One-tone suppression in the frog auditory nerve

DEFF Research Database (Denmark)

Christensen-Dalsgaard, J; Jørgensen, M B

1996-01-01

Sixty-seven fibers of a sample of 401 in the auditory nerve of grassfrogs (Rana temporaria) showed one-tone suppression, i.e., their spontaneous activity was suppressed by tones. All fibers were afferents from the amphibian papilla with best frequencies between 100 and 400 Hz. Best suppression...

Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

DEFF Research Database (Denmark)

Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

2017-01-01

In rodent models, acoustic exposure too modest to elevate hearing thresholds can nonetheless cause auditory nerve fiber deafferentation, interfering with the coding of supra-threshold sound. Low-spontaneous rate nerve fibers, important for encoding acoustic information at supra-threshold levels...... and in noise, are more susceptible to degeneration than high-spontaneous rate fibers. The change in auditory brainstem response (ABR) wave-V latency with noise level has been shown to be associated with auditory nerve deafferentation. Here, we measured ABR in a forward masking paradigm and evaluated wave......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

Auditory-nerve single-neuron thresholds to electrical stimulation from scala tympani electrodes.

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Parkins, C W; Colombo, J

1987-12-31

the involvement of higher level neurologic processes in the behavioral responses. These findings suggest that the basic principles of neural membrane function must be considered in developing or analyzing electrical stimulation strategies for cochlear prostheses if the appropriate stimulation of frequency specific populations of auditory-nerve neurons is the objective.

Presbycusis and auditory brainstem responses: a review

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Shilpa Khullar

2011-06-01

Full Text Available Age-related hearing loss or presbycusis is a complex phenomenon consisting of elevation of hearing levels as well as changes in the auditory processing. It is commonly classified into four categories depending on the cause. Auditory brainstem responses (ABRs are a type of early evoked potentials recorded within the first 10 ms of stimulation. They represent the synchronized activity of the auditory nerve and the brainstem. Some of the changes that occur in the aging auditory system may significantly influence the interpretation of the ABRs in comparison with the ABRs of the young adults. The waves of ABRs are described in terms of amplitude, latencies and interpeak latency of the different waves. There is a tendency of the amplitude to decrease and the absolute latencies to increase with advancing age but these trends are not always clear due to increase in threshold with advancing age that act a major confounding factor in the interpretation of ABRs.

A comparison of anesthetic agents and their effects on the response properties of the peripheral auditory system.

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Dodd, F; Capranica, R R

1992-10-01

Anesthetic agents were compared in order to identify the most appropriate agent for use during surgery and electrophysiological recordings in the auditory system of the tokay gecko (Gekko gecko). Each agent was first screened for anesthetic and analgesic properties and, if found satisfactory, it was subsequently tested in electrophysiological recordings in the auditory nerve. The following anesthetic agents fulfilled our criteria and were selected for further screening: sodium pentobarbital (60 mg/kg); sodium pentobarbital (30 mg/kg) and oxymorphone (1 mg/kg); 3.2% isoflurane; ketamine (440 mg/kg) and oxymorphone (1 mg/kg). These agents were subsequently compared on the basis of their effect on standard response properties of auditory nerve fibers. Our results verified that different anesthetic agents can have significant effects on most of the parameters commonly used in describing the basic response properties of the auditory system in vertebrates. We therefore conclude from this study that the selection of an appropriate experimental protocol is critical and must take into consideration the effects of anesthesia on auditory responsiveness. In the tokay gecko, we recommend 3.2% isoflurane for general surgical procedures; and for electrophysiological recordings in the eighth nerve we recommend barbiturate anesthesia of appropriate dosage in combination if possible with an opioid agent to provide additional analgesic action.

Analysis of electrically evoked compound action potential of the auditory nerve in children with bilateral cochlear implants.

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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.

The vestibulocochlear nerve (VIII).

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Benoudiba, F; Toulgoat, F; Sarrazin, J-L

2013-10-01

The vestibulocochlear nerve (8th cranial nerve) is a sensory nerve. It is made up of two nerves, the cochlear, which transmits sound and the vestibular which controls balance. It is an intracranial nerve which runs from the sensory receptors in the internal ear to the brain stem nuclei and finally to the auditory areas: the post-central gyrus and superior temporal auditory cortex. The most common lesions responsible for damage to VIII are vestibular Schwannomas. This report reviews the anatomy and various investigations of the nerve. Copyright © 2013. Published by Elsevier Masson SAS.

The human brain maintains contradictory and redundant auditory sensory predictions.

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Marika Pieszek

Full Text Available Computational and experimental research has revealed that auditory sensory predictions are derived from regularities of the current environment by using internal generative models. However, so far, what has not been addressed is how the auditory system handles situations giving rise to redundant or even contradictory predictions derived from different sources of information. To this end, we measured error signals in the event-related brain potentials (ERPs in response to violations of auditory predictions. Sounds could be predicted on the basis of overall probability, i.e., one sound was presented frequently and another sound rarely. Furthermore, each sound was predicted by an informative visual cue. Participants' task was to use the cue and to discriminate the two sounds as fast as possible. Violations of the probability based prediction (i.e., a rare sound as well as violations of the visual-auditory prediction (i.e., an incongruent sound elicited error signals in the ERPs (Mismatch Negativity [MMN] and Incongruency Response [IR]. Particular error signals were observed even in case the overall probability and the visual symbol predicted different sounds. That is, the auditory system concurrently maintains and tests contradictory predictions. Moreover, if the same sound was predicted, we observed an additive error signal (scalp potential and primary current density equaling the sum of the specific error signals. Thus, the auditory system maintains and tolerates functionally independently represented redundant and contradictory predictions. We argue that the auditory system exploits all currently active regularities in order to optimally prepare for future events.

Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei

DEFF Research Database (Denmark)

Tang, Y. Z.; Christensen-Dalsgaard, J.; Carr, C. E.

2012-01-01

We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of lo...... of auditory connections in lizards and archosaurs but also different processing of low- and high-frequency information in the brainstem. J. Comp. Neurol. 520:17841799, 2012. (C) 2011 Wiley Periodicals, Inc...

Neurophysiological assessment of auditory, peripheral nerve, somatosensory, and visual system function after developmental exposure to gasoline, E15, and E85 vapors.

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U.S. Environmental Protection Agency — Visual, auditory, somatosensory, and peripheral nerve evoked responses. This dataset is associated with the following publication: Herr , D., D. Freeborn , L. Degn ,...

Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

International Nuclear Information System (INIS)

Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul

2001-01-01

To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of

Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

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Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul [Sungkyunkwan Univ., School of Medicine, Seoul (Korea, Republic of)

2001-12-01

To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of

Effects of acoustic noise on the auditory nerve compound action potentials evoked by electric pulse trains.

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Nourski, Kirill V; Abbas, Paul J; Miller, Charles A; Robinson, Barbara K; Jeng, Fuh-Cherng

2005-04-01

This study investigated the effects of acoustic noise on the auditory nerve compound action potentials in response to electric pulse trains. Subjects were adult guinea pigs, implanted with a minimally invasive electrode to preserve acoustic sensitivity. Electrically evoked compound action potentials (ECAP) were recorded from the auditory nerve trunk in response to electric pulse trains both during and after the presentation of acoustic white noise. Simultaneously presented acoustic noise produced a decrease in ECAP amplitude. The effect of the acoustic masker on the electric probe was greatest at the onset of the acoustic stimulus and it was followed by a partial recovery of the ECAP amplitude. Following cessation of the acoustic noise, ECAP amplitude recovered over a period of approximately 100-200 ms. The effects of the acoustic noise were more prominent at lower electric pulse rates (interpulse intervals of 3 ms and higher). At higher pulse rates, the ECAP adaptation to the electric pulse train alone was larger and the acoustic noise, when presented, produced little additional effect. The observed effects of noise on ECAP were the greatest at high electric stimulus levels and, for a particular electric stimulus level, at high acoustic noise levels.

A Model of Electrically Stimulated Auditory Nerve Fiber Responses with Peripheral and Central Sites of Spike Generation

DEFF Research Database (Denmark)

Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

2017-01-01

. A single ANF is modeled as a network of two exponential integrateand-fire point-neuron models, referred to as peripheral and central axons of the ANF. The peripheral axon is excited by the cathodic charge, inhibited by the anodic charge, and exhibits longer spike latencies than the central axon......A computational model of cat auditory nerve fiber (ANF) responses to electrical stimulation is presented. The model assumes that (1) there exist at least two sites of spike generation along the ANF and (2) both an anodic (positive) and a cathodic (negative) charge in isolation can evoke a spike......; the central axon is excited by the anodic charge, inhibited by the cathodic charge, and exhibits shorter spike latencies than the peripheral axon. The model also includes subthreshold and suprathreshold adaptive feedback loops which continuously modify the membrane potential and can account for effects...

Cell-type specific short-term plasticity at auditory nerve synapses controls feed-forward inhibition in the dorsal cochlear nucleus

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Miloslav eSedlacek

2014-07-01

Full Text Available Feedforward inhibition represents a powerful mechanism by which control of the timing and fidelity of action potentials in local synaptic circuits of various brain regions is achieved. In the cochlear nucleus, the auditory nerve provides excitation to both principal neurons and inhibitory interneurons. Here, we investigated the synaptic circuit associated with fusiform cells (FCs, principal neurons of the dorsal cochlear nucleus (DCN that receive excitation from auditory nerve fibers and inhibition from tuberculoventral cells (TVCs on their basal dendrites in the deep layer of DCN. Despite the importance of these inputs in regulating fusiform cell firing behavior, the mechanisms determining the balance of excitation and feed-forward inhibition in this circuit are not well understood. Therefore, we examined the timing and plasticity of auditory nerve driven feed-forward inhibition (FFI onto FCs. We find that in some FCs, excitatory and inhibitory components of feed-forward inhibition had the same stimulation thresholds indicating they could be triggered by activation of the same fibers. In other FCs, excitation and inhibition exhibit different stimulus thresholds, suggesting FCs and TVCs might be activated by different sets of fibers. In addition we find that during repetitive activation, synapses formed by the auditory nerve onto TVCs and FCs exhibit distinct modes of short-term plasticity. Feed-forward inhibitory post-synaptic currents (IPSCs in FCs exhibit short-term depression because of prominent synaptic depression at the auditory nerve-TVC synapse. Depression of this feedforward inhibitory input causes a shift in the balance of fusiform cell synaptic input towards greater excitation and suggests that fusiform cell spike output will be enhanced by physiological patterns of auditory nerve activity.

Cell-type specific short-term plasticity at auditory nerve synapses controls feed-forward inhibition in the dorsal cochlear nucleus.

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Sedlacek, Miloslav; Brenowitz, Stephan D

2014-01-01

Feed-forward inhibition (FFI) represents a powerful mechanism by which control of the timing and fidelity of action potentials in local synaptic circuits of various brain regions is achieved. In the cochlear nucleus, the auditory nerve provides excitation to both principal neurons and inhibitory interneurons. Here, we investigated the synaptic circuit associated with fusiform cells (FCs), principal neurons of the dorsal cochlear nucleus (DCN) that receive excitation from auditory nerve fibers and inhibition from tuberculoventral cells (TVCs) on their basal dendrites in the deep layer of DCN. Despite the importance of these inputs in regulating fusiform cell firing behavior, the mechanisms determining the balance of excitation and FFI in this circuit are not well understood. Therefore, we examined the timing and plasticity of auditory nerve driven FFI onto FCs. We find that in some FCs, excitatory and inhibitory components of FFI had the same stimulation thresholds indicating they could be triggered by activation of the same fibers. In other FCs, excitation and inhibition exhibit different stimulus thresholds, suggesting FCs and TVCs might be activated by different sets of fibers. In addition, we find that during repetitive activation, synapses formed by the auditory nerve onto TVCs and FCs exhibit distinct modes of short-term plasticity. Feed-forward inhibitory post-synaptic currents (IPSCs) in FCs exhibit short-term depression because of prominent synaptic depression at the auditory nerve-TVC synapse. Depression of this feedforward inhibitory input causes a shift in the balance of fusiform cell synaptic input towards greater excitation and suggests that fusiform cell spike output will be enhanced by physiological patterns of auditory nerve activity.

Predictive coding of visual-auditory and motor-auditory events: An electrophysiological study.

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Stekelenburg, Jeroen J; Vroomen, Jean

2015-11-11

The amplitude of auditory components of the event-related potential (ERP) is attenuated when sounds are self-generated compared to externally generated sounds. This effect has been ascribed to internal forward modals predicting the sensory consequences of one's own motor actions. Auditory potentials are also attenuated when a sound is accompanied by a video of anticipatory visual motion that reliably predicts the sound. Here, we investigated whether the neural underpinnings of prediction of upcoming auditory stimuli are similar for motor-auditory (MA) and visual-auditory (VA) events using a stimulus omission paradigm. In the MA condition, a finger tap triggered the sound of a handclap whereas in the VA condition the same sound was accompanied by a video showing the handclap. In both conditions, the auditory stimulus was omitted in either 50% or 12% of the trials. These auditory omissions induced early and mid-latency ERP components (oN1 and oN2, presumably reflecting prediction and prediction error), and subsequent higher-order error evaluation processes. The oN1 and oN2 of MA and VA were alike in amplitude, topography, and neural sources despite that the origin of the prediction stems from different brain areas (motor versus visual cortex). This suggests that MA and VA predictions activate a sensory template of the sound in auditory cortex. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2015 Elsevier B.V. All rights reserved.

Nerve Ultrasound Predicts Treatment Response in Chronic Inflammatory Demyelinating Polyradiculoneuropathy-a Prospective Follow-Up.

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Härtig, Florian; Ross, Marlene; Dammeier, Nele Maria; Fedtke, Nadin; Heiling, Bianka; Axer, Hubertus; Décard, Bernhard F; Auffenberg, Eva; Koch, Marilin; Rattay, Tim W; Krumbholz, Markus; Bornemann, Antje; Lerche, Holger; Winter, Natalie; Grimm, Alexander

2018-04-01

As reliable biomarkers of disease activity are lacking, monitoring of therapeutic response in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) remains a challenge. We sought to determine whether nerve ultrasound and electrophysiology scoring could close this gap. In CIDP patients (fulfilling EFNS/PNS criteria), we performed high-resolution nerve ultrasound to determine ultrasound pattern sum scores (UPSS) and predominant echotexture nerve conduction study scores (NCSS) as well as Medical Research Council sum scores (MRCSS) and inflammatory neuropathy cause and treatment disability scores (INCAT) at baseline and after 12 months of standard treatment. We retrospectively correlated ultrasound morphology with nerve histology when available. 72/80 CIDP patients featured multifocal nerve enlargement, and 35/80 were therapy-naïve. At baseline, clinical scores correlated with NCSS (r 2  = 0.397 and r 2  = 0.443, p  50% of measured segments, possibly reflecting axonal degeneration; and 3) almost no enlargement, reflecting "burned-out" or "cured" disease without active inflammation. Clinical improvement after 12 months was best in patients with pattern 1 (up to 75% vs up to 43% in pattern 2/3, Fisher's exact test p < 0.05). Nerve ultrasound has additional value not only for diagnosis, but also for classification of disease state and may predict treatment response.

Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

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Françoise eLecaignard

2015-09-01

Full Text Available Deviant stimuli, violating regularities in a sensory environment, elicit the Mismatch Negativity (MMN, largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities.

Improved Transient Response Estimations in Predicting 40 Hz Auditory Steady-State Response Using Deconvolution Methods

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Xiaodan Tan

2017-12-01

Full Text Available The auditory steady-state response (ASSR is one of the main approaches in clinic for health screening and frequency-specific hearing assessment. However, its generation mechanism is still of much controversy. In the present study, the linear superposition hypothesis for the generation of ASSRs was investigated by comparing the relationships between the classical 40 Hz ASSR and three synthetic ASSRs obtained from three different templates for transient auditory evoked potential (AEP. These three AEPs are the traditional AEP at 5 Hz and two 40 Hz AEPs derived from two deconvolution algorithms using stimulus sequences, i.e., continuous loop averaging deconvolution (CLAD and multi-rate steady-state average deconvolution (MSAD. CLAD requires irregular inter-stimulus intervals (ISIs in the sequence while MSAD uses the same ISIs but evenly-spaced stimulus sequences which mimics the classical 40 Hz ASSR. It has been reported that these reconstructed templates show similar patterns but significant difference in morphology and distinct frequency characteristics in synthetic ASSRs. The prediction accuracies of ASSR using these templates show significant differences (p < 0.05 in 45.95, 36.28, and 10.84% of total time points within four cycles of ASSR for the traditional, CLAD, and MSAD templates, respectively, as compared with the classical 40 Hz ASSR, and the ASSR synthesized from the MSAD transient AEP suggests the best similarity. And such a similarity is also demonstrated at individuals only in MSAD showing no statistically significant difference (Hotelling's T2 test, T2 = 6.96, F = 0.80, p = 0.592 as compared with the classical 40 Hz ASSR. The present results indicate that both stimulation rate and sequencing factor (ISI variation affect transient AEP reconstructions from steady-state stimulation protocols. Furthermore, both auditory brainstem response (ABR and middle latency response (MLR are observed in contributing to the composition of ASSR but

Predicting hearing thresholds and occupational hearing loss with multiple-frequency auditory steady-state responses.

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Hsu, Ruey-Fen; Ho, Chi-Kung; Lu, Sheng-Nan; Chen, Shun-Sheng

2010-10-01

An objective investigation is needed to verify the existence and severity of hearing impairments resulting from work-related, noise-induced hearing loss in arbitration of medicolegal aspects. We investigated the accuracy of multiple-frequency auditory steady-state responses (Mf-ASSRs) between subjects with sensorineural hearing loss (SNHL) with and without occupational noise exposure. Cross-sectional study. Tertiary referral medical centre. Pure-tone audiometry and Mf-ASSRs were recorded in 88 subjects (34 patients had occupational noise-induced hearing loss [NIHL], 36 patients had SNHL without noise exposure, and 18 volunteers were normal controls). Inter- and intragroup comparisons were made. A predicting equation was derived using multiple linear regression analysis. ASSRs and pure-tone thresholds (PTTs) showed a strong correlation for all subjects (r = .77 ≈ .94). The relationship is demonstrated by the equationThe differences between the ASSR and PTT were significantly higher for the NIHL group than for the subjects with non-noise-induced SNHL (p tool for objectively evaluating hearing thresholds. Predictive value may be lower in subjects with occupational hearing loss. Regardless of carrier frequencies, the severity of hearing loss affects the steady-state response. Moreover, the ASSR may assist in detecting noise-induced injury of the auditory pathway. A multiple linear regression equation to accurately predict thresholds was shown that takes into consideration all effect factors.

Significance of bone changes at the meatus acusticus internus in tumours of the auditory nerve and in the 'empty' extended internal auditory meatus

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Grehn, S.

1988-06-01

The unilateral extension of shortening of the internal auditory meatus is a very safe bony sign of the presence of a neurinoma of the auditory nerve. Differential diagnosis is necessary to exclude an 'empty' extended internal auditory meatus. On the other hand, 31% of the definitely established neurinomas do not show up in the plain tomogram. These facts prove that despite the presence or absence of allegedly definite bony changes at the internal auditory meatus further diagnostic measures are imperative, especially an air meatography in conjunction with high resolution computed tomography.

Binaural processing by the gecko auditory periphery.

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Christensen-Dalsgaard, Jakob; Tang, Yezhong; Carr, Catherine E

2011-05-01

Lizards have highly directional ears, owing to strong acoustical coupling of the eardrums and almost perfect sound transmission from the contralateral ear. To investigate the neural processing of this remarkable tympanic directionality, we combined biophysical measurements of eardrum motion in the Tokay gecko with neurophysiological recordings from the auditory nerve. Laser vibrometry shows that their ear is a two-input system with approximately unity interaural transmission gain at the peak frequency (∼ 1.6 kHz). Median interaural delays are 260 μs, almost three times larger than predicted from gecko head size, suggesting interaural transmission may be boosted by resonances in the large, open mouth cavity (Vossen et al. 2010). Auditory nerve recordings are sensitive to both interaural time differences (ITD) and interaural level differences (ILD), reflecting the acoustical interactions of direct and indirect sound components at the eardrum. Best ITD and click delays match interaural transmission delays, with a range of 200-500 μs. Inserting a mold in the mouth cavity blocks ITD and ILD sensitivity. Thus the neural response accurately reflects tympanic directionality, and most neurons in the auditory pathway should be directional.

A Review of Auditory Prediction and Its Potential Role in Tinnitus Perception.

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Durai, Mithila; O'Keeffe, Mary G; Searchfield, Grant D

2018-06-01

The precise mechanisms underlying tinnitus perception and distress are still not fully understood. A recent proposition is that auditory prediction errors and related memory representations may play a role in driving tinnitus perception. It is of interest to further explore this. To obtain a comprehensive narrative synthesis of current research in relation to auditory prediction and its potential role in tinnitus perception and severity. A narrative review methodological framework was followed. The key words Prediction Auditory, Memory Prediction Auditory, Tinnitus AND Memory, Tinnitus AND Prediction in Article Title, Abstract, and Keywords were extensively searched on four databases: PubMed, Scopus, SpringerLink, and PsychINFO. All study types were selected from 2000-2016 (end of 2016) and had the following exclusion criteria applied: minimum age of participants article not available in English. Reference lists of articles were reviewed to identify any further relevant studies. Articles were short listed based on title relevance. After reading the abstracts and with consensus made between coauthors, a total of 114 studies were selected for charting data. The hierarchical predictive coding model based on the Bayesian brain hypothesis, attentional modulation and top-down feedback serves as the fundamental framework in current literature for how auditory prediction may occur. Predictions are integral to speech and music processing, as well as in sequential processing and identification of auditory objects during auditory streaming. Although deviant responses are observable from middle latency time ranges, the mismatch negativity (MMN) waveform is the most commonly studied electrophysiological index of auditory irregularity detection. However, limitations may apply when interpreting findings because of the debatable origin of the MMN and its restricted ability to model real-life, more complex auditory phenomenon. Cortical oscillatory band activity may act as

Towards Clinical Application of Neurotrophic Factors to the Auditory Nerve; Assessment of Safety and Efficacy by a Systematic Review of Neurotrophic Treatments in Humans

NARCIS (Netherlands)

Bezdjian, Aren; Kraaijenga, Véronique J C; Ramekers, Dyan; Versnel, Huib; Thomeer, Hans G X M; Klis, Sjaak F L; Grolman, Wilko

2016-01-01

Animal studies have evidenced protection of the auditory nerve by exogenous neurotrophic factors. In order to assess clinical applicability of neurotrophic treatment of the auditory nerve, the safety and efficacy of neurotrophic therapies in various human disorders were systematically reviewed.

A phenomenological model of the electrically stimulated auditory nerve fiber: temporal and biphasic response properties

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Colin eHorne

2016-02-01

Full Text Available We present a phenomenological model of electrically stimulated auditory nerve fibers (ANFs. The model reproduces the probabilistic and temporal properties of the ANF response to both monophasic and biphasic stimuli, in isolation. The main contribution of the model lies in its ability to reproduce statistics of the ANF response (mean latency, jitter, and firing probability under both monophasic and cathodic-anodic biphasic stimulation, without changing the model’s parameters. The response statistics of the model depend on stimulus level and duration of the stimulating pulse, reproducing trends observed in the ANF. In the case of biphasic stimulation, the model reproduces the effects of pseudomonophasic pulse shapes and also the dependence on the interphase gap (IPG of the stimulus pulse, an effect that is quantitatively reproduced. The model is fitted to ANF data using a procedure that uniquely determines each model parameter. It is thus possible to rapidly parameterize a large population of neurons to reproduce a given set of response statistic distributions.Our work extends the stochastic leaky integrate and fire (SLIF neuron, a well-studied phenomenological model of the electrically stimulated neuron. We extend the SLIF neuron so as to produce a realistic latency distribution by delaying the moment of spiking. During this delay, spiking may be abolished by anodic current. By this means, the probability of the model neuron responding to a stimulus is reduced when a trailing phase of opposite polarity is introduced. By introducing a minimum wait period that must elapse before a spike may be emitted, the model is able to reproduce the differences in the threshold level observed in the ANF for monophasic and biphasic stimuli. Thus, the ANF response to a large variety of pulse shapes are reproduced correctly by this model.

Visual form predictions facilitate auditory processing at the N1.

Science.gov (United States)

Paris, Tim; Kim, Jeesun; Davis, Chris

2017-02-20

Auditory-visual (AV) events often involve a leading visual cue (e.g. auditory-visual speech) that allows the perceiver to generate predictions about the upcoming auditory event. Electrophysiological evidence suggests that when an auditory event is predicted, processing is sped up, i.e., the N1 component of the ERP occurs earlier (N1 facilitation). However, it is not clear (1) whether N1 facilitation is based specifically on predictive rather than multisensory integration and (2) which particular properties of the visual cue it is based on. The current experiment used artificial AV stimuli in which visual cues predicted but did not co-occur with auditory cues. Visual form cues (high and low salience) and the auditory-visual pairing were manipulated so that auditory predictions could be based on form and timing or on timing only. The results showed that N1 facilitation occurred only for combined form and temporal predictions. These results suggest that faster auditory processing (as indicated by N1 facilitation) is based on predictive processing generated by a visual cue that clearly predicts both what and when the auditory stimulus will occur. Copyright © 2016. Published by Elsevier Ltd.

