in-quiet presentation, speech identification was enhanced by the addition of both spectral and visual speech cues. Due to a ceiling effect, the degree to which these effects combined could not be determined. In noise, these facilitation effects were more marked and were additive. Experiment 2 examined consonant and vowel identification in the context of CVC or VCV syllables presented in noise. For consonants, both spectral and visual speech cues facilitated identification and these effects were additive. For vowels, the effect of combined cues was underadditive, with the effect of spectral cues reduced when presented with visual speech cues. Analysis indicated that without visual speech, spectral cues facilitated the transmission of place information and vowel height, whereas with visual speech, they facilitated lip rounding, with little impact on the transmission of place information.

Musical FAVORS: Reintroducing music to adult cochlear implant users.

PubMed

Plant, Geoff

2015-09-01

Music represents a considerable challenge for many adult users of cochlear implants (CIs). Around half of adult CI users report that they do not find music enjoyable, and, in some cases, despite enhanced speech perception skills, this leads to considerable frustration and disappointment for the CI user. This paper presents suggestions to improve the musical experiences of deafened adults with CIs. Interviews with a number of adult CI users revealed that there were a number of factors which could lead to enhanced music experiences. The acronym FAVORS (familiar music, auditory-visual access, open-mindedness, and simple arrangements) summarizes the factors that have been identified, which can help CI users in their early music listening experiences. Each of these factors is discussed in detail, along with suggestions for how they can be used in therapy sessions. The use of a group approach (music focus groups) is also discussed and an overview of the approach and exercises used is presented. The importance of live music experiences is also discussed.

Psychosocial Outcomes in Long-Term Cochlear Implant Users.

PubMed

Castellanos, Irina; Kronenberger, William G; Pisoni, David B

The objectives of this study were to investigate psychosocial outcomes in a sample of prelingually deaf, early-implanted children, adolescents, and young adults who are long-term cochlear implant (CI) users and to examine the extent to which language and executive functioning predict psychosocial outcomes. Psychosocial outcomes were measured using two well-validated, parent-completed checklists: the Behavior Assessment System for Children and the Conduct Hyperactive Attention Problem Oppositional Symptom. Neurocognitive skills were measured using gold standard, performance-based assessments of language and executive functioning. CI users were at greater risk for clinically significant deficits in areas related to attention, oppositional behavior, hyperactivity-impulsivity, and social-adaptive skills compared with their normal-hearing peers, although the majority of CI users scored within average ranges relative to Behavior Assessment System for Children norms. Regression analyses revealed that language, visual-spatial working memory, and inhibition-concentration skills predicted psychosocial outcomes. Findings suggest that underlying delays and deficits in language and executive functioning may place some CI users at a risk for difficulties in psychosocial adjustment.

[Inspecting the cochlear scala tympanic with flexible and semi-flexible micro-endoscope].

PubMed

Zhang, Daoxcing; Zhang, Yankun

2006-02-01

Flexible and semi-flexible micro-endoscopes were used in cochlear scala tympani inspection , to explore their application in inner ear examination. Fifteen profound hearing loss patients preparing for cochlear implant were included in this study. During the operation, micro-endoscopy was performed after opening the cochlear scala tympani. And 1 mm diameter semi-flexible micro-endoscope could go as deep as 9 mm into the cochlear scala tympani, while 0. 5 mm diameter flexible micro-endoscope could go as deep as 25 mm. The inspecting results were compared with video recording. Using 0.5 mm flexible micro-endoscope, we canould check cochlear scala tympani with depth range of 15-25 mm, but the video imaging was not clear enough to examine the microstructure in the cochlear. With 1 mm diameter semi-flexible micro-endoscope, we could reach 9 mm deep into the cochlear. During the examination, we found 3 cases with calcification deposit in osseous spiral lamina, l case with granulation tissue in the lateral wall of scala tympani, no abnormal findings in the other 11 cases. Inspecting the cochlear scala tympani with 0.5 mm flexible micro-endoscope, even though we can reach the second circuit of the cochlear, it is difficult to find the pathology in the cochlear because of the poor video imaging. With 1 mm semi-flexible micro-endoscope, we can identify the microstructure of the cochlear clearly and find the pathologic changes, but the inserting depth was limited to 9 mm with limitation to examine the whole cochlear.

What Does Music Sound Like for a Cochlear Implant User?

PubMed

Jiam, Nicole T; Caldwell, Meredith T; Limb, Charles J

2017-09-01

Cochlear implant research and product development over the past 40 years have been heavily focused on speech comprehension with little emphasis on music listening and enjoyment. The relatively little understanding of how music sounds in a cochlear implant user stands in stark contrast to the overall degree of importance the public places on music and quality of life. The purpose of this article is to describe what music sounds like to cochlear implant users, using a combination of existing research studies and listener descriptions. We examined the published literature on music perception in cochlear implant users, particularly postlingual cochlear implant users, with an emphasis on the primary elements of music and recorded music. Additionally, we administered an informal survey to cochlear implant users to gather first-hand descriptions of music listening experience and satisfaction from the cochlear implant population. Limitations in cochlear implant technology lead to a music listening experience that is significantly distorted compared with that of normal hearing listeners. On the basis of many studies and sources, we describe how music is frequently perceived as out-of-tune, dissonant, indistinct, emotionless, and weak in bass frequencies, especially for postlingual cochlear implant users-which may in part explain why music enjoyment and participation levels are lower after implantation. Additionally, cochlear implant users report difficulty in specific musical contexts based on factors including but not limited to genre, presence of lyrics, timbres (woodwinds, brass, instrument families), and complexity of the perceived music. Future research and cochlear implant development should target these areas as parameters for improvement in cochlear implant-mediated music perception.

Cross-Modal and Intra-Modal Characteristics of Visual Function and Speech Perception Performance in Postlingually Deafened, Cochlear Implant Users

PubMed Central

Kim, Min-Beom; Shim, Hyun-Yong; Jin, Sun Hwa; Kang, Soojin; Woo, Jihwan; Han, Jong Chul; Lee, Ji Young; Kim, Martha; Cho, Yang-Sun

2016-01-01

Evidence of visual-auditory cross-modal plasticity in deaf individuals has been widely reported. Superior visual abilities of deaf individuals have been shown to result in enhanced reactivity to visual events and/or enhanced peripheral spatial attention. The goal of this study was to investigate the association between visual-auditory cross-modal plasticity and speech perception in post-lingually deafened, adult cochlear implant (CI) users. Post-lingually deafened adults with CIs (N = 14) and a group of normal hearing, adult controls (N = 12) participated in this study. The CI participants were divided into a good performer group (good CI, N = 7) and a poor performer group (poor CI, N = 7) based on word recognition scores. Visual evoked potentials (VEP) were recorded from the temporal and occipital cortex to assess reactivity. Visual field (VF) testing was used to assess spatial attention and Goldmann perimetry measures were analyzed to identify differences across groups in the VF. The association of the amplitude of the P1 VEP response over the right temporal or occipital cortex among three groups (control, good CI, poor CI) was analyzed. In addition, the association between VF by different stimuli and word perception score was evaluated. The P1 VEP amplitude recorded from the right temporal cortex was larger in the group of poorly performing CI users than the group of good performers. The P1 amplitude recorded from electrodes near the occipital cortex was smaller for the poor performing group. P1 VEP amplitude in right temporal lobe was negatively correlated with speech perception outcomes for the CI participants (r = -0.736, P = 0.003). However, P1 VEP amplitude measures recorded from near the occipital cortex had a positive correlation with speech perception outcome in the CI participants (r = 0.775, P = 0.001). In VF analysis, CI users showed narrowed central VF (VF to low intensity stimuli). However, their far peripheral VF (VF to high intensity stimuli) was not different from the controls. In addition, the extent of their central VF was positively correlated with speech perception outcome (r = 0.669, P = 0.009). Persistent visual activation in right temporal cortex even after CI causes negative effect on outcome in post-lingual deaf adults. We interpret these results to suggest that insufficient intra-modal (visual) compensation by the occipital cortex may cause negative effects on outcome. Based on our results, it appears that a narrowed central VF could help identify CI users with poor outcomes with their device. PMID:26848755

Progress in Cochlear Physiology after Békésy

PubMed Central

Guinan, John J.; Salt, Alec; Cheatham, Mary Ann

2012-01-01

In the fifty years since Békésy was awarded the Nobel Prize, cochlear physiology has blossomed. Many topics that are now current are things Békésy could not have imagined. In this review we start by describing progress in understanding the origin of cochlear gross potentials, particularly the cochlear microphonic, an area in which Békésy had extensive experience. We then review progress in areas of cochlear physiology that were mostly unknown to Békésy, including: (1) stereocilia mechano-electrical transduction, force production, and response amplification, (2) outer hair cell (OHC) somatic motility and its molecular basis in prestin, (3) cochlear amplification and related micromechanics, including the evidence that prestin is the main motor for cochlear amplification, (4) the influence of the tectorial membrane, (5) cochlear micromechanics and the mechanical drives to inner hair cell stereocilia, (6) otoacoustic emissions, and (7) olivocochlear efferents and their influence on cochlear physiology. We then return to a subject that Békésy knew well: cochlear fluids and standing currents, as well as our present understanding of energy dependence on the lateral wall of the cochlea. Finally, we touch on cochlear pathologies including noise damage and aging, with an emphasis on where the field might go in the future. PMID:22633944

Effect of cochlear nerve electrocautery on the adult cochlear nucleus.

PubMed

Iseli, Claire E; Merwin, William H; Klatt-Cromwell, Cristine; Hutson, Kendall A; Ewend, Matthew G; Adunka, Oliver F; Fitzpatrick, Douglas C; Buchman, Craig A

2015-04-01

Electrocauterization and subsequent transection of the cochlear nerve induce greater injury to the cochlear nucleus than sharp transection alone. Some studies show that neurofibromatosis Type 2 (NF2) patients fit with auditory brainstem implants (ABIs) fail to achieve speech perception abilities similar to ABI recipients without NF2. Reasons for these differences remain speculative. One hypothesis posits poorer performance to surgically induced trauma to the cochlear nucleus from electrocautery. Sustained electrosurgical depolarization of the cochlear nerve may cause excitotoxic-induced postsynaptic nuclear injury. Equally plausible is that cautery in the vicinity of the cochlear nucleus induces necrosis. The cochlear nerve was transected in anesthetized adult gerbils sharply with or without bipolar electrocautery at varying intensities. Gerbils were perfused at 1, 3, 5, and 7 days postoperatively; their brainstem and cochleas were embedded in paraffin and sectioned at 10 μm. Alternate sections were stained with flourescent markers for neuronal injury or Nissl substance. In additional experiments, anterograde tracers were applied directly to a sectioned eighth nerve to verify that fluorescent-labeled profiles seen were terminating auditory nerve fibers. Cochlear nerve injury was observed from 72 hours postoperatively and was identical across cases regardless of surgical technique. Postsynaptic cochlear nucleus injury was not seen after distal transection of the nerve. By contrast, proximal transection was associated with trauma to the cochlear nucleus. Distal application of bipolar electrocautery seems safe for the cochlear nucleus. Application near the root entry zone must be used cautiously because this may compromise nuclear viability needed to support ABI stimulation.

Music Perception of Cochlear Implant Recipients with Implications for Music Instruction: A Review of Literature

PubMed Central

Hsiao, Feilin; Gfeller, Kate

2013-01-01

This review of literature presents a systematic analysis of the capabilities and limitations of cochlear implant recipients regarding music perception. Specifically, it a) analyzes individual components of music (e.g., rhythm, timbre, and pitch) as they interface with the technical characteristics of cochlear implants and the perceptual abilities of cochlear implant recipients; and b) describes accommodations for music instruction that support successful participation of children with cochlear implants. This article consolidates research studies from various disciplines (audiology, hearing science, speech-language pathology, cochlear implants, and music therapy) to provide practical recommendations for educators in fostering the musical growth of children with cochlear implants. PMID:23469365

Outcomes of cochlear implantation in deaf children of deaf parents: comparative study.

PubMed

Hassanzadeh, S

2012-10-01

This retrospective study compared the cochlear implantation outcomes of first- and second-generation deaf children. The study group consisted of seven deaf, cochlear-implanted children with deaf parents. An equal number of deaf children with normal-hearing parents were selected by matched sampling as a reference group. Participants were matched based on onset and severity of deafness, duration of deafness, age at cochlear implantation, duration of cochlear implantation, gender, and cochlear implant model. We used the Persian Auditory Perception Test for the Hearing Impaired, the Speech Intelligibility Rating scale, and the Sentence Imitation Test, in order to measure participants' speech perception, speech production and language development, respectively. Both groups of children showed auditory and speech development. However, the second-generation deaf children (i.e. deaf children of deaf parents) exceeded the cochlear implantation performance of the deaf children with hearing parents. This study confirms that second-generation deaf children exceed deaf children of hearing parents in terms of cochlear implantation performance. Encouraging deaf children to communicate in sign language from a very early age, before cochlear implantation, appears to improve their ability to learn spoken language after cochlear implantation.

Cochlear implant revision surgeries in children.

PubMed

Amaral, Maria Stella Arantes do; Reis, Ana Cláudia Mirândola B; Massuda, Eduardo T; Hyppolito, Miguel Angelo

2018-02-16

The surgery during which the cochlear implant internal device is implanted is not entirely free of risks and may produce problems that will require revision surgeries. To verify the indications for cochlear implantation revision surgery for the cochlear implant internal device, its effectiveness and its correlation with certain variables related to language and hearing. A retrospective study of patients under 18 years submitted to cochlear implant Surgery from 2004 to 2015 in a public hospital in Brazil. Data collected were: age at the time of implantation, gender, etiology of the hearing loss, audiological and oral language characteristics of each patient before and after Cochlear Implant surgery and any need for surgical revision and the reason for it. Two hundred and sixty-five surgeries were performed in 236 patients. Eight patients received a bilateral cochlear implant and 10 patients required revision surgery. Thirty-two surgeries were necessary for these 10 children (1 bilateral cochlear implant), of which 21 were revision surgeries. In 2 children, cochlear implant removal was necessary, without reimplantation, one with cochlear malformation due to incomplete partition type I and another due to trauma. With respect to the cause for revision surgery, of the 8 children who were successfully reimplanted, four had cochlear calcification following meningitis, one followed trauma, one exhibited a facial nerve malformation, one experienced a failure of the cochlear implant internal device and one revision surgery was necessary because the electrode was twisted. The incidence of the cochlear implant revision surgery was 4.23%. The period following the revision surgeries revealed an improvement in the subject's hearing and language performance, indicating that these surgeries are valid in most cases. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Parental expectations and outcomes of pediatric cochlear implantation.

PubMed

Piazza, Elizabeth; Kandathil, Cherian; Carron, Jeffrey D

2009-10-01

Cochlear implants have been used with increasing frequency over the past twenty years, including very young patients. To determine if parents are satisfied with their children's performance after cochlear implantation. Survey mailed to parents of children receiving cochlear implants. 31 questionnaires were returned out of 69 mailed (45 %). The vast majority of responding parents felt that their children benefited substantially from cochlear implant surgery. Cochlear implantation is effective in helping children develop auditory-oral communication skills. Access to auditory/oral communication programs in this state remains an obstacle in postoperative habilitation.

Drug delivery into the cochlear apex: Improved control to sequentially affect finely spaced regions along the entire length of the cochlear spiral.

PubMed

Lichtenhan, J T; Hartsock, J; Dornhoffer, J R; Donovan, K M; Salt, A N

2016-11-01

Administering pharmaceuticals to the scala tympani of the inner ear is a common approach to study cochlear physiology and mechanics. We present here a novel method for in vivo drug delivery in a controlled manner to sealed ears. Injections of ototoxic solutions were applied from a pipette sealed into a fenestra in the cochlear apex, progressively driving solutions along the length of scala tympani toward the cochlear aqueduct at the base. Drugs can be delivered rapidly or slowly. In this report we focus on slow delivery in which the injection rate is automatically adjusted to account for varying cross sectional area of the scala tympani, therefore driving a solution front at uniform rate. Objective measurements originating from finely spaced, low- to high-characteristic cochlear frequency places were sequentially affected. Comparison with existing methods(s): Controlled administration of pharmaceuticals into the cochlear apex overcomes a number of serious limitations of previously established methods such as cochlear perfusions with an injection pipette in the cochlear base: The drug concentration achieved is more precisely controlled, drug concentrations remain in scala tympani and are not rapidly washed out by cerebrospinal fluid flow, and the entire length of the cochlear spiral can be treated quickly or slowly with time. Controlled administration of solutions into the cochlear apex can be a powerful approach to sequentially effect objective measurements originating from finely spaced cochlear regions and allows, for the first time, the spatial origin of CAPs to be objectively defined. Copyright © 2016 Elsevier B.V. All rights reserved.

Drug delivery into the cochlear apex: Improved control to sequentially affect finely spaced regions along the entire length of the cochlear spiral

PubMed Central

Lichtenhan, JT; Hartsock, J; Dornhoffer, JR; Donovan, KM; Salt, AN

2016-01-01

Background Administering pharmaceuticals to the scala tympani of the inner ear is a common approach to study cochlear physiology and mechanics. We present here a novel method for in vivo drug delivery in a controlled manner to sealed ears. New method Injections of ototoxic solutions were applied from a pipette sealed into a fenestra in the cochlear apex, progressively driving solutions along the length of scala tympani toward the cochlear aqueduct at the base. Drugs can be delivered rapidly or slowly. In this report we focus on slow delivery in which the injection rate is automatically adjusted to account for varying cross sectional area of the scala tympani, therefore driving a solution front at uniform rate. Results Objective measurements originating from finely spaced, low- to high-characteristic cochlear frequency places were sequentially affected. Comparison with existing methods(s): Controlled administration of pharmaceuticals into the cochlear apex overcomes a number of serious limitations of previously established methods such as cochlear perfusions with an injection pipette in the cochlear base: The drug concentration achieved is more precisely controlled, drug concentrations remain in scala tympani and are not rapidly washed out by cerebrospinal fluid flow, and the entire length of the cochlear spiral can be treated quickly or slowly with time. Conclusions Controlled administration of solutions into the cochlear apex can be a powerful approach to sequentially effect objective measurements originating from finely spaced cochlear regions and allows, for the first time, the spatial origin of CAPs to be objectively defined. PMID:27506463

Cochlear implantation in patients with bilateral cochlear trauma.

PubMed

Serin, Gediz Murat; Derinsu, Ufuk; Sari, Murat; Gergin, Ozgül; Ciprut, Ayça; Akdaş, Ferda; Batman, Cağlar

2010-01-01

Temporal bone fracture, which involves the otic capsule, can lead to complete loss of auditory and vestibular functions, whereas the patients without fractures may experience profound sensorineural hearing loss due to cochlear concussion. Cochlear implant is indicated in profound sensorineural hearing loss due to cochlear trauma but who still have an intact auditory nerve. This is a retrospective review study. We report 5 cases of postlingually deafened patients caused by cochlear trauma, who underwent cochlear implantation. Preoperative and postoperative hearing performance will be presented. These patients are cochlear implanted after the cochlear trauma in our department between 2001 and 2006. All patients performed very well with their implants, obtained open-set speech understanding. They all became good telephone users after implantation. Their performance in speech understanding was comparable to standard postlingual adult patients implanted. Cochlear implantation is an effective aural rehabilitation in profound sensorineural hearing loss caused by temporal bone trauma. Preoperative temporal bone computed tomography, magnetic resonance imaging, and promontorium stimulation testing are necessary to make decision for the surgery and to determine the side to be implanted. Surgery could be challenging and complicated because of anatomical irregularity. Moreover, fibrosis and partial or total ossification within the cochlea must be expected. Copyright 2010. Published by Elsevier Inc.

The Contribution of Cognitive Factors to Individual Differences in Understanding Noise-Vocoded Speech in Young and Older Adults

PubMed Central

Rosemann, Stephanie; Gießing, Carsten; Özyurt, Jale; Carroll, Rebecca; Puschmann, Sebastian; Thiel, Christiane M.

2017-01-01

Noise-vocoded speech is commonly used to simulate the sensation after cochlear implantation as it consists of spectrally degraded speech. High individual variability exists in learning to understand both noise-vocoded speech and speech perceived through a cochlear implant (CI). This variability is partly ascribed to differing cognitive abilities like working memory, verbal skills or attention. Although clinically highly relevant, up to now, no consensus has been achieved about which cognitive factors exactly predict the intelligibility of speech in noise-vocoded situations in healthy subjects or in patients after cochlear implantation. We aimed to establish a test battery that can be used to predict speech understanding in patients prior to receiving a CI. Young and old healthy listeners completed a noise-vocoded speech test in addition to cognitive tests tapping on verbal memory, working memory, lexicon and retrieval skills as well as cognitive flexibility and attention. Partial-least-squares analysis revealed that six variables were important to significantly predict vocoded-speech performance. These were the ability to perceive visually degraded speech tested by the Text Reception Threshold, vocabulary size assessed with the Multiple Choice Word Test, working memory gauged with the Operation Span Test, verbal learning and recall of the Verbal Learning and Retention Test and task switching abilities tested by the Comprehensive Trail-Making Test. Thus, these cognitive abilities explain individual differences in noise-vocoded speech understanding and should be considered when aiming to predict hearing-aid outcome. PMID:28638329

Radiologic and functional evaluation of electrode dislocation from the scala tympani to the scala vestibuli in patients with cochlear implants.

PubMed

Fischer, N; Pinggera, L; Weichbold, V; Dejaco, D; Schmutzhard, J; Widmann, G

2015-02-01

Localization of the electrode after cochlear implantation seems to have an impact on auditory outcome, and conebeam CT has emerged as a reliable method for visualizing the electrode array position within the cochlea. The aim of this retrospective study was to evaluate the frequency and clinical impact of scalar dislocation of various electrodes and surgical approaches and to evaluate its influence on auditory outcome. This retrospective single-center study analyzed a consecutive series of 63 cochlear implantations with various straight electrodes. The placement of the electrode array was evaluated by using multiplanar reconstructed conebeam CT images. For the auditory outcome, we compared the aided hearing thresholds and the charge units of maximum comfortable loudness level at weeks 6, 12, and 24 after implantation. In 7.9% of the cases, the electrode array showed scalar dislocation. In all cases, the electrode array penetrated the basal membrane within 45° of the electrode insertion. All 3 cases of cochleostomy were dislocated in the first 45° segment. No hearing differences were noted, but the charge units of maximum comfortable loudness level seemed to increase with time in patients with dislocations. The intracochlear dislocation rate of various straight electrodes detected by conebeam CT images is relatively low. Scalar dislocation may not negatively influence the hearing threshold but may require an increase of the necessary stimulus charge and should be reported by the radiologist. © 2015 by American Journal of Neuroradiology.

Label-Free Ferrocene-Loaded Nanocarrier Engineering for In Vivo Cochlear Drug Delivery and Imaging.

PubMed

Youm, Ibrahima; Musazzi, Umberto M; Gratton, Michael Anne; Murowchick, James B; Youan, Bi-Botti C

2016-10-01

It is hypothesized that ferrocene (FC)-loaded nanocarriers (FC-NCs) are safe label-free contrast agents for cochlear biodistribution study by transmission electron microscopy (TEM). To test this hypothesis, after engineering, the poly(epsilon-caprolactone)/polyglycolide NCs are tested for stability with various types and ratios of sugar cryoprotectants during freeze-drying. Their physicochemical properties are characterized by UV-visible spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDS). The biodistribution of the FC-NCs in the cochlear tissue after intratympanic injection in guinea pigs is visualized by TEM. Auditory brainstem responses are measured before and after 4-day treatments. These FC-NCs have 153.4 ± 8.7 nm, 85.5 ± 11.2%, and -22.1 ± 1.1 mV as mean diameters, percent drug association efficiency, and zeta potential, respectively (n = 3). The incorporation of FC into the NCs is confirmed by Fourier transform infrared spectroscopy and SEM/EDS spectra. Lactose (3:1 ratio, v/v) is the most effective stabilizer after a 12-day study. The administered NCs are visible by TEM in the scala media cells of the cochlea. Based on auditory brainstem response data, FC-NCs do not adversely affect hearing. Considering the electrondense, radioactive, and magnetic properties of iron inside FC, FC-NCs are promising nanotemplate for future inner ear theranostics. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Cochlear implanted children present vocal parameters within normal standards.

PubMed

de Souza, Lourdes Bernadete Rocha; Bevilacqua, Maria Cecília; Brasolotto, Alcione Ghedini; Coelho, Ana Cristina

2012-08-01

to compare acoustic and perceptual parameters regarding the voice of cochlear implanted children, with normal hearing children. this is a cross-sectional, quantitative and qualitative study. Thirty six cochlear implanted children aged between 3 y and 3 m to 5 y and 9 m and 25 children with normal hearing, aged between 3 y and 11 m and 6 y and 6 m, participated in this study. The recordings and the acoustics analysis of the sustained vowel/a/and spontaneous speech were performed using the PRAAT program. The parameters analyzed for the sustained vowel were the mean of the fundamental frequency, jitter, shimmer and harmonic-to-noise ratio (HNR). For the spontaneous speech, the minimum and maximum frequencies and the number of semitones were extracted. The perceptual analysis of the speech material was analyzed using visual-analogical scales of 100 points, composing the aspects related to the overall severity of the vocal deviation, roughness, breathiness, strain, pitch, loudness and resonance deviation, and instability. This last parameter was only analyzed for the sustained vowel. The results demonstrated that the majority of the vocal parameters analyzed in the samples of the implanted children disclosed values similar to those obtained by the group of children with normal hearing. implanted children who participate in a (re) habilitation and follow-up program, can present vocal characteristics similar to those vocal characteristics of children with normal hearing. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

AutoNR: an automated system that measures ECAP thresholds with the Nucleus Freedom cochlear implant via machine intelligence.

PubMed

Botros, Andrew; van Dijk, Bas; Killian, Matthijs

2007-05-01

AutoNRT is an automated system that measures electrically evoked compound action potential (ECAP) thresholds from the auditory nerve with the Nucleus Freedom cochlear implant. ECAP thresholds along the electrode array are useful in objectively fitting cochlear implant systems for individual use. This paper provides the first detailed description of the AutoNRT algorithm and its expert systems, and reports the clinical success of AutoNRT to date. AutoNRT determines thresholds by visual detection, using two decision tree expert systems that automatically recognise ECAPs. The expert systems are guided by a dataset of 5393 neural response measurements. The algorithm approaches threshold from lower stimulus levels, ensuring recipient safety during postoperative measurements. Intraoperative measurements use the same algorithm but proceed faster by beginning at stimulus levels much closer to threshold. When searching for ECAPs, AutoNRT uses a highly specific expert system (specificity of 99% during training, 96% during testing; sensitivity of 91% during training, 89% during testing). Once ECAPs are established, AutoNRT uses an unbiased expert system to determine an accurate threshold. Throughout the execution of the algorithm, recording parameters (such as implant amplifier gain) are automatically optimised when needed. In a study that included 29 intraoperative and 29 postoperative subjects (a total of 418 electrodes), AutoNRT determined a threshold in 93% of cases where a human expert also determined a threshold. When compared to the median threshold of multiple human observers on 77 randomly selected electrodes, AutoNRT performed as accurately as the 'average' clinician. AutoNRT has demonstrated a high success rate and a level of performance that is comparable with human experts. It has been used in many clinics worldwide throughout the clinical trial and commercial launch of Nucleus Custom Sound Suite, significantly streamlining the clinical procedures associated with cochlear implant use.

Comparison of activated caspase detection methods in the gentamicin-treated chick cochlea

PubMed Central

Kaiser, Christina L.; Chapman, Brittany J.; Guidi, Jessica L.; Terry, Caitlin E.; Mangiardi, Dominic A.; Cotanche, Douglas A.

2008-01-01

Aminoglycoside antibiotics induce caspase-dependent apoptotic death in cochlear hair cells. Apoptosis, a regulated form of cell death, can be induced by many stressors, which activate signaling pathways that result in the controlled dismantling of the affected cell. The caspase family of proteases is activated in the apoptotic signaling pathway and is responsible for cellular destruction. The initiator caspase-9 and the effector caspase-3 are both activated in chick cochlear hair cells following aminoglycoside exposure. We have analyzed caspase activation in the avian cochlea during gentamicin-induced hair cell death to compare two different methods of caspase detection: caspase antibodies and CaspaTag kits. Caspase antibodies bind to the cleaved activated form of caspase-9 or caspase-3 in specific locations in fixed tissue. CaspaTag is a fluorescent inhibitor that binds to a reactive cysteine residue on the large subunit of the caspase heterodimer in unfixed tissue. To induce cochlear hair cell loss, 1-2 week-old chickens received a single injection of gentamicin (300 mg/kg). Chicks were sacrificed 24, 30, 42, 48, 72, or 96 h after injection. Cochleae were dissected and labeled for activated caspase-9 or caspase-3 using either caspase-directed antibodies or CaspaTag kits. Ears were co-labeled with either phalloidin or myosin VI to visualize hair cells and to determine the progression of cochlear damage. The timing of caspase activation was similar for both assays; however, caspase-9 and caspase-3 antibodies labeled only those cells currently undergoing apoptotic cell death. Conversely, CaspaTag-labeled all the cells that have undergone apoptotic cell death and ejection from the sensory epithelium, in addition to those that are currently in the cell death process. This makes CaspaTag ideal for showing an overall pattern or level of cell death over a period of time, while caspase antibodies provide a snapshot of cell death at a specific time point. PMID:18487027

Understanding Language, Hearing Status, and Visual-Spatial Skills

PubMed Central

Marschark, Marc; Spencer, Linda J.; Durkin, Andreana; Borgna, Georgianna; Convertino, Carol; Machmer, Elizabeth; Kronenberger, William G.; Trani, Alexandra

2015-01-01

It is frequently assumed that deaf individuals have superior visual-spatial abilities relative to hearing peers and thus, in educational settings, they are often considered visual learners. There is some empirical evidence to support the former assumption, although it is inconsistent, and apparently none to support the latter. Three experiments examined visual-spatial and related cognitive abilities among deaf individuals who varied in their preferred language modality and use of cochlear implants (CIs) and hearing individuals who varied in their sign language skills. Sign language and spoken language assessments accompanied tasks involving visual-spatial processing, working memory, nonverbal logical reasoning, and executive function. Results were consistent with other recent studies indicating no generalized visual-spatial advantage for deaf individuals and suggested that their performance in that domain may be linked to the strength of their preferred language skills regardless of modality. Hearing individuals performed more strongly than deaf individuals on several visual-spatial and self-reported executive functioning measures, regardless of sign language skills or use of CIs. Findings are inconsistent with assumptions that deaf individuals are visual learners or are superior to hearing individuals across a broad range of visual-spatial tasks. Further, performance of deaf and hearing individuals on the same visual-spatial tasks was associated with differing cognitive abilities, suggesting that different cognitive processes may be involved in visual-spatial processing in these groups. PMID:26141071

Phylogeny and evolutionary radiation of the marine mussels (Bivalvia: Mytilidae) based on mitochondrial and nuclear genes.

PubMed

Liu, Jun; Liu, Helu; Zhang, Haibin

2018-04-22

The marine mussels (Mytilidae) are distributed in the oceans worldwide and occupy various habitats with diverse life styles. However, their taxonomy and phylogeny remain unclear from genus to family level due to equivocal morphological and anatomical characters among some taxa. In this study, we inferred the deep phylogenetic relationships among 42 mytiloid species, 19 genera, and five subfamilies of the extant marine mussels by using two mitochondrial (COI and 16S rRNA) and three nuclear (18S and 28S rRNA, and histone H3) genes. Phylogeny was reconstructed with a combination of five genes using Bayesian inference and maximum likelihood method, and divergence time was estimated for the major nodes using a relaxed clock model with three fossil calibrations. Phylogenetic trees revealed two major clades (Clades 1 and 2). In Clade 1, the deep-sea mussels (subfamily Bathymodiolinae) were sister to subfamily Modiolinae (represented by Modiolus), and then was clustered with Leiosolenus (subfamily Lithophaginae). Clade 2 comprised Lithophaga (Lithophaginae) and subfamily Mytilinae. Additionally, a Modiolus species and Musculus senhousia (subfamily Crenellinae) were positioned within the subfamily Mytilinae. The phylogenetic results strongly indicated monophyly of Mytilidae and Bathymodiolinae, polyphyly of Modiolinae and Lithophaginae, and paraphyly of Mytilinae. Divergence time estimation showed an ancient and gradual divergence in most mussel groups, whereas the deep-sea mussels originated recently and diverged rapidly during the Paleogene. The present study provides new insight into the evolutionary history of the marine mussels, and supports taxonomic revision for this important bivalve group. Copyright © 2018 Elsevier Inc. All rights reserved.

Auditory, visual, and auditory-visual perceptions of emotions by young children with hearing loss versus children with normal hearing.

PubMed

Most, Tova; Michaelis, Hilit

2012-08-01

This study aimed to investigate the effect of hearing loss (HL) on emotion-perception ability among young children with and without HL. A total of 26 children 4.0-6.6 years of age with prelingual sensory-neural HL ranging from moderate to profound and 14 children with normal hearing (NH) participated. They were asked to identify happiness, anger, sadness, and fear expressed by an actress when uttering the same neutral nonsense sentence. Their auditory, visual, and auditory-visual perceptions of the emotional content were assessed. The accuracy of emotion perception among children with HL was lower than that of the NH children in all 3 conditions: auditory, visual, and auditory-visual. Perception through the combined auditory-visual mode significantly surpassed the auditory or visual modes alone in both groups, indicating that children with HL utilized the auditory information for emotion perception. No significant differences in perception emerged according to degree of HL. In addition, children with profound HL and cochlear implants did not perform differently from children with less severe HL who used hearing aids. The relatively high accuracy of emotion perception by children with HL may be explained by their intensive rehabilitation, which emphasizes suprasegmental and paralinguistic aspects of verbal communication.

Cochlear implant in Hong Kong Cantonese.

PubMed

Tang, S O; Luk, W S; Lau, C C; So, K W; Wong, C M; Yiu, M L; Kwok, C L

1990-11-01

Cochlear implant surgery was performed in four Cantonese-speaking postlingually deaf Chinese adults, using the House/3M single channel device. This article outlines the methodology, including preoperative assessment and postoperative rehabilitation; and explains the necessary modifications in speech and audiologic work-up in Cantonese-speaking patients. Salient features of Cantonese phonetics, especially its tonal characteristics, are described. The findings of the study are presented. The results of the cochlear implant would suggest a performance superior to that of the hearing aid. Furthermore, the cochlear implant is able to detect tonal cues. This quality of the cochlear implant may prove to be a valuable asset to a tonal language-speaking cochlear implantee.

Computer-assisted reading intervention with a phonics approach for children using cochlear implants or hearing aids.

PubMed

Nakeva von Mentzer, Cecilia; Lyxell, Björn; Sahlén, Birgitta; Dahlström, Orjan; Lindgren, Magnus; Ors, Marianne; Kallioinen, Petter; Uhlén, Inger

2014-10-01

The present study examined computer-assisted reading intervention with a phonics approach for deaf and hard of hearing (DHH) children in Sweden using cochlear implants or hearing aids, or a combination of both. The study included 48 children, 5, 6 and 7 years of age. Sixteen children with normal hearing (NH) served as a reference group. The first purpose of the study was to compare NH and DHH children's reading ability at pre and post-intervention. The second purpose was to investigate effects of the intervention. Cognitive and demographic factors were analyzed in relation to reading improvement. Results showed no statistically significant difference for reading ability at the group level, although NH children showed overall higher reading scores at both test points. Age comparisons revealed a statistically significant higher reading ability in the NH 7-year-olds compared to the DHH 7-year-olds. The intervention proved successful for word decoding accuracy, passage comprehension and as a reduction of nonword decoding errors in both NH and DHH children. Reading improvement was associated with complex working memory and phonological processing skills in NH children. Correspondent associations were observed with visual working memory and letter knowledge in the DHH children. Age was the only demographic factor that was significantly correlated with reading improvement. The results suggest that DHH children's beginning reading may be influenced by visual strategies that might explain the reading delay in the older children. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Internet video telephony allows speech reading by deaf individuals and improves speech perception by cochlear implant users.

PubMed

Mantokoudis, Georgios; Dähler, Claudia; Dubach, Patrick; Kompis, Martin; Caversaccio, Marco D; Senn, Pascal

2013-01-01

To analyze speech reading through Internet video calls by profoundly hearing-impaired individuals and cochlear implant (CI) users. Speech reading skills of 14 deaf adults and 21 CI users were assessed using the Hochmair Schulz Moser (HSM) sentence test. We presented video simulations using different video resolutions (1280 × 720, 640 × 480, 320 × 240, 160 × 120 px), frame rates (30, 20, 10, 7, 5 frames per second (fps)), speech velocities (three different speakers), webcameras (Logitech Pro9000, C600 and C500) and image/sound delays (0-500 ms). All video simulations were presented with and without sound and in two screen sizes. Additionally, scores for live Skype™ video connection and live face-to-face communication were assessed. Higher frame rate (>7 fps), higher camera resolution (>640 × 480 px) and shorter picture/sound delay (<100 ms) were associated with increased speech perception scores. Scores were strongly dependent on the speaker but were not influenced by physical properties of the camera optics or the full screen mode. There is a significant median gain of +8.5%pts (p = 0.009) in speech perception for all 21 CI-users if visual cues are additionally shown. CI users with poor open set speech perception scores (n = 11) showed the greatest benefit under combined audio-visual presentation (median speech perception +11.8%pts, p = 0.032). Webcameras have the potential to improve telecommunication of hearing-impaired individuals.

Cochlear implants: system design, integration, and evaluation.

PubMed

Zeng, Fan-Gang; Rebscher, Stephen; Harrison, William; Sun, Xiaoan; Feng, Haihong

2008-01-01

As the most successful neural prosthesis, cochlear implants have provided partial hearing to more than 120000 persons worldwide; half of which being pediatric users who are able to develop nearly normal language. Biomedical engineers have played a central role in the design, integration and evaluation of the cochlear implant system, but the overall success is a result of collaborative work with physiologists, psychologists, physicians, educators, and entrepreneurs. This review presents broad yet in-depth academic and industrial perspectives on the underlying research and ongoing development of cochlear implants. The introduction accounts for major events and advances in cochlear implants, including dynamic interplays among engineers, scientists, physicians, and policy makers. The review takes a system approach to address critical issues in cochlear implant research and development. First, the cochlear implant system design and specifications are laid out. Second, the design goals, principles, and methods of the subsystem components are identified from the external speech processor and radio frequency transmission link to the internal receiver, stimulator and electrode arrays. Third, system integration and functional evaluation are presented with respect to safety, reliability, and challenges facing the present and future cochlear implant designers and users. Finally, issues beyond cochlear implants are discussed to address treatment options for the entire spectrum of hearing impairment as well as to use the cochlear implant as a model to design and evaluate other similar neural prostheses such as vestibular and retinal implants.

Sound-direction identification with bilateral cochlear implants.

PubMed

Neuman, Arlene C; Haravon, Anita; Sislian, Nicole; Waltzman, Susan B

2007-02-01

The purpose of this study was to compare the accuracy of sound-direction identification in the horizontal plane by bilateral cochlear implant users when localization was measured with pink noise and with speech stimuli. Eight adults who were bilateral users of Nucleus 24 Contour devices participated in the study. All had received implants in both ears in a single surgery. Sound-direction identification was measured in a large classroom by using a nine-loudspeaker array. Localization was tested in three listening conditions (bilateral cochlear implants, left cochlear implant, and right cochlear implant), using two different stimuli (a speech stimulus and pink noise bursts) in a repeated-measures design. Sound-direction identification accuracy was significantly better when using two implants than when using a single implant. The mean root-mean-square error was 29 degrees for the bilateral condition, 54 degrees for the left cochlear implant, and 46.5 degrees for the right cochlear implant condition. Unilateral accuracy was similar for right cochlear implant and left cochlear implant performance. Sound-direction identification performance was similar for speech and pink noise stimuli. The data obtained in this study add to the growing body of evidence that sound-direction identification with bilateral cochlear implants is better than with a single implant. The similarity in localization performance obtained with the speech and pink noise supports the use of either stimulus for measuring sound-direction identification.

Cochlear Implants Special Issue Article: Vocal Emotion Recognition by Normal-Hearing Listeners and Cochlear Implant Users

PubMed Central

Luo, Xin; Fu, Qian-Jie; Galvin, John J.

2007-01-01

The present study investigated the ability of normal-hearing listeners and cochlear implant users to recognize vocal emotions. Sentences were produced by 1 male and 1 female talker according to 5 target emotions: angry, anxious, happy, sad, and neutral. Overall amplitude differences between the stimuli were either preserved or normalized. In experiment 1, vocal emotion recognition was measured in normal-hearing and cochlear implant listeners; cochlear implant subjects were tested using their clinically assigned processors. When overall amplitude cues were preserved, normal-hearing listeners achieved near-perfect performance, whereas listeners with cochlear implant recognized less than half of the target emotions. Removing the overall amplitude cues significantly worsened mean normal-hearing and cochlear implant performance. In experiment 2, vocal emotion recognition was measured in listeners with cochlear implant as a function of the number of channels (from 1 to 8) and envelope filter cutoff frequency (50 vs 400 Hz) in experimental speech processors. In experiment 3, vocal emotion recognition was measured in normal-hearing listeners as a function of the number of channels (from 1 to 16) and envelope filter cutoff frequency (50 vs 500 Hz) in acoustic cochlear implant simulations. Results from experiments 2 and 3 showed that both cochlear implant and normal-hearing performance significantly improved as the number of channels or the envelope filter cutoff frequency was increased. The results suggest that spectral, temporal, and overall amplitude cues each contribute to vocal emotion recognition. The poorer cochlear implant performance is most likely attributable to the lack of salient pitch cues and the limited functional spectral resolution. PMID:18003871

Cell migration, intercalation and growth regulate mammalian cochlear extension.

PubMed

Driver, Elizabeth Carroll; Northrop, Amy; Kelley, Matthew W

2017-10-15

Developmental remodeling of the sensory epithelium of the cochlea is required for the formation of an elongated, tonotopically organized auditory organ, but the cellular processes that mediate these events are largely unknown. We used both morphological assessments of cellular rearrangements and time-lapse imaging to visualize cochlear remodeling in mouse. Analysis of cell redistribution showed that the cochlea extends through a combination of radial intercalation and cell growth. Live imaging demonstrated that concomitant cellular intercalation results in a brief period of epithelial convergence, although subsequent changes in cell size lead to medial-lateral spreading. Supporting cells, which retain contact with the basement membrane, exhibit biased protrusive activity and directed movement along the axis of extension. By contrast, hair cells lose contact with the basement membrane, but contribute to continued outgrowth through increased cell size. Regulation of cellular protrusions, movement and intercalation within the cochlea all require myosin II. These results establish, for the first time, many of the cellular processes that drive the distribution of sensory cells along the tonotopic axis of the cochlea. © 2017. Published by The Company of Biologists Ltd.

[Emotional response to music by postlingually-deafened adult cochlear implant users].

PubMed

Wang, Shuo; Dong, Ruijuan; Zhou, Yun; Li, Jing; Qi, Beier; Liu, Bo

2012-10-01

To assess the emotional response to music by postlingually-deafened adult cochlear implant users. Munich music questionnaire (MUMU) was used to match the music experience and the motivation of use of music between 12 normal-hearing and 12 cochlear implant subjects. Emotion rating test in Musical Sounds in Cochlear Implants (MuSIC) test battery was used to assess the emotion perception ability for both normal-hearing and cochlear implant subjects. A total of 15 pieces of music phases were used. Responses were given by selecting the rating scales from 1 to 10. "1" represents "very sad" feeling, and "10" represents "very happy feeling. In comparison with normal-hearing subjects, 12 cochlear implant subjects made less active use of music for emotional purpose. The emotion ratings for cochlear implant subjects were similar to normal-hearing subjects, but with large variability. Post-lingually deafened cochlear implant subjects on average performed similarly in emotion rating tasks relative to normal-hearing subjects, but their active use of music for emotional purpose was obviously less than normal-hearing subjects.

The cochlear size of bats and rodents derived from MRI images and histology.

PubMed

Hsiao, Chun Jen; Jen, Philip Hung-Sun; Wu, Chung Hsin

2015-05-27

From the evolutionary perspective, the ear of each animal species is built for effective processing of the biologically relevant signals used for communication and acoustically guided orientation. Because the sound pulses used by echolocating bats for orientation and rodents for communication are quite different, the basic design of the mammalian auditory system commonly shared by echolocating bats must be specialized in some manner to effectively process their species-specific sounds. The present study examines the difference in the cochlea of these animal species using MRI images and histological techniques. We report here that, although all these animal species share a similar cochlear structure, they vary in their cochlear size and turns. Bats using constant frequency-frequency-modulated pulses (CF-FM bats) and frequency-modulated pulses (FM bats) for echolocation have a larger cochlear size and more cochlear turns than rodents (mice and rats). However, CF-FM bats have the largest cochlear size and most cochlear turns. This difference in cochlear size and turns of these animal species is discussed in relation to their biologically relevant sounds and acoustic behavior.

Guideline on cochlear implants.

PubMed

Manrique, Manuel; Ramos, Ángel; de Paula Vernetta, Carlos; Gil-Carcedo, Elisa; Lassaleta, Luis; Sanchez-Cuadrado, Isabel; Espinosa, Juan Manuel; Batuecas, Ángel; Cenjor, Carlos; Lavilla, María José; Núñez, Faustino; Cavalle, Laura; Huarte, Alicia

2018-03-26

In the last decade numerous hospitals have started to work with patients who are candidates for a cochlear implant (CI) and there have been numerous and relevant advances in the treatment of sensorineural hearing loss that extended the indications for cochlear implants. To provide a guideline on cochlear implants to specialists in otorhinolaryngology, other medical specialities, health authorities and society in general. The Scientific Committees of Otology, Otoneurology and Audiology from the Spanish Society of Otolaryngology and Head and Neck Surgery (SEORL-CCC), in a coordinated and agreed way, performed a review of the current state of CI based on the existing regulations and in the scientific publications referenced in the bibliography of the document drafted. The clinical guideline on cochlear implants provides information on: a) Definition and description of Cochlear Implant; b) Indications for cochlear implants; c) Organizational requirements for a cochlear implant programme. A clinical guideline on cochlear implants has been developed by a Committee of Experts of the SEORL-CCC, to help and guide all the health professionals involved in this field of CI in decision-making to treathearing impairment. Copyright © 2018 Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. Publicado por Elsevier España, S.L.U. All rights reserved.

Cochlear implants in children implanted in Jordan: A parental overview.

PubMed

Alkhamra, Rana A

2015-07-01

Exploring the perspective of parents on the cochlear implant process in Jordan. Sixty parents of deaf children were surveyed on the information gathering process prior to cochlear implant surgery, and their implant outcome expectations post-surgery. Whether child or parent characteristics may impact parents' post-surgical expectations was explored. Although parents used a variety of information sources when considering a cochlear implant, the ear, nose and throat doctor comprised their major source of information (60%). Parents received a range of information prior to cochlear implant but agreed (93.3%) on the need for a multidisciplinary team approach. Post-surgically, parents' expected major developments in the areas of spoken language (97%), and auditory skills (100%). Receiving education in mainstream schools (92%) was expected too. Parents perceived the cochlear implant decision as the best decision they can make for their child (98.3%). A significant correlation was found between parents contentment with the cochlear implant decision and expecting developments in the area of reading and writing (r=0.7). Child's age at implantation and age at hearing loss diagnosis significantly affected parents' post-implant outcome expectations (p<0.05). Despite the general satisfaction from the information quantity and quality prior to cochlear implant, parents agree on the need for a comprehensive multidisciplinary team approach during the different stages of the cochlear implant process. Parents' education about cochlear implants prior to the surgery can affect their post-surgical outcome expectations. The parental perspective presented in this study can help professionals develop better understanding of parents' needs and expectations and henceforth improve their services and support during the different stages of the cochlear implant process. Copyright © 2015. Published by Elsevier Ireland Ltd.

Bilateral cochlear implantation in a patient with bilateral temporal bone fractures.

PubMed

Chung, Jae Ho; Shin, Myung Chul; Min, Hyun Jung; Park, Chul Won; Lee, Seung Hwan

2011-01-01

With the emphasis on bilateral hearing nowadays, bilateral cochlear implantation has been tried out for bilateral aural rehabilitation. Bilateral sensorineural hearing loss caused by head trauma can get help from cochlear implantation. We present the case of a 44-year-old man with bilateral otic capsule violating temporal bone fractures due to head trauma. The patient demonstrated much improved audiometric and psychoacoustic performance after bilateral cochlear implantation. We believe bilateral cochlear implantation in such patient can be a very effective tool for rehabilitation. Copyright © 2011 Elsevier Inc. All rights reserved.

Close-field electroporation gene delivery using the cochlear implant electrode array enhances the bionic ear.

PubMed

Pinyon, Jeremy L; Tadros, Sherif F; Froud, Kristina E; Y Wong, Ann C; Tompson, Isabella T; Crawford, Edward N; Ko, Myungseo; Morris, Renée; Klugmann, Matthias; Housley, Gary D

2014-04-23

The cochlear implant is the most successful bionic prosthesis and has transformed the lives of people with profound hearing loss. However, the performance of the "bionic ear" is still largely constrained by the neural interface itself. Current spread inherent to broad monopolar stimulation of the spiral ganglion neuron somata obviates the intrinsic tonotopic mapping of the cochlear nerve. We show in the guinea pig that neurotrophin gene therapy integrated into the cochlear implant improves its performance by stimulating spiral ganglion neurite regeneration. We used the cochlear implant electrode array for novel "close-field" electroporation to transduce mesenchymal cells lining the cochlear perilymphatic canals with a naked complementary DNA gene construct driving expression of brain-derived neurotrophic factor (BDNF) and a green fluorescent protein (GFP) reporter. The focusing of electric fields by particular cochlear implant electrode configurations led to surprisingly efficient gene delivery to adjacent mesenchymal cells. The resulting BDNF expression stimulated regeneration of spiral ganglion neurites, which had atrophied 2 weeks after ototoxic treatment, in a bilateral sensorineural deafness model. In this model, delivery of a control GFP-only vector failed to restore neuron structure, with atrophied neurons indistinguishable from unimplanted cochleae. With BDNF therapy, the regenerated spiral ganglion neurites extended close to the cochlear implant electrodes, with localized ectopic branching. This neural remodeling enabled bipolar stimulation via the cochlear implant array, with low stimulus thresholds and expanded dynamic range of the cochlear nerve, determined via electrically evoked auditory brainstem responses. This development may broadly improve neural interfaces and extend molecular medicine applications.

Predicting social functioning in children with a cochlear implant and in normal-hearing children: the role of emotion regulation.

PubMed

Wiefferink, Carin H; Rieffe, Carolien; Ketelaar, Lizet; Frijns, Johan H M

2012-06-01

The purpose of the present study was to compare children with a cochlear implant and normal hearing children on aspects of emotion regulation (emotion expression and coping strategies) and social functioning (social competence and externalizing behaviors) and the relation between emotion regulation and social functioning. Participants were 69 children with cochlear implants (CI children) and 67 normal hearing children (NH children) aged 1.5-5 years. Parents answered questionnaires about their children's language skills, social functioning, and emotion regulation. Children also completed simple tasks to measure their emotion regulation abilities. Cochlear implant children had fewer adequate emotion regulation strategies and were less socially competent than normal hearing children. The parents of cochlear implant children did not report fewer externalizing behaviors than those of normal hearing children. While social competence in normal hearing children was strongly related to emotion regulation, cochlear implant children regulated their emotions in ways that were unrelated with social competence. On the other hand, emotion regulation explained externalizing behaviors better in cochlear implant children than in normal hearing children. While better language skills were related to higher social competence in both groups, they were related to fewer externalizing behaviors only in cochlear implant children. Our results indicate that cochlear implant children have less adequate emotion-regulation strategies and less social competence than normal hearing children. Since they received their implants relatively recently, they might eventually catch up with their hearing peers. Longitudinal studies should further explore the development of emotion regulation and social functioning in cochlear implant children. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

[The development of musicality in children after cochlear implantation].

PubMed

Zheng, Yan; Liu, Bo; Dong, Ruijuan; Xu, Tianqiu; Chen, Jing; Chen, Xuejing; Zhong, Yan; Meng, Chao; Wang, Hong; Chen, Xueqing

2014-08-01

The purpose of this study is to analyze the development of musicality in children after cochlear implantation, and provide a clinical database for the evaluation of their musicality. Twenty-six children with cochlear implants (CI group) participated in this research. They received cochlear implants at the age of 11 to 68 months with a mean of 35.6 months. Seventy-six infants as a control group aged from 1 to 24 months with a mean of 6.1 months participated in this study, whose hearing were considered normal by passing the case history collection, high-risk registers for hearing loss and hearing screening using DPOAE. The music and young children with CIs: Musicality Rating Scale was used to evaluate their musicality. The evaluation was performed before cochlear implantation and 1, 3, 6, 9, 12, 24 months after cochlear implantation for children with cochlear implants. The evaluation was also performed at 1, 3, 6, 9, 12, 24 months for children with normal hearing. The mean scores of musicality showed significant improvements with time of CI use for CI group (P<0.05). The mean scores of musicality also showed significant improvements with time for control group (P<0.05). There were no significant differences in mean scores between CI group and control group at 1, 3, 6, 9, 12 months of hearing age by rank sum test (P>0.05). Significant difference was noted between the two groups at 24 months (P<0.05). The musicality of children with cochlear implants improved significantly with time after cochlear implantation. The most rapid growth was found in the first year after cochlear implantation.

Understanding Language, Hearing Status, and Visual-Spatial Skills.