The cochlear nerve canal and internal auditory canal in children with normal cochlea but cochlear nerve deficiency

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Yan, Fei; Li, Jianhong; Xian, Junfang; Wang, Zhenchang; Mo, Lingyan

2013-01-01

Background: There is an increasing frequency of requests for cochlear implantation (CI) in deaf children and more detailed image information is necessary for selecting appropriate candidates. Cochlear nerve deficiency (CND) is a contraindication to CI. Magnetic resonance imaging (MRI) has been used to evaluate the integrity of the cochlear nerve. The abnormalities of the cochlear nerve canal (CNC) and internal auditory canal (IAC) have been reported to be associated with CND. Purpose: To correlate CNC manifestation, size, and IAC diameter on high-resolution CT (HRCT) with CND diagnosed by MRI in children. Material and Methods: HRCT images from 35 sensorineurally deaf children who had normal cochlea but bilateral or unilateral CND diagnosed by MRI were studied retrospectively. The CNC and IAC manifestation and size were assessed and correlated with CND. Results: CND was diagnosed by MRI in 54/70 ears (77.1%). Thirty-two ears had an absent cochlear nerve (59.3%), while 22 ears had a small cochlear nerve (40.7%). The CNC diameter was 2.0 mm in 11 ears (20.4%). The IAC diameter was 3.0 mm in 29 ears (53.7%). Conclusion: The hypoplastic CNC might be more highly indicative of CND than that of a narrow IAC

Neural correlates of auditory temporal predictions during sensorimotor synchronization

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Nadine ePecenka

2013-08-01

Full Text Available Musical ensemble performance requires temporally precise interpersonal action coordination. To play in synchrony, ensemble musicians presumably rely on anticipatory mechanisms that enable them to predict the timing of sounds produced by co-performers. Previous studies have shown that individuals differ in their ability to predict upcoming tempo changes in paced finger-tapping tasks (indexed by cross-correlations between tap timing and pacing events and that the degree of such prediction influences the accuracy of sensorimotor synchronization (SMS and interpersonal coordination in dyadic tapping tasks. The current functional magnetic resonance imaging study investigated the neural correlates of auditory temporal predictions during SMS in a within-subject design. Hemodynamic responses were recorded from 18 musicians while they tapped in synchrony with auditory sequences containing gradual tempo changes under conditions of varying cognitive load (achieved by a simultaneous visual n-back working-memory task comprising three levels of difficulty: observation only, 1-back, and 2-back object comparisons. Prediction ability during SMS decreased with increasing cognitive load. Results of a parametric analysis revealed that the generation of auditory temporal predictions during SMS recruits (1 a distributed network in cortico-cerebellar motor-related brain areas (left dorsal premotor and motor cortex, right lateral cerebellum, SMA proper and bilateral inferior parietal cortex and (2 medial cortical areas (medial prefrontal cortex, posterior cingulate cortex. While the first network is presumably involved in basic sensory prediction, sensorimotor integration, motor timing, and temporal adaptation, activation in the second set of areas may be related to higher-level social-cognitive processes elicited during action coordination with auditory signals that resemble music performed by human agents.

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

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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

Modeling the time-varying and level-dependent effects of the medial olivocochlear reflex in auditory nerve responses.

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Smalt, Christopher J; Heinz, Michael G; Strickland, Elizabeth A

2014-04-01

The medial olivocochlear reflex (MOCR) has been hypothesized to provide benefit for listening in noisy environments. This advantage can be attributed to a feedback mechanism that suppresses auditory nerve (AN) firing in continuous background noise, resulting in increased sensitivity to a tone or speech. MOC neurons synapse on outer hair cells (OHCs), and their activity effectively reduces cochlear gain. The computational model developed in this study implements the time-varying, characteristic frequency (CF) and level-dependent effects of the MOCR within the framework of a well-established model for normal and hearing-impaired AN responses. A second-order linear system was used to model the time-course of the MOCR using physiological data in humans. The stimulus-level-dependent parameters of the efferent pathway were estimated by fitting AN sensitivity derived from responses in decerebrate cats using a tone-in-noise paradigm. The resulting model uses a binaural, time-varying, CF-dependent, level-dependent OHC gain reduction for both ipsilateral and contralateral stimuli that improves detection of a tone in noise, similarly to recorded AN responses. The MOCR may be important for speech recognition in continuous background noise as well as for protection from acoustic trauma. Further study of this model and its efferent feedback loop may improve our understanding of the effects of sensorineural hearing loss in noisy situations, a condition in which hearing aids currently struggle to restore normal speech perception.

The cochlear nerve canal and internal auditory canal in children with normal cochlea but cochlear nerve deficiency

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Yan, Fei; Li, Jianhong; Xian, Junfang; Wang, Zhenchang [Dept. of Radiology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)], e-mail: cjr.wzhch@vip.163.com; Mo, Lingyan [Dept. of Otorhinolaryngology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)

2013-04-15

Background: There is an increasing frequency of requests for cochlear implantation (CI) in deaf children and more detailed image information is necessary for selecting appropriate candidates. Cochlear nerve deficiency (CND) is a contraindication to CI. Magnetic resonance imaging (MRI) has been used to evaluate the integrity of the cochlear nerve. The abnormalities of the cochlear nerve canal (CNC) and internal auditory canal (IAC) have been reported to be associated with CND. Purpose: To correlate CNC manifestation, size, and IAC diameter on high-resolution CT (HRCT) with CND diagnosed by MRI in children. Material and Methods: HRCT images from 35 sensorineurally deaf children who had normal cochlea but bilateral or unilateral CND diagnosed by MRI were studied retrospectively. The CNC and IAC manifestation and size were assessed and correlated with CND. Results: CND was diagnosed by MRI in 54/70 ears (77.1%). Thirty-two ears had an absent cochlear nerve (59.3%), while 22 ears had a small cochlear nerve (40.7%). The CNC diameter was <1.5 mm in 36 ears (66.7%). The CNC diameter ranged between 1.5 and 2.0 mm in seven ears (13.0%) and was >2.0 mm in 11 ears (20.4%). The IAC diameter was <3.0 mm in 25 ears (46.3%) and >3.0 mm in 29 ears (53.7%). Conclusion: The hypoplastic CNC might be more highly indicative of CND than that of a narrow IAC.

Needle in the external auditory canal: an unusual complication of inferior alveolar nerve block.

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Ribeiro, Leandro; Ramalho, Sara; Gerós, Sandra; Ferreira, Edite Coimbra; Faria e Almeida, António; Condé, Artur

2014-06-01

Inferior alveolar nerve block is used to anesthetize the ipsilateral mandible. The most commonly used technique is one in which the anesthetic is injected directly into the pterygomandibular space, by an intraoral approach. The fracture of the needle, although uncommon, can lead to potentially serious complications. The needle is usually found in the pterygomandibular space, although it can migrate and damage adjacent structures, with variable consequences. The authors report an unusual case of a fractured needle, migrating to the external auditory canal, as a result of an inferior alveolar nerve block. Copyright © 2014 Elsevier Inc. All rights reserved.

Prediction of cognitive outcome based on the progression of auditory discrimination during coma.

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Juan, Elsa; De Lucia, Marzia; Tzovara, Athina; Beaud, Valérie; Oddo, Mauro; Clarke, Stephanie; Rossetti, Andrea O

2016-09-01

To date, no clinical test is able to predict cognitive and functional outcome of cardiac arrest survivors. Improvement of auditory discrimination in acute coma indicates survival with high specificity. Whether the degree of this improvement is indicative of recovery remains unknown. Here we investigated if progression of auditory discrimination can predict cognitive and functional outcome. We prospectively recorded electroencephalography responses to auditory stimuli of post-anoxic comatose patients on the first and second day after admission. For each recording, auditory discrimination was quantified and its evolution over the two recordings was used to classify survivors as "predicted" when it increased vs. "other" if not. Cognitive functions were tested on awakening and functional outcome was assessed at 3 months using the Cerebral Performance Categories (CPC) scale. Thirty-two patients were included, 14 "predicted survivors" and 18 "other survivors". "Predicted survivors" were more likely to recover basic cognitive functions shortly after awakening (ability to follow a standardized neuropsychological battery: 86% vs. 44%; p=0.03 (Fisher)) and to show a very good functional outcome at 3 months (CPC 1: 86% vs. 33%; p=0.004 (Fisher)). Moreover, progression of auditory discrimination during coma was strongly correlated with cognitive performance on awakening (phonemic verbal fluency: rs=0.48; p=0.009 (Spearman)). Progression of auditory discrimination during coma provides early indication of future recovery of cognitive functions. The degree of improvement is informative of the degree of functional impairment. If confirmed in a larger cohort, this test would be the first to predict detailed outcome at the single-patient level. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A Model-Based Approach for Separating the Cochlear Microphonic from the Auditory Nerve Neurophonic in the Ongoing Response Using Electrocochleography

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Tatyana E. Fontenot

2017-10-01

Full Text Available Electrocochleography (ECochG is a potential clinically valuable technique for predicting speech perception outcomes in cochlear implant (CI recipients, among other uses. Current analysis is limited by an inability to quantify hair cell and neural contributions which are mixed in the ongoing part of the response to low frequency tones. Here, we used a model based on source properties to account for recorded waveform shapes and to separate the combined signal into its components. The model for the cochlear microphonic (CM was a sinusoid with parameters for independent saturation of the peaks and the troughs of the responses. The model for the auditory nerve neurophonic (ANN was the convolution of a unit potential and population cycle histogram with a parameter for spread of excitation. Phases of the ANN and CM were additional parameters. The average cycle from the ongoing response was the input, and adaptive fitting identified CM and ANN parameters that best reproduced the waveform shape. Test datasets were responses recorded from the round windows of CI recipients, from the round window of gerbils before and after application of neurotoxins, and with simulated signals where each parameter could be manipulated in isolation. Waveforms recorded from 284 CI recipients had a variety of morphologies that the model fit with an average r2 of 0.97 ± 0.058 (standard deviation. With simulated signals, small systematic differences between outputs and inputs were seen with some variable combinations, but in general there were limited interactions among the parameters. In gerbils, the CM reported was relatively unaffected by the neurotoxins. In contrast, the ANN was strongly reduced and the reduction was limited to frequencies of 1,000 Hz and lower, consistent with the range of strong neural phase-locking. Across human CI subjects, the ANN contribution was variable, ranging from nearly none to larger than the CM. Development of this model could provide a

Effect of Bluetooth headset and mobile phone electromagnetic fields on the human auditory nerve.

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Mandalà, Marco; Colletti, Vittorio; Sacchetto, Luca; Manganotti, Paolo; Ramat, Stefano; Marcocci, Alessandro; Colletti, Liliana

2014-01-01

The possibility that long-term mobile phone use increases the incidence of astrocytoma, glioma and acoustic neuroma has been investigated in several studies. Recently, our group showed that direct exposure (in a surgical setting) to cell phone electromagnetic fields (EMFs) induces deterioration of auditory evoked cochlear nerve compound action potential (CNAP) in humans. To verify whether the use of Bluetooth devices reduces these effects, we conducted the present study with the same experimental protocol. Randomized trial. Twelve patients underwent retrosigmoid vestibular neurectomy to treat definite unilateral Ménière's disease while being monitored with acoustically evoked CNAPs to assess direct mobile phone exposure or alternatively the EMF effects of Bluetooth headsets. We found no short-term effects of Bluetooth EMFs on the auditory nervous structures, whereas direct mobile phone EMF exposure confirmed a significant decrease in CNAPs amplitude and an increase in latency in all subjects. The outcomes of the present study show that, contrary to the finding that the latency and amplitude of CNAPs are very sensitive to EMFs produced by the tested mobile phone, the EMFs produced by a common Bluetooth device do not induce any significant change in cochlear nerve activity. The conditions of exposure, therefore, differ from those of everyday life, in which various biological tissues may reduce the EMF affecting the cochlear nerve. Nevertheless, these novel findings may have important safety implications. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Adaptation in the auditory system: an overview

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David ePérez-González

2014-02-01

Full Text Available The early stages of the auditory system need to preserve the timing information of sounds in order to extract the basic features of acoustic stimuli. At the same time, different processes of neuronal adaptation occur at several levels to further process the auditory information. For instance, auditory nerve fiber responses already experience adaptation of their firing rates, a type of response that can be found in many other auditory nuclei and may be useful for emphasizing the onset of the stimuli. However, it is at higher levels in the auditory hierarchy where more sophisticated types of neuronal processing take place. For example, stimulus-specific adaptation, where neurons show adaptation to frequent, repetitive stimuli, but maintain their responsiveness to stimuli with different physical characteristics, thus representing a distinct kind of processing that may play a role in change and deviance detection. In the auditory cortex, adaptation takes more elaborate forms, and contributes to the processing of complex sequences, auditory scene analysis and attention. Here we review the multiple types of adaptation that occur in the auditory system, which are part of the pool of resources that the neurons employ to process the auditory scene, and are critical to a proper understanding of the neuronal mechanisms that govern auditory perception.

Towards Clinical Application of Neurotrophic Factors to the Auditory Nerve; Assessment of Safety and Efficacy by a Systematic Review of Neurotrophic Treatments in Humans

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Aren Bezdjian

2016-11-01

Full Text Available Animal studies have evidenced protection of the auditory nerve by exogenous neurotrophic factors. In order to assess clinical applicability of neurotrophic treatment of the auditory nerve, the safety and efficacy of neurotrophic therapies in various human disorders were systematically reviewed. Outcomes of our literature search included disorder, neurotrophic factor, administration route, therapeutic outcome, and adverse event. From 2103 articles retrieved, 20 randomized controlled trials including 3974 patients were selected. Amyotrophic lateral sclerosis (53% was the most frequently reported indication for neurotrophic therapy followed by diabetic polyneuropathy (28%. Ciliary neurotrophic factor (50%, nerve growth factor (24% and insulin-like growth factor (21% were most often used. Injection site reaction was a frequently occurring adverse event (61% followed by asthenia (24% and gastrointestinal disturbances (20%. Eighteen out of 20 trials deemed neurotrophic therapy to be safe, and six out of 17 studies concluded the neurotrophic therapy to be effective. Positive outcomes were generally small or contradicted by other studies. Most non-neurodegenerative diseases treated by targeted deliveries of neurotrophic factors were considered safe and effective. Hence, since local delivery to the cochlea is feasible, translation from animal studies to human trials in treating auditory nerve degeneration seems promising.

A hardware model of the auditory periphery to transduce acoustic signals into neural activity

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Takashi eTateno

2013-11-01

Full Text Available To improve the performance of cochlear implants, we have integrated a microdevice into a model of the auditory periphery with the goal of creating a microprocessor. We constructed an artificial peripheral auditory system using a hybrid model in which polyvinylidene difluoride was used as a piezoelectric sensor to convert mechanical stimuli into electric signals. To produce frequency selectivity, the slit on a stainless steel base plate was designed such that the local resonance frequency of the membrane over the slit reflected the transfer function. In the acoustic sensor, electric signals were generated based on the piezoelectric effect from local stress in the membrane. The electrodes on the resonating plate produced relatively large electric output signals. The signals were fed into a computer model that mimicked some functions of inner hair cells, inner hair cell–auditory nerve synapses, and auditory nerve fibers. In general, the responses of the model to pure-tone burst and complex stimuli accurately represented the discharge rates of high-spontaneous-rate auditory nerve fibers across a range of frequencies greater than 1 kHz and middle to high sound pressure levels. Thus, the model provides a tool to understand information processing in the peripheral auditory system and a basic design for connecting artificial acoustic sensors to the peripheral auditory nervous system. Finally, we discuss the need for stimulus control with an appropriate model of the auditory periphery based on auditory brainstem responses that were electrically evoked by different temporal pulse patterns with the same pulse number.

Differential contribution of visual and auditory information to accurately predict the direction and rotational motion of a visual stimulus.

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Park, Seoung Hoon; Kim, Seonjin; Kwon, MinHyuk; Christou, Evangelos A

2016-03-01

Vision and auditory information are critical for perception and to enhance the ability of an individual to respond accurately to a stimulus. However, it is unknown whether visual and auditory information contribute differentially to identify the direction and rotational motion of the stimulus. The purpose of this study was to determine the ability of an individual to accurately predict the direction and rotational motion of the stimulus based on visual and auditory information. In this study, we recruited 9 expert table-tennis players and used table-tennis service as our experimental model. Participants watched recorded services with different levels of visual and auditory information. The goal was to anticipate the direction of the service (left or right) and the rotational motion of service (topspin, sidespin, or cut). We recorded their responses and quantified the following outcomes: (i) directional accuracy and (ii) rotational motion accuracy. The response accuracy was the accurate predictions relative to the total number of trials. The ability of the participants to predict the direction of the service accurately increased with additional visual information but not with auditory information. In contrast, the ability of the participants to predict the rotational motion of the service accurately increased with the addition of auditory information to visual information but not with additional visual information alone. In conclusion, this finding demonstrates that visual information enhances the ability of an individual to accurately predict the direction of the stimulus, whereas additional auditory information enhances the ability of an individual to accurately predict the rotational motion of stimulus.

Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei.

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Tang, Yezhong; Christensen-Dalsgaard, Jakob; Carr, Catherine E

2012-06-01

We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of low to middle best-frequency fibers that bifurcate to project to both the NA and the nucleus magnocellularis (NM). The projection to NM formed large somatic terminals and bouton terminals. NM projected bilaterally to the second-order nucleus laminaris (NL), such that the ipsilateral projection innervated the dorsal NL neuropil, whereas the contralateral projection crossed the midline and innervated the ventral dendrites of NL neurons. Neurons in NL were generally bitufted, with dorsoventrally oriented dendrites. NL projected to the contralateral torus semicircularis and to the contralateral ventral superior olive (SOv). NA projected to ipsilateral dorsal superior olive (SOd), sent a major projection to the contralateral SOv, and projected to torus semicircularis. The SOd projected to the contralateral SOv, which projected back to the ipsilateral NM, NL, and NA. These results suggest homologous patterns of auditory connections in lizards and archosaurs but also different processing of low- and high-frequency information in the brainstem. Copyright © 2011 Wiley Periodicals, Inc.

Neurophysiologic intraoperative monitoring of the vestibulocochlear nerve.

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Simon, Mirela V

2011-12-01

Neurosurgical procedures involving the skull base and structures within can pose a significant risk of damage to the brain stem and cranial nerves. This can have life-threatening consequences and/or result in devastating neurologic deficits. Over the past decade, intraoperative neurophysiology has significantly evolved and currently offers a great tool for live monitoring of the integrity of nervous structures. Thus, dysfunction can be identified early and prompt modification of the surgical management or operating conditions, leads to avoidance of permanent structural damage.Along these lines, the vestibulocochlear nerve (CN VIII) and, to a greater extent, the auditory pathways as they pass through the brain stem are especially at risk during cerebelopontine angle (CPA), posterior/middle fossa, or brain stem surgery. CN VIII can be damaged by several mechanisms, from vascular compromise to mechanical injury by stretch, compression, dissection, and heat injury. Additionally, cochlea itself can be significantly damaged during temporal bone drilling, by noise, mechanical destruction, or infarction, and because of rupture, occlusion, or vasospasm of the internal auditory artery.CN VIII monitoring can be successfully achieved by live recording of the function of one of its parts, the cochlear or auditory nerve (AN), using the brain stem auditory evoked potentials (BAEPs), electrocochleography (ECochG), and compound nerve action potentials (CNAPs) of the cochlear nerve.This is a review of these techniques, their principle, applications, methodology, interpretation of the evoked responses, and their change from baseline, within the context of surgical and anesthesia environments, and finally the appropriate management of these changes.

Temporal and identity prediction in visual-auditory events: Electrophysiological evidence from stimulus omissions.

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van Laarhoven, Thijs; Stekelenburg, Jeroen J; Vroomen, Jean

2017-04-15

A rare omission of a sound that is predictable by anticipatory visual information induces an early negative omission response (oN1) in the EEG during the period of silence where the sound was expected. It was previously suggested that the oN1 was primarily driven by the identity of the anticipated sound. Here, we examined the role of temporal prediction in conjunction with identity prediction of the anticipated sound in the evocation of the auditory oN1. With incongruent audiovisual stimuli (a video of a handclap that is consistently combined with the sound of a car horn) we demonstrate in Experiment 1 that a natural match in identity between the visual and auditory stimulus is not required for inducing the oN1, and that the perceptual system can adapt predictions to unnatural stimulus events. In Experiment 2 we varied either the auditory onset (relative to the visual onset) or the identity of the sound across trials in order to hamper temporal and identity predictions. Relative to the natural stimulus with correct auditory timing and matching audiovisual identity, the oN1 was abolished when either the timing or the identity of the sound could not be predicted reliably from the video. Our study demonstrates the flexibility of the perceptual system in predictive processing (Experiment 1) and also shows that precise predictions of timing and content are both essential elements for inducing an oN1 (Experiment 2). Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of peripheral compression and auditory nerve fiber intensity coding using auditory steady-state responses

DEFF Research Database (Denmark)

Encina Llamas, Gerard; M. Harte, James; Epp, Bastian

2015-01-01

. Evaluation of these properties provides information about the health state of the system. It has been shown that a loss of outer hair cells leads to a reduction in peripheral compression. It has also recently been shown in animal studies that noise over-exposure, producing temporary threshold shifts, can....... The results indicate that the slope of the ASSR level growth function can be used to estimate peripheral compression simultaneously at four frequencies below 60 dB SPL, while the slope above 60 dB SPL may provide information about the integrity of intensity coding of low-SR fibers.......The compressive nonlinearity of the auditory system is assumed to be an epiphenomenon of a healthy cochlea and, particularly, of outer-hair cell function. Another ability of the healthy auditory system is to enable communication in acoustical environments with high-level background noises...

Magnetic resonance imaging of the internal auditory canal

International Nuclear Information System (INIS)

Daniels, D.L.; Herfkins, R.; Koehler, P.R.; Millen, S.J.; Shaffer, K.A.; Williams, A.L.; Haughton, V.M.

1984-01-01

Three patients with exclusively or predominantly intracanalicular neuromas and 5 with presumably normal internal auditory canals were examined with prototype 1.4- or 1.5-tesla magnetic resonance (MR) scanners. MR images showed the 7th and 8th cranial nerves in the internal auditory canal. The intracanalicular neuromas had larger diameter and slightly greater signal strength than the nerves. Early results suggest that minimal enlargement of the nerves can be detected even in the internal auditory canal

External auditory canal cholesteatoma and keratosis obturans: the role of imaging in preventing facial nerve injury.

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McCoul, Edward D; Hanson, Matthew B

2011-12-01

We conducted a retrospective study to compare the clinical characteristics of external auditory canal cholesteatoma (EACC) with those of a similar entity, keratosis obturans (KO). We also sought to identify those aspects of each disease that may lead to complications. We identified 6 patients in each group. Imaging studies were reviewed for evidence of bony erosion and the proximity of disease to vital structures. All 6 patients in the EACC group had their diagnosis confirmed by computed tomography (CT), which demonstrated widening of the bony external auditory canal; 4 of these patients had critical erosion of bone adjacent to the facial nerve. Of the 6 patients with KO, only 2 had undergone CT, and neither exhibited any significant bony erosion or expansion; 1 of them developed osteomyelitis of the temporal bone and adjacent temporomandibular joint. Another patient manifested KO as part of a dermatophytid reaction. The essential component of treatment in all cases of EACC was microscopic debridement of the ear canal. We conclude that EACC may produce significant erosion of bone with exposure of vital structures, including the facial nerve. Because of the clinical similarity of EACC to KO, misdiagnosis is possible. Temporal bone imaging should be obtained prior to attempts at debridement of suspected EACC. Increased awareness of these uncommon conditions is warranted to prompt appropriate investigation and prevent iatrogenic complications such as facial nerve injury.

Effects on auditory-nerve fibers of opening the otic capsule at the apex of the chinchilla cochlea

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Recio-Spinoso, Alberto; Temchin, Andrei N.; Ruggero, Mario A.

2015-12-01

Vibration responses to clicks measured at the apex of chinchilla cochleae with open otic capsules have onsets much shorter than those of responses of auditory-nerve fibers (ANFs) corrected for synaptic and neural delays. Apical vibration responses to tones in open cochleae also differ in other respects from the responses to tones of ANFs with low characteristic frequency (CF) in normal chinchilla cochleae. To further specify the origin(s) of these differences, we recorded from chinchilla ANFs after delicately opening a small hole in the otic capsule overlying scala vestibuli in the cochlear apex. In those cochleae, the earliest ANF responses to clicks are often evoked by condensation (rather than rarefaction) clicks and responses to tones often exhibit level-dependent phase changes different from those in normal cochleae. These findings are largely consistent with, and seem to account for, apical vibration responses of cochleae with open otic capsules. An unexpected finding is that the tuning curves of ANFs with moderately high CF and normal CF thresholds often had hypersensitive tails.

Fast negative feedback enables mammalian auditory nerve fibers to encode a wide dynamic range of sound intensities.