PubMed

Marschark, Marc; Spencer, Linda J; Durkin, Andreana; Borgna, Georgianna; Convertino, Carol; Machmer, Elizabeth; Kronenberger, William G; Trani, Alexandra

2015-10-01

It is frequently assumed that deaf individuals have superior visual-spatial abilities relative to hearing peers and thus, in educational settings, they are often considered visual learners. There is some empirical evidence to support the former assumption, although it is inconsistent, and apparently none to support the latter. Three experiments examined visual-spatial and related cognitive abilities among deaf individuals who varied in their preferred language modality and use of cochlear implants (CIs) and hearing individuals who varied in their sign language skills. Sign language and spoken language assessments accompanied tasks involving visual-spatial processing, working memory, nonverbal logical reasoning, and executive function. Results were consistent with other recent studies indicating no generalized visual-spatial advantage for deaf individuals and suggested that their performance in that domain may be linked to the strength of their preferred language skills regardless of modality. Hearing individuals performed more strongly than deaf individuals on several visual-spatial and self-reported executive functioning measures, regardless of sign language skills or use of CIs. Findings are inconsistent with assumptions that deaf individuals are visual learners or are superior to hearing individuals across a broad range of visual-spatial tasks. Further, performance of deaf and hearing individuals on the same visual-spatial tasks was associated with differing cognitive abilities, suggesting that different cognitive processes may be involved in visual-spatial processing in these groups. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Automatic detection of the inner ears in head CT images using deep convolutional neural networks

NASA Astrophysics Data System (ADS)

Zhang, Dongqing; Noble, Jack H.; Dawant, Benoit M.

2018-03-01

Cochlear implants (CIs) use electrode arrays that are surgically inserted into the cochlea to stimulate nerve endings to replace the natural electro-mechanical transduction mechanism and restore hearing for patients with profound hearing loss. Post-operatively, the CI needs to be programmed. Traditionally, this is done by an audiologist who is blind to the positions of the electrodes relative to the cochlea and relies on the patient's subjective response to stimuli. This is a trial-and-error process that can be frustratingly long (dozens of programming sessions are not unusual). To assist audiologists, we have proposed what we call IGCIP for image-guided cochlear implant programming. In IGCIP, we use image processing algorithms to segment the intra-cochlear anatomy in pre-operative CT images and to localize the electrode arrays in post-operative CTs. We have shown that programming strategies informed by image-derived information significantly improve hearing outcomes for both adults and pediatric populations. We are now aiming at deploying these techniques clinically, which requires full automation. One challenge we face is the lack of standard image acquisition protocols. The content of the image volumes we need to process thus varies greatly and visual inspection and labelling is currently required to initialize processing pipelines. In this work we propose a deep learning-based approach to automatically detect if a head CT volume contains two ears, one ear, or no ear. Our approach has been tested on a data set that contains over 2,000 CT volumes from 153 patients and we achieve an overall 95.97% classification accuracy.

Cochlear Implants:System Design, Integration and Evaluation

PubMed Central

Rebscher, Stephen; Harrison, William V.; Sun, Xiaoan; Feng, Haihong

2009-01-01

As the most successful neural prosthesis, cochlear implants have provided partial hearing to more than 120,000 persons worldwide; half of which being pediatric users who are able to develop nearly normal language. Biomedical engineers have played a central role in the design, integration and evaluation of the cochlear implant system, but the overall success is a result of collaborative work with physiologists, psychologists, physicians, educators, and entrepreneurs. This review presents broad yet in-depth academic and industrial perspectives on the underlying research and ongoing development of cochlear implants. The introduction accounts for major events and advances in cochlear implants, including dynamic interplays among engineers, scientists, physicians, and policy makers. The review takes a system approach to address critical issues from design and specifications to integration and evaluation. First, the cochlear implant system design and specifications are laid out. Second, the design goals, principles, and methods of the subsystem components are identified from the external speech processor and radio frequency transmission link to the internal receiver, stimulator and electrode arrays. Third, system integration and functional evaluation are presented with respect to safety, reliability, and challenges facing the present and future cochlear implant designers and users. Finally, issues beyond cochlear implants are discussed to address treatment options for the entire spectrum of hearing impairment as well as to use the cochlear implant as a model to design and evaluate other similar neural prostheses such as vestibular and retinal implants. PMID:19946565

Remote programming of cochlear implants: a telecommunications model.

PubMed

McElveen, John T; Blackburn, Erin L; Green, J Douglas; McLear, Patrick W; Thimsen, Donald J; Wilson, Blake S

2010-09-01

Evaluate the effectiveness of remote programming for cochlear implants. Retrospective review of the cochlear implant performance for patients who had undergone mapping and programming of their cochlear implant via remote connection through the Internet. Postoperative Hearing in Noise Test and Consonant/Nucleus/Consonant word scores for 7 patients who had undergone remote mapping and programming of their cochlear implant were compared with the mean scores of 7 patients who had been programmed by the same audiologist over a 12-month period. Times required for remote and direct programming were also compared. The quality of the Internet connection was assessed using standardized measures. Remote programming was performed via a virtual private network with a separate software program used for video and audio linkage. All 7 patients were programmed successfully via remote connectivity. No untoward patient experiences were encountered. No statistically significant differences could be found in comparing postoperative Hearing in Noise Test and Consonant/Nucleus/Consonant word scores for patients who had undergone remote programming versus a similar group of patients who had their cochlear implant programmed directly. Remote programming did not require a significantly longer programming time for the audiologist with these 7 patients. Remote programming of a cochlear implant can be performed safely without any deterioration in the quality of the programming. This ability to remotely program cochlear implant patients gives the potential to extend cochlear implantation to underserved areas in the United States and elsewhere.

Protective role of hydrogen sulfide against noise-induced cochlear damage: a chronic intracochlear infusion model.

PubMed

Li, Xu; Mao, Xiao-Bo; Hei, Ren-Yi; Zhang, Zhi-Bin; Wen, Li-Ting; Zhang, Peng-Zhi; Qiu, Jian-Hua; Qiao, Li

2011-01-01

A reduction in cochlear blood flow plays an essential role in noise-induced hearing loss (NIHL). The timely regulation of cochlear perfusion determines the progression and prognosis of NIHL. Hydrogen sulfide (H(2)S) has attracted increasing interest as a vasodilator in cardiovascular systems. This study identified the role of H(2)S in cochlear blood flow regulation and noise protection. The gene and protein expression of the H(2)S synthetase cystathionine-γ-lyase (CSE) in the rat cochlea was examined using immunofluorescence and real-time PCR. Cochlear CSE mRNA levels varied according to the duration of noise exposure. A chronic intracochlear infusion model was built and artificial perilymph (AP), NaHS or DL-propargylglycine (PPG) were locally administered. Local sodium hydrosulfide (NaHS) significantly increased cochlear perfusion post-noise exposure. Cochlear morphological damage and hearing loss were alleviated in the NaHS group as measured by conventional auditory brainstem response (ABR), cochlear scanning electron microscope (SEM) and outer hair cell (OHC) count. The highest percentage of OHC loss occurred in the PPG group. Our results suggest that H(2)S plays an important role in the regulation of cochlear blood flow and the protection against noise. Further studies may identify a new preventive and therapeutic perspective on NIHL and other blood supply-related inner ear diseases.

Cochlear Patency After Transmastoid Labyrinthectomy for Ménière's Syndrome.

PubMed

Sargent, Eric W; Liao, Eric; Gonda, Roger L

2016-08-01

Labyrinthectomy is considered the "gold standard" in the treatment of intractable vertigo attacks because of Ménière's Disease (MD) but sacrifices all residual hearing. Interest in auditory rehabilitation has lead to cochlear implantation in some patients. Concern remains that the cochlear lumen may fill with tissue or bone after surgery. This study sought to determine the incidence of obliteration of the cochlea after transmastoid labyrinthectomy. Retrospective observational study. Tertiary referral center. Eighteen patients with intractable vertigo from MD who underwent surgery. Transmastoid labyrinthectomy between 2008 and 2013. Cochleas were imaged with unenhanced, heavily T2-weighted magnetic resonance imaging (MRI). Presence of symmetrical cochlear fluid signals on MRI. There was no loss of fluid signal in the cochleas of operated ear compared with the contralateral, unoperated ear in any subject an average of 3 years (standard deviation [SD]: 1.2) after surgery. Five of 18 patients had the vestibule blocked with bone wax at the time of surgery. Blocking the vestibule with bone wax did not change the cochlear fluid signal. The risk of cochlear obstruction after labyrinthectomy for MD is very low. The significance of this finding is that patients with MD who undergo labyrinthectomy will likely remain candidates for cochlear implantation in the labyrinthectomized ear long after surgery if this becomes needed. Immediate cochlear implantation or placement of a cochlear lumen keeper during labyrinthectomy for MD is probably not necessary.

Music mixing preferences of cochlear implant recipients: a pilot study.

PubMed

Buyens, Wim; van Dijk, Bas; Moonen, Marc; Wouters, Jan

2014-05-01

Music perception and appraisal are generally poor in cochlear implant recipients. Simple musical structures, lyrics that are easy to follow, and clear rhythm/beat have been reported among the top factors to enhance music enjoyment. The present study investigated the preference for modified relative instrument levels in music with normal-hearing and cochlear implant subjects. In experiment 1, test subjects were given a mixing console and multi-track recordings to determine their most enjoyable audio mix. In experiment 2, a preference rating experiment based on the preferred relative level settings in experiment 1 was performed. Experiment 1 was performed with four postlingually deafened cochlear implant subjects, experiment 2 with ten normal-hearing and ten cochlear implant subjects. A significant difference in preference rating was found between normal-hearing and cochlear implant subjects. The latter preferred an audio mix with larger vocals-to-instruments ratio. In addition, given an audio mix with clear vocals and attenuated instruments, cochlear implant subjects preferred the bass/drum track to be louder than the other instrument tracks. The original audio mix in real-world music might not be suitable for cochlear implant recipients. Modifying the relative instrument level settings potentially improves music enjoyment.

Betahistine metabolites, aminoethylpyridine, and hydroxyethylpyridine increase cochlear blood flow in guinea pigs in vivo.

PubMed

Bertlich, Mattis; Ihler, Fritz; Sharaf, Kariem; Weiss, Bernhard G; Strupp, Michael; Canis, Martin

2014-10-01

Betahistine is a histamine-like drug that is used in the treatment of Ménière's disease. It is commonly believed that betahistine increases cochlear blood flow and thus decreases the endolymphatic hydrops that is the cause of Ménière's. Despite common clinical use, there is little understanding of the kinetics or effects of its metabolites. This study investigated the effect of the betahistine metabolites aminoethylpyridine, hydroxyethylpyridine, and pyridylacetic acid on cochlear microcirculation. Guinea pigs were randomly assigned to one of the groups: placebo, betahistine, or equimolar amounts of aminoethylpyridine, hydroxyethylpyridine, or pyridylacetic acid. Cochlear blood flow and mean arterial pressure were recorded for three minutes before and 15 minutes after treatment. Thirty Dunkin-Hartley guinea pigs assigned to one of five groups with six guinea pigs per group. Betahistine, aminoethylpyridine, and hydroxyethylpyridine caused a significant increase in cochlear blood flow in comparison to placebo. The effect seen under aminoethylpyridin was greatest. The group treated with pyridylacetic acid showed no significant effect on cochlear blood flow. Aminoethylpyridine and hydroxyethylpyridine are, like betahistine, able to increase cochlear blood flow significantly. The effect of aminoethylpyridine was greatest. Pyridylacetic acid had no effect on cochlear microcirculation.

Histaminergic H3-Heteroreceptors as a Potential Mediator of Betahistine-Induced Increase in Cochlear Blood Flow.

PubMed

Bertlich, Mattis; Ihler, Friedrich; Freytag, Saskia; Weiss, Bernhard G; Strupp, Michael; Canis, Martin

2015-01-01

Betahistine is a histamine-like drug that is considered beneficial in Ménière's disease by increasing cochlear blood flow. Acting as an agonist at the histamine H1-receptor and as an inverse agonist at the H3-receptor, these receptors as well as the adrenergic α2-receptor were investigated for betahistine effects on cochlear blood flow. A total of 54 Dunkin-Hartley guinea pigs were randomly assigned to one of nine groups treated with a selection of H1-, H3- or α2-selective agonists and antagonists together with betahistine. Cochlear blood flow and mean arterial pressure were recorded for 3 min before and 15 min after infusion. Blockage of the H3- or α2-receptors caused a suppression of betahistine-mediated typical changes in cochlear blood flow or blood pressure. Activation of H3-receptors caused a drop in cochlear blood flow and blood pressure. H1-receptors showed no involvement in betahistine-mediated changes of cochlear blood flow. Betahistine most likely affects cochlear blood flow through histaminergic H3-heteroreceptors. © 2015 S. Karger AG, Basel.

Fingolimod (FTY-720) is Capable of Reversing Tumor Necrosis Factor Induced Decreases in Cochlear Blood Flow.

PubMed

Bertlich, Mattis; Ihler, Friedrich; Weiss, Bernhard G; Freytag, Saskia; Jakob, Mark; Strupp, Michael; Pellkofer, Hannah; Canis, Martin

2017-09-01

The potential of Fingolimod (FTY-720), a sphingosine-1-phosphate analogue, to revoke the changes in cochlear blood flow induced by tumor necrosis factor (TNF) was investigated. Impairment of cochlear blood flow has often been considered as the common final pathway of various inner ear pathologies. TNF, an ubiquitous cytokine, plays a major role in these pathologies, reducing cochlear blood flow via sphingosine-1-phosphate-signaling. Fifteen Dunkin-Hartley guinea pigs were randomly assigned to one of three groups (placebo/placebo, TNF/placebo, TNF/FTY-720). Cochlear microcirculation was quantified over 60 minutes by in vivo fluorescence microscopy before and after topical application of placebo or TNF (5 ng/ml) and after subsequent application of placebo or FTY-720 (200 μg/ml). Treatment with TNF led to a significant decrease of cochlear blood flow.Following this, application of placebo caused no significant changes while application of FTY-720 caused a significant rise in cochlear blood flow. FTY-720 is capable of reversing changes in cochlear blood flow induced by application of TNF. This makes FTY-720 a valid candidate for potential treatment of numerous inner ear pathologies.

[Cochlear implantation in patients with Waardenburg syndrome type II].

PubMed

Wan, Liangcai; Guo, Menghe; Chen, Shuaijun; Liu, Shuangriu; Chen, Hao; Gong, Jian

2010-05-01

To describe the multi-channel cochlear implantation in patients with Waardenburg syndrome including surgeries, pre and postoperative hearing assessments as well as outcomes of speech recognition. Multi-channel cochlear implantation surgeries have been performed in 12 cases with Waardenburg syndrome type II in our department from 2000 to 2008. All the patients received multi-channel cochlear implantation through transmastoid facial recess approach. The postoperative outcomes of 12 cases were compared with 12 cases with no inner ear malformation as a control group. The electrodes were totally inserted into the cochlear successfully, there was no facial paralysis and cerebrospinal fluid leakage occurred after operation. The hearing threshold in this series were similar to that of the normal cochlear implantation. After more than half a year of speech rehabilitation, the abilities of speech discrimination and spoken language of all the patients were improved compared with that of preoperation. Multi-channel cochlear implantation could be performed in the cases with Waardenburg syndrome, preoperative hearing and images assessments should be done.

[Cochlear implantation through the middle fossa approach].

PubMed

Szyfter, W; Colletti, V; Pruszewicz, A; Kopeć, T; Szymiec, E; Kawczyński, M; Karlik, M

2001-01-01

The inner part of cochlear implant is inserted into inner ear during surgery through mastoid and middle ear. It is a classical method, used in the majority cochlear centers in the world. This is not a suitable method in case of chronic otitis media and middle ear malformation. In these cases Colletti proposed the middle fossa approach and cochlear implant insertion omitting middle ear structures. In patient with bilateral chronic otitis media underwent a few ears operations without obtaining dry postoperative cavity. Cochlear implantation through the middle fossa approach was performed in this patient. The bone fenster was cut, temporal lobe was bent and petrosus pyramid upper surface was exposed. When the superficial petrosal greater nerve, facial nerve and arcuate eminence were localised, the cochlear was open in the basal turn and electrode were inserted. The patient achieves good results in the postoperative speech rehabilitation. It confirmed Colletti tesis that deeper electrode insertion in the cochlear implantation through the middle fossa approach enable use of low and middle frequencies, which are very important in speech understanding.

United Kingdom national paediatric bilateral cochlear implant audit: preliminary results.

PubMed

Cullington, Helen; Bele, Devyanee; Brinton, Julie; Lutman, Mark

2013-11-01

Prior to 2009, United Kingdom (UK) public funding was mainly only available for children to receive unilateral cochlear implants. In 2009, the National Institute for Health and Care Excellence published guidance for cochlear implantation following their review. According to these guidelines, all suitable children are eligible to have simultaneous bilateral cochlear implants or a sequential bilateral cochlear implant if they had received the first before the guidelines were published. Fifteen UK cochlear implant centres formed a consortium to carry out a multi-centre audit. The audit involves collecting data from simultaneously and sequentially implanted children at four intervals: before bilateral cochlear implants or before the sequential implant, 1, 2, and 3 years after bilateral implants. The measures include localization, speech recognition in quiet and background noise, speech production, listening, vocabulary, parental perception, quality of life, and surgical data including complications. The audit has now passed the 2-year point, and data have been received on 850 children. This article provides a first view of some data received up until March 2012.

Ischemia-reperfusion injury of the cochlea: pharmacological strategies for cochlear protection and implications of glutamate and reactive oxygen species.

PubMed

Tabuchi, Keiji; Nishimura, Bungo; Tanaka, Shuho; Hayashi, Kentaro; Hirose, Yuki; Hara, Akira

2010-06-01

A large amount of energy produced by active aerobic metabolism is necessary for the cochlea to maintain its function. This makes the cochlea vulnerable to blockade of cochlear blood flow and interruption of the oxygen supply. Although certain forms of human idiopathic sudden sensorineural hearing loss reportedly arise from ischemic injury, the pathological mechanism of cochlear ischemia-reperfusion injury has not been fully elucidated. Recent animal studies have shed light on the mechanisms of cochlear ischemia-reperfusion injury. It will help in the understanding of the pathology of cochlear ischemia-reperfusion injury to classify this injury into ischemic injury and reperfusion injury. Excitotoxicity, mainly observed during the ischemic period, aggravates the injury of primary auditory neurons. On the other hand, oxidative damage induced by hydroxyl radicals and nitric oxide enhances cochlear reperfusion injury. This article briefly summarizes the generation mechanisms of cochlear ischemia-reperfusion injury and potential therapeutic targets that could be developed for the effective management of this injury type.

Musical ear syndrome in adult cochlear implant patients.

PubMed

Low, W-K; Tham, C A; D'Souza, V-D; Teng, S-W

2013-09-01

Except for a single case report, musical ear syndrome in cochlear implantees has not been studied. We aimed to study the prevalence and nature of musical ear syndrome among adult cochlear implant patients, as well as the effect on their emotional well-being. STUDY DESIGN, PATIENTS AND INTERVENTION: A cross-sectional survey of patients aged 18 years and above who had received cochlear implants for profound hearing loss between 1997 and 2010. Of the 82 patients studied, 18 (22 per cent) were found to have experienced musical ear syndrome. Seven and 11 patients had musical ear syndrome prior to and after cochlear implantation, respectively. The character of musical ear syndrome symptoms was described as instrumental music (n = 2), singing (6) or both (10). Fourteen patients reported an adverse emotional effect, with three expressing ‘intolerance’. In this study, 22 per cent of cochlear implantees experienced musical ear syndrome. These symptoms affected patients’ emotional state, but most coped well. Musical ear syndrome can occur prior to and after cochlear implantation.

Importance of cochlear health for implant function.

PubMed

Pfingst, Bryan E; Zhou, Ning; Colesa, Deborah J; Watts, Melissa M; Strahl, Stefan B; Garadat, Soha N; Schvartz-Leyzac, Kara C; Budenz, Cameron L; Raphael, Yehoash; Zwolan, Teresa A

2015-04-01

Amazing progress has been made in providing useful hearing to hearing-impaired individuals using cochlear implants, but challenges remain. One such challenge is understanding the effects of partial degeneration of the auditory nerve, the target of cochlear implant stimulation. Here we review studies from our human and animal laboratories aimed at characterizing the health of the implanted cochlea and the auditory nerve. We use the data on cochlear and neural health to guide rehabilitation strategies. The data also motivate the development of tissue-engineering procedures to preserve or build a healthy cochlea and improve performance obtained by cochlear implant recipients or eventually replace the need for a cochlear implant. This article is part of a Special Issue entitled . Copyright © 2014 Elsevier B.V. All rights reserved.

The influence of cochlear shape on low-frequency hearing.

PubMed

Manoussaki, Daphne; Chadwick, Richard S; Ketten, Darlene R; Arruda, Julie; Dimitriadis, Emilios K; O'Malley, Jen T

2008-04-22

The conventional theory about the snail shell shape of the mammalian cochlea is that it evolved essentially and perhaps solely to conserve space inside the skull. Recently, a theory proposed that the spiral's graded curvature enhances the cochlea's mechanical response to low frequencies. This article provides a multispecies analysis of cochlear shape to test this theory and demonstrates that the ratio of the radii of curvature from the outermost and innermost turns of the cochlear spiral is a significant cochlear feature that correlates strongly with low-frequency hearing limits. The ratio, which is a measure of curvature gradient, is a reflection of the ability of cochlear curvature to focus acoustic energy at the outer wall of the cochlear canal as the wave propagates toward the apex of the cochlea.

Physiopathology of the cochlear microcirculation.

PubMed

Shi, Xiaorui

2011-12-01

Normal blood supply to the cochlea is critically important for establishing the endocochlear potential and sustaining production of endolymph. Abnormal cochlear microcirculation has long been considered an etiologic factor in noise-induced hearing loss, age-related hearing loss (presbycusis), sudden hearing loss or vestibular function, and Meniere's disease. Knowledge of the mechanisms underlying the pathophysiology of cochlear microcirculation is of fundamental clinical importance. A better understanding of cochlear blood flow (CoBF) will enable more effective management of hearing disorders resulting from aberrant blood flow. This review focuses on recent discoveries and findings related to the physiopathology of the cochlear microvasculature. Published by Elsevier B.V.

Physiopathology of the Cochlear Microcirculation

PubMed Central

Shi, Xiaorui

2011-01-01

Normal blood supply to the cochlea is critically important for establishing the endocochlear potential and sustaining production of endolymph. Abnormal cochlear microcirculation has long been considered an etiologic factor in noise-induced hearing loss, age-related hearing loss (presbycusis), sudden hearing loss or vestibular function, and Meniere's disease. Knowledge of the mechanisms underlying the pathophysiology of cochlear microcirculation is of fundamental clinical importance. A better understanding of cochlear blood flow (CoBF) will enable more effective management of hearing disorders resulting from aberrant blood flow. This review focuses on recent discoveries and findings related to the physiopathology of the cochlear microvasculature. PMID:21875658

Shell microstructures of mussels (Bivalvia: Mytilidae: Bathymodiolinae) from deep-sea chemosynthetic sites: Do they have a phylogenetic significance?

NASA Astrophysics Data System (ADS)

Génio, Luciana; Kiel, Steffen; Cunha, Marina R.; Grahame, John; Little, Crispin T. S.

2012-06-01

The increasing number of bathymodiolin mussel species being described from deep-sea chemosynthetic environments worldwide has raised many questions about their evolutionary history, and their systematics is still being debated. Mussels are also abundant in fossil chemosynthetic assemblages, but their identification is problematic due to conservative shell morphology within the group and preservation issues. Potential resolution of bathymodiolin taxonomy requires new character sets, including morphological features that are likely to be preserved in fossil specimens. To investigate the phylogenetic significance of shell microstructural features, we studied the shell microstructure and mineralogy of 10 mussel species from hydrothermal vents and hydrocarbon seeps, and 15 taxa from sunken wood and bone habitats, and compared these observations with current molecular phylogenies of the sub-family Bathymodiolinae. In addition, we analyzed the shell microstructure in Adipicola chickubetsuensis from fossil whale carcasses, and in Bathymodiolus cf. willapaensis and “Modiola exbrocchii” from fossil cold seeps, and discussed the usefulness of these characters for identification of fossil chemosymbiotic mussels. Microstructural shell features are quite uniform among vent, seep, wood and bone mussel taxa, and therefore established bathymodiolin lineages cannot be discriminated, nor can the relations between fossil and modern species be determined with these characters. Nevertheless, the uniformity of shell microstructures observed among chemosymbiotic mussels and the similarity with its closest relative, Modiolus modiolus, does not challenge the monophyly of the group. Slight differences are found between the large vent and seep mussels and the small mytilids commonly found in habitats enriched in organic matter. Together with previous data, these results indicate that a repeated pattern of paedomorphism characterizes the evolutionary history of deep-sea mussels, and the occurrence of neotenous features should be considered in the taxonomic revision of this group.

Working memory in Farsi-speaking children with normal development and cochlear implant.

PubMed

Soleymani, Zahra; Amidfar, Meysam; Dadgar, Hooshang; Jalaie, Shohre

2014-04-01

Working memory has an important role in language acquisition and development of cognition skills. The ability of encoding, storage and retrieval of phonological codes, as activities of working memory, acquired by audition sense. Children with cochlear implant experience a period that they are not able to perceive sounds. In order to assess the effect of hearing on working memory, we investigated working memory as a cognition skill in children with normal development and cochlear implant. Fifty students with normal hearing and 50 students with cochlear implant aged 5-7 years participated in this study. Children educated in the preschool, the first and second grades. Children with normal development were matched based on age, gender, and grade of education with cochlear implant. Two components of working memory including phonological loop and central executive were compared between two groups. Phonological loop assessed by nonword repetition task and forward digit span. To assess central executive component backward digit span was used. The developmental trend was studied in children with normal development and cochlear implant as well. The effect of age at implantation in children with cochlear implants on components of working memory was investigated. There are significant differences between children with normal development and cochlear implant in all tasks that assess working memory (p < 0.001). The children's age at implantation was negatively correlated with all tasks (p < 0.001). In contrast, duration of usage of cochlear implant set was positively correlated with all tasks (p < 0.001). The comparison of working memory between different grades showed significant differences both in children with normal development and in children with cochlear implant (p < 0.05). These results implied that children with cochlear implant may experience difficulties in working memory. Therefore, these children have problems in encoding, practicing, and repeating phonological units. The results also suggested working memory develops when the child grows up. In cochlear implant children, with decreasing age at implantation and increasing their experience in perceiving sound, working memory skills improved. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Lack of financial barriers to pediatric cochlear implantation: impact of socioeconomic status on access and outcomes.

PubMed

Chang, David T; Ko, Alvin B; Murray, Gail S; Arnold, James E; Megerian, Cliff A

2010-07-01

(1) To analyze if socioeconomic status influences access to cochlear implantation in an environment with adequate Medicaid reimbursement. (2) To determine the impact of socioeconomic status on outcomes after unilateral cochlear implantation. Retrospective cohort study. University Hospitals Case Medical Center and Rainbow Babies and Children's Hospital (tertiary referral center), Cleveland, Ohio. Pediatric patients (age range, newborn to 18 years) who received unilateral cochlear implantation during the period 1996 to 2008. Access to cochlear implantation after referral to a cochlear implant center, postoperative complications, compliance with follow-up appointments, and access to sequential bilateral cochlear implantation. A total of 133 pediatric patients were included in this study; 64 were Medicaid-insured patients and 69 were privately insured patients. There was no statistical difference in the odds of initial cochlear implantation, age at referral, or age at implantation between the 2 groups. The odds of prelingual Medicaid-insured patients receiving sequential bilateral cochlear implantation was less than half that of the privately insured group (odds ratio [OR], 0.43; P = .03). The odds of complications in Medicaid-insured children were almost 5-fold greater than the odds for privately insured children (OR, 4.6; P = .03). There were 10 complications in 51 Medicaid-insured patients (19.6%) as opposed to 3 in 61 privately insured patients (4.9%). Medicaid-insured patients missed substantially more follow-up appointments overall (35% vs 23%) and more consecutive visits (1.9 vs 1.1) compared with privately insured patients. In an environment with adequate Medicaid reimbursement, eligible children have equal access to cochlear implantation, regardless of socioeconomic background. However, lower socioeconomic background is associated with higher rates of postoperative complications, worse follow-up compliance, and lower rates of sequential bilateral implantation, observed herein in Medicaid-insured patients. These findings present opportunities for cochlear implant centers to create programs to address such downstream disparities.

Benefit and predictive factors for speech perception outcomes in pediatric bilateral cochlear implant recipients.

PubMed

Chang, Young-Soo; Hong, Sung Hwa; Kim, Eun Yeon; Choi, Ji Eun; Chung, Won-Ho; Cho, Yang-Sun; Moon, Il Joon

2018-05-18

Despite recent advancement in the prediction of cochlear implant outcome, the benefit of bilateral procedures compared to bimodal stimulation and how we predict speech perception outcomes of sequential bilateral cochlear implant based on bimodal auditory performance in children remain unclear. This investigation was performed: (1) to determine the benefit of sequential bilateral cochlear implant and (2) to identify the associated factors for the outcome of sequential bilateral cochlear implant. Observational and retrospective study. We retrospectively analyzed 29 patients with sequential cochlear implant following bimodal-fitting condition. Audiological evaluations were performed; the categories of auditory performance scores, speech perception with monosyllable and disyllables words, and the Korean version of Ling. Audiological evaluations were performed before sequential cochlear implant with the bimodal fitting condition (CI1+HA) and one year after the sequential cochlear implant with bilateral cochlear implant condition (CI1+CI2). The good Performance Group (GP) was defined as follows; 90% or higher in monosyllable and bisyllable tests with auditory-only condition or 20% or higher improvement of the scores with CI1+CI2. Age at first implantation, inter-implant interval, categories of auditory performance score, and various comorbidities were analyzed by logistic regression analysis. Compared to the CI1+HA, CI1+CI2 provided significant benefit in categories of auditory performance, speech perception, and Korean version of Ling results. Preoperative categories of auditory performance scores were the only associated factor for being GP (odds ratio=4.38, 95% confidence interval - 95%=1.07-17.93, p=0.04). The children with limited language development in bimodal condition should be considered as the sequential bilateral cochlear implant and preoperative categories of auditory performance score could be used as the predictor in speech perception after sequential cochlear implant. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Selective Attention to Visual Stimuli Using Auditory Distractors Is Altered in Alpha-9 Nicotinic Receptor Subunit Knock-Out Mice.

PubMed

Terreros, Gonzalo; Jorratt, Pascal; Aedo, Cristian; Elgoyhen, Ana Belén; Delano, Paul H

2016-07-06

During selective attention, subjects voluntarily focus their cognitive resources on a specific stimulus while ignoring others. Top-down filtering of peripheral sensory responses by higher structures of the brain has been proposed as one of the mechanisms responsible for selective attention. A prerequisite to accomplish top-down modulation of the activity of peripheral structures is the presence of corticofugal pathways. The mammalian auditory efferent system is a unique neural network that originates in the auditory cortex and projects to the cochlear receptor through the olivocochlear bundle, and it has been proposed to function as a top-down filter of peripheral auditory responses during attention to cross-modal stimuli. However, to date, there is no conclusive evidence of the involvement of olivocochlear neurons in selective attention paradigms. Here, we trained wild-type and α-9 nicotinic receptor subunit knock-out (KO) mice, which lack cholinergic transmission between medial olivocochlear neurons and outer hair cells, in a two-choice visual discrimination task and studied the behavioral consequences of adding different types of auditory distractors. In addition, we evaluated the effects of contralateral noise on auditory nerve responses as a measure of the individual strength of the olivocochlear reflex. We demonstrate that KO mice have a reduced olivocochlear reflex strength and perform poorly in a visual selective attention paradigm. These results confirm that an intact medial olivocochlear transmission aids in ignoring auditory distraction during selective attention to visual stimuli. The auditory efferent system is a neural network that originates in the auditory cortex and projects to the cochlear receptor through the olivocochlear system. It has been proposed to function as a top-down filter of peripheral auditory responses during attention to cross-modal stimuli. However, to date, there is no conclusive evidence of the involvement of olivocochlear neurons in selective attention paradigms. Here, we studied the behavioral consequences of adding different types of auditory distractors in a visual selective attention task in wild-type and α-9 nicotinic receptor knock-out (KO) mice. We demonstrate that KO mice perform poorly in the selective attention paradigm and that an intact medial olivocochlear transmission aids in ignoring auditory distractors during attention. Copyright © 2016 the authors 0270-6474/16/367198-12$15.00/0.

Does a Flatter General Gradient of Visual Attention Explain Peripheral Advantages and Central Deficits in Deaf Adults?

PubMed Central

Samar, Vincent J.; Berger, Lauren

2017-01-01

Individuals deaf from early age often outperform hearing individuals in the visual periphery on attention-dependent dorsal stream tasks (e.g., spatial localization or movement detection), but sometimes show central visual attention deficits, usually on ventral stream object identification tasks. It has been proposed that early deafness adaptively redirects attentional resources from central to peripheral vision to monitor extrapersonal space in the absence of auditory cues, producing a more evenly distributed attention gradient across visual space. However, little direct evidence exists that peripheral advantages are functionally tied to central deficits, rather than determined by independent mechanisms, and previous studies using several attention tasks typically report peripheral advantages or central deficits, not both. To test the general altered attentional gradient proposal, we employed a novel divided attention paradigm that measured target localization performance along a gradient from parafoveal to peripheral locations, independent of concurrent central object identification performance in prelingually deaf and hearing groups who differed in access to auditory input. Deaf participants without cochlear implants (No-CI), with cochlear implants (CI), and hearing participants identified vehicles presented centrally, and concurrently reported the location of parafoveal (1.4°) and peripheral (13.3°) targets among distractors. No-CI participants but not CI participants showed a central identification accuracy deficit. However, all groups displayed equivalent target localization accuracy at peripheral and parafoveal locations and nearly parallel parafoveal-peripheral gradients. Furthermore, the No-CI group’s central identification deficit remained after statistically controlling peripheral performance; conversely, the parafoveal and peripheral group performance equivalencies remained after controlling central identification accuracy. These results suggest that, in the absence of auditory input, reduced central attentional capacity is not necessarily associated with enhanced peripheral attentional capacity or with flattening of a general attention gradient. Our findings converge with earlier studies suggesting that a general graded trade-off of attentional resources across the visual field does not adequately explain the complex task-dependent spatial distribution of deaf-hearing performance differences reported in the literature. Rather, growing evidence suggests that the spatial distribution of attention-mediated performance in deaf people is determined by sophisticated cross-modal plasticity mechanisms that recruit specific sensory and polymodal cortex to achieve specific compensatory processing goals. PMID:28559861

A comparison of speech intonation production and perception abilities of Farsi speaking cochlear implanted and normal hearing children.

PubMed

Moein, Narges; Khoddami, Seyyedeh Maryam; Shahbodaghi, Mohammad Rahim

2017-10-01

Cochlear implant prosthesis facilitates spoken language development and speech comprehension in children with severe-profound hearing loss. However, this prosthesis is limited in encoding information about fundamental frequency and pitch that are essentially for recognition of speech prosody. The purpose of the present study is to investigate the perception and production of intonation in cochlear implant children and comparison with normal hearing children. This study carried out on 25 cochlear implanted children and 50 children with normal hearing. First, using 10 action pictures statements and questions sentences were extracted. Fundamental frequency and pitch changes were identified using Praat software. Then, these sentences were judged by 7 adult listeners. In second stage 20 sentences were played for child and he/she determined whether it was in a question form or statement one. Performance of cochlear implanted children in perception and production of intonation was significantly lower than children with normal hearing. The difference between fundamental frequency and pitch changes in cochlear implanted children and children with normal hearing was significant (P < 0/05). Cochlear implanted children performance in perception and production of intonation has significant correlation with child's age surgery and duration of prosthesis use (P < 0/05). The findings of the current study show that cochlear prostheses have limited application in facilitating the perception and production of intonation in cochlear implanted children. It should be noted that the child's age at the surgery and duration of prosthesis's use is important in reduction of this limitation. According to these findings, speech and language pathologists should consider intervention of intonation in treatment program of cochlear implanted children. Copyright © 2017 Elsevier B.V. All rights reserved.

The Role of MRI in Diagnosing Neurovascular Compression of the Cochlear Nerve Resulting in Typewriter Tinnitus.

PubMed

Bae, Y J; Jeon, Y J; Choi, B S; Koo, J-W; Song, J-J

2017-06-01

Typewriter tinnitus, a symptom characterized by paroxysmal attacks of staccato sounds, has been thought to be caused by neurovascular compression of the cochlear nerve, but the correlation between radiologic evidence of neurovascular compression of the cochlear nerve and symptom presentation has not been thoroughly investigated. The purpose of this study was to examine whether radiologic evidence of neurovascular compression of the cochlear nerve is pathognomonic in typewriter tinnitus. Fifteen carbamazepine-responding patients with typewriter tinnitus and 8 control subjects were evaluated with a 3D T2-weighted volume isotropic turbo spin-echo acquisition sequence. Groups 1 (16 symptomatic sides), 2 (14 asymptomatic sides), and 3 (16 control sides) were compared with regard to the anatomic relation between the vascular loop and the internal auditory canal and the presence of neurovascular compression of the cochlear nerve with/without angulation/indentation. The anatomic location of the vascular loop was not significantly different among the 3 groups (all, P > .05). Meanwhile, neurovascular compression of the cochlear nerve on MR imaging was significantly higher in group 1 than in group 3 ( P = .032). However, considerable false-positive (no symptoms with neurovascular compression of the cochlear nerve on MR imaging) and false-negative (typewriter tinnitus without demonstrable neurovascular compression of the cochlear nerve) findings were also observed. Neurovascular compression of the cochlear nerve was more frequently detected on the symptomatic side of patients with typewriter tinnitus compared with the asymptomatic side of these patients or on both sides of control subjects on MR imaging. However, considering false-positive and false-negative findings, meticulous history-taking and the response to the initial carbamazepine trial should be regarded as more reliable diagnostic clues than radiologic evidence of neurovascular compression of the cochlear nerve. © 2017 by American Journal of Neuroradiology.

Auditory preferences of young children with and without hearing loss for meaningful auditory-visual compound stimuli.

PubMed

Zupan, Barbra; Sussman, Joan E

2009-01-01

Experiment 1 examined modality preferences in children and adults with normal hearing to combined auditory-visual stimuli. Experiment 2 compared modality preferences in children using cochlear implants participating in an auditory emphasized therapy approach to the children with normal hearing from Experiment 1. A second objective in both experiments was to evaluate the role of familiarity in these preferences. Participants were exposed to randomized blocks of photographs and sounds of ten familiar and ten unfamiliar animals in auditory-only, visual-only and auditory-visual trials. Results indicated an overall auditory preference in children, regardless of hearing status, and a visual preference in adults. Familiarity only affected modality preferences in adults who showed a strong visual preference to unfamiliar stimuli only. The similar degree of auditory responses in children with hearing loss to those from children with normal hearing is an original finding and lends support to an auditory emphasis for habilitation. Readers will be able to (1) Describe the pattern of modality preferences reported in young children without hearing loss; (2) Recognize that differences in communication mode may affect modality preferences in young children with hearing loss; and (3) Understand the role of familiarity in modality preferences in children with and without hearing loss.

Trends in cochlear implants.

PubMed

Zeng, Fan-Gang

2004-01-01

More than 60,000 people worldwide use cochlear implants as a means to restore functional hearing. Although individual performance variability is still high, an average implant user can talk on the phone in a quiet environment. Cochlear-implant research has also matured as a field, as evidenced by the exponential growth in both the patient population and scientific publication. The present report examines current issues related to audiologic, clinical, engineering, anatomic, and physiologic aspects of cochlear implants, focusing on their psychophysical, speech, music, and cognitive performance. This report also forecasts clinical and research trends related to presurgical evaluation, fitting protocols, signal processing, and postsurgical rehabilitation in cochlear implants. Finally, a future landscape in amplification is presented that requires a unique, yet complementary, contribution from hearing aids, middle ear implants, and cochlear implants to achieve a total solution to the entire spectrum of hearing loss treatment and management.

Response Properties of Cochlear Nucleus Neurons in Monkeys

PubMed Central

Roth, G. Linn; Recio, A.

2009-01-01

Much of what is known about how the cochlear nuclei participate in mammalian hearing comes from studies of non-primate mammalian species. To determine to what extent the cochlear nuclei of primates resemble those of other mammalian orders, we have recorded responses to sound in three primate species: marmosets, Cynomolgus macaques, and squirrel monkeys. These recordings show that the same types of temporal firing patterns are found in primates that have been described in other mammals. Responses to tones of neurons in the ventral cochlear nucleus have similar tuning, latencies, post-stimulus time and interspike interval histograms as those recorded in non-primate cochlear nucleus neurons. In the dorsal cochlear nucleus, too, responses were similar. From these results it is evident that insights gained from non-primate studies can be applied to the peripheral auditory system of primates. PMID:19531377

Comparison of Social Interaction between Cochlear-Implanted Children with Normal Intelligence Undergoing Auditory Verbal Therapy and Normal-Hearing Children: A Pilot Study.

PubMed

Monshizadeh, Leila; Vameghi, Roshanak; Sajedi, Firoozeh; Yadegari, Fariba; Hashemi, Seyed Basir; Kirchem, Petra; Kasbi, Fatemeh

2018-04-01

A cochlear implant is a device that helps hearing-impaired children by transmitting sound signals to the brain and helping them improve their speech, language, and social interaction. Although various studies have investigated the different aspects of speech perception and language acquisition in cochlear-implanted children, little is known about their social skills, particularly Persian-speaking cochlear-implanted children. Considering the growing number of cochlear implants being performed in Iran and the increasing importance of developing near-normal social skills as one of the ultimate goals of cochlear implantation, this study was performed to compare the social interaction between Iranian cochlear-implanted children who have undergone rehabilitation (auditory verbal therapy) after surgery and normal-hearing children. This descriptive-analytical study compared the social interaction level of 30 children with normal hearing and 30 with cochlear implants who were conveniently selected. The Raven test was administered to the both groups to ensure normal intelligence quotient. The social interaction status of both groups was evaluated using the Vineland Adaptive Behavior Scale, and statistical analysis was performed using Statistical Package for Social Sciences (SPSS) version 21. After controlling age as a covariate variable, no significant difference was observed between the social interaction scores of both the groups (p > 0.05). In addition, social interaction had no correlation with sex in either group. Cochlear implantation followed by auditory verbal rehabilitation helps children with sensorineural hearing loss to have normal social interactions, regardless of their sex.

Effects of residual hearing on cochlear implant outcomes in children: A systematic-review.

PubMed

Chiossi, Julia Santos Costa; Hyppolito, Miguel Angelo

2017-09-01

to investigate if preoperative residual hearing in prelingually deafened children can interfere on cochlear implant indication and outcomes. a systematic-review was conducted in five international databases up to November-2016, to locate articles that evaluated cochlear implantation in children with some degree of preoperative residual hearing. Outcomes were auditory, language and cognition performances after cochlear implant. The quality of the studies was assessed and classified according to the Oxford Levels of Evidence table - 2011. Risk of biases were also described. From the 30 articles reviewed, two types of questions were identified: (a) what are the benefits of cochlear implantation in children with residual hearing? (b) is the preoperative residual hearing a predictor of cochlear implant outcome? Studies ranged from 04 to 188 subjects, evaluating populations between 1.8 and 10.3 years old. The definition of residual hearing varied between studies. The majority of articles (n = 22) evaluated speech perception as the outcome and 14 also assessed language and speech production. There is evidence that cochlear implant is beneficial to children with residual hearing. Preoperative residual hearing seems to be valuable to predict speech perception outcomes after cochlear implantation, even though the mechanism of how it happens is not clear. More extensive researches must be conducted in order to make recommendations and to set prognosis for cochlear implants based on children preoperative residual hearing. Copyright © 2017 Elsevier B.V. All rights reserved.

Internet Video Telephony Allows Speech Reading by Deaf Individuals and Improves Speech Perception by Cochlear Implant Users

PubMed Central

Mantokoudis, Georgios; Dähler, Claudia; Dubach, Patrick; Kompis, Martin; Caversaccio, Marco D.; Senn, Pascal

2013-01-01

Objective To analyze speech reading through Internet video calls by profoundly hearing-impaired individuals and cochlear implant (CI) users. Methods Speech reading skills of 14 deaf adults and 21 CI users were assessed using the Hochmair Schulz Moser (HSM) sentence test. We presented video simulations using different video resolutions (1280×720, 640×480, 320×240, 160×120 px), frame rates (30, 20, 10, 7, 5 frames per second (fps)), speech velocities (three different speakers), webcameras (Logitech Pro9000, C600 and C500) and image/sound delays (0–500 ms). All video simulations were presented with and without sound and in two screen sizes. Additionally, scores for live Skype™ video connection and live face-to-face communication were assessed. Results Higher frame rate (>7 fps), higher camera resolution (>640×480 px) and shorter picture/sound delay (<100 ms) were associated with increased speech perception scores. Scores were strongly dependent on the speaker but were not influenced by physical properties of the camera optics or the full screen mode. There is a significant median gain of +8.5%pts (p = 0.009) in speech perception for all 21 CI-users if visual cues are additionally shown. CI users with poor open set speech perception scores (n = 11) showed the greatest benefit under combined audio-visual presentation (median speech perception +11.8%pts, p = 0.032). Conclusion Webcameras have the potential to improve telecommunication of hearing-impaired individuals. PMID:23359119

Use of suprathreshold stochastic resonance in cochlear implant coding

NASA Astrophysics Data System (ADS)

Allingham, David; Stocks, Nigel G.; Morse, Robert P.

2003-05-01

In this article we discuss the possible use of a novel form of stochastic resonance, termed suprathreshold stochastic resonance (SSR), to improve signal encoding/transmission in cochlear implants. A model, based on the leaky-integrate-and-fire (LIF) neuron, has been developed from physiological data and use to model information flow in a population of cochlear nerve fibers. It is demonstrated that information flow can, in principle, be enhanced by the SSR effect. Furthermore, SSR was found to enhance information transmission for signal parameters that are commonly encountered in cochlear implants. This, therefore, gives hope that SSR may be implemented in cochlear implants to improve speech comprehension.

Round-window delivery of neurotrophin 3 regenerates cochlear synapses after acoustic overexposure.

PubMed

Suzuki, Jun; Corfas, Gabriel; Liberman, M Charles

2016-04-25

In acquired sensorineural hearing loss, such as that produced by noise or aging, there can be massive loss of the synaptic connections between cochlear sensory cells and primary sensory neurons, without loss of the sensory cells themselves. Because the cell bodies and central projections of these cochlear neurons survive for months to years, there is a long therapeutic window in which to re-establish functional connections and improve hearing ability. Here we show in noise-exposed mice that local delivery of neurotrophin-3 (NT-3) to the round window niche, 24 hours after an exposure that causes an immediate loss of up to 50% loss of synapses in the cochlear basal region, can regenerate pre- and post-synaptic elements at the hair cell / cochlear nerve interface. This synaptic regeneration, as documented by confocal microscopy of immunostained cochlear sensory epithelia, was coupled with a corresponding functional recovery, as seen in the suprathreshold amplitude of auditory brainstem response Wave 1. Cochlear delivery of neurotrophins in humans is likely achievable as an office procedure via transtympanic injection, making our results highly significant in a translational context.

Prevention of Noise Damage to Cochlear Synapses

DTIC Science & Technology

2015-10-01

AWARD NUMBER: W81XWH-14-1-0494 TITLE: Prevention of Noise Damage to Cochlear Synapses PRINCIPAL INVESTIGATOR: Steven Green CONTRACTING...to Cochlear Synapses 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-14-1-0494 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Steven Green 5d. PROJECT...ABSTRACT Noise-induced synaptopathy is the result of excitotoxic trauma to cochlear synapses due to glutamate released from the hair cells. Excitotoxic

Preventing Ototoxic Synergy of Prior Noise Trauma During Aminoglycoside Therapy

DTIC Science & Technology

2015-12-01

cochlear blood flow . Hearing Research 313, 38-46 (2014). 12. Koo, J.-W. et al. Endotoxemia-mediated inflammation potentiates cochlear uptake of...event in response to a need for higher cochlear blood flow . A 3.7% dilation was adequate for a 20% increase of blood flow 10. On the contrary...summation of the two insults. We have found that prior sound exposure enhances cochlear uptake of aminoglycosides, providing a mechanistic basis for the

Scala vestibuli cochlear implantation in patients with partially ossified cochleas.

PubMed

Berrettini, Stefano; Forli, Francesca; Neri, Emanuele; Segnini, Giovanni; Franceschini, Stefano Sellari

2002-11-01

Partial cochlear obstruction is a relatively common finding in candidates for cochlear implants and frequently involves the inferior segment of the scala tympani in the basal turn of the cochlea. In such patients, the scala vestibuli is often patent and offers an alternative site for implantation. The current report describes two patients with such partial obstruction of the inferior segment of the basal cochlear turn, caused in one case by systemic vasculitis (Takayasu's disease) and in the other by obliterative otosclerosis. A scala vestibuli implantation allowed for complete insertion of the electrode array. No problems were encountered during the surgical procedures and the good post-operative hearing and communicative outcomes achieved were similar to those reported in patients without cochlear ossification. The importance of accurate pre-operative radiological study of the inner ear is underscored, to disclose the presence and define the features of the cochlear ossification and ultimately to properly plan the surgical approach.

Hearing rehabilitation with a binaural cochlear implant in a patient with Erdheim-Chester disease.

PubMed

Querat, Charlotte; Thai-Van, Hung; Durand, Denis Vital; Cotton, François; Gallego, Stéphane; Truy, Eric

2015-09-01

Erdheim-Chester disease (ECD) is a rare non-Langerhans form of histiocytosis. This paper reports an exceptional case of bilateral neural involvement, responsible for profound hearing loss. Bilateral cochlear implantation was performed. We present a 57-year-old man affected by ECD with profound bilateral hearing loss. The patient underwent cochlear implantation with a binaural Digisonic(®) cochlear implant, 7 years after the initial diagnosis. Speech intelligibility rose to a plateau after about 6 months of cochlear implant use. The average outcome of speech intelligibility over time was 55% for dissyllabic words without lip reading, and 70% for sentences. Perception score decreased before the patient died from ECD. A description of the ECD and its otological manifestations is presented. This paper reports the effective hearing rehabilitation of profound bilateral hearing loss by the means of a binaural Digisonic(®) cochlear implant.

Spiral Form of the Human Cochlea Results from Spatial Constraints.

PubMed

Pietsch, M; Aguirre Dávila, L; Erfurt, P; Avci, E; Lenarz, T; Kral, A

2017-08-08

The human inner ear has an intricate spiral shape often compared to shells of mollusks, particularly to the nautilus shell. It has inspired many functional hearing theories. The reasons for this complex geometry remain unresolved. We digitized 138 human cochleae at microscopic resolution and observed an astonishing interindividual variability in the shape. A 3D analytical cochlear model was developed that fits the analyzed data with high precision. The cochlear geometry neither matched a proposed function, namely sound focusing similar to a whispering gallery, nor did it have the form of a nautilus. Instead, the innate cochlear blueprint and its actual ontogenetic variants were determined by spatial constraints and resulted from an efficient packing of the cochlear duct within the petrous bone. The analytical model predicts well the individual 3D cochlear geometry from few clinical measures and represents a clinical tool for an individualized approach to neurosensory restoration with cochlear implants.

Trends in Cochlear Implants

PubMed Central

Zeng, Fan-Gang

2004-01-01

More than 60,000 people worldwide use cochlear implants as a means to restore functional hearing. Although individual performance variability is still high, an average implant user can talk on the phone in a quiet environment. Cochlear-implant research has also matured as a field, as evidenced by the exponential growth in both the patient population and scientific publication. The present report examines current issues related to audiologic, clinical, engineering, anatomic, and physiologic aspects of cochlear implants, focusing on their psychophysical, speech, music, and cognitive performance. This report also forecasts clinical and research trends related to presurgical evaluation, fitting protocols, signal processing, and postsurgical rehabilitation in cochlear implants. Finally, a future landscape in amplification is presented that requires a unique, yet complementary, contribution from hearing aids, middle ear implants, and cochlear implants to achieve a total solution to the entire spectrum of hearing loss treatment and management. PMID:15247993

Ion flow in cochlear hair cells and the regulation of hearing sensitivity.

PubMed

Patuzzi, Robert

2011-10-01

This paper discusses how ion transport proteins in the hair cells of the mammalian cochlea work to produce a sensitive but stable hearing organ. The transport proteins in the inner and outer hair cells are summarized (including their current voltage characteristics), and the roles of these proteins in determining intracellular Ca(2+), membrane potential, and ultimately cochlear sensitivity are discussed. The paper also discusses the role of the Ca(2+) sequestration sacs in outer hair cells in the autoregulation of hair cell membrane potential and cochlear gain, and how the underdamped control of Ca(2+) within these sacs may produce the observed slow oscillations in cochlear sensitivity and otoacoustic emissions after cochlear perturbations, including perilymphatic perfusions and prolonged low-frequency tones. The relative insensitivity of cochlear gain to short-term changes in the endocochlear potential is also discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

The Hearing Outcomes of Cochlear Implantation in Waardenburg Syndrome.

PubMed

Koyama, Hajime; Kashio, Akinori; Sakata, Aki; Tsutsumiuchi, Katsuhiro; Matsumoto, Yu; Karino, Shotaro; Kakigi, Akinobu; Iwasaki, Shinichi; Yamasoba, Tatsuya

2016-01-01

Objectives. This study aimed to determine the feasibility of cochlear implantation for sensorineural hearing loss in patients with Waardenburg syndrome. Method. A retrospective chart review was performed on patients who underwent cochlear implantation at the University of Tokyo Hospital. Clinical classification, genetic mutation, clinical course, preoperative hearing threshold, high-resolution computed tomography of the temporal bone, and postoperative hearing outcome were assessed. Result. Five children with Waardenburg syndrome underwent cochlear implantation. The average age at implantation was 2 years 11 months (ranging from 1 year 9 months to 6 years 3 months). Four patients had congenital profound hearing loss and one patient had progressive hearing loss. Two patients had an inner ear malformation of cochlear incomplete partition type 2. No surgical complication or difficulty was seen in any patient. All patients showed good hearing outcome postoperatively. Conclusion. Cochlear implantation could be a good treatment option for Waardenburg syndrome.

The Hearing Outcomes of Cochlear Implantation in Waardenburg Syndrome

PubMed Central

Koyama, Hajime; Kashio, Akinori; Sakata, Aki; Tsutsumiuchi, Katsuhiro; Matsumoto, Yu; Karino, Shotaro; Kakigi, Akinobu; Iwasaki, Shinichi; Yamasoba, Tatsuya

2016-01-01

Objectives. This study aimed to determine the feasibility of cochlear implantation for sensorineural hearing loss in patients with Waardenburg syndrome. Method. A retrospective chart review was performed on patients who underwent cochlear implantation at the University of Tokyo Hospital. Clinical classification, genetic mutation, clinical course, preoperative hearing threshold, high-resolution computed tomography of the temporal bone, and postoperative hearing outcome were assessed. Result. Five children with Waardenburg syndrome underwent cochlear implantation. The average age at implantation was 2 years 11 months (ranging from 1 year 9 months to 6 years 3 months). Four patients had congenital profound hearing loss and one patient had progressive hearing loss. Two patients had an inner ear malformation of cochlear incomplete partition type 2. No surgical complication or difficulty was seen in any patient. All patients showed good hearing outcome postoperatively. Conclusion. Cochlear implantation could be a good treatment option for Waardenburg syndrome. PMID:27376080

Should children who use cochlear implants wear hearing aids in the opposite ear?

PubMed

Ching, T Y; Psarros, C; Hill, M; Dillon, H; Incerti, P

2001-10-01

The aim of this study was to investigate 1) whether a hearing aid needs to be adjusted differently depending on whether a child wears a cochlear implant or another hearing aid in the contralateral ear; 2) whether the use of a hearing aid and a cochlear implant in opposite ears leads to binaural interference; and 3) whether the use of a hearing aid and a cochlear implant in opposite ears leads to binaural benefits in speech perception, localization, and communicative functioning in real life. Sixteen children participated in this study. All children used a Nucleus 22 or Nucleus 24 cochlear implant system programmed with the SPEAK strategy in one ear. The hearing aid amplification requirements in the nonimplanted ear of these children were determined using two procedures. A paired comparison technique was used to identify the frequency response that was best for speech intelligibility in quiet, and a loudness balancing technique was used to match the loudness of speech in the ear with a hearing aid to that with a cochlear implant. Eleven of the 16 children participated in the investigation of binaural effects. Performance in speech perception, localization, and communicative functioning was assessed under four aided conditions: cochlear implant with hearing aid as worn, cochlear implant alone, hearing aid alone, and cochlear implant with hearing aid adjusted according to individual requirements. Fifteen of the 16 children whose amplification requirements were determined preferred a hearing aid frequency response that was within +/-6 dB/octave of the NAL-RP prescription. On average, the children required 6 dB more gain than prescribed to balance the loudness of the implanted ear for a speech signal presented at 65 dB SPL. For all 11 children whose performance was evaluated for investigating binaural effects, there was no indication of significantly poorer performance under bilaterally aided conditions compared with unilaterally aided conditions. On average, there were significant benefits in speech perception, localization, and aural/oral function when the children used cochlear implants with adjusted hearing aids than when they used cochlear implants alone. All individuals showed benefits in at least one of the measures. Hearing aids for children who also use cochlear implants can be selected using the NAL-RP prescription. Adjustment of hearing aid gain to match loudness in the implanted ear can facilitate integration of signals from both ears, leading to better speech perception. Given that there are binaural advantages from using cochlear implants with hearing aids in opposite ears, clinicians should advise parents and other professionals about these potential advantages, and facilitate bilateral amplification by adjusting hearing aids after stable cochlear implant MAPs are established.

Effects of central nervous system residua on cochlear implant results in children deafened by meningitis.

PubMed

Francis, Howard W; Pulsifer, Margaret B; Chinnici, Jill; Nutt, Robert; Venick, Holly S; Yeagle, Jennifer D; Niparko, John K

2004-05-01

This study explored factors associated with speech recognition outcomes in postmeningitic deafness (PMD). The results of cochlear implantation may vary in children with PMD because of sequelae that extend beyond the auditory periphery. To determine which factors might be most determinative of outcome of cochlear implantation in children with PMD. Retrospective chart review. A referral center for pediatric cochlear implantation and rehabilitation. Thirty children with cochlear implants who were deafened by meningitis were matched with subjects who were deafened by other causes based on the age at diagnosis, age at cochlear implantation, age at which hearing aids were first used, and method of communication used at home or in the classroom. Speech perception performance within the first 2 years after cochlear implantation and its relationship with presurgical cognitive measures and medical history. There was no difference in the overall cognitive or postoperative speech perception performance between the children with PMD and those deafened by other causes. The presence of postmeningitic hydrocephalus, however, posed greater challenges to the rehabilitation process, as indicated by significantly smaller gains in speech perception and a predilection for behavioral problems. By comparison, cochlear scarring and incomplete electrode insertion had no impact on speech perception results. Although the results demonstrated no significant delay in cognitive or speech perception performance in the PMD group, central nervous system residua, when present, can impede the acquisition of speech perception with a cochlear implant. Central effects associated with PMD may thus impact language learning potential; cognitive and behavioral therapy should be considered in rehabilitative planning and in establishing expectations of outcome.

A Preliminary Investigation of the Air-Bone Gap: Changes in Intracochlear Sound Pressure With Air- and Bone-conducted Stimuli After Cochlear Implantation.

PubMed

Banakis Hartl, Renee M; Mattingly, Jameson K; Greene, Nathaniel T; Jenkins, Herman A; Cass, Stephen P; Tollin, Daniel J

2016-10-01

A cochlear implant electrode within the cochlea contributes to the air-bone gap (ABG) component of postoperative changes in residual hearing after electrode insertion. Preservation of residual hearing after cochlear implantation has gained importance as simultaneous electric-acoustic stimulation allows for improved speech outcomes. Postoperative loss of residual hearing has previously been attributed to sensorineural changes; however, presence of increased postoperative ABG remains unexplained and could result in part from altered cochlear mechanics. Here, we sought to investigate changes to these mechanics via intracochlear pressure measurements before and after electrode implantation to quantify the contribution to postoperative ABG. Human cadaveric heads were implanted with titanium fixtures for bone conduction transducers. Velocities of stapes capitulum and cochlear promontory between the two windows were measured using single-axis laser Doppler vibrometry and fiber-optic sensors measured intracochlear pressures in scala vestibuli and tympani for air- and bone-conducted stimuli before and after cochlear implant electrode insertion through the round window. Intracochlear pressures revealed only slightly reduced responses to air-conducted stimuli consistent with previous literature. No significant changes were noted to bone-conducted stimuli after implantation. Velocities of the stapes capitulum and the cochlear promontory to both stimuli were stable after electrode placement. Presence of a cochlear implant electrode causes alterations in intracochlear sound pressure levels to air, but not bone, conducted stimuli and helps to explain changes in residual hearing noted clinically. These results suggest the possibility of a cochlear conductive component to postoperative changes in hearing sensitivity.

Effect of 5-hydroxytryptamine on the respiration of excised lamellibranch gill.

PubMed

MOORE, K E; MILTON, A S; GOSSELIN, R E

1961-10-01

5-Hydroxytryptamine, but not acetylcholine or catecholamines, stimulated the endogenous respiration of the excised gills of Modiolus demissus and mytilus edulis. Respiratory stimulation by 5-hydroxytryptophan is presumed to have occurred only after it had been decarboxylated to 5-hydroxytryptamine. 2-Bromolysergic acid diethylamide inhibited the effect of 5-hydroxytryptamine, while lysergic acid diethylamide mimicked it. The glycogen that was degraded during incubation of the gill cannot account for all of the oxygen that was consumed, indicating that some other substrate within the gill was also oxidized. That the metabolic actions of 5-hydroxytryptamine may be related to its cilio-acceleratory activity is discussed.

Cochlear implants in Waardenburg syndrome.

PubMed

Cullen, Robert D; Zdanski, Carlton; Roush, Patricia; Brown, Carolyn; Teagle, Holly; Pillsbury, Harold C; Buchman, Craig

2006-07-01

Waardenburg syndrome is an autosomal-dominant syndrome characterized by dystopia canthorum, hyperplasia of the eyebrows, heterochromia irides, a white forelock, and sensorineural hearing loss in 20% to 55% of patients. This patient population accounts for approximately 2% of congenitally deaf children. The purpose of this retrospective case review was to describe the outcomes for those children with Waardenburg syndrome who have undergone cochlear implantation. Pediatric cochlear implant recipients with documented evidence of Waardenburg syndrome underwent retrospective case review. All patients received their cochlear implants at the study institution followed by outpatient auditory habilitation. Charts were reviewed for etiology and duration of deafness, age at time of cochlear implantation, perioperative complications, duration of use, and performance outcomes. Results of standard tests batteries for speech perception and production administered as a part of the patients' auditory habilitation were reviewed. Seven patients with Waardenburg syndrome and cochlear implants were identified. The average age at implantation was 37 months (range, 18-64 months) and the average duration of use was 69 months (range, 12-143 months). All of these patients are active users of their devices and perform very well after implantation. There were no major complications in this small group of patients. Children with congenital sensorineural hearing loss without other comorbidities (e.g., developmental delay, inner ear malformations) perform well when they receive cochlear implantation and auditory habilitation. Patients with Waardenburg syndrome can be expected to have above-average performance after cochlear implantation.

Surgical Management of the Pediatric Cochlear Implant Patient.

ERIC Educational Resources Information Center

Cohen, Seth M.; Haynes, David S.

2003-01-01

This article discusses the surgical management of children receiving cochlear implants. It identifies preoperative considerations to select patients likely to benefit, contraindications, some new surgical techniques, complications, special considerations (otitis media, meningitis, head growth, inner ear malformations, and cochlear obstruction).…

Benefits of music training in mandarin-speaking pediatric cochlear implant users.

PubMed

Fu, Qian-Jie; Galvin, John J; Wang, Xiaosong; Wu, Jiunn-Liang

2015-02-01

The aims of this study were to assess young (5- to 10-year-old) Mandarin-speaking cochlear implant (CI) users' musical pitch perception and to assess the benefits of computer-based home training on performance. Melodic contour identification (MCI) was used to assess musical pitch perception in 14 Mandarin-speaking pediatric CI users; the instrument timbre and the contour length were varied as experimental parameters. Six subjects received subsequent MCI training on their home computer in which auditory and visual feedback were provided. MCI performance was generally poor (grand mean=33.3% correct) and highly variable, with scores ranging from 9.3% to 98.1% correct; there was no significant effect of instrument timbre or contour length on performance (p>.05). After 4 weeks of training, performance sharply improved. Follow-up measures that were conducted 8 weeks after training was stopped showed no significant decline in MCI performance. For the 6 trained subjects, there was a significant effect of contour length for the training and follow-up measures. These preliminary data suggest that although baseline MCI performance initially may be poor, training may greatly improve Mandarin-speaking pediatric CI users' melodic pitch perception.

Perceptual Learning and Auditory Training in Cochlear Implant Recipients

PubMed Central

Fu, Qian-Jie; Galvin, John J.

2007-01-01

Learning electrically stimulated speech patterns can be a new and difficult experience for cochlear implant (CI) recipients. Recent studies have shown that most implant recipients at least partially adapt to these new patterns via passive, daily-listening experiences. Gradually introducing a speech processor parameter (eg, the degree of spectral mismatch) may provide for more complete and less stressful adaptation. Although the implant device restores hearing sensation and the continued use of the implant provides some degree of adaptation, active auditory rehabilitation may be necessary to maximize the benefit of implantation for CI recipients. Currently, there are scant resources for auditory rehabilitation for adult, postlingually deafened CI recipients. We recently developed a computer-assisted speech-training program to provide the means to conduct auditory rehabilitation at home. The training software targets important acoustic contrasts among speech stimuli, provides auditory and visual feedback, and incorporates progressive training techniques, thereby maintaining recipients’ interest during the auditory training exercises. Our recent studies demonstrate the effectiveness of targeted auditory training in improving CI recipients’ speech and music perception. Provided with an inexpensive and effective auditory training program, CI recipients may find the motivation and momentum to get the most from the implant device. PMID:17709574

Concept Formation Skills in Long-Term Cochlear Implant Users

PubMed Central

Castellanos, Irina; Kronenberger, William G.; Beer, Jessica; Colson, Bethany G.; Henning, Shirley C.; Ditmars, Allison; Pisoni, David B.

2015-01-01

This study investigated if a period of auditory sensory deprivation followed by degraded auditory input and related language delays affects visual concept formation skills in long-term prelingually deaf cochlear implant (CI) users. We also examined if concept formation skills are mediated or moderated by other neurocognitive domains (i.e., language, working memory, and executive control). Relative to normally hearing (NH) peers, CI users displayed significantly poorer performance in several specific areas of concept formation, especially when multiple comparisons and relational concepts were components of the task. Differences in concept formation between CI users and NH peers were fully explained by differences in language and inhibition–concentration skills. Language skills were also found to be more strongly related to concept formation in CI users than in NH peers. The present findings suggest that complex relational concepts may be adversely affected by a period of early prelingual deafness followed by access to underspecified and degraded sound patterns and spoken language transmitted by a CI. Investigating a unique clinical population such as early-implanted prelingually deaf children with CIs can provide new insights into foundational brain–behavior relations and developmental processes. PMID:25583706

Selecting electrode configurations for image-guided cochlear implant programming using template matching.

PubMed

Zhang, Dongqing; Zhao, Yiyuan; Noble, Jack H; Dawant, Benoit M

2018-04-01

Cochlear implants (CIs) are neural prostheses that restore hearing using an electrode array implanted in the cochlea. After implantation, the CI processor is programmed by an audiologist. One factor that negatively impacts outcomes and can be addressed by programming is cross-electrode neural stimulation overlap (NSO). We have proposed a system to assist the audiologist in programming the CI that we call image-guided CI programming (IGCIP). IGCIP permits using CT images to detect NSO and recommend deactivation of a subset of electrodes to avoid NSO. We have shown that IGCIP significantly improves hearing outcomes. Most of the IGCIP steps are robustly automated but electrode configuration selection still sometimes requires manual intervention. With expertise, distance-versus-frequency curves, which are a way to visualize the spatial relationship learned from CT between the electrodes and the nerves they stimulate, can be used to select the electrode configuration. We propose an automated technique for electrode configuration selection. A comparison between this approach and one we have previously proposed shows that our method produces results that are as good as those obtained with our previous method while being generic and requiring fewer parameters.

Investigating the role of radixin in modulation of stereocilia length and stiffness

NASA Astrophysics Data System (ADS)

Prasad, Sonal; Fridberger, Anders

2018-05-01

Mammalian hearing depends on deflection of stereocilia on the sensory outer hair cells of the inner ear. Previous data indicate that the stiffness of outer hair cell stereocilia are actively regulated. The molecular mechanism that regulate the deflection of stereocilia are presently less known. The aim of the study is to investigate the mechanistic pathway that underlie the stiffness modulation of outer hair cell stereocilia. Our hypothesis is that the membrane-cytoskeleton linker protein radixin, which is present at high concentration in stereocilia, could contribute to stiffness regulation. To test this hypothesis, we use the radixin blocker DX-52-1 which binds strongly and specifically to radixin. Time-resolved confocal imaging was used to visualize the sound-evoked motion of stereocilia in a semi-intact preparation of the guinea pig temporal bone. Cochlear microphonic potentials were also measured, using electrodes positioned in scala media. We found that the DX-52-1 inhibitor leads to an increase in stereocilia movements and decline in the amplitude of the cochlear microphonic potential. However, DX-52-1 caused a paradoxical increase in electromotility. These results suggest that radixin has a functionally important regulatory role in the mature inner ear.

Benefits of Localization and Speech Perception with Multiple Noise Sources in Listeners with a Short-electrode Cochlear Implant

PubMed Central

Dunn, Camille C.; Perreau, Ann; Gantz, Bruce; Tyler, Richard

2009-01-01

Background Research suggests that for individuals with significant low-frequency hearing, implantation of a short-electrode cochlear implant may provide benefits of improved speech perception abilities. Because this strategy combines acoustic and electrical hearing within the same ear while at the same time preserving low-frequency residual acoustic hearing in both ears, localization abilities may also be improved. However, very little research has focused on the localization and spatial hearing abilities of users with a short-electrode cochlear implant. Purpose The purpose of this study was to evaluate localization abilities for listeners with a short-electrode cochlear implant who continue to wear hearing aids in both ears. A secondary purpose was to document speech perception abilities using a speech in noise test with spatially-separate noise sources. Research Design Eleven subjects that utilized a short-electrode cochlear implant and bilateral hearing aids were tested on localization and speech perception with multiple noise locations using an eight-loudspeaker array. Performance was assessed across four listening conditions using various combinations of cochlear implant and/or hearing aid use. Results Results for localization showed no significant difference between using bilateral hearing aids and bilateral hearing aids plus the cochlear implant. However, there was a significant difference between the bilateral hearing aid condition and the implant plus use of a contralateral hearing aid for all eleven subjects. Results for speech perception showed a significant benefit when using bilateral hearing aids plus the cochlear implant over use of the implant plus only one hearing aid. Conclusion Combined use of both hearing aids and the cochlear implant show significant benefits for both localization and speech perception in noise for users with a short-electrode cochlear implant. These results emphasize the importance of low-frequency information in two ears for the purpose of localization and speech perception in noise. PMID:20085199

Benefits of localization and speech perception with multiple noise sources in listeners with a short-electrode cochlear implant.

PubMed

Dunn, Camille C; Perreau, Ann; Gantz, Bruce; Tyler, Richard S

2010-01-01

Research suggests that for individuals with significant low-frequency hearing, implantation of a short-electrode cochlear implant may provide benefits of improved speech perception abilities. Because this strategy combines acoustic and electrical hearing within the same ear while at the same time preserving low-frequency residual acoustic hearing in both ears, localization abilities may also be improved. However, very little research has focused on the localization and spatial hearing abilities of users with a short-electrode cochlear implant. The purpose of this study was to evaluate localization abilities for listeners with a short-electrode cochlear implant who continue to wear hearing aids in both ears. A secondary purpose was to document speech perception abilities using a speech-in-noise test with spatially separate noise sources. Eleven subjects that utilized a short-electrode cochlear implant and bilateral hearing aids were tested on localization and speech perception with multiple noise locations using an eight-loudspeaker array. Performance was assessed across four listening conditions using various combinations of cochlear implant and/or hearing aid use. Results for localization showed no significant difference between using bilateral hearing aids and bilateral hearing aids plus the cochlear implant. However, there was a significant difference between the bilateral hearing aid condition and the implant plus use of a contralateral hearing aid for all 11 subjects. Results for speech perception showed a significant benefit when using bilateral hearing aids plus the cochlear implant over use of the implant plus only one hearing aid. Combined use of both hearing aids and the cochlear implant show significant benefits for both localization and speech perception in noise for users with a short-electrode cochlear implant. These results emphasize the importance of low-frequency information in two ears for the purpose of localization and speech perception in noise.

Benefits of Music Training for Perception of Emotional Speech Prosody in Deaf Children With Cochlear Implants

PubMed Central

Gordon, Karen A.; Papsin, Blake C.; Nespoli, Gabe; Hopyan, Talar; Peretz, Isabelle; Russo, Frank A.

2017-01-01

Objectives: Children who use cochlear implants (CIs) have characteristic pitch processing deficits leading to impairments in music perception and in understanding emotional intention in spoken language. Music training for normal-hearing children has previously been shown to benefit perception of emotional prosody. The purpose of the present study was to assess whether deaf children who use CIs obtain similar benefits from music training. We hypothesized that music training would lead to gains in auditory processing and that these gains would transfer to emotional speech prosody perception. Design: Study participants were 18 child CI users (ages 6 to 15). Participants received either 6 months of music training (i.e., individualized piano lessons) or 6 months of visual art training (i.e., individualized painting lessons). Measures of music perception and emotional speech prosody perception were obtained pre-, mid-, and post-training. The Montreal Battery for Evaluation of Musical Abilities was used to measure five different aspects of music perception (scale, contour, interval, rhythm, and incidental memory). The emotional speech prosody task required participants to identify the emotional intention of a semantically neutral sentence under audio-only and audiovisual conditions. Results: Music training led to improved performance on tasks requiring the discrimination of melodic contour and rhythm, as well as incidental memory for melodies. These improvements were predominantly found from mid- to post-training. Critically, music training also improved emotional speech prosody perception. Music training was most advantageous in audio-only conditions. Art training did not lead to the same improvements. Conclusions: Music training can lead to improvements in perception of music and emotional speech prosody, and thus may be an effective supplementary technique for supporting auditory rehabilitation following cochlear implantation. PMID:28085739

Benefits of Music Training for Perception of Emotional Speech Prosody in Deaf Children With Cochlear Implants.

PubMed

Good, Arla; Gordon, Karen A; Papsin, Blake C; Nespoli, Gabe; Hopyan, Talar; Peretz, Isabelle; Russo, Frank A

Children who use cochlear implants (CIs) have characteristic pitch processing deficits leading to impairments in music perception and in understanding emotional intention in spoken language. Music training for normal-hearing children has previously been shown to benefit perception of emotional prosody. The purpose of the present study was to assess whether deaf children who use CIs obtain similar benefits from music training. We hypothesized that music training would lead to gains in auditory processing and that these gains would transfer to emotional speech prosody perception. Study participants were 18 child CI users (ages 6 to 15). Participants received either 6 months of music training (i.e., individualized piano lessons) or 6 months of visual art training (i.e., individualized painting lessons). Measures of music perception and emotional speech prosody perception were obtained pre-, mid-, and post-training. The Montreal Battery for Evaluation of Musical Abilities was used to measure five different aspects of music perception (scale, contour, interval, rhythm, and incidental memory). The emotional speech prosody task required participants to identify the emotional intention of a semantically neutral sentence under audio-only and audiovisual conditions. Music training led to improved performance on tasks requiring the discrimination of melodic contour and rhythm, as well as incidental memory for melodies. These improvements were predominantly found from mid- to post-training. Critically, music training also improved emotional speech prosody perception. Music training was most advantageous in audio-only conditions. Art training did not lead to the same improvements. Music training can lead to improvements in perception of music and emotional speech prosody, and thus may be an effective supplementary technique for supporting auditory rehabilitation following cochlear implantation.

Intra- and Interobserver Variability of Cochlear Length Measurements in Clinical CT.

PubMed

Iyaniwura, John E; Elfarnawany, Mai; Riyahi-Alam, Sadegh; Sharma, Manas; Kassam, Zahra; Bureau, Yves; Parnes, Lorne S; Ladak, Hanif M; Agrawal, Sumit K

2017-07-01

The cochlear A-value measurement exhibits significant inter- and intraobserver variability, and its accuracy is dependent on the visualization method in clinical computed tomography (CT) images of the cochlea. An accurate estimate of the cochlear duct length (CDL) can be used to determine electrode choice, and frequency map the cochlea based on the Greenwood equation. Studies have described estimating the CDL using a single A-value measurement, however the observer variability has not been assessed. Clinical and micro-CT images of 20 cadaveric cochleae were acquired. Four specialists measured A-values on clinical CT images using both standard views and multiplanar reconstructed (MPR) views. Measurements were repeated to assess for intraobserver variability. Observer variabilities were evaluated using intra-class correlation and absolute differences. Accuracy was evaluated by comparison to the gold standard micro-CT images of the same specimens. Interobserver variability was good (average absolute difference: 0.77 ± 0.42 mm) using standard views and fair (average absolute difference: 0.90 ± 0.31 mm) using MPR views. Intraobserver variability had an average absolute difference of 0.31 ± 0.09 mm for the standard views and 0.38 ± 0.17 mm for the MPR views. MPR view measurements were more accurate than standard views, with average relative errors of 9.5 and 14.5%, respectively. There was significant observer variability in A-value measurements using both the standard and MPR views. Creating the MPR views increased variability between experts, however MPR views yielded more accurate results. Automated A-value measurement algorithms may help to reduce variability and increase accuracy in the future.

Quantitative polarized light microscopy of unstained mammalian cochlear sections

NASA Astrophysics Data System (ADS)

Kalwani, Neil M.; Ong, Cheng Ai; Lysaght, Andrew C.; Haward, Simon J.; McKinley, Gareth H.; Stankovic, Konstantina M.

2013-02-01

Hearing loss is the most common sensory deficit in the world, and most frequently it originates in the inner ear. Yet, the inner ear has been difficult to access for diagnosis because of its small size, delicate nature, complex three-dimensional anatomy, and encasement in the densest bone in the body. Evolving optical methods are promising to afford cellular diagnosis of pathologic changes in the inner ear. To appropriately interpret results from these emerging technologies, it is important to characterize optical properties of cochlear tissues. Here, we focus on that characterization using quantitative polarized light microscopy (qPLM) applied to unstained cochlear sections of the mouse, a common animal model of human hearing loss. We find that the most birefringent cochlear materials are collagen fibrils and myelin. Retardance of the otic capsule, the spiral ligament, and the basilar membrane are substantially higher than that of other cochlear structures. Retardance of the spiral ligament and the basilar membrane decrease from the cochlear base to the apex, compared with the more uniform retardance of other structures. The intricate structural details revealed by qPLM of unstained cochlear sections ex vivo strongly motivate future application of polarization-sensitive optical coherence tomography to human cochlea in vivo.

Quantitative polarized light microscopy of unstained mammalian cochlear sections

PubMed Central

Kalwani, Neil M.; Ong, Cheng Ai; Lysaght, Andrew C.; Haward, Simon J.; McKinley, Gareth H.

2013-01-01

Abstract. Hearing loss is the most common sensory deficit in the world, and most frequently it originates in the inner ear. Yet, the inner ear has been difficult to access for diagnosis because of its small size, delicate nature, complex three-dimensional anatomy, and encasement in the densest bone in the body. Evolving optical methods are promising to afford cellular diagnosis of pathologic changes in the inner ear. To appropriately interpret results from these emerging technologies, it is important to characterize optical properties of cochlear tissues. Here, we focus on that characterization using quantitative polarized light microscopy (qPLM) applied to unstained cochlear sections of the mouse, a common animal model of human hearing loss. We find that the most birefringent cochlear materials are collagen fibrils and myelin. Retardance of the otic capsule, the spiral ligament, and the basilar membrane are substantially higher than that of other cochlear structures. Retardance of the spiral ligament and the basilar membrane decrease from the cochlear base to the apex, compared with the more uniform retardance of other structures. The intricate structural details revealed by qPLM of unstained cochlear sections ex vivo strongly motivate future application of polarization-sensitive optical coherence tomography to human cochlea in vivo. PMID:23407909

Glutamate co-transmission from developing medial nucleus of the trapezoid body - Lateral superior olive synapses is cochlear dependent in kanamycin-treated rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jae Ho; Pradhan, Jonu; Maskey, Dhiraj

Research highlights: {yields} Glutamate co-transmission is enhanced in kanamycin-treated rats. {yields} VGLUT3 expression is increased in kanamycin-treated rats. {yields} GlyR expression is decreased in kanamycin-treated rats. {yields} GlyR, VGLUT3 expression patterns are asymmetric in unilaterally cochlear ablated rat. -- Abstract: Cochlear dependency of glutamate co-transmission at the medial nucleus of the trapezoid body (MNTB) - the lateral superior olive (LSO) synapses was investigated using developing rats treated with high dose kanamycin. Rats were treated with kanamycin from postnatal day (P) 3 to P8. A scanning electron microscopic study on P9 demonstrated partial cochlear hair cell damage. A whole cell voltagemore » clamp experiment demonstrated the increased glutamatergic portion of postsynaptic currents (PSCs) elicited by MNTB stimulation in P9-P11 kanamycin-treated rats. The enhanced VGLUT3 immunoreactivities (IRs) in kanamycin-treated rats and asymmetric VGLUT3 IRs in the LSO of unilaterally cochlear ablated rats supported the electrophysiologic data. Taken together, it is concluded that glutamate co-transmission is cochlear-dependent and enhanced glutamate co-transmission in kanamycin-treated rats is induced by partial cochlear damage.« less

Acute hyperfibrinogenemia impairs cochlear blood flow and hearing function in guinea pigs in vivo.

PubMed

Ihler, Fritz; Strieth, Sebastian; Pieri, Nicos; Göhring, Peter; Canis, Martin

2012-03-01

Impairment of microcirculation is a possible cause of sudden sensorineural hearing loss (SSNHL). Fibrinogen is known as a risk factor for both microvascular dysfunction and SSNHL. Therefore, the aim of this study was to investigate the effect of elevated serum levels of fibrinogen on cochlear blood flow and hearing function in vivo. One group of guinea pigs received two consecutive injections of 100 mg fibrinogen while a control group received equimolar doses of albumin. Measurements of cochlear microcirculation by intravital microscopy and of hearing thresholds by auditory brainstem response (ABR) recordings were carried out before, after first and after second injection. Ten healthy guinea pigs were randomly assigned to a treatment group or a control group of five animals each. Serum fibrinogen levels were elevated after the first and second injections of fibrinogen compared to basal values and control group respectively. Increasing levels of fibrinogen were paralleled by decreasing cochlear blood flow as well as increasing hearing thresholds. Hearing threshold correlated negatively with cochlear blood flow. The effect of microcirculatory impairment on hearing function could be explained by a malfunction of the cochlear amplifier. Further investigation is needed to quantify cochlear potentials under elevated serum fibrinogen levels.

Meningitis following cochlear implantation: pathomechanisms, clinical symptoms, conservative and surgical treatments.

PubMed

Arnold, W; Bredberg, G; Gstöttner, W; Helms, J; Hildmann, H; Kiratzidis, T; Müller, J; Ramsden, R T; Roland, P; Walterspiel, J N

2002-01-01

Pneumococcal otogenic meningitis is a rare postsurgical complication that can develop following stapedectomy or after cochlear implantation. The bacterial infection can be fatal in some instances. A recent increase in the incidence of otogenic meningitis among cochlear implant wearers is of concern. The majority of meningitis cases are associated with a 2-component electrode manufactured by one cochlear implant company. The device with the added 'positioner' component has been withdrawn from the market (FDA Public Health Web Notification: Cochlear Implant Recipients may be at Greater Risk for Meningitis, Updated: August 29, 2002, www.fda.gov/cdrh/safety/cochlear.html). Not all cases have been subsequent to otitis media and symptoms have developed from less than 24 h up to a few years after implantation. The purpose of this paper is to review and discuss the pathogenesis, pathology/bacteriology and to elaborate on some clinical features of otogenic meningitis in implanted children and adults. Essential aspects of surgery, electrode design, and cochleostomy seal are discussed. Conclusions are drawn from the available data and recommendations are made for good practice in cochlear implantation and follow-up. Copyright 2002 S. Karger AG, Basel

The development of the Nucleus Freedom Cochlear implant system.

PubMed

Patrick, James F; Busby, Peter A; Gibson, Peter J

2006-12-01

Cochlear Limited (Cochlear) released the fourth-generation cochlear implant system, Nucleus Freedom, in 2005. Freedom is based on 25 years of experience in cochlear implant research and development and incorporates advances in medicine, implantable materials, electronic technology, and sound coding. This article presents the development of Cochlear's implant systems, with an overview of the first 3 generations, and details of the Freedom system: the CI24RE receiver-stimulator, the Contour Advance electrode, the modular Freedom processor, the available speech coding strategies, the input processing options of Smart Sound to improve the signal before coding as electrical signals, and the programming software. Preliminary results from multicenter studies with the Freedom system are reported, demonstrating better levels of performance compared with the previous systems. The final section presents the most recent implant reliability data, with the early findings at 18 months showing improved reliability of the Freedom implant compared with the earlier Nucleus 3 System. Also reported are some of the findings of Cochlear's collaborative research programs to improve recipient outcomes. Included are studies showing the benefits from bilateral implants, electroacoustic stimulation using an ipsilateral and/or contralateral hearing aid, advanced speech coding, and streamlined speech processor programming.

Use of a gentamicin-impregnated collagen sheet (Collatamp(®)) in the management of major soft tissue complications in pediatric cochlear implants.

PubMed

Benito-González, Fernando; Benito, Jose; Sánchez, Luis Alberto Guardado; Estevez Alonso, Santiago; Muñoz Herrera, Angel; Batuecas-Caletrio, Angel

2014-09-01

The objective was to report the effectiveness of salvage treatment in soft tissue infection around cochlear implants with an absorbable gentamicin collagen sheet and a periosteum and skin rotation flaps. Three patients with cochlear implant and persistent surrounding soft tissue infection are included. All of them underwent antibiotic treatment prior to surgery without any response. In this study preoperative and postoperative audiograms were practiced. Surgical excision of infectious skin and a periosteum and skin rotation flaps were performed. The cochlear implant was refixed in the temporal bone and a gentamicin-impregnated collagen sheet was located covering the cochlear implant. headings In all patients with soft tissue infection around the cochlear implant, infection was completely resolved. It was not necessary to remove the device in any case. The use of an absorbable gentamicin-impregnated collagen sheet is not described for the management of soft tissue complications in pediatric cochlear implant patients. The local application of high concentrations of antibiotic administered by this sheet may be effective against resistant bacteria and, in conjunction with surgery, may resolve this type of complications.

Cochlear Implantation after Bilateral Transverse Temporal Bone Fractures

PubMed Central

Shin, Jong-Heon; Park, SooChan; Baek, Sam-Hyun

2008-01-01

Patients deafened by a severe head injury are rarely encountered. We report a case of a 65-yr-old man with bilateral transverse temporal bone fractures due to head injury. He underwent cochlear implant and achieved a satisfactory auditory rehabilitation. Imaging studies of temporal bone before performing a cochlear implantation provide important information on a patient with bilateral temporal bone fractures. Cochlear implantations with careful planning in such a patient may be a very effective method for aural rehabilitation. PMID:19434252

A preliminary investigation of the air-bone gap: Changes in intracochlear sound pressure with air- and bone-conducted stimuli after cochlear implantation

PubMed Central

Banakis Hartl, Renee M.; Mattingly, Jameson K.; Greene, Nathaniel T.; Jenkins, Herman A.; Cass, Stephen P.; Tollin, Daniel J.

2016-01-01

Hypothesis A cochlear implant electrode within the cochlea contributes to the air-bone gap (ABG) component of postoperative changes in residual hearing after electrode insertion. Background Preservation of residual hearing after cochlear implantation has gained importance as simultaneous electric-acoustic stimulation allows for improved speech outcomes. Postoperative loss of residual hearing has previously been attributed to sensorineural changes; however, presence of increased postoperative air-bone gap remains unexplained and could result in part from altered cochlear mechanics. Here, we sought to investigate changes to these mechanics via intracochlear pressure measurements before and after electrode implantation to quantify the contribution to postoperative air-bone gap. Methods Human cadaveric heads were implanted with titanium fixtures for bone conduction transducers. Velocities of stapes capitulum and cochlear promontory between the two windows were measured using single-axis laser Doppler vibrometry and fiber-optic sensors measured intracochlear pressures in scala vestibuli and tympani for air- and bone-conducted stimuli before and after cochlear implant electrode insertion through the round window. Results Intracochlear pressures revealed only slightly reduced responses to air-conducted stimuli consistent with prior literature. No significant changes were noted to bone-conducted stimuli after implantation. Velocities of the stapes capitulum and the cochlear promontory to both stimuli were stable following electrode placement. Conclusion Presence of a cochlear implant electrode causes alterations in intracochlear sound pressure levels to air, but not bone, conducted stimuli and helps to explain changes in residual hearing noted clinically. These results suggest the possibility of a cochlear conductive component to postoperative changes in hearing sensitivity. PMID:27579835

Recognition and localization of speech by adult cochlear implant recipients wearing a digital hearing aid in the nonimplanted ear (bimodal hearing).

PubMed

Potts, Lisa G; Skinner, Margaret W; Litovsky, Ruth A; Strube, Michael J; Kuk, Francis

2009-06-01

The use of bilateral amplification is now common clinical practice for hearing aid users but not for cochlear implant recipients. In the past, most cochlear implant recipients were implanted in one ear and wore only a monaural cochlear implant processor. There has been recent interest in benefits arising from bilateral stimulation that may be present for cochlear implant recipients. One option for bilateral stimulation is the use of a cochlear implant in one ear and a hearing aid in the opposite nonimplanted ear (bimodal hearing). This study evaluated the effect of wearing a cochlear implant in one ear and a digital hearing aid in the opposite ear on speech recognition and localization. A repeated-measures correlational study was completed. Nineteen adult Cochlear Nucleus 24 implant recipients participated in the study. The participants were fit with a Widex Senso Vita 38 hearing aid to achieve maximum audibility and comfort within their dynamic range. Soundfield thresholds, loudness growth, speech recognition, localization, and subjective questionnaires were obtained six-eight weeks after the hearing aid fitting. Testing was completed in three conditions: hearing aid only, cochlear implant only, and cochlear implant and hearing aid (bimodal). All tests were repeated four weeks after the first test session. Repeated-measures analysis of variance was used to analyze the data. Significant effects were further examined using pairwise comparison of means or in the case of continuous moderators, regression analyses. The speech-recognition and localization tasks were unique, in that a speech stimulus presented from a variety of roaming azimuths (140 degree loudspeaker array) was used. Performance in the bimodal condition was significantly better for speech recognition and localization compared to the cochlear implant-only and hearing aid-only conditions. Performance was also different between these conditions when the location (i.e., side of the loudspeaker array that presented the word) was analyzed. In the bimodal condition, the speech-recognition and localization tasks were equal regardless of which side of the loudspeaker array presented the word, while performance was significantly poorer for the monaural conditions (hearing aid only and cochlear implant only) when the words were presented on the side with no stimulation. Binaural loudness summation of 1-3 dB was seen in soundfield thresholds and loudness growth in the bimodal condition. Measures of the audibility of sound with the hearing aid, including unaided thresholds, soundfield thresholds, and the Speech Intelligibility Index, were significant moderators of speech recognition and localization. Based on the questionnaire responses, participants showed a strong preference for bimodal stimulation. These findings suggest that a well-fit digital hearing aid worn in conjunction with a cochlear implant is beneficial to speech recognition and localization. The dynamic test procedures used in this study illustrate the importance of bilateral hearing for locating, identifying, and switching attention between multiple speakers. It is recommended that unilateral cochlear implant recipients, with measurable unaided hearing thresholds, be fit with a hearing aid.

Relationships among Professionals' Knowledge, Experience, and Expectations Regarding Cochlear Implants

ERIC Educational Resources Information Center

Ben-Itzhak, D.; Most, T.; Weisel, A.

2005-01-01

The present study examined the relationships between teachers' and communication clinicians' self-reported knowledge on cochlear implants and their expectations of CIs. The authors also explored these professionals' views regarding the child's communication mode, educational setting, and social options following cochlear implantation. The…

The Relationship between Cochlear Implants and Deaf Identity

ERIC Educational Resources Information Center

Chapman, Madeline; Dammeyer, Jesper

2017-01-01

The degree to which individuals with cochlear implants (CIs) experience communication difficulties has implications for social participation and identity development. However, few studies have examined the relationship between cochlear implantation, identity, and social participation. Using data from a Danish national survey of deaf adults, the…

Changing patterns of peanut agglutinin labelling in the dorsal cochlear nucleus correspond to axonal ingrowth.

PubMed Central

Riggs, G H; Schweitzer, L

1994-01-01

Various studies have suggested that glycoconjugates may influence connectivity and lamination in the developing central nervous system and may function as barriers to neuritic extension. It has been proposed that the peanut agglutinin lectin labels a glycoconjugate subserving a barrier function. We chose to investigate the distribution of this peanut-agglutinin-labelled glycoconjugate in the dorsal cochlear nucleus of the developing hamster since the development of the dorsal cochlear nucleus is well characterised and its axons obey laminar boundaries. The distribution of peanut agglutinin label throughout the cochlear nucleus delineated zones that cochlear axons fail to invade. In the dorsal cochlear nucleus, laminar differences were reduced on postnatal d 13 and virtually disappearing by postnatal d 23. Label in the molecular layer dissipated as axons and dendrites grew into this layer. These patterns of peanut agglutinin binding correspond to axonal ingrowth and are consistent with a barrier function for glycoconjugates in the molecular layer. Images Fig. 1 Fig. 2 Fig. 4 PMID:7961144

Modulation of Mcl-1 expression reduces age-related cochlear degeneration

PubMed Central

Yang, Wei Ping; Xu, Yang; Guo, Wei Wei; Liu, Hui Zhan; Hu, Bo Hua

2013-01-01

Mcl-1 is an anti-apoptotic member of the Bcl-2 family that modulates apoptosis-related signaling pathways and promotes cell survival. We have previously demonstrated a reduction of Mcl-1 expression in aging cochleae. To investigate whether restoring Mcl-1 expression would reduce aging-related cochlear degeneration, we developed a rat model of Mcl-1 overexpression. A plasmid encoding human Mcl-1/enhanced green fluorescent protein was applied to the round window of the cochlea. This in vivo treatment transfected both the sensory and supporting cells of the cochlear sensory epithelium and enhanced Mcl-1 expression at both the mRNA and the protein level. The upregulation of Mcl-1 expression reduced the progression of age-related cochlear dysfunction and sensory cell death. Furthermore, the transfection of Mcl-1 exerted its protective effect by suppressing cochlear apoptosis at the mitochondrial level. This study demonstrates that the genetic modulation of Mcl-1 expression reduces the progression of age-related cochlear degeneration. PMID:23790646

Gain and frequency tuning within the mouse cochlear apex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oghalai, John S.; Raphael, Patrick D.; Gao, Simon

Normal mammalian hearing requires cochlear outer hair cell active processes that amplify the traveling wave with high gain and sharp tuning, termed cochlear amplification. We have used optical coherence tomography to study cochlear amplification within the apical turn of the mouse cochlea. We measured not only classical basilar membrane vibratory tuning curves but also vibratory responses from the rest of the tissues that compose the organ of Corti. Basilar membrane tuning was sharp in live mice and broad in dead mice, whereas other regions of the organ of Corti demonstrated phase shifts consistent with additional filtering beyond that provided bymore » basilar membrane mechanics. We use these experimental data to support a conceptual framework of how cochlear amplification is tuned within the mouse cochlear apex. We will also study transgenic mice with targeted mutations that affect different biomechanical aspects of the organ of Corti in an effort to localize the underlying processes that produce this additional filtering.« less

Evidence of across-channel processing for spectral-ripple discrimination in cochlear implant listeners.

PubMed

Won, Jong Ho; Jones, Gary L; Drennan, Ward R; Jameyson, Elyse M; Rubinstein, Jay T

2011-10-01

Spectral-ripple discrimination has been used widely for psychoacoustical studies in normal-hearing, hearing-impaired, and cochlear implant listeners. The present study investigated the perceptual mechanism for spectral-ripple discrimination in cochlear implant listeners. The main goal of this study was to determine whether cochlear implant listeners use a local intensity cue or global spectral shape for spectral-ripple discrimination. The effect of electrode separation on spectral-ripple discrimination was also evaluated. Results showed that it is highly unlikely that cochlear implant listeners depend on a local intensity cue for spectral-ripple discrimination. A phenomenological model of spectral-ripple discrimination, as an "ideal observer," showed that a perceptual mechanism based on discrimination of a single intensity difference cannot account for performance of cochlear implant listeners. Spectral modulation depth and electrode separation were found to significantly affect spectral-ripple discrimination. The evidence supports the hypothesis that spectral-ripple discrimination involves integrating information from multiple channels. © 2011 Acoustical Society of America

Evidence of across-channel processing for spectral-ripple discrimination in cochlear implant listeners a

PubMed Central

Ho Won, Jong; Jones, Gary L.; Drennan, Ward R.; Jameyson, Elyse M.; Rubinstein, Jay T.

2011-01-01

Spectral-ripple discrimination has been used widely for psychoacoustical studies in normal-hearing, hearing-impaired, and cochlear implant listeners. The present study investigated the perceptual mechanism for spectral-ripple discrimination in cochlear implant listeners. The main goal of this study was to determine whether cochlear implant listeners use a local intensity cue or global spectral shape for spectral-ripple discrimination. The effect of electrode separation on spectral-ripple discrimination was also evaluated. Results showed that it is highly unlikely that cochlear implant listeners depend on a local intensity cue for spectral-ripple discrimination. A phenomenological model of spectral-ripple discrimination, as an “ideal observer,” showed that a perceptual mechanism based on discrimination of a single intensity difference cannot account for performance of cochlear implant listeners. Spectral modulation depth and electrode separation were found to significantly affect spectral-ripple discrimination. The evidence supports the hypothesis that spectral-ripple discrimination involves integrating information from multiple channels. PMID:21973363

International classification of reliability for implanted cochlear implant receiver stimulators.

PubMed

Battmer, Rolf-Dieter; Backous, Douglas D; Balkany, Thomas J; Briggs, Robert J S; Gantz, Bruce J; van Hasselt, Andrew; Kim, Chong Sun; Kubo, Takeshi; Lenarz, Thomas; Pillsbury, Harold C; O'Donoghue, Gerard M

2010-10-01

To design an international standard to be used when reporting reliability of the implanted components of cochlear implant systems to appropriate governmental authorities, cochlear implant (CI) centers, and for journal editors in evaluating manuscripts involving cochlear implant reliability. The International Consensus Group for Cochlear Implant Reliability Reporting was assembled to unify ongoing efforts in the United States, Europe, Asia, and Australia to create a consistent and comprehensive classification system for the implanted components of CI systems across manufacturers. All members of the consensus group are from tertiary referral cochlear implant centers. None. A clinically relevant classification scheme adapted from principles of ISO standard 5841-2:2000 originally designed for reporting reliability of cardiac pacemakers, pulse generators, or leads. Standard definitions for device failure, survival time, clinical benefit, reduced clinical benefit, and specification were generated. Time intervals for reporting back to implant centers for devices tested to be "out of specification," categorization of explanted devices, the method of cumulative survival reporting, and content of reliability reports to be issued by manufacturers was agreed upon by all members. The methodology for calculating Cumulative survival was adapted from ISO standard 5841-2:2000. The International Consensus Group on Cochlear Implant Device Reliability Reporting recommends compliance to this new standard in reporting reliability of implanted CI components by all manufacturers of CIs and the adoption of this standard as a minimal reporting guideline for editors of journals publishing cochlear implant research results.

Evaluation of Mandarin Chinese Speech Recognition in Adults with Cochlear Implants Using the Spectral Ripple Discrimination Test

PubMed Central

Dai, Chuanfu; Zhao, Zeqi; Zhang, Duo; Lei, Guanxiong

2018-01-01

Background The aim of this study was to explore the value of the spectral ripple discrimination test in speech recognition evaluation among a deaf (post-lingual) Mandarin-speaking population in China following cochlear implantation. Material/Methods The study included 23 Mandarin-speaking adult subjects with normal hearing (normal-hearing group) and 17 deaf adults who were former Mandarin-speakers, with cochlear implants (cochlear implantation group). The normal-hearing subjects were divided into men (n=10) and women (n=13). The spectral ripple discrimination thresholds between the groups were compared. The correlation between spectral ripple discrimination thresholds and Mandarin speech recognition rates in the cochlear implantation group were studied. Results Spectral ripple discrimination thresholds did not correlate with age (r=−0.19; p=0.22), and there was no significant difference in spectral ripple discrimination thresholds between the male and female groups (p=0.654). Spectral ripple discrimination thresholds of deaf adults with cochlear implants were significantly correlated with monosyllabic recognition rates (r=0.84; p=0.000). Conclusions In a Mandarin Chinese speaking population, spectral ripple discrimination thresholds of normal-hearing individuals were unaffected by both gender and age. Spectral ripple discrimination thresholds were correlated with Mandarin monosyllabic recognition rates of Mandarin-speaking in post-lingual deaf adults with cochlear implants. The spectral ripple discrimination test is a promising method for speech recognition evaluation in adults following cochlear implantation in China. PMID:29806954

Evaluation of Mandarin Chinese Speech Recognition in Adults with Cochlear Implants Using the Spectral Ripple Discrimination Test.

PubMed

Dai, Chuanfu; Zhao, Zeqi; Shen, Weidong; Zhang, Duo; Lei, Guanxiong; Qiao, Yuehua; Yang, Shiming

2018-05-28

BACKGROUND The aim of this study was to explore the value of the spectral ripple discrimination test in speech recognition evaluation among a deaf (post-lingual) Mandarin-speaking population in China following cochlear implantation. MATERIAL AND METHODS The study included 23 Mandarin-speaking adult subjects with normal hearing (normal-hearing group) and 17 deaf adults who were former Mandarin-speakers, with cochlear implants (cochlear implantation group). The normal-hearing subjects were divided into men (n=10) and women (n=13). The spectral ripple discrimination thresholds between the groups were compared. The correlation between spectral ripple discrimination thresholds and Mandarin speech recognition rates in the cochlear implantation group were studied. RESULTS Spectral ripple discrimination thresholds did not correlate with age (r=-0.19; p=0.22), and there was no significant difference in spectral ripple discrimination thresholds between the male and female groups (p=0.654). Spectral ripple discrimination thresholds of deaf adults with cochlear implants were significantly correlated with monosyllabic recognition rates (r=0.84; p=0.000). CONCLUSIONS In a Mandarin Chinese speaking population, spectral ripple discrimination thresholds of normal-hearing individuals were unaffected by both gender and age. Spectral ripple discrimination thresholds were correlated with Mandarin monosyllabic recognition rates of Mandarin-speaking in post-lingual deaf adults with cochlear implants. The spectral ripple discrimination test is a promising method for speech recognition evaluation in adults following cochlear implantation in China.

The Modified Rambo Transcanal Approach for Cochlear Implantation in CHARGE Syndrome.

PubMed

Wick, Cameron C; Moore, Amy M; Killeen, Daniel E; Isaacson, Brandon

2017-10-01

CHARGE syndrome is associated with a variety of temporal bone anomalies and deafness. The lack of surgical landmarks and facial nerve irregularities make cochlear implantation in this population a challenging endeavor. This study aims to describe a safe and efficacious transcanal approach for cochlear implantation that obviates the need to perform a mastoidectomy and facial recess. Three children with profound hearing loss secondary to CHARGE syndrome. Transcanal cochlear implantation with closure of the ear canal via a modified Rambo meatoplasty. Retrospective chart review of temporal bone anomalies associated with CHARGE syndrome, technical nuances of this transcanal approach, and cochlear implant outcomes. The mean patient age was 2.5 years (range 1.5-3.8 yr). Two were male and two were left ears. All patients had a hypoplastic mastoid, semicircular canal aplasia, and had some degree of cochlear dysplasia. A full cochlear implant insertion was achieved in all cases, even in the presence of grossly abnormal middle ear and facial nerve anatomy. There were no intraoperative or postoperative complications. The mean follow-up was 12.4 months (range, 3.9-25.2 mo). All three patients use their device daily. Their guardians report improved vocalization and environmental awareness. The modified Rambo transcanal approach provides a safe corridor for cochlear implantation in patients with CHARGE syndrome. This approach minimizes the anatomical variations associated with the syndrome and may reduce the risk of electrode extrusion. Implant outcomes in this patient population remain highly variable based on the patient's global cognitive capacity.

Early Vocabulary Development in Children with Bilateral Cochlear Implants

ERIC Educational Resources Information Center

Välimaa, Taina; Kunnari, Sari; Laukkanen-Nevala, Päivi; Lonka, Eila

2018-01-01

Background: Children with unilateral cochlear implants (CIs) may have delayed vocabulary development for an extended period after implantation. Bilateral cochlear implantation is reported to be associated with improved sound localization and enhanced speech perception in noise. This study proposed that bilateral implantation might also promote…

Deafblind People's Experiences of Cochlear Implantation

ERIC Educational Resources Information Center

Soper, Janet

2006-01-01

Cochlear implants are electronic devices that create the sensation of hearing in those who cannot obtain any benefit from conventional hearing aids. This article examines the experience of cochlear implantation in a select group of individuals with acquired deafblindness, focusing on three key themes: access to communication, information and…

The benefits of remote microphone technology for adults with cochlear implants.

PubMed

Fitzpatrick, Elizabeth M; Séguin, Christiane; Schramm, David R; Armstrong, Shelly; Chénier, Josée

2009-10-01

Cochlear implantation has become a standard practice for adults with severe to profound hearing loss who demonstrate limited benefit from hearing aids. Despite the substantial auditory benefits provided by cochlear implants, many adults experience difficulty understanding speech in noisy environments and in other challenging listening conditions such as television. Remote microphone technology may provide some benefit in these situations; however, little is known about whether these systems are effective in improving speech understanding in difficult acoustic environments for this population. This study was undertaken with adult cochlear implant recipients to assess the potential benefits of remote microphone technology. The objectives were to examine the measurable and perceived benefit of remote microphone devices during television viewing and to assess the benefits of a frequency-modulated system for speech understanding in noise. Fifteen adult unilateral cochlear implant users were fit with remote microphone devices in a clinical environment. The study used a combination of direct measurements and patient perceptions to assess speech understanding with and without remote microphone technology. The direct measures involved a within-subject repeated-measures design. Direct measures of patients' speech understanding during television viewing were collected using their cochlear implant alone and with their implant device coupled to an assistive listening device. Questionnaires were administered to document patients' perceptions of benefits during the television-listening tasks. Speech recognition tests of open-set sentences in noise with and without remote microphone technology were also administered. Participants showed improved speech understanding for television listening when using remote microphone devices coupled to their cochlear implant compared with a cochlear implant alone. This benefit was documented both when listening to news and talk show recordings. Questionnaire results also showed statistically significant differences between listening with a cochlear implant alone and listening with a remote microphone device. Participants judged that remote microphone technology provided them with better comprehension, more confidence, and greater ease of listening. Use of a frequency-modulated system coupled to a cochlear implant also showed significant improvement over a cochlear implant alone for open-set sentence recognition in +10 and +5 dB signal to noise ratios. Benefits were measured during remote microphone use in focused-listening situations in a clinical setting, for both television viewing and speech understanding in noise in the audiometric sound suite. The results suggest that adult cochlear implant users should be counseled regarding the potential for enhanced speech understanding in difficult listening environments through the use of remote microphone technology.