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Mark Ospeck

Full Text Available Mammalian auditory nerve fibers (ANF are remarkable for being able to encode a 40 dB, or hundred fold, range of sound pressure levels into their firing rate. Most of the fibers are very sensitive and raise their quiescent spike rate by a small amount for a faint sound at auditory threshold. Then as the sound intensity is increased, they slowly increase their spike rate, with some fibers going up as high as ∼300 Hz. In this way mammals are able to combine sensitivity and wide dynamic range. They are also able to discern sounds embedded within background noise. ANF receive efferent feedback, which suggests that the fibers are readjusted according to the background noise in order to maximize the information content of their auditory spike trains. Inner hair cells activate currents in the unmyelinated distal dendrites of ANF where sound intensity is rate-coded into action potentials. We model this spike generator compartment as an attenuator that employs fast negative feedback. Input current induces rapid and proportional leak currents. This way ANF are able to have a linear frequency to input current (f-I curve that has a wide dynamic range. The ANF spike generator remains very sensitive to threshold currents, but efferent feedback is able to lower its gain in response to noise.

(A)musicality in Williams syndrome: examining relationships among auditory perception, musical skill, and emotional responsiveness to music.

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Lense, Miriam D; Shivers, Carolyn M; Dykens, Elisabeth M

2013-01-01

Williams syndrome (WS), a genetic, neurodevelopmental disorder, is of keen interest to music cognition researchers because of its characteristic auditory sensitivities and emotional responsiveness to music. However, actual musical perception and production abilities are more variable. We examined musicality in WS through the lens of amusia and explored how their musical perception abilities related to their auditory sensitivities, musical production skills, and emotional responsiveness to music. In our sample of 73 adolescents and adults with WS, 11% met criteria for amusia, which is higher than the 4% prevalence rate reported in the typically developing (TD) population. Amusia was not related to auditory sensitivities but was related to musical training. Performance on the amusia measure strongly predicted musical skill but not emotional responsiveness to music, which was better predicted by general auditory sensitivities. This study represents the first time amusia has been examined in a population with a known neurodevelopmental genetic disorder with a range of cognitive abilities. Results have implications for the relationships across different levels of auditory processing, musical skill development, and emotional responsiveness to music, as well as the understanding of gene-brain-behavior relationships in individuals with WS and TD individuals with and without amusia.

(Amusicality in Williams syndrome: Examining relationships among auditory perception, musical skill, and emotional responsiveness to music

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Miriam eLense

2013-08-01

Full Text Available Williams syndrome (WS, a genetic, neurodevelopmental disorder, is of keen interest to music cognition researchers because of its characteristic auditory sensitivities and emotional responsiveness to music. However, actual musical perception and production abilities are more variable. We examined musicality in WS through the lens of amusia and explored how their musical perception abilities related to their auditory sensitivities, musical production skills, and emotional responsiveness to music. In our sample of 73 adolescents and adults with WS, 11% met criteria for amusia, which is higher than the 4% prevalence rate reported in the typically developing population. Amusia was not related to auditory sensitivities but was related to musical training. Performance on the amusia measure strongly predicted musical skill but not emotional responsiveness to music, which was better predicted by general auditory sensitivities. This study represents the first time amusia has been examined in a population with a known neurodevelopmental genetic disorder with a range of cognitive abilities. Results have implications for the relationships across different levels of auditory processing, musical skill development, and emotional responsiveness to music, as well as the understanding of gene-brain-behavior relationships in individuals with WS and typically developing individuals with and without amusia.

Speech Evoked Auditory Brainstem Response in Stuttering

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Ali Akbar Tahaei

2014-01-01

Full Text Available Auditory processing deficits have been hypothesized as an underlying mechanism for stuttering. Previous studies have demonstrated abnormal responses in subjects with persistent developmental stuttering (PDS at the higher level of the central auditory system using speech stimuli. Recently, the potential usefulness of speech evoked auditory brainstem responses in central auditory processing disorders has been emphasized. The current study used the speech evoked ABR to investigate the hypothesis that subjects with PDS have specific auditory perceptual dysfunction. Objectives. To determine whether brainstem responses to speech stimuli differ between PDS subjects and normal fluent speakers. Methods. Twenty-five subjects with PDS participated in this study. The speech-ABRs were elicited by the 5-formant synthesized syllable/da/, with duration of 40 ms. Results. There were significant group differences for the onset and offset transient peaks. Subjects with PDS had longer latencies for the onset and offset peaks relative to the control group. Conclusions. Subjects with PDS showed a deficient neural timing in the early stages of the auditory pathway consistent with temporal processing deficits and their abnormal timing may underlie to their disfluency.

Imaging of the facial nerve

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Veillon, F. [Service de Radiologie I, Hopital de Hautepierre, 67098 Strasbourg Cedex (France)], E-mail: Francis.Veillon@chru-strasbourg.fr; Ramos-Taboada, L.; Abu-Eid, M. [Service de Radiologie I, Hopital de Hautepierre, 67098 Strasbourg Cedex (France); Charpiot, A. [Service d' ORL, Hopital de Hautepierre, 67098 Strasbourg Cedex (France); Riehm, S. [Service de Radiologie I, Hopital de Hautepierre, 67098 Strasbourg Cedex (France)

2010-05-15

The facial nerve is responsible for the motor innervation of the face. It has a visceral motor function (lacrimal, submandibular, sublingual glands and secretion of the nose); it conveys a great part of the taste fibers, participates to the general sensory of the auricle (skin of the concha) and the wall of the external auditory meatus. The facial mimic, production of tears, nasal flow and salivation all depend on the facial nerve. In order to image the facial nerve it is mandatory to be knowledgeable about its normal anatomy including the course of its efferent and afferent fibers and about relevant technical considerations regarding CT and MR to be able to achieve high-resolution images of the nerve.

(A)musicality in Williams syndrome: examining relationships among auditory perception, musical skill, and emotional responsiveness to music

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Lense, Miriam D.; Shivers, Carolyn M.; Dykens, Elisabeth M.

2013-01-01

Williams syndrome (WS), a genetic, neurodevelopmental disorder, is of keen interest to music cognition researchers because of its characteristic auditory sensitivities and emotional responsiveness to music. However, actual musical perception and production abilities are more variable. We examined musicality in WS through the lens of amusia and explored how their musical perception abilities related to their auditory sensitivities, musical production skills, and emotional responsiveness to music. In our sample of 73 adolescents and adults with WS, 11% met criteria for amusia, which is higher than the 4% prevalence rate reported in the typically developing (TD) population. Amusia was not related to auditory sensitivities but was related to musical training. Performance on the amusia measure strongly predicted musical skill but not emotional responsiveness to music, which was better predicted by general auditory sensitivities. This study represents the first time amusia has been examined in a population with a known neurodevelopmental genetic disorder with a range of cognitive abilities. Results have implications for the relationships across different levels of auditory processing, musical skill development, and emotional responsiveness to music, as well as the understanding of gene-brain-behavior relationships in individuals with WS and TD individuals with and without amusia. PMID:23966965

Intraoperative Electrocochleographic Characteristics of Auditory Neuropathy Spectrum Disorder in Cochlear Implant Subjects

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William J. Riggs

2017-07-01

Full Text Available Auditory neuropathy spectrum disorder (ANSD is characterized by an apparent discrepancy between measures of cochlear and neural function based on auditory brainstem response (ABR testing. Clinical indicators of ANSD are a present cochlear microphonic (CM with small or absent wave V. Many identified ANSD patients have speech impairment severe enough that cochlear implantation (CI is indicated. To better understand the cochleae identified with ANSD that lead to a CI, we performed intraoperative round window electrocochleography (ECochG to tone bursts in children (n = 167 and adults (n = 163. Magnitudes of the responses to tones of different frequencies were summed to measure the “total response” (ECochG-TR, a metric often dominated by hair cell activity, and auditory nerve activity was estimated visually from the compound action potential (CAP and auditory nerve neurophonic (ANN as a ranked “Nerve Score”. Subjects identified as ANSD (45 ears in children, 3 in adults had higher values of ECochG-TR than adult and pediatric subjects also receiving CIs not identified as ANSD. However, nerve scores of the ANSD group were similar to the other cohorts, although dominated by the ANN to low frequencies more than in the non-ANSD groups. To high frequencies, the common morphology of ANSD cases was a large CM and summating potential, and small or absent CAP. Common morphologies in other groups were either only a CM, or a combination of CM and CAP. These results indicate that responses to high frequencies, derived primarily from hair cells, are the main source of the CM used to evaluate ANSD in the clinical setting. However, the clinical tests do not capture the wide range of neural activity seen to low frequency sounds.

Reference-Free Assessment of Speech Intelligibility Using Bispectrum of an Auditory Neurogram

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Hossain, Mohammad E.; Jassim, Wissam A.; Zilany, Muhammad S. A.

2016-01-01

Sensorineural hearing loss occurs due to damage to the inner and outer hair cells of the peripheral auditory system. Hearing loss can cause decreases in audibility, dynamic range, frequency and temporal resolution of the auditory system, and all of these effects are known to affect speech intelligibility. In this study, a new reference-free speech intelligibility metric is proposed using 2-D neurograms constructed from the output of a computational model of the auditory periphery. The responses of the auditory-nerve fibers with a wide range of characteristic frequencies were simulated to construct neurograms. The features of the neurograms were extracted using third-order statistics referred to as bispectrum. The phase coupling of neurogram bispectrum provides a unique insight for the presence (or deficit) of supra-threshold nonlinearities beyond audibility for listeners with normal hearing (or hearing loss). The speech intelligibility scores predicted by the proposed method were compared to the behavioral scores for listeners with normal hearing and hearing loss both in quiet and under noisy background conditions. The results were also compared to the performance of some existing methods. The predicted results showed a good fit with a small error suggesting that the subjective scores can be estimated reliably using the proposed neural-response-based metric. The proposed metric also had a wide dynamic range, and the predicted scores were well-separated as a function of hearing loss. The proposed metric successfully captures the effects of hearing loss and supra-threshold nonlinearities on speech intelligibility. This metric could be applied to evaluate the performance of various speech-processing algorithms designed for hearing aids and cochlear implants. PMID:26967160

Super-response to cardiac resynchronization therapy may predict late phrenic nerve stimulation.

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Juliá, Justo; López-Gil, María; Fontenla, Adolfo; Lozano, Álvaro; Villagraz, Lola; Salguero, Rafael; Arribas, Fernando

2017-11-22

Changes in the anatomical relationship between left phrenic nerve and coronary veins may occur due to the reverse remodelling observed in super-responders to cardiac resynchronization therapy (CRT) and might be the underlying mechanism in patients developing late-onset phrenic nerve stimulation (PNS) without evidence of lead dislodgement (LD). In this study, we sought to evaluate the role of super-response (SR) to CRT as a potential predictor of late-onset PNS. Consecutive patients implanted with a left ventricular (LV) lead in a single centre were retrospectively analysed. Phrenic nerve stimulation was classified as 'early' when it occurred within 3 months of implantation and 'late' for occurrences thereafter. 'Late' PNS was considered related to LD (LD-PNS) when LV threshold differed by > 1 V or impedance >250 Ω from baseline values or in case of radiological displacement. Cases not meeting the former criteria were classified as 'non-LD-PNS'. Super-response was defined as a decrease ≥30% of the left ventricluar end-systolic volume at 1-year echocardiography. At 32 ± 7 months follow-up, PNS occurred in 20 of 139 patients. Late non-LD-PNS incidence was significantly higher in the SR group (8/61; 13.1%) when compared with the non-SR (1/78; 1.3%) (P = 0.010). Super-response remained the only predictor of non-LD-PNS at multivariate analysis (odds ratio: 11.62, 95% confidence interval 1.41-95.68, P = 0.023). Incidence of late non-LD-PNS is higher among SR to CRT, suggesting a potential role of the changes in the anatomical relationship between left phrenic nerve and coronary veins. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Weak responses to auditory feedback perturbation during articulation in persons who stutter: evidence for abnormal auditory-motor transformation.

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Shanqing Cai

Full Text Available Previous empirical observations have led researchers to propose that auditory feedback (the auditory perception of self-produced sounds when speaking functions abnormally in the speech motor systems of persons who stutter (PWS. Researchers have theorized that an important neural basis of stuttering is the aberrant integration of auditory information into incipient speech motor commands. Because of the circumstantial support for these hypotheses and the differences and contradictions between them, there is a need for carefully designed experiments that directly examine auditory-motor integration during speech production in PWS. In the current study, we used real-time manipulation of auditory feedback to directly investigate whether the speech motor system of PWS utilizes auditory feedback abnormally during articulation and to characterize potential deficits of this auditory-motor integration. Twenty-one PWS and 18 fluent control participants were recruited. Using a short-latency formant-perturbation system, we examined participants' compensatory responses to unanticipated perturbation of auditory feedback of the first formant frequency during the production of the monophthong [ε]. The PWS showed compensatory responses that were qualitatively similar to the controls' and had close-to-normal latencies (∼150 ms, but the magnitudes of their responses were substantially and significantly smaller than those of the control participants (by 47% on average, p<0.05. Measurements of auditory acuity indicate that the weaker-than-normal compensatory responses in PWS were not attributable to a deficit in low-level auditory processing. These findings are consistent with the hypothesis that stuttering is associated with functional defects in the inverse models responsible for the transformation from the domain of auditory targets and auditory error information into the domain of speech motor commands.

Effects of Caffeine on Auditory Brainstem Response

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Saleheh Soleimanian

2008-06-01

Full Text Available Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR.Materials and Methods: In this clinical trial study 43 normal 18-25 years old male students were participated. The subjects consumed 0, 2 and 3 mg/kg BW caffeine in three different sessions. Auditory brainstem responses were recorded before and 30 minute after caffeine consumption. The results were analyzed by Friedman and Wilcoxone test to assess the effects of caffeine on auditory brainstem response.Results: Compared to control group the latencies of waves III,V and I-V interpeak interval of the cases decreased significantly after 2 and 3mg/kg BW caffeine consumption. Wave I latency significantly decreased after 3mg/kg BW caffeine consumption(p<0.01. Conclusion: Increasing of the glutamate level resulted from the adenosine receptor blocking brings about changes in conduction in the central auditory pathway.

Predictive uncertainty in auditory sequence processing

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Niels Chr. eHansen

2014-09-01

Full Text Available Previous studies of auditory expectation have focused on the expectedness perceived by listeners retrospectively in response to events. In contrast, this research examines predictive uncertainty - a property of listeners’ prospective state of expectation prior to the onset of an event. We examine the information-theoretic concept of Shannon entropy as a model of predictive uncertainty in music cognition. This is motivated by the Statistical Learning Hypothesis, which proposes that schematic expectations reflect probabilistic relationships between sensory events learned implicitly through exposure.Using probability estimates from an unsupervised, variable-order Markov model, 12 melodic contexts high in entropy and 12 melodic contexts low in entropy were selected from two musical repertoires differing in structural complexity (simple and complex. Musicians and non-musicians listened to the stimuli and provided explicit judgments of perceived uncertainty (explicit uncertainty. We also examined an indirect measure of uncertainty computed as the entropy of expectedness distributions obtained using a classical probe-tone paradigm where listeners rated the perceived expectedness of the final note in a melodic sequence (inferred uncertainty. Finally, we simulate listeners’ perception of expectedness and uncertainty using computational models of auditory expectation. A detailed model comparison indicates which model parameters maximize fit to the data and how they compare to existing models in the literature.The results show that listeners experience greater uncertainty in high-entropy musical contexts than low-entropy contexts. This effect is particularly apparent for inferred uncertainty and is stronger in musicians than non-musicians. Consistent with the Statistical Learning Hypothesis, the results suggest that increased domain-relevant training is associated with an increasingly accurate cognitive model of probabilistic structure in music.

Predictive uncertainty in auditory sequence processing.

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Hansen, Niels Chr; Pearce, Marcus T

2014-01-01

Previous studies of auditory expectation have focused on the expectedness perceived by listeners retrospectively in response to events. In contrast, this research examines predictive uncertainty-a property of listeners' prospective state of expectation prior to the onset of an event. We examine the information-theoretic concept of Shannon entropy as a model of predictive uncertainty in music cognition. This is motivated by the Statistical Learning Hypothesis, which proposes that schematic expectations reflect probabilistic relationships between sensory events learned implicitly through exposure. Using probability estimates from an unsupervised, variable-order Markov model, 12 melodic contexts high in entropy and 12 melodic contexts low in entropy were selected from two musical repertoires differing in structural complexity (simple and complex). Musicians and non-musicians listened to the stimuli and provided explicit judgments of perceived uncertainty (explicit uncertainty). We also examined an indirect measure of uncertainty computed as the entropy of expectedness distributions obtained using a classical probe-tone paradigm where listeners rated the perceived expectedness of the final note in a melodic sequence (inferred uncertainty). Finally, we simulate listeners' perception of expectedness and uncertainty using computational models of auditory expectation. A detailed model comparison indicates which model parameters maximize fit to the data and how they compare to existing models in the literature. The results show that listeners experience greater uncertainty in high-entropy musical contexts than low-entropy contexts. This effect is particularly apparent for inferred uncertainty and is stronger in musicians than non-musicians. Consistent with the Statistical Learning Hypothesis, the results suggest that increased domain-relevant training is associated with an increasingly accurate cognitive model of probabilistic structure in music.

Evaluation of peripheral auditory pathways and brainstem in obstructive sleep apnea

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Erika Matsumura

Full Text Available Abstract Introduction Obstructive sleep apnea causes changes in normal sleep architecture, fragmenting it chronically with intermittent hypoxia, leading to serious health consequences in the long term. It is believed that the occurrence of respiratory events during sleep, such as apnea and hypopnea, can impair the transmission of nerve impulses along the auditory pathway that are highly dependent on the supply of oxygen. However, this association is not well established in the literature. Objective To compare the evaluation of peripheral auditory pathway and brainstem among individuals with and without obstructive sleep apnea. Methods The sample consisted of 38 adult males, mean age of 35.8 (±7.2, divided into four groups matched for age and Body Mass Index. The groups were classified based on polysomnography in: control (n = 10, mild obstructive sleep apnea (n = 11 moderate obstructive sleep apnea (n = 8 and severe obstructive sleep apnea (n = 9. All study subjects denied a history of risk for hearing loss and underwent audiometry, tympanometry, acoustic reflex and Brainstem Auditory Evoked Response. Statistical analyses were performed using three-factor ANOVA, 2-factor ANOVA, chi-square test, and Fisher's exact test. The significance level for all tests was 5%. Results There was no difference between the groups for hearing thresholds, tympanometry and evaluated Brainstem Auditory Evoked Response parameters. An association was observed between the presence of obstructive sleep apnea and changes in absolute latency of wave V (p = 0.03. There was an association between moderate obstructive sleep apnea and change of the latency of wave V (p = 0.01. Conclusion The presence of obstructive sleep apnea is associated with changes in nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The increase in obstructive sleep apnea severity does not promote worsening of responses assessed by audiometry, tympanometry and Brainstem

Great Expectations: Is there Evidence for Predictive Coding in Auditory Cortex?

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Heilbron, Micha; Chait, Maria

2017-08-04

Predictive coding is possibly one of the most influential, comprehensive, and controversial theories of neural function. While proponents praise its explanatory potential, critics object that key tenets of the theory are untested or even untestable. The present article critically examines existing evidence for predictive coding in the auditory modality. Specifically, we identify five key assumptions of the theory and evaluate each in the light of animal, human and modeling studies of auditory pattern processing. For the first two assumptions - that neural responses are shaped by expectations and that these expectations are hierarchically organized - animal and human studies provide compelling evidence. The anticipatory, predictive nature of these expectations also enjoys empirical support, especially from studies on unexpected stimulus omission. However, for the existence of separate error and prediction neurons, a key assumption of the theory, evidence is lacking. More work exists on the proposed oscillatory signatures of predictive coding, and on the relation between attention and precision. However, results on these latter two assumptions are mixed or contradictory. Looking to the future, more collaboration between human and animal studies, aided by model-based analyses will be needed to test specific assumptions and implementations of predictive coding - and, as such, help determine whether this popular grand theory can fulfill its expectations. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Temporal envelope processing in the human auditory cortex: response and interconnections of auditory cortical areas.

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Gourévitch, Boris; Le Bouquin Jeannès, Régine; Faucon, Gérard; Liégeois-Chauvel, Catherine

2008-03-01

Temporal envelope processing in the human auditory cortex has an important role in language analysis. In this paper, depth recordings of local field potentials in response to amplitude modulated white noises were used to design maps of activation in primary, secondary and associative auditory areas and to study the propagation of the cortical activity between them. The comparison of activations between auditory areas was based on a signal-to-noise ratio associated with the response to amplitude modulation (AM). The functional connectivity between cortical areas was quantified by the directed coherence (DCOH) applied to auditory evoked potentials. This study shows the following reproducible results on twenty subjects: (1) the primary auditory cortex (PAC), the secondary cortices (secondary auditory cortex (SAC) and planum temporale (PT)), the insular gyrus, the Brodmann area (BA) 22 and the posterior part of T1 gyrus (T1Post) respond to AM in both hemispheres. (2) A stronger response to AM was observed in SAC and T1Post of the left hemisphere independent of the modulation frequency (MF), and in the left BA22 for MFs 8 and 16Hz, compared to those in the right. (3) The activation and propagation features emphasized at least four different types of temporal processing. (4) A sequential activation of PAC, SAC and BA22 areas was clearly visible at all MFs, while other auditory areas may be more involved in parallel processing upon a stream originating from primary auditory area, which thus acts as a distribution hub. These results suggest that different psychological information is carried by the temporal envelope of sounds relative to the rate of amplitude modulation.

Renal Nerve Stimulation-Induced Blood Pressure Changes Predict Ambulatory Blood Pressure Response After Renal Denervation.

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de Jong, Mark R; Adiyaman, Ahmet; Gal, Pim; Smit, Jaap Jan J; Delnoy, Peter Paul H M; Heeg, Jan-Evert; van Hasselt, Boudewijn A A M; Lau, Elizabeth O Y; Persu, Alexandre; Staessen, Jan A; Ramdat Misier, Anand R; Steinberg, Jonathan S; Elvan, Arif

2016-09-01

Blood pressure (BP) response to renal denervation (RDN) is highly variable and its effectiveness debated. A procedural end point for RDN may improve consistency of response. The objective of the current analysis was to look for the association between renal nerve stimulation (RNS)-induced BP increase before and after RDN and changes in ambulatory BP monitoring (ABPM) after RDN. Fourteen patients with drug-resistant hypertension referred for RDN were included. RNS was performed under general anesthesia at 4 sites in the right and left renal arteries, both before and immediately after RDN. RNS-induced BP changes were monitored and correlated to changes in ambulatory BP at a follow-up of 3 to 6 months after RDN. RNS resulted in a systolic BP increase of 50±27 mm Hg before RDN and systolic BP increase of 13±16 mm Hg after RDN (Pefficacy of RDN and predict BP response to RDN. © 2016 American Heart Association, Inc.

Auditory brainstem activity and development evoked by apical versus basal cochlear implant electrode stimulation in children.

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Gordon, K A; Papsin, B C; Harrison, R V

2007-08-01

The role of apical versus basal cochlear implant electrode stimulation on central auditory development was examined. We hypothesized that, in children with early onset deafness, auditory development evoked by basal electrode stimulation would differ from that evoked more apically. Responses of the auditory nerve and brainstem, evoked by an apical and a basal implant electrode, were measured over the first year of cochlear implant use in 50 children with early onset severe to profound deafness who used hearing aids prior to implantation. Responses at initial stimulation were of larger amplitude and shorter latency when evoked by the apical electrode. No significant effects of residual hearing or age were found on initial response amplitudes or latencies. With implant use, responses evoked by both electrodes showed decreases in wave and interwave latencies reflecting decreased neural conduction time through the brainstem. Apical versus basal differences persisted with implant experience with one exception; eIII-eV interlatency differences decreased with implant use. Acute stimulation shows prolongation of basally versus apically evoked auditory nerve and brainstem responses in children with severe to profound deafness. Interwave latencies reflecting neural conduction along the caudal and rostral portions of the brainstem decreased over the first year of implant use. Differences in neural conduction times evoked by apical versus basal electrode stimulation persisted in the caudal but not rostral brainstem. Activity-dependent changes of the auditory brainstem occur in response to both apical and basal cochlear implant electrode stimulation.

Category-specific responses to faces and objects in primate auditory cortex

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Kari L Hoffman

2008-03-01

Full Text Available Auditory and visual signals often occur together, and the two sensory channels are known to infl uence each other to facilitate perception. The neural basis of this integration is not well understood, although other forms of multisensory infl uences have been shown to occur at surprisingly early stages of processing in cortex. Primary visual cortex neurons can show frequency-tuning to auditory stimuli, and auditory cortex responds selectively to certain somatosensory stimuli, supporting the possibility that complex visual signals may modulate early stages of auditory processing. To elucidate which auditory regions, if any, are responsive to complex visual stimuli, we recorded from auditory cortex and the superior temporal sulcus while presenting visual stimuli consisting of various objects, neutral faces, and facial expressions generated during vocalization. Both objects and conspecifi c faces elicited robust fi eld potential responses in auditory cortex sites, but the responses varied by category: both neutral and vocalizing faces had a highly consistent negative component (N100 followed by a broader positive component (P180 whereas object responses were more variable in time and shape, but could be discriminated consistently from the responses to faces. The face response did not vary within the face category, i.e., for expressive vs. neutral face stimuli. The presence of responses for both objects and neutral faces suggests that auditory cortex receives highly informative visual input that is not restricted to those stimuli associated with auditory components. These results reveal selectivity for complex visual stimuli in a brain region conventionally described as non-visual unisensory cortex.