Melodic contour identification by cochlear implant listeners.

PubMed

Galvin, John J; Fu, Qian-Jie; Nogaki, Geraldine

2007-06-01

While the cochlear implant provides many deaf patients with good speech understanding in quiet, music perception and appreciation with the cochlear implant remains a major challenge for most cochlear implant users. The present study investigated whether a closed-set melodic contour identification (MCI) task could be used to quantify cochlear implant users' ability to recognize musical melodies and whether MCI performance could be improved with moderate auditory training. The present study also compared MCI performance with familiar melody identification (FMI) performance, with and without MCI training. For the MCI task, test stimuli were melodic contours composed of 5 notes of equal duration whose frequencies corresponded to musical intervals. The interval between successive notes in each contour was varied between 1 and 5 semitones; the "root note" of the contours was also varied (A3, A4, and A5). Nine distinct musical patterns were generated for each interval and root note condition, resulting in a total of 135 musical contours. The identification of these melodic contours was measured in 11 cochlear implant users. FMI was also evaluated in the same subjects; recognition of 12 familiar melodies was tested with and without rhythm cues. MCI was also trained in 6 subjects, using custom software and melodic contours presented in a different frequency range from that used for testing. Results showed that MCI recognition performance was highly variable among cochlear implant users, ranging from 14% to 91% correct. For most subjects, MCI performance improved as the number of semitones between successive notes was increased; performance was slightly lower for the A3 root note condition. Mean FMI performance was 58% correct when rhythm cues were preserved and 29% correct when rhythm cues were removed. Statistical analyses revealed no significant correlation between MCI performance and FMI performance (with or without rhythmic cues). However, MCI performance was significantly correlated with vowel recognition performance; FMI performance was not correlated with cochlear implant subjects' phoneme recognition performance. Preliminary results also showed that the MCI training improved all subjects' MCI performance; the improved MCI performance also generalized to improved FMI performance. Preliminary data indicate that the closed-set MCI task is a viable approach toward quantifying an important component of cochlear implant users' music perception. The improvement in MCI performance and generalization to FMI performance with training suggests that MCI training may be useful for improving cochlear implant users' music perception and appreciation; such training may be necessary to properly evaluate patient performance, as acute measures may underestimate the amount of musical information transmitted by the cochlear implant device and received by cochlear implant listeners.

[Thalamus and Attention].

PubMed

Tokoro, Kazuhiko; Sato, Hironobu; Yamamoto, Mayumi; Nagai, Yoshiko

2015-12-01

Attention is the process by which information and selection occurs, the thalamus plays an important role in the selective attention of visual and auditory information. Selective attention is a conscious effort; however, it occurs subconsciously, as well. The lateral geniculate body (LGB) filters visual information before it reaches the cortex (bottom-up attention). The thalamic reticular nucleus (TRN) provides a strong inhibitory input to both the LGB and pulvinar. This regulation involves focusing a spotlight on important information, as well as inhibiting unnecessary background information. Behavioral contexts more strongly modulate activity of the TRN and pulvinar influencing feedforward and feedback information transmission between the frontal, temporal, parietal and occipital cortical areas (top-down attention). The medial geniculate body (MGB) filters auditory information the TRN inhibits the MGB. Attentional modulation occurring in the auditory pathway among the cochlea, cochlear nucleus, superior olivary complex, and inferior colliculus is more important than that of the MGB and TRN. We also discuss the attentional consequence of thalamic hemorrhage.

Chip-scale hermetic feedthroughs for implantable bionics.

PubMed

Guenther, Thomas; Dodds, Christopher W D; Lovell, Nigel H; Suaning, Gregg J

2011-01-01

Most implantable medical devices such as cochlear implants and visual prostheses require protection of the stimulating electronics. This is achieved by way of a hermetic feedthrough system which typically features three important attributes: biocompatibility with the human body, device hermeticity and density of feedthrough conductors. On the quest for building a visual neuroprosthesis, a high number of stimulating channels is required. This has encouraged new technologies with higher rates of production yield and further miniaturization. An Al(2)O(3) based feedthrough system has been developed comprising up to 20 platinum feedthroughs per square millimeter. Ceramics substrates are shown to have leak rates below 1 × 10(-12) atm × cc/s, thus exceeding the resolution limits of most commercially available leak detectors. A sheet resistance of 0.05 Ω can be achieved. This paper describes the design, fabrication process and hermeticity testing of high density feedthroughs for use in neuroprosthetic implants.

Lexical-Access Ability and Cognitive Predictors of Speech Recognition in Noise in Adult Cochlear Implant Users

PubMed Central

Smits, Cas; Merkus, Paul; Festen, Joost M.; Goverts, S. Theo

2017-01-01

Not all of the variance in speech-recognition performance of cochlear implant (CI) users can be explained by biographic and auditory factors. In normal-hearing listeners, linguistic and cognitive factors determine most of speech-in-noise performance. The current study explored specifically the influence of visually measured lexical-access ability compared with other cognitive factors on speech recognition of 24 postlingually deafened CI users. Speech-recognition performance was measured with monosyllables in quiet (consonant-vowel-consonant [CVC]), sentences-in-noise (SIN), and digit-triplets in noise (DIN). In addition to a composite variable of lexical-access ability (LA), measured with a lexical-decision test (LDT) and word-naming task, vocabulary size, working-memory capacity (Reading Span test [RSpan]), and a visual analogue of the SIN test (text reception threshold test) were measured. The DIN test was used to correct for auditory factors in SIN thresholds by taking the difference between SIN and DIN: SRTdiff. Correlation analyses revealed that duration of hearing loss (dHL) was related to SIN thresholds. Better working-memory capacity was related to SIN and SRTdiff scores. LDT reaction time was positively correlated with SRTdiff scores. No significant relationships were found for CVC or DIN scores with the predictor variables. Regression analyses showed that together with dHL, RSpan explained 55% of the variance in SIN thresholds. When controlling for auditory performance, LA, LDT, and RSpan separately explained, together with dHL, respectively 37%, 36%, and 46% of the variance in SRTdiff outcome. The results suggest that poor verbal working-memory capacity and to a lesser extent poor lexical-access ability limit speech-recognition ability in listeners with a CI. PMID:29205095

Negotiating Reassurance: Parents' Narratives on Follow-Up after Cochlear Implantation

ERIC Educational Resources Information Center

Bruin, Marieke; Ohna, Stein Erik

2015-01-01

This study presents an analysis of parental experiences on follow-up after cochlear implantation. Data were constructed in semi-structured, individual interviews with the parents of 14 children who use cochlear implants. Drawing on narrative analysis, the study explores parental responses to insecurity concerning children's learning and…

Concept Learning and Heuristic Classification in Weak-Theory Domains

DTIC Science & Technology

1990-03-01

age and noise-induced cochlear age..gt.60 noise-induced cochlear air(mild) age-induced cochlear history(noise) norma ]_ear speechpoor)acousticneuroma...Annual review of computer science. Machine Learning, 4, 1990. (to appear). [18] R.T. Duran . Concept learning with incomplete data sets. Master’s thesis

Challenges in Optimizing Oral Communication in Children with Cochlear Implants.

ERIC Educational Resources Information Center

Ertmer, David J.

2002-01-01

This article introduces a forum that provides information for assisting speech-language pathologists and audiologists in fulfilling their professional responsibilities in a variety of settings to children with hearing impairments who have cochlear implants. A preview of the following articles on services for children with cochlear implants is…

Agile Development of Advanced Prototypes

DTIC Science & Technology

2014-11-01

prostheses: retinal implants, cochlear implants, and neuroprosthetics (EEG controlled artificial limbs); an interactive, virtual experience...demonstrations allowing users to experience, from a patient’s perspective life with three different prostheses: retinal implants, cochlear implants...three experiences were researched and developed. The applications are interactive demonstrations of retinal implants, cochlear implants, and

Voice emotion perception and production in cochlear implant users.

PubMed

Jiam, N T; Caldwell, M; Deroche, M L; Chatterjee, M; Limb, C J

2017-09-01

Voice emotion is a fundamental component of human social interaction and social development. Unfortunately, cochlear implant users are often forced to interface with highly degraded prosodic cues as a result of device constraints in extraction, processing, and transmission. As such, individuals with cochlear implants frequently demonstrate significant difficulty in recognizing voice emotions in comparison to their normal hearing counterparts. Cochlear implant-mediated perception and production of voice emotion is an important but relatively understudied area of research. However, a rich understanding of the voice emotion auditory processing offers opportunities to improve upon CI biomedical design and to develop training programs benefiting CI performance. In this review, we will address the issues, current literature, and future directions for improved voice emotion processing in cochlear implant users. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluating cochlear implant trauma to the scala vestibuli.

PubMed

Adunka, O; Kiefer, J; Unkelbach, M H; Radeloff, A; Gstoettner, W

2005-04-01

Placement of cochlear implant electrodes into the scala vestibuli may be intentional, e.g. in case of blocked scala tympani or unintentional as a result of trauma to the basilar membrane or erroneous location of the cochieostomy. The aim of this study was to evaluate the morphological consequences and cochlear trauma after implantation of different cochlear implant electrode arrays in the scala vestibuli. Human temporal bone study with histological and radiological evaluation. Twelve human cadaver temporal bones were implanted with different cochlear implant electrodes. Implanted bones were processed using a special method to section undecalcified bone. Cochlear trauma and intracochlear positions. All implanted electrodes were implanted into the scala vestibuli using a special approach that allows direct scala vestibuli insertions. Fractures of the osseous spiral lamina were evaluated in some bones in the basal cochlear regions. In most electrodes, delicate structures of the organ of Corti were left intact, however, Reissner's membrane was destroyed in all specimens and the electrode lay upon the tectorial membrane. In some bones the organ of Corti was destroyed. Scala vestibuli insertions did not cause severe trauma to osseous or neural structures, thus preserving the basis for electrostimulation of the cochlea. However, destruction of Reissner's membrane and impact on the Organ of Corti can be assumed to destroy residual hearing.

Cochlear implantation for single-sided deafness and tinnitus suppression.

PubMed

Holder, Jourdan T; O'Connell, Brendan; Hedley-Williams, Andrea; Wanna, George

To quantify the potential effectiveness of cochlear implantation for tinnitus suppression in patients with single-sided deafness using the Tinnitus Handicap Inventory. The study included 12 patients with unilateral tinnitus who were undergoing cochlear implantation for single-sided deafness. The Tinnitus Handicap Inventory was administered at the patient's cochlear implant candidacy evaluation appointment prior to implantation and every cochlear implant follow-up appointment, except activation, following implantation. Patient demographics and speech recognition scores were also retrospectively recorded using the electronic medical record. A significant reduction was found when comparing Tinnitus Handicap Inventory score preoperatively (61.2±27.5) to the Tinnitus Handicap Inventory score after three months of cochlear implant use (24.6±28.2, p=0.004) and the Tinnitus Handicap Inventory score beyond 6months of CI use (13.3±18.9, p=0.008). Further, 45% of patients reported total tinnitus suppression. Mean CNC word recognition score improved from 2.9% (SD 9.4) pre-operatively to 40.8% (SD 31.7) by 6months post-activation, which was significantly improved from pre-operative scores (p=0.008). The present data is in agreement with previously published studies that have shown an improvement in tinnitus following cochlear implantation for the large majority of patients with single-sided deafness. Copyright © 2017 Elsevier Inc. All rights reserved.

Piribedil affects dopamine turnover in cochleas stimulated by white noise.

PubMed

Gil-Loyzaga, P; Vicente-Torres, M A; Fernández-Mateos, P; Arce, A; Esquifino, A

1994-09-01

The presence of dopamine (DA) within the cochlea has been previously reported, indicating that its turnover increases under noise stimulation. In the present report, piribedil, a dopaminergic D2 agonist, was used in order to provide evidence of the activity of D2 receptors in the turnover of DA under noise stimulation. Long-Evans rats were intraperitoneally injected with distilled water or with a solution of piribedil one hour previously to either noise or silence exposure. Noise stimulation was performed in an anechoic chamber at 70, 90 or 110 dB SPL for one hour. The animals were then sacrificed and the cochlear contents of DA and its metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were quantified by HPLC with electrochemical detection. The administration of piribedil to animals kept in silence did not modify the cochlear DA, DOPAC and HVA content. Noise stimulation resulted in a decrease of the cochlear DA content and an increase of the cochlear DOPAC and HVA contents in vehicle treated animals. The administration of piribedil resulted in a blockade of this noise induced cochlear DA turnover. These results suggest that piribedil stimulates cochlear D2 receptors controlling the cochlear DA release. Piribedil action on D2 receptors could explain the improvement observed in some cochleo-vestibular diseases signs after piribedil treatment.

Considerations for Pediatric Cochlear Implant Recipients With Unilateral or Asymmetric Hearing Loss: Assessment, Device Fitting, and Habilitation.

PubMed

Greaver, Laura; Eskridge, Hannah; Teagle, Holly F B

2017-06-13

The purpose of this clinical report is to present case studies of children who are nontraditional candidates for cochlear implantation because they have significant residual hearing in 1 ear and to describe outcomes and considerations for their audiological management and habilitation. Case information is presented for 5 children with profound hearing loss in 1 ear and normal or mild-to-moderate hearing loss in the opposite ear and who have undergone unilateral cochlear implantation. Pre- and postoperative assessments were performed per typical clinic routines with modifications described. Postimplant habilitation was customized for each recipient using a combination of traditional methods, newer technologies, and commercial materials. The 5 children included in this report are consistent users of their cochlear implants and demonstrate speech recognition in the implanted ear when isolated from the better hearing ear. Candidacy criteria for cochlear implantation are evolving. Children with single-sided deafness or asymmetric hearing loss who have traditionally not been considered candidates for cochlear implantation should be evaluated on a case-by-case basis. Audiological management of these recipients is not vastly different compared with children who are traditional cochlear implant recipients. Assessment and habilitation techniques must be modified to isolate the implanted ear to obtain accurate results and to provide meaningful therapeutic intervention.

Spatiotemporal expression of Ezh2 in the developing mouse cochlear sensory epithelium.

PubMed

Chen, Yan; Li, Wenyan; Li, Wen; Chai, Renjie; Li, Huawei

2016-09-01

The enhancer of zeste 2 polycomb repressive complex 2 subunit (Ezh2) is a histone-lysine Nmethyltransferase enzyme that participates in DNA methylation. Ezh2 has also been reported to play crucial roles in stem cell proliferation and differentiation. However, the detailed expression profile of Ezh2 during mouse cochlear development has not been investigated. Here, we examined the spatiotemporal expression of Ezh2 in the cochlea during embryonic and postnatal development. Ezh2 expression began to be observed in the whole otocyst nuclei at embryonic day 9.5 (E9.5). At E12.5, Ezh2 was expressed in the nuclei of the cochlear prosensory epithelium. At E13.5 and E15.5, Ezh2 was expressed from the apical to the basal turns in the nuclei of the differentiating cochlear epithelium. At postnatal day (P) 0 and 7, the Ezh2 expression was located in the nuclei of the cochlear epithelium in all three turns and could be clearly seen in outer and inner hair cells, supporting cells, the stria vascularis, and spiral ganglion cells. Ezh2 continued to be expressed in the cochlear epithelium of adult mice. Our results provide the basic Ezh2 expression pattern and might be useful for further investigating the detailed role of Ezh2 during cochlear development.

Predicting the location of missing outer hair cells using the electrical signal recorded at the round window

PubMed Central

Chertoff, Mark E.; Earl, Brian R.; Diaz, Francisco J.; Sorensen, Janna L.; Thomas, Megan L. A.; Kamerer, Aryn M.; Peppi, Marcello

2014-01-01

The electrical signal recorded at the round window was used to estimate the location of missing outer hair cells. The cochlear response was recorded to a low frequency tone embedded in high-pass filtered noise conditions. Cochlear damage was created by either overexposure to frequency-specific tones or laser light. In animals with continuous damage along the partition, the amplitude of the cochlear response increased as the high-pass cutoff frequency increased, eventually reaching a plateau. The cochlear distance at the onset of the plateau correlated with the anatomical onset of outer hair cell loss. A mathematical model replicated the physiologic data but was limited to cases with continuous hair cell loss in the middle and basal turns. The neural contribution to the cochlear response was determined by recording the response before and after application of Ouabain. Application of Ouabain eliminated or reduced auditory neural activity from approximately two turns of the cochlea. The amplitude of the cochlear response was reduced for moderate signal levels with a limited effect at higher levels, indicating that the cochlear response was dominated by outer hair cell currents at high signal levels and neural potentials at low to moderate signal levels. PMID:25190395

[Audiophonological evaluation of 16 children fitted with cochlear implants for sensorineural hearing loss induced by bacterial meningitis].

PubMed

Teissier, N; Doehring, I; Noel-Petroff, N; Elmaleh-Bergès, M; Viala, P; François, M; Faye, A; Van Den Abbeele, T; Lorrot, M

2013-06-01

Bacterial meningitis (BM) is the primary etiology of acquired sensorineural hearing loss (SNHL) in children and may compromise language development. Since the 1990 s, cochlear implants (CIs) have become part of the management of children with profound SNHL with encouraging results. The aim of this study was to analyze the audiophonological performance of children before and after cochlear implantation for SNHL following bacterial meningitis. Retrospective study of all children fitted with CIs for bilateral severe to profound SNHL after bacterial meningitis in the Robert-Debré pediatric ENT department between August 1990 and March 2009. Audiophonological performance was assessed using the APCEI profile. Of the 283 children receiving implants during that period, 16 children (6%; 6 boys, 10 girls) underwent CI implantation after bacterial meningitis (Streptococcus pneumoniae in 8 cases, Neisseria meningitidis in 2 cases, and Haemophilus influenzae in 4 cases). The mean time from meningitis to SNHL was 8.3 months (median, 1.5 months; range, 1 day to 13 years). The mean time from meningitis to cochlear implantation was 2 years and 3 months (median, 7 months; range, 1 month to 13 years 3 months). Twelve children (75%) presented partial cochlear and/or vestibular ossification on presurgical CT scan. Three children received bilateral implants. Thirteen children (81%) developed early SNHL in the first 3 months, whereas 3 children developed SNHL more than 10 months after meningitis. As for the benefits of cochlear implantation, 11 children presented near to normal intelligibility and optimal use of their cochlear implant; 5 children presented partial benefits due to neurological sequelae (1), a long delay before implantation (1), technical problems (2), or a social problem in relation to low socioeconomic status (1). After bacterial meningitis, audiological evaluation must be made carefully during the first 3 months to detect early SNHL, but SNHL may also develop several years later. In case of profound SNHL and a modified signal of the labyrinth on the MRI, cochlear implantation must be performed without delay before cochlear and/or vestibular ossification. Cochlear implantation is an effective technique with good long-term audiologic results. The coexistence of neurological lesions may compromise the results, but it should not contraindicate a cochlear implantation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Modeling open-set spoken word recognition in postlingually deafened adults after cochlear implantation: some preliminary results with the neighborhood activation model.

PubMed

Meyer, Ted A; Frisch, Stefan A; Pisoni, David B; Miyamoto, Richard T; Svirsky, Mario A

2003-07-01

Do cochlear implants provide enough information to allow adult cochlear implant users to understand words in ways that are similar to listeners with acoustic hearing? Can we use a computational model to gain insight into the underlying mechanisms used by cochlear implant users to recognize spoken words? The Neighborhood Activation Model has been shown to be a reasonable model of word recognition for listeners with normal hearing. The Neighborhood Activation Model assumes that words are recognized in relation to other similar-sounding words in a listener's lexicon. The probability of correctly identifying a word is based on the phoneme perception probabilities from a listener's closed-set consonant and vowel confusion matrices modified by the relative frequency of occurrence of the target word compared with similar-sounding words (neighbors). Common words with few similar-sounding neighbors are more likely to be selected as responses than less common words with many similar-sounding neighbors. Recent studies have shown that several of the assumptions of the Neighborhood Activation Model also hold true for cochlear implant users. Closed-set consonant and vowel confusion matrices were obtained from 26 postlingually deafened adults who use cochlear implants. Confusion matrices were used to represent input errors to the Neighborhood Activation Model. Responses to the different stimuli were then generated by the Neighborhood Activation Model after incorporating the frequency of occurrence counts of the stimuli and their neighbors. Model outputs were compared with obtained performance measures on the Consonant-Vowel Nucleus-Consonant word test. Information transmission analysis was used to assess whether the Neighborhood Activation Model was able to successfully generate and predict word and individual phoneme recognition by cochlear implant users. The Neighborhood Activation Model predicted Consonant-Vowel Nucleus-Consonant test words at levels similar to those correctly identified by the cochlear implant users. The Neighborhood Activation Model also predicted phoneme feature information well. The results obtained suggest that the Neighborhood Activation Model provides a reasonable explanation of word recognition by postlingually deafened adults after cochlear implantation. It appears that multichannel cochlear implants give cochlear implant users access to their mental lexicons in a manner that is similar to listeners with acoustic hearing. The lexical properties of the test stimuli used to assess performance are important to spoken-word recognition and should be included in further models of the word recognition process.

Recognition and Localization of Speech by Adult Cochlear Implant Recipients Wearing a Digital Hearing Aid in the Nonimplanted Ear (Bimodal Hearing)

PubMed Central

Potts, Lisa G.; Skinner, Margaret W.; Litovsky, Ruth A.; Strube, Michael J; Kuk, Francis

2010-01-01

Background The use of bilateral amplification is now common clinical practice for hearing aid users but not for cochlear implant recipients. In the past, most cochlear implant recipients were implanted in one ear and wore only a monaural cochlear implant processor. There has been recent interest in benefits arising from bilateral stimulation that may be present for cochlear implant recipients. One option for bilateral stimulation is the use of a cochlear implant in one ear and a hearing aid in the opposite nonimplanted ear (bimodal hearing). Purpose This study evaluated the effect of wearing a cochlear implant in one ear and a digital hearing aid in the opposite ear on speech recognition and localization. Research Design A repeated-measures correlational study was completed. Study Sample Nineteen adult Cochlear Nucleus 24 implant recipients participated in the study. Intervention The participants were fit with a Widex Senso Vita 38 hearing aid to achieve maximum audibility and comfort within their dynamic range. Data Collection and Analysis Soundfield thresholds, loudness growth, speech recognition, localization, and subjective questionnaires were obtained six–eight weeks after the hearing aid fitting. Testing was completed in three conditions: hearing aid only, cochlear implant only, and cochlear implant and hearing aid (bimodal). All tests were repeated four weeks after the first test session. Repeated-measures analysis of variance was used to analyze the data. Significant effects were further examined using pairwise comparison of means or in the case of continuous moderators, regression analyses. The speech-recognition and localization tasks were unique, in that a speech stimulus presented from a variety of roaming azimuths (140 degree loudspeaker array) was used. Results Performance in the bimodal condition was significantly better for speech recognition and localization compared to the cochlear implant–only and hearing aid–only conditions. Performance was also different between these conditions when the location (i.e., side of the loudspeaker array that presented the word) was analyzed. In the bimodal condition, the speech-recognition and localization tasks were equal regardless of which side of the loudspeaker array presented the word, while performance was significantly poorer for the monaural conditions (hearing aid only and cochlear implant only) when the words were presented on the side with no stimulation. Binaural loudness summation of 1–3 dB was seen in soundfield thresholds and loudness growth in the bimodal condition. Measures of the audibility of sound with the hearing aid, including unaided thresholds, soundfield thresholds, and the Speech Intelligibility Index, were significant moderators of speech recognition and localization. Based on the questionnaire responses, participants showed a strong preference for bimodal stimulation. Conclusions These findings suggest that a well-fit digital hearing aid worn in conjunction with a cochlear implant is beneficial to speech recognition and localization. The dynamic test procedures used in this study illustrate the importance of bilateral hearing for locating, identifying, and switching attention between multiple speakers. It is recommended that unilateral cochlear implant recipients, with measurable unaided hearing thresholds, be fit with a hearing aid. PMID:19594084

Intraoperative cochlear nerve mapping with the mobile cochlear nerve compound action potential tracer in vestibular schwannoma surgery.

PubMed

Watanabe, Nobuyuki; Ishii, Takuya; Fujitsu, Kazuhiko; Kaku, Shogo; Ichikawa, Teruo; Miyahara, Kosuke; Okada, Tomu; Tanino, Shin; Uriu, Yasuhiro; Murayama, Yuichi

2018-05-18

OBJECTIVE The authors describe the usefulness and limitations of the cochlear nerve compound action potential (CNAP) mobile tracer (MCT) that they developed to aid in cochlear nerve mapping during vestibular schwannoma surgery (VSS) for hearing preservation. METHODS This MCT device requires no more than 2 seconds for stable placement on the nerve to obtain the CNAP and thus is able to trace the cochlear nerve instantaneously. Simultaneous bipolar and monopolar recording is possible. The authors present the outcomes of 18 consecutive patients who underwent preoperative useful hearing (defined as class I or II of the Gardner-Robertson classification system) and underwent hearing-preservation VSS with the use of the MCT. Mapping was considered successful when it was possible to detect and trace the cochlear nerve. RESULTS Mapping of the cochlear nerve was successful in 13 of 18 patients (72.2%), and useful hearing was preserved in 11 patients (61.1%). Among 8 patients with large tumors (Koos grade 3 or 4), the rate of successful mapping was 62.5% (5 patients). The rate of hearing preservation in patients with large tumors was 50% (4 patients). CONCLUSIONS In addition to microsurgical presumption of the arrangement of each nerve, frequent probing on and around an unidentified nerve and comparison of each waveform are advisable with the use of both more sensitive monopolar and more location-specific bipolar MCT. MCT proved to be useful in cochlear nerve mapping and may consequently be helpful in hearing preservation. The authors discuss some limitations and problems with this device.

Timing Discrepancies of Early Intervention Hearing Services in Urban and Rural Cochlear Implant Recipients

PubMed Central

Bush, Matthew L.; Burton, Mary; Loan, Ashley; Shinn, Jennifer B.

2013-01-01

Objective The purpose of this study was to examine the timing of early intervention diagnostic and therapeutic services in cochlear implant recipients from rural and urban areas. Study design Retrospective case series review Setting Tertiary referral center Patients Cochlear implant recipients from a single comprehensive hearing institute born with severe congenital sensorineural hearing loss were examined. Timing of diagnostic and therapeutic services was examined. Intervention(s) Diagnosis, amplification, and eventual cochlear implantation for all patients in the study Main outcome measure(s) Time points of definitive diagnosis, amplification, and cochlear implantation for children from urban and rural regions were examined. Correlation analysis of distance to testing center and timing of services was also assessed. Results 40 children born with congenital hearing loss were included in the study and were diagnosed at a median age of 13 weeks after birth. Children from rural regions obtained amplification at a median age of 47.7 weeks after birth, while urban children were amplified at 26 weeks after birth. Cochlear implantation was performed at a median age of 182 weeks after birth in those from rural areas and at 104 weeks after birth in urban-dwelling patients. A linear relationship was identified between distance to the implant center and timing of hearing aid amplification (r=0.5, p=0.033) and cochlear implantation (r=0.5, p=0.016). Conclusions Children residing outside of metro areas may be at higher risk of delayed rehabilitative services and cochlear implantation than those residing in urban areas that may be closer in proximity to tertiary care centers. PMID:24136305

The cochlear CRF signaling systems and their mechanisms of action in modulating cochlear sensitivity and protection against trauma

PubMed Central

Graham, Christine E.; Basappa, Johnvesly; Turcan, Sevin; Vetter, Douglas E.

2011-01-01

A key requirement for encoding the auditory environment is the ability to dynamically alter cochlear sensitivity. However, merely attaining a steady state of maximal sensitivity is not a viable solution since the sensory cells and ganglion cells of the cochlea are prone to damage following exposure to loud sound. Most often, such damage is via initial metabolic insult that can lead to cellular death. Thus, establishing the highest sensitivity must be balanced with protection against cellular metabolic damage that can lead to loss of hair cells and ganglion cells, resulting in loss of frequency representation. While feedback mechanisms are known to exist in the cochlea that alter sensitivity, they respond only after stimulus encoding, allowing potentially damaging sounds to impact the inner ear at times coincident with increased sensitivity. Thus, questions remain concerning the endogenous signaling systems involved in dynamic modulation of cochlear sensitivity and protection against metabolic stress. Understanding endogenous signaling systems involved in cochlear protection may lead to new strategies and therapies for prevention of cochlear damage and consequent hearing loss. We have recently discovered a novel cochlear signaling system that is molecularly equivalent to the classic hypothalamic-pituitary-adrenal (HPA) axis. This cochlear HPA-equivalent system functions to balance auditory sensitivity and susceptibility to noise-induced hearing loss, and also protects against cellular metabolic insults resulting from exposures to ototoxic drugs. We review the anatomy, physiology, and cellular signaling of this system, and compare it to similar signaling in other organs/tissues of the body. PMID:21909974

Preventing hearing damage using topical dexamethasone during reversible cochlear ischemia: an animal model.

PubMed

Morawski, Krzysztof; Telischi, Fred F; Bohorquez, Jorge; Niemczyk, Kazimierz

2009-09-01

Local application of dexamethasone to the round window (RW) niche prevents cochlear damage caused by local reversible ischemia. Cochlear ischemia induced by internal auditory artery (IAA) compression/stretching is thought to cause postoperative sensory hearing loss after attempted hearing preservation removal of acoustic neuroma tumors. Dexamethasone administered to the RW niche traveling through the membrane to the cochlear fluids may prevent ischemic damage. Ten young albino rabbits were used for this study. Ischemic episodes were induced by compressing the IAA. Laser Doppler cochlear blood flow was measured using a probe positioned at the RW niche. Transtympanic electrocochleography was measured at 4, 8, and 12 kHz. In 5 test ears, dexamethasone was administered topically at the RW for approximately 50 minutes before the IAA compressions, whereas in 5 control ears, saline was applied in the same way. Each ear underwent one 10-minute IAA compression with a 60-minute postischemic period of transtympanic electrocochleography monitoring. In both control- and dexamethasone-treated ears, ischemic episodes measured by Laser Doppler cochlear blood flow were comparable. Fifty minutes after IAA decompression, in dexamethasone-pretreated ears, cochlear microphonic and compound action potential amplitudes at all test frequencies were 10 to 15% less reduced than those in control ears. Compound action potential latencies in dexamethasone-pretreated ears resulted in shorter latency delay than in control ears. The RW seems to be an efficacious route for the administration of dexamethasone into the inner ear. Dexamethasone showed a protective effect on cochlear function after local ischemia. Transtympanic electrocochleography was found to be a sufficient and effective tool in monitoring hearing.

Quality-of-life benefit from cochlear implantation in the elderly.

PubMed

Vermeire, Katrien; Brokx, Jan P L; Wuyts, Floris L; Cochet, Ellen; Hofkens, Anouk; Van de Heyning, Paul H

2005-03-01

To compare the audiologic results of geriatric patients receiving cochlear implants with younger age groups and to evaluate the quality of life after cochlear implantation in the geriatric population by means of validated quality-of-life questionnaires. Cross-sectional study involving 89 postlingually deafened cochlear implant subjects. Tertiary referral center. A total of 89 postlingually deafened patients were included in the study, among which were 25 patients who were aged 70 years or older. All patients received a cochlear implant. Subjects were implanted with either the Laura, Nucleus 24, or Med-el Combi 40+ cochlear implant systems implementing the SPEAK, ACE, CIS, or CIS+ coding strategies. Speech recognition was determined by means of phonetically balanced monosyllabic word lists. The Hearing Handicap Inventory for Adults, the Glasgow Benefit Inventory, and the scale for the prediction of hearing disability in sensorineural hearing loss were used to quantify the quality of life. Mean audiologic performance for the three groups increased significantly after implantation (p < 0.001). Postoperative audiologic performance of the geriatric population led to useful hearing, but these scores were significantly lower than for the younger age groups (p = 0.002). However, the quality-of-life outcomes for the geriatric group were similar to those of the younger age groups (p = 0.411 for the Hearing Handicap Inventory for Adults; p = 0.886 for the Glasgow Benefit Inventory). The results of this study prove that cochlear implantation in the elderly provides improvements in quality of life and speech understanding, similar to those for younger adult cochlear implant recipients.

EEG frontal asymmetry related to pleasantness of music perception in healthy children and cochlear implanted users.

PubMed

Vecchiato, G; Maglione, A G; Scorpecci, A; Malerba, P; Marsella, P; Di Francesco, G; Vitiello, S; Colosimo, A; Babiloni, Fabio

2012-01-01

Interestingly, the international debate about the quality of music fruition for cochlear implanted users does not take into account the hypothesis that bilateral users could perceive music in a more pleasant way with respect to monolateral users. In this scenario, the aim of the present study was to investigate if cerebral signs of pleasantness during music perception in healthy child are similar to those observed in monolateral and in bilateral cochlear implanted users. In fact, previous observations in literature on healthy subjects have indicated that variations of the frontal EEG alpha activity are correlated with the perceived pleasantness of the sensory stimulation received (approach-withdrawal theory). In particular, here we described differences between cortical activities estimated in the alpha frequency band for a healthy child and in patients having a monolateral or a bilateral cochlear implant during the fruition of a musical cartoon. The results of the present analysis showed that the alpha EEG asymmetry patterns observed in a healthy child and that of a bilateral cochlear implanted patient are congruent with the approach-withdrawal theory. Conversely, the scalp topographic distribution of EEG power spectra in the alpha band resulting from the monolateral cochlear user presents a different EEG pattern from the normal and bilateral implanted patients. Such differences could be explained at the light of the approach-withdrawal theory. In fact, the present findings support the hypothesis that a monolateral cochlear implanted user could perceive the music in a less pleasant way when compared to a healthy subject or to a bilateral cochlear user.

Educational, employment, and social participation of young adult graduates from the paediatric Southern Cochlear Implant Programme, New Zealand.

PubMed

Goh, Terence; Bird, Philip; Pearson, John; Mustard, Jill

2016-01-01

The purpose of this study is to observe the education and vocational achievements and social participation of cochlear implant recipients as they graduate from a paediatric cochlear implant programme and identify any significant associations that might exist. This study identified 56 patients from the Southern Cochlear Implant Programme (SCIP) who received cochlear implants before the age of 19 (paediatric) and are now over the age of 19 (adult). A questionnaire investigated their education, employment, and identity with the hearing and deaf communities. Also included were the satisfaction with life scale and Hearing Participation Scale (HPS). Subjects ranged in age from 19 to 32. Twenty-six patients responded to the questionnaire, including one non-user. Twenty identified strongly or very strongly with the hearing community. There was weak evidence of a linear association between strong identity with the hearing community and a higher HPS score. No other statistically significant associations were detected. Interestingly, 12 out of 26 participants found employment through family. Positive outcome trends in education and employment were seen in this study although no statistical significance was achieved. There is a strong bias for those who use their cochlear implants regularly, and there are no data available for those who do not use their cochlear implants for comparison as only one non-user completed the survey, despite efforts to include this group. This study shows that there is perceived benefit in implantation for patients who use it regularly but further research is needed with a more diverse group of cochlear implant recipients.

Audiovisual integration in children listening to spectrally degraded speech.

PubMed

Maidment, David W; Kang, Hi Jee; Stewart, Hannah J; Amitay, Sygal

2015-02-01

The study explored whether visual information improves speech identification in typically developing children with normal hearing when the auditory signal is spectrally degraded. Children (n=69) and adults (n=15) were presented with noise-vocoded sentences from the Children's Co-ordinate Response Measure (Rosen, 2011) in auditory-only or audiovisual conditions. The number of bands was adaptively varied to modulate the degradation of the auditory signal, with the number of bands required for approximately 79% correct identification calculated as the threshold. The youngest children (4- to 5-year-olds) did not benefit from accompanying visual information, in comparison to 6- to 11-year-old children and adults. Audiovisual gain also increased with age in the child sample. The current data suggest that children younger than 6 years of age do not fully utilize visual speech cues to enhance speech perception when the auditory signal is degraded. This evidence not only has implications for understanding the development of speech perception skills in children with normal hearing but may also inform the development of new treatment and intervention strategies that aim to remediate speech perception difficulties in pediatric cochlear implant users.

Pediatric Cochlear Implants: An Overview of the Alternatives in Education and Rehabilitation.

ERIC Educational Resources Information Center

Barnes, Judith M., Ed.; And Others

This collection of 10 papers is intended as a resource book integrating information on pediatric cochlear implants for educators, parents, implant teams, and rehabilitation specialists. The papers focus on the importance of providing an oral educational environment to maximize cochlear implant success. An introduction notes controversies in the…

Realization of Complex Onsets by Pediatric Users of Cochlear Implants

ERIC Educational Resources Information Center

Chin, Steven B.

2006-01-01

This study examined variations in English complex onset realizations by children who use cochlear implants. Data consisted of 227 productions of two-segment onset clusters from 12 children. In general, onset cluster realizations of children with cochlear implants did not differ markedly from those reported for children with normal hearing: null…

Contribution of Family Environment to Pediatric Cochlear Implant Users' Speech and Language Outcomes: Some Preliminary Findings

ERIC Educational Resources Information Center

Holt, Rachael Frush; Beer, Jessica; Kronenberger, William G.; Pisoni, David B.; Lalonde, Kaylah

2012-01-01

Purpose: To evaluate the family environments of children with cochlear implants and to examine relationships between family environment and postimplant language development and executive function. Method: Forty-five families of children with cochlear implants completed a self-report family environment questionnaire (Family Environment Scale-Fourth…

Taxonomic Knowledge of Children with and without Cochlear Implants

ERIC Educational Resources Information Center

Lund, Emily; Dinsmoor, Jessica

2016-01-01

Purpose: The purpose of this study was to compare the taxonomic vocabulary knowledge and organization of children with cochlear implants to (a) children with normal hearing matched for age, and (b) children matched for vocabulary development. Method: Ten children with cochlear implants, 10 age-matched children with normal hearing, and 10…

Children with Cochlear Implants in Australia: Educational Settings, Supports, and Outcomes

ERIC Educational Resources Information Center

Punch, Renee; Hyde, Merv

2010-01-01

This Australian study examined the communication, academic, and social outcomes of pediatric cochlear implantation from the perspectives of teachers working with children with cochlear implants. The children were aged from 1 to 18 years and attended a range of educational settings in early intervention, primary, and secondary schooling. One…

Cochlear Implants in Children with Hearing Loss: Maternal Expectations and Impact on the Family

ERIC Educational Resources Information Center

Zaidman-Zait, Anat; Most, Tova

2005-01-01

To facilitate evaluations of cochlear implant candidates and to promote (re)habilitation efficacy and collaboration with families, this study examined the expectations of 35 mothers with typical hearing and their beliefs and difficulties related to their child's hearing loss and current or future cochlear implantation. Questionnaires measured…

Persistent Language Delay versus Late Language Emergence in Children with Early Cochlear Implantation

ERIC Educational Resources Information Center

Geers, Ann E.; Nicholas, Johanna; Tobey, Emily; Davidson, Lisa

2016-01-01

Purpose: The purpose of the present investigation is to differentiate children using cochlear implants (CIs) who did or did not achieve age-appropriate language scores by mid-elementary grades and to identify risk factors for persistent language delay following early cochlear implantation. Materials and Method: Children receiving unilateral CIs at…

Serving Deaf Students Who Have Cochlear Implants. PEPNet Tipsheet

ERIC Educational Resources Information Center

Searls, J. Matt, Comp.

2010-01-01

Cochlear implants (CIs) are complex electronic devices surgically implanted under the skin behind the ear. These devices utilize electrodes placed in the inner ear (the cochlea) to stimulate the auditory nerve of individuals with significant permanent hearing loss. Cochlear implants may not be suitable for everyone. They are designed to provide…

Verbal Working Memory in Children with Cochlear Implants

ERIC Educational Resources Information Center

Nittrouer, Susan; Caldwell-Tarr, Amanda; Low, Keri E.; Lowenstein, Joanna H.

2017-01-01

Purpose: Verbal working memory in children with cochlear implants and children with normal hearing was examined. Participants: Ninety-three fourth graders (47 with normal hearing, 46 with cochlear implants) participated, all of whom were in a longitudinal study and had working memory assessed 2 years earlier. Method: A dual-component model of…

Emotion Understanding in Deaf Children with a Cochlear Implant

ERIC Educational Resources Information Center

Wiefferink, Carin H.; Rieffe, Carolien; Ketelaar, Lizet; De Raeve, Leo; Frijns, Johan H. M.

2013-01-01

It is still largely unknown how receiving a cochlear implant affects the emotion understanding in deaf children. We examined indices for emotion understanding and their associations with communication skills in children aged 2.5-5 years, both hearing children (n = 52) and deaf children with a cochlear implant (n = 57). 2 aspects of emotion…

Evaluating the Feasibility of Using Remote Technology for Cochlear Implants

ERIC Educational Resources Information Center

Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.

2012-01-01

The use of remote technology to provide cochlear implant services has gained popularity in recent years. This article contains a review of research evaluating the feasibility of remote service delivery for recipients of cochlear implants. To date, published studies have determined that speech-processor programming levels and other objective tests…

Scala tympani cochleostomy I: results of a survey.

PubMed

Adunka, Oliver F; Buchman, Craig A

2007-12-01

To assess current surgical techniques for scala tympani cochlear implantation among North American surgeons. A survey was distributed to all cochlear implant surgeons participating in the 2006 William House Cochlear Implant Study Group in Toronto, Canada. Participants were asked to anonymously identify their routine surgical practices. Images of trans-facial recess approaches to the round window and cochlear promontory were used in a multiple-choice fashion to assess the surgeon's typical exposure and cochleostomy location. Returned questionnaires were electronically processed and evaluated. Fifty-five (75%) of 73 returned surveys had adequate data validity and availability. Landmark identification and preferred cochleostomy locations varied greatly. About 20% of surgeons selected cochleostomy locations superior to the round window membrane. Cochleostomy size and location appeared to be influenced by surgical experience and whether or not the round window overhang was drilled off. This survey clearly documents marked variations in surgical techniques for scala tympani cochlear implantation. Future studies should more clearly define the surgical anatomy of this region for appropriate placement of a scala tympani cochleostomy. These findings may ultimately have an impact on hearing and neural preservation cochlear implant surgeries.

Comparison of intelligence quotients of first- and second-generation deaf children with cochlear implants.

PubMed

Amraei, K; Amirsalari, S; Ajalloueyan, M

2017-01-01

Hearing impairment is a common type of sensory loss in children. Studies indicate that children with hearing impairment are deficient in social, cognitive and communication skills. This study compared the intelligence quotients of first- and second-generation deaf children with cochlear implants. This research is causal-comparative. All 15 deaf children investigated had deaf parents and were selected from Baqiyatallah Cochlear Implant Center. The 15 children with cochlear implants were paired with similar children with hearing parents using purposive sampling. The findings show that the Hotelling trace of multivariate analysis of variance (F = 6.78, p < 0.01, η P 2  = 0.73) was significant. The tests of between-subjects effects for second-generation children was significantly higher than for first-generation children for all intelligence scales except knowledge. It can be assumed that second-generation children joined their family in the use of sign language as the primary experience before a cochlear implant. The use of sign language before cochlear implants is recommended. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Cochlear Implants and Psychiatric Assessments: a Norrie Disease Case Report.

PubMed

Jacques, Denis; Dubois, Thomas; Zdanowicz, Nicolas; Gilain, Chantal; Garin, Pierre

2017-09-01

It is important to perform psychiatric assessments of adult patients who are candidates for cochlear implants both to screen them for psychiatric disorders and to assess their understanding and compliance with the procedure. Deafness is a factor of difficulty for conducting in-depth psychiatric interviews, but concomitant blindness may make it impossible. After a description of Norrie disease, a rare disease in which blindness and deafness may occur together, we propose a case report of a patient suffering from the disease and who consulted in view of a cochlear implant. Early information on cochlear implants appears to be necessary before total deafness occurs in patients suffering from Norrie disease. An inventory of digital communication tools that can be used by the patient is also highly valuable. Research should be supported for a more systematic use of psychiatric assessments prior to cochlear implants. In the special case of Norrie disease, we recommend early screening for mental retardation and related psychotic disorders and, depending on the patient's level of understanding, preventive information on the benefits and limits of cochlear implants before total deafness occurs.

Evaluation of a cochlear-implant processing strategy incorporating phantom stimulation and asymmetric pulses

PubMed Central

Monstrey, Jolijn; Deeks, John M.; Macherey, Olivier

2014-01-01

Objective To evaluate a speech-processing strategy in which the lowest frequency channel is conveyed using an asymmetric pulse shape and “phantom stimulation”, where current is injected into one intra-cochlear electrode and where the return current is shared between an intra-cochlear and an extra-cochlear electrode. This strategy is expected to provide more selective excitation of the cochlear apex, compared to a standard strategy where the lowest-frequency channel is conveyed by symmetric pulses in monopolar mode. In both strategies all other channels were conveyed by monopolar stimulation. Design Within-subjects comparison between the two strategies. Four experiments: (1) discrimination between the strategies, controlling for loudness differences, (2) consonant identification, (3) recognition of lowpass-filtered sentences in quiet, (4) sentence recognition in the presence of a competing speaker. Study sample Eight users of the Advanced Bionics CII/Hi-Res 90k cochlear implant. Results Listeners could easily discriminate between the two strategies but no consistent differences in performance were observed. Conclusions The proposed method does not improve speech perception, at least in the short term. PMID:25358027

Evaluation of a cochlear-implant processing strategy incorporating phantom stimulation and asymmetric pulses.

PubMed

Carlyon, Robert P; Monstrey, Jolijn; Deeks, John M; Macherey, Olivier

2014-12-01

To evaluate a speech-processing strategy in which the lowest frequency channel is conveyed using an asymmetric pulse shape and "phantom stimulation", where current is injected into one intra-cochlear electrode and where the return current is shared between an intra-cochlear and an extra-cochlear electrode. This strategy is expected to provide more selective excitation of the cochlear apex, compared to a standard strategy where the lowest-frequency channel is conveyed by symmetric pulses in monopolar mode. In both strategies all other channels were conveyed by monopolar stimulation. Within-subjects comparison between the two strategies. Four experiments: (1) discrimination between the strategies, controlling for loudness differences, (2) consonant identification, (3) recognition of lowpass-filtered sentences in quiet, (4) sentence recognition in the presence of a competing speaker. Eight users of the Advanced Bionics CII/Hi-Res 90k cochlear implant. Listeners could easily discriminate between the two strategies but no consistent differences in performance were observed. The proposed method does not improve speech perception, at least in the short term.

Bringing Hearing to the Deaf

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shipsey, Ian

In his talk, Shipsey will discuss the cochlear implant, the first device to successfully allow the profoundly deaf to regain some sense of hearing. A cochlear implant is a small electronic apparatus. Unlike a normal hearing aid, which amplifies sound, a cochlear implant is surgically implanted behind the ear where it converts sound waves into electrical impulses. These implants have instigated a popular but controversial revolution in the treatment of deafness, and they serve as a model for research in neuroscience and biomedical engineering. Shipsey will discuss the physiology of natural hearing from the perspective of a physicist. He willmore » also touch on the function of cochlear implants in the context of historical treatments, electrical engineering, psychophysics, clinical evaluation of efficacy and personal experience. Finally, Shipsey will address the social implications of cochlear implantation and the future outlook for auditory prostheses.« less

Effect of age at cochlear implantation on auditory and speech development of children with auditory neuropathy spectrum disorder.

PubMed

Liu, Yuying; Dong, Ruijuan; Li, Yuling; Xu, Tianqiu; Li, Yongxin; Chen, Xueqing; Gong, Shusheng

2014-12-01

To evaluate the auditory and speech abilities in children with auditory neuropathy spectrum disorder (ANSD) after cochlear implantation (CI) and determine the role of age at implantation. Ten children participated in this retrospective case series study. All children had evidence of ANSD. All subjects had no cochlear nerve deficiency on magnetic resonance imaging and had used the cochlear implants for a period of 12-84 months. We divided our children into two groups: children who underwent implantation before 24 months of age and children who underwent implantation after 24 months of age. Their auditory and speech abilities were evaluated using the following: behavioral audiometry, the Categories of Auditory Performance (CAP), the Meaningful Auditory Integration Scale (MAIS), the Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS), the Standard-Chinese version of the Monosyllabic Lexical Neighborhood Test (LNT), the Multisyllabic Lexical Neighborhood Test (MLNT), the Speech Intelligibility Rating (SIR) and the Meaningful Use of Speech Scale (MUSS). All children showed progress in their auditory and language abilities. The 4-frequency average hearing level (HL) (500Hz, 1000Hz, 2000Hz and 4000Hz) of aided hearing thresholds ranged from 17.5 to 57.5dB HL. All children developed time-related auditory perception and speech skills. Scores of children with ANSD who received cochlear implants before 24 months tended to be better than those of children who received cochlear implants after 24 months. Seven children completed the Mandarin Lexical Neighborhood Test. Approximately half of the children showed improved open-set speech recognition. Cochlear implantation is helpful for children with ANSD and may be a good optional treatment for many ANSD children. In addition, children with ANSD fitted with cochlear implants before 24 months tended to acquire auditory and speech skills better than children fitted with cochlear implants after 24 months. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Tinnitus after Simultaneous and Sequential Bilateral Cochlear Implantation.

PubMed

Ramakers, Geerte G J; Kraaijenga, Véronique J C; Smulders, Yvette E; van Zon, Alice; Stegeman, Inge; Stokroos, Robert J; Free, Rolien H; Frijns, Johan H M; Huinck, Wendy J; Van Zanten, Gijsbert A; Grolman, Wilko

2017-01-01

There is an ongoing global discussion on whether or not bilateral cochlear implantation should be standard care for bilateral deafness. Contrary to unilateral cochlear implantation, however, little is known about the effect of bilateral cochlear implantation on tinnitus. To investigate tinnitus outcomes 1 year after bilateral cochlear implantation. Secondarily, to compare tinnitus outcomes between simultaneous and sequential bilateral cochlear implantation and to investigate long-term follow-up (3 years). This study is a secondary analysis as part of a multicenter randomized controlled trial. Thirty-eight postlingually deafened adults were included in the original trial, in which the presence of tinnitus was not an inclusion criterion. All participants received cochlear implants (CIs) because of profound hearing loss. Nineteen participants received bilateral CIs simultaneously and 19 participants received bilateral CIs sequentially with an inter-implant interval of 2 years. The prevalence and severity of tinnitus before and after simultaneous and sequential bilateral cochlear implantation were measured preoperatively and each year after implantation with the Tinnitus Handicap Inventory (THI) and Tinnitus Questionnaire (TQ). The prevalence of preoperative tinnitus was 42% (16/38). One year after bilateral implantation, there was a median difference of -8 (inter-quartile range (IQR): -28 to 4) in THI score and -9 (IQR: -17 to -9) in TQ score in the participants with preoperative tinnitus. Induction of tinnitus occurred in five participants, all in the simultaneous group, in the year after bilateral implantation. Although the preoperative and also the postoperative median THI and TQ scores were higher in the simultaneous group, the median difference scores were equal in both groups. In the simultaneous group, tinnitus scores fluctuated in the 3 years after implantation. In the sequential group, four patients had an additional benefit of the second CI: a total suppression of tinnitus compared with their unilateral situation. While bilateral cochlear implantation can have a positive effect on preoperative tinnitus complaints, the induction of (temporary or permanent) tinnitus was also reported. Dutch Trial Register NTR1722.

[Effect of rehabilitation for prelingual deaf children who use cochlear implants in conjunction with hearing aids in the opposite ears].

PubMed

Tian, Yanjing; Zhou, Huifang; Zhang, Jing; Yang, Dong; Xu, Yi; Guo, Yuxi

2012-10-01

To compare the effect of rehabilitation of prelingual deaf children who used a cochlear implant (CI) in one ear and a hearing aids in the opposite ear while the hearing level of the opposite ears are different. Hearing ability, language ability and learning ability was included in the content. The aim of this research is to investigate better style of rehabilitation, and to offer the best help to the prelingual deaf children. Accord ing to the hearing level of the ear opposite to the one wearing a cochlear implant and whether the opposite ear wear a hearing aid or not, 30 prelingual deaf children were divided into three groups, including cochlear implant with opposite severe hearing loss and hearing aid ear (CI+SHA), cochlear implant with opposite profound hearing loss and hearing aid ear (CI+PHA), cochlear implant only (CI). The effect of rehabilitation was assessed in six different times (3,6,9,12,15 and 18 months after the cochlear implants and hearing aids began to work). The longer time the rehabilitation spends, the better the hearing ability,language ability and the learning ability were. The hearing ability of CI+SHA was better than those of CI+PHA (P<0.05) and CI (P<0.05). The language ability and learning ability of CI-SHA was nearly equal to those of the other two groups. The prelingual deaf children should take much more time on rehabilitation. The effect of rehabilitation for prelingual deaf children who used cochlear implant in one ear and hearing aid in the other depend on the residual hearing level of the other ear. If a prelingual deaf children still has any residual hearing level in the ear opposite to the cochlear implant ear, it is better for him/her to wear a hearing aid in the ear.

Altered vesicular glutamate transporter distributions in the mouse cochlear nucleus following cochlear insult

PubMed Central

Heeringa, Amarins N.; Stefanescu, Roxana A.; Raphael, Yehoash; Shore, Susan E.

2015-01-01

Vesicular glutamate transporters 1 and 2 (VGLUT1 and VGLUT2) have distinct distributions in the cochlear nucleus that correspond to the sources of the labeled terminals. VGLUT1 is mainly associated with terminals of auditory nerve fibers, whereas VGLUT2 is mainly associated with glutamatergic terminals deriving from other sources that project to the cochlear nucleus (CN), including somatosensory and vestibular terminals. Previous studies in guinea pig have shown that cochlear damage results in a decrease of VGLUT1-labeled puncta and an increase in VGLUT2-labeled puncta. This indicates cross-modal compensation that is of potential importance in somatic tinnitus. To examine whether this effect is consistent across species and to provide a background for future studies, using transgenesis, the current study examines VGLUT expression profiles upon cochlear insult by intracochlear kanamycin injections in the mouse. Intracochlear kanamycin injections abolished ipsilateral ABR responses in all animals and reduced ipsilateral spiral ganglion neuron densities in animals that were sacrificed after four weeks, but not in animals that were sacrificed after three weeks. In all unilaterally deafened animals, VGLUT1 density was decreased in CN regions that receive auditory nerve fiber terminals, i.e. in the deep layer of the dorsal cochlear nucleus (DCN), in the interstitial region where the auditory nerve enters the CN, and in the magnocellular region of the antero- and posteroventral CN. In contrast, density of VGLUT2 expression was upregulated in the fusiform cell layer of the DCN and in the granule cell lamina, which are known to receive somatosensory and vestibular terminals. These results show that a cochlear insult induces cross-modal compensation in the cochlear nucleus of the mouse, confirming previous findings in guinea pig, and that these changes are not dependent on the occurrence of spiral ganglion neuron degeneration. PMID:26705736

Altered vesicular glutamate transporter distributions in the mouse cochlear nucleus following cochlear insult.

PubMed

Heeringa, A N; Stefanescu, R A; Raphael, Y; Shore, S E

2016-02-19

Vesicular glutamate transporters 1 and 2 (VGLUT1 and VGLUT2) have distinct distributions in the cochlear nucleus that correspond to sources of the labeled terminals. VGLUT1 is mainly associated with terminals of auditory nerve fibers, whereas VGLUT2 is mainly associated with glutamatergic terminals deriving from other sources that project to the cochlear nucleus (CN), including somatosensory and vestibular terminals. Previous studies in guinea pig have shown that cochlear damage results in a decrease of VGLUT1-labeled puncta and an increase in VGLUT2-labeled puncta. This indicates cross-modal compensation that is of potential importance in somatic tinnitus. To examine whether this effect is consistent across species and to provide a background for future studies, using transgenesis, the current study examines VGLUT expression profiles upon cochlear insult by intracochlear kanamycin injections in the mouse. Intracochlear kanamycin injections abolished ipsilateral ABR responses in all animals and reduced ipsilateral spiral ganglion neuron densities in animals that were sacrificed after four weeks, but not in animals that were sacrificed after three weeks. In all unilaterally deafened animals, VGLUT1 density was decreased in CN regions that receive auditory nerve fiber terminals, i.e., in the deep layer of the dorsal cochlear nucleus (DCN), in the interstitial region where the auditory nerve enters the CN, and in the magnocellular region of the antero- and posteroventral CN. In contrast, density of VGLUT2 expression was upregulated in the fusiform cell layer of the DCN and in the granule cell lamina, which are known to receive somatosensory and vestibular terminals. These results show that a cochlear insult induces cross-modal compensation in the cochlear nucleus of the mouse, confirming previous findings in guinea pig, and that these changes are not dependent on the occurrence of spiral ganglion neuron degeneration. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Bringing Hearing to the Deaf--Cochlear Implants: a Technical and Personal Account

NASA Astrophysics Data System (ADS)

Shipsey, Ian

2006-04-01

Cochlear implants are the first device to successfully restore neural function. They have instigated a popular but controversial revolution in the treatment of deafness, and they serve as a model for research in neuroscience and biomedical engineering. In this talk the physiology of natural hearing will be reviewed from the perspective of a physicist, and the function of cochlear implants will be described in the context of historical treatments, electrical engineering, psychophysics, clinical evaluation of efficacy and personal experience. The social implications of cochlear implantation and the future outlook for auditory prostheses will also be discussed.

Microphone directionality, pre-emphasis filter, and wind noise in cochlear implants.

PubMed

Chung, King; McKibben, Nicholas

2011-10-01

Wind noise can be a nuisance or a debilitating masker for cochlear implant users in outdoor environments. Previous studies indicated that wind noise at the microphone/hearing aid output had high levels of low-frequency energy and the amount of noise generated is related to the microphone directionality. Currently, cochlear implants only offer either directional microphones or omnidirectional microphones for users at-large. As all cochlear implants utilize pre-emphasis filters to reduce low-frequency energy before the signal is encoded, effective wind noise reduction algorithms for hearing aids might not be applicable for cochlear implants. The purposes of this study were to investigate the effect of microphone directionality on speech recognition and perceived sound quality of cochlear implant users in wind noise and to derive effective wind noise reduction strategies for cochlear implants. A repeated-measure design was used to examine the effects of spectral and temporal masking created by wind noise recorded through directional and omnidirectional microphones and the effects of pre-emphasis filters on cochlear implant performance. A digital hearing aid was programmed to have linear amplification and relatively flat in-situ frequency responses for the directional and omnidirectional modes. The hearing aid output was then recorded from 0 to 360° at flow velocities of 4.5 and 13.5 m/sec in a quiet wind tunnel. Sixteen postlingually deafened adult cochlear implant listeners who reported to be able to communicate on the phone with friends and family without text messages participated in the study. Cochlear implant users listened to speech in wind noise recorded at locations that the directional and omnidirectional microphones yielded the lowest noise levels. Cochlear implant listeners repeated the sentences and rated the sound quality of the testing materials. Spectral and temporal characteristics of flow noise, as well as speech and/or noise characteristics before and after the pre-emphasis filter, were analyzed. Correlation coefficients between speech recognition scores and crest factors of wind noise before and after pre-emphasis filtering were also calculated. Listeners obtained higher scores using the omnidirectional than the directional microphone mode at 13.5 m/sec, but they obtained similar speech recognition scores for the two microphone modes at 4.5 m/sec. Higher correlation coefficients were obtained between speech recognition scores and crest factors of wind noise after pre-emphasis filtering rather than before filtering. Cochlear implant users would benefit from both directional and omnidirectional microphones to reduce far-field background noise and near-field wind noise. Automatic microphone switching algorithms can be more effective if the incoming signal were analyzed after pre-emphasis filters for microphone switching decisions. American Academy of Audiology.

Exploring the Language and Literacy Outcomes of Pediatric Cochlear Implant Users

PubMed Central

Spencer, Linda J.; Barker, Brittan A.; Tomblin, J. Bruce

2011-01-01

Objective The principal goal of this study was to investigate the relationship between language and literacy (i.e., reading and writing) skills in pediatric cochlear implant users. A peripheral objective was to identify the children's skills that were in need of remediation and subsequently to provide suggestions for remedial programming. It was predicted that the robust language skills often associated with children who have cochlear implant experience would facilitate the development of literacy skills. It was further proposed that the language and literacy skills of pediatric cochlear implant users would approximate the language and literacy skills of children with normal hearing. Design Sixteen pediatric cochlear implant users' language and literacy skills were evaluated and then compared with a reference group of 16 age-matched, normal-hearing children. All 32 participants were educated in mainstream classes within the public school system in the Midwest. The “Sentence Formulation” and “Concepts and Directions” subtests of the Clinical Evaluation of Language Fundamentals-3 test were used to evaluate receptive and expressive language skills. Reading comprehension was evaluated with the “Paragraph Comprehension” subtest of the Woodcock Reading Mastery Test. Performance measures for the writing analyses included productivity, complexity and grammaticality measures. Results Children with cochlear implants performed within 1 SD of the normal-hearing, age-matched children on measures of language comprehension, reading comprehension and writing accuracy. However, the children with cochlear implants performed significantly poorer than the children with normal hearing on the expressive “Sentence Formulation” subtest. The cochlear implant users also produced fewer words on the written narrative task than did the normal-hearing children, although there was not a significant difference between groups with respect to total words per clause. Furthermore there was a strong correlation between language performance and reading performance, as well as language performance and total words produced on the written performance measure for the children using cochlear implants. Conclusions The results of this study suggest that the language skills of pediatric cochlear implant users are related to and correlated with the development of literacy skills within these children. Consequently, the performance of the cochlear implant users, on various language and literacy measures, compared favorably to an age-matched group of children with normal hearing. There were significant differences in the ability of the cochlear implant users to correctly utilize grammatical structures such as conjunctions and correct verb forms when they were required to formulate written and oral sentences. Given this information, it would be appropriate for their educational or remedial language programs to emphasize the use and development of these structures. PMID:12799546

Cochlear implants and ex vivo BDNF gene therapy protect spiral ganglion neurons.

PubMed

Rejali, Darius; Lee, Valerie A; Abrashkin, Karen A; Humayun, Nousheen; Swiderski, Donald L; Raphael, Yehoash

2007-06-01

Spiral ganglion neurons often degenerate in the deaf ear, compromising the function of cochlear implants. Cochlear implant function can be improved by good preservation of the spiral ganglion neurons, which are the target of electrical stimulation by the implant. Brain derived neurotrophic factor (BDNF) has previously been shown to enhance spiral ganglion survival in experimentally deafened ears. Providing enhanced levels of BDNF in human ears may be accomplished by one of several different methods. The goal of these experiments was to test a modified design of the cochlear implant electrode that includes a coating of fibroblast cells transduced by a viral vector with a BDNF gene insert. To accomplish this type of ex vivo gene transfer, we transduced guinea pig fibroblasts with an adenovirus with a BDNF gene cassette insert, and determined that these cells secreted BDNF. We then attached BDNF-secreting cells to the cochlear implant electrode via an agarose gel, and implanted the electrode in the scala tympani. We determined that the BDNF expressing electrodes were able to preserve significantly more spiral ganglion neurons in the basal turns of the cochlea after 48 days of implantation when compared to control electrodes. This protective effect decreased in the higher cochlear turns. The data demonstrate the feasibility of combining cochlear implant therapy with ex vivo gene transfer for enhancing spiral ganglion neuron survival.

Is there a best side for cochlear implants in post-lingual patients?

PubMed

Amaral, Maria Stella Arantes do; Damico, Thiago A; Gonçales, Alina S; Reis, Ana C M B; Isaac, Myriam de Lima; Massuda, Eduardo T; Hyppolito, Miguel Angelo

2017-07-29

Cochlear Implant is a sensory prosthesis capable of restoring hearing in patients with severe or profound bilateral sensorineural hearing loss. To evaluate if there is a better side to be implanted in post-lingual patients. Retrospective longitudinal study. Participants were 40 subjects, of both sex, mean age of 47 years, with post-lingual hearing loss, users of unilateral cochlear implant for more than 12 months and less than 24 months, with asymmetric auditor reserve between the ears (difference of 10dBNA, In at least one of the frequencies with a response, between the ears), divided into two groups. Group A was composed of individuals with cochlear implant in the ear with better auditory reserve and Group B with auditory reserve lower in relation to the contralateral side. There was no statistical difference for the tonal auditory threshold before and after cochlear implant. A better speech perception in pre-cochlear implant tests was present in B (20%), but the final results are similar in both groups. The cochlear implant in the ear with the worst auditory residue favors a bimodal hearing, which would allow the binaural summation, without compromising the improvement of the audiometric threshold and the speech perception. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Cochlear implants and medical tourism.

PubMed

McKinnon, Brian J; Bhatt, Nishant

2010-09-01

To compare the costs of medical tourism in cochlear implant surgery performed in India as compared to the United States. In addition, the cost savings of obtaining cochlear implant surgery in India were compare d to those of other surgical interventions obtained as a medical tourist. Searches were conducted on Medline and Google using the search terms: 'medical tourism', 'medical offshoring', 'medical outsourcing', 'cochlear implants' and 'cochlear implantation'. The information regarding cost of medical treatment was obtained from personal communication with individuals familiar with India's cochlear implantation medical tourism industry. The range of cost depended on length of stay as well as the device chosen. Generally the cost, inclusive of travel, surgery and device, was in the range of $21,000-30,000, as compared to a cost range of $40,000-$60,000 in the US. With the escalating cost of healthcare in the United States, it is not surprising that some patients would seek to obtain surgical care overseas at a fraction of the cost. Participants in medical tourism often have financial resources, but lack health insurance coverage. While cardiovascular and orthopedic surgery performed outside the United States in India at centers that cater to medical tourists are often performed at one-quarter to one-third of the cost that would have been paid in the United States, the cost differential for cochlear implants is not nearly as favorable.

[Water regulation in the cochlea : Do molecular water channels facilitate potassium-dependent sound transduction?].

PubMed

Eckhard, A; Löwenheim, H

2014-06-01

Sound transduction in the cochlea critically depends on the circulation of potassium ions (K(+)) along so-called "K(+) recycling routes" between the endolymph and perilymph. These K(+) currents generate high ionic and osmotic gradients, which potentially impair the excitability of sensory hair cells and threaten cell survival in the entire cochlear duct. Molecular water channels-aquaporins (AQP)-are expressed in all cochlear supporting cells along the K(+) recycling routes; however, their significance for osmotic equilibration in cochlear duct cells is unknown. The diffusive and osmotic water permeabilies of Reissner's membrane, the organ of Corti and the entire cochlear duct epithelium were determined. Expression of the potassium channel Kir4.1 and the water channel AQP4 in the cochlear duct was investigated by immunohistochemistry. The calculated water permeability values indicate the extent of AQP-facilitated water flux across the cochlear duct epithelium. Immunohistochemically, Kir4.1 and AQP4 were found to colocalize in distinct membrane domains of supporting cells along the K(+)-recycling routes. These observations suggest the presence of a rapid AQP-mediated water exchange between the endolymph, the cells of the cochlear duct and the perilymph. The subcellular colocalization of Kir4.1 and AQP4 in epithelial supporting cells indicates functional coupling of potassium and water flow in the cochlea. Finally, this offers an explanation for the hearing impairment observed in individuals with mutations in the AQP4 gene.

Bilateral cochlear implantation in the ferret: A novel animal model for behavioral studies

PubMed Central

Hartley, Douglas E.H.; Vongpaisal, Tara; Xu, Jin; Shepherd, Robert K.; King, Andrew J.; Isaiah, Amal

2010-01-01

Bilateral cochlear implantation has recently been introduced with the aim of improving both speech perception in background noise and sound localization. Although evidence suggests that binaural perception is possible with two cochlear implants, results in humans are variable. To explore potential contributing factors to these variable outcomes, we have developed a behavioral animal model of bilateral cochlear implantation in a novel species, the ferret. Although ferrets are ideally suited to psychophysical and physiological assessments of binaural hearing, cochlear implantation has not been previously described in this species. This paper describes the techniques of deafening with aminoglycoside administration, surgical implantation of an intracochlear array and chronic intracochlear electrical stimulation with monitoring for electrode integrity and efficacy of stimulation. Experiments have been presented elsewhere to show that the model can be used to study behavioral and electrophysiological measures of binaural hearing in chronically implanted animals. This paper demonstrates that cochlear implantation and chronic intracochlear electrical stimulation are both safe and effective in ferrets, opening up the possibility of using this model to study potential protective effects of bilateral cochlear implantation on the developing central auditory pathway. Since ferrets can be used to assess psychophysical and physiological aspects of hearing along with the structure of the auditory pathway in the same animals, we anticipate that this model will help develop novel neuroprosthetic therapies for use in humans. PMID:20576507

Large vestibular aqueduct syndrome: Impedance changes over time with different cochlear implant electrode arrays.

PubMed

Powell, Harry R F; Birman, Catherine S

2015-01-01

The aim of this study was to assess if large vestibular aqueduct syndrome (LVAS), with the increase in perilymphatic pressure, affects impedance changes over time with different types of Cochlear(®) implant electrode arrays Contour, Straight, and CI 422. To report speech perception outcomes for these cochlear implant recipients. Retrospective case review of impedance levels and categories of auditory performance. Impedance data were collected at switch on, 1 month, 3, 6, 12, and 24 months after cochlear implantation and compared with control (non-LVAS cochlear implant recipient) data for each array type. Forty-seven patients with exclusive LVAS and no other vestibulocochlear abnormalities or other identifiable cause of deafness were eligible for inclusion in the study. In LVAS patients, there was a significant difference in impedance between the three types of device (P < 0.0001). Time since switch on was associated with a decrease in impedance for all three devices (P < 0.0001). The mean impedance reduced between switch on and 1 month and remained relatively constant thereafter. Sound variation with softening of sounds was seen in four CI 422 (Straight Research Array) recipients due to ongoing fluctuations in electrode compliance. For all three array types, there was no significant difference in the mean impedance between the LVAS patients and controls over the first 12 months. In keeping with previous studies cochlear implant recipients with LVAS hear very well through the cochlear implant.

The Influence of Cochlear Mechanical Dysfunction, Temporal Processing Deficits, and Age on the Intelligibility of Audible Speech in Noise for Hearing-Impaired Listeners

PubMed Central

Johannesen, Peter T.; Pérez-González, Patricia; Kalluri, Sridhar; Blanco, José L.

2016-01-01

The aim of this study was to assess the relative importance of cochlear mechanical dysfunction, temporal processing deficits, and age on the ability of hearing-impaired listeners to understand speech in noisy backgrounds. Sixty-eight listeners took part in the study. They were provided with linear, frequency-specific amplification to compensate for their audiometric losses, and intelligibility was assessed for speech-shaped noise (SSN) and a time-reversed two-talker masker (R2TM). Behavioral estimates of cochlear gain loss and residual compression were available from a previous study and were used as indicators of cochlear mechanical dysfunction. Temporal processing abilities were assessed using frequency modulation detection thresholds. Age, audiometric thresholds, and the difference between audiometric threshold and cochlear gain loss were also included in the analyses. Stepwise multiple linear regression models were used to assess the relative importance of the various factors for intelligibility. Results showed that (a) cochlear gain loss was unrelated to intelligibility, (b) residual cochlear compression was related to intelligibility in SSN but not in a R2TM, (c) temporal processing was strongly related to intelligibility in a R2TM and much less so in SSN, and (d) age per se impaired intelligibility. In summary, all factors affected intelligibility, but their relative importance varied across maskers. PMID:27604779

fMRI as a Preimplant Objective Tool to Predict Children's Postimplant Auditory and Language Outcomes as Measured by Parental Observations.

PubMed

Deshpande, Aniruddha K; Tan, Lirong; Lu, Long J; Altaye, Mekibib; Holland, Scott K

2018-05-01

The trends in cochlear implantation candidacy and benefit have changed rapidly in the last two decades. It is now widely accepted that early implantation leads to better postimplant outcomes. Although some generalizations can be made about postimplant auditory and language performance, neural mechanisms need to be studied to predict individual prognosis. The aim of this study was to use functional magnetic resonance imaging (fMRI) to identify preimplant neuroimaging biomarkers that predict children's postimplant auditory and language outcomes as measured by parental observation/reports. This is a pre-post correlational measures study. Twelve possible cochlear implant candidates with bilateral severe to profound hearing loss were recruited via referrals for a clinical magnetic resonance imaging to ensure structural integrity of the auditory nerve for implantation. Participants underwent cochlear implantation at a mean age of 19.4 mo. All children used the advanced combination encoder strategy (ACE, Cochlear Corporation™, Nucleus ® Freedom cochlear implants). Three participants received an implant in the right ear; one in the left ear whereas eight participants received bilateral implants. Participants' preimplant neuronal activation in response to two auditory stimuli was studied using an event-related fMRI method. Blood oxygen level dependent contrast maps were calculated for speech and noise stimuli. The general linear model was used to create z-maps. The Auditory Skills Checklist (ASC) and the SKI-HI Language Development Scale (SKI-HI LDS) were administered to the parents 2 yr after implantation. A nonparametric correlation analysis was implemented between preimplant fMRI activation and postimplant auditory and language outcomes based on ASC and SKI-HI LDS. Statistical Parametric Mapping software was used to create regression maps between fMRI activation and scores on the aforementioned tests. Regression maps were overlaid on the Imaging Research Center infant template and visualized in MRIcro. Regression maps revealed two clusters of brain activation for the speech versus silence contrast and five clusters for the noise versus silence contrast that were significantly correlated with the parental reports. These clusters included auditory and extra-auditory regions such as the middle temporal gyrus, supramarginal gyrus, precuneus, cingulate gyrus, middle frontal gyrus, subgyral, and middle occipital gyrus. Both positive and negative correlations were observed. Correlation values for the different clusters ranged from -0.90 to 0.95 and were significant at a corrected p value of <0.05. Correlations suggest that postimplant performance may be predicted by activation in specific brain regions. The results of the present study suggest that (1) fMRI can be used to identify neuroimaging biomarkers of auditory and language performance before implantation and (2) activation in certain brain regions may be predictive of postimplant auditory and language performance as measured by parental observation/reports. American Academy of Audiology.

Parents' Views on Changing Communication after Cochlear Implantation

ERIC Educational Resources Information Center

Watson, Linda M.; Hardie, Tim; Archbold, Sue M.; Wheeler, Alexandra

2008-01-01

We sent questionnaires to families of all 288 children who had received cochlear implants at one center in the United Kingdom at least 5 years previously. Thus, it was a large, unselected group. We received 142 replies and 119 indicated that the child and family had changed their communication approach following cochlear implantation. In 113 cases…

Changes in Speech Production in an Early Deafened Adult with a Cochlear Implant

ERIC Educational Resources Information Center

Wong, Patrick C. M.

2007-01-01

Background and Aims: The current study is a first investigation reporting the speech production characteristics of an early deafened adult cochlear implant user after a course of speech-language treatment. Methods and Procedures: The participant is culturally deaf and received the cochlear implant when she was 43 years old. A 24-week ABCABC…

The Self-Regulation of a Child with Cochlear Implants within a School Environment

ERIC Educational Resources Information Center

Patton, Kristin L.

2013-01-01

The purpose of this qualitative research, which utilized a narrative design strategy, was to describe the process of self-regulation of a child who has bilateral cochlear implants within the social environment of school. The study investigated the use of self-regulatory strategies by the cochlear implant recipient. It also examined how the child…

Cochlear Implantation for Children with Hearing Loss and Multiple Disabilities: An Evaluation from an Educator's Perspective

ERIC Educational Resources Information Center

Bertram, Bodo

2004-01-01

In recent years, parents of children with hearing loss and various additional disabilities have shown increasing interest in cochlear implants. This article describes how the program in Hanover, Germany is attempting to respond to this interest. It discusses the selection process for children who receive cochlear implants who have multiple…

Spelling in Written Stories by School-Age Children with Cochlear Implants

ERIC Educational Resources Information Center

Straley, Sara G.; Werfel, Krystal L.; Hendricks, Alison Eisel

2016-01-01

This study evaluated the spelling of 3rd to 6th grade children with cochlear implants in written stories. Spelling was analysed using traditional correct/incorrect scoring as well as the Spelling Sensitivity Score, which provides linguistic information about spelling attempts. Children with cochlear implants spelled 86 per cent of words in stories…

Identification of Pure-Tone Audiologic Thresholds for Pediatric Cochlear Implant Candidacy: A Systematic Review.

PubMed

de Kleijn, Jasper L; van Kalmthout, Ludwike W M; van der Vossen, Martijn J B; Vonck, Bernard M D; Topsakal, Vedat; Bruijnzeel, Hanneke

2018-05-24

Although current guidelines recommend cochlear implantation only for children with profound hearing impairment (HI) (>90 decibel [dB] hearing level [HL]), studies show that children with severe hearing impairment (>70-90 dB HL) could also benefit from cochlear implantation. To perform a systematic review to identify audiologic thresholds (in dB HL) that could serve as an audiologic candidacy criterion for pediatric cochlear implantation using 4 domains of speech and language development as independent outcome measures (speech production, speech perception, receptive language, and auditory performance). PubMed and Embase databases were searched up to June 28, 2017, to identify studies comparing speech and language development between children who were profoundly deaf using cochlear implants and children with severe hearing loss using hearing aids, because no studies are available directly comparing children with severe HI in both groups. If cochlear implant users with profound HI score better on speech and language tests than those with severe HI who use hearing aids, this outcome could support adjusting cochlear implantation candidacy criteria to lower audiologic thresholds. Literature search, screening, and article selection were performed using a predefined strategy. Article screening was executed independently by 4 authors in 2 pairs; consensus on article inclusion was reached by discussion between these 4 authors. This study is reported according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Title and abstract screening of 2822 articles resulted in selection of 130 articles for full-text review. Twenty-one studies were selected for critical appraisal, resulting in selection of 10 articles for data extraction. Two studies formulated audiologic thresholds (in dB HLs) at which children could qualify for cochlear implantation: (1) at 4-frequency pure-tone average (PTA) thresholds of 80 dB HL or greater based on speech perception and auditory performance subtests and (2) at PTA thresholds of 88 and 96 dB HL based on a speech perception subtest. In 8 of the 18 outcome measures, children with profound HI using cochlear implants performed similarly to children with severe HI using hearing aids. Better performance of cochlear implant users was shown with a picture-naming test and a speech perception in noise test. Owing to large heterogeneity in study population and selected tests, it was not possible to conduct a meta-analysis. Studies indicate that lower audiologic thresholds (≥80 dB HL) than are advised in current national and manufacturer guidelines would be appropriate as audiologic candidacy criteria for pediatric cochlear implantation.

Modeling Open-Set Spoken Word Recognition in Postlingually Deafened Adults after Cochlear Implantation: Some Preliminary Results with the Neighborhood Activation Model

PubMed Central

Meyer, Ted A.; Frisch, Stefan A.; Pisoni, David B.; Miyamoto, Richard T.; Svirsky, Mario A.

2012-01-01

Hypotheses Do cochlear implants provide enough information to allow adult cochlear implant users to understand words in ways that are similar to listeners with acoustic hearing? Can we use a computational model to gain insight into the underlying mechanisms used by cochlear implant users to recognize spoken words? Background The Neighborhood Activation Model has been shown to be a reasonable model of word recognition for listeners with normal hearing. The Neighborhood Activation Model assumes that words are recognized in relation to other similar-sounding words in a listener’s lexicon. The probability of correctly identifying a word is based on the phoneme perception probabilities from a listener’s closed-set consonant and vowel confusion matrices modified by the relative frequency of occurrence of the target word compared with similar-sounding words (neighbors). Common words with few similar-sounding neighbors are more likely to be selected as responses than less common words with many similar-sounding neighbors. Recent studies have shown that several of the assumptions of the Neighborhood Activation Model also hold true for cochlear implant users. Methods Closed-set consonant and vowel confusion matrices were obtained from 26 postlingually deafened adults who use cochlear implants. Confusion matrices were used to represent input errors to the Neighborhood Activation Model. Responses to the different stimuli were then generated by the Neighborhood Activation Model after incorporating the frequency of occurrence counts of the stimuli and their neighbors. Model outputs were compared with obtained performance measures on the Consonant-Vowel Nucleus-Consonant word test. Information transmission analysis was used to assess whether the Neighborhood Activation Model was able to successfully generate and predict word and individual phoneme recognition by cochlear implant users. Results The Neighborhood Activation Model predicted Consonant-Vowel Nucleus-Consonant test words at levels similar to those correctly identified by the cochlear implant users. The Neighborhood Activation Model also predicted phoneme feature information well. Conclusion The results obtained suggest that the Neighborhood Activation Model provides a reasonable explanation of word recognition by postlingually deafened adults after cochlear implantation. It appears that multichannel cochlear implants give cochlear implant users access to their mental lexicons in a manner that is similar to listeners with acoustic hearing. The lexical properties of the test stimuli used to assess performance are important to spoken-word recognition and should be included in further models of the word recognition process. PMID:12851554

Evaluation on health-related quality of life in deaf children with cochlear implant in China.

PubMed

Liu, Hong; Liu, Hong-Xiang; Kang, Hou-Yong; Gu, Zheng; Hong, Su-Ling

2016-09-01

Previous studies have shown that deaf children benefit considerably from cochlear implants. These improvements are found in areas such as speech perception, speech production, and audiology-verbal performance. Despite the increasing prevalence of cochlear implants in China, few studies have reported on health-related quality of life in children with cochlear implants. The main objective of this study was to explore health-related quality of life on children with cochlear implants in South-west China. A retrospective observational study of 213 CI users in Southwest China between 2010 and 2013. Participants were 213 individuals with bilateral severe-to-profound hearing loss who wore unilateral cochlear implants. The Nijmegen Cochlear Implant Questionnaire and Health Utility Index Mark III were used pre-implantation and 1 year post-implantation. Additionally, 1-year postoperative scores for Mandarin speech perception were compared with preoperative scores. Health-related quality of life improved post-operation with scores on the Nijmegen Cochlear Implant Questionnaire improving significantly in all subdomains, and the Health Utility Index 3 showing a significant improvement in the utility score and the subdomains of ''hearing," ''speech," and "emotion". Additionally, a significant improvement in speech recognition scores was found. No significant correlation was found between increased in quality of life and speech perception scores. Health-related quality of life and speech recognition in prelingual deaf children significantly improved post-operation. The lack of correlation between quality of life and speech perception suggests that when evaluating performance post-implantation in prelingual deaf children and adolescents, measures of both speech perception and quality of life should be used. Copyright © 2016. Published by Elsevier Ireland Ltd.

Jervell and Lange-Nielsen syndrome in cochlear implanted patients: our experience and a review of literature.

PubMed

Eftekharian, Ali; Mahani, Mozhgan Hosseinerezai

2015-09-01

To share our experience in cochlear implanted patients with Jervell and Lange-Nielsen syndrome (JLNS), to review the literature results and to disclose precautions which have to be taken dealing with these patients. Electrocardiograms (ECG) of 503 children with congenital bilateral profound hearing loss which were cochlear implanted in cochlear implant center of a tertiary hospital were evaluated for long QT syndrome. Clinical reports of the patients with JLNS were evaluated and a review of literature performed. The prevalence of disease was 0.79% (four cases) in our center which is in the range of literature reports (0-2.6%). None of our patients had a history of syncopal attack. Two patients (50%) were born from parents with consanguineous marriage. Considering all precautions their cochlear implant surgeries were done uneventfully. A review of the literature has identified sixteen reports on cochlear implantation in a total of 38 children with JLNS. Similar to our cases none of the authors reported cardiac events during device switch-on. Nine available reports about the outcome of cochlear implantation in these patients indicated good auditory outcome. It is recommended that all congenitally deaf patients have an ECG taken as a part of the evaluation. As auditory stimuli is reported to be a specific trigger, it is prudent to activate the processor with continuous heart monitoring even though there is no reported cardiac event during device switch-on. Cochlear implantation can be performed relatively safely in these patients if necessary precautions have been taken appropriately and their auditory outcome is good. Triggers of the cardiac events should be avoided throughout their life. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Assessment of the cochlear nerve to facial nerve size ratio using MR multiplanar reconstruction of the internal auditory canal in patients presenting with acquired long-standing hearing loss

PubMed Central

Hey, Constanze; Shaaban, Mohamed S; Elabd, Amr M; Hassan, Hebatallah H M; Gruber-Rouh, Tatjana; Kaltenbach, Benjamin; Harth, Marc; Ackermann, Hanns; Stöver, Timo; Vogl, Thomas J; Nour-Eldin, Nour-Eldin A

2017-01-01

Objective: To test using the facial nerve as a reference for assessment of the cochlear nerve size in patients with acquired long-standing sensorineural hearing loss (SNHL) using MRI multiplanar reconstruction. Methods: The study was retrospectively performed on 86 patients. Group 1 (study group, n = 53) with bilateral long-standing SNHL. Group 2 (control group, n = 33) without hearing loss. The nerve size was measured by drawing a region of interest around the cross-sectional circumference of the nerve in multiplanar reconstruction images. Results: No significant correlation was noted between the cochlear nerve and facial nerve size, and the patient's age, gender and weight (p > 0.05). In Group 1, the mean ratio of the cochlear to facial nerve size was 0.99 ± 0.30 (range: 0.52–1.86) and 1.12 ± 0.35 (range: 0.34–2.3) for the right and left sides, respectively. In Group 2, it was 1.18 ± 0.23 (range: 0.78–1.71) and 1.25 ± 0.25 (range: 0.85–1.94) for the right and left sides, respectively. The cochlear nerve size was statistically (p = 0.0004) smaller in Group 1 than in Group 2. Conclusion: The cochlear nerve size and the cochlear to facial nerve size ratio are significantly smaller in patients with acquired long-standing SNHL. Advances in knowledge: The facial nerve can be used as a reference for assessment of the cochlear nerve in patients with acquired long-standing SNHL. PMID:28368665

Cochlear microphonic broad tuning curves

NASA Astrophysics Data System (ADS)

Ayat, Mohammad; Teal, Paul D.; Searchfield, Grant D.; Razali, Najwani

2015-12-01

It is known that the cochlear microphonic voltage exhibits much broader tuning than does the basilar membrane motion. The most commonly used explanation for this is that when an electrode is inserted at a particular point inside the scala media, the microphonic potentials of neighbouring hair cells have different phases, leading to cancelation at the electrodes location. In situ recording of functioning outer hair cells (OHCs) for investigating this hypothesis is exceptionally difficult. Therefore, to investigate the discrepancy between the tuning curves of the basilar membrane and those of the cochlear microphonic, and the effect of phase cancellation of adjacent hair cells on the broadness of the cochlear microphonic tuning curves, we use an electromechanical model of the cochlea to devise an experiment. We explore the effect of adjacent hair cells (i.e., longitudinal phase cancellation) on the broadness of the cochlear microphonic tuning curves in different locations. The results of the experiment indicate that active longitudinal coupling (i.e., coupling with active adjacent outer hair cells) only slightly changes the broadness of the CM tuning curves. The results also demonstrate that there is a π phase difference between the potentials produced by the hair bundle and the soma near the place associated with the characteristic frequency based on place-frequency maps (i.e., the best place). We suggest that the transversal phase cancellation (caused by the phase difference between the hair bundle and the soma) plays a far more important role than longitudinal phase cancellation in the broadness of the cochlear microphonic tuning curves. Moreover, by increasing the modelled longitudinal resistance resulting the cochlear microphonic curves exhibiting sharper tuning. The results of the simulations suggest that the passive network of the organ of Corti determines the phase difference between the hair bundle and soma, and hence determines the sharpness of the cochlear microphonic tuning curves.

The auditory nerve overlapped waveform (ANOW): A new objective measure of low-frequency hearing

NASA Astrophysics Data System (ADS)

Lichtenhan, Jeffery T.; Salt, Alec N.; Guinan, John J.

2015-12-01

One of the most pressing problems today in the mechanics of hearing is to understand the mechanical motions in the apical half of the cochlea. Almost all available measurements from the cochlear apex of basilar membrane or other organ-of-Corti transverse motion have been made from ears where the health, or sensitivity, in the apical half of the cochlea was not known. A key step in understanding the mechanics of the cochlear base was to trust mechanical measurements only when objective measures from auditory-nerve compound action potentials (CAPs) showed good preparation sensitivity. However, such traditional objective measures are not adequate monitors of cochlear health in the very low-frequency regions of the apex that are accessible for mechanical measurements. To address this problem, we developed the Auditory Nerve Overlapped Waveform (ANOW) that originates from auditory nerve output in the apex. When responses from the round window to alternating low-frequency tones are averaged, the cochlear microphonic is canceled and phase-locked neural firing interleaves in time (i.e., overlaps). The result is a waveform that oscillates at twice the probe frequency. We have demonstrated that this Auditory Nerve Overlapped Waveform - called ANOW - originates from auditory nerve fibers in the cochlear apex [8], relates well to single-auditory-nerve-fiber thresholds, and can provide an objective estimate of low-frequency sensitivity [7]. Our new experiments demonstrate that ANOW is a highly sensitive indicator of apical cochlear function. During four different manipulations to the scala media along the cochlear spiral, ANOW amplitude changed when either no, or only small, changes occurred in CAP thresholds. Overall, our results demonstrate that ANOW can be used to monitor cochlear sensitivity of low-frequency regions during experiments that make apical basilar membrane motion measurements.

Cochlear implantation in autistic children with profound sensorineural hearing loss.

PubMed

Lachowska, Magdalena; Pastuszka, Agnieszka; Łukaszewicz-Moszyńska, Zuzanna; Mikołajewska, Lidia; Niemczyk, Kazimierz

2016-11-19

Cochlear implants have become the method of choice for the treatment of severe-to-profound hearing loss in both children and adults. Its benefits are well documented in the pediatric and adult population. Also deaf children with additional needs, including autism, have been covered by this treatment. The aim of this study was to assess the benefits from cochlear implantation in deafened children with autism as the only additional disability. This study analyzes data of six children. The follow-up time was at least 43 months. The following data were analyzed: medical history, reaction to music and sound, Ling's six sounds test, onomatopoeic word test, reaction to spoken child's name, response to requests, questionnaire given to parents, sound processor fitting sessions and data. After cochlear implantation each child presented other communication skills. In some children, the symptoms of speech understanding were observed. No increased hyperactivity associated with daily use cochlear implant was observed. The study showed that in autistic children the perception is very important for a child's sense of security and makes contact with parents easier. Our study showed that oral communication is not likely to be a realistic goal in children with cochlear implants and autism. The implantation results showed benefits that varied among those children. The traditional methods of evaluating the results of cochlear implantation in children with autism are usually insufficient to fully assess the functional benefits. These benefits should be assessed in a more comprehensive manner taking into account the limitations of communication resulting from the essence of autism. It is important that we share knowledge about these complex children with cochlear implants. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Music training improves pitch perception in prelingually deafened children with cochlear implants.

PubMed

Chen, Joshua Kuang-Chao; Chuang, Ann Yi Chiun; McMahon, Catherine; Hsieh, Jen-Chuen; Tung, Tao-Hsin; Li, Lieber Po-Hung

2010-04-01

The comparatively poor music appreciation in patients with cochlear implants might be ascribed to an inadequate exposure to music; however, the effect of training on music perception in prelingually deafened children with cochlear implants remains unknown. This study aimed to investigate whether previous musical education improves pitch perception ability in these children. Twenty-seven children with congenital/prelingual deafness of profound degree were studied. Test stimuli consisted of 2 sequential piano tones, ranging from C (256 Hz) to B (495 Hz). Children were asked to identify the pitch relationship between the 2 tones (same, higher, or lower). Effects of musical training duration, pitch-interval size, current age, age of implantation, gender, and type of cochlear implant on accuracy of pitch perception were evaluated. The duration of musical training positively correlated with the correct rate of pitch perception. Pitch perception performance was better in children who had a cochlear implant and were older than 6 years than in those who were aged < or =6 years (ie, preschool). Effect of pitch-interval size was insignificant on pitch perception, and there was no correlation between pitch perception and the age of implantation, gender, or type of cochlear implant. Musical training seems to improve pitch perception ability in prelingually deafened children with a cochlear implant. Auditory plasticity might play an important role in such enhancement. This suggests that incorporation of a structured training program on music perception early in life and as part of the postoperative rehabilitation program for prelingually deafened children with cochlear implants would be beneficial. A longitudinal study is needed to show whether improvement of music performance in these children is measurable by use of auditory evoked potentials.

Auditory Speech Perception Development in Relation to Patient's Age with Cochlear Implant

PubMed Central

Ciscare, Grace Kelly Seixas; Mantello, Erika Barioni; Fortunato-Queiroz, Carla Aparecida Urzedo; Hyppolito, Miguel Angelo; Reis, Ana Cláudia Mirândola Barbosa dos

2017-01-01

Introduction  A cochlear implant in adolescent patients with pre-lingual deafness is still a debatable issue. Objective  The objective of this study is to analyze and compare the development of auditory speech perception in children with pre-lingual auditory impairment submitted to cochlear implant, in different age groups in the first year after implantation. Method  This is a retrospective study, documentary research, in which we analyzed 78 reports of children with severe bilateral sensorineural hearing loss, unilateral cochlear implant users of both sexes. They were divided into three groups: G1, 22 infants aged less than 42 months; G2, 28 infants aged between 43 to 83 months; and G3, 28 older than 84 months. We collected medical record data to characterize the patients, auditory thresholds with cochlear implants, assessment of speech perception, and auditory skills. Results  There was no statistical difference in the association of the results among groups G1, G2, and G3 with sex, caregiver education level, city of residence, and speech perception level. There was a moderate correlation between age and hearing aid use time, age and cochlear implants use time. There was a strong correlation between age and the age cochlear implants was performed, hearing aid use time and age CI was performed. Conclusion  There was no statistical difference in the speech perception in relation to the patient's age when cochlear implant was performed. There were statistically significant differences for the variables of auditory deprivation time between G3 - G1 and G2 - G1 and hearing aid use time between G3 - G2 and G3 - G1. PMID:28680487

Auditory Mechanics of the Tectorial Membrane and the Cochlear Spiral

PubMed Central

Gavara, Núria; Manoussaki, Daphne; Chadwick, Richard S.

2012-01-01

Purpose of review This review is timely and relevant since new experimental and theoretical findings suggest that cochlear mechanics from the nanoscale to the macroscale are affected by mechanical properties of the tectorial membrane and the spiral shape. Recent findings Main tectorial membrane themes covered are i) composition and morphology, ii) nanoscale mechanical interactions with the outer hair cell bundle, iii) macroscale longitudinal coupling, iv) fluid interaction with inner hair cell bundles, v) macroscale dynamics and waves. Main cochlear spiral themes are macroscale low-frequency energy focusing and microscale organ of Corti shear gain. Implications Findings from new experimental and theoretical models reveal exquisite sensitivity of cochlear mechanical performance to tectorial membrane structural organization, mechanics, and its positioning with respect to hair bundles. The cochlear spiral geometry is a major determinant of low frequency hearing. Suggestions are made for future research directions. PMID:21785353

[Pre-operation evaluation and intra-operation management of cochlear implantation].

PubMed

Zhang, Dao-xing; Hu, Bao-hua; Xiao, Yu-li; Shi, Bo-ning

2004-10-01

To summarize pre-operation evaluation experiences in cochlear implantation. Performing auditory evaluation and image analysis seriously in 158 severe hearing loss or total deaf cases before cochlear implantation, comparing their performance with the findings during and post operation. Among the total 158 cases, 116 cases with normal structure, 42 cases with the abnormal findings of the inner or middle ear. Stapedial gusher happened in 6 cases, 1 case was not predicted before operation. Except 1 case with serious malformation, the findings of other 157 cases in operation were consistent with the pre-operation evaluation. We helped all patients reconstruct auditory conduction with cochlear implantation, and the average hearing level up to 37.6 dB SPL. Performing image analysis seriously before operation and planning for operation according to HRCT can do great help to cochlear implantation. The operation under the HRCT instruction has less complications.

[Topographic anatomy of the hook region and its significance for the choice of the surgical technique for the cochlear implantation].

PubMed

Yanov, Yu K; Kuzovkov, V E; Lilenko, A S; Kostevich, I V; Sugarova, S B; Amonov, A Sh

The mode of the introduction of the active electrode of a cochlear implant into the cochlea remains a key issue as far as cochlear implantation is concerned. Especially much attention has recently been given to the relationship between the anatomical features of the basal region of the cochlea (the so-called 'fish hook') and the possibility to approach it. We have undertaken the attempt to optimize the approach to the tympanic canal (scala tympanica) of the cochlea with a view to reducing to a minimum the risk of an injury to the cochlear structures in the course of cochlear implantation. A total of 35 cadaveric temporal bones were examined to measure the fine structures of the hook region and evaluate the risk of their damages associated with various approaches to the tympanic canal.

Congenitally deafblind children and cochlear implants: effects on communication.

PubMed

Dammeyer, Jesper

2009-01-01

There has been much research conducted demonstrating the positive benefits of cochlear implantation (CI) in children who are deaf. Research on CI in children who are both deaf and blind, however, is lacking. The purpose of this article is to present a study of five congenitally deafblind children who received cochlear implants between 2.2 and 4.2 years of age. Ratings of video observations were used to measure the children's early communication development with and without the use of their cochlear implants. In addition, parental interviews were used to assess the benefits parents perceived regarding their children's cochlear implants. Two examples are included in this article to illustrate the parents' perspectives about CI in their deafblind children. Benefits of CI in this cohort of children included improved attention and emotional response as well as greater use of objects in interaction with adults. The best overall outcome of CI is not spoken language but better communication.

Deep brain stimulation with a pre-existing cochlear implant: Surgical technique and outcome.

PubMed

Eddelman, Daniel; Wewel, Joshua; Wiet, R Mark; Metman, Leo V; Sani, Sepehr

2017-01-01

Patients with previously implanted cranial devices pose a special challenge in deep brain stimulation (DBS) surgery. We report the implantation of bilateral DBS leads in a patient with a cochlear implant. Technical nuances and long-term interdevice functionality are presented. A 70-year-old patient with advancing Parkinson's disease and a previously placed cochlear implant for sensorineural hearing loss was referred for placement of bilateral DBS in the subthalamic nucleus (STN). Prior to DBS, the patient underwent surgical removal of the subgaleal cochlear magnet, followed by stereotactic MRI, frame placement, stereotactic computed tomography (CT), and merging of imaging studies. This technique allowed for successful computational merging, MRI-guided targeting, and lead implantation with acceptable accuracy. Formal testing and programming of both the devices were successful without electrical interference. Successful DBS implantation with high resolution MRI-guided targeting is technically feasible in patients with previously implanted cochlear implants by following proper precautions.

Disorders of cochlear blood flow.

PubMed

Nakashima, Tsutomu; Naganawa, Shinji; Sone, Michihiko; Tominaga, Mitsuo; Hayashi, Hideo; Yamamoto, Hiroshi; Liu, Xiuli; Nuttall, Alfred L

2003-09-01

The cochlea is principally supplied from the inner ear artery (labyrinthine artery), which is usually a branch of the anterior inferior cerebellar artery. Cochlear blood flow is a function of cochlear perfusion pressure, which is calculated as the difference between mean arterial blood pressure and inner ear fluid pressure. Many otologic disorders such as noise-induced hearing loss, endolymphatic hydrops and presbycusis are suspected of being related to alterations in cochlear blood flow. However, the human cochlea is not easily accessible for investigation because this delicate sensory organ is hidden deep in the temporal bone. In patients with sensorineural hearing loss, magnetic resonance imaging, laser-Doppler flowmetry and ultrasonography have been used to investigate the status of cochlear blood flow. There have been many reports of hearing loss that were considered to be caused by blood flow disturbance in the cochlea. However, direct evidence of blood flow disturbance in the cochlea is still lacking in most of the cases.

Music Perception with Cochlear Implants: A Review

PubMed Central

McDermott, Hugh J.

2004-01-01

The acceptance of cochlear implantation as an effective and safe treatment for deafness has increased steadily over the past quarter century. The earliest devices were the first implanted prostheses found to be successful in compensating partially for lost sensory function by direct electrical stimulation of nerves. Initially, the main intention was to provide limited auditory sensations to people with profound or total sensorineural hearing impairment in both ears. Although the first cochlear implants aimed to provide patients with little more than awareness of environmental sounds and some cues to assist visual speech-reading, the technology has advanced rapidly. Currently, most people with modern cochlear implant systems can understand speech using the device alone, at least in favorable listening conditions. In recent years, an increasing research effort has been directed towards implant users’ perception of nonspeech sounds, especially music. This paper reviews that research, discusses the published experimental results in terms of both psychophysical observations and device function, and concludes with some practical suggestions about how perception of music might be enhanced for implant recipients in the future. The most significant findings of past research are: (1) On average, implant users perceive rhythm about as well as listeners with normal hearing; (2) Even with technically sophisticated multiple-channel sound processors, recognition of melodies, especially without rhythmic or verbal cues, is poor, with performance at little better than chance levels for many implant users; (3) Perception of timbre, which is usually evaluated by experimental procedures that require subjects to identify musical instrument sounds, is generally unsatisfactory; (4) Implant users tend to rate the quality of musical sounds as less pleasant than listeners with normal hearing; (5) Auditory training programs that have been devised specifically to provide implant users with structured musical listening experience may improve the subjective acceptability of music that is heard through a prosthesis; (6) Pitch perception might be improved by designing innovative sound processors that use both temporal and spatial patterns of electric stimulation more effectively and precisely to overcome the inherent limitations of signal coding in existing implant systems; (7) For the growing population of implant recipients who have usable acoustic hearing, at least for low-frequency sounds, perception of music is likely to be much better with combined acoustic and electric stimulation than is typical for deaf people who rely solely on the hearing provided by their prostheses. PMID:15497033

Music perception with cochlear implants: a review.

PubMed

McDermott, Hugh J

2004-01-01

The acceptance of cochlear implantation as an effective and safe treatment for deafness has increased steadily over the past quarter century. The earliest devices were the first implanted prostheses found to be successful in compensating partially for lost sensory function by direct electrical stimulation of nerves. Initially, the main intention was to provide limited auditory sensations to people with profound or total sensorineural hearing impairment in both ears. Although the first cochlear implants aimed to provide patients with little more than awareness of environmental sounds and some cues to assist visual speech-reading, the technology has advanced rapidly. Currently, most people with modern cochlear implant systems can understand speech using the device alone, at least in favorable listening conditions. In recent years, an increasing research effort has been directed towards implant users' perception of nonspeech sounds, especially music. This paper reviews that research, discusses the published experimental results in terms of both psychophysical observations and device function, and concludes with some practical suggestions about how perception of music might be enhanced for implant recipients in the future. The most significant findings of past research are: (1) On average, implant users perceive rhythm about as well as listeners with normal hearing; (2) Even with technically sophisticated multiple-channel sound processors, recognition of melodies, especially without rhythmic or verbal cues, is poor, with performance at little better than chance levels for many implant users; (3) Perception of timbre, which is usually evaluated by experimental procedures that require subjects to identify musical instrument sounds, is generally unsatisfactory; (4) Implant users tend to rate the quality of musical sounds as less pleasant than listeners with normal hearing; (5) Auditory training programs that have been devised specifically to provide implant users with structured musical listening experience may improve the subjective acceptability of music that is heard through a prosthesis; (6) Pitch perception might be improved by designing innovative sound processors that use both temporal and spatial patterns of electric stimulation more effectively and precisely to overcome the inherent limitations of signal coding in existing implant systems; (7) For the growing population of implant recipients who have usable acoustic hearing, at least for low-frequency sounds, perception of music is likely to be much better with combined acoustic and electric stimulation than is typical for deaf people who rely solely on the hearing provided by their prostheses.

Imaging Electrically Evoked Micromechanical Motion within the Organ of Corti of the Excised Gerbil Cochlea

PubMed Central

Karavitaki, K. Domenica; Mountain, David C.

2007-01-01

The outer hair cell (OHC) of the mammalian inner ear exhibits an unusual form of somatic motility that can follow membrane-potential changes at acoustic frequencies. The cellular forces that produce this motility are believed to amplify the motion of the cochlear partition, thereby playing a key role in increasing hearing sensitivity. To better understand the role of OHC somatic motility in cochlear micromechanics, we developed an excised cochlea preparation to visualize simultaneously the electrically-evoked motion of hundreds of cells within the organ of Corti (OC). The motion was captured using stroboscopic video microscopy and quantified using cross-correlation techniques. The OC motion at ∼2–6 octaves below the characteristic frequency of the region was complex: OHC, Deiter's cell, and Hensen's cell motion were hundreds of times larger than the tectorial membrane, reticular lamina (RL), and pillar cell motion; the inner rows of OHCs moved antiphasic to the outer row; OHCs pivoted about the RL; and Hensen's cells followed the motion of the outer row of OHCs. Our results suggest that the effective stimulus to the inner hair cell hair bundles results not from a simple OC lever action, as assumed by classical models, but by a complex internal motion coupled to the RL. PMID:17277194

Word segmentation in phonemically identical and prosodically different sequences using cochlear implants: A case study.

PubMed

Basirat, Anahita

2017-01-01

Cochlear implant (CI) users frequently achieve good speech understanding based on phoneme and word recognition. However, there is a significant variability between CI users in processing prosody. The aim of this study was to examine the abilities of an excellent CI user to segment continuous speech using intonational cues. A post-lingually deafened adult CI user and 22 normal hearing (NH) subjects segmented phonemically identical and prosodically different sequences in French such as 'l'affiche' (the poster) versus 'la fiche' (the sheet), both [lafiʃ]. All participants also completed a minimal pair discrimination task. Stimuli were presented in auditory-only and audiovisual presentation modalities. The performance of the CI user in the minimal pair discrimination task was 97% in the auditory-only and 100% in the audiovisual condition. In the segmentation task, contrary to the NH participants, the performance of the CI user did not differ from the chance level. Visual speech did not improve word segmentation. This result suggests that word segmentation based on intonational cues is challenging when using CIs even when phoneme/word recognition is very well rehabilitated. This finding points to the importance of the assessment of CI users' skills in prosody processing and the need for specific interventions focusing on this aspect of speech communication.

Indication criteria for cochlear implants and hearing aids: impact of audiological and non-audiological findings

PubMed Central

Haumann, Sabine; Hohmann, Volker; Meis, Markus; Herzke, Tobias; Lenarz, Thomas; Büchner, Andreas

2012-01-01

Owing to technological progress and a growing body of clinical experience, indication criteria for cochlear implants (CI) are being extended to less severe hearing impairments. It is, therefore, worth reconsidering these indication criteria by introducing novel testing procedures. The diagnostic evidence collected will be evaluated. The investigation includes postlingually deafened adults seeking a CI. Prior to surgery, speech perception tests [Freiburg Speech Test and Oldenburg sentence (OLSA) test] were performed unaided and aided using the Oldenburg Master Hearing Aid (MHA) system. Linguistic skills were assessed with the visual Text Reception Threshold (TRT) test, and general state of health, socio-economic status (SES) and subjective hearing were evaluated through questionnaires. After surgery, the speech tests were repeated aided with a CI. To date, 97 complete data sets are available for evaluation. Statistical analyses showed significant correlations between postsurgical speech reception threshold (SRT) measured with the adaptive OLSA test and pre-surgical data such as the TRT test (r=−0.29), SES (r=−0.22) and (if available) aided SRT (r=0.53). The results suggest that new measures and setups such as the TRT test, SES and speech perception with the MHA provide valuable extra information regarding indication for CI. PMID:26557327

Monaural Congenital Deafness Affects Aural Dominance and Degrades Binaural Processing

PubMed Central

Tillein, Jochen; Hubka, Peter; Kral, Andrej

2016-01-01

Cortical development extensively depends on sensory experience. Effects of congenital monaural and binaural deafness on cortical aural dominance and representation of binaural cues were investigated in the present study. We used an animal model that precisely mimics the clinical scenario of unilateral cochlear implantation in an individual with single-sided congenital deafness. Multiunit responses in cortical field A1 to cochlear implant stimulation were studied in normal-hearing cats, bilaterally congenitally deaf cats (CDCs), and unilaterally deaf cats (uCDCs). Binaural deafness reduced cortical responsiveness and decreased response thresholds and dynamic range. In contrast to CDCs, in uCDCs, cortical responsiveness was not reduced, but hemispheric-specific reorganization of aural dominance and binaural interactions were observed. Deafness led to a substantial drop in binaural facilitation in CDCs and uCDCs, demonstrating the inevitable role of experience for a binaural benefit. Sensitivity to interaural time differences was more reduced in uCDCs than in CDCs, particularly at the hemisphere ipsilateral to the hearing ear. Compared with binaural deafness, unilateral hearing prevented nonspecific reduction in cortical responsiveness, but extensively reorganized aural dominance and binaural responses. The deaf ear remained coupled with the cortex in uCDCs, demonstrating a significant difference to deprivation amblyopia in the visual system. PMID:26803166

Monaural Congenital Deafness Affects Aural Dominance and Degrades Binaural Processing.