Non-tip auditory-nerve responses that are suppressed by low-frequency bias tones originate from reticular lamina motion.

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Nam, Hui; Guinan, John J

2017-12-14

Recent cochlear mechanical measurements show that active processes increase the motion response of the reticular lamina (RL) at frequencies more than an octave below the local characteristic frequency (CF) for CFs above 5 kHz. A possible correlate is that in high-CF (>5 kHz) auditory-nerve (AN) fibers, responses to frequencies 1-3 octaves below CF ("tail" frequencies) can be inhibited by medial olivocochlear (MOC) efferents. These results indicate that active processes enhance the sensitivity of tail-frequency RL and AN responses. Perhaps related is that some apical low-CF AN fibers have tuning-curve (TC) "side-lobe" response areas at frequencies above and below the TC-tip that are MOC inhibited. We hypothesized that the tail and side-lobe responses are enhanced by the same active mechanisms as CF cochlear amplification. If responses to CF, tail-frequency, and TC-side-lobe tones are all enhanced by prestin motility controlled by outer-hair-cell (OHC) transmembrane voltage, then they should depend on OHC stereocilia position in the same way. To test this, we cyclically changed the OHC-stereocilia mechano-electric-transduction (MET) operating point with low-frequency "bias" tones (BTs) and increased the BT level until the BT caused quasi-static OHC MET saturation that reduced or "suppressed" the gain of OHC active processes. While measuring cat AN-fiber responses, 50 Hz BT level series, 70-120 dB SPL, were run alone and with CF tones, or 2.5 kHz tail-frequency tones, or side-lobe tones. BT-tone-alone responses were used to exclude BT sound levels that produced AN responses that might obscure BT suppression. Data were analyzed to show the BT phase that suppressed the tone responses at the lowest sound level. We found that AN responses to CF, tail-frequency, and side-lobe tones were suppressed at the same BT phase in almost all cases. The data are consistent with the enhancement of responses to CF, tail-frequency, and side-lobe tones all being due to the same

Waveform efficiency analysis of auditory nerve fiber stimulation for cochlear implants

International Nuclear Information System (INIS)

Navaii, Mehdi Lotfi; Sadhedi, Hamed; Jalali, Mohsen

2013-01-01

Evaluation of the electrical stimulation efficiency of various stimulating waveforms is an important issue for efficient neural stimulator design. Concerning the implantable micro devices design, it is also necessary to consider the feasibility of hardware implementation of the desired waveforms. In this paper, the charge, power and energy efficiency of four waveforms (i.e. square, rising ramp, triangular and rising ramp-decaying exponential) in various durations have been simulated and evaluated based on the computational model of the auditory nerve fibers. Moreover, for a fair comparison of their feasibility, a fully integrated current generator circuit has been developed so that the desired stimulating waveforms can be generated. The simulation results show that stimulation with the square waveforms is a proper choice in short and intermediate durations while the rising ramp-decaying exponential or triangular waveforms can be employed for long durations.

Conductive Hearing Loss Has Long-Lasting Structural and Molecular Effects on Presynaptic and Postsynaptic Structures of Auditory Nerve Synapses in the Cochlear Nucleus.

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Clarkson, Cheryl; Antunes, Flora M; Rubio, Maria E

2016-09-28

Sound deprivation by conductive hearing loss increases hearing thresholds, but little is known about the response of the auditory brainstem during and after conductive hearing loss. Here, we show in young adult rats that 10 d of monaural conductive hearing loss (i.e., earplugging) leads to hearing deficits that persist after sound levels are restored. Hearing thresholds in response to clicks and frequencies higher than 8 kHz remain increased after a 10 d recovery period. Neural output from the cochlear nucleus measured at 10 dB above threshold is reduced and followed by an overcompensation at the level of the lateral lemniscus. We assessed whether structural and molecular substrates at auditory nerve (endbulb of Held) synapses in the cochlear nucleus could explain these long-lasting changes in hearing processing. During earplugging, vGluT1 expression in the presynaptic terminal decreased and synaptic vesicles were smaller. Together, there was an increase in postsynaptic density (PSD) thickness and an upregulation of GluA3 AMPA receptor subunits on bushy cells. After earplug removal and a 10 d recovery period, the density of synaptic vesicles increased, vesicles were also larger, and the PSD of endbulb synapses was larger and thicker. The upregulation of the GluA3 AMPAR subunit observed during earplugging was maintained after the recovery period. This suggests that GluA3 plays a role in plasticity in the cochlear nucleus. Our study demonstrates that sound deprivation has long-lasting alterations on structural and molecular presynaptic and postsynaptic components at the level of the first auditory nerve synapse in the auditory brainstem. Despite being the second most prevalent form of hearing loss, conductive hearing loss and its effects on central synapses have received relatively little attention. Here, we show that 10 d of monaural conductive hearing loss leads to an increase in hearing thresholds, to an increased central gain upstream of the cochlear nucleus at

Using excitation patterns to predict auditory masking

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Heijden, van der M.L.; Kohlrausch, A.G.

1992-01-01

We investigated how well auditory masking can be predicted from excitation patterns. For this purpose, a quantitative model proposed by Moore and Glasberg (1987) and Glasberg and Moore (1990) was used to calculate excitation patterns evoked by stationary sounds. We performed simulations of a number

Can preoperative MR imaging predict optic nerve invasion of retinoblastoma?

International Nuclear Information System (INIS)

Song, Kyoung Doo; Eo, Hong; Kim, Ji Hye; Yoo, So-Young; Jeon, Tae Yeon

2012-01-01

Purpose: To evaluate the accuracy of pre-operative MRI for the detection of optic nerve invasion in retinoblastoma. Materials and methods: Institutional review board approval and informed consent were waived for this retrospective study. A total of 41 patients were included. Inclusion criteria were histologically proven retinoblastoma, availability of diagnostic-quality preoperative MR images acquired during the 4 weeks before surgery, unilateral retinoblastoma, and normal-sized optic nerve. Two radiologists retrospectively reviewed the MR images independently. Five imaging findings (diffuse mild optic nerve enhancement, focal strong optic nerve enhancement, optic sheath enhancement, tumor location, and tumor size) were evaluated against optic nerve invasion of retinoblastoma. The predictive performance of all MR imaging findings for optic nerve invasion was also evaluated by the receiver operating characteristic curve analysis. Results: Optic nerve invasion was histopathologically confirmed in 24% of study population (10/41). The differences in diffuse mild enhancement, focal strong enhancement, optic sheath enhancement, and tumor location between patients with optic nerve invasion and patients without optic nerve invasion were not significant. Tumor sizes were 16.1 mm (SD: 2.2 mm) and 14.9 mm (SD: 3.6 mm) in patients with and without optic nerve involvement, respectively (P = 0.444). P-Values from binary logistic regression indicated that all five imaging findings were not significant predictors of tumor invasion of optic nerve. The AUC values of all MR imaging findings for the prediction of optic nerve invasion were 0.689 (95% confidence interval: 0.499–0.879) and 0.653 (95% confidence interval: 0.445–0.861) for observer 1 and observer 2, respectively. Conclusion: Findings of MRI in patients with normal-sized optic nerves have limited usefulness in preoperatively predicting the presence of optic nerve invasion in retinoblastoma.

Can preoperative MR imaging predict optic nerve invasion of retinoblastoma?

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Song, Kyoung Doo, E-mail: kdsong0308@gmail.com [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Eo, Hong, E-mail: rtombow@gmail.com [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Kim, Ji Hye, E-mail: jhkate.kim@samsung.com [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Yoo, So-Young, E-mail: sy1131.yoo@samsung.com [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of); Jeon, Tae Yeon, E-mail: hathor97.jeon@samsung.com [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710 (Korea, Republic of)

2012-12-15

Purpose: To evaluate the accuracy of pre-operative MRI for the detection of optic nerve invasion in retinoblastoma. Materials and methods: Institutional review board approval and informed consent were waived for this retrospective study. A total of 41 patients were included. Inclusion criteria were histologically proven retinoblastoma, availability of diagnostic-quality preoperative MR images acquired during the 4 weeks before surgery, unilateral retinoblastoma, and normal-sized optic nerve. Two radiologists retrospectively reviewed the MR images independently. Five imaging findings (diffuse mild optic nerve enhancement, focal strong optic nerve enhancement, optic sheath enhancement, tumor location, and tumor size) were evaluated against optic nerve invasion of retinoblastoma. The predictive performance of all MR imaging findings for optic nerve invasion was also evaluated by the receiver operating characteristic curve analysis. Results: Optic nerve invasion was histopathologically confirmed in 24% of study population (10/41). The differences in diffuse mild enhancement, focal strong enhancement, optic sheath enhancement, and tumor location between patients with optic nerve invasion and patients without optic nerve invasion were not significant. Tumor sizes were 16.1 mm (SD: 2.2 mm) and 14.9 mm (SD: 3.6 mm) in patients with and without optic nerve involvement, respectively (P = 0.444). P-Values from binary logistic regression indicated that all five imaging findings were not significant predictors of tumor invasion of optic nerve. The AUC values of all MR imaging findings for the prediction of optic nerve invasion were 0.689 (95% confidence interval: 0.499–0.879) and 0.653 (95% confidence interval: 0.445–0.861) for observer 1 and observer 2, respectively. Conclusion: Findings of MRI in patients with normal-sized optic nerves have limited usefulness in preoperatively predicting the presence of optic nerve invasion in retinoblastoma.

Intracranial pressure-induced optic nerve sheath response as a predictive biomarker for optic disc edema in astronauts.

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Wostyn, Peter; De Deyn, Peter Paul

2017-11-01

A significant proportion of the astronauts who spend extended periods in microgravity develop ophthalmic abnormalities. Understanding this syndrome, called visual impairment and intracranial pressure (VIIP), has become a high priority for National Aeronautics and Space Administration, especially in view of future long-duration missions (e.g., Mars missions). Moreover, to ensure selection of astronaut candidates who will be able to complete long-duration missions with low risk of the VIIP syndrome, it is imperative to identify biomarkers for VIIP risk prediction. Here, we hypothesize that the optic nerve sheath response to alterations in intracranial pressure may be a potential predictive biomarker for optic disc edema in astronauts. If confirmed, this biomarker could be used for preflight identification of astronauts at risk for developing VIIP-associated optic disc edema.

Malformation of the eighth cranial nerve in children.

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de Paula-Vernetta, Carlos; Muñoz-Fernández, Noelia; Mas-Estellés, Fernando; Guzmán-Calvete, Abel; Cavallé-Garrido, Laura; Morera-Pérez, Constantino

2016-01-01

Prevalence of congenital sensorineural hearing loss (SNHL) is approximately 1.5-6 in every 1,000 newborns. Dysfunction of the auditory nerve (auditory neuropathy) may be involved in up to 1%-10% of cases; hearing losses because of vestibulocochlear nerve (VCN) aplasia are less frequent. The objectives of this study were to describe clinical manifestations, hearing thresholds and aetiology of children with SNHL and VCN aplasia. We present 34 children (mean age 20 months) with auditory nerve malformation and profound HL taken from a sample of 385 children implanted in a 10-year period. We studied demographic characteristics, hearing, genetics, risk factors and associated malformations (Casselman's and Sennaroglu's classifications). Data were processed using a bivariate descriptive statistical analysis (P<.05). Of all the cases, 58.8% were bilateral (IIa/IIa and I/I were the most common). Of the unilateral cases, IIb was the most frequent. Auditory screening showed a sensitivity of 77.4%. A relationship among bilateral cases and systemic pathology was observed. We found a statistically significant difference when comparing hearing loss impairment and patients with different types of aplasia as defined by Casselman's classification. Computed tomography (CT) scan yielded a sensitivity of 46.3% and a specificity of 85.7%. However, magnetic resonance imaging (MRI) was the most sensitive imaging test. Ten percent of the children in a cochlear implant study had aplasia or hypoplasia of the auditory nerve. The degree of auditory loss was directly related to the different types of aplasia (Casselman's classification) Although CT scan and MRI are complementary, the MRI is the test of choice for detecting auditory nerve malformation. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Evaluation of peripheral auditory pathways and brainstem in obstructive sleep apnea.

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Matsumura, Erika; Matas, Carla Gentile; Magliaro, Fernanda Cristina Leite; Pedreño, Raquel Meirelles; Lorenzi-Filho, Geraldo; Sanches, Seisse Gabriela Gandolfi; Carvallo, Renata Mota Mamede

2016-11-25

Obstructive sleep apnea causes changes in normal sleep architecture, fragmenting it chronically with intermittent hypoxia, leading to serious health consequences in the long term. It is believed that the occurrence of respiratory events during sleep, such as apnea and hypopnea, can impair the transmission of nerve impulses along the auditory pathway that are highly dependent on the supply of oxygen. However, this association is not well established in the literature. To compare the evaluation of peripheral auditory pathway and brainstem among individuals with and without obstructive sleep apnea. The sample consisted of 38 adult males, mean age of 35.8 (±7.2), divided into four groups matched for age and Body Mass Index. The groups were classified based on polysomnography in: control (n=10), mild obstructive sleep apnea (n=11) moderate obstructive sleep apnea (n=8) and severe obstructive sleep apnea (n=9). All study subjects denied a history of risk for hearing loss and underwent audiometry, tympanometry, acoustic reflex and Brainstem Auditory Evoked Response. Statistical analyses were performed using three-factor ANOVA, 2-factor ANOVA, chi-square test, and Fisher's exact test. The significance level for all tests was 5%. There was no difference between the groups for hearing thresholds, tympanometry and evaluated Brainstem Auditory Evoked Response parameters. An association was observed between the presence of obstructive sleep apnea and changes in absolute latency of wave V (p=0.03). There was an association between moderate obstructive sleep apnea and change of the latency of wave V (p=0.01). The presence of obstructive sleep apnea is associated with changes in nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The increase in obstructive sleep apnea severity does not promote worsening of responses assessed by audiometry, tympanometry and Brainstem Auditory Evoked Response. Copyright © 2016 Associação Brasileira de

BDNF Increases Survival and Neuronal Differentiation of Human Neural Precursor Cells Cotransplanted with a Nanofiber Gel to the Auditory Nerve in a Rat Model of Neuronal Damage

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Yu Jiao

2014-01-01

Full Text Available Objectives. To study possible nerve regeneration of a damaged auditory nerve by the use of stem cell transplantation. Methods. We transplanted HNPCs to the rat AN trunk by the internal auditory meatus (IAM. Furthermore, we studied if addition of BDNF affects survival and phenotypic differentiation of the grafted HNPCs. A bioactive nanofiber gel (PA gel, in selected groups mixed with BDNF, was applied close to the implanted cells. Before transplantation, all rats had been deafened by a round window niche application of β-bungarotoxin. This neurotoxin causes a selective toxic destruction of the AN while keeping the hair cells intact. Results. Overall, HNPCs survived well for up to six weeks in all groups. However, transplants receiving the BDNF-containing PA gel demonstrated significantly higher numbers of HNPCs and neuronal differentiation. At six weeks, a majority of the HNPCs had migrated into the brain stem and differentiated. Differentiated human cells as well as neurites were observed in the vicinity of the cochlear nucleus. Conclusion. Our results indicate that human neural precursor cells (HNPC integration with host tissue benefits from additional brain derived neurotrophic factor (BDNF treatment and that these cells appear to be good candidates for further regenerative studies on the auditory nerve (AN.

Intentional preparation of auditory attention-switches: Explicit cueing and sequential switch-predictability.

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Seibold, Julia C; Nolden, Sophie; Oberem, Josefa; Fels, Janina; Koch, Iring

2018-06-01

In an auditory attention-switching paradigm, participants heard two simultaneously spoken number-words, each presented to one ear, and decided whether the target number was smaller or larger than 5 by pressing a left or right key. An instructional cue in each trial indicated which feature had to be used to identify the target number (e.g., female voice). Auditory attention-switch costs were found when this feature changed compared to when it repeated in two consecutive trials. Earlier studies employing this paradigm showed mixed results when they examined whether such cued auditory attention-switches can be prepared actively during the cue-stimulus interval. This study systematically assessed which preconditions are necessary for the advance preparation of auditory attention-switches. Three experiments were conducted that controlled for cue-repetition benefits, modality switches between cue and stimuli, as well as for predictability of the switch-sequence. Only in the third experiment, in which predictability for an attention-switch was maximal due to a pre-instructed switch-sequence and predictable stimulus onsets, active switch-specific preparation was found. These results suggest that the cognitive system can prepare auditory attention-switches, and this preparation seems to be triggered primarily by the memorised switching-sequence and valid expectations about the time of target onset.

Thalamic and parietal brain morphology predicts auditory category learning.

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Scharinger, Mathias; Henry, Molly J; Erb, Julia; Meyer, Lars; Obleser, Jonas

2014-01-01

Auditory categorization is a vital skill involving the attribution of meaning to acoustic events, engaging domain-specific (i.e., auditory) as well as domain-general (e.g., executive) brain networks. A listener's ability to categorize novel acoustic stimuli should therefore depend on both, with the domain-general network being particularly relevant for adaptively changing listening strategies and directing attention to relevant acoustic cues. Here we assessed adaptive listening behavior, using complex acoustic stimuli with an initially salient (but later degraded) spectral cue and a secondary, duration cue that remained nondegraded. We employed voxel-based morphometry (VBM) to identify cortical and subcortical brain structures whose individual neuroanatomy predicted task performance and the ability to optimally switch to making use of temporal cues after spectral degradation. Behavioral listening strategies were assessed by logistic regression and revealed mainly strategy switches in the expected direction, with considerable individual differences. Gray-matter probability in the left inferior parietal lobule (BA 40) and left precentral gyrus was predictive of "optimal" strategy switch, while gray-matter probability in thalamic areas, comprising the medial geniculate body, co-varied with overall performance. Taken together, our findings suggest that successful auditory categorization relies on domain-specific neural circuits in the ascending auditory pathway, while adaptive listening behavior depends more on brain structure in parietal cortex, enabling the (re)direction of attention to salient stimulus properties. © 2013 Published by Elsevier Ltd.

Abnormal Auditory Gain in Hyperacusis: Investigation with a Computational Model

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Peter U. Diehl

2015-07-01

Full Text Available Hyperacusis is a frequent auditory disorder that is characterized by abnormal loudness perception where sounds of relatively normal volume are perceived as too loud or even painfully loud. As Hyperacusis patients show decreased loudness discomfort levels (LDLs and steeper loudness growth functions, it has been hypothesized that hyperacusis might be caused by an increase in neuronal response gain in the auditory system. Moreover, since about 85% of hyperacusis patients also experience tinnitus, the conditions might be caused by a common mechanism. However, the mechanisms that give rise to hyperacusis have remained unclear.Here we have used a computational model of the auditory system to investigate candidate mechanisms for hyperacusis. Assuming that perceived loudness is proportional to the summed activity of all auditory nerve fibers, the model was tuned to reproduce normal loudness perception. We then evaluated a variety of potential hyperacusis gain mechanisms by determining their effects on model equal-loudness contours and comparing the results to the LDLs of hyperacusis patients with normal hearing thresholds. Hyperacusis was best accounted for by an increase in nonlinear gain in the central auditory system. Good fits to the average patient LDLs were obtained for a general increase in gain that affected all frequency channels to the same degree, and also for a frequency-specific gain increase in the high-frequency range. Moreover, the gain needed to be applied after subtraction of spontaneous activity of the auditory nerve, which is in contrast to current theories of tinnitus generation based on amplification of spontaneous activity. Hyperacusis and tinnitus might therefore be caused by different changes in neuronal processing in the central auditory system.

Deviance-Related Responses along the Auditory Hierarchy: Combined FFR, MLR and MMN Evidence

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Shiga, Tetsuya; Althen, Heike; Cornella, Miriam; Zarnowiec, Katarzyna; Yabe, Hirooki; Escera, Carles

2015-01-01

The mismatch negativity (MMN) provides a correlate of automatic auditory discrimination in human auditory cortex that is elicited in response to violation of any acoustic regularity. Recently, deviance-related responses were found at much earlier cortical processing stages as reflected by the middle latency response (MLR) of the auditory evoked potential, and even at the level of the auditory brainstem as reflected by the frequency following response (FFR). However, no study has reported deviance-related responses in the FFR, MLR and long latency response (LLR) concurrently in a single recording protocol. Amplitude-modulated (AM) sounds were presented to healthy human participants in a frequency oddball paradigm to investigate deviance-related responses along the auditory hierarchy in the ranges of FFR, MLR and LLR. AM frequency deviants modulated the FFR, the Na and Nb components of the MLR, and the LLR eliciting the MMN. These findings demonstrate that it is possible to elicit deviance-related responses at three different levels (FFR, MLR and LLR) in one single recording protocol, highlight the involvement of the whole auditory hierarchy in deviance detection and have implications for cognitive and clinical auditory neuroscience. Moreover, the present protocol provides a new research tool into clinical neuroscience so that the functional integrity of the auditory novelty system can now be tested as a whole in a range of clinical populations where the MMN was previously shown to be defective. PMID:26348628

Depth-Dependent Temporal Response Properties in Core Auditory Cortex

OpenAIRE

Christianson, G. Björn; Sahani, Maneesh; Linden, Jennifer F.

2011-01-01

The computational role of cortical layers within auditory cortex has proven difficult to establish. One hypothesis is that interlaminar cortical processing might be dedicated to analyzing temporal properties of sounds; if so, then there should be systematic depth-dependent changes in cortical sensitivity to the temporal context in which a stimulus occurs. We recorded neural responses simultaneously across cortical depth in primary auditory cortex and anterior auditory field of CBA/Ca mice, an...

Auditory evoked potentials: predicting speech therapy outcomes in children with phonological disorders

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Renata Aparecida Leite

2014-03-01

Full Text Available OBJECTIVES: This study investigated whether neurophysiologic responses (auditory evoked potentials differ between typically developed children and children with phonological disorders and whether these responses are modified in children with phonological disorders after speech therapy. METHODS: The participants included 24 typically developing children (Control Group, mean age: eight years and ten months and 23 children clinically diagnosed with phonological disorders (Study Group, mean age: eight years and eleven months. Additionally, 12 study group children were enrolled in speech therapy (Study Group 1, and 11 were not enrolled in speech therapy (Study Group 2. The subjects were submitted to the following procedures: conventional audiological, auditory brainstem response, auditory middle-latency response, and P300 assessments. All participants presented with normal hearing thresholds. The study group 1 subjects were reassessed after 12 speech therapy sessions, and the study group 2 subjects were reassessed 3 months after the initial assessment. Electrophysiological results were compared between the groups. RESULTS: Latency differences were observed between the groups (the control and study groups regarding the auditory brainstem response and the P300 tests. Additionally, the P300 responses improved in the study group 1 children after speech therapy. CONCLUSION: The findings suggest that children with phonological disorders have impaired auditory brainstem and cortical region pathways that may benefit from speech therapy.

Electrophysiological correlates of predictive coding of auditory location in the perception of natural audiovisual events.

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Stekelenburg, Jeroen J; Vroomen, Jean

2012-01-01

In many natural audiovisual events (e.g., a clap of the two hands), the visual signal precedes the sound and thus allows observers to predict when, where, and which sound will occur. Previous studies have reported that there are distinct neural correlates of temporal (when) versus phonetic/semantic (which) content on audiovisual integration. Here we examined the effect of visual prediction of auditory location (where) in audiovisual biological motion stimuli by varying the spatial congruency between the auditory and visual parts. Visual stimuli were presented centrally, whereas auditory stimuli were presented either centrally or at 90° azimuth. Typical sub-additive amplitude reductions (AV - V audiovisual interaction was also found at 40-60 ms (P50) in the spatially congruent condition, while no effect of congruency was found on the suppression of the P2. This indicates that visual prediction of auditory location can be coded very early in auditory processing.

Learning-dependent plasticity in human auditory cortex during appetitive operant conditioning.

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Puschmann, Sebastian; Brechmann, André; Thiel, Christiane M

2013-11-01

Animal experiments provide evidence that learning to associate an auditory stimulus with a reward causes representational changes in auditory cortex. However, most studies did not investigate the temporal formation of learning-dependent plasticity during the task but rather compared auditory cortex receptive fields before and after conditioning. We here present a functional magnetic resonance imaging study on learning-related plasticity in the human auditory cortex during operant appetitive conditioning. Participants had to learn to associate a specific category of frequency-modulated tones with a reward. Only participants who learned this association developed learning-dependent plasticity in left auditory cortex over the course of the experiment. No differential responses to reward predicting and nonreward predicting tones were found in auditory cortex in nonlearners. In addition, learners showed similar learning-induced differential responses to reward-predicting and nonreward-predicting tones in the ventral tegmental area and the nucleus accumbens, two core regions of the dopaminergic neurotransmitter system. This may indicate a dopaminergic influence on the formation of learning-dependent plasticity in auditory cortex, as it has been suggested by previous animal studies. Copyright © 2012 Wiley Periodicals, Inc.

Gender differences in binaural speech-evoked auditory brainstem response: are they clinically significant?