PubMed

Tillein, Jochen; Hubka, Peter; Kral, Andrej

2016-04-01

Cortical development extensively depends on sensory experience. Effects of congenital monaural and binaural deafness on cortical aural dominance and representation of binaural cues were investigated in the present study. We used an animal model that precisely mimics the clinical scenario of unilateral cochlear implantation in an individual with single-sided congenital deafness. Multiunit responses in cortical field A1 to cochlear implant stimulation were studied in normal-hearing cats, bilaterally congenitally deaf cats (CDCs), and unilaterally deaf cats (uCDCs). Binaural deafness reduced cortical responsiveness and decreased response thresholds and dynamic range. In contrast to CDCs, in uCDCs, cortical responsiveness was not reduced, but hemispheric-specific reorganization of aural dominance and binaural interactions were observed. Deafness led to a substantial drop in binaural facilitation in CDCs and uCDCs, demonstrating the inevitable role of experience for a binaural benefit. Sensitivity to interaural time differences was more reduced in uCDCs than in CDCs, particularly at the hemisphere ipsilateral to the hearing ear. Compared with binaural deafness, unilateral hearing prevented nonspecific reduction in cortical responsiveness, but extensively reorganized aural dominance and binaural responses. The deaf ear remained coupled with the cortex in uCDCs, demonstrating a significant difference to deprivation amblyopia in the visual system. © The Author 2016. Published by Oxford University Press.

Language, Mental State Vocabulary, and False Belief Understanding in Children with Cochlear Implants

ERIC Educational Resources Information Center

Peters, Kimberly; Remmel, Ethan; Richards, Debra

2009-01-01

Purpose: This study examined false belief understanding and its predictors in school-age children who are deaf with cochlear implants and who use spoken language. Method: False belief understanding was measured through an explanation-of-action task in 30 children between the ages of 3 and 12 years who used cochlear implants. Children told a…

Cyborgization: Deaf Education for Young Children in the Cochlear Implantation Era

ERIC Educational Resources Information Center

Valente, Joseph Michael

2011-01-01

The author, who was raised oral deaf himself, recounts a visit to a school for young deaf children and discovers that young d/Deaf children and their rights are subverted by the cochlear implantation empire. The hypercapitalist, techno-manic times of cochlear implantation has wreaked havoc to the lives of not only young children with deafness but…

Cochlear Implants. National Institutes of Health Consensus Development Conference Statement (May 4, 1988). Volume 7, Number 2.

ERIC Educational Resources Information Center

National Institutes of Health (DHHS), Bethesda, MD.

This paper reports the results of a Consensus Development Conference on Cochlear Implants sponsored by the National Institutes of Health to improve the hearing of children and adults with hearing impairments. The following questions are addressed: (1) Who is a suitable candidate for a cochlear implant? (2) What are the advantages and disadvantages…

Auditory Environment across the Life Span of Cochlear Implant Users: Insights from Data Logging

ERIC Educational Resources Information Center

Busch, Tobias; Vanpoucke, Filiep; van Wieringen, Astrid

2017-01-01

Purpose: We describe the natural auditory environment of people with cochlear implants (CIs), how it changes across the life span, and how it varies between individuals. Method: We performed a retrospective cross-sectional analysis of Cochlear Nucleus 6 CI sound-processor data logs. The logs were obtained from 1,501 people with CIs (ages 0-96…

Congenitally Deafblind Children and Cochlear Implants: Effects on Communication

ERIC Educational Resources Information Center

Dammeyer, Jesper

2009-01-01

There has been much research conducted demonstrating the positive benefits of cochlear implantation (CI) in children who are deaf. Research on CI in children who are both deaf and blind, however, is lacking. The purpose of this article is to present a study of five congenitally deafblind children who received cochlear implants between 2.2 and 4.2…

Searching for Cochlear Implant Information on the Internet Maze: Implications for Parents and Professionals

ERIC Educational Resources Information Center

Zaidman-Zait, Anat; Jamieson, Janet R.

2004-01-01

The present study has three purposes: (a) to determine who disseminates information on cochlear implants on the Web; (b) to describe a representative sample of Web sites that disseminate information on cochlear implants, with a focus on the content topics and their relevance to parents of deaf children; and (c) to discuss the practical issues of…

Benefit of Wearing a Hearing Aid on the Unimplanted Ear in Adult Users of a Cochlear Implant

ERIC Educational Resources Information Center

Dunn, Camille C.; Tyler, Richard S.; Witt, Shelley A.

2005-01-01

The purpose of this investigation was to document performance of participants wearing a cochlear implant and hearing aid in opposite ears on speech-perception and localization tests. Twelve individuals who wore a cochlear implant and a hearing aid on contralateral ears were tested on their abilities to understand words in quiet and sentences in…

A Longitudinal Study in Children with Sequential Bilateral Cochlear Implants: Time Course for the Second Implanted Ear and Bilateral Performance

ERIC Educational Resources Information Center

Reeder, Ruth M.; Firszt, Jill B.; Cadieux, Jamie H.; Strube, Michael J.

2017-01-01

Purpose: Whether, and if so when, a second-ear cochlear implant should be provided to older, unilaterally implanted children is an ongoing clinical question. This study evaluated rate of speech recognition progress for the second implanted ear and with bilateral cochlear implants in older sequentially implanted children and evaluated localization…

Educational Interpreters: Meeting the Communication Needs of Children with Cochlear Implants

ERIC Educational Resources Information Center

Melton, Julie; Higbee, Renee

2013-01-01

Since the early 1990s, when the U.S. Food and Drug Administration approved cochlear implants for deaf and hard of hearing children, the number of children who have cochlear implants has increased in mainstream settings. Recent research suggests that these students, like their deaf and hard of hearing peers without implants who use sign language,…

Prevention and management of cochlear implant infections.

PubMed

Gluth, Michael B; Singh, Rajesh; Atlas, Marcus D

2011-11-01

Understanding the issues of infection related to an implantable medical device is crucial to all cochlear implant teams. Furthermore, given the risk of central nervous system complications and the relatively high quantity of underlying resource investment associated with cochlear implantation, the stakes of infection are high. The optimal strategies to prevent and manage such infections are still evolving as good-quality prospective data to guide such management decisions are not yet abundant within the medical literature and many recommendations are based on retrospective reviews or anecdotal evidence. We will outline a general strategy to deal with cochlear implant-related infection based on both the authors' experience and the published literature.

Development of a phase-sensitive Fourier domain optical coherence tomography system to measure mouse organ of Corti vibrations in two cochlear turns

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramamoorthy, Sripriya; Zhang, Yuan; Jacques, Steven

In this study, we have developed a phase-sensitive Fourier-domain optical coherence tomography system to simultaneously measure the in vivo inner ear vibrations in the hook area and second turn of the mouse cochlea. This technical development will enable measurement of intra-cochlear distortion products at ideal locations such as the distortion product generation site and reflection site. This information is necessary to un-mix the complex mixture of intra-cochlear waves comprising the DPOAE and thus leads to the non-invasive identification of the local region of cochlear damage.

Use of Neural Response Telemetry for Pediatric Cochlear Implants: Current Practice.

PubMed

Almosnino, Galit; Anne, Samantha; Schwartz, Seth R

2018-06-01

Evaluate usage trends of neural response telemetry (NRT) in cochlear implant centers across the nation and assess reported benefits of intraoperative NRT for pediatric cochlear implant recipients. Survey. All US cochlear implant centers (n = 110). A 15-question multiple-choice survey was distributed electronically to all centers. The survey captured demographic information of all centers, practice patterns surrounding the use of NRT, and the extent to which intraoperative NRT is of benefit. Thirty-two invited participants (29%) completed the survey. A majority of participants reported practicing in an academic center (66%), followed by a hospital setting (19%) and private practice (16%). Seventy-two percent of survey participants reported using NRT for pediatric cochlear implant recipients. Sixty-three percent felt it improved the ability to program at initial activation, and 50% of participants felt that NRT improves satisfaction at initial activation. This study suggests that a majority of surgeons use intraoperative NRT for pediatric cochlear implantation as an additional measure to ensure appropriate electrode placement and improve device activation. Larger studies are needed to better establish the relationship between intraoperative NRT and postoperative outcomes and justify the additional costs associated with intraoperative NRT.

Topics in Modeling of Cochlear Dynamics: Computation, Response and Stability Analysis

NASA Astrophysics Data System (ADS)

Filo, Maurice G.

This thesis touches upon several topics in cochlear modeling. Throughout the literature, mathematical models of the cochlea vary according to the degree of biological realism to be incorporated. This thesis casts the cochlear model as a continuous space-time dynamical system using operator language. This framework encompasses a wider class of cochlear models and makes the dynamics more transparent and easier to analyze before applying any numerical method to discretize space. In fact, several numerical methods are investigated to study the computational efficiency of the finite dimensional realizations in space. Furthermore, we study the effects of the active gain perturbations on the stability of the linearized dynamics. The stability analysis is used to explain possible mechanisms underlying spontaneous otoacoustic emissions and tinnitus. Dynamic Mode Decomposition (DMD) is introduced as a useful tool to analyze the response of nonlinear cochlear models. Cochlear response features are illustrated using DMD which has the advantage of explicitly revealing the spatial modes of vibrations occurring in the Basilar Membrane (BM). Finally, we address the dynamic estimation problem of BM vibrations using Extended Kalman Filters (EKF). Due to the limitations of noninvasive sensing schemes, such algorithms are inevitable to estimate the dynamic behavior of a living cochlea.

Voice gender identification by cochlear implant users: The role of spectral and temporal resolution

NASA Astrophysics Data System (ADS)

Fu, Qian-Jie; Chinchilla, Sherol; Nogaki, Geraldine; Galvin, John J.

2005-09-01

The present study explored the relative contributions of spectral and temporal information to voice gender identification by cochlear implant users and normal-hearing subjects. Cochlear implant listeners were tested using their everyday speech processors, while normal-hearing subjects were tested under speech processing conditions that simulated various degrees of spectral resolution, temporal resolution, and spectral mismatch. Voice gender identification was tested for two talker sets. In Talker Set 1, the mean fundamental frequency values of the male and female talkers differed by 100 Hz while in Talker Set 2, the mean values differed by 10 Hz. Cochlear implant listeners achieved higher levels of performance with Talker Set 1, while performance was significantly reduced for Talker Set 2. For normal-hearing listeners, performance was significantly affected by the spectral resolution, for both Talker Sets. With matched speech, temporal cues contributed to voice gender identification only for Talker Set 1 while spectral mismatch significantly reduced performance for both Talker Sets. The performance of cochlear implant listeners was similar to that of normal-hearing subjects listening to 4-8 spectral channels. The results suggest that, because of the reduced spectral resolution, cochlear implant patients may attend strongly to periodicity cues to distinguish voice gender.

Verbal Working Memory in Children With Cochlear Implants

PubMed Central

Caldwell-Tarr, Amanda; Low, Keri E.; Lowenstein, Joanna H.

2017-01-01

Purpose Verbal working memory in children with cochlear implants and children with normal hearing was examined. Participants Ninety-three fourth graders (47 with normal hearing, 46 with cochlear implants) participated, all of whom were in a longitudinal study and had working memory assessed 2 years earlier. Method A dual-component model of working memory was adopted, and a serial recall task measured storage and processing. Potential predictor variables were phonological awareness, vocabulary knowledge, nonverbal IQ, and several treatment variables. Potential dependent functions were literacy, expressive language, and speech-in-noise recognition. Results Children with cochlear implants showed deficits in storage and processing, similar in size to those at second grade. Predictors of verbal working memory differed across groups: Phonological awareness explained the most variance in children with normal hearing; vocabulary explained the most variance in children with cochlear implants. Treatment variables explained little of the variance. Where potentially dependent functions were concerned, verbal working memory accounted for little variance once the variance explained by other predictors was removed. Conclusions The verbal working memory deficits of children with cochlear implants arise due to signal degradation, which limits their abilities to acquire phonological awareness. That hinders their abilities to store items using a phonological code. PMID:29075747

Social participation of children and adolescents with cochlear implants: a qualitative analysis of parent, teacher, and child interviews.

PubMed

Punch, Renée; Hyde, Merv

2011-01-01

Psychosocial factors, including socioemotional well-being, peer relationships, and social inclusion with hearing and deaf peers, are increasingly becoming a focus of research investigating children with cochlear implants. The study reported here extends the largely quantitative findings of previous research through a qualitative analysis of interviews with parents, teachers, and pediatric cochlear implant users themselves in three eastern states of Australia. We interviewed 24 parents, 15 teachers, and 11 children and adolescents. The findings displayed commonalities across the three groups of participants, indicating positive experiences around the children's psychosocial development with their cochlear implants, but also ongoing difficulties communicating in groups of people and problems related to social skills. Some children had little contact with other deaf children (with or without cochlear implants) despite parents and teachers perceiving such contact beneficial. Children attending schools where there were other deaf children valued friendships with both deaf and hearing peers. Adolescence was a particularly difficult time for some as they struggled with feelings of self-consciousness about their deafness and external cochlear implant equipment and worries around friendships, dating, and their future place in the world. Recommendations for practice and further research are made.

Auditory Speech Perception Tests in Relation to the Coding Strategy in Cochlear Implant.

PubMed

Bazon, Aline Cristine; Mantello, Erika Barioni; Gonçales, Alina Sanches; Isaac, Myriam de Lima; Hyppolito, Miguel Angelo; Reis, Ana Cláudia Mirândola Barbosa

2016-07-01

The objective of the evaluation of auditory perception of cochlear implant users is to determine how the acoustic signal is processed, leading to the recognition and understanding of sound. To investigate the differences in the process of auditory speech perception in individuals with postlingual hearing loss wearing a cochlear implant, using two different speech coding strategies, and to analyze speech perception and handicap perception in relation to the strategy used. This study is prospective cross-sectional cohort study of a descriptive character. We selected ten cochlear implant users that were characterized by hearing threshold by the application of speech perception tests and of the Hearing Handicap Inventory for Adults. There was no significant difference when comparing the variables subject age, age at acquisition of hearing loss, etiology, time of hearing deprivation, time of cochlear implant use and mean hearing threshold with the cochlear implant with the shift in speech coding strategy. There was no relationship between lack of handicap perception and improvement in speech perception in both speech coding strategies used. There was no significant difference between the strategies evaluated and no relation was observed between them and the variables studied.

Effects of a Word-Learning Training on Children With Cochlear Implants

PubMed Central

Lund, Emily

2014-01-01

Preschool children with hearing loss who use cochlear implants demonstrate vocabulary delays when compared to their peers without hearing loss. These delays may be a result of deficient word-learning abilities; children with cochlear implants perform more poorly on rapid word-learning tasks than children with normal hearing. This study explored the malleability of rapid word learning of preschoolers with cochlear implants by evaluating the effects of a word-learning training on rapid word learning. A single-subject, multiple probe design across participants measured the impact of the training on children’s rapid word-learning performance. Participants included 5 preschool children with cochlear implants who had an expressive lexicon of less than 150 words. An investigator guided children to identify, repeat, and learn about unknown sets of words in 2-weekly sessions across 10 weeks. The probe measure, a rapid word-learning task with a different set of words than those taught during training, was collected in the baseline, training, and maintenance conditions. All participants improved their receptive rapid word-learning performance in the training condition. The functional relation indicates that the receptive rapid word-learning performance of children with cochlear implants is malleable. PMID:23981321

The cochlear implant as a tinnitus treatment.

PubMed

Vallés-Varela, Héctor; Royo-López, Juan; Carmen-Sampériz, Luis; Sebastián-Cortés, José M; Alfonso-Collado, Ignacio

2013-01-01

Tinnitus is a symptom of high prevalence in patients with cochlear pathology. We studied the evolution of tinnitus in patients undergoing unilateral cochlear implantation for treatment of profound hearing loss. This was a longitudinal, retrospective study of patients that underwent unilateral cochlear implantation and who had bilateral tinnitus. Tinnitus was assessed quantitatively and qualitatively before surgery and at 6 and 12 months after surgery. We evaluated 20 patients that underwent unilateral cochlear implantation with a Nucleus(®) CI24RE Contour Advance™ electrode device. During the periods in which the device was in operation, improvement or disappearance of tinnitus was evidenced in the ipsilateral ear in 65% of patients, and in the contralateral ear, in 50%. In periods in which the device was disconnected, improvement or disappearance of tinnitus was found in the ipsilateral ear in 50% of patients, and in the ear contralateral to the implant in 45% of the patients. In 10% of the patients, a new tinnitus appeared in the ipsilateral ear. The patients with profound hearing loss and bilateral tinnitus treated with unilateral cochlear implantation improved in a high percentage of cases, in the ipsilateral ear and in the contralateral ear. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Clinical outcomes of scala vestibuli cochlear implantation in children with partial labyrinthine ossification.

PubMed

Lin, Yung-Song

2009-03-01

Cochlear implantation via the scala vestibuli is a viable approach in those with ossification in the scala tympani. With extended cochlear implant experience, there is no significant difference in the mapping parameters and auditory performance between those implanted via scala vestibuli and via scala tympani. To assess the clinical outcomes of cochlear implantation via scala vestibuli. In a cohort follow-up study, 11 prelingually deafened children who received cochlear implantation between age 3 and 10 years through the scala vestibuli served as participants. The mapping parameters (i.e. comfortable level (C), threshold level (T), dynamic range) and auditory performance of each participant were evaluated following initial cochlear implant stimulation, then at 3 month intervals for 2 years, then semi-annually. The follow-up period lasted for 9 years 9 months on average, with a minimum of 8 years 3 months. The clinical results of the mapping parameters and auditory performance of children implanted via the scala vestibuli were comparative to those who were implanted via the scala tympani. No balance problem was reported by any of these patients. One child exhibited residual low frequency hearing after implantation.

Current Research with Cochlear Implants at Arizona State University

PubMed Central

Dorman, Michael F.; Spahr, Anthony; Gifford, Rene H.; Cook, Sarah; Zhang, Ting; Loiselle, Louise; Yost, William; Cardy, Lara; Whittingham, JoAnne; Schramm, David

2013-01-01

In this article we review, and discuss the clinical implications of, five projects currently underway in the Cochlear Implant Laboratory at Arizona State University. The projects are (1) norming the AzBio sentence test, (2) comparing the performance of bilateral and bimodal cochlear implant (CI) patients in realistic listening environments, (3) accounting for the benefit provided to bimodal patients by low-frequency acoustic stimulation, (4) assessing localization by bilateral hearing aid patients and the implications of that work for hearing preservation patients, and (5) studying heart rate variability as a possible measure for quantifying the stress of listening via an implant. The long-term goals of the laboratory are to improve the performance of patients fit with cochlear implants and to understand the mechanisms, physiological or electronic, that underlie changes in performance. We began our work with cochlear implant patients in the mid-1980s and received our first grant from the National Institutes of Health (NIH) for work with implanted patients in 1989. Since that date our work with cochlear implant patients has been funded continuously by the NIH. In this report we describe some of the research currently being conducted in our laboratory. PMID:22668760

The importance of electrically evoked stapedial reflex in cochlear implant.

PubMed

Andrade, Kelly Cristina Lira de; Leal, Mariana de Carvalho; Muniz, Lilian Ferreira; Menezes, Pedro de Lemos; Albuquerque, Katia Maria Gomes de; Carnaúba, Aline Tenório Lins

2014-01-01

The most important stage in fitting a cochlear implant is the identification of its dynamic range. The use of objective measures, in particular the electrically elicited stapedius reflex, may provide suitable assistence for initial fitting of cochlear implant, especially in children or adult with multiple disorders, because they provide specific values that serve as the basis of early cochlear implant programming. Verify through a review the use of the electrically elicited stapedius reflex threshold during the activation and mapping process of cochlear implant. Bibliographical search on the Pubmed and Bireme plataforms, and also on Medline, LILACS and SciELO databases, with standard searches until September 2012, using specific keywords. For the selection and evaluation of scientific studies found in the search, criterias have been established, considering the following aspects: author, year/location, grade of recommendation/level of evidence, purpose, sample, age, mean age in years, evaluative testing, results and conclusion. Among 7,304 articles found, 7,080 were excluded from the title, 152 from the abstract, 17 from the article reading, 43 were repeated and 12 were selected for the study. The electrically elicited stapedius reflex may support when programming the cochlear implant, especially in patients with inconsistent responses.

The relationship between loudness intensity functions and the click-ABR wave V latency.

PubMed

Serpanos, Y C; O'Malley, H; Gravel, J S

1997-10-01

To assess the relationship of loudness growth and the click-evoked auditory brain stem response (ABR) wave V latency-intensity function (LIF) in listeners with normal hearing or cochlear hearing loss. The effect of hearing loss configuration on the intensity functions was also examined. Behavioral and electrophysiological intensity functions were obtained using click stimuli of comparable intensities in listeners with normal hearing (Group I; n = 10), and cochlear hearing loss of flat (Group II; n = 10) or sloping (Group III; n = 10) configurations. Individual intensity functions were obtained from measures of loudness growth using the psychophysical methods of absolute magnitude estimation and production of loudness (geometrically averaged to provide the measured loudness function), and from the wave V latency measures of the ABR. Slope analyses for the behavioral and electrophysiological intensity functions were separately performed by group. The loudness growth functions for the groups with cochlear hearing loss approximated the normal function at high intensities, with overall slope values consistent with those reported from previous psychophysical research. The ABR wave V LIF for the group with a flat configuration of cochlear hearing loss approximated the normal function at high intensities, and was displaced parallel to the normal function for the group with sloping configuration. The relationship between the behavioral and electrophysiological intensity functions was examined at individual intensities across the range of the functions for each subject. A significant relationship was obtained between loudness and the ABR wave V LIFs for the groups with normal hearing and flat configuration of cochlear hearing loss; the association was not significant (p = 0.10) for the group with a sloping configuration of cochlear hearing loss. The results of this study established a relationship between loudness and the ABR wave V latency for listeners with normal hearing, and flat cochlear hearing loss. In listeners with a sloping configuration of cochlear hearing loss, the relationship was not significant. This suggests that the click-evoked ABR may be used to estimate loudness growth at least for individuals with normal hearing and those with a flat configuration of cochlear hearing loss. Predictive equations were derived to estimate loudness growth for these groups. The use of frequency-specific stimuli may provide more precise information on the nature of the relationship between loudness growth and the ABR wave V latency, particularly for listeners with sloping configurations of cochlear hearing loss.

Radionuclide concentrations in benthic invertebrates from Amchitka and Kiska Islands in the Aleutian Chain, Alaska.

PubMed

Burger, Joanna; Gochfeld, Michael; Jewett, Stephen C

2007-05-01

Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U) were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965-1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 +/- 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 +/- 0.804 Bq/kg) and 238U (0.730 +/- 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as 'shellfish', for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.

[Applied anatomy of scala tympani inlet related to cochlear implantation].

PubMed

Zou, Tuanming; Guo, Menghe; Zhang, Hongzheng; Shu, Fan; Xie, Nanping

2012-06-01

To investigate the related parameters of the temporal bone structure for determining the position of implanting electrode into the scala tympani in cochlear implantation surgery through the facial recess and epitympanum approach. In a surgical simulation experiment, 20 human temporal bones were studied and measured to determine the related parameters of the temporal bone structure. The distance 5.91∓0.29 mm between the short process of the incus and the round window niche, 2.11∓0.18 mm between the stapes and the round window niche, 6.70∓0.19 mm between the facial nerve in the perpendicular paragraph and the round window niche, 2.22∓0.21 mm from the pyramidal eminence to the round window, and 2.16∓0.14 mm between the stapes and the round window. The minimal distance between the implanting electrode and the vestibular window was 2.12∓0.19 mm. The distance between the cochleariform process and the round window niche was 3.79∓0.17 mm. The position of the cochlear electrode array insertion into the second cochlear turn was 2.25∓0.13 mm under the stapes. The location of the cochlear electrode array insertion into the second cochlear turn was 2.28∓0.20 mm inferior to the pyramidal eminence. These parameters provide a reference value to determine the different positions of cochlear electrode array insertion into the scale tympani in different patients.

Sequential Bilateral Cochlear Implantation in a Patient with Bilateral Meniere’s Disease

PubMed Central

Holden, Laura K.; Neely, J. Gail; Gotter, Brenda D.; Mispagel, Karen M.; Firszt, Jill B.

2012-01-01

This case study describes a 45 year old female with bilateral, profound sensorineural hearing loss due to Meniere’s disease. She received her first cochlear implant in the right ear in 2008 and the second cochlear implant in the left ear in 2010. The case study examines the enhancement to speech recognition, particularly in noise, provided by bilateral cochlear implants. Speech recognition tests were administered prior to obtaining the second implant and at a number of test intervals following activation of the second device. Speech recognition in quiet and noise as well as localization abilities were assessed in several conditions to determine bilateral benefit and performance differences between ears. The results of the speech recognition testing indicated a substantial improvement in the patient’s ability to understand speech in noise and her ability to localize sound when using bilateral cochlear implants compared to using a unilateral implant or an implant and a hearing aid. In addition, the patient reported considerable improvement in her ability to communicate in daily life when using bilateral implants versus a unilateral implant. This case suggests that cochlear implantation is a viable option for patients who have lost their hearing to Meniere’s disease even when a number of medical treatments and surgical interventions have been performed to control vertigo. In the case presented, bilateral cochlear implantation was necessary for this patient to communicate successfully at home and at work. PMID:22463939

Electrical resistivity measurements in the mammalian cochlea after neural degeneration.

PubMed

Micco, Alan G; Richter, Claus-Peter

2006-08-01

In the present series of experiments, the effect of neural degeneration on the cochlear structure electrical resistivities was evaluated to test if it alters the current flow in the cochlea and if increased current levels are needed to stimulate the impaired cochlea. In cochlear implants, frequency information is encoded in part by stimulating discrete populations of spiral ganglion cells along the cochlea. However, electrical properties of the cochlear structures result in shunting of the current away from the auditory neurons. This consumes energy, makes cochlear implants less efficient, and drastically reduces battery life. Models of the electrically stimulated cochlea serve to make predictions on current paths using modified and improved cochlear implant electrodes. However, one of the model's shortcomings is that most of the values for tissue impedances are not direct measurements. They are derived from bulk impedance measurements, which are fitted to lumped-element models. The four-electrode reflection-coefficient technique was used to measure resistivities in the gerbil cochlea. In vivo and in vitro (the hemicochlea) models were used. Measurements were made in normal and in deafened animals. Cochlear damage was induced by neomycin injection into the animals' middle ears. Neural degeneration was allowed to occur over 2 months before performing the measurements in the deafened animals. The resistivity values in deafened animals were smaller than in the normal-hearing animals, thus altering the current flow within the cochlea. Resistivity changes and subsequent changes in current path should be considered in future designs of cochlear implants.

Electric charge requirements of pediatric cochlear implant recipients enrolled in the Childhood Development After Cochlear Implantation study.

PubMed

Zwolan, Teresa A; O'Sullivan, Mary Beth; Fink, Nancy E; Niparko, John K

2008-02-01

To evaluate mapping characteristics of children with cochlear implants who are enrolled in the Childhood Development After Cochlear Implantation (CDACI) multicenter study. Longitudinal evaluation during 24 months of speech processor maps of children with cochlear implants prospectively enrolled in the study. Six tertiary referral centers. One hundred eighty-eight children enrolled in the CDACI study who were 5 years old or younger at the time of enrollment. Of these children, 184 received unilateral implants, and 4 received simultaneous bilateral implants. Children attended regular mapping sessions at their implant clinic as part of the study protocol. Maps were examined for each subject at 4 different time intervals: at device activation and 6, 12, and 24 months postactivation. Mean C/M levels (in charge per phase) were compared for 4 different time intervals, for 3 different devices, for 6 different implant centers, and for children with normal and abnormal cochleae. All 3 types of implant devices demonstrate significant increases in C/M levels between device activation and the 24-month appointment. Significant differences in mean C/M levels were noted between devices. Children with cochlear anomalies demonstrate significantly greater C/M levels than children with normal cochleae. The CDACI study has enabled us to evaluate the mapping characteristics of pediatric patients who use 3 different devices and were implanted at a variety of implant centers. Analysis of such data enables us to better understand the mapping characteristics of children with cochlear implants.

Early Sign Language Experience Goes Along with an Increased Cross-modal Gain for Affective Prosodic Recognition in Congenitally Deaf CI Users.

PubMed

Fengler, Ineke; Delfau, Pia-Céline; Röder, Brigitte

2018-04-01

It is yet unclear whether congenitally deaf cochlear implant (CD CI) users' visual and multisensory emotion perception is influenced by their history in sign language acquisition. We hypothesized that early-signing CD CI users, relative to late-signing CD CI users and hearing, non-signing controls, show better facial expression recognition and rely more on the facial cues of audio-visual emotional stimuli. Two groups of young adult CD CI users-early signers (ES CI users; n = 11) and late signers (LS CI users; n = 10)-and a group of hearing, non-signing, age-matched controls (n = 12) performed an emotion recognition task with auditory, visual, and cross-modal emotionally congruent and incongruent speech stimuli. On different trials, participants categorized either the facial or the vocal expressions. The ES CI users more accurately recognized affective prosody than the LS CI users in the presence of congruent facial information. Furthermore, the ES CI users, but not the LS CI users, gained more than the controls from congruent visual stimuli when recognizing affective prosody. Both CI groups performed overall worse than the controls in recognizing affective prosody. These results suggest that early sign language experience affects multisensory emotion perception in CD CI users.

Speech Perception for Adults Who Use Hearing Aids in Conjunction with Cochlear Implants in Opposite Ears

ERIC Educational Resources Information Center

Mok, Mansze; Grayden, David; Dowell, Richard C.; Lawrence, David

2006-01-01

This study aimed to (a) investigate the effect of using a hearing aid in conjunction with a cochlear implant in opposite ears on speech perception in quiet and in noise, (b) identify the speech information obtained from a hearing aid that is additive to the information obtained from a cochlear implant, and (c) explore the relationship between…

Sirviendo a los estudiantes sordos que tienen Los implantes cocleares. Hoja de consejos de PEPNet (Serving Deaf Students Who Have Cochlear Implants. PEPNet Tipsheet)

ERIC Educational Resources Information Center

Clark, Catherine

2010-01-01

This version of "Serving Deaf Students Who Have Cochlear Implants. PEPNet Tipsheet," written in Spanish, describes how cochlear implants (CIs) work. CIs are complex electronic devices surgically implanted under the skin behind the ear. These devices utilize electrodes placed in the inner ear (the cochlea) to stimulate the auditory nerve of…

Sensitivity in Interactions between Hearing Mothers and their Toddlers with Hearing Loss: The Effect of Cochlear Implantation

ERIC Educational Resources Information Center

Bakar, Zaharah Abu; Brown, P. Margaret; Remine, Maria D.

2010-01-01

This study investigated the potential effects of cochlear implantation and age at implantation on maternal interactional sensitivity. Three groups of dyads were studied at two points over 1 year. The hearing aid (HA) group wore hearing aids throughout the study, the early cochlear implanted (ECI) group were implanted prior to 22 months of age, and…

The Relation Between Child Versus Parent Report of Chronic Fatigue and Language/Literacy Skills in School-Age Children with Cochlear Implants.

PubMed

Werfel, Krystal L; Hendricks, Alison Eisel

2016-01-01

Preliminary evidence suggests that children with hearing loss experience elevated levels of chronic fatigue compared with children with normal hearing. Chronic fatigue is associated with decreased academic performance in many clinical populations. Children with cochlear implants as a group exhibit deficits in language and literacy skills; however, the relation between chronic fatigue and language and literacy skills for children with cochlear implants is unclear. The purpose of this study was to explore subjective ratings of chronic fatigue by children with cochlear implants and their parents, as well as the relation between chronic fatigue and language and literacy skills in this population. Nineteen children with cochlear implants in grades 3 to 6 and one of their parents separately completed a subjective chronic fatigue scale, on which they rated how much the child experienced physical, sleep/rest, and cognitive fatigue over the past month. In addition, children completed an assessment battery that included measures of speech perception, oral language, word reading, and spelling. Children and parents reported different levels of chronic child physical and sleep/rest fatigue. In both cases, parents reported significantly less fatigue than did children. Children and parents did not report different levels of chronic child cognitive fatigue. Child report of physical fatigue was related to speech perception, language, reading, and spelling. Child report of sleep/rest and cognitive fatigue was related to speech perception and language but not to reading or spelling. Parent report of child fatigue was not related to children's language and literacy skills. Taken as a whole, results suggested that parents under-estimate the fatigue experienced by children with cochlear implants. Child report of physical fatigue was robustly related to language and literacy skills. Children with cochlear implants are likely more accurate at reporting physical fatigue than cognitive fatigue. Clinical practice should take fatigue into account when developing treatment plans for children with cochlear implants, and research should continue to develop a comprehensive model of fatigue in children with cochlear implants.

Subcortical amplitude modulation encoding deficits suggest evidence of cochlear synaptopathy in normal-hearing 18-19 year olds with higher lifetime noise exposure.

PubMed

Paul, Brandon T; Waheed, Sajal; Bruce, Ian C; Roberts, Larry E

2017-11-01

Noise exposure and aging can damage cochlear synapses required for suprathreshold listening, even when cochlear structures needed for hearing at threshold remain unaffected. To control for effects of aging, behavioral amplitude modulation (AM) detection and subcortical envelope following responses (EFRs) to AM tones in 25 age-restricted (18-19 years) participants with normal thresholds, but different self-reported noise exposure histories were studied. Participants with more noise exposure had smaller EFRs and tended to have poorer AM detection than less-exposed individuals. Simulations of the EFR using a well-established cochlear model were consistent with more synaptopathy in participants reporting greater noise exposure.

Imaging cochlear soft tissue displacement with coherent x-rays

NASA Astrophysics Data System (ADS)

Rau, Christoph; Richter, Claus-Peter

2015-10-01

At present, imaging of cochlear mechanics at mid-cochlear turns has not been accomplished. Although challenging, this appears possible with partially coherent hard x-rays. The present study shows results from stroboscopic x-ray imaging of a test object at audio frequencies. The vibration amplitudes were quantified. In a different set of experiments, an intact and calcified gerbil temporal bone was used to determine displacements of the reticular lamina, tectorial membrane, and Reissner’s membrane with the Lucas and Kanade video flow algorithm. The experiments validated high frequency x-ray imaging and imaging in a calcified cochlea. The present work is key for future imaging of cochlear micromechanics at a high spatial resolution.

Relating the variability of tone-burst otoacoustic emission and auditory brainstem response latencies to the underlying cochlear mechanics

NASA Astrophysics Data System (ADS)

Verhulst, Sarah; Shera, Christopher A.

2015-12-01

Forward and reverse cochlear latency and its relation to the frequency tuning of the auditory filters can be assessed using tone bursts (TBs). Otoacoustic emissions (TBOAEs) estimate the cochlear roundtrip time, while auditory brainstem responses (ABRs) to the same stimuli aim at measuring the auditory filter buildup time. Latency ratios are generally close to two and controversy exists about the relationship of this ratio to cochlear mechanics. We explored why the two methods provide different estimates of filter buildup time, and ratios with large inter-subject variability, using a time-domain model for OAEs and ABRs. We compared latencies for twenty models, in which all parameters but the cochlear irregularities responsible for reflection-source OAEs were identical, and found that TBOAE latencies were much more variable than ABR latencies. Multiple reflection-sources generated within the evoking stimulus bandwidth were found to shape the TBOAE envelope and complicate the interpretation of TBOAE latency and TBOAE/ABR ratios in terms of auditory filter tuning.

Long latency auditory evoked potentials in children with cochlear implants: systematic review.

PubMed

Silva, Liliane Aparecida Fagundes; Couto, Maria Inês Vieira; Matas, Carla Gentile; Carvalho, Ana Claudia Martinho de

2013-11-25

The aim of this study was to analyze the findings on Cortical Auditory Evoked Potentials in children with cochlear implant through a systematic literature review. After formulation of research question and search of studies in four data bases with the following descriptors: electrophysiology (eletrofisiologia), cochlear implantation (implante coclear), child (criança), neuronal plasticity (plasticidade neuronal) and audiology (audiologia), were selected articles (original and complete) published between 2002 and 2013 in Brazilian Portuguese or English. A total of 208 studies were found; however, only 13 contemplated the established criteria and were further analyzed; was made data extraction for analysis of methodology and content of the studies. The results described suggest rapid changes in P1 component of Cortical Auditory Evoked Potentials in children with cochlear implants. Although there are few studies on the theme, cochlear implant has been shown to produce effective changes in central auditory path ways especially in children implanted before 3 years and 6 months of age.

Corticofugal modulation of peripheral auditory responses

PubMed Central

Terreros, Gonzalo; Delano, Paul H.

2015-01-01

The auditory efferent system originates in the auditory cortex and projects to the medial geniculate body (MGB), inferior colliculus (IC), cochlear nucleus (CN) and superior olivary complex (SOC) reaching the cochlea through olivocochlear (OC) fibers. This unique neuronal network is organized in several afferent-efferent feedback loops including: the (i) colliculo-thalamic-cortico-collicular; (ii) cortico-(collicular)-OC; and (iii) cortico-(collicular)-CN pathways. Recent experiments demonstrate that blocking ongoing auditory-cortex activity with pharmacological and physical methods modulates the amplitude of cochlear potentials. In addition, auditory-cortex microstimulation independently modulates cochlear sensitivity and the strength of the OC reflex. In this mini-review, anatomical and physiological evidence supporting the presence of a functional efferent network from the auditory cortex to the cochlear receptor is presented. Special emphasis is given to the corticofugal effects on initial auditory processing, that is, on CN, auditory nerve and cochlear responses. A working model of three parallel pathways from the auditory cortex to the cochlea and auditory nerve is proposed. PMID:26483647

Technical devices for hearing-impaired individuals: cochlear implants and brain stem implants - developments of the last decade

PubMed Central

Müller, Joachim

2005-01-01

Over the past two decades, the fascinating possibilities of cochlear implants for congenitally deaf or deafened children and adults developed tremendously and created a rapidly developing interdisciplinary research field. The main advancements of cochlear implantation in the past decade are marked by significant improvement of hearing and speech understanding in CI users. These improvements are attributed to the enhancement of speech coding strategies. The Implantation of more (and increasingly younger) children as well as the possibilities of the restoration of binaural hearing abilities with cochlear implants reflect the high standards reached by this development. Despite this progress, modern cochlear implants do not yet enable normal speech understanding, not even for the best patients. In particular speech understanding in noise remains problematic [1]. Until the mid 1990ies research concentrated on unilateral implantation. Remarkable and effective improvements have been made with bilateral implantation since 1996. Nowadays an increasing numbers of patients enjoy these benefits. PMID:22073052

Technical devices for hearing-impaired individuals: cochlear implants and brain stem implants - developments of the last decade.

PubMed

Müller, Joachim

2005-01-01

Over the past two decades, the fascinating possibilities of cochlear implants for congenitally deaf or deafened children and adults developed tremendously and created a rapidly developing interdisciplinary research field.The main advancements of cochlear implantation in the past decade are marked by significant improvement of hearing and speech understanding in CI users. These improvements are attributed to the enhancement of speech coding strategies.The Implantation of more (and increasingly younger) children as well as the possibilities of the restoration of binaural hearing abilities with cochlear implants reflect the high standards reached by this development. Despite this progress, modern cochlear implants do not yet enable normal speech understanding, not even for the best patients. In particular speech understanding in noise remains problematic [1]. Until the mid 1990ies research concentrated on unilateral implantation. Remarkable and effective improvements have been made with bilateral implantation since 1996. Nowadays an increasing numbers of patients enjoy these benefits.

Characteristics and pathogenesis of facial nerve stimulation after cochlear implant surgeries: A single-center retrospective analysis from 1,151 patients.

PubMed

Kim, Y R; Yoo, M H; Lee, J Y; Yang, C J; Park, J W; Kang, B C; Kang, W S; Ahn, J H; Chung, J W; Park, H J

2018-05-29

Incidence of facial nerve stimulation (FNS) was 2.8% (32 out of 1151) and higher in ears with cochlear anomaly (6.4%, 25 out of 391) than without cochlear anomaly (0.9%, 7 out of 760). FNS occurred at various current levels and locations of electrodes by different mechanisms related to incomplete insertion of electrodes, cochleo-facial dehiscence, and types of cochlear anomalies. FNS at apical electrodes related to cochleo-facial dehiscence with low current levels, and FNS at basal electrodes with high current levels and partial insertion of electrodes. FNS at most electrodes with high current levels was the most common type in patients with a common cavity or narrowing of the bony cochlear nerve canal. Understanding the mechanisms of FNS might provide insight for preventing FNS when performing CI surgeries. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Cochlear implantation in Waardenburg syndrome: The Indian scenario.

PubMed

Deka, Ramesh Chandra; Sikka, Kapil; Chaturvedy, Gaurav; Singh, Chirom Amit; Venkat Karthikeyan, C; Kumar, Rakesh; Agarwal, Shivani

2010-10-01

Children with Waardenburg syndrome (WS) exhibiting normal inner ear anatomy, like those included in our cohort, derive significant benefit from cochlear implantation and results are comparable to those reported for the general population of implanted children. The patient population of WS accounts for approximately 2% of congenitally deaf children. The purpose of this retrospective case review was to describe the outcomes for those children with WS who have undergone cochlear implantation. On retrospective chart review, there were four cases with WS who underwent cochlear implantation. These cases were assessed for age at implantation, clinical and radiological features, operative and perioperative course, and performance outcomes. Auditory perception and speech production ability were evaluated using categories of auditory performance (CAP), meaningful auditory integration scales (MAIS), and speech intelligibility rating (SIR) during the follow-up period. In this group of children with WS, with a minimum follow-up of 12 months, the CAP score ranged from 3 to 5, MAIS from 25 to 30, and SIR was 3. These scores are comparable with those of other cochlear implantees.

Libyan cochlear implant programme: achievements, difficulties, and future goals

PubMed Central

Salamat, Ali; Esriti, Anwer; Ehtuish, Asia; El-Ogbi, Samya

2011-01-01

Cochlear implantation has become established worldwide as a safe and effective method of auditory rehabilitation of selected severely and profound deaf children and adults. Over 100,000 patients have received cochlear implants worldwide with the paediatric population proving to be the main beneficiaries. The Libyan cochlear implant programme was set up in 2004. Data relating to the patients who received cochlear implantation at Tripoli Medical Centre between October 2007 and February 2010 were analysed. Implant operations were performed on 37 patients. All patients received Med-El SONATATI100 devices. Thirty-four (91.9%) of these patients were children, whilst three (8.1%) were adults. Combined, congenital hearing loss (56.8%) and perinatal/neonatal (29.7%) were the two main aetiological factors in children. Seventeen patients (45.9%) had a positive family history of deafness. Sixteen patients (43.2%) were born to blood-related parents. The overall rate of minor and major complications was 16.2%, which is comparable to previous studies. PMID:21694783

Libyan cochlear implant programme: achievements, difficulties, and future goals.

PubMed

Salamat, Ali; Esriti, Anwer; Ehtuish, Asia; El-Ogbi, Samya

2011-01-01

Cochlear implantation has become established worldwide as a safe and effective method of auditory rehabilitation of selected severely and profound deaf children and adults. Over 100,000 patients have received cochlear implants worldwide with the paediatric population proving to be the main beneficiaries. The Libyan cochlear implant programme was set up in 2004. Data relating to the patients who received cochlear implantation at Tripoli Medical Centre between October 2007 and February 2010 were analysed. Implant operations were performed on 37 patients. All patients received Med-El SONATA(TI) (100) devices. Thirty-four (91.9%) of these patients were children, whilst three (8.1%) were adults. Combined, congenital hearing loss (56.8%) and perinatal/neonatal (29.7%) were the two main aetiological factors in children. Seventeen patients (45.9%) had a positive family history of deafness. Sixteen patients (43.2%) were born to blood-related parents. The overall rate of minor and major complications was 16.2%, which is comparable to previous studies.

Auditory Spatial Perception: Auditory Localization

DTIC Science & Technology

2012-05-01

cochlear nucleus, TB – trapezoid body, SOC – superior olivary complex, LL – lateral lemniscus, IC – inferior colliculus. Adapted from Aharonson and...Figure 5. Auditory pathways in the central nervous system. LE – left ear, RE – right ear, AN – auditory nerve, CN – cochlear nucleus, TB...fibers leaving the left and right inner ear connect directly to the synaptic inputs of the cochlear nucleus (CN) on the same (ipsilateral) side of

Low Level Chemical Toxicity: Relevance to Chemical Agent Defense

DTIC Science & Technology

2005-07-01

elevation in stress hormones in the blood serum. Electron microscropy indicated no damage to cochlear tissues of the ear (not shown). At the...neural activity occurring primarily in the cochlear nucleus of the brainstem auditory pathway. Peak II is usually the last major peak to disappear...IV). Peak II is generally the strongest peak and is regarded as a putative indicator of neural activity occurring primarily in the cochlear nucleus

Sex Difference in Susceptibility and Resistance to Noise-Induced Hearing Loss in Chinchillas

DTIC Science & Technology

2000-10-01

Estradiol assays Blood samples were collected from deeply anesthetized chinchillas prior to cochlear histology. The blood samples were centrifuged to...pattern of hearing loss and cochlear damage for male and female chinchillas Gender differences have been reported in susceptibility to NIHL, both...Given the results of physiological testing (IC-EVPs and CDPs), the results of cochlear histology were somewhat surprising (see McFadden et al., 1999

Microsurgical Decompression of the Cochlear Nerve to Treat Disabling Tinnitus via an Endoscope-Assisted Retrosigmoid Approach: The Padua Experience.

PubMed

Di Stadio, Arianna; Colangeli, Roberta; Dipietro, Laura; Martini, Alessandro; Parrino, Daniela; Nardello, Ennio; D'Avella, Domenico; Zanoletti, Elisabetta

2018-05-01

The use of surgical cochlear nerve decompression is controversial. This study aimed at investigating the safety and validity of microsurgical decompression via an endoscope-assisted retrosigmoid approach to treat tinnitus in patients with neurovascular compression of the cochlear nerve. Three patients with disabling tinnitus resulting from a loop in the internal auditory canal were evaluated with magnetic resonance imaging and tests of pure tone auditory, tinnitus, and auditory brain response (ABR) to identify the features of the cochlear nerve involvement. We observed a loop with a caliber greater than 0.8 mm in all patients. Patients were treated via an endoscope-assisted retrosigmoid microsurgical decompression. After surgery, none of the patients reported short-term or long-term complications. After surgery, tinnitus resolved immediately in 2 patients, whereas in the other patient symptoms persisted although they improved; in all patients, hearing was preserved and ABR improved. Microsurgical decompression via endoscope-assisted retrosigmoid approach is a promising, safe, and valid procedure for treating tinnitus caused by cochlear nerve compression. This procedure should be considered in patients with disabling tinnitus who have altered ABR and a loop that has a caliber greater than 0.8 mm and is in contact with the cochlear nerve. Copyright © 2018 Elsevier Inc. All rights reserved.

Inner-ear sound pressures near the base of the cochlea in chinchilla: Further investigation

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2013-01-01

The middle-ear pressure gain GMEP, the ratio of sound pressure in the cochlear vestibule PV to sound pressure at the tympanic membrane PTM, is a descriptor of middle-ear sound transfer and the cochlear input for a given stimulus in the ear canal. GMEP and the cochlear partition differential pressure near the cochlear base ΔPCP, which determines the stimulus for cochlear partition motion and has been linked to hearing ability, were computed from simultaneous measurements of PV, PTM, and the sound pressure in scala tympani near the round window PST in chinchilla. GMEP magnitude was approximately 30 dB between 0.1 and 10 kHz and decreased sharply above 20 kHz, which is not consistent with an ideal transformer or a lossless transmission line. The GMEP phase was consistent with a roughly 50-μs delay between PV and PTM. GMEP was little affected by the inner-ear modifications necessary to measure PST. GMEP is a good predictor of ΔPCP at low and moderate frequencies where PV ⪢ PST but overestimates ΔPCP above a few kilohertz where PV ≈ PST. The ratio of PST to PV provides insight into the distribution of sound pressure within the cochlear scalae. PMID:23556590

Single and Multiple Microphone Noise Reduction Strategies in Cochlear Implants

PubMed Central

Azimi, Behnam; Hu, Yi; Friedland, David R.

2012-01-01

To restore hearing sensation, cochlear implants deliver electrical pulses to the auditory nerve by relying on sophisticated signal processing algorithms that convert acoustic inputs to electrical stimuli. Although individuals fitted with cochlear implants perform well in quiet, in the presence of background noise, the speech intelligibility of cochlear implant listeners is more susceptible to background noise than that of normal hearing listeners. Traditionally, to increase performance in noise, single-microphone noise reduction strategies have been used. More recently, a number of approaches have suggested that speech intelligibility in noise can be improved further by making use of two or more microphones, instead. Processing strategies based on multiple microphones can better exploit the spatial diversity of speech and noise because such strategies rely mostly on spatial information about the relative position of competing sound sources. In this article, we identify and elucidate the most significant theoretical aspects that underpin single- and multi-microphone noise reduction strategies for cochlear implants. More analytically, we focus on strategies of both types that have been shown to be promising for use in current-generation implant devices. We present data from past and more recent studies, and furthermore we outline the direction that future research in the area of noise reduction for cochlear implants could follow. PMID:22923425

TNF-α inhibition using etanercept prevents noise-induced hearing loss by improvement of cochlear blood flow in vivo.

PubMed

Arpornchayanon, Warangkana; Canis, Martin; Ihler, Friedrich; Settevendemie, Claudia; Strieth, Sebastian

2013-08-01

Exposure to loud noise can impair cochlear microcirculation and cause noise-induced hearing loss (NIHL). TNF-α signaling has been shown to be activated in NIHL and to control spiral modiolar artery vasoconstriction that regulates cochlear microcirculation. It was the aim of this experimental study to analyse the effects of the TNF-α inhibitor etanercept on cochlear microcirculation and hearing threshold shift in NIHL in vivo. After assessment of normacusis using ABR, loud noise (106 dB SPL, 30 minutes) was applied on both ears in guinea pigs. Etanercept was administered systemically after loud noise exposure while control animals received a saline solution. In vivo fluorescence microscopy of strial capillaries was performed after surgical exposure of the cochlea for microcirculatory analysis. ABR measurements were derived from the contralateral ear. Guinea pigs (n = 6, per group). Compared to controls, cochlear blood flow in strial capillary segments was significantly increased in etanercept-treated animals. Additionally, hearing threshold was preserved in animals receiving the TNF-α inhibitor in contrast to a significant threshold raising in controls. TNF-α inhibition using etanercept improves cochlear microcirculation and protects hearing levels after loud noise exposure and appears as a promising treatment strategy for human NIHL.

A prospective study evaluating cochlear implant management skills: development and validation of the Cochlear Implant Management Skills survey.

PubMed

Bennett, R J; Jayakody, D M P; Eikelboom, R H; Taljaard, D S; Atlas, M D

2016-02-01

To investigate the ability of cochlear implant (CI) recipients to physically handle and care for their hearing implant device(s) and to identify factors that may influence skills. To assess device management skills, a clinical survey was developed and validated on a clinical cohort of CI recipients. Survey development and validation. A prospective convenience cohort design study. Specialist hearing implant clinic. Forty-nine post-lingually deafened, adult CI recipients, at least 12 months postoperative. Survey test-retest reliability, interobserver reliability and responsiveness. Correlations between management skills and participant demographic, audiometric, clinical outcomes and device factors. The Cochlear Implant Management Skills survey was developed, demonstrating high test-retest reliability (0.878), interobserver reliability (0.972) and responsiveness to intervention (skills training) [t(20) = -3.913, P = 0.001]. Cochlear Implant Management Skills survey scores range from 54.69% to 100% (mean: 83.45%, sd: 12.47). No associations were found between handling skills and participant factors. This is the first study to demonstrate a range in cochlear implant device handling skills in CI recipients and offers clinicians and researchers a tool to systematically and objectively identify shortcomings in CI recipients' device handling skills. © 2015 John Wiley & Sons Ltd.

Comparison of auditory comprehension skills in children with cochlear implant and typically developing children.

PubMed

Mandal, Joyanta Chandra; Kumar, Suman; Roy, Sumit

2016-12-01

The main goal of this study was to obtain auditory comprehension skills of native Hindi speaking children with cochlear implant and typically developing children across the age of 3-7 years and compare the scores between two groups. A total of sixty Hindi speaking participants were selected for the study. They were divided into two groups- Group-A consisted of thirty children with normal hearing and Group-B thirty children using cochlear implants. To assess the auditory comprehension skills, Test of auditory comprehension in Hindi (TACH) was used. The participant was required to point to one of three pictures which would best correspond to the stimulus presented. Correct answers were scored as 1 and incorrect answers as 0. TACH was administered on for both groups. Independent t-test was applied and it was found that auditory comprehension scores of children using cochlear implant were significantly poorer than the score of children with normal hearing for all three subtests. Pearson's correlation coefficient revealed poor correlation between the scores of children with normal hearing and children using cochlear implant. The results of this study suggest that children using cochlear implant have poor auditory comprehension skills than children with normal hearing. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A longitudinal study of the bilateral benefit in children with bilateral cochlear implants.