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Jalaei, Bahram; Azmi, Mohd Hafiz Afifi Mohd; Zakaria, Mohd Normani

2018-05-17

Binaurally evoked auditory evoked potentials have good diagnostic values when testing subjects with central auditory deficits. The literature on speech-evoked auditory brainstem response evoked by binaural stimulation is in fact limited. Gender disparities in speech-evoked auditory brainstem response results have been consistently noted but the magnitude of gender difference has not been reported. The present study aimed to compare the magnitude of gender difference in speech-evoked auditory brainstem response results between monaural and binaural stimulations. A total of 34 healthy Asian adults aged 19-30 years participated in this comparative study. Eighteen of them were females (mean age=23.6±2.3 years) and the remaining sixteen were males (mean age=22.0±2.3 years). For each subject, speech-evoked auditory brainstem response was recorded with the synthesized syllable /da/ presented monaurally and binaurally. While latencies were not affected (p>0.05), the binaural stimulation produced statistically higher speech-evoked auditory brainstem response amplitudes than the monaural stimulation (p0.80), substantive gender differences were noted in most of speech-evoked auditory brainstem response peaks for both stimulation modes. The magnitude of gender difference between the two stimulation modes revealed some distinct patterns. Based on these clinically significant results, gender-specific normative data are highly recommended when using speech-evoked auditory brainstem response for clinical and future applications. The preliminary normative data provided in the present study can serve as the reference for future studies on this test among Asian adults. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

The role of the auditory brainstem in processing musically-relevant pitch

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Gavin M. Bidelman

2013-05-01

Full Text Available Neuroimaging work has shed light on the cerebral architecture involved in processing the melodic and harmonic aspects of music. Here, recent evidence is reviewed illustrating that subcortical auditory structures contribute to the early formation and processing of musically-relevant pitch. Electrophysiological recordings from the human brainstem and population responses from the auditory nerve reveal that nascent features of tonal music (e.g., consonance/dissonance, pitch salience, harmonic sonority are evident at early, subcortical levels of the auditory pathway. The salience and harmonicity of brainstem activity is strongly correlated with listeners’ perceptual preferences and perceived consonance for the tonal relationships of music. Moreover, the hierarchical ordering of pitch intervals/chords described by the Western music practice and their perceptual consonance is well-predicted by the salience with which pitch combinations are encoded in subcortical auditory structures. While the neural correlates of consonance can be tuned and exaggerated with musical training, they persist even in the absence of musicianship or long-term enculturation. As such, it is posited that the structural foundations of musical pitch might result from innate processing performed by the central auditory system. A neurobiological predisposition for consonant, pleasant sounding pitch relationships may be one reason why these pitch combinations have been favored by composers and listeners for centuries. It is suggested that important perceptual dimensions of music emerge well before the auditory signal reaches cerebral cortex and prior to attentional engagement. While cortical mechanisms are no doubt critical to the perception, production, and enjoyment of music, the contribution of subcortical structures implicates a more integrated, hierarchically organized network underlying music processing within the brain.

Discrimination of timbre in early auditory responses of the human brain.

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Jaeho Seol

Full Text Available BACKGROUND: The issue of how differences in timbre are represented in the neural response still has not been well addressed, particularly with regard to the relevant brain mechanisms. Here we employ phasing and clipping of tones to produce auditory stimuli differing to describe the multidimensional nature of timbre. We investigated the auditory response and sensory gating as well, using by magnetoencephalography (MEG. METHODOLOGY/PRINCIPAL FINDINGS: Thirty-five healthy subjects without hearing deficit participated in the experiments. Two different or same tones in timbre were presented through conditioning (S1-testing (S2 paradigm as a pair with an interval of 500 ms. As a result, the magnitudes of auditory M50 and M100 responses were different with timbre in both hemispheres. This result might support that timbre, at least by phasing and clipping, is discriminated in the auditory early processing. The second response in a pair affected by S1 in the consecutive stimuli occurred in M100 of the left hemisphere, whereas both M50 and M100 responses to S2 only in the right hemisphere reflected whether two stimuli in a pair were the same or not. Both M50 and M100 magnitudes were different with the presenting order (S1 vs. S2 for both same and different conditions in the both hemispheres. CONCLUSIONS/SIGNIFICANCES: Our results demonstrate that the auditory response depends on timbre characteristics. Moreover, it was revealed that the auditory sensory gating is determined not by the stimulus that directly evokes the response, but rather by whether or not the two stimuli are identical in timbre.

Pathology of the vestibulocochlear nerve

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De Foer, Bert [Department of Radiology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: bert.defoer@GZA.be; Kenis, Christoph [Department of Radiology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: christophkenis@hotmail.com; Van Melkebeke, Deborah [Department of Neurology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: Deborah.vanmelkebeke@Ugent.be; Vercruysse, Jean-Philippe [University Department of ENT, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: jphver@yahoo.com; Somers, Thomas [University Department of ENT, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: Thomas.somers@GZA.be; Pouillon, Marc [Department of Radiology, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: marc.pouillon@GZA.be; Offeciers, Erwin [University Department of ENT, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium)], E-mail: Erwin.offeciers@GZA.be; Casselman, Jan W. [Department of Radiology, AZ Sint-Jan AV Hospital, Ruddershove 10, Bruges (Belgium); Consultant Radiologist, Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Wilrijk (Belgium); Academic Consultent, University of Ghent (Belgium)], E-mail: jan.casselman@azbrugge.be

2010-05-15

There is a large scala of pathology affecting the vestibulocochlear nerve. Magnetic resonance imaging is the method of choice for the investigation of pathology of the vestibulocochlear nerve. Congenital pathology mainly consists of agenesis or hypoplasia of the vestibulocochlear nerve. Tumoral pathology affecting the vestibulocochlear nerve is most frequently located in the internal auditory canal or cerebellopontine angle. Schwannoma of the vestibulocochlear nerve is the most frequently found tumoral lesion followed by meningeoma, arachnoid cyst and epidermoid cyst. The most frequently encountered pathologies as well as some more rare entities are discussed in this chapter.

Pathology of the vestibulocochlear nerve

International Nuclear Information System (INIS)

De Foer, Bert; Kenis, Christoph; Van Melkebeke, Deborah; Vercruysse, Jean-Philippe; Somers, Thomas; Pouillon, Marc; Offeciers, Erwin; Casselman, Jan W.

2010-01-01

There is a large scala of pathology affecting the vestibulocochlear nerve. Magnetic resonance imaging is the method of choice for the investigation of pathology of the vestibulocochlear nerve. Congenital pathology mainly consists of agenesis or hypoplasia of the vestibulocochlear nerve. Tumoral pathology affecting the vestibulocochlear nerve is most frequently located in the internal auditory canal or cerebellopontine angle. Schwannoma of the vestibulocochlear nerve is the most frequently found tumoral lesion followed by meningeoma, arachnoid cyst and epidermoid cyst. The most frequently encountered pathologies as well as some more rare entities are discussed in this chapter.

Bilateral duplication of the internal auditory canal

International Nuclear Information System (INIS)

Weon, Young Cheol; Kim, Jae Hyoung; Choi, Sung Kyu; Koo, Ja-Won

2007-01-01

Duplication of the internal auditory canal is an extremely rare temporal bone anomaly that is believed to result from aplasia or hypoplasia of the vestibulocochlear nerve. We report bilateral duplication of the internal auditory canal in a 28-month-old boy with developmental delay and sensorineural hearing loss. (orig.)

Response properties of neurons in the cat's putamen during auditory discrimination.

Science.gov (United States)

Zhao, Zhenling; Sato, Yu; Qin, Ling

2015-10-01

The striatum integrates diverse convergent input and plays a critical role in the goal-directed behaviors. To date, the auditory functions of striatum are less studied. Recently, it was demonstrated that auditory cortico-striatal projections influence behavioral performance during a frequency discrimination task. To reveal the functions of striatal neurons in auditory discrimination, we recorded the single-unit spike activities in the putamen (dorsal striatum) of free-moving cats while performing a Go/No-go task to discriminate the sounds with different modulation rates (12.5 Hz vs. 50 Hz) or envelopes (damped vs. ramped). We found that the putamen neurons can be broadly divided into four groups according to their contributions to sound discrimination. First, 40% of neurons showed vigorous responses synchronized to the sound envelope, and could precisely discriminate different sounds. Second, 18% of neurons showed a high preference of ramped to damped sounds, but no preference for modulation rate. They could only discriminate the change of sound envelope. Third, 27% of neurons rapidly adapted to the sound stimuli, had no ability of sound discrimination. Fourth, 15% of neurons discriminated the sounds dependent on the reward-prediction. Comparing to passively listening condition, the activities of putamen neurons were significantly enhanced by the engagement of the auditory tasks, but not modulated by the cat's behavioral choice. The coexistence of multiple types of neurons suggests that the putamen is involved in the transformation from auditory representation to stimulus-reward association. Copyright © 2015 Elsevier B.V. All rights reserved.

Auditory-visual integration modulates location-specific repetition suppression of auditory responses.

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Shrem, Talia; Murray, Micah M; Deouell, Leon Y

2017-11-01

Space is a dimension shared by different modalities, but at what stage spatial encoding is affected by multisensory processes is unclear. Early studies observed attenuation of N1/P2 auditory evoked responses following repetition of sounds from the same location. Here, we asked whether this effect is modulated by audiovisual interactions. In two experiments, using a repetition-suppression paradigm, we presented pairs of tones in free field, where the test stimulus was a tone presented at a fixed lateral location. Experiment 1 established a neural index of auditory spatial sensitivity, by comparing the degree of attenuation of the response to test stimuli when they were preceded by an adapter sound at the same location versus 30° or 60° away. We found that the degree of attenuation at the P2 latency was inversely related to the spatial distance between the test stimulus and the adapter stimulus. In Experiment 2, the adapter stimulus was a tone presented from the same location or a more medial location than the test stimulus. The adapter stimulus was accompanied by a simultaneous flash displayed orthogonally from one of the two locations. Sound-flash incongruence reduced accuracy in a same-different location discrimination task (i.e., the ventriloquism effect) and reduced the location-specific repetition-suppression at the P2 latency. Importantly, this multisensory effect included topographic modulations, indicative of changes in the relative contribution of underlying sources across conditions. Our findings suggest that the auditory response at the P2 latency is affected by spatially selective brain activity, which is affected crossmodally by visual information. © 2017 Society for Psychophysiological Research.

Electrophysiological correlates of predictive coding of auditory location in the perception of natural audiovisual events

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Jeroen eStekelenburg

2012-05-01

Full Text Available In many natural audiovisual events (e.g., a clap of the two hands, the visual signal precedes the sound and thus allows observers to predict when, where, and which sound will occur. Previous studies have already reported that there are distinct neural correlates of temporal (when versus phonetic/semantic (which content on audiovisual integration. Here we examined the effect of visual prediction of auditory location (where in audiovisual biological motion stimuli by varying the spatial congruency between the auditory and visual part of the audiovisual stimulus. Visual stimuli were presented centrally, whereas auditory stimuli were presented either centrally or at 90° azimuth. Typical subadditive amplitude reductions (AV – V < A were found for the auditory N1 and P2 for spatially congruent and incongruent conditions. The new finding is that the N1 suppression was larger for spatially congruent stimuli. A very early audiovisual interaction was also found at 30-50 ms in the spatially congruent condition, while no effect of congruency was found on the suppression of the P2. This indicates that visual prediction of auditory location can be coded very early in auditory processing.

Adult plasticity in the subcortical auditory pathway of the maternal mouse.

Directory of Open Access Journals (Sweden)

Jason A Miranda

Full Text Available Subcortical auditory nuclei were traditionally viewed as non-plastic in adulthood so that acoustic information could be stably conveyed to higher auditory areas. Studies in a variety of species, including humans, now suggest that prolonged acoustic training can drive long-lasting brainstem plasticity. The neurobiological mechanisms for such changes are not well understood in natural behavioral contexts due to a relative dearth of in vivo animal models in which to study this. Here, we demonstrate in a mouse model that a natural life experience with increased demands on the auditory system - motherhood - is associated with improved temporal processing in the subcortical auditory pathway. We measured the auditory brainstem response to test whether mothers and pup-naïve virgin mice differed in temporal responses to both broadband and tone stimuli, including ultrasonic frequencies found in mouse pup vocalizations. Mothers had shorter latencies for early ABR peaks, indicating plasticity in the auditory nerve and the cochlear nucleus. Shorter interpeak latency between waves IV and V also suggest plasticity in the inferior colliculus. Hormone manipulations revealed that these cannot be explained solely by estrogen levels experienced during pregnancy and parturition in mothers. In contrast, we found that pup-care experience, independent of pregnancy and parturition, contributes to shortening auditory brainstem response latencies. These results suggest that acoustic experience in the maternal context imparts plasticity on early auditory processing that lasts beyond pup weaning. In addition to establishing an animal model for exploring adult auditory brainstem plasticity in a neuroethological context, our results have broader implications for models of perceptual, behavioral and neural changes that arise during maternity, where subcortical sensorineural plasticity has not previously been considered.

Adult plasticity in the subcortical auditory pathway of the maternal mouse.

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Miranda, Jason A; Shepard, Kathryn N; McClintock, Shannon K; Liu, Robert C

2014-01-01

Subcortical auditory nuclei were traditionally viewed as non-plastic in adulthood so that acoustic information could be stably conveyed to higher auditory areas. Studies in a variety of species, including humans, now suggest that prolonged acoustic training can drive long-lasting brainstem plasticity. The neurobiological mechanisms for such changes are not well understood in natural behavioral contexts due to a relative dearth of in vivo animal models in which to study this. Here, we demonstrate in a mouse model that a natural life experience with increased demands on the auditory system - motherhood - is associated with improved temporal processing in the subcortical auditory pathway. We measured the auditory brainstem response to test whether mothers and pup-naïve virgin mice differed in temporal responses to both broadband and tone stimuli, including ultrasonic frequencies found in mouse pup vocalizations. Mothers had shorter latencies for early ABR peaks, indicating plasticity in the auditory nerve and the cochlear nucleus. Shorter interpeak latency between waves IV and V also suggest plasticity in the inferior colliculus. Hormone manipulations revealed that these cannot be explained solely by estrogen levels experienced during pregnancy and parturition in mothers. In contrast, we found that pup-care experience, independent of pregnancy and parturition, contributes to shortening auditory brainstem response latencies. These results suggest that acoustic experience in the maternal context imparts plasticity on early auditory processing that lasts beyond pup weaning. In addition to establishing an animal model for exploring adult auditory brainstem plasticity in a neuroethological context, our results have broader implications for models of perceptual, behavioral and neural changes that arise during maternity, where subcortical sensorineural plasticity has not previously been considered.

Modeling of Auditory Neuron Response Thresholds with Cochlear Implants

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Frederic Venail

2015-01-01

Full Text Available The quality of the prosthetic-neural interface is a critical point for cochlear implant efficiency. It depends not only on technical and anatomical factors such as electrode position into the cochlea (depth and scalar placement, electrode impedance, and distance between the electrode and the stimulated auditory neurons, but also on the number of functional auditory neurons. The efficiency of electrical stimulation can be assessed by the measurement of e-CAP in cochlear implant users. In the present study, we modeled the activation of auditory neurons in cochlear implant recipients (nucleus device. The electrical response, measured using auto-NRT (neural responses telemetry algorithm, has been analyzed using multivariate regression with cubic splines in order to take into account the variations of insertion depth of electrodes amongst subjects as well as the other technical and anatomical factors listed above. NRT thresholds depend on the electrode squared impedance (β = −0.11 ± 0.02, P<0.01, the scalar placement of the electrodes (β = −8.50 ± 1.97, P<0.01, and the depth of insertion calculated as the characteristic frequency of auditory neurons (CNF. Distribution of NRT residues according to CNF could provide a proxy of auditory neurons functioning in implanted cochleas.

Evaluation of the Auditory Pathway in Traffic Policemen

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Vipul Indora

2017-04-01

Full Text Available Background: Traffic policemen working at heavy traffic junctions are continuously exposed to high level of noise and its health consequences. Objective: To assess the hearing pathway in traffic policemen by means of brainstem evoked response audiometry (BERA, mid-latency response (MLR, and slow vertex response (SVR. Methods: In this observational comparative study, BERA, MLR, and SVR were tested in 35 male traffic policemen with field posting of more than 3 years. 35 age-matched men working in our college served as controls. Results: Increase in the latencies of waves I and III of BERA, and IPL I-III were observed. Compared to controls, the MLR and SVR waves showed no significant changes in studied policemen. Conclusion: We found that chronic exposure of traffic policemen to noise resulted in delayed conduction in peripheral part of the auditory pathway, ie, auditory nerve up to the level of superior olivary nucleus; no impairment was observed at the level of sub-cortical, cortical, or the association areas.

Narrow, duplicated internal auditory canal

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Ferreira, T. [Servico de Neurorradiologia, Hospital Garcia de Orta, Avenida Torrado da Silva, 2801-951, Almada (Portugal); Shayestehfar, B. [Department of Radiology, UCLA Oliveview School of Medicine, Los Angeles, California (United States); Lufkin, R. [Department of Radiology, UCLA School of Medicine, Los Angeles, California (United States)

2003-05-01

A narrow internal auditory canal (IAC) constitutes a relative contraindication to cochlear implantation because it is associated with aplasia or hypoplasia of the vestibulocochlear nerve or its cochlear branch. We report an unusual case of a narrow, duplicated IAC, divided by a bony septum into a superior relatively large portion and an inferior stenotic portion, in which we could identify only the facial nerve. This case adds support to the association between a narrow IAC and aplasia or hypoplasia of the vestibulocochlear nerve. The normal facial nerve argues against the hypothesis that the narrow IAC is the result of a primary bony defect which inhibits the growth of the vestibulocochlear nerve. (orig.)

Microsurgical Decompression of the Cochlear Nerve to Treat Disabling Tinnitus via an Endoscope-Assisted Retrosigmoid Approach: The Padua Experience.

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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.

Modeling the response of small myelinated axons in a compound nerve to kilohertz frequency signals.

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Pelot, N A; Behrend, C E; Grill, W M

2017-08-01

There is growing interest in electrical neuromodulation of peripheral nerves, particularly autonomic nerves, to treat various diseases. Electrical signals in the kilohertz frequency (KHF) range can produce different responses, including conduction block. For example, EnteroMedics' vBloc ® therapy for obesity delivers 5 kHz stimulation to block the abdominal vagus nerves, but the mechanisms of action are unclear. We developed a two-part computational model, coupling a 3D finite element model of a cuff electrode around the human abdominal vagus nerve with biophysically-realistic electrical circuit equivalent (cable) model axons (1, 2, and 5.7 µm in diameter). We developed an automated algorithm to classify conduction responses as subthreshold (transmission), KHF-evoked activity (excitation), or block. We quantified neural responses across kilohertz frequencies (5-20 kHz), amplitudes (1-8 mA), and electrode designs. We found heterogeneous conduction responses across the modeled nerve trunk, both for a given parameter set and across parameter sets, although most suprathreshold responses were excitation, rather than block. The firing patterns were irregular near transmission and block boundaries, but otherwise regular, and mean firing rates varied with electrode-fibre distance. Further, we identified excitation responses at amplitudes above block threshold, termed 're-excitation', arising from action potentials initiated at virtual cathodes. Excitation and block thresholds decreased with smaller electrode-fibre distances, larger fibre diameters, and lower kilohertz frequencies. A point source model predicted a larger fraction of blocked fibres and greater change of threshold with distance as compared to the realistic cuff and nerve model. Our findings of widespread asynchronous KHF-evoked activity suggest that conduction block in the abdominal vagus nerves is unlikely with current clinical parameters. Our results indicate that compound neural or downstream muscle

Perception of stochastically undersampled sound waveforms: A model of auditory deafferentation

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Enrique A Lopez-Poveda

2013-07-01

Full Text Available Auditory deafferentation, or permanent loss of auditory nerve afferent terminals, occurs after noise overexposure and aging and may accompany many forms of hearing loss. It could cause significant auditory impairment but is undetected by regular clinical tests and so its effects on perception are poorly understood. Here, we hypothesize and test a neural mechanism by which deafferentation could deteriorate perception. The basic idea is that the spike train produced by each auditory afferent resembles a stochastically digitized version of the sound waveform and that the quality of the waveform representation in the whole nerve depends on the number of aggregated spike trains or auditory afferents. We reason that because spikes occur stochastically in time with a higher probability for high- than for low-intensity sounds, more afferents would be required for the nerve to faithfully encode high-frequency or low-intensity waveform features than low-frequency or high-intensity features. Deafferentation would thus degrade the encoding of these features. We further reason that due to the stochastic nature of nerve firing, the degradation would be greater in noise than in quiet. This hypothesis is tested using a vocoder. Sounds were filtered through ten adjacent frequency bands. For the signal in each band, multiple stochastically subsampled copies were obtained to roughly mimic different stochastic representations of that signal conveyed by different auditory afferents innervating a given cochlear region. These copies were then aggregated to obtain an acoustic stimulus. Tone detection and speech identification tests were performed by young, normal-hearing listeners using different numbers of stochastic samplers per frequency band in the vocoder. Results support the hypothesis that stochastic undersampling of the sound waveform, inspired by deafferentation, impairs speech perception in noise more than in quiet, consistent with auditory aging effects.

Perception of stochastically undersampled sound waveforms: a model of auditory deafferentation

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Lopez-Poveda, Enrique A.; Barrios, Pablo

2013-01-01

Auditory deafferentation, or permanent loss of auditory nerve afferent terminals, occurs after noise overexposure and aging and may accompany many forms of hearing loss. It could cause significant auditory impairment but is undetected by regular clinical tests and so its effects on perception are poorly understood. Here, we hypothesize and test a neural mechanism by which deafferentation could deteriorate perception. The basic idea is that the spike train produced by each auditory afferent resembles a stochastically digitized version of the sound waveform and that the quality of the waveform representation in the whole nerve depends on the number of aggregated spike trains or auditory afferents. We reason that because spikes occur stochastically in time with a higher probability for high- than for low-intensity sounds, more afferents would be required for the nerve to faithfully encode high-frequency or low-intensity waveform features than low-frequency or high-intensity features. Deafferentation would thus degrade the encoding of these features. We further reason that due to the stochastic nature of nerve firing, the degradation would be greater in noise than in quiet. This hypothesis is tested using a vocoder. Sounds were filtered through ten adjacent frequency bands. For the signal in each band, multiple stochastically subsampled copies were obtained to roughly mimic different stochastic representations of that signal conveyed by different auditory afferents innervating a given cochlear region. These copies were then aggregated to obtain an acoustic stimulus. Tone detection and speech identification tests were performed by young, normal-hearing listeners using different numbers of stochastic samplers per frequency band in the vocoder. Results support the hypothesis that stochastic undersampling of the sound waveform, inspired by deafferentation, impairs speech perception in noise more than in quiet, consistent with auditory aging effects. PMID:23882176

Auditory and visual sustained attention in Down syndrome.

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Faught, Gayle G; Conners, Frances A; Himmelberger, Zachary M

2016-01-01

Sustained attention (SA) is important to task performance and development of higher functions. It emerges as a separable component of attention during preschool and shows incremental improvements during this stage of development. The current study investigated if auditory and visual SA match developmental level or are particular challenges for youth with DS. Further, we sought to determine if there were modality effects in SA that could predict those seen in short-term memory (STM). We compared youth with DS to typically developing youth matched for nonverbal mental age and receptive vocabulary. Groups completed auditory and visual sustained attention to response tests (SARTs) and STM tasks. Results indicated groups performed similarly on both SARTs, even over varying cognitive ability. Further, within groups participants performed similarly on auditory and visual SARTs, thus SA could not predict modality effects in STM. However, SA did generally predict a significant portion of unique variance in groups' STM. Ultimately, results suggested both auditory and visual SA match developmental level in DS. Further, SA generally predicts STM, though SA does not necessarily predict the pattern of poor auditory relative to visual STM characteristic of DS. Copyright © 2016 Elsevier Ltd. All rights reserved.

The absence of later wave components in auditory brainstem responses as an initial manifestation of type 2 Gaucher disease.

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Okubo, Yusuke; Goto, Masahiro; Sakakibara, Hiroshi; Terakawa, Toshiro; Kaneko, Takashi; Miyama, Sahoko

2014-12-01

Type 2 Gaucher disease is the most severe neuronopathic form of Gaucher disease and is characterized by severe neurodegeneration with brainstem involvement and organ failure. Prediction or diagnosis of type 2 Gaucher disease before the development of neurological complications is difficult. A 5-month-old female infant presented with deafness without other neurological abnormalities. Auditory brainstem response analysis revealed the absence of later wave components. Two months later, muscular rigidity became evident, followed by the development of opisthotonus and strabismus. Rapid progression of splenomegaly led to the diagnosis of type 2 Gaucher disease. Abnormal auditory brainstem response findings may already exist before the development of severe brainstem abnormalities such as muscular rigidity and opisthotonus in type 2 Gaucher disease. When patients present with deafness and absent later wave components on auditory brainstem response, type 2 Gaucher disease should be included in the differential diagnosis even in the absence of other neurological abnormalities. Copyright © 2014 Elsevier Inc. All rights reserved.

Middle components of the auditory evoked response in bilateral temporal lobe lesions. Report on a patient with auditory agnosia

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Parving, A; Salomon, G; Elberling, Claus

1980-01-01

An investigation of the middle components of the auditory evoked response (10--50 msec post-stimulus) in a patient with auditory agnosia is reported. Bilateral temporal lobe infarctions were proved by means of brain scintigraphy, CAT scanning, and regional cerebral blood flow measurements...

Transitional Probabilities Are Prioritized over Stimulus/Pattern Probabilities in Auditory Deviance Detection: Memory Basis for Predictive Sound Processing.

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Mittag, Maria; Takegata, Rika; Winkler, István

2016-09-14

Representations encoding the probabilities of auditory events do not directly support predictive processing. In contrast, information about the probability with which a given sound follows another (transitional probability) allows predictions of upcoming sounds. We tested whether behavioral and cortical auditory deviance detection (the latter indexed by the mismatch negativity event-related potential) relies on probabilities of sound patterns or on transitional probabilities. We presented healthy adult volunteers with three types of rare tone-triplets among frequent standard triplets of high-low-high (H-L-H) or L-H-L pitch structure: proximity deviant (H-H-H/L-L-L), reversal deviant (L-H-L/H-L-H), and first-tone deviant (L-L-H/H-H-L). If deviance detection was based on pattern probability, reversal and first-tone deviants should be detected with similar latency because both differ from the standard at the first pattern position. If deviance detection was based on transitional probabilities, then reversal deviants should be the most difficult to detect because, unlike the other two deviants, they contain no low-probability pitch transitions. The data clearly showed that both behavioral and cortical auditory deviance detection uses transitional probabilities. Thus, the memory traces underlying cortical deviance detection may provide a link between stimulus probability-based change/novelty detectors operating at lower levels of the auditory system and higher auditory cognitive functions that involve predictive processing. Our research presents the first definite evidence for the auditory system prioritizing transitional probabilities over probabilities of individual sensory events. Forming representations for transitional probabilities paves the way for predictions of upcoming sounds. Several recent theories suggest that predictive processing provides the general basis of human perception, including important auditory functions, such as auditory scene analysis. Our

Developmental trends in auditory processing can provide early predictions of language acquisition in young infants.

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Chonchaiya, Weerasak; Tardif, Twila; Mai, Xiaoqin; Xu, Lin; Li, Mingyan; Kaciroti, Niko; Kileny, Paul R; Shao, Jie; Lozoff, Betsy

2013-03-01

Auditory processing capabilities at the subcortical level have been hypothesized to impact an individual's development of both language and reading abilities. The present study examined whether auditory processing capabilities relate to language development in healthy 9-month-old infants. Participants were 71 infants (31 boys and 40 girls) with both Auditory Brainstem Response (ABR) and language assessments. At 6 weeks and/or 9 months of age, the infants underwent ABR testing using both a standard hearing screening protocol with 30 dB clicks and a second protocol using click pairs separated by 8, 16, and 64-ms intervals presented at 80 dB. We evaluated the effects of interval duration on ABR latency and amplitude elicited by the second click. At 9 months, language development was assessed via parent report on the Chinese Communicative Development Inventory - Putonghua version (CCDI-P). Wave V latency z-scores of the 64-ms condition at 6 weeks showed strong direct relationships with Wave V latency in the same condition at 9 months. More importantly, shorter Wave V latencies at 9 months showed strong relationships with the CCDI-P composite consisting of phrases understood, gestures, and words produced. Likewise, infants who had greater decreases in Wave V latencies from 6 weeks to 9 months had higher CCDI-P composite scores. Females had higher language development scores and shorter Wave V latencies at both ages than males. Interestingly, when the ABR Wave V latencies at both ages were taken into account, the direct effects of gender on language disappeared. In conclusion, these results support the importance of low-level auditory processing capabilities for early language acquisition in a population of typically developing young infants. Moreover, the auditory brainstem response in this paradigm shows promise as an electrophysiological marker to predict individual differences in language development in young children. © 2012 Blackwell Publishing Ltd.

Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

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Renata Mota Mamede de Carvallo

2008-09-01

Full Text Available Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU, as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests could be applied to all babies. The “pass” result for the group of babies from the nursery was 94.7% using Transient Evoked Otoacoustic Emissions and 96% using Automatic Auditory Brainstem Response. The newborn intensive care unit group obtained 87.1% on Transient Evoked Otoacoustic Emissions and 80% on the Automatic Auditory Brainstem Response, and there was no statistical difference between the procedures when the groups were evaluated individually. However, comparing the groups, Transient Evoked Otoacoustic Emissions were presented in 94.7% of the nursery babies and in 87.1% in the group from the newborn intensive care unit. Considering the Automatic Auditory Brainstem Response, we found 96 and 87%, respectively. Cconclusions: Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response had similar “pass” and “fail” results when the procedures were applied to neonates from the regular nursery, and the combined tests were more precise to detect hearing impairment in the newborn intensive care unit babies.

Predicting hearing thresholds in occupational noise-induced hearing loss by auditory steady state responses.

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Attias, Joseph; Karawani, Hanin; Shemesh, Rafi; Nageris, Ben

2014-01-01

Currently available behavioral tools for the assessment of noise-induced hearing loss (NIHL) depend on the reliable cooperation of the subject. Furthermore, in workers' compensation cases, there is considerable financial gain to be had from exaggerating symptoms, such that accurate assessment of true hearing threshold levels is essential. An alternative objective physiologic tool for assessing NIHL is the auditory steady state response (ASSR) test, which combines frequency specificity with a high level of auditory stimulation, making it applicable for the evaluation of subjects with a moderate to severe deficit. The primary aim of the study was to assess the value of the multifrequency ASSR test in predicting the behavioral warble-tone audiogram in a large sample of young subjects with NIHL of varying severity or with normal hearing. The secondary goal was to assess suprathreshold ASSR growth functions in these two groups. The study group included 157 subjects regularly exposed to high levels of occupational noise, who attended a university-associated audiological clinic for evaluation of NIHL from 2009 through 2011. All underwent a behavioral audiogram, and on the basis of the findings, were divided into those with NIHL (108 subjects, 216 ears) or normal hearing (49 subjects, 98 ears). The accuracy of the ASSR threshold estimations for frequencies of 500, 1000, 2000, and 4000 Hz was compared between groups, and the specificity and sensitivity of the ASSR test in differentiating ears with or without NIHL was calculated using receiver operating characteristic analysis. Linear regression analysis was used to formulate an equation to predict the behavioral warble-tone audiogram at each test frequency using ASSR thresholds. Multifrequency ASSR amplitude growth as a function of stimulus intensity was compared between the NIHL and normal-hearing groups for 1000 Hz and 4000 Hz carrier frequencies. In the subjects with NIHL, ASSR thresholds to various frequencies were

Basic response characteristics of auditory nerve fibers in the grassfrog (Rana temporaria)

DEFF Research Database (Denmark)

Christensen-Dalsgaard, J; Jørgensen, M B; Kanneworff, M

1998-01-01

-excitatory suppression (PS) of their spontaneous activity. The duration of PS increased with sound level, also in fibers showing a decrease in firing rate at high intensities. Most fibers showing one-tone suppression did not show PS at their best suppression frequencies. Strong suppression was observed also in very......Responses to free-field sound of 401 fibers from the VIIIth nerve of the grassfrog, Rana temporaria, are described. The spontaneous activities of the fibers ranged from 0 to 75 spikes/s, showing only weak correlation with frequency or sensitivity of the fibers. The highest spontaneous activities...... were approximately twice as high as reported previously for frogs. Best frequencies ranged from 100 to 1600 Hz and thresholds ranged from 21 to 80 dB SPL. The median dynamic range was 20 dB and the slopes of the rate-level curves ranged from 5 to 20 spikes/(s-dB). Most of the units showed post...

Direct recordings from the auditory cortex in a cochlear implant user.

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Nourski, Kirill V; Etler, Christine P; Brugge, John F; Oya, Hiroyuki; Kawasaki, Hiroto; Reale, Richard A; Abbas, Paul J; Brown, Carolyn J; Howard, Matthew A

2013-06-01

Electrical stimulation of the auditory nerve with a cochlear implant (CI) is the method of choice for treatment of severe-to-profound hearing loss. Understanding how the human auditory cortex responds to CI stimulation is important for advances in stimulation paradigms and rehabilitation strategies. In this study, auditory cortical responses to CI stimulation were recorded intracranially in a neurosurgical patient to examine directly the functional organization of the auditory cortex and compare the findings with those obtained in normal-hearing subjects. The subject was a bilateral CI user with a 20-year history of deafness and refractory epilepsy. As part of the epilepsy treatment, a subdural grid electrode was implanted over the left temporal lobe. Pure tones, click trains, sinusoidal amplitude-modulated noise, and speech were presented via the auxiliary input of the right CI speech processor. Additional experiments were conducted with bilateral CI stimulation. Auditory event-related changes in cortical activity, characterized by the averaged evoked potential and event-related band power, were localized to posterolateral superior temporal gyrus. Responses were stable across recording sessions and were abolished under general anesthesia. Response latency decreased and magnitude increased with increasing stimulus level. More apical intracochlear stimulation yielded the largest responses. Cortical evoked potentials were phase-locked to the temporal modulations of periodic stimuli and speech utterances. Bilateral electrical stimulation resulted in minimal artifact contamination. This study demonstrates the feasibility of intracranial electrophysiological recordings of responses to CI stimulation in a human subject, shows that cortical response properties may be similar to those obtained in normal-hearing individuals, and provides a basis for future comparisons with extracranial recordings.

Anatomy, Physiology and Function of the Auditory System

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Kollmeier, Birger

The human ear consists of the outer ear (pinna or concha, outer ear canal, tympanic membrane), the middle ear (middle ear cavity with the three ossicles malleus, incus and stapes) and the inner ear (cochlea which is connected to the three semicircular canals by the vestibule, which provides the sense of balance). The cochlea is connected to the brain stem via the eighth brain nerve, i.e. the vestibular cochlear nerve or nervus statoacusticus. Subsequently, the acoustical information is processed by the brain at various levels of the auditory system. An overview about the anatomy of the auditory system is provided by Figure 1.

Auditory Neural Prostheses – A Window to the Future

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Mohan Kameshwaran

2015-06-01

Full Text Available Hearing loss is one of the commonest congenital anomalies to affect children world-over. The incidence of congenital hearing loss is more pronounced in developing countries like the Indian sub-continent, especially with the problems of consanguinity. Hearing loss is a double tragedy, as it leads to not only deafness but also language deprivation. However, hearing loss is the only truly remediable handicap, due to remarkable advances in biomedical engineering and surgical techniques. Auditory neural prostheses help to augment or restore hearing by integration of an external circuitry with the peripheral hearing apparatus and the central circuitry of the brain. A cochlear implant (CI is a surgically implantable device that helps restore hearing in patients with severe-profound hearing loss, unresponsive to amplification by conventional hearing aids. CIs are electronic devices designed to detect mechanical sound energy and convert it into electrical signals that can be delivered to the coch­lear nerve, bypassing the damaged hair cells of the coch­lea. The only true prerequisite is an intact auditory nerve. The emphasis is on implantation as early as possible to maximize speech understanding and perception. Bilateral CI has significant benefits which include improved speech perception in noisy environments and improved sound localization. Presently, the indications for CI have widened and these expanded indications for implantation are related to age, additional handicaps, residual hearing, and special etiologies of deafness. Combined electric and acoustic stimulation (EAS / hybrid device is designed for individuals with binaural low-frequency hearing and severe-to-profound high-frequency hearing loss. Auditory brainstem implantation (ABI is a safe and effective means of hearing rehabilitation in patients with retrocochlear disorders, such as neurofibromatosis type 2 (NF2 or congenital cochlear nerve aplasia, wherein the cochlear nerve is damaged

Modeling the response of small myelinated axons in a compound nerve to kilohertz frequency signals

Science.gov (United States)

Pelot, N. A.; Behrend, C. E.; Grill, W. M.

2017-08-01

Objective. There is growing interest in electrical neuromodulation of peripheral nerves, particularly autonomic nerves, to treat various diseases. Electrical signals in the kilohertz frequency (KHF) range can produce different responses, including conduction block. For example, EnteroMedics’ vBloc® therapy for obesity delivers 5 kHz stimulation to block the abdominal vagus nerves, but the mechanisms of action are unclear. Approach. We developed a two-part computational model, coupling a 3D finite element model of a cuff electrode around the human abdominal vagus nerve with biophysically-realistic electrical circuit equivalent (cable) model axons (1, 2, and 5.7 µm in diameter). We developed an automated algorithm to classify conduction responses as subthreshold (transmission), KHF-evoked activity (excitation), or block. We quantified neural responses across kilohertz frequencies (5-20 kHz), amplitudes (1-8 mA), and electrode designs. Main results. We found heterogeneous conduction responses across the modeled nerve trunk, both for a given parameter set and across parameter sets, although most suprathreshold responses were excitation, rather than block. The firing patterns were irregular near transmission and block boundaries, but otherwise regular, and mean firing rates varied with electrode-fibre distance. Further, we identified excitation responses at amplitudes above block threshold, termed ‘re-excitation’, arising from action potentials initiated at virtual cathodes. Excitation and block thresholds decreased with smaller electrode-fibre distances, larger fibre diameters, and lower kilohertz frequencies. A point source model predicted a larger fraction of blocked fibres and greater change of threshold with distance as compared to the realistic cuff and nerve model. Significance. Our findings of widespread asynchronous KHF-evoked activity suggest that conduction block in the abdominal vagus nerves is unlikely with current clinical parameters. Our

Rapid measurement of auditory filter shape in mice using the auditory brainstem response and notched noise.

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Lina, Ioan A; Lauer, Amanda M

2013-04-01

The notched noise method is an effective procedure for measuring frequency resolution and auditory filter shapes in both human and animal models of hearing. Briefly, auditory filter shape and bandwidth estimates are derived from masked thresholds for tones presented in noise containing widening spectral notches. As the spectral notch widens, increasingly less of the noise falls within the auditory filter and the tone becomes more detectible until the notch width exceeds the filter bandwidth. Behavioral procedures have been used for the derivation of notched noise auditory filter shapes in mice; however, the time and effort needed to train and test animals on these tasks renders a constraint on the widespread application of this testing method. As an alternative procedure, we combined relatively non-invasive auditory brainstem response (ABR) measurements and the notched noise method to estimate auditory filters in normal-hearing mice at center frequencies of 8, 11.2, and 16 kHz. A complete set of simultaneous masked thresholds for a particular tone frequency were obtained in about an hour. ABR-derived filter bandwidths broadened with increasing frequency, consistent with previous studies. The ABR notched noise procedure provides a fast alternative to estimating frequency selectivity in mice that is well-suited to high through-put or time-sensitive screening. Copyright © 2013 Elsevier B.V. All rights reserved.

Dose-dependent suppression by ethanol of transient auditory 40-Hz response.

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Jääskeläinen, I P; Hirvonen, J; Saher, M; Pekkonen, E; Sillanaukee, P; Näätänen, R; Tiitinen, H

2000-02-01

Acute alcohol (ethanol) challenge is known to induce various cognitive disturbances, yet the neural basis of the effect is poorly known. The auditory transient evoked gamma-band (40-Hz) oscillatory responses have been suggested to be associated with various perceptual and cognitive functions in humans; however, alcohol effects on auditory 40-Hz responses have not been investigated to date. The objective of the study was to test the dose-related impact of alcohol on auditory transient evoked 40-Hz responses during a selective-attention task. Ten healthy social drinkers ingested, in four separate sessions, 0.00, 0. 25, 0.50, or 0.75 g/kg of 10% (v/v) alcohol solution. The order of the sessions was randomized and a double-blind procedure was employed. During a selective attention task, 300-Hz standard and 330-Hz deviant tones were presented to the left ear, and 1000-Hz standards and 1100-Hz deviants to the right ear of the subjects (P=0. 425 for each standard, P=0.075 for each deviant). The subjects attended to a designated ear, and were to detect the deviants therein while ignoring tones to the other ear. The auditory transient evoked 40-Hz responses elicited by both the attended and unattended standard tones were significantly suppressed by the 0.50 and 0.75 g/kg alcohol doses. Alcohol suppresses auditory transient evoked 40-Hz oscillations already with moderate blood alcohol concentrations. Given the putative role of gamma-band oscillations in cognition, this finding could be associated with certain alcohol-induced cognitive deficits.

Auditory-neurophysiological responses to speech during early childhood: Effects of background noise.

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White-Schwoch, Travis; Davies, Evan C; Thompson, Elaine C; Woodruff Carr, Kali; Nicol, Trent; Bradlow, Ann R; Kraus, Nina

2015-10-01

Early childhood is a critical period of auditory learning, during which children are constantly mapping sounds to meaning. But this auditory learning rarely occurs in ideal listening conditions-children are forced to listen against a relentless din. This background noise degrades the neural coding of these critical sounds, in turn interfering with auditory learning. Despite the importance of robust and reliable auditory processing during early childhood, little is known about the neurophysiology underlying speech processing in children so young. To better understand the physiological constraints these adverse listening scenarios impose on speech sound coding during early childhood, auditory-neurophysiological responses were elicited to a consonant-vowel syllable in quiet and background noise in a cohort of typically-developing preschoolers (ages 3-5 yr). Overall, responses were degraded in noise: they were smaller, less stable across trials, slower, and there was poorer coding of spectral content and the temporal envelope. These effects were exacerbated in response to the consonant transition relative to the vowel, suggesting that the neural coding of spectrotemporally-dynamic speech features is more tenuous in noise than the coding of static features-even in children this young. Neural coding of speech temporal fine structure, however, was more resilient to the addition of background noise than coding of temporal envelope information. Taken together, these results demonstrate that noise places a neurophysiological constraint on speech processing during early childhood by causing a breakdown in neural processing of speech acoustics. These results may explain why some listeners have inordinate difficulties understanding speech in noise. Speech-elicited auditory-neurophysiological responses offer objective insight into listening skills during early childhood by reflecting the integrity of neural coding in quiet and noise; this paper documents typical response

Altered auditory BOLD response to conspecific birdsong in zebra finches with stuttered syllables.

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Henning U Voss

2010-12-01

Full Text Available How well a songbird learns a song appears to depend on the formation of a robust auditory template of its tutor's song. Using functional magnetic resonance neuroimaging we examine auditory responses in two groups of zebra finches that differ in the type of song they sing after being tutored by birds producing stuttering-like syllable repetitions in their songs. We find that birds that learn to produce the stuttered syntax show attenuated blood oxygenation level-dependent (BOLD responses to tutor's song, and more pronounced responses to conspecific song primarily in the auditory area field L of the avian forebrain, when compared to birds that produce normal song. These findings are consistent with the presence of a sensory song template critical for song learning in auditory areas of the zebra finch forebrain. In addition, they suggest a relationship between an altered response related to familiarity and/or saliency of song stimuli and the production of variant songs with stuttered syllables.

Behavioral lifetime of human auditory sensory memory predicted by physiological measures.

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Lu, Z L; Williamson, S J; Kaufman, L

1992-12-04

Noninvasive magnetoencephalography makes it possible to identify the cortical area in the human brain whose activity reflects the decay of passive sensory storage of information about auditory stimuli (echoic memory). The lifetime for decay of the neuronal activation trace in primary auditory cortex was found to predict the psychophysically determined duration of memory for the loudness of a tone. Although memory for the loudness of a specific tone is lost, the remembered loudness decays toward the global mean of all of the loudnesses to which a subject is exposed in a series of trials.

Auditory midbrain processing is differentially modulated by auditory and visual cortices: An auditory fMRI study.

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Gao, Patrick P; Zhang, Jevin W; Fan, Shu-Juan; Sanes, Dan H; Wu, Ed X

2015-12-01

The cortex contains extensive descending projections, yet the impact of cortical input on brainstem processing remains poorly understood. In the central auditory system, the auditory cortex contains direct and indirect pathways (via brainstem cholinergic cells) to nuclei of the auditory midbrain, called the inferior colliculus (IC). While these projections modulate auditory processing throughout the IC, single neuron recordings have samples from only a small fraction of cells during stimulation of the corticofugal pathway. Furthermore, assessments of cortical feedback have not been extended to sensory modalities other than audition. To address these issues, we devised blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) paradigms to measure the sound-evoked responses throughout the rat IC and investigated the effects of bilateral ablation of either auditory or visual cortices. Auditory cortex ablation increased the gain of IC responses to noise stimuli (primarily in the central nucleus of the IC) and decreased response selectivity to forward species-specific vocalizations (versus temporally reversed ones, most prominently in the external cortex of the IC). In contrast, visual cortex ablation decreased the gain and induced a much smaller effect on response selectivity. The results suggest that auditory cortical projections normally exert a large-scale and net suppressive influence on specific IC subnuclei, while visual cortical projections provide a facilitatory influence. Meanwhile, auditory cortical projections enhance the midbrain response selectivity to species-specific vocalizations. We also probed the role of the indirect cholinergic projections in the auditory system in the descending modulation process by pharmacologically blocking muscarinic cholinergic receptors. This manipulation did not affect the gain of IC responses but significantly reduced the response selectivity to vocalizations. The results imply that auditory cortical

The significance of a hypoplastic bony canal for the cochlear nerve in patients with sensorineural hearing loss: CT and MRI findings

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Choi, Yoon Jung; Park, Sang Yoo; Kim, Myung Soon; Sung, Ki Jun

2004-01-01

The purpose of this study is to evaluate the significance of the hypoplastic canal for the cochlear nerve in patients with sensorineural hearing loss (SNHL) and the relationship between the hypoplastic bony canal and aplasia or hypoplasia of the cochlear nerve. A retrospective review of high resolution temporal CT(HRCT) and MRI findings was conducted. The narrow bony canal of the cochlear nerve and the relative size of the internal auditory canal were correlated with the cochlear nerve deficiency on MRI. The comparative size of the component nerves (facial, cochlear, superior vestibular, inferior vestibular nerve), and the relative size of the internal auditory canal and the bony canal of the cochlear nerve were measured. The clinical history and the results of the clinical examination were reviewed for each patient. High resolution MRI showed aplasia of the common vestibulocochlear nerve in one patient and a deficiency of the cochlear nerve in 9 patients. These abnormalities occurred in association with a prominent narrowing of the canal for the cochlear nerve and a stenosis of the internal auditory canal, which was observed on temporal bone CT in 9 patients with congenital SNHL. Three patients had normal IAC, despite the presence of a hypoplastic cochlear nerve on the side on which they had SNHL. In one patient, the narrowing of the canal for the cochlear nerve and internal auditory canal were not found to be associated with acquired SNHL. The hypoplastic bony canal for the cochlear nerve might be more highly indicative of congenital cochlear nerve deficiency than that of the narrow internal auditory canal, and the position of the crista falciformis should also be carefully

The significance of a hypoplastic bony canal for the cochlear nerve in patients with sensorineural hearing loss: CT and MRI findings

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Choi, Yoon Jung; Park, Sang Yoo; Kim, Myung Soon; Sung, Ki Jun [College of Medicine, Yonsei Univ., Wonju (Korea, Republic of)

2004-04-01

The purpose of this study is to evaluate the significance of the hypoplastic canal for the cochlear nerve in patients with sensorineural hearing loss (SNHL) and the relationship between the hypoplastic bony canal and aplasia or hypoplasia of the cochlear nerve. A retrospective review of high resolution temporal CT(HRCT) and MRI findings was conducted. The narrow bony canal of the cochlear nerve and the relative size of the internal auditory canal were correlated with the cochlear nerve deficiency on MRI. The comparative size of the component nerves (facial, cochlear, superior vestibular, inferior vestibular nerve), and the relative size of the internal auditory canal and the bony canal of the cochlear nerve were measured. The clinical history and the results of the clinical examination were reviewed for each patient. High resolution MRI showed aplasia of the common vestibulocochlear nerve in one patient and a deficiency of the cochlear nerve in 9 patients. These abnormalities occurred in association with a prominent narrowing of the canal for the cochlear nerve and a stenosis of the internal auditory canal, which was observed on temporal bone CT in 9 patients with congenital SNHL. Three patients had normal IAC, despite the presence of a hypoplastic cochlear nerve on the side on which they had SNHL. In one patient, the narrowing of the canal for the cochlear nerve and internal auditory canal were not found to be associated with acquired SNHL. The hypoplastic bony canal for the cochlear nerve might be more highly indicative of congenital cochlear nerve deficiency than that of the narrow internal auditory canal, and the position of the crista falciformis should also be carefully.

Cervical Vestibular Evoked Myogenic Potential in Hypoglossal Nerve Schwannoma: A Case Report.

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Rajasekaran, Aravind Kumar; Savardekar, Amey Rajan; Shivashankar, Nagaraja Rao

2018-02-01

Schwannoma of the hypoglossal nerve is rare. This case report documents an atypical abnormality of the cervical vestibular evoked myogenic potential (cVEMP) in a patient with schwannoma of the hypoglossal nerve. The observed abnormality was attributed to the proximity of the hypoglossal nerve to the spinal accessory nerve in the medullary cistern and base of the skull. To report cVEMP abnormality in a patient with hypoglossal nerve schwannoma and provide an anatomical correlation for this abnormality. Case report. A 44-yr-old woman. Pure-tone and speech audiometry, tympanometry, acoustic stapedial reflex, auditory brainstem response, and cVEMP testing were performed. The audiological test results were normal except for the absence of cVEMP on the lesion side (right). A cVEMP abnormality indicating a compromised spinal accessory nerve was observed in a patient with hypoglossal nerve schwannoma. This case report highlights the importance of recording cVEMP in relevant neurological conditions and provides clinical proof for the involvement of the spinal accessory nerve in the vestibulocollic reflex pathway. American Academy of Audiology

Auditory working memory predicts individual differences in absolute pitch learning.