PubMed

Asp, Filip; Mäki-Torkko, Elina; Karltorp, Eva; Harder, Henrik; Hergils, Leif; Eskilsson, Gunnar; Stenfelt, Stefan

2015-02-01

To study the development of the bilateral benefit in children using bilateral cochlear implants by measurements of speech recognition and sound localization. Bilateral and unilateral speech recognition in quiet, in multi-source noise, and horizontal sound localization was measured at three occasions during a two-year period, without controlling for age or implant experience. Longitudinal and cross-sectional analyses were performed. Results were compared to cross-sectional data from children with normal hearing. Seventy-eight children aged 5.1-11.9 years, with a mean bilateral cochlear implant experience of 3.3 years and a mean age of 7.8 years, at inclusion in the study. Thirty children with normal hearing aged 4.8-9.0 years provided normative data. For children with cochlear implants, bilateral and unilateral speech recognition in quiet was comparable whereas a bilateral benefit for speech recognition in noise and sound localization was found at all three test occasions. Absolute performance was lower than in children with normal hearing. Early bilateral implantation facilitated sound localization. A bilateral benefit for speech recognition in noise and sound localization continues to exist over time for children with bilateral cochlear implants, but no relative improvement is found after three years of bilateral cochlear implant experience.

Cochlear implanted pupils in Scottish schools: 4-year school attainment data (2000-2004).

PubMed

Thoutenhoofd, Ernst

2006-01-01

The Achievements of Deaf Pupils in Scotland (ADPS) project has been tracking the educational attainment of deaf pupils in Scotland's schools since 2000. At the time of writing, the database contains records for 1,752 deaf pupils (2000-2005). Here 4-year aggregate educational attainment data are reported for a subset of 152 school-aged deaf pupils with cochlear implants notified to the ADPS database between June 2000 and June 2004. The data describe primary and secondary school results in reading, writing, and math for this subgroup, as well as placement and communication characteristics. The educational attainment of the group of deaf pupils with cochlear implants is clearly marked when the deaf pupil population is disaggregated for hearing loss, achieving comparatively higher average attainment in both 5-14 Curriculum National Tests (Mathematics in particular) and Standard Grades. Therefore the gap in performance relative to the national population data is reduced for those deaf pupils, although it still widens at higher levels of achievement for the National Tests. Although most pupils with cochlear implants are placed in the mainstream, there is no pattern of migration toward mainstream schools. Some deaf pupils with cochlear implants moved out of mainstream to other types of placement, and this has implications for health-economic cost-utility assessments of cochlear implantation that favor mainstream education by drawing upon the relative cost of different placement types. These findings suggest that the ADPS program of research can contribute school outcome data as valuable real-life outcome measures in wider assessments of the benefit of cochlear implants to deaf children and deaf young people.

Musical experience sharpens human cochlear tuning.

PubMed

Bidelman, Gavin M; Nelms, Caitlin; Bhagat, Shaum P

2016-05-01

The mammalian cochlea functions as a filter bank that performs a spectral, Fourier-like decomposition on the acoustic signal. While tuning can be compromised (e.g., broadened with hearing impairment), whether or not human cochlear frequency resolution can be sharpened through experiential factors (e.g., training or learning) has not yet been established. Previous studies have demonstrated sharper psychophysical tuning curves in trained musicians compared to nonmusicians, implying superior peripheral tuning. However, these findings are based on perceptual masking paradigms, and reflect engagement of the entire auditory system rather than cochlear tuning, per se. Here, by directly mapping physiological tuning curves from stimulus frequency otoacoustic emissions (SFOAEs)-cochlear emitted sounds-we show that estimates of human cochlear tuning in a high-frequency cochlear region (4 kHz) is further sharpened (by a factor of 1.5×) in musicians and improves with the number of years of their auditory training. These findings were corroborated by measurements of psychophysical tuning curves (PTCs) derived via simultaneous masking, which similarly showed sharper tuning in musicians. Comparisons between SFOAE and PTCs revealed closer correspondence between physiological and behavioral curves in musicians, indicating that tuning is also more consistent between different levels of auditory processing in trained ears. Our findings demonstrate an experience-dependent enhancement in the resolving power of the cochlear sensory epithelium and the spectral resolution of human hearing and provide a peripheral account for the auditory perceptual benefits observed in musicians. Both local and feedback (e.g., medial olivocochlear efferent) mechanisms are discussed as potential mechanisms for experience-dependent tuning. Copyright © 2016 Elsevier B.V. All rights reserved.

Using Evoked Potentials to Match Interaural Electrode Pairs with Bilateral Cochlear Implants

PubMed Central

Delgutte, Bertrand

2007-01-01

Bilateral cochlear implantation seeks to restore the advantages of binaural hearing to the profoundly deaf by providing binaural cues normally important for accurate sound localization and speech reception in noise. Psychophysical observations suggest that a key issue for the implementation of a successful binaural prosthesis is the ability to match the cochlear positions of stimulation channels in each ear. We used a cat model of bilateral cochlear implants with eight-electrode arrays implanted in each cochlea to develop and test a noninvasive method based on evoked potentials for matching interaural electrodes. The arrays allowed the cochlear location of stimulation to be independently varied in each ear. The binaural interaction component (BIC) of the electrically evoked auditory brainstem response (EABR) was used as an assay of binaural processing. BIC amplitude peaked for interaural electrode pairs at the same relative cochlear position and dropped with increasing cochlear separation in either direction. To test the hypothesis that BIC amplitude peaks when electrodes from the two sides activate maximally overlapping neural populations, we measured multiunit neural activity along the tonotopic gradient of the inferior colliculus (IC) with 16-channel recording probes and determined the spatial pattern of IC activation for each stimulating electrode. We found that the interaural electrode pairings that produced the best aligned IC activation patterns were also those that yielded maximum BIC amplitude. These results suggest that EABR measurements may provide a method for assigning frequency–channel mappings in bilateral implant recipients, such as pediatric patients, for which psychophysical measures of pitch ranking or binaural fusion are unavailable. PMID:17225976

Using evoked potentials to match interaural electrode pairs with bilateral cochlear implants.

PubMed

Smith, Zachary M; Delgutte, Bertrand

2007-03-01

Bilateral cochlear implantation seeks to restore the advantages of binaural hearing to the profoundly deaf by providing binaural cues normally important for accurate sound localization and speech reception in noise. Psychophysical observations suggest that a key issue for the implementation of a successful binaural prosthesis is the ability to match the cochlear positions of stimulation channels in each ear. We used a cat model of bilateral cochlear implants with eight-electrode arrays implanted in each cochlea to develop and test a noninvasive method based on evoked potentials for matching interaural electrodes. The arrays allowed the cochlear location of stimulation to be independently varied in each ear. The binaural interaction component (BIC) of the electrically evoked auditory brainstem response (EABR) was used as an assay of binaural processing. BIC amplitude peaked for interaural electrode pairs at the same relative cochlear position and dropped with increasing cochlear separation in either direction. To test the hypothesis that BIC amplitude peaks when electrodes from the two sides activate maximally overlapping neural populations, we measured multiunit neural activity along the tonotopic gradient of the inferior colliculus (IC) with 16-channel recording probes and determined the spatial pattern of IC activation for each stimulating electrode. We found that the interaural electrode pairings that produced the best aligned IC activation patterns were also those that yielded maximum BIC amplitude. These results suggest that EABR measurements may provide a method for assigning frequency-channel mappings in bilateral implant recipients, such as pediatric patients, for which psychophysical measures of pitch ranking or binaural fusion are unavailable.

Intracochlear administration of steroids with a catheter during human cochlear implantation: a safety and feasibility study.

PubMed

Prenzler, Nils K; Salcher, Rolf; Timm, Max; Gaertner, Lutz; Lenarz, Thomas; Warnecke, Athanasia

2018-05-14

Suppression of foreign body reaction, improvement of electrode-nerve interaction, and preservation of residual hearing are essential research topics in cochlear implantation. Intracochlear pharmaco- or cell-based therapies can open new horizons in this field. Local drug delivery strategies are desirable as higher local concentrations of agents can be realized and side effects can be minimized compared to systemic administrations. When administered locally at accessible, basal parts of the cochlea, drugs reach apical regions later and in much lower concentrations due to poor diffusion patterns in cochlear fluids. Therefore, new devices are needed to warrant rapid distribution of agents into all parts of the cochlea. Five patients received a deep intracochlear injection of triamcinolone with a specifically designed cochlear catheter during cochlear implantation right before inserting a cochlear implant electrode. As a measure for formation of fibrous tissue around the electrode, electrical impedances were measured in the operation room and over 4 months thereafter. No adverse events were observed peri- and postoperatively. The handling of the device was easy. Severe damage to the microstructure of the cochlea was excluded as far as possible by cone beam computed tomography and vestibular testing. A delayed rise of the impedances was seen in the catheter group compared to controls over all regions of the cochlea. A statistical significance, however, was only obtained at the midregion of the cochlea. Consequently, the cochlear catheter is a safe and feasible device for local drug delivery of pharmaceutical agents into deeper regions of the cochlea.

Spatial Release From Masking in Simulated Cochlear Implant Users With and Without Access to Low-Frequency Acoustic Hearing

PubMed Central

Dietz, Mathias; Hohmann, Volker; Jürgens, Tim

2015-01-01

For normal-hearing listeners, speech intelligibility improves if speech and noise are spatially separated. While this spatial release from masking has already been quantified in normal-hearing listeners in many studies, it is less clear how spatial release from masking changes in cochlear implant listeners with and without access to low-frequency acoustic hearing. Spatial release from masking depends on differences in access to speech cues due to hearing status and hearing device. To investigate the influence of these factors on speech intelligibility, the present study measured speech reception thresholds in spatially separated speech and noise for 10 different listener types. A vocoder was used to simulate cochlear implant processing and low-frequency filtering was used to simulate residual low-frequency hearing. These forms of processing were combined to simulate cochlear implant listening, listening based on low-frequency residual hearing, and combinations thereof. Simulated cochlear implant users with additional low-frequency acoustic hearing showed better speech intelligibility in noise than simulated cochlear implant users without acoustic hearing and had access to more spatial speech cues (e.g., higher binaural squelch). Cochlear implant listener types showed higher spatial release from masking with bilateral access to low-frequency acoustic hearing than without. A binaural speech intelligibility model with normal binaural processing showed overall good agreement with measured speech reception thresholds, spatial release from masking, and spatial speech cues. This indicates that differences in speech cues available to listener types are sufficient to explain the changes of spatial release from masking across these simulated listener types. PMID:26721918

Fabrication and evaluation of an improved polymer-based cochlear electrode array for atraumatic insertion.

PubMed

Gwon, Tae Mok; Min, Kyou Sik; Kim, Jin Ho; Oh, Seung Ha; Lee, Ho Sun; Park, Min-Hyun; Kim, Sung June

2015-04-01

An atraumatic cochlear electrode array has become indispensable to high-performance cochlear implants such as electric acoustic stimulation (EAS), wherein the preservation of residual hearing is significant. For an atraumatic implantation, we propose and demonstrate a new improved design of a cochlear electrode array based on liquid crystal polymer (LCP), which can be fabricated by precise batch processes and a thermal lamination process, in contrast to conventional wire-based cochlear electrode arrays. Using a thin-film process of LCP-film-mounted silicon wafer and thermal press lamination, we devise a multi-layered structure with variable layers of LCP films to achieve a sufficient degree of basal rigidity and a flexible tip. A peripheral blind via and self-aligned silicone elastomer molding process can reduce the width of the array. Measuring the insertion and extraction forces in a human scala tympani model, we investigate five human temporal bone insertion trials and record electrically evoked auditory brainstem responses (EABR) acutely in a guinea pig model. The diameters of the finalized electrode arrays are 0.3 mm (tip) and 0.75 mm (base). The insertion force with a displacement of 8 mm from a round window and the maximum extraction force are 2.4 mN and 34.0 mN, respectively. The electrode arrays can be inserted from 360° to 630° without trauma at the basal turn. The EABR data confirm the efficacy of the array. A new design of LCP-based cochlear electrode array for atraumatic implantation is fabricated. Verification indicates that foretells the development of an atraumatic cochlear electrode array and clinical implant.

Persistence, Distribution, and Impact of Distinctly Segmented Microparticles on Cochlear Health following In Vivo Infusion3*

PubMed Central

Ross, Astin M.; Rahmani, Sahar; Prieskorn, Diane M.; Dishman, Acacia F; Miller, Josef M.; Lahann, Joerg; Altschuler, Richard A.

2016-01-01

Delivery of pharmaceuticals to the cochleae of patients with auditory dysfunction could potentially have many benefits from enhancing auditory nerve survival to protecting remaining sensory cells and their neuronal connections. Treatment would require platforms to enable drug delivery directly to the cochlea and increase the potential efficacy of intervention. Cochlear implant recipients are a specific patient subset that could benefit from local drug delivery as more candidates have residual hearing; and since residual hearing directly contributes to post-implantation hearing outcomes, it requires protection from implant insertion-induced trauma. This study assessed the feasibility of utilizing microparticles for drug delivery into cochlear fluids, testing persistence, distribution, biocompatibility, and drug release characteristics. To allow for delivery of multiple therapeutics, particles were composed of two distinct compartments; one containing polylactide-co-glycolide (PLGA), and one composed of acetal-modified dextran and PLGA. Following in vivo infusion, image analysis revealed microparticle persistence in the cochlea for at least 7 days post-infusion, primarily in the first and second turns. The majority of subjects maintained or had only slight elevation in auditory brainstem response thresholds at 7 days post-infusion compared to pre-infusion baselines. There was only minor to limited loss of cochlear hair cells and negligible immune response based on CD45+ immunolabling. When Piribedil-loaded microparticles were infused, Piribedil was detectable within the cochlear fluids at 7 days post-infusion. These results indicate that segmented microparticles are relatively inert, can persist, release their contents, and be functionally and biologically compatible with cochlear function and therefore are promising vehicles for cochlear drug delivery. PMID:26841263

Prevention and management of vascular complications in middle ear and cochlear implant surgery.

PubMed

Di Lella, Filippo; Falcioni, Maurizio; Piccinini, Silvia; Iaccarino, Ilaria; Bacciu, Andrea; Pasanisi, Enrico; Cerasti, Davide; Vincenti, Vincenzo

2017-11-01

The objective of this study is to illustrate prevention strategies and management of vascular complications from the jugular bulb (JB) and internal carotid artery (ICA) during middle ear surgery or cochlear implantation. The study design is retrospective case series. The setting is tertiary referral university hospital. Patients were included if presented pre- or intraoperative evidence of high-risk anatomical anomalies of ICA or JB during middle ear or cochlear implant surgery, intraoperative vascular injury, or revision surgery after the previous iatrogenic vascular lesions. The main outcome measures are surgical outcomes and complications rate. Ten subjects were identified: three underwent cochlear implant surgery and seven underwent middle ear surgery. Among the cochlear implant patients, two presented with anomalies of the JB impeding access to the cochlear lumen and one underwent revision surgery for incorrect positioning of the array in the carotid canal. Subtotal petrosectomy was performed in all cases. Anomalies of the JB were preoperatively identified in two patients with attic and external auditory canal cholesteatoma, respectively. In a patient, a high and dehiscent JB was found during myringoplasty, while another underwent revision surgery after iatrogenic injury of the JB. A dehiscent ICA complicated middle ear effusion in one case, while in another case, a carotid aneurysm determined a cholesterol granuloma. Rupture of a pseudoaneurysm of the ICA occurred in a child during second-stage surgery and required permanent balloon occlusion without neurological complications. Knowledge of normal anatomy and its variants and preoperative imaging are the basis for prevention of vascular complications during middle ear or cochlear implant surgery.

Minocycline attenuates streptomycin-induced cochlear hair cell death by inhibiting protein nitration and poly (ADP-ribose) polymerase activation.

PubMed

Wang, Ping; Li, Haonan; Yu, Shuyuan; Jin, Peng; Hassan, Abdurahman; Du, Bo

2017-08-24

This study aimed to elucidate the protective effect of minocycline against streptomycin-induced damage of cochlear hair cells and its mechanism. Cochlear membranes were isolated from newborn Wistar rats and randomly divided into control, 500μmol/L streptomycin, 100μmol/L minocycline, and streptomycin and minocycline treatment groups. Hair cell survival was analyzed by detecting the expression of 3-nitrotyrosine (3-NT) in cochlear hair cells by immunofluorescence and an enzyme-linked immunosorbent assay. Expression of 3-NT and inducible nitric oxide synthase (iNOS), and poly (ADP-Ribose) polymerase (PARP) and caspase-3 activation were evaluated by western blotting. The results demonstrated hair cell loss at 24h after streptomycin treatment. No change was found in supporting cells of the cochleae. Minocycline pretreatment improved hair cell survival and significantly reduced the expression of iNOS and 3-NT in cochlear tissues compared with the streptomycin treatment group. PARP and caspase-3 activation was increased in the streptomycin treatment group compared with the control group, and pretreatment with minocycline decreased cleaved PARP and activated caspase-3 expression. Minocycline protected cochlear hair cells from injury caused by streptomycin in vitro. The mechanism underlying the protective effect may be associated with the inhibition of excessive formation of nitric oxide, reduction of the nitration stress reaction, and inhibition of PARP and caspase-3 activation in cochlear hair cells. Combined minocycline therapy can be applied to patients requiring streptomycin treatment. Copyright © 2017. Published by Elsevier B.V.

Cochlear Implantation After Partial or Subtotal Cochleoectomy for Intracochlear Schwannoma Removal-A Technical Report.

PubMed

Plontke, Stefan K; Kösling, Sabrina; Rahne, Torsten

2018-03-01

To describe the technique for surgical tumor removal, cochlear implant (CI) electrode placement and reconstruction of the surgical defect in patients with intracochlear schwannomas. Retrospective case review. Tertiary referral center. Ten patients (five men, five women, mean age 48 ± 12 yr) with profound or severe to profound hearing loss due to intralabyrinthine schwannomas with intracochlear location. Surgical tumor removal through extended round window approach, partial or subtotal cochleoectomy with or without labyrinthectomy and reconstruction of the surgical defect with cartilage, perichondrium or temporal muscle fascia, and bone pâté. Eight patients received a cochlear implant in the same procedure. Retrospective evaluation of clinical outcome including safety aspects (adverse events) and audiological performance at early follow up in cases of cochlear implantation. The tumor was successfully removed in all cases without macroscopic (operation microscope and endoscope) tumor remnants in the bony labyrinth apart from one case with initial transmodiolar growth. One patient needed revision surgery for labyrinthine fistula. At short-term follow up (3-month post-surgery), good hearing results with the cochlear implant were obtained in all but one patient with a word recognition score of 100% for numbers, and 64 ± 14% for monosyllables (at 65 dB SPL in quiet). Surgical tumor removal and cochlear implantation is a promising treatment strategy in the management of intralabyrinthine schwannoma with intracochlear location, further extending the indication range for cochlear implantation. It is, however, of importance to observe the long-term outcome in these patients and to address challenges like follow up with magnetic resonance imaging.

Cochlear implant with a non-removable magnet: preliminary research at 3-T MRI.

PubMed

Dubrulle, F; Sufana Iancu, A; Vincent, C; Tourrel, G; Ernst, O

2013-06-01

To perform preliminary tests in vitro and with healthy volunteers to determine the 3-T MRI compatibility of a cochlear implant with a non-removable magnet. In the in vitro phase, we tested six implants for temperature changes and internal malfunctioning. We measured the demagnetisation of 65 internal magnets with different tilt angles between the implant's magnetic field (bi) and the main magnetic field (b0). In the in vivo phase, we tested 28 operational implants attached to the scalps of volunteers with the head in three different positions. The study did not find significant temperature changes or electronic malfunction in the implants tested in vitro. We found considerable demagnetisation of the cochlear implant magnets in the in vitro and in vivo testing influenced by the position of the magnet in the main magnetic field. We found that if the bi/b0 angle is <90°, there is no demagnetisation; if the bi/b0 angle is >90°, there is demagnetisation in almost 60 % of the cases. When the angle is around 90°, the risk of demagnetisation is low (6.6 %). The preliminary results on cochlear implants with non-removable magnets indicate the need to maintain the contraindication of passage through 3-T MRI. • Magnetic resonance imaging can affect cochlear implants and vice versa. • Demagnetisation of cochlear implant correlates with the angle between bi and b0. • The position of the head in the MRI influences the demagnetisation. • Three-Tesla MRI for cochlear implants is still contraindicated. • However some future solutions are discussed.

Distortion products in auditory fMRI research: Measurements and solutions.

PubMed

Norman-Haignere, Sam; McDermott, Josh H

2016-04-01

Nonlinearities in the cochlea can introduce audio frequencies that are not present in the sound signal entering the ear. Known as distortion products (DPs), these added frequencies complicate the interpretation of auditory experiments. Sound production systems also introduce distortion via nonlinearities, a particular concern for fMRI research because the Sensimetrics earphones widely used for sound presentation are less linear than most high-end audio devices (due to design constraints). Here we describe the acoustic and neural effects of cochlear and earphone distortion in the context of fMRI studies of pitch perception, and discuss how their effects can be minimized with appropriate stimuli and masking noise. The amplitude of cochlear and Sensimetrics earphone DPs were measured for a large collection of harmonic stimuli to assess effects of level, frequency, and waveform amplitude. Cochlear DP amplitudes were highly sensitive to the absolute frequency of the DP, and were most prominent at frequencies below 300 Hz. Cochlear DPs could thus be effectively masked by low-frequency noise, as expected. Earphone DP amplitudes, in contrast, were highly sensitive to both stimulus and DP frequency (due to prominent resonances in the earphone's transfer function), and their levels grew more rapidly with increasing stimulus level than did cochlear DP amplitudes. As a result, earphone DP amplitudes often exceeded those of cochlear DPs. Using fMRI, we found that earphone DPs had a substantial effect on the response of pitch-sensitive cortical regions. In contrast, cochlear DPs had a small effect on cortical fMRI responses that did not reach statistical significance, consistent with their lower amplitudes. Based on these findings, we designed a set of pitch stimuli optimized for identifying pitch-responsive brain regions using fMRI. These stimuli robustly drive pitch-responsive brain regions while producing minimal cochlear and earphone distortion, and will hopefully aid fMRI researchers in avoiding distortion confounds. Copyright © 2016 Elsevier Inc. All rights reserved.

Spoken language development in children following cochlear implantation.

PubMed

Niparko, John K; Tobey, Emily A; Thal, Donna J; Eisenberg, Laurie S; Wang, Nae-Yuh; Quittner, Alexandra L; Fink, Nancy E

2010-04-21

Cochlear implantation is a surgical alternative to traditional amplification (hearing aids) that can facilitate spoken language development in young children with severe to profound sensorineural hearing loss (SNHL). To prospectively assess spoken language acquisition following cochlear implantation in young children. Prospective, longitudinal, and multidimensional assessment of spoken language development over a 3-year period in children who underwent cochlear implantation before 5 years of age (n = 188) from 6 US centers and hearing children of similar ages (n = 97) from 2 preschools recruited between November 2002 and December 2004. Follow-up completed between November 2005 and May 2008. Performance on measures of spoken language comprehension and expression (Reynell Developmental Language Scales). Children undergoing cochlear implantation showed greater improvement in spoken language performance (10.4; 95% confidence interval [CI], 9.6-11.2 points per year in comprehension; 8.4; 95% CI, 7.8-9.0 in expression) than would be predicted by their preimplantation baseline scores (5.4; 95% CI, 4.1-6.7, comprehension; 5.8; 95% CI, 4.6-7.0, expression), although mean scores were not restored to age-appropriate levels after 3 years. Younger age at cochlear implantation was associated with significantly steeper rate increases in comprehension (1.1; 95% CI, 0.5-1.7 points per year younger) and expression (1.0; 95% CI, 0.6-1.5 points per year younger). Similarly, each 1-year shorter history of hearing deficit was associated with steeper rate increases in comprehension (0.8; 95% CI, 0.2-1.2 points per year shorter) and expression (0.6; 95% CI, 0.2-1.0 points per year shorter). In multivariable analyses, greater residual hearing prior to cochlear implantation, higher ratings of parent-child interactions, and higher socioeconomic status were associated with greater rates of improvement in comprehension and expression. The use of cochlear implants in young children was associated with better spoken language learning than would be predicted from their preimplantation scores.

Distortion Products in Auditory fMRI Research: Measurements and Solutions

PubMed Central

Norman-Haignere, Sam; McDermott, Josh H.

2016-01-01

Nonlinearities in the cochlea can introduce audio frequencies that are not present in the sound signal entering the ear. Known as distortion products (DPs), these added frequencies complicate the interpretation of auditory experiments. Sound production systems also introduce distortion via nonlinearities, a particular concern for fMRI research because the Sensimetrics earphones widely used for sound presentation are less linear than most high-end audio devices (due to design constraints). Here we describe the acoustic and neural effects of cochlear and earphone distortion in the context of fMRI studies of pitch perception, and discuss how their effects can be minimized with appropriate stimuli and masking noise. The amplitude of cochlear and Sensimetrics earphone DPs were measured for a large collection of harmonic stimuli to assess effects of level, frequency, and waveform amplitude. Cochlear DP amplitudes were highly sensitive to the absolute frequency of the DP, and were most prominent at frequencies below 300 Hz. Cochlear DPs could thus be effectively masked by low-frequency noise, as expected. Earphone DP amplitudes, in contrast, were highly sensitive to both stimulus and DP frequency (due to prominent resonances in the earphone’s transfer function), and their levels grew more rapidly with increasing stimulus level than did cochlear DP amplitudes. As a result, earphone DP amplitudes often exceeded those of cochlear DPs. Using fMRI, we found that earphone DPs had a substantial effect on the response of pitch-sensitive cortical regions. In contrast, cochlear DPs had a small effect on cortical fMRI responses that did not reach statistical significance, consistent with their lower amplitudes. Based on these findings, we designed a set of pitch stimuli optimized for identifying pitch-responsive brain regions using fMRI. These stimuli robustly drive pitch-responsive brain regions while producing minimal cochlear and earphone distortion, and will hopefully aid fMRI researchers in avoiding distortion confounds. PMID:26827809

Experiences from Auditory Brainstem Implantation (ABIs) in four paediatric patients.

PubMed

Lundin, Karin; Stillesjö, Fredrik; Nyberg, Gunnar; Rask-Andersen, Helge

2016-01-01

Indications for auditory brainstem implants (ABIs) have been widened from patients with neurofibromatosis type 2 (NF2) to paediatric patients with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, or cochlear ossification after meningitis. We present four ABI surgeries performed in children at Uppsala University Hospital in Sweden since 2009. Three children were implanted with implants from Cochlear Ltd. (Lane Cove, Australia) and one child with an implant from MedEl GMBH (Innsbruck, Austria). A boy with Goldenhar syndrome was implanted with a Cochlear Nucleus ABI24M at age 2 years (patient 1). Another boy with CHARGE syndrome was implanted with a Cochlear Nucleus ABI541 at age 2.5 years (patient 2). Another boy with post-ossification meningitis was implanted with a Cochlear Nucleus ABI24M at age 4 years (patient 3). A girl with cochlear aplasia was implanted with a MedEl Synchrony ABI at age 3 years (patient 4). In patients 1, 2, and 3, the trans-labyrinthine approach was used, and in patient 4 the retro-sigmoid approach was used. Three of the four children benefited from their ABIs and use it full time. Two of the full time users had categories of auditory performance (CAP) score of 4 at their last follow up visit (6 and 2.5 years postoperative) which means they can discriminate consistently any combination of two of Ling's sounds. One child has not been fully evaluated yet, but is a full time user and had CAP 2 (responds to speech sounds) after 3 months of ABI use. No severe side or unpleasant stimulation effects have been observed so far. There was one case of immediate electrode migration and one case of implant device failure after 6.5 years. ABI should be considered as an option in the rehabilitation of children with similar diagnoses.

The CAPOS mutation in ATP1A3 alters Na/K-ATPase function and results in auditory neuropathy which has implications for management.

PubMed

Tranebjærg, Lisbeth; Strenzke, Nicola; Lindholm, Sture; Rendtorff, Nanna D; Poulsen, Hanne; Khandelia, Himanshu; Kopec, Wojciech; Lyngbye, Troels J Brünnich; Hamel, Christian; Delettre, Cecile; Bocquet, Beatrice; Bille, Michael; Owen, Hanne H; Bek, Toke; Jensen, Hanne; Østergaard, Karen; Möller, Claes; Luxon, Linda; Carr, Lucinda; Wilson, Louise; Rajput, Kaukab; Sirimanna, Tony; Harrop-Griffiths, Katherine; Rahman, Shamima; Vona, Barbara; Doll, Julia; Haaf, Thomas; Bartsch, Oliver; Rosewich, Hendrik; Moser, Tobias; Bitner-Glindzicz, Maria

2018-02-01

Cerebellar ataxia, areflexia, pes cavus, optic atrophy and sensorineural hearing impairment (CAPOS) is a rare clinically distinct syndrome caused by a single dominant missense mutation, c.2452G>A, p.Glu818Lys, in ATP1A3, encoding the neuron-specific alpha subunit of the Na+/K+-ATPase α3. Allelic mutations cause the neurological diseases rapid dystonia Parkinsonism and alternating hemiplegia of childhood, disorders which do not encompass hearing or visual impairment. We present detailed clinical phenotypic information in 18 genetically confirmed patients from 11 families (10 previously unreported) from Denmark, Sweden, UK and Germany indicating a specific type of hearing impairment-auditory neuropathy (AN). All patients were clinically suspected of CAPOS and had hearing problems. In this retrospective analysis of audiological data, we show for the first time that cochlear outer hair cell activity was preserved as shown by the presence of otoacoustic emissions and cochlear microphonic potentials, but the auditory brainstem responses were grossly abnormal, likely reflecting neural dyssynchrony. Poor speech perception was observed, especially in noise, which was beyond the hearing level obtained in the pure tone audiograms in several of the patients presented here. Molecular modelling and in vitro electrophysiological studies of the specific CAPOS mutation were performed. Heterologous expression studies of α3 with the p.Glu818Lys mutation affects sodium binding to, and release from, the sodium-specific site in the pump, the third ion-binding site. Molecular dynamics simulations confirm that the structure of the C-terminal region is affected. In conclusion, we demonstrate for the first time evidence for auditory neuropathy in CAPOS syndrome, which may reflect impaired propagation of electrical impulses along the spiral ganglion neurons. This has implications for diagnosis and patient management. Auditory neuropathy is difficult to treat with conventional hearing aids, but preliminary improvement in speech perception in some patients suggests that cochlear implantation may be effective in CAPOS patients.

Cochlear implantation in adults with asymmetric hearing loss.

PubMed

Firszt, Jill B; Holden, Laura K; Reeder, Ruth M; Cowdrey, Lisa; King, Sarah

2012-01-01

Bilateral severe to profound sensorineural hearing loss is a standard criterion for cochlear implantation. Increasingly, patients are implanted in one ear and continue to use a hearing aid in the nonimplanted ear to improve abilities such as sound localization and speech understanding in noise. Patients with severe to profound hearing loss in one ear and a more moderate hearing loss in the other ear (i.e., asymmetric hearing) are not typically considered candidates for cochlear implantation. Amplification in the poorer ear is often unsuccessful because of limited benefit, restricting the patient to unilateral listening from the better ear alone. The purpose of this study was to determine whether patients with asymmetric hearing loss could benefit from cochlear implantation in the poorer ear with continued use of a hearing aid in the better ear. Ten adults with asymmetric hearing between ears participated. In the poorer ear, all participants met cochlear implant candidacy guidelines; seven had postlingual onset, and three had pre/perilingual onset of severe to profound hearing loss. All had open-set speech recognition in the better-hearing ear. Assessment measures included word and sentence recognition in quiet, sentence recognition in fixed noise (four-talker babble) and in diffuse restaurant noise using an adaptive procedure, localization of word stimuli, and a hearing handicap scale. Participants were evaluated preimplant with hearing aids and postimplant with the implant alone, the hearing aid alone in the better ear, and bimodally (the implant and hearing aid in combination). Postlingual participants were evaluated at 6 mo postimplant, and pre/perilingual participants were evaluated at 6 and 12 mo postimplant. Data analysis compared the following results: (1) the poorer-hearing ear preimplant (with hearing aid) and postimplant (with cochlear implant); (2) the device(s) used for everyday listening pre- and postimplant; and (3) the hearing aid-alone and bimodal listening conditions postimplant. The postlingual participants showed significant improvements in speech recognition after 6 mo cochlear implant use in the poorer ear. Five postlingual participants had a bimodal advantage over the hearing aid-alone condition on at least one test measure. On average, the postlingual participants had significantly improved localization with bimodal input compared with the hearing aid-alone. Only one pre/perilingual participant had open-set speech recognition with the cochlear implant. This participant had better hearing than the other two pre/perilingual participants in both the poorer and better ear. Localization abilities were not significantly different between the bimodal and hearing aid-alone conditions for the pre/perilingual participants. Mean hearing handicap ratings improved postimplant for all participants indicating perceived benefit in everyday life with the addition of the cochlear implant. Patients with asymmetric hearing loss who are not typical cochlear implant candidates can benefit from using a cochlear implant in the poorer ear with continued use of a hearing aid in the better ear. For this group of 10, the 7 postlingually deafened participants showed greater benefits with the cochlear implant than the pre/perilingual participants; however, further study is needed to determine maximum benefit for those with early onset of hearing loss.

Cochlear Implantation in Adults with Asymmetric Hearing Loss

PubMed Central

Firszt, Jill B.; Holden, Laura K.; Reeder, Ruth M.; Cowdrey, Lisa; King, Sarah

2012-01-01

Objective Bilateral severe-to-profound sensorineural hearing loss is a standard criterion for cochlear implantation. Increasingly, patients are implanted in one ear and continue to use a hearing aid in the non-implanted ear to improve abilities such as sound localization and speech understanding in noise. Patients with severe-to-profound hearing loss in one ear and a more moderate hearing loss in the other ear (i.e., asymmetric hearing) are not typically considered candidates for cochlear implantation. Amplification in the poorer ear is often unsuccessful due to limited benefit, restricting the patient to unilateral listening from the better ear alone. The purpose of this study was to determine if patients with asymmetric hearing loss could benefit from cochlear implantation in the poorer ear with continued use of a hearing aid in the better ear. Design Ten adults with asymmetric hearing between ears participated. In the poorer ear, all participants met cochlear implant candidacy guidelines; seven had postlingual onset and three had pre/perilingual onset of severe-to-profound hearing loss. All had open-set speech recognition in the better hearing ear. Assessment measures included word and sentence recognition in quiet, sentence recognition in fixed noise (four-talker babble) and in diffuse restaurant noise using an adaptive procedure, localization of word stimuli and a hearing handicap scale. Participants were evaluated pre-implant with hearing aids and post-implant with the implant alone, the hearing aid alone in the better ear and bimodally (the implant and hearing aid in combination). Postlingual participants were evaluated at six months post-implant and pre/perilingual participants were evaluated at six and 12 months post-implant. Data analysis compared results 1) of the poorer hearing ear pre-implant (with hearing aid) and post-implant (with cochlear implant), 2) with the device(s) used for everyday listening pre- and post-implant and, 3) between the hearing aid-alone and bimodal listening conditions post-implant. Results The postlingual participants showed significant improvements in speech recognition after six months cochlear implant use in the poorer ear. Five postlingual participants had a bimodal advantage over the hearing aid-alone condition on at least one test measure. On average, the postlingual participants had significantly improved localization with bimodal input compared to the hearing aid-alone. Only one pre/perilingual participant had open-set speech recognition with the cochlear implant. This participant had better hearing than the other two pre/perilingual participants in both the poorer and better ear. Localization abilities were not significantly different between the bimodal and hearing aid-alone conditions for the pre/perilingual participants. Mean hearing handicap ratings improved post-implant for all participants indicating perceived benefit in everyday life with the addition of the cochlear implant. Conclusions Patients with asymmetric hearing loss who are not typical cochlear implant candidates can benefit from using a cochlear implant in the poorer ear with continued use of a hearing aid in the better ear. For this group of ten, the seven postlingually deafened participants showed greater benefits with the cochlear implant than the pre/perilingual participants; however, further study is needed to determine maximum benefit for those with early onset of hearing loss. PMID:22441359

Speech perception for adult cochlear implant recipients in a realistic background noise: effectiveness of preprocessing strategies and external options for improving speech recognition in noise.

PubMed

Gifford, René H; Revit, Lawrence J

2010-01-01

Although cochlear implant patients are achieving increasingly higher levels of performance, speech perception in noise continues to be problematic. The newest generations of implant speech processors are equipped with preprocessing and/or external accessories that are purported to improve listening in noise. Most speech perception measures in the clinical setting, however, do not provide a close approximation to real-world listening environments. To assess speech perception for adult cochlear implant recipients in the presence of a realistic restaurant simulation generated by an eight-loudspeaker (R-SPACE) array in order to determine whether commercially available preprocessing strategies and/or external accessories yield improved sentence recognition in noise. Single-subject, repeated-measures design with two groups of participants: Advanced Bionics and Cochlear Corporation recipients. Thirty-four subjects, ranging in age from 18 to 90 yr (mean 54.5 yr), participated in this prospective study. Fourteen subjects were Advanced Bionics recipients, and 20 subjects were Cochlear Corporation recipients. Speech reception thresholds (SRTs) in semidiffuse restaurant noise originating from an eight-loudspeaker array were assessed with the subjects' preferred listening programs as well as with the addition of either Beam preprocessing (Cochlear Corporation) or the T-Mic accessory option (Advanced Bionics). In Experiment 1, adaptive SRTs with the Hearing in Noise Test sentences were obtained for all 34 subjects. For Cochlear Corporation recipients, SRTs were obtained with their preferred everyday listening program as well as with the addition of Focus preprocessing. For Advanced Bionics recipients, SRTs were obtained with the integrated behind-the-ear (BTE) mic as well as with the T-Mic. Statistical analysis using a repeated-measures analysis of variance (ANOVA) evaluated the effects of the preprocessing strategy or external accessory in reducing the SRT in noise. In addition, a standard t-test was run to evaluate effectiveness across manufacturer for improving the SRT in noise. In Experiment 2, 16 of the 20 Cochlear Corporation subjects were reassessed obtaining an SRT in noise using the manufacturer-suggested "Everyday," "Noise," and "Focus" preprocessing strategies. A repeated-measures ANOVA was employed to assess the effects of preprocessing. The primary findings were (i) both Noise and Focus preprocessing strategies (Cochlear Corporation) significantly improved the SRT in noise as compared to Everyday preprocessing, (ii) the T-Mic accessory option (Advanced Bionics) significantly improved the SRT as compared to the BTE mic, and (iii) Focus preprocessing and the T-Mic resulted in similar degrees of improvement that were not found to be significantly different from one another. Options available in current cochlear implant sound processors are able to significantly improve speech understanding in a realistic, semidiffuse noise with both Cochlear Corporation and Advanced Bionics systems. For Cochlear Corporation recipients, Focus preprocessing yields the best speech-recognition performance in a complex listening environment; however, it is recommended that Noise preprocessing be used as the new default for everyday listening environments to avoid the need for switching programs throughout the day. For Advanced Bionics recipients, the T-Mic offers significantly improved performance in noise and is recommended for everyday use in all listening environments. American Academy of Audiology.

Improving speech perception in noise for children with cochlear implants.

PubMed

Gifford, René H; Olund, Amy P; Dejong, Melissa

2011-10-01

Current cochlear implant recipients are achieving increasingly higher levels of speech recognition; however, the presence of background noise continues to significantly degrade speech understanding for even the best performers. Newer generation Nucleus cochlear implant sound processors can be programmed with SmartSound strategies that have been shown to improve speech understanding in noise for adult cochlear implant recipients. The applicability of these strategies for use in children, however, is not fully understood nor widely accepted. To assess speech perception for pediatric cochlear implant recipients in the presence of a realistic restaurant simulation generated by an eight-loudspeaker (R-SPACE™) array in order to determine whether Nucleus sound processor SmartSound strategies yield improved sentence recognition in noise for children who learn language through the implant. Single subject, repeated measures design. Twenty-two experimental subjects with cochlear implants (mean age 11.1 yr) and 25 control subjects with normal hearing (mean age 9.6 yr) participated in this prospective study. Speech reception thresholds (SRT) in semidiffuse restaurant noise originating from an eight-loudspeaker array were assessed with the experimental subjects' everyday program incorporating Adaptive Dynamic Range Optimization (ADRO) as well as with the addition of Autosensitivity control (ASC). Adaptive SRTs with the Hearing In Noise Test (HINT) sentences were obtained for all 22 experimental subjects, and performance-in percent correct-was assessed in a fixed +6 dB SNR (signal-to-noise ratio) for a six-subject subset. Statistical analysis using a repeated-measures analysis of variance (ANOVA) evaluated the effects of the SmartSound setting on the SRT in noise. The primary findings mirrored those reported previously with adult cochlear implant recipients in that the addition of ASC to ADRO significantly improved speech recognition in noise for pediatric cochlear implant recipients. The mean degree of improvement in the SRT with the addition of ASC to ADRO was 3.5 dB for a mean SRT of 10.9 dB SNR. Thus, despite the fact that these children have acquired auditory/oral speech and language through the use of their cochlear implant(s) equipped with ADRO, the addition of ASC significantly improved their ability to recognize speech in high levels of diffuse background noise. The mean SRT for the control subjects with normal hearing was 0.0 dB SNR. Given that the mean SRT for the experimental group was 10.9 dB SNR, despite the improvements in performance observed with the addition of ASC, cochlear implants still do not completely overcome the speech perception deficit encountered in noisy environments accompanying the diagnosis of severe-to-profound hearing loss. SmartSound strategies currently available in latest generation Nucleus cochlear implant sound processors are able to significantly improve speech understanding in a realistic, semidiffuse noise for pediatric cochlear implant recipients. Despite the reluctance of pediatric audiologists to utilize SmartSound settings for regular use, the results of the current study support the addition of ASC to ADRO for everyday listening environments to improve speech perception in a child's typical everyday program. American Academy of Audiology.

Multisensory training can promote or impede visual perceptual learning of speech stimuli: visual-tactile vs. visual-auditory training.

PubMed

Eberhardt, Silvio P; Auer, Edward T; Bernstein, Lynne E

2014-01-01

In a series of studies we have been investigating how multisensory training affects unisensory perceptual learning with speech stimuli. Previously, we reported that audiovisual (AV) training with speech stimuli can promote auditory-only (AO) perceptual learning in normal-hearing adults but can impede learning in congenitally deaf adults with late-acquired cochlear implants. Here, impeder and promoter effects were sought in normal-hearing adults who participated in lipreading training. In Experiment 1, visual-only (VO) training on paired associations between CVCVC nonsense word videos and nonsense pictures demonstrated that VO words could be learned to a high level of accuracy even by poor lipreaders. In Experiment 2, visual-auditory (VA) training in the same paradigm but with the addition of synchronous vocoded acoustic speech impeded VO learning of the stimuli in the paired-associates paradigm. In Experiment 3, the vocoded AO stimuli were shown to be less informative than the VO speech. Experiment 4 combined vibrotactile speech stimuli with the visual stimuli during training. Vibrotactile stimuli were shown to promote visual perceptual learning. In Experiment 5, no-training controls were used to show that training with visual speech carried over to consonant identification of untrained CVCVC stimuli but not to lipreading words in sentences. Across this and previous studies, multisensory training effects depended on the functional relationship between pathways engaged during training. Two principles are proposed to account for stimulus effects: (1) Stimuli presented to the trainee's primary perceptual pathway will impede learning by a lower-rank pathway. (2) Stimuli presented to the trainee's lower rank perceptual pathway will promote learning by a higher-rank pathway. The mechanisms supporting these principles are discussed in light of multisensory reverse hierarchy theory (RHT).

Multisensory training can promote or impede visual perceptual learning of speech stimuli: visual-tactile vs. visual-auditory training

PubMed Central

Eberhardt, Silvio P.; Auer Jr., Edward T.; Bernstein, Lynne E.

2014-01-01

In a series of studies we have been investigating how multisensory training affects unisensory perceptual learning with speech stimuli. Previously, we reported that audiovisual (AV) training with speech stimuli can promote auditory-only (AO) perceptual learning in normal-hearing adults but can impede learning in congenitally deaf adults with late-acquired cochlear implants. Here, impeder and promoter effects were sought in normal-hearing adults who participated in lipreading training. In Experiment 1, visual-only (VO) training on paired associations between CVCVC nonsense word videos and nonsense pictures demonstrated that VO words could be learned to a high level of accuracy even by poor lipreaders. In Experiment 2, visual-auditory (VA) training in the same paradigm but with the addition of synchronous vocoded acoustic speech impeded VO learning of the stimuli in the paired-associates paradigm. In Experiment 3, the vocoded AO stimuli were shown to be less informative than the VO speech. Experiment 4 combined vibrotactile speech stimuli with the visual stimuli during training. Vibrotactile stimuli were shown to promote visual perceptual learning. In Experiment 5, no-training controls were used to show that training with visual speech carried over to consonant identification of untrained CVCVC stimuli but not to lipreading words in sentences. Across this and previous studies, multisensory training effects depended on the functional relationship between pathways engaged during training. Two principles are proposed to account for stimulus effects: (1) Stimuli presented to the trainee’s primary perceptual pathway will impede learning by a lower-rank pathway. (2) Stimuli presented to the trainee’s lower rank perceptual pathway will promote learning by a higher-rank pathway. The mechanisms supporting these principles are discussed in light of multisensory reverse hierarchy theory (RHT). PMID:25400566

Progressive Susac syndrome with bilateral visual loss and disability.

PubMed

Entezari, Morteza; Karimi, Saeed; Feizi, Mohammadali

2016-09-01

Susac syndrome (SS) is a rare retinal-cochlear-cerebral disease with an unclear etiology. A 35-year-old man presented with sudden painless vision loss in the right eye and 2 months later in the left eye with hemiparesis, behavioral changes, and hearing loss. Ophthalmic examinations revealed multiple branch retinal artery occlusions (BRAOs) in both eyes. Brain magnetic resonance imaging showed inflammatory changes with multiple "punched-out" lesions in the corpus callosum which confirmed the diagnosis of SS. Despite intravenous and oral corticosteroid therapy, the disease progressed with the development of new BRAOs, low vision in both eyes, and disability. Prompt diagnosis and early treatment may save the vision and even patient's life.

A low-power noncoherent BPSK demodulator and clock recovery circuit for high-data-rate biomedical applications.

PubMed

Asgarian, Farzad; Sodagar, Amir M

2009-01-01

A novel noncoherent BPSK demodulator is presented for inductively powered biomedical devices. Differential Manchester encoding technique is used and data demodulation is based on pulse width measurement method. In addition to ultra low power consumption, high data rate without increasing the carrier frequency is achieved with the outstanding data-rate-to-carrier-frequency ratio of 100%. The proposed demodulator is especially appropriate for biomedical applications where high speed data transfer is required, e.g., cochlear implants and visual prostheses. The circuit is designed in a 0.18-mum standard CMOS technology and consumes as low as 232 microW@1.8V at a data rate of 10 Mbps.

Alternating Current Delivered into the Scala Media Alters Sound Pressure at the Eardrum

NASA Astrophysics Data System (ADS)

Hubbard, Allyn E.; Mountain, David C.

1983-11-01

Alternating current delivered into the scala media of the gerbil cochlea modulates the amplitude of a test tone measured near the eardrum. Variations in the electromechanical effect with acoustic stimulus parameters and observed physiological vulnerability suggest that cochlear hair cells are the biophysical origin of the process. Cochlear hair cells have traditionally been thought of as passive receptor cells, but they may play an active role in cochlear micromechanics.

Investigation of Notch Signaling during Spontaneous Regeneration of Cochlear Hair Cells

DTIC Science & Technology

2016-10-01

AWARD NUMBER: W81XWH-15-1-0475 TITLE: Investigation of Notch Signaling during Spontaneous Regeneration of Cochlear Hair Cells PRINCIPAL...Sep 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Investigation of Notch Signaling during Spontaneous Regeneration of Cochlear Hair Cells 5b...inherent to military settings. These noise exposures damage and kill sensory hair cells (HCs) found in the cochlea of the inner ear, resulting in permanent

In Vitro Studies and Preliminary Mathematical Model for Jet Fuel and Noise Induced Auditory Impairment

DTIC Science & Technology

2015-06-01

K.C. and Hu, B.H. 2006. The role of oxidative stress in noise-induced hearing loss. Ear Hear 27(1): 1-19. Hillerdal, M. 1987. Cochlear blood flow ...Larsen, H.C., Angelborg, C. and Slepecky, N. 1984. Determination of the regional cochlear blood flow in the rat cochlea using non-radioactive...24-Hour JP-8 Exposure using a Cochlear Cell Model and Cellular Pathway Modulation

Stanford Center for Military Photomedicine

DTIC Science & Technology

2014-09-08

cochlear implants after blast injury. A.2. WOUND HEALING. We have used several in vivo and in vitro models of wound healing to study the basic cell and...clinical information we will obtain has the potential to fundamentally alter the diagnosis and treatment of human cochlear pathology. Our microscope...of live guinea pigs, and have shown that FME can resolve cochlear structures in live subjects in a manner far superior to that of any other existing

Evaluation of Jet Fuel and Noise-Induced Hearing Loss in Rats (Rattus norvegicus)

DTIC Science & Technology

2014-05-13

product otoacoustic emissions (DPOAE) and compound action potential (CAP) testing of the cochlear nerve. Inner ear hair cell loss was also not affected...conclusion by revealing that exposure to JP-8 combined with noise may result in the loss of pre-neural cochlear sensitivity as shown by suppression of...distortion product otoacoustic emissions (DPOAE) and depletion of cochlear sensory cells as evidenced by cytocochleograms that plot the percentage of

Systemic Polyarteritis Nodosa as the Cause of Sudden Onset Bilateral Sensorineural Hearing Loss Following Lassa Virus Infection

DTIC Science & Technology

2016-07-05

occlusion of the anterior inferior cerebellar artery (AICA) and downstream vessels leading to cochlear hypoxia (18-24). Relevant to this work, PAN has...macaques showed moderate lymphoplasmacytic to chronic-active perivascular inflammation of the inner ear adjacent to the cochlear nerve The...inflammation occasionally surrounded smaller branches of the cochlear nerve, resembling pathological changes seen in humans diagnosed with PAN (Fig. 3B-E) (21

Cochlear Implantation in the Very Young Child: Issues Unique to the Under-1 Population

PubMed Central

Cosetti, Maura; Roland, J. Thomas

2010-01-01

Since the advent of cochlear implantation, candidacy criteria have slowly broadened to include increasingly younger patients. Spurred by evidence demonstrating both perioperative safety and significantly increased speech and language benefit with early auditory intervention, children younger than 12 months of age are now being successfully implanted at many centers. This review highlights the unique challenges involved in cochlear implantation in the very young child, specifically diagnosis and certainty of testing, anesthetic risk, surgical technique, intraoperative testing and postoperative programming, long-term safety, development of receptive and expressive language, and outcomes of speech perception. Overall, the current body of literature indicates that cochlear implantation prior to 1 year of age is both safe and efficacious. PMID:20483813

Visual servoing of a laser ablation based cochleostomy

NASA Astrophysics Data System (ADS)

Kahrs, Lüder A.; Raczkowsky, Jörg; Werner, Martin; Knapp, Felix B.; Mehrwald, Markus; Hering, Peter; Schipper, Jörg; Klenzner, Thomas; Wörn, Heinz

2008-03-01

The aim of this study is a defined, visually based and camera controlled bone removal by a navigated CO II laser on the promontory of the inner ear. A precise and minimally traumatic opening procedure of the cochlea for the implantation of a cochlear implant electrode (so-called cochleostomy) is intended. Harming the membrane linings of the inner ear can result in damage of remaining organ functions (e.g. complete deafness or vertigo). A precise tissue removal by a laser-based bone ablation system is investigated. Inside the borehole the pulsed laser beam is guided automatically over the bone by using a two mirror galvanometric scanner. The ablation process is controlled by visual servoing. For the detection of the boundary layers of the inner ear the ablation area is monitored by a color camera. The acquired pictures are analyzed by image processing. The results of this analysis are used to control the process of laser ablation. This publication describes the complete system including image processing algorithms and the concept for the resulting distribution of single laser pulses. The system has been tested on human cochleae in ex-vivo studies. Further developments could lead to safe intraoperative openings of the cochlea by a robot based surgical laser instrument.

Intraoperative Cochlear Implant Device Testing Utilizing an Automated Remote System: A Prospective Pilot Study.