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Van Hedger, Stephen C; Heald, Shannon L M; Koch, Rachelle; Nusbaum, Howard C

2015-07-01

Absolute pitch (AP) is typically defined as the ability to label an isolated tone as a musical note in the absence of a reference tone. At first glance the acquisition of AP note categories seems like a perceptual learning task, since individuals must assign a category label to a stimulus based on a single perceptual dimension (pitch) while ignoring other perceptual dimensions (e.g., loudness, octave, instrument). AP, however, is rarely discussed in terms of domain-general perceptual learning mechanisms. This is because AP is typically assumed to depend on a critical period of development, in which early exposure to pitches and musical labels is thought to be necessary for the development of AP precluding the possibility of adult acquisition of AP. Despite this view of AP, several previous studies have found evidence that absolute pitch category learning is, to an extent, trainable in a post-critical period adult population, even if the performance typically achieved by this population is below the performance of a "true" AP possessor. The current studies attempt to understand the individual differences in learning to categorize notes using absolute pitch cues by testing a specific prediction regarding cognitive capacity related to categorization - to what extent does an individual's general auditory working memory capacity (WMC) predict the success of absolute pitch category acquisition. Since WMC has been shown to predict performance on a wide variety of other perceptual and category learning tasks, we predict that individuals with higher WMC should be better at learning absolute pitch note categories than individuals with lower WMC. Across two studies, we demonstrate that auditory WMC predicts the efficacy of learning absolute pitch note categories. These results suggest that a higher general auditory WMC might underlie the formation of absolute pitch categories for post-critical period adults. Implications for understanding the mechanisms that underlie the

Inattentional Deafness: Visual Load Leads to Time-Specific Suppression of Auditory Evoked Responses.

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Molloy, Katharine; Griffiths, Timothy D; Chait, Maria; Lavie, Nilli

2015-12-09

Due to capacity limits on perception, conditions of high perceptual load lead to reduced processing of unattended stimuli (Lavie et al., 2014). Accumulating work demonstrates the effects of visual perceptual load on visual cortex responses, but the effects on auditory processing remain poorly understood. Here we establish the neural mechanisms underlying "inattentional deafness"--the failure to perceive auditory stimuli under high visual perceptual load. Participants performed a visual search task of low (target dissimilar to nontarget items) or high (target similar to nontarget items) load. On a random subset (50%) of trials, irrelevant tones were presented concurrently with the visual stimuli. Brain activity was recorded with magnetoencephalography, and time-locked responses to the visual search array and to the incidental presence of unattended tones were assessed. High, compared to low, perceptual load led to increased early visual evoked responses (within 100 ms from onset). This was accompanied by reduced early (∼ 100 ms from tone onset) auditory evoked activity in superior temporal sulcus and posterior middle temporal gyrus. A later suppression of the P3 "awareness" response to the tones was also observed under high load. A behavioral experiment revealed reduced tone detection sensitivity under high visual load, indicating that the reduction in neural responses was indeed associated with reduced awareness of the sounds. These findings support a neural account of shared audiovisual resources, which, when depleted under load, leads to failures of sensory perception and awareness. The present work clarifies the neural underpinning of inattentional deafness under high visual load. The findings of near-simultaneous load effects on both visual and auditory evoked responses suggest shared audiovisual processing capacity. Temporary depletion of shared capacity in perceptually demanding visual tasks leads to a momentary reduction in sensory processing of auditory

Is the auditory evoked P2 response a biomarker of learning?

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Kelly eTremblay

2014-02-01

Full Text Available Even though auditory training exercises for humans have been shown to improve certain perceptual skills of individuals with and without hearing loss, there is a lack of knowledge pertaining to which aspects of training are responsible for the perceptual gains, and which aspects of perception are changed. To better define how auditory training impacts brain and behavior, electroencephalography and magnetoencephalography have been used to determine the time course and coincidence of cortical modulations associated with different types of training. Here we focus on P1-N1-P2 auditory evoked responses (AEP, as there are consistent reports of gains in P2 amplitude following various types of auditory training experiences; including music and speech-sound training. The purpose of this experiment was to determine if the auditory evoked P2 response is a biomarker of learning. To do this, we taught native English speakers to identify a new pre-voiced temporal cue that is not used phonemically in the English language so that coinciding changes in evoked neural activity could be characterized. To differentiate possible effects of repeated stimulus exposure and a button-pushing task from learning itself, we examined modulations in brain activity in a group of participants who learned to identify the pre-voicing contrast and compared it to participants, matched in time, and stimulus exposure, that did not. The main finding was that the amplitude of the P2 auditory evoked response increased across repeated EEG sessions for all groups, regardless of any change in perceptual performance. What’s more, these effects were retained for months. Changes in P2 amplitude were attributed to changes in neural activity associated with the acquisition process and not the learned outcome itself. A further finding was the expression of a late negativity (LN wave 600-900 ms post-stimulus onset, post-training, exclusively for the group that learned to identify the pre

Effect of neonatal asphyxia on the impairment of the auditory pathway by recording auditory brainstem responses in newborn piglets: a new experimentation model to study the perinatal hypoxic-ischemic damage on the auditory system.

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Francisco Jose Alvarez

Full Text Available Hypoxia-ischemia (HI is a major perinatal problem that results in severe damage to the brain impairing the normal development of the auditory system. The purpose of the present study is to study the effect of perinatal asphyxia on the auditory pathway by recording auditory brain responses in a novel animal experimentation model in newborn piglets.Hypoxia-ischemia was induced to 1.3 day-old piglets by clamping 30 minutes both carotid arteries by vascular occluders and lowering the fraction of inspired oxygen. We compared the Auditory Brain Responses (ABRs of newborn piglets exposed to acute hypoxia/ischemia (n = 6 and a control group with no such exposure (n = 10. ABRs were recorded for both ears before the start of the experiment (baseline, after 30 minutes of HI injury, and every 30 minutes during 6 h after the HI injury.Auditory brain responses were altered during the hypoxic-ischemic insult but recovered 30-60 minutes later. Hypoxia/ischemia seemed to induce auditory functional damage by increasing I-V latencies and decreasing wave I, III and V amplitudes, although differences were not significant.The described experimental model of hypoxia-ischemia in newborn piglets may be useful for studying the effect of perinatal asphyxia on the impairment of the auditory pathway.

Response actions influence the categorization of directions in auditory space

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Marcella de Castro Campos Velten

2015-08-01

Full Text Available Spatial region concepts such as front, back, left and right reflect our typical interaction with space, and the corresponding surrounding regions have different statuses in memory. We examined the representation of spatial directions in the auditory space, specifically in how far natural response actions, such as orientation movements towards a sound source, would affect the categorization of egocentric auditory space. While standing in the middle of a circle with 16 loudspeakers, participants were presented acoustic stimuli coming from the loudspeakers in randomized order, and verbally described their directions by using the concept labels front, back, left, right, front-right, front-left, back-right and back-left. Response actions varied in three blocked conditions: 1 facing front, 2 turning the head and upper body to face the stimulus, and 3 turning the head and upper body plus pointing with the hand and outstretched arm towards the stimulus. In addition to a protocol of the verbal utterances, motion capture and video recording generated a detailed corpus for subsequent analysis of the participants’ behavior. Chi-square tests revealed an effect of response condition for directions within the left and right sides. We conclude that movement-based response actions influence the representation of auditory space, especially within the sides’ regions.

Age and Gender Effects On Auditory Brain Stem Response (ABR

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Yones Lotfi

2012-10-01

Full Text Available Objectives: Auditory Brain Stem Response (ABR is a result of eight nerve and brain stem nuclei stimulation. Several factors may affect the latencies, interpeak latencies and amplitudes in ABR especially sex and age. In this study, age and sex influence on ABR were studied. Methods: This study was performed on 120 cases (60 males and 60 females at Akhavan rehabilitation center of university of welfare and rehabilitation sciences, Tehran, Iran. Cases were divided in three age groups: 18-30, 31-50 and 51-70 years old. Each age group consists of 20 males and 20 females. Age and sex influences on absolute latency of wave I and V, and IPL of I-V were examined. Results: Independent t test showed that females have significantly shorter latency of wave I, V, and IPL I-V latency (P<0.001 than males. Two way ANOVA showed that latency of wave I, V and IPL I-V in 51-70 years old group was significantly higher than 18-30 and 31-50 years old groups (P<0.001 Discussion: According to the results of present study and similar studies, in clinical practice, different norms for older adults and both genders should be established.

Increased Early Processing of Task-Irrelevant Auditory Stimuli in Older Adults.

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Erich S Tusch

Full Text Available The inhibitory deficit hypothesis of cognitive aging posits that older adults' inability to adequately suppress processing of irrelevant information is a major source of cognitive decline. Prior research has demonstrated that in response to task-irrelevant auditory stimuli there is an age-associated increase in the amplitude of the N1 wave, an ERP marker of early perceptual processing. Here, we tested predictions derived from the inhibitory deficit hypothesis that the age-related increase in N1 would be 1 observed under an auditory-ignore, but not auditory-attend condition, 2 attenuated in individuals with high executive capacity (EC, and 3 augmented by increasing cognitive load of the primary visual task. ERPs were measured in 114 well-matched young, middle-aged, young-old, and old-old adults, designated as having high or average EC based on neuropsychological testing. Under the auditory-ignore (visual-attend task, participants ignored auditory stimuli and responded to rare target letters under low and high load. Under the auditory-attend task, participants ignored visual stimuli and responded to rare target tones. Results confirmed an age-associated increase in N1 amplitude to auditory stimuli under the auditory-ignore but not auditory-attend task. Contrary to predictions, EC did not modulate the N1 response. The load effect was the opposite of expectation: the N1 to task-irrelevant auditory events was smaller under high load. Finally, older adults did not simply fail to suppress the N1 to auditory stimuli in the task-irrelevant modality; they generated a larger response than to identical stimuli in the task-relevant modality. In summary, several of the study's findings do not fit the inhibitory-deficit hypothesis of cognitive aging, which may need to be refined or supplemented by alternative accounts.

Absence of both auditory evoked potentials and auditory percepts dependent on timing cues.

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Starr, A; McPherson, D; Patterson, J; Don, M; Luxford, W; Shannon, R; Sininger, Y; Tonakawa, L; Waring, M

1991-06-01

An 11-yr-old girl had an absence of sensory components of auditory evoked potentials (brainstem, middle and long-latency) to click and tone burst stimuli that she could clearly hear. Psychoacoustic tests revealed a marked impairment of those auditory perceptions dependent on temporal cues, that is, lateralization of binaural clicks, change of binaural masked threshold with changes in signal phase, binaural beats, detection of paired monaural clicks, monaural detection of a silent gap in a sound, and monaural threshold elevation for short duration tones. In contrast, auditory functions reflecting intensity or frequency discriminations (difference limens) were only minimally impaired. Pure tone audiometry showed a moderate (50 dB) bilateral hearing loss with a disproportionate severe loss of word intelligibility. Those auditory evoked potentials that were preserved included (1) cochlear microphonics reflecting hair cell activity; (2) cortical sustained potentials reflecting processing of slowly changing signals; and (3) long-latency cognitive components (P300, processing negativity) reflecting endogenous auditory cognitive processes. Both the evoked potential and perceptual deficits are attributed to changes in temporal encoding of acoustic signals perhaps occurring at the synapse between hair cell and eighth nerve dendrites. The results from this patient are discussed in relation to previously published cases with absent auditory evoked potentials and preserved hearing.

Representation of acoustic signals in the eighth nerve of the Tokay gecko: I. Pure tones.

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Sams-Dodd, F; Capranica, R R

1994-06-01

A systematic study of the encoding properties of 146 auditory nerve fibers in the Tokay gecko (Gekko gecko, L) was conducted with respect to pure tones and two-tone rate suppression. Our aim was a comprehensive understanding of the peripheral encoding of simple tonal stimuli and their representation by temporal synchronization and spike rate codes as a prelude to subsequent studies of more complex signals. Auditory nerve fibers in the Tokay gecko have asymmetrical, V-shaped excitatory tuning curves with best excitatory frequencies that range from 200-5100 Hz and thresholds between 4-35 dB SPL. A low-frequency excitatory 'tail' extends far into the low-frequency range and two-tone suppression is present only on the high frequency side of the tuning curve. The response properties to pure tones at different loci within a tuning curve can differ greatly, due to evident interactions between the representations of temporal, spectral and intensity stimulus features. For frequencies below 1250 Hz, pure tones are encoded by both temporal synchronization and spike rate codes, whereas above this frequency a fiber's ability to encode the waveform periodicity is lost and only a rate code predominates. These complimentary representations within a tuning curve raise fundamental issues which need to be addressed in interpreting how more complex, bioacoustic communication signals are represented in the peripheral and central auditory system. And since auditory nerve fibers in the Tokay gecko exhibit tonal sensitivity, selective frequency tuning, and iso-intensity and iso-frequency contours that seem comparable to similar measures in birds and mammals, these issues likely apply to most higher vertebrates in general. The simpler wiring diagram of the reptilian auditory system, coupled with the Tokay gecko's remarkable vocalizations, make this animal a good evolutionary model in which to experimentally explore the encoding of more complex sounds of communicative significance.

Benefits and detriments of unilateral cochlear implant use on bilateral auditory development in children who are deaf

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Karen A. Gordon

2013-10-01

Full Text Available We have explored both the benefits and detriments of providing electrical input through a cochlear implant in one ear to the auditory system of young children. A cochlear implant delivers electrical pulses to stimulate the auditory nerve, providing children who are deaf with access to sound. The goals of implantation are to restrict reorganization of the deprived immature auditory brain and promote development of hearing and spoken language. It is clear that limiting the duration of deprivation is a key factor. Additional considerations are the onset, etiology, and use of residual hearing as each of these can have unique effects on auditory development in the pre-implant period. New findings show that many children receiving unilateral cochlear implants are developing mature-like brainstem and thalamo-cortical responses to sound with long term use despite these sources of variability; however, there remain considerable abnormalities in cortical function. The most apparent, determined by implanting the other ear and measuring responses to acute stimulation, is a loss of normal cortical response from the deprived ear. Recent data reveal that this can be avoided in children by early implantation of both ears simultaneously or with limited delay. We conclude that auditory development requires input early in development and from both ears.

Predictors of response to occipital nerve stimulation in refractory chronic headache.

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Miller, Sarah; Watkins, Laurence; Matharu, Manjit

2017-01-01

Background Occipital nerve stimulation is a promising treatment for refractory chronic headache disorders, but is invasive and costly. Identifying predictors of response would be useful in selecting patients. We present the results of an open-label prospective cohort study of 100 patients (35 chronic migraine, 33 chronic cluster headache, 20 short-lasting unilateral neuralgiform headache attacks and 12 hemicrania continua) undergoing occipital nerve stimulation, using a multivariate binary regression analysis to identify predictors of response. Results Response rate of the cohort was 48%. Multivariate analysis showed short lasting unilateral neuralgiform headache attacks (OR 6.71; 95% CI 1.49-30.05; p = 0.013) and prior response to greater occipital nerve block (OR 4.22; 95% CI 1.35-13.21; p = 0.013) were associated with increased likelihood of response. Presence of occipital pain (OR 0.27; 95% CI 0.09-0.76; p = 0.014) and the presence of severe anxiety and/or depression (as measured on hospital anxiety and depression score) at time of implantation (OR 0.32; 95% CI 0.11-0.91; p = 0.032) were associated with reduced likelihood of response. Conclusion Possible clinical predictors of response to occipital nerve stimulation for refractory chronic headaches have been identified. Our data shows that those with short-lasting unilateral neuralgiform headache attacks respond better than those with chronic migraine, and that a prior response to greater occipital nerve block is associated with positive outcomes. This study suggests that the presence of occipital pain and severe mood disorder at time of implant are both associated with poor outcomes to occipital nerve stimulation.

Diminished Auditory Responses during NREM Sleep Correlate with the Hierarchy of Language Processing.

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Meytal Wilf

Full Text Available Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations.

Diminished Auditory Responses during NREM Sleep Correlate with the Hierarchy of Language Processing.

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Wilf, Meytal; Ramot, Michal; Furman-Haran, Edna; Arzi, Anat; Levkovitz, Yechiel; Malach, Rafael

2016-01-01

Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI) during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM) sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG) cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations.

Facial Nerve Schwannoma of the Cerebellopontine Angle: A Diagnostic Challenge

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Lassaletta, Luis; Roda, José María; Frutos, Remedios; Patrón, Mercedes; Gavilán, Javier

2002-01-01

Facial nerve schwannomas are rare lesions that may involve any segment of the facial nerve. Because of their rarity and the lack of a consistent clinical and radiological pattern, facial nerve schwannomas located at the cerebellopontine angle (CPA) and internal auditory canal (IAC) represent a diagnostic and therapeutic challenge for clinicians. In this report, a case of a CPA/IAC facial nerve schwannoma is presented. Contemporary diagnosis and management of this rare lesion are analyzed.

Functional significance of the electrocorticographic auditory responses in the premotor cortex

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Kazuyo eTanji

2015-03-01

Full Text Available Other than well-known motor activities in the precentral gyrus, functional magnetic resonance imaging (fMRI studies have found that the ventral part of the precentral gyrus is activated in response to linguistic auditory stimuli. It has been proposed that the premotor cortex in the precentral gyrus is responsible for the comprehension of speech, but the precise function of this area is still debated because patients with frontal lesions that include the precentral gyrus do not exhibit disturbances in speech comprehension. We report on a patient who underwent resection of the tumor in the precentral gyrus with electrocorticographic recordings while she performed the verb generation task during awake brain craniotomy. Consistent with previous fMRI studies, high-gamma band auditory activity was observed in the precentral gyrus. Due to the location of the tumor, the patient underwent resection of the auditory responsive precentral area which resulted in the post-operative expression of a characteristic articulatory disturbance known as apraxia of speech (AOS. The language function of the patient was otherwise preserved and she exhibited intact comprehension of both spoken and written language. The present findings demonstrated that a lesion restricted to the ventral precentral gyrus is sufficient for the expression of AOS and suggest that the auditory-responsive area plays an important role in the execution of fluent speech rather than the comprehension of speech. These findings also confirm that the function of the premotor area is predominantly motor in nature and its sensory responses is more consistent with the ‘sensory theory of speech production’, in which it was proposed that sensory representations are used to guide motor-articulatory processes.

Auditory cortical and hippocampal-system mismatch responses to duration deviants in urethane-anesthetized rats.

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Timo Ruusuvirta

Full Text Available Any change in the invariant aspects of the auditory environment is of potential importance. The human brain preattentively or automatically detects such changes. The mismatch negativity (MMN of event-related potentials (ERPs reflects this initial stage of auditory change detection. The origin of MMN is held to be cortical. The hippocampus is associated with a later generated P3a of ERPs reflecting involuntarily attention switches towards auditory changes that are high in magnitude. The evidence for this cortico-hippocampal dichotomy is scarce, however. To shed further light on this issue, auditory cortical and hippocampal-system (CA1, dentate gyrus, subiculum local-field potentials were recorded in urethane-anesthetized rats. A rare tone in duration (deviant was interspersed with a repeated tone (standard. Two standard-to-standard (SSI and standard-to-deviant (SDI intervals (200 ms vs. 500 ms were applied in different combinations to vary the observability of responses resembling MMN (mismatch responses. Mismatch responses were observed at 51.5-89 ms with the 500-ms SSI coupled with the 200-ms SDI but not with the three remaining combinations. Most importantly, the responses appeared in both the auditory-cortical and hippocampal locations. The findings suggest that the hippocampus may play a role in (cortical manifestation of MMN.

Explaining the high voice superiority effect in polyphonic music: evidence from cortical evoked potentials and peripheral auditory models.

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Trainor, Laurel J; Marie, Céline; Bruce, Ian C; Bidelman, Gavin M

2014-02-01

Natural auditory environments contain multiple simultaneously-sounding objects and the auditory system must parse the incoming complex sound wave they collectively create into parts that represent each of these individual objects. Music often similarly requires processing of more than one voice or stream at the same time, and behavioral studies demonstrate that human listeners show a systematic perceptual bias in processing the highest voice in multi-voiced music. Here, we review studies utilizing event-related brain potentials (ERPs), which support the notions that (1) separate memory traces are formed for two simultaneous voices (even without conscious awareness) in auditory cortex and (2) adults show more robust encoding (i.e., larger ERP responses) to deviant pitches in the higher than in the lower voice, indicating better encoding of the former. Furthermore, infants also show this high-voice superiority effect, suggesting that the perceptual dominance observed across studies might result from neurophysiological characteristics of the peripheral auditory system. Although musically untrained adults show smaller responses in general than musically trained adults, both groups similarly show a more robust cortical representation of the higher than of the lower voice. Finally, years of experience playing a bass-range instrument reduces but does not reverse the high voice superiority effect, indicating that although it can be modified, it is not highly neuroplastic. Results of new modeling experiments examined the possibility that characteristics of middle-ear filtering and cochlear dynamics (e.g., suppression) reflected in auditory nerve firing patterns might account for the higher-voice superiority effect. Simulations show that both place and temporal AN coding schemes well-predict a high-voice superiority across a wide range of interval spacings and registers. Collectively, we infer an innate, peripheral origin for the higher-voice superiority observed in human

Naftidrofuryl affects neurite regeneration by injured adult auditory neurons.

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Lefebvre, P P; Staecker, H; Moonen, G; van de Water, T R

1993-07-01

Afferent auditory neurons are essential for the transmission of auditory information from Corti's organ to the central auditory pathway. Auditory neurons are very sensitive to acute insult and have a limited ability to regenerate injured neuronal processes. Therefore, these neurons appear to be a limiting factor in restoration of hearing function following an injury to the peripheral auditory receptor. In a previous study nerve growth factor (NGF) was shown to stimulate neurite repair but not survival of injured auditory neurons. In this study, we have demonstrated a neuritogenesis promoting effect of naftidrofuryl in an vitro model for injury to adult auditory neurons, i.e. dissociated cell cultures of adult rat spiral ganglia. Conversely, naftidrofuryl did not have any demonstrable survival promoting effect on these in vitro preparations of injured auditory neurons. The potential uses of this drug as a therapeutic agent in acute diseases of the inner ear are discussed in the light of these observations.

Generation of human auditory steady-state responses (SSRs). II: Addition of responses to individual stimuli.

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Santarelli, R; Maurizi, M; Conti, G; Ottaviani, F; Paludetti, G; Pettorossi, V E

1995-03-01

In order to investigate the generation of the 40 Hz steady-state response (SSR), auditory potentials evoked by clicks were recorded in 16 healthy subjects in two stimulating conditions. Firstly, repetition rates of 7.9 and 40 Hz were used to obtain individual middle latency responses (MLRs) and 40 Hz-SSRs, respectively. In the second condition, eight click trains were presented at a 40 Hz repetition rate and an inter-train interval of 126 ms. We extracted from the whole train response: (1) the response-segment taking place after the last click of the train (last click response, LCR), (2) a modified LCR (mLCR) obtained by clearing the LCR from the amplitude enhancement due to the overlapping of the responses to the clicks preceding the last within the stimulus train. In comparison to MLRs, the most relevant feature of the evoked activity following the last click of the train (LCRs, mLCRs) was the appearance in the 50-110 ms latency range of one (in 11 subjects) or two (in 2 subjects) additional positive-negative deflections having the same periodicity as that of MLR waves. The grand average (GA) of the 40 Hz-SSRs was compared with three predictions synthesized by superimposing: (1) the GA of MLRs, (2) the GA of LCRs, (3) the GA of mLCRs. Both the MLR and mLCR predictions reproduced the recorded signal in amplitude while the LCR prediction amplitude resulted almost twice that of the 40 Hz-SSR. With regard to the phase, the MLR, LCR and mLCR closely predicted the recorded signal. Our findings confirm the effectiveness of the linear addition mechanism in the generation of the 40 Hz-SSR. However the responses to individual stimuli within the 40 Hz-SSR differ from MLRs because of additional periodic activity. These results suggest that phenomena related to the resonant frequency of the activated system may play a role in the mechanisms which interact to generate the 40 Hz-SSR.

From sensation to percept: the neural signature of auditory event-related potentials.

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Joos, Kathleen; Gilles, Annick; Van de Heyning, Paul; De Ridder, Dirk; Vanneste, Sven

2014-05-01

An external auditory stimulus induces an auditory sensation which may lead to a conscious auditory perception. Although the sensory aspect is well known, it is still a question how an auditory stimulus results in an individual's conscious percept. To unravel the uncertainties concerning the neural correlates of a conscious auditory percept, event-related potentials may serve as a useful tool. In the current review we mainly wanted to shed light on the perceptual aspects of auditory processing and therefore we mainly focused on the auditory late-latency responses. Moreover, there is increasing evidence that perception is an active process in which the brain searches for the information it expects to be present, suggesting that auditory perception requires the presence of both bottom-up, i.e. sensory and top-down, i.e. prediction-driven processing. Therefore, the auditory evoked potentials will be interpreted in the context of the Bayesian brain model, in which the brain predicts which information it expects and when this will happen. The internal representation of the auditory environment will be verified by sensation samples of the environment (P50, N100). When this incoming information violates the expectation, it will induce the emission of a prediction error signal (Mismatch Negativity), activating higher-order neural networks and inducing the update of prior internal representations of the environment (P300). Copyright © 2014 Elsevier Ltd. All rights reserved.

Brainstem response audiometry in the determination of low-frequency hearing loss : a study of various methods for frequency-specific ABR-threshold assessment

NARCIS (Netherlands)

E.A.G.J. Conijn

1992-01-01

textabstractBrainstem Electric Response Audiometry (BERA) is a method to visualize some of the electric activity generated in the auditory nerve and the brainstem during the processing of sound. The amplitude of the Auditory Brainstem Response (ABR) is very small (0.05-0.5 flV). The potentials

Adaptation, saturation, and physiological masking in single auditory-nerve fibers.

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Smith, R L

1979-01-01

Results are reviewed concerning some effects, at a units's characteristic frequency, of a short-term conditioning stimulus on the responses to perstimulatory and poststimulatory test tones. A phenomenological equation is developed from the poststimulatory results and shown to be consistent with the perstimulatory results. According to the results and equation, the response to a test tone equals the unconditioned or unadapted response minus the decrement produced by adaptation to the conditioning tone. Furthermore, the decrement is proportional to the driven response to the conditioning tone and does not depend on sound intensity per se. The equation has a simple interpretation in terms of two processes in cascade--a static saturating nonlinearity followed by additive adaptation. Results are presented to show that this functional model is sufficient to account for the "physiological masking" produced by wide-band backgrounds. According to this interpretation, a sufficiently intense background produces saturation. Consequently, a superimposed test tone cause no change in response. In addition, when the onset of the background precedes the onset of the test tone, the total firing rate is reduced by adaptation. Evidence is reviewed concerning the possible correspondence between the variables in the model and intracellular events in the auditory periphery.

Reduced object related negativity response indicates impaired auditory scene analysis in adults with autistic spectrum disorder

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Veema Lodhia

2014-02-01

Full Text Available Auditory Scene Analysis provides a useful framework for understanding atypical auditory perception in autism. Specifically, a failure to segregate the incoming acoustic energy into distinct auditory objects might explain the aversive reaction autistic individuals have to certain auditory stimuli or environments. Previous research with non-autistic participants has demonstrated the presence of an Object Related Negativity (ORN in the auditory event related potential that indexes pre-attentive processes associated with auditory scene analysis. Also evident is a later P400 component that is attention dependent and thought to be related to decision-making about auditory objects. We sought to determine whether there are differences between individuals with and without autism in the levels of processing indexed by these components. Electroencephalography (EEG was used to measure brain responses from a group of 16 autistic adults, and 16 age- and verbal-IQ-matched typically-developing adults. Auditory responses were elicited using lateralized dichotic pitch stimuli in which inter-aural timing differences create the illusory perception of a pitch that is spatially separated from a carrier noise stimulus. As in previous studies, control participants produced an ORN in response to the pitch stimuli. However, this component was significantly reduced in the participants with autism. In contrast, processing differences were not observed between the groups at the attention-dependent level (P400. These findings suggest that autistic individuals have difficulty segregating auditory stimuli into distinct auditory objects, and that this difficulty arises at an early pre-attentive level of processing.

α-Synuclein deficiency and efferent nerve degeneration in the mouse cochlea: a possible cause of early-onset presbycusis.

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Park, S N; Back, S A; Choung, Y H; Kim, H L; Akil, O; Lustig, L R; Park, K H; Yeo, S W

2011-11-01

Efferent nerves under the outer hair cells (OHCs) play a role in the protection of these cells from loud stimuli. Previously, we showed that cochlear α-synuclein expression is localized to efferent auditory synapses at the base of the OHCs. To prove our hypothesis that α-synuclein deficiency and efferent auditory deficit might be a cause of hearing loss, we compared the morphology of efferent nerve endings and α-synuclein expression within the cochleae of two mouse models of presbycusis. Comparative animal study of presbycusis. The C57BL/6J(C57) mouse strain, a well-known model of early-onset hearing loss, and the CBA mouse strain, a model of relatively late-onset hearing loss, were examined. Auditory brainstem responses and distortion product otoacoustic emissions were recorded, and cochlear morphology with efferent nerve ending was compared. Western blotting was used to examine α-synuclein expression in the cochlea. Compared with CBA mice, C57 mice showed earlier onset high-frequency hearing loss and decreased function in OHCs, especially within high-frequency regions. C57 mice demonstrated more severe pathologic changes within the cochlea, particularly within the basal turn, than CBA mice of the same age. Weaker α-synuclein and synaptophysin expression in the efferent nerve endings and cochlear homogenates in C57 mice was observed. Our results support the hypothesis that efferent nerve degeneration, possibly due to differential α-synuclein expression, is a potential cause of early-onset presbycusis. Further studies at the cellular level are necessary to verify our results. Copyright © 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

MRI enhancement of the facial nerve with Gd-DTPA, 2; Investigation of enhanced nerve portions in patients with facial palsy

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Yanagida, Masahiro [Kansai Medical School, Moriguchi, Osaka (Japan)

1993-08-01

We performed enhanced MRI using Gd-DTPA in 84 patients with facial palsy. After assessing enhancement of the normal facial nerve, we examined enhancement in patients with Bell's palsy and Ramsay Hunt syndrome. In 95% of patients with Bell's palsy, enhancement was obtained in the distal IAC and labyrinthine portions. In 72%, enhancement was significant from the distal IAC portion through the vertical portion. In some of the patients who underwent enhanced MRI twice, increased signal intensity was observed in distal portions such as the vertical portion. In many cases of Ramsay Hunt syndrome, enhancement was seen extensively in the IAC portion through the vertical portion. In the subjects with internal auditory symptoms such as vertigo and tinnitus, enhancement of the IAC portion was seen not only in the facial nerve but also in the vestibular and the cochlear nerves. These results suggest that the vascular permeability of lesions in Bell's palsy may be increased from the distal IAC portion to the vertical portion. Judging from the present findings with Ramsay Hunt syndrome, symptoms related to the enhanced portions suggest that accompanying internal auditory symptoms occur due to inflammation of the IAC portions of cochlear and vestibular nerves. (author).

Magnetoencephalographic Imaging of Auditory and Somatosensory Cortical Responses in Children with Autism and Sensory Processing Dysfunction

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Carly Demopoulos

2017-05-01

Full Text Available This study compared magnetoencephalographic (MEG imaging-derived indices of auditory and somatosensory cortical processing in children aged 8–12 years with autism spectrum disorder (ASD; N = 18, those with sensory processing dysfunction (SPD; N = 13 who do not meet ASD criteria, and typically developing control (TDC; N = 19 participants. The magnitude of responses to both auditory and tactile stimulation was comparable across all three groups; however, the M200 latency response from the left auditory cortex was significantly delayed in the ASD group relative to both the TDC and SPD groups, whereas the somatosensory response of the ASD group was only delayed relative to TDC participants. The SPD group did not significantly differ from either group in terms of somatosensory latency, suggesting that participants with SPD may have an intermediate phenotype between ASD and TDC with regard to somatosensory processing. For the ASD group, correlation analyses indicated that the left M200 latency delay was significantly associated with performance on the WISC-IV Verbal Comprehension Index as well as the DSTP Acoustic-Linguistic index. Further, these cortical auditory response delays were not associated with somatosensory cortical response delays or cognitive processing speed in the ASD group, suggesting that auditory delays in ASD are domain specific rather than associated with generalized processing delays. The specificity of these auditory delays to the ASD group, in addition to their correlation with verbal abilities, suggests that auditory sensory dysfunction may be implicated in communication symptoms in ASD, motivating further research aimed at understanding the impact of sensory dysfunction on the developing brain.

Auditory-visual integration in fields of the auditory cortex.

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Kubota, Michinori; Sugimoto, Shunji; Hosokawa, Yutaka; Ojima, Hisayuki; Horikawa, Junsei

2017-03-01

While multimodal interactions have been known to exist in the early sensory cortices, the response properties and spatiotemporal organization of these interactions are poorly understood. To elucidate the characteristics of multimodal sensory interactions in the cerebral cortex, neuronal responses to visual stimuli with or without auditory stimuli were investigated in core and belt fields of guinea pig auditory cortex using real-time optical imaging with a voltage-sensitive dye. On average, visual responses consisted of short excitation followed by long inhibition. Although visual responses were observed in core and belt fields, there were regional and temporal differences in responses. The most salient visual responses were observed in the caudal belt fields, especially posterior (P) and dorsocaudal belt (DCB) fields. Visual responses emerged first in fields P and DCB and then spread rostroventrally to core and ventrocaudal belt (VCB) fields. Absolute values of positive and negative peak amplitudes of visual responses were both larger in fields P and DCB than in core and VCB fields. When combined visual and auditory stimuli were applied, fields P and DCB were more inhibited than core and VCB fields beginning approximately 110 ms after stimuli. Correspondingly, differences between responses to auditory stimuli alone and combined audiovisual stimuli became larger in fields P and DCB than in core and VCB fields after approximately 110 ms after stimuli. These data indicate that visual influences are most salient in fields P and DCB, which manifest mainly as inhibition, and that they enhance differences in auditory responses among fields. Copyright © 2017 Elsevier B.V. All rights reserved.

Distraction task rather than focal attention modulates gamma activity associated with auditory steady-state responses (ASSRs)

DEFF Research Database (Denmark)

Griskova-Bulanova, Inga; Ruksenas, Osvaldas; Dapsys, Kastytis

2011-01-01

To explore the modulation of auditory steady-state response (ASSR) by experimental tasks, differing in attentional focus and arousal level.......To explore the modulation of auditory steady-state response (ASSR) by experimental tasks, differing in attentional focus and arousal level....

[Impact of hypoglycemic episodes on nerves conduction and auditory and visual evoked potentials in children with type 1 diabetes].

Science.gov (United States)

Wysocka-Mincewicz, Marta; Trippenbach-Dulska, Hanna; Emeryk-Szajewska, Barbara; Zakrzewska-Pniewska, Beata; Kochanek, Krzysztof; Pańkowska, Ewa

2007-01-01

Hypoglycemia is an acute disturbance of energy, especially impacting the central nervous system, but direct influence on peripheral nervous function is not detected. The aim of the study was to establish the influence of hypoglycemic moderate and severe episodes on the function of peripheral nerves, hearing and visual pathway. 97 children with type 1 diabetes (mean age 15.4+/-2.16 years, mean duration of diabetes 8.11+/-2.9 years, mean HbA1c 8,58+/-1.06%), at least 10 years old and with at least 3 years duration of diabetes, were included to study. Nerve conduction studies, visual (VEP) and auditory (ABR) evoked potentials were performed with standard surface stimulating and recording techniques. Moderate hypoglycemic episodes were defined as events of low glycemia requiring help of another person but without loss of consciousness and/or convulsions but recurrent frequently in at least one year. Severe hypoglycemia was defined as events with loss of consciousness and/or convulsions. Univariate ANOVA tests of significance or H Kruskal-Wallis test were used, depending on normality of distribution. The subgroups with a history of hypoglycemic episodes had significant delay in all conduction parameters in the sural nerve (amplitude pwave III latency and interval I-III in subgroups with episodes of hypoglycemia (pwave III and interval I-III. Frequent moderate hypoglycemic episodes were strong risk factors for damage of the peripheral and central nervous systems, comparable with impact of several severe hypoglycemias.

Human pupillary dilation response to deviant auditory stimuli: Effects of stimulus properties and voluntary attention

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Hsin-I eLiao

2016-02-01

Full Text Available A unique sound that deviates from a repetitive background sound induces signature neural responses, such as mismatch negativity and novelty P3 response in electro-encephalography studies. Here we show that a deviant auditory stimulus induces a human pupillary dilation response (PDR that is sensitive to the stimulus properties and irrespective whether attention is directed to the sounds or not. In an auditory oddball sequence, we used white noise and 2000-Hz tones as oddballs against repeated 1000-Hz tones. Participants’ pupillary responses were recorded while they listened to the auditory oddball sequence. In Experiment 1, they were not involved in any task. Results show that pupils dilated to the noise oddballs for approximately 4 s, but no such PDR was found for the 2000-Hz tone oddballs. In Experiments 2, two types of visual oddballs were presented synchronously with the auditory oddballs. Participants discriminated the auditory or visual oddballs while trying to ignore stimuli from the other modality. The purpose of this manipulation was to direct attention to or away from the auditory sequence. In Experiment 3, the visual oddballs and the auditory oddballs were always presented asynchronously to prevent residuals of attention on to-be-ignored oddballs due to the concurrence with the attended oddballs. Results show that pupils dilated to both the noise and 2000-Hz tone oddballs in all conditions. Most importantly, PDRs to noise were larger than those to the 2000-Hz tone oddballs regardless of the attention condition in both experiments. The overall results suggest that the stimulus-dependent factor of the PDR appears to be independent of attention.

Human Pupillary Dilation Response to Deviant Auditory Stimuli: Effects of Stimulus Properties and Voluntary Attention.

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Liao, Hsin-I; Yoneya, Makoto; Kidani, Shunsuke; Kashino, Makio; Furukawa, Shigeto

2016-01-01

A unique sound that deviates from a repetitive background sound induces signature neural responses, such as mismatch negativity and novelty P3 response in electro-encephalography studies. Here we show that a deviant auditory stimulus induces a human pupillary dilation response (PDR) that is sensitive to the stimulus properties and irrespective whether attention is directed to the sounds or not. In an auditory oddball sequence, we used white noise and 2000-Hz tones as oddballs against repeated 1000-Hz tones. Participants' pupillary responses were recorded while they listened to the auditory oddball sequence. In Experiment 1, they were not involved in any task. Results show that pupils dilated to the noise oddballs for approximately 4 s, but no such PDR was found for the 2000-Hz tone oddballs. In Experiments 2, two types of visual oddballs were presented synchronously with the auditory oddballs. Participants discriminated the auditory or visual oddballs while trying to ignore stimuli from the other modality. The purpose of this manipulation was to direct attention to or away from the auditory sequence. In Experiment 3, the visual oddballs and the auditory oddballs were always presented asynchronously to prevent residuals of attention on to-be-ignored oddballs due to the concurrence with the attended oddballs. Results show that pupils dilated to both the noise and 2000-Hz tone oddballs in all conditions. Most importantly, PDRs to noise were larger than those to the 2000-Hz tone oddballs regardless of the attention condition in both experiments. The overall results suggest that the stimulus-dependent factor of the PDR appears to be independent of attention.

[Facial nerve neurinomas].

Science.gov (United States)

Sokołowski, Jacek; Bartoszewicz, Robert; Morawski, Krzysztof; Jamróz, Barbara; Niemczyk, Kazimierz

2013-01-01

Evaluation of diagnostic, surgical technique, treatment results facial nerve neurinomas and its comparison with literature was the main purpose of this study. Seven cases of patients (2005-2011) with facial nerve schwannomas were included to retrospective analysis in the Department of Otolaryngology, Medical University of Warsaw. All patients were assessed with history of the disease, physical examination, hearing tests, computed tomography and/or magnetic resonance imaging, electronystagmography. Cases were observed in the direction of potential complications and recurrences. Neurinoma of the facial nerve occurred in the vertical segment (n=2), facial nerve geniculum (n=1) and the internal auditory canal (n=4). The symptoms observed in patients were analyzed: facial nerve paresis (n=3), hearing loss (n=2), dizziness (n=1). Magnetic resonance imaging and computed tomography allowed to confirm the presence of the tumor and to assess its staging. Schwannoma of the facial nerve has been surgically removed using the middle fossa approach (n=5) and by antromastoidectomy (n=2). Anatomical continuity of the facial nerve was achieved in 3 cases. In the twelve months after surgery, facial nerve paresis was rated at level II-III° HB. There was no recurrence of the tumor in radiological observation. Facial nerve neurinoma is a rare tumor. Currently surgical techniques allow in most cases, the radical removing of the lesion and reconstruction of the VII nerve function. The rate of recurrence is low. A tumor of the facial nerve should be considered in the differential diagnosis of nerve VII paresis. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

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

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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.

The auriculotemporal nerve in etiology of migraine headaches: compression points and anatomical variations.

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Chim, Harvey; Okada, Haruko C; Brown, Matthew S; Alleyne, Brendan; Liu, Mengyuan T; Zwiebel, Samantha; Guyuron, Bahman

2012-08-01

The auriculotemporal nerve has been identified as one of the peripheral trigger sites for migraine headaches. However, its distal course is poorly mapped following emergence from the parotid gland. In addition, a reliable anatomical landmark for locating the potential compression points along the course of the nerve during surgery has not been sufficiently described. Twenty hemifaces on 10 fresh cadavers were dissected to trace the course of the auriculotemporal nerve from the inferior border of the zygomatic arch to its termination in the temporal scalp. The compression points were mapped and the distances were measured from the most anterosuperior point of the external auditory meatus, which was used as a fixed anatomical landmark. Three potential compression points along the course of the auriculotemporal nerve were identified. Compression points 1 and 2 corresponded to preauricular fascial bands. Compression point 1 was centered 13.1±5.9 mm anterior and 5.0±7.0 mm superior to the most anterosuperior point of the external auditory meatus, whereas compression point 2 was centered at 11.9±6.0 mm anterior and 17.2±10.4 mm superior to the most anterosuperior point of the external auditory meatus. A significant relationship was found between the auriculotemporal nerve and superficial temporal artery (compression point 3) in 80 percent of hemifaces, with three patterns of interaction: a single site of artery crossing over the nerve (62.5 percent), a helical intertwining relationship (18.8 percent), and nerve crossing over the artery (18.8 percent). Findings from this cadaver study provide information relevant to the operative localization of potential compression points along the auriculotemporal nerve.

Reversible induction of phantom auditory sensations through simulated unilateral hearing loss.

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Roland Schaette

Full Text Available Tinnitus, a phantom auditory sensation, is associated with hearing loss in most cases, but it is unclear if hearing loss causes tinnitus. Phantom auditory sensations can be induced in normal hearing listeners when they experience severe auditory deprivation such as confinement in an anechoic chamber, which can be regarded as somewhat analogous to a profound bilateral hearing loss. As this condition is relatively uncommon among tinnitus patients, induction of phantom sounds by a lesser degree of auditory deprivation could advance our understanding of the mechanisms of tinnitus. In this study, we therefore investigated the reporting of phantom sounds after continuous use of an earplug. 18 healthy volunteers with normal hearing wore a silicone earplug continuously in one ear for 7 days. The attenuation provided by the earplugs simulated a mild high-frequency hearing loss, mean attenuation increased from 30 dB at 3 and 4 kHz. 14 out of 18 participants reported phantom sounds during earplug use. 11 participants presented with stable phantom sounds on day 7 and underwent tinnitus spectrum characterization with the earplug still in place. The spectra showed that the phantom sounds were perceived predominantly as high-pitched, corresponding to the frequency range most affected by the earplug. In all cases, the auditory phantom disappeared when the earplug was removed, indicating a causal relation between auditory deprivation and phantom sounds. This relation matches the predictions of our computational model of tinnitus development, which proposes a possible mechanism by which a stabilization of neuronal activity through homeostatic plasticity in the central auditory system could lead to the development of a neuronal correlate of tinnitus when auditory nerve activity is reduced due to the earplug.

The Auditory Enhancement Effect is Not Reflected in the 80-Hz Auditory Steady-State Response

OpenAIRE

Carcagno, Samuele; Plack, Christopher J.; Portron, Arthur; Semal, Catherine; Demany, Laurent

2014-01-01

The perceptual salience of a target tone presented in a multitone background is increased by the presentation of a precursor sound consisting of the multitone background alone. It has been proposed that this “enhancement” phenomenon results from an effective amplification of the neural response to the target tone. In this study, we tested this hypothesis in humans, by comparing the auditory steady-state response (ASSR) to a target tone that was enhanced by a precursor sound with the ASSR to a...

Neural Hyperactivity of the Central Auditory System in Response to Peripheral Damage

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Yi Zhao

2016-01-01

Full Text Available It is increasingly appreciated that cochlear pathology is accompanied by adaptive responses in the central auditory system. The cause of cochlear pathology varies widely, and it seems that few commonalities can be drawn. In fact, despite intricate internal neuroplasticity and diverse external symptoms, several classical injury models provide a feasible path to locate responses to different peripheral cochlear lesions. In these cases, hair cell damage may lead to considerable hyperactivity in the central auditory pathways, mediated by a reduction in inhibition, which may underlie some clinical symptoms associated with hearing loss, such as tinnitus. Homeostatic plasticity, the most discussed and acknowledged mechanism in recent years, is most likely responsible for excited central activity following cochlear damage.

Test-retest reliability of the 40 Hz EEG auditory steady-state response.

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Kristina L McFadden

Full Text Available Auditory evoked steady-state responses are increasingly being used as a marker of brain function and dysfunction in various neuropsychiatric disorders, but research investigating the test-retest reliability of this response is lacking. The purpose of this study was to assess the consistency of the auditory steady-state response (ASSR across sessions. Furthermore, the current study aimed to investigate how the reliability of the ASSR is impacted by stimulus parameters and analysis method employed. The consistency of this response across two sessions spaced approximately 1 week apart was measured in nineteen healthy adults using electroencephalography (EEG. The ASSR was entrained by both 40 Hz amplitude-modulated white noise and click train stimuli. Correlations between sessions were assessed with two separate analytical techniques: a channel-level analysis across the whole-head array and b signal-space projection from auditory dipoles. Overall, the ASSR was significantly correlated between sessions 1 and 2 (p<0.05, multiple comparison corrected, suggesting adequate test-retest reliability of this response. The current study also suggests that measures of inter-trial phase coherence may be more reliable between sessions than measures of evoked power. Results were similar between the two analysis methods, but reliability varied depending on the presented stimulus, with click train stimuli producing more consistent responses than white noise stimuli.

Benzodiazepine temazepam suppresses the transient auditory 40-Hz response amplitude in humans.

Science.gov (United States)

Jääskeläinen, I P; Hirvonen, J; Saher, M; Pekkonen, E; Sillanaukee, P; Näätänen, R; Tiitinen, H

1999-06-18

To discern the role of the GABA(A) receptors in the generation and attentive modulation of the transient auditory 40-Hz response, the effects of the benzodiazepine temazepam (10 mg) were studied in 10 healthy social drinkers, using a double-blind placebo-controlled design. Three hundred Hertz standard and 330 Hz rare deviant tones were presented to the left, and 1000 Hz standards and 1100 Hz deviants to the right ear of the subjects. Subjects attended to a designated ear and were to detect deviants therein while ignoring tones to the other. Temazepam significantly suppressed the amplitude of the 40-Hz response, the effect being equal for attended and non-attended tone responses. This suggests involvement of GABA(A) receptors in transient auditory 40-Hz response generation, however, not in the attentive modulation of the 40-Hz response.

DESCRIPTION OF BRAINSTEM AUDITORY EVOKED RESPONSES (AIR AND BONE CONDUCTION IN CHILDREN WITH NORMAL HEARING

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A. V. Pashkov

2014-01-01

Full Text Available Diagnosis of hearing level in small children with conductive hearing loss associated with congenital craniofacial abnormalities, particularly with agenesis of external ear and external auditory meatus is a pressing issue. Conventional methods of assessing hearing in the first years of life, i. e. registration of brainstem auditory evoked responses to acoustic stimuli in the event of air conduction, does not give an indication of the auditory analyzer’s condition due to potential conductive hearing loss in these patients. This study was aimed at assessing potential of diagnosing the auditory analyzer’s function with registering brainstem auditory evoked responses (BAERs to acoustic stimuli transmitted by means of a bone vibrator. The study involved 17 children aged 3–10 years with normal hearing. We compared parameters of registering brainstem auditory evoked responses (peak V depending on the type of stimulus transmission (air/bone in children with normal hearing. The data on thresholds of the BAERs registered to acoustic stimuli in the event of air and bone conduction obtained in this study are comparable; hearing thresholds in the event of acoustic stimulation by means of a bone vibrator correlates with the results of the BAERs registered to the stimuli transmitted by means of air conduction earphones (r = 0.9. High correlation of thresholds of BAERs to the stimuli transmitted by means of a bone vibrator with thresholds of BAERs registered when air conduction earphones were used helps to assess auditory analyzer’s condition in patients with any form of conductive hearing loss.  

Social interaction with a tutor modulates responsiveness of specific auditory neurons in juvenile zebra finches.

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Yanagihara, Shin; Yazaki-Sugiyama, Yoko

2018-04-12

Behavioral states of animals, such as observing the behavior of a conspecific, modify signal perception and/or sensations that influence state-dependent higher cognitive behavior, such as learning. Recent studies have shown that neuronal responsiveness to sensory signals is modified when animals are engaged in social interactions with others or in locomotor activities. However, how these changes produce state-dependent differences in higher cognitive function is still largely unknown. Zebra finches, which have served as the premier songbird model, learn to sing from early auditory experiences with tutors. They also learn from playback of recorded songs however, learning can be greatly improved when song models are provided through social communication with tutors (Eales, 1989; Chen et al., 2016). Recently we found a subset of neurons in the higher-level auditory cortex of juvenile zebra finches that exhibit highly selective auditory responses to the tutor song after song learning, suggesting an auditory memory trace of the tutor song (Yanagihara and Yazaki-Sugiyama, 2016). Here we show that auditory responses of these selective neurons became greater when juveniles were paired with their tutors, while responses of non-selective neurons did not change. These results suggest that social interaction modulates cortical activity and might function in state-dependent song learning. Copyright © 2018 Elsevier B.V. All rights reserved.

Auditory event-related responses to diphthongs in different attention conditions

DEFF Research Database (Denmark)

Morris, David Jackson; Steinmetzger, Kurt; Tøndering, John

2016-01-01

The modulation of auditory event-related potentials (ERP) by