PubMed

Lohmann, Amanda R; Carlson, Matthew L; Sladen, Douglas P

2018-03-01

Intraoperative cochlear implant device testing provides valuable information regarding device integrity, electrode position, and may assist with determining initial stimulation settings. Manual intraoperative device testing during cochlear implantation requires the time and expertise of a trained audiologist. The purpose of the current study is to investigate the feasibility of using automated remote intraoperative cochlear implant reverse telemetry testing as an alternative to standard testing. Prospective pilot study evaluating intraoperative remote automated impedance and Automatic Neural Response Telemetry (AutoNRT) testing in 34 consecutive cochlear implant surgeries using the Intraoperative Remote Assistant (Cochlear Nucleus CR120). In all cases, remote intraoperative device testing was performed by trained operating room staff. A comparison was made to the "gold standard" of manual testing by an experienced cochlear implant audiologist. Electrode position and absence of tip fold-over was confirmed using plain film x-ray. Automated remote reverse telemetry testing was successfully completed in all patients. Intraoperative x-ray demonstrated normal electrode position without tip fold-over. Average impedance values were significantly higher using standard testing versus CR120 remote testing (standard mean 10.7 kΩ, SD 1.2 vs. CR120 mean 7.5 kΩ, SD 0.7, p < 0.001). There was strong agreement between standard manual testing and remote automated testing with regard to the presence of open or short circuits along the array. There were, however, two cases in which standard testing identified an open circuit, when CR120 testing showed the circuit to be closed. Neural responses were successfully obtained in all patients using both systems. There was no difference in basal electrode responses (standard mean 195.0 μV, SD 14.10 vs. CR120 194.5 μV, SD 14.23; p = 0.7814); however, more favorable (lower μV amplitude) results were obtained with the remote automated system in the apical 10 electrodes (standard 185.4 μV, SD 11.69 vs. CR120 177.0 μV, SD 11.57; p value < 0.001). These preliminary data demonstrate that intraoperative cochlear implant device testing using a remote automated system is feasible. This system may be useful for cochlear implant programs with limited audiology support or for programs looking to streamline intraoperative device testing protocols. Future studies with larger patient enrollment are required to validate these promising, but preliminary, findings.

Tinnitus

MedlinePlus

... tinnitus in a significant number of study volunteers. Cochlear implants are sometimes used in people who have tinnitus along with severe hearing loss. A cochlear implant bypasses the damaged portion of the inner ...

Developmental Effects of Family Environment on Outcomes in Pediatric Cochlear Implant Recipients

PubMed Central

Holt, Rachael Frush; Beer, Jessica; Kronenberger, William G.; Pisoni, David B.

2012-01-01

Objective To examine and compare the family environment of preschool- and school-age children with cochlear implants and assess its influence on children’s executive function and spoken language skills. Study Design Retrospective between-subjects design. Setting Outpatient research laboratory. Patients Prelingually deaf children with cochlear implants and no additional disabilities, and their families. Intervention(s) Cochlear implantation and speech-language therapy. Main Outcome Measures Parents completed the Family Environment Scale and the Behavior Rating Inventory of Executive Function (or the preschool version). Children were tested using the Peabody Picture Vocabulary Test-4 and either the Preschool Language Scales-4 or the Clinical Evaluation of Language Fundamentals–4. Results The family environments of children with cochlear implants differed from normative data obtained from hearing children, but average scores were within one standard deviation of norms on all subscales. Families of school-age children reported higher levels of control than those of preschool-age children. Preschool-age children had fewer problems with emotional control when families reported higher levels of support and lower levels of conflict. School-age children had fewer problems with inhibition but more problems with shifting of attention when families reported lower levels of conflict. School-age children’s receptive vocabularies were enhanced by families with lower levels of control and higher levels of organization. Conclusions Family environment and its relation to language skills and executive function development differed across the age groups in this sample of children with cochlear implants. Because family dynamics is one developmental/environmental factor that can be altered with therapy and education, the present results have important clinical implications for family-based interventions for deaf children with cochlear implants. PMID:23151776

Development and evaluation of the Nurotron 26-electrode cochlear implant system.

PubMed

Zeng, Fan-Gang; Rebscher, Stephen J; Fu, Qian-Jie; Chen, Hongbin; Sun, Xiaoan; Yin, Li; Ping, Lichuan; Feng, Haihong; Yang, Shiming; Gong, Shusheng; Yang, Beibei; Kang, Hou-Yong; Gao, Na; Chi, Fanglu

2015-04-01

Although the cochlear implant has been widely acknowledged as the most successful neural prosthesis, only a fraction of hearing-impaired people who can potentially benefit from a cochlear implant have actually received one due to its limited awareness, accessibility, and affordability. To help overcome these limitations, a 26-electrode cochlear implant has been developed to receive China's Food and Drug Administration (CFDA) approval in 2011 and Conformité Européenne (CE) Marking in 2012. The present article describes design philosophy, system specification, and technical verification of the Nurotron device, which includes advanced digital signal processing and 4 current sources with multiple amplitude resolutions that not only are compatible with perceptual capability but also allow interleaved or simultaneous stimulation. The article also presents 3-year longitudinal evaluation data from 60 human subjects who have received the Nurotron device. The objective measures show that electrode impedance decreased within the first month of device use, but was stable until a slight increase at the end of two years. The subjective loudness measures show that electric stimulation threshold was stable while the maximal comfort level increased over the 3 years. Mandarin sentence recognition increased from the pre-surgical 0%-correct score to a plateau of about 80% correct with 6-month use of the device. Both indirect and direct comparisons indicate indistinguishable performance differences between the Nurotron system and other commercially available devices. The present 26-electrode cochlear implant has already helped to lower the price of cochlear implantation in China and will likely contribute to increased cochlear implant access and success in the rest of the world. This article is part of a Special Issue entitled . Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Across-site patterns of electrically evoked compound action potential amplitude-growth functions in multichannel cochlear implant recipients and the effects of the interphase gap.

PubMed

Schvartz-Leyzac, Kara C; Pfingst, Bryan E

2016-11-01

Electrically evoked compound action potential (ECAP) measures of peak amplitude, and amplitude-growth function (AGF) slope have been shown to reflect characteristics of cochlear health (primarily spiral ganglion density) in anesthetized cochlear-implanted guinea pigs. Likewise, the effect of increasing the interphase gap (IPG) in each of these measures also reflects SGN density in the implanted guinea pig. Based on these findings, we hypothesize that suprathreshold ECAP measures, and also how they change as the IPG is increased, have the potential to be clinically applicable in human subjects. However, further work is first needed in order to determine the characteristics of these measures in humans who use cochlear implants. The current study examined across-site patterns of suprathreshold ECAP measures in 10 bilaterally-implanted, adult cochlear implant users. Results showed that both peak amplitude and slope of the AGF varied significantly from electrode to electrode in ear-specific patterns across the subjects' electrode arrays. As expected, increasing the IPG on average increased the peak amplitude and slope. Across ears, there was a significant, negative correlation between the slope of the ECAP AGF and the duration of hearing loss. Across-site patterns of ECAP peak amplitude and AGF slopes were also compared with common ground impedance values and significant correlations were observed in some cases, depending on the subject and condition. The results of this study, coupled with previous studies in animals, suggest that it is feasible to measure the change in suprathreshold ECAP measures as the IPG increases on most electrodes. Further work is needed to investigate the relationship between these measures and cochlear implant outcomes, and determine how these measures might be used when programming a cochlear-implant processor. Published by Elsevier B.V.

The Effect of Cochlear Implantation on the Improvement of the Auditory Performance in 2-7 Years old Children, Shiraz 2004-2008.

PubMed

Hashemi, Sayed Basir; Rajaeefard, Abdolreza; Norouzpour, Hasan; Tabatabaee, Hamid Reza; Monshizadeh, Leila

2013-03-01

Hearing loss is the most common sensorineural deficiency in human beings. Cochlear implantation is introduced worldwide to treat the severe to profound sensorineural hearing loss, and can result in both speech comprehension and production. The present study aims to determine the effect of cochlear implantation on the improvement of the auditory performance in 2-7 years old children. The present follow-up study is a kind of cohort study which was conducted on 98 children between 2-7 years old who had referred to Fars Cochlear Implantation Center. The patients' information was gathered from their profiles both before and after the operation. The auditory performance score was obtained in 3 stages; 6 months, 1 year, and 2 years after the cochlear implantation through the Cap test. The data was analyzed using the nonparametric Friedman test as well as Mann-Withney, Kruskal-Wallis, and Spearman's Ranks Correlation coefficients. The mean and the median of the auditory performance score of the children who had undergone the cochlear implantation revealed a significant improvement from 6 months to 1 year, and 2 years after the implantation. It showed a significant statistical association between implantation age, type of hearing loss, regular reference, and the length of being present in the rehabilitation program with the auditory performance. It showed no significant association between sex, mother's level of education, being monolingual or bilingual, and family size with the auditory performance. This study revealed that the type of hearing loss, Presence in the rehabilitation program, and the age of cochlear implantation can be major prognostic factors of the response to the treatment, then the country's health policy makers and health planners must executively take into account the infants' hearing screening program during the first 6 month of age.

Auditory Cortex Basal Activity Modulates Cochlear Responses in Chinchillas

PubMed Central

León, Alex; Elgueda, Diego; Silva, María A.; Hamamé, Carlos M.; Delano, Paul H.

2012-01-01

Background The auditory efferent system has unique neuroanatomical pathways that connect the cerebral cortex with sensory receptor cells. Pyramidal neurons located in layers V and VI of the primary auditory cortex constitute descending projections to the thalamus, inferior colliculus, and even directly to the superior olivary complex and to the cochlear nucleus. Efferent pathways are connected to the cochlear receptor by the olivocochlear system, which innervates outer hair cells and auditory nerve fibers. The functional role of the cortico-olivocochlear efferent system remains debated. We hypothesized that auditory cortex basal activity modulates cochlear and auditory-nerve afferent responses through the efferent system. Methodology/Principal Findings Cochlear microphonics (CM), auditory-nerve compound action potentials (CAP) and auditory cortex evoked potentials (ACEP) were recorded in twenty anesthetized chinchillas, before, during and after auditory cortex deactivation by two methods: lidocaine microinjections or cortical cooling with cryoloops. Auditory cortex deactivation induced a transient reduction in ACEP amplitudes in fifteen animals (deactivation experiments) and a permanent reduction in five chinchillas (lesion experiments). We found significant changes in the amplitude of CM in both types of experiments, being the most common effect a CM decrease found in fifteen animals. Concomitantly to CM amplitude changes, we found CAP increases in seven chinchillas and CAP reductions in thirteen animals. Although ACEP amplitudes were completely recovered after ninety minutes in deactivation experiments, only partial recovery was observed in the magnitudes of cochlear responses. Conclusions/Significance These results show that blocking ongoing auditory cortex activity modulates CM and CAP responses, demonstrating that cortico-olivocochlear circuits regulate auditory nerve and cochlear responses through a basal efferent tone. The diversity of the obtained effects suggests that there are at least two functional pathways from the auditory cortex to the cochlea. PMID:22558383

Noise alters hair-bundle mechanics at the cochlear apex

NASA Astrophysics Data System (ADS)

Strimbu, C. Elliott; Fridberger, Anders

2015-12-01

Exposure to loud sounds can lead to both permanent and short term changes in auditory sensitivity. Permanent hearing loss is often associated with gross changes in cochlear morphology including the loss of hair cells and auditory nerve fibers while the mechanisms of short term threshold shifts are much less well understood and may vary at different locations across the cochlea. Previous reports suggest that exposure to loud sounds leads to a decrease in the cochlear microphonic potential and in the stiffness of the organ of Corti. Because the cochlear microphonic reflects changes in the membrane potential of the hair cells, this suggests that hair-bundle motion should be reversibly altered following exposure to loud sounds. Using an in vitro preparation of the guinea pig temporal bone we investigate changes in the micro-mechanical response near the cochlear apex following a brief (up to 10 - 20 minutes) exposure to loud (˜ 120 dB) tones near the best frequency at this location. We use time-resolved confocal imaging to record the motion of outer hair cell bundles before and after acoustic overstimulation. We have also recorded larger-scale structural views of the organ of Corti before and after exposure to the loud sound. Conventional electrophysiological techniques are used measure the cochlear microphonic potential. As has been previously reported, following acoustic overexposure the cochlear microphonic declines in value and typically recovers on the order of 30 - 60 minutes. Hair-bundle trajectories are affected following the loud sound and typically recover on a somewhat faster time scale than the microphonic potential, although the results vary considerably across preparations. Preliminary results also suggest reversible changes in the hair cell's resting potential following the loud sound.

Factors influencing the efficacy of round window dexamethasone protection of residual hearing post-cochlear implant surgery.

PubMed

Chang, Andrew; Eastwood, Hayden; Sly, David; James, David; Richardson, Rachael; O'Leary, Stephen

2009-09-01

To protect hearing in an experimental model of cochlear implantation by the application of dexamethasone to the round window prior to surgery. The present study examined the dosage and timing relationships required to optimise the hearing protection. Dexamethasone or saline (control) was absorbed into a pledget of the carboxymethylcellulose and hyaluronic acid and applied to the round window of the guinea pig prior to cochlear implantation. The treatment groups were 2% w/v dexamethasone for 30, 60 and 120min; 20% dexamethasone applied for 30min. Auditory sensitivity was determined pre-operatively, and at 1 week after surgery, with pure-tone auditory brainstem response audiometry (2-32kHz). Cochlear implantation was performed via a cochleostomy drilled into the basal turn of the cochlea, into which a miniature cochlear implant dummy electrode was inserted using soft-surgery techniques. ABR thresholds were elevated after cochlear implantation, maximally at 32kHz and to a lesser extent at lower frequencies. Thresholds were less elevated after dexamethasone treatment, and the hearing protection improved when 2% dexamethasone was applied to the round window for longer periods of time prior to implantation. The time that dexamethasone need be applied to achieve hearing protection could be reduced by increasing the concentration of steroid, with a 20% application for 30min achieving similar levels of protection to a 60min application of 2% dexamethasone. Hearing protection is improved by increasing the time that dexamethasone is applied to the round window prior to cochlear implantation, and the waiting time can be reduced by increasing the steroid concentration. These results suggest that the diffusion dexamethasone through the cochlea is the prime determinant of the extent of hearing protection.

The impact of cochlear implantation on speech understanding, subjective hearing performance, and tinnitus perception in patients with unilateral severe to profound hearing loss.

PubMed

Távora-Vieira, Dayse; Marino, Roberta; Acharya, Aanand; Rajan, Gunesh P

2015-03-01

This study aimed to determine the impact of cochlear implantation on speech understanding in noise, subjective perception of hearing, and tinnitus perception of adult patients with unilateral severe to profound hearing loss and to investigate whether duration of deafness and age at implantation would influence the outcomes. In addition, this article describes the auditory training protocol used for unilaterally deaf patients. This is a prospective study of subjects undergoing cochlear implantation for unilateral deafness with or without associated tinnitus. Speech perception in noise was tested using the Bamford-Kowal-Bench speech-in-noise test presented at 65 dB SPL. The Speech, Spatial, and Qualities of Hearing Scale and the Abbreviated Profile of Hearing Aid Benefit were used to evaluate the subjective perception of hearing with a cochlear implant and quality of life. Tinnitus disturbance was measured using the Tinnitus Reaction Questionnaire. Data were collected before cochlear implantation and 3, 6, 12, and 24 months after implantation. Twenty-eight postlingual unilaterally deaf adults with or without tinnitus were implanted. There was a significant improvement in speech perception in noise across time in all spatial configurations. There was an overall significant improvement on the subjective perception of hearing and quality of life. Tinnitus disturbance reduced significantly across time. Age at implantation and duration of deafness did not influence the outcomes significantly. Cochlear implantation provided significant improvement in speech understanding in challenging situations, subjective perception of hearing performance, and quality of life. Cochlear implantation also resulted in reduced tinnitus disturbance. Age at implantation and duration of deafness did not seem to influence the outcomes.

The Role of the World Health Organization's International Classification of Functioning, Health and Disability in Models of Infant Cochlear Implant Management

PubMed Central

Psarros, Colleen; Love, Sarah

2016-01-01

Newborn hearing screening has led to the early diagnosis of hearing loss in neonates and early device fitting is common, based primarily on electrophysiologic and radiologic information, with some supplementary behavioral measures. Such early fitting of hearing devices, in particular cochlear implants (CIs), has been beneficial to the majority of children implanted under the age of 12 months who meet the cochlear implant candidacy criteria. Comorbidities are common in children with hearing loss, although they may not be evident in neonates and may not emerge until later in infants. Evidence suggests that the child's outcomes are strongly influenced by a range of environmental factors including emotional and social support from the immediate and extended family. Consequently, such factors are important in service planning and service delivery for babies and children receiving CIs. The World Health Organization's International Classification of Functioning, Health and Disability (ICF) can provide a framework to facilitate the holistic management of pediatric cochlear implant recipients. The ICF also can be used to map the progress of recipients over time to highlight emerging issues that require intervention. This article will discuss our preliminary use of the ICF to establish clinical practice; develop advocacy skills among clients and their families; identify eligibility for services such as support in educational settings; enable access to modes of service delivery such as telepractice; provide a conceptual framework for policy and program development for pediatric cochlear implant recipients (i.e., in both disability and health services); and, most importantly, establish a clear pathway for the longitudinal management of the cochlear implant in a child's future. It is anticipated that this model will be applied to other populations receiving cochlear implants through our program. PMID:27489404

Developmental and cross-modal plasticity in deafness: evidence from the P1 and N1 event related potentials in cochlear implanted children.

PubMed

Sharma, Anu; Campbell, Julia; Cardon, Garrett

2015-02-01

Cortical development is dependent on extrinsic stimulation. As such, sensory deprivation, as in congenital deafness, can dramatically alter functional connectivity and growth in the auditory system. Cochlear implants ameliorate deprivation-induced delays in maturation by directly stimulating the central nervous system, and thereby restoring auditory input. The scenario in which hearing is lost due to deafness and then reestablished via a cochlear implant provides a window into the development of the central auditory system. Converging evidence from electrophysiologic and brain imaging studies of deaf animals and children fitted with cochlear implants has allowed us to elucidate the details of the time course for auditory cortical maturation under conditions of deprivation. Here, we review how the P1 cortical auditory evoked potential (CAEP) provides useful insight into sensitive period cut-offs for development of the primary auditory cortex in deaf children fitted with cochlear implants. Additionally, we present new data on similar sensitive period dynamics in higher-order auditory cortices, as measured by the N1 CAEP in cochlear implant recipients. Furthermore, cortical re-organization, secondary to sensory deprivation, may take the form of compensatory cross-modal plasticity. We provide new case-study evidence that cross-modal re-organization, in which intact sensory modalities (i.e., vision and somatosensation) recruit cortical regions associated with deficient sensory modalities (i.e., auditory) in cochlear implanted children may influence their behavioral outcomes with the implant. Improvements in our understanding of developmental neuroplasticity in the auditory system should lead to harnessing central auditory plasticity for superior clinical technique. Copyright © 2014 Elsevier B.V. All rights reserved.

Will They Catch Up? The Role of Age at Cochlear Implantation in the Spoken Language Development of Children with Severe to Profound Hearing Loss

ERIC Educational Resources Information Center

Nicholas, Johanna Grant; Geers, Ann E.

2007-01-01

Purpose: The authors examined the benefits of younger cochlear implantation, longer cochlear implant use, and greater pre-implant aided hearing to spoken language at 3.5 and 4.5 years of age. Method: Language samples were obtained at ages 3.5 and 4.5 years from 76 children who received an implant by their 3rd birthday. Hierarchical linear modeling…

Biomechanical Modeling and Measurement of Blast Injury and Hearing Protection Mechanisms

DTIC Science & Technology

2015-10-01

12 software into Workbench V. 15 in CFX/ANSYS; 2) building the geometry of the ear model with ossicular chain and cochlear load in CFX; 3...the ear canal to middle ear. The model consists of the ear canal, TM, middle ear ossicles and suspensory ligaments, middle ear cavity, and cochlear ...the TM, ossicles, and ligaments/muscle tendons with the cochlear load applied on the stapes footplate. 17 Fig. 21. Time-history plots of

Sensory-motor relationships in speech production in post-lingually deaf cochlear-implanted adults and normal-hearing seniors: Evidence from phonetic convergence and speech imitation.

PubMed

Scarbel, Lucie; Beautemps, Denis; Schwartz, Jean-Luc; Sato, Marc

2017-07-01

Speech communication can be viewed as an interactive process involving a functional coupling between sensory and motor systems. One striking example comes from phonetic convergence, when speakers automatically tend to mimic their interlocutor's speech during communicative interaction. The goal of this study was to investigate sensory-motor linkage in speech production in postlingually deaf cochlear implanted participants and normal hearing elderly adults through phonetic convergence and imitation. To this aim, two vowel production tasks, with or without instruction to imitate an acoustic vowel, were proposed to three groups of young adults with normal hearing, elderly adults with normal hearing and post-lingually deaf cochlear-implanted patients. Measure of the deviation of each participant's f 0 from their own mean f 0 was measured to evaluate the ability to converge to each acoustic target. showed that cochlear-implanted participants have the ability to converge to an acoustic target, both intentionally and unintentionally, albeit with a lower degree than young and elderly participants with normal hearing. By providing evidence for phonetic convergence and speech imitation, these results suggest that, as in young adults, perceptuo-motor relationships are efficient in elderly adults with normal hearing and that cochlear-implanted adults recovered significant perceptuo-motor abilities following cochlear implantation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Breaking the sound barrier: exploring parents' decision-making process of cochlear implants for their children.

PubMed

Chang, Pamara F

2017-08-01

To understand the dynamic experiences of parents undergoing the decision-making process regarding cochlear implants for their child(ren). Thirty-three parents of d/Deaf children participated in semi-structured interviews. Interviews were digitally recorded, transcribed, and coded using iterative and thematic coding. The results from this study reveal four salient topics related to parents' decision-making process regarding cochlear implantation: 1) factors parents considered when making the decision to get the cochlear implant for their child (e.g., desire to acculturate child into one community), 2) the extent to which parents' communities influence their decision-making (e.g., norms), 3) information sources parents seek and value when decision-making (e.g., parents value other parent's experiences the most compared to medical or online sources), and 4) personal experiences with stigma affecting their decision to not get the cochlear implant for their child. This study provides insights into values and perspectives that can be utilized to improve informed decision-making, when making risky medical decisions with long-term implications. With thorough information provisions, delineation of addressing parents' concerns and encompassing all aspects of the decision (i.e., medical, social and cultural), health professional teams could reduce the uncertainty and anxiety for parents in this decision-making process for cochlear implantation. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing the immunization status of pediatric cochlear implant recipients using a state-maintained immunization registry.

PubMed

Ou, Henry; Cleary, Patricia; Sie, Kathleen

2010-10-01

To demonstrate the use of a state-maintained database (CHILD Profile) to monitor immunization status of pediatric cochlear implant recipients, and to assess compliance with current vaccination recommendations for cochlear implant users managed at Seattle Children's Hospital. Cross-sectional study. Tertiary academic pediatric hospital. Subjects were 260 patients with cochlear implants managed at Seattle Children's Hospital between July 1, 1995, and May 1, 2008. Patients were stratified by age groups (0-2 years, 2-5 years, 5-10 years, > 10 years). Using a statewide children's immunization registry (CHILD Profile), subjects were assessed with regard to their immunization status for Haemophilus influenzae type B vaccination (HiB), 7-valent pneumococcal conjugate vaccination (PCV-7), and 23-valent pneumococcal polysaccharide vaccine (PPV-23). Two hundred twenty-five of 260 subjects (87%) were registered in CHILD Profile; 126 of 225 (56%) were up to date with CDC recommendations for patients with cochlear implants. PPV-23 was the vaccination most likely to be incomplete. Age was predictive of immunization status only with HiB vaccination. A statewide immunization registry can be used to monitor the immunization status of cochlear implant recipients. Subjects were significantly more likely to be incomplete for PPV-23 than for either PCV-7 or HiB vaccinations. Copyright © 2010 American Academy of Otolaryngology–Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

Noise-induced cochlear synaptopathy: Past findings and future studies.

PubMed

Kobel, Megan; Le Prell, Colleen G; Liu, Jennifer; Hawks, John W; Bao, Jianxin

2017-06-01

For decades, we have presumed the death of hair cells and spiral ganglion neurons are the main cause of hearing loss and difficulties understanding speech in noise, but new findings suggest synapse loss may be the key contributor. Specifically, recent preclinical studies suggest that the synapses between inner hair cells and spiral ganglion neurons with low spontaneous rates and high thresholds are the most vulnerable subcellular structures, with respect to insults during aging and noise exposure. This cochlear synaptopathy can be "hidden" because this synaptic loss can occur without permanent hearing threshold shifts. This new discovery of synaptic loss opens doors to new research directions. Here, we review a number of recent studies and make suggestions in two critical future research directions. First, based on solid evidence of cochlear synaptopathy in animal models, it is time to apply molecular approaches to identify the underlying molecular mechanisms; improved understanding is necessary for developing rational, effective therapies against this cochlear synaptopathy. Second, in human studies, the data supporting cochlear synaptopathy are indirect although rapid progress has been made. To fully identify changes in function that are directly related this hidden synaptic damage, we argue that a battery of tests including both electrophysiological and behavior tests should be combined for diagnosis of "hidden hearing loss" in clinical studies. This new approach may provide a direct link between cochlear synaptopathy and perceptual difficulties. Copyright © 2016 Elsevier B.V. All rights reserved.

Relationship between auditory perception and vocal production in cochlear implantees: a systematic review.

PubMed

Cysneiros, Helena Renata Silva; Leal, Mariana de Carvalho; Lucena, Jonia Alves; Muniz, Lilian Ferreira

To conduct a systematic review of the scientific literature studying the relationship between vocal production and auditory perception in cochlear implant users. This is an integrative systematic review. The plattforms/databases Bireme, SciELO, Cochrane, Scopus and Web of Science were consulted and the descriptors used were voice, cochlear implant and auditory perception. Original papers published in English, French, Spanish or Portuguese involving the study of vocal production and auditory perception in cochlear implant users were selected and there was no restriction about year of publication of the articles. The studies selected were analyzed according to the author, location, year and publication of the article, as well as for their sample size, type of vocal production and auditory perception assessment and for its major findings and recommendation grade/level of scientific evidence. The results suggest the existence of positive relationship between vocal production and auditory perception in cochlear implant users, and indicate that the deployment time has a positive influence in this relationship. None of the selected studies were rated at level 1 of scientific evidence or grade A of recommendation, which is related to the methodological approach that can go with this subject matter. There is great lack of publications relating auditory perception and speech production in cochlear implant users. This gap is even greater when it comes to the adult population.

Analysis of electrically evoked compound action potential of the auditory nerve in children with bilateral cochlear implants.

PubMed

Caldas, Fernanda Ferreira; Cardoso, Carolina Costa; Barreto, Monique Antunes de Souza Chelminski; Teixeira, Marina Santos; Hilgenberg, Anacléia Melo da Silva; Serra, Lucieny Silva Martins; Bahmad Junior, Fayez

2016-01-01

The cochlear implant device has the capacity to measure the electrically evoked compound action potential of the auditory nerve. The neural response telemetry is used in order to measure the electrically evoked compound action potential of the auditory nerve. To analyze the electrically evoked compound action potential, through the neural response telemetry, in children with bilateral cochlear implants. This is an analytical, prospective, longitudinal, historical cohort study. Six children, aged 1-4 years, with bilateral cochlear implant were assessed at five different intervals during their first year of cochlear implant use. There were significant differences in follow-up time (p=0.0082) and electrode position (p=0.0019) in the T-NRT measure. There was a significant difference in the interaction between time of follow-up and electrode position (p=0.0143) when measuring the N1-P1 wave amplitude between the three electrodes at each time of follow-up. The electrically evoked compound action potential measurement using neural response telemetry in children with bilateral cochlear implants during the first year of follow-up was effective in demonstrating the synchronized bilateral development of the peripheral auditory pathways in the studied population. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Variation analysis of transcriptome changes reveals cochlear genes and their associated functions in cochlear susceptibility to acoustic overstimulation.

PubMed

Yang, Shuzhi; Cai, Qunfeng; Bard, Jonathan; Jamison, Jennifer; Wang, Jianmin; Yang, Weiping; Hu, Bo Hua

2015-12-01

Individual variation in the susceptibility of the auditory system to acoustic overstimulation has been well-documented at both the functional and structural levels. However, the molecular mechanism responsible for this variation is unclear. The current investigation was designed to examine the variation patterns of cochlear gene expression using RNA-seq data and to identify the genes with expression variation that increased following acoustic trauma. This study revealed that the constitutive expressions of cochlear genes displayed diverse levels of gene-specific variation. These variation patterns were altered by acoustic trauma; approximately one-third of the examined genes displayed marked increases in their expression variation. Bioinformatics analyses revealed that the genes that exhibited increased variation were functionally related to cell death, biomolecule metabolism, and membrane function. In contrast, the stable genes were primarily related to basic cellular processes, including protein and macromolecular syntheses and transport. There was no functional overlap between the stable and variable genes. Importantly, we demonstrated that glutamate metabolism is related to the variation in the functional response of the cochlea to acoustic overstimulation. Taken together, the results indicate that our analyses of the individual variations in transcriptome changes of cochlear genes provide important information for the identification of genes that potentially contribute to the generation of individual variation in cochlear responses to acoustic overstimulation. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of cochlear implantation in development of intelligence quotient of 6-9 deaf children in comparison with normal hearing children (Iran, 2009-2011).

PubMed

Hashemi, Seyed Basir; Monshizadeh, Leila

2012-06-01

Before the introduction of cochlear implant (CI) in 1980, hearing aids were the only means by which profoundly deaf children had access to auditory stimuli. Nowadays, CI is firmly established as effective option in speech and language rehabilitation of deaf children, but much of the literature regarding outcomes for children after CI are focused on development of speech and less is known about language acquisition. So, the main aim of this study is the evaluation of verbal intelligence quotient (IQ) of cochlear implanted children in comparison with normal children. 30 cochlear implanted and 30 normal hearing children with similar socio-economic level at the same age were compared by a revised version (in Persian) of WISC test (Wechsler, 1991). Then the data were analyzed through SPSS software 16. In spite of the fact that cochlear implanted children did well in different parameters of WISC test, the average scores of this group was less than normal hearing children. But in similarities (one of the parameters of WISC test) 2 group's performance was approximately the same. CI plays an important role in development of verbal IQ and language acquisition of deaf children. Different researches indicate that most of the cochlear implanted children show less language delay during the time. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Contribution of Family Environment to Pediatric Cochlear Implant Users’ Speech and Language Outcomes: Some Preliminary Findings

PubMed Central

Holt, Rachael Frush; Beer, Jessica; Kronenberger, William G.; Pisoni, David B.; Lalonde, Kaylah

2012-01-01

Purpose To evaluate the family environments of children with cochlear implants and to examine relationships between family environment and post-implant language development and executive function. Method Forty-five families of children with cochlear implants completed a self-report family environment questionnaire (FES) and an inventory of executive function (BRIEF/BRIEF-P). Children’s receptive vocabulary (PPVT-4) and global language skills (PLS-4/CELF-4) were also evaluated. Results The family environments of children with cochlear implants differed from those of normal-hearing children, but not in clinically significant ways. Language development and executive function were found to be atypical, but not uncharacteristic of this clinical population. Families with higher levels of self-reported control had children with smaller vocabularies. Families reporting a higher emphasis on achievement had children with fewer executive function and working memory problems. Finally, families reporting a higher emphasis on organization had children with fewer problems related to inhibition. Conclusions Some of the variability in cochlear implantation outcomes that have protracted periods of development is related to family environment. Because family environment can be modified and enhanced by therapy or education, these preliminary findings hold promise for future work in helping families to create robust language-learning environments that can maximize their child’s potential with a cochlear implant. PMID:22232387

Etanercept prevents decrease of cochlear blood flow dose-dependently caused by tumor necrosis factor alpha.

PubMed

Ihler, Friedrich; Sharaf, Kariem; Bertlich, Mattis; Strieth, Sebastian; Reichel, Christoph A; Berghaus, Alexander; Canis, Martin

2013-07-01

Tumor necrosis factor alpha (TNF-alpha) is a mediator of inflammation and microcirculation in the cochlea. This study aimed to quantify the effect of a local increase of TNF-alpha and study the effect of its interaction with etanercept on cochlear microcirculation. Cochlear lateral wall vessels were exposed surgically and assessed by intravital microscopy in guinea pigs in vivo. First, 24 animals were randomly distributed into 4 groups of 6 each. Exposed vessels were superfused repeatedly either with 1 of 3 different concentrations of TNF-alpha (5.0, 0.5, and 0.05 ng/mL) or with placebo (0.9% saline solution). Second, 12 animals were randomly distributed into 2 groups of 6 each. Vessels were pretreated with etanercept (1.0 microg/ mL) or placebo (0.9% saline solution), and then treated by repeated superfusion with TNF-alpha (5.0 ng/mL). TNF-alpha was shown to be effective in decreasing cochlear blood flow at a dose of 5.0 ng/mL (p < 0.01, analysis of variance on ranks). Lower concentrations or placebo treatment did not lead to significant changes. After pretreatment with etanercept, TNF-alpha at a dose of 5.0 ng/mL no longer led to a change in cochlear blood flow. The decreasing effect that TNF-alpha has on cochlear blood flow is dose-dependent. Etanercept abrogates this effect.

Noise reduction technologies implemented in head-worn preprocessors for improving cochlear implant performance in reverberant noise fields.

PubMed

Chung, King; Nelson, Lance; Teske, Melissa

2012-09-01

The purpose of this study was to investigate whether a multichannel adaptive directional microphone and a modulation-based noise reduction algorithm could enhance cochlear implant performance in reverberant noise fields. A hearing aid was modified to output electrical signals (ePreprocessor) and a cochlear implant speech processor was modified to receive electrical signals (eProcessor). The ePreprocessor was programmed to flat frequency response and linear amplification. Cochlear implant listeners wore the ePreprocessor-eProcessor system in three reverberant noise fields: 1) one noise source with variable locations; 2) three noise sources with variable locations; and 3) eight evenly spaced noise sources from 0° to 360°. Listeners' speech recognition scores were tested when the ePreprocessor was programmed to omnidirectional microphone (OMNI), omnidirectional microphone plus noise reduction algorithm (OMNI + NR), and adaptive directional microphone plus noise reduction algorithm (ADM + NR). They were also tested with their own cochlear implant speech processor (CI_OMNI) in the three noise fields. Additionally, listeners rated overall sound quality preferences on recordings made in the noise fields. Results indicated that ADM+NR produced the highest speech recognition scores and the most preferable rating in all noise fields. Factors requiring attention in the hearing aid-cochlear implant integration process are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

Feed-forward and feed-backward amplification model from cochlear cytoarchitecture: an interspecies comparison.

PubMed

Yoon, Yong-Jin; Steele, Charles R; Puria, Sunil

2011-01-05

The high sensitivity and wide bandwidth of mammalian hearing are thought to derive from an active process involving the somatic and hair-bundle motility of the thousands of outer hair cells uniquely found in mammalian cochleae. To better understand this, a biophysical three-dimensional cochlear fluid model was developed for gerbil, chinchilla, cat, and human, featuring an active "push-pull" cochlear amplifier mechanism based on the cytoarchitecture of the organ of Corti and using the time-averaged Lagrangian method. Cochlear responses are simulated and compared with in vivo physiological measurements for the basilar membrane (BM) velocity, V(BM), frequency tuning of the BM vibration, and Q₁₀ values representing the sharpness of the cochlear tuning curves. The V(BM) simulation results for gerbil and chinchilla are consistent with in vivo cochlea measurements. Simulated mechanical tuning curves based on maintaining a constant V(BM) value agree with neural-tuning threshold measurements better than those based on a constant displacement value, which implies that the inner hair cells are more sensitive to V(BM) than to BM displacement. The Q₁₀ values of the V(BM) tuning curve agree well with those of cochlear neurons across species, and appear to be related in part to the width of the basilar membrane. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Outcomes and special considerations of cochlear implantation in waardenburg syndrome.

PubMed

Kontorinis, Georgios; Lenarz, Thomas; Giourgas, Alexandros; Durisin, Martin; Lesinski-Schiedat, Anke

2011-08-01

The objective of this study was a state-of-the-art analysis of cochlear implantation in patients with Waardenburg syndrome (WS). Twenty-five patients with WS treated with cochlear implants in our department from 1990 to 2010. The 25 patients with WS underwent 35 cochlear implantations. Hearing outcome was evaluated using HSM sentence test in 65 dB in quiet, Freiburg Monosyllabic Test, and categories of auditory performance for children and compared with that of a control group. Anatomic abnormalities of the inner ear were examined using magnetic resonance imaging and computed tomography of the temporal bones. The mean follow-up time was 8.3 years (range, 0.3-18.3 yr). The majority achieved favorable postimplantation performance with mean HSM scores of 75.3% (range, 22.6%-99%) and Freiburg Monosyllabic Test scores of 67.8% (range, 14%-95%). However, in 4 cases, the results were less satisfactory. The comparison with the control group did not reveal any statistical significance (p = 0.56). In 6 patients (24%), behavioral disorders caused temporary difficulties during the rehabilitation procedure. Except of isolated large vestibule in 1 patient, the radiological assessment of the 50 temporal bones did not reveal any temporal bone abnormalities. Most patients with WS performed well with cochlear implants. However, WS is related to behavioral disorders that may cause temporary rehabilitation difficulties. Finally, temporal bone malformations that could affect cochlear implantation are notcharacteristic of WS.

Profound hearing loss associated with hydrocodone/acetaminophen abuse.

PubMed

Friedman, R A; House, J W; Luxford, W M; Gherini, S; Mills, D

2000-03-01

To describe profound hearing loss associated with hydrocodone overuse and the successful rehabilitation of these patients with cochlear implantation. Retrospective review. A tertiary otologic referral center. Twelve patients with rapidly progressive hearing loss and a concurrent history of hydrocodone overuse. Comprehensive medical histories, physical findings, audiometric tests, and, in those patients undergoing cochlear implantation, postimplantation performance data were reviewed. Clinical characteristics of hydrocodone-related hearing loss and open set word and sentence performance in those patients undergoing cochlear implantation. Hydrocodone overuse was associated with rapidly progressive sensorineural hearing loss in 12 patients. In four patients the initial presentation was unilateral, and two of the patients experienced vestibular symptoms. None of the 12 patients experienced improved thresholds after high-dose prednisone. Seven of the eight patients undergoing cochlear implantation have demonstrated early success with their devices. Hydrocodone is frequently prescribed in combination with acetaminophen for the relief of pain and has a side effects profile similar to other medications in its class. Although not described previously, overuse or abuse can be associated with a rapidly progressive sensorineural hearing loss. These patients can be successfully rehabilitated with cochlear implantation.

Distribution of Vesicular Glutamate Transporter 2 and Ionotropic Glutamate Receptors in the Auditory Ganglion and Cochlear Nuclei of Pigeons (Columba livia).

PubMed

Karim, M R; Atoji, Y

2016-02-01

Glutamate is a principal excitatory neurotransmitter in the auditory system. Our previous studies revealed localization of glutamate receptor mRNAs in the pigeon cochlear nuclei, suggesting the existence of glutamatergic input from the auditory nerve to the brainstem. This study demonstrated localization of mRNAs for vesicular glutamate transporter 2 (vGluT2) and ionotropic glutamate receptors (AMPA, kainate and NMDA) in the auditory ganglion (AG) and cochlear nuclei (magnocellular, angular and laminar nuclei). VGluT2 mRNA was intensely expressed in AG and intensely or moderately in the cochlear nuclei. The AG and cochlear nuclei showed intense-to-moderate mRNA signals for GluA2, GluA3, GluA4, GluK4 and GluN1. These results suggest that the pigeon AG neurons receives glutamatergic input from hair cells and in turn projects to the magnocellular and angular nuclei. Glutamate may play a pivotal role in the excitatory synapse transmission in the peripheral auditory pathway of birds. © 2015 Blackwell Verlag GmbH.

Challenges in Improving Cochlear Implant Performance and Accessibility.

PubMed

Zeng, Fan-Gang

2017-08-01

Here I identify two gaps in cochlear implants that have been limiting their performance and acceptance. First, cochlear implant performance has remained largely unchanged, despite the number of publications tripling per decade in the last 30 years. Little has been done so far to address a fundamental limitation in the electrode-to-neuron interface, with the electrode size being a thousand times larger than the neuron diameter while the number of electrodes being a thousand times less. Both the small number and the large size of electrodes produce broad spatial activation and poor frequency resolution that limit current cochlear implant performance. Second, a similarly rapid growth in cochlear implant volume has not produced an expected decrease in unit price in the same period. The high cost contributes to low market penetration rate, which is about 20% in developed countries and less than 1% in developing countries. I will discuss changes needed in both research strategy and business practice to close the gap between prosthetic and normal hearing as well as that between haves and have-nots.

Resistance of Gerbil Auditory Function to Reversible Decrease in Cochlear Blood Flow.

PubMed

El Afia, Fahd; Giraudet, Fabrice; Gilain, Laurent; Mom, Thierry; Avan, Paul

2017-01-01

The objective was to design in gerbils a model of reversible decrease in cochlear blood flow (CBF) and analyze its influence on cochlear function. In Mongolian gerbils injected with ferromagnetic microbeads, a magnet placed near the porus acusticus allowed CBF to be manipulated. The cochlear microphonic potential (CM) from the basal cochlea was monitored by a round-window electrode. In 13 of the 20 successfully injected gerbils, stable CBF reduction was obtained for 11.5 min on average. The CM was affected only when CBF fell to less than 60% of its baseline, yet remained >40% of its initial level in about 2/3 of such cases. After CBF restoration, CM recovery was fast and usually complete. Reduced CM came with a 35- to 45-dB threshold elevation of neural responses determined by compound action potentials. This method allowing reversible changes of CBF confirms the robustness of cochlear function to decreased CBF. It can be used to study whether a hypovascularized cochlea is abnormally sensitive to stress. © 2017 S. Karger AG, Basel.

Blood flow to the promontory in cochlear otosclerosis.

PubMed

Nakashima, T; Sone, M; Fujii, H; Teranishi, M; Yamamoto, H; Otake, H; Sugiura, M; Naganawa, S

2006-04-01

To investigate Schwartze sign with measurements of blood flow to the promontory in patients with cochlear otosclerosis. Prospective clinical study. Tertiary referral centre. Five patients with cochlear otosclerosis and five control subjects. Significant decalcification around the cochlea was observed by computed tomography (CT) in patients with cochlear otosclerosis. However, no recognizable lesion was observed at the oval window in two patients. One patient had mixed hearing loss and four patients had sensorineural hearing loss without an air-bone gap. The relationship between CT findings and the presence or absence of Schwartze sign was investigated. Blood flow to the promontory was measured through the tympanic membrane using laser speckle flowgraphy and laser Doppler flowmetry. The Schwartze sign correlated significantly with otosclerotic lesions invading the promontory. Patients with otosclerosis exhibited elevated and pulsating blood flow to the promontory with the Schwartze sign. Computed tomography demonstrated that cochlear otosclerosis can exist without the oval window lesion. Schwartze sign can be used as a sign of the otosclerotic invasion to the promontory. The reddening of the Schwartze sign is likely due to increased blood flow.

Microsurgical laser Doppler probe for simultaneous intraoperative monitoring of cochlear blood flow and electrocochleography from the round window

NASA Astrophysics Data System (ADS)

Abiy, Lidet; Telischi, Fred; Parel, Jean-Marie A.; Manns, Fabrice; Saettele, Ralph; Morawski, Krzysztof; Ozdamar, Ozcan; Borgos, John; Delgado, Rafael; Miskiel, Edward; Yavuz, Erdem

2003-06-01

The aim of this project is the development of a microsurgical laser Doppler (LD) probe that simultaneously monitors blood flow and Electrocochleography (ECochG) from the round window of the ear. The device will prevent neurosensory hearing loss during acoustic neuroma surgery by preventing damage to the internal auditory nerve and to the cochlear blood flow supply. A commercially available 0.5 mm diameter Laser-Doppler velocimetry probe (LaserFlo, Vasamedics) was modified to integrate an ECochG electrode. A tube for suction and irrigation was incorporated into a sheath of the probe shaft, to facilitate cleaning of the round window (RW) and allow drug delivery to the round window membrane. The prototype microprobe was calibrated on a single vessel model and tested in vivo in a rabbit model. Preliminary results indicate that the microprobe was able to measure changes in cochlear blood flow (CBF) and ECochG potentials from the round window of rabbits in vivo. The microprobe is suitable for monitoring cochlear blood flow and auditory cochlear potentials during human surgery.

Cochlear Modeling Using Time-Averaged Lagrangian" Method:. Comparison with VBM, PST, and ZC Measurements

NASA Astrophysics Data System (ADS)

Yoon, Y.; Kim, N.; Puria, S.; Steele, C. R.

2009-02-01

In this work, basilar membrane velocity (VBM), scala tympani intracochlear pressure (PST), and cochlear input impedances (Zc) for gerbil and chinchilla are implemented using a three-dimensional hydro-dynamic cochlear model using 1) time-averaged Lagrangian, 2) push-pull mechanism in active case, and 3) the complex anatomy of cochlear scalae by micro computed tomography (μCT) scanning and 3-D reconstructions of gerbil and chinchilla temporal bones. The objective of this work is to compare the calculations and the physiological measurements of gerbil and chinchilla cochlear such as VBM (Ren and Nuttall [1]), PST (Olson [2]), and ZC (Decraemer et al. [3], Songer and Rosowski [4], Ruggero et al. [5]) with present model. A WKB asymptotic method combined with Fourier series expansions is used to provide an efficient simulation. VBM and PST simulation results for the gerbil cochlea show good agreement both in the magnitude and the phase for the physiological measurements without larger phase excursion. ZC simulation from the gerbil and chinchilla model show reasonably good agreement with measurement.

Modeling and segmentation of intra-cochlear anatomy in conventional CT

NASA Astrophysics Data System (ADS)

Noble, Jack H.; Rutherford, Robert B.; Labadie, Robert F.; Majdani, Omid; Dawant, Benoit M.

2010-03-01

Cochlear implant surgery is a procedure performed to treat profound hearing loss. Since the cochlea is not visible in surgery, the physician uses anatomical landmarks to estimate the pose of the cochlea. Research has indicated that implanting the electrode in a particular cavity of the cochlea, the scala tympani, results in better hearing restoration. The success of the scala tympani implantation is largely dependent on the point of entry and angle of electrode insertion. Errors can occur due to the imprecise nature of landmark-based, manual navigation as well as inter-patient variations between scala tympani and the anatomical landmarks. In this work, we use point distribution models of the intra-cochlear anatomy to study the inter-patient variations between the cochlea and the typical anatomic landmarks, and we implement an active shape model technique to automatically localize intra-cochlear anatomy in conventional CT images, where intra-cochlear structures are not visible. This fully automatic segmentation could aid the surgeon to choose the point of entry and angle of approach to maximize the likelihood of scala tympani insertion, resulting in more substantial hearing restoration.

Minimally invasive surgical method to detect sound processing in the cochlear apex by optical coherence tomography

NASA Astrophysics Data System (ADS)

Ramamoorthy, Sripriya; Zhang, Yuan; Petrie, Tracy; Fridberger, Anders; Ren, Tianying; Wang, Ruikang; Jacques, Steven L.; Nuttall, Alfred L.

2016-02-01

Sound processing in the inner ear involves separation of the constituent frequencies along the length of the cochlea. Frequencies relevant to human speech (100 to 500 Hz) are processed in the apex region. Among mammals, the guinea pig cochlear apex processes similar frequencies and is thus relevant for the study of speech processing in the cochlea. However, the requirement for extensive surgery has challenged the optical accessibility of this area to investigate cochlear processing of signals without significant intrusion. A simple method is developed to provide optical access to the guinea pig cochlear apex in two directions with minimal surgery. Furthermore, all prior vibration measurements in the guinea pig apex involved opening an observation hole in the otic capsule, which has been questioned on the basis of the resulting changes to cochlear hydrodynamics. Here, this limitation is overcome by measuring the vibrations through the unopened otic capsule using phase-sensitive Fourier domain optical coherence tomography. The optically and surgically advanced method described here lays the foundation to perform minimally invasive investigation of speech-related signal processing in the cochlea.

Cochlear Implants

MedlinePlus

... newsroom@entnet.org . A cochlear implant is an electronic device that restores partial hearing to individuals with ... An internal component that consists of a small electronic device that is surgically implanted under the skin ...

Simultaneous bilateral cochlear implantation in a five-month-old child with Usher syndrome.

PubMed

Alsanosi, A A

2015-09-01

To report a rare case of simultaneous bilateral cochlear implantation in a five-month-old child with Usher syndrome. Case report. A five-month-old boy with Usher syndrome and congenital profound bilateral deafness underwent simultaneous bilateral cochlear implantation. The decision to perform implantation in such a young child was based on his having a supportive family and the desire to foster his audiological development before his vision deteriorated. The subject experienced easily resolvable intra- and post-operative adverse events, and was first fitted with an externally worn audio processor four weeks after implantation. At 14 months of age, his audiological development was age-appropriate. Simultaneous bilateral cochlear implantation is possible, and even advisable, in children as young as five months old when performed by an experienced implantation team.

Speech Perception for Adult Cochlear Implant Recipients in a Realistic Background Noise: Effectiveness of Preprocessing Strategies and External Options for Improving Speech Recognition in Noise

PubMed Central

Gifford, René H.; Revit, Lawrence J.

2014-01-01

Background Although cochlear implant patients are achieving increasingly higher levels of performance, speech perception in noise continues to be problematic. The newest generations of implant speech processors are equipped with preprocessing and/or external accessories that are purported to improve listening in noise. Most speech perception measures in the clinical setting, however, do not provide a close approximation to real-world listening environments. Purpose To assess speech perception for adult cochlear implant recipients in the presence of a realistic restaurant simulation generated by an eight-loudspeaker (R-SPACE™) array in order to determine whether commercially available preprocessing strategies and/or external accessories yield improved sentence recognition in noise. Research Design Single-subject, repeated-measures design with two groups of participants: Advanced Bionics and Cochlear Corporation recipients. Study Sample Thirty-four subjects, ranging in age from 18 to 90 yr (mean 54.5 yr), participated in this prospective study. Fourteen subjects were Advanced Bionics recipients, and 20 subjects were Cochlear Corporation recipients. Intervention Speech reception thresholds (SRTs) in semidiffuse restaurant noise originating from an eight-loudspeaker array were assessed with the subjects’ preferred listening programs as well as with the addition of either Beam™ preprocessing (Cochlear Corporation) or the T-Mic® accessory option (Advanced Bionics). Data Collection and Analysis In Experiment 1, adaptive SRTs with the Hearing in Noise Test sentences were obtained for all 34 subjects. For Cochlear Corporation recipients, SRTs were obtained with their preferred everyday listening program as well as with the addition of Focus preprocessing. For Advanced Bionics recipients, SRTs were obtained with the integrated behind-the-ear (BTE) mic as well as with the T-Mic. Statistical analysis using a repeated-measures analysis of variance (ANOVA) evaluated the effects of the preprocessing strategy or external accessory in reducing the SRT in noise. In addition, a standard t-test was run to evaluate effectiveness across manufacturer for improving the SRT in noise. In Experiment 2, 16 of the 20 Cochlear Corporation subjects were reassessed obtaining an SRT in noise using the manufacturer-suggested “Everyday,” “Noise,” and “Focus” preprocessing strategies. A repeated-measures ANOVA was employed to assess the effects of preprocessing. Results The primary findings were (i) both Noise and Focus preprocessing strategies (Cochlear Corporation) significantly improved the SRT in noise as compared to Everyday preprocessing, (ii) the T-Mic accessory option (Advanced Bionics) significantly improved the SRT as compared to the BTE mic, and (iii) Focus preprocessing and the T-Mic resulted in similar degrees of improvement that were not found to be significantly different from one another. Conclusion Options available in current cochlear implant sound processors are able to significantly improve speech understanding in a realistic, semidiffuse noise with both Cochlear Corporation and Advanced Bionics systems. For Cochlear Corporation recipients, Focus preprocessing yields the best speech-recognition performance in a complex listening environment; however, it is recommended that Noise preprocessing be used as the new default for everyday listening environments to avoid the need for switching programs throughout the day. For Advanced Bionics recipients, the T-Mic offers significantly improved performance in noise and is recommended for everyday use in all listening environments. PMID:20807480

A cochlear implant phantom for evaluating CT acquisition parameters

NASA Astrophysics Data System (ADS)

Chakravorti, Srijata; Bussey, Brian J.; Zhao, Yiyuan; Dawant, Benoit M.; Labadie, Robert F.; Noble, Jack H.

2017-03-01

Cochlear Implants (CIs) are surgically implantable neural prosthetic devices used to treat profound hearing loss. Recent literature indicates that there is a correlation between the positioning of the electrode array within the cochlea and the ultimate hearing outcome of the patient, indicating that further studies aimed at better understanding the relationship between electrode position and outcomes could have significant implications for future surgical techniques, array design, and processor programming methods. Post-implantation high resolution CT imaging is the best modality for localizing electrodes and provides the resolution necessary to visually identify electrode position, albeit with an unknown degree of accuracy depending on image acquisition parameters, like the HU range of reconstruction, radiation dose, and resolution of the image. In this paper, we report on the development of a phantom that will both permit studying which CT acquisition parameters are best for accurately identifying electrode position and serve as a ground truth for evaluating how different electrode localization methods perform when using different CT scanners and acquisition parameters. We conclude based on our tests that image resolution and HU range of reconstruction strongly affect how accurately the true position of the electrode array can be found by both experts and automatic analysis techniques. The results presented in this paper demonstrate that our phantom is a versatile tool for assessing how CT acquisition parameters affect the localization of CIs.

Parametric model of the scala tympani for haptic-rendered cochlear implantation.

PubMed

Todd, Catherine; Naghdy, Fazel

2005-01-01

A parametric model of the human scala tympani has been designed for use in a haptic-rendered computer simulation of cochlear implant surgery. It will be the first surgical simulator of this kind. A geometric model of the Scala Tympani has been derived from measured data for this purpose. The model is compared with two existing descriptions of the cochlear spiral. A first approximation of the basilar membrane is also produced. The structures are imported into a force-rendering software application for system development.

Music Therapy for Preschool Cochlear Implant Recipients

PubMed Central

Gfeller, Kate; Driscoll, Virginia; Kenworthy, Maura; Van Voorst, Tanya

2010-01-01

This paper provides research and clinical information relevant to music therapy for preschool children who use cochlear implants (CI). It consolidates information from various disciplinary sources regarding (a) cochlear implantation of young prelingually-deaf children (~age 2-5), (b) patterns of auditory and speech-language development, and (c) research regarding music perception of children with CIs. This information serves as a foundation for the final portion of the article, which describes typical music therapy goals and examples of interventions suitable for preschool children. PMID:23904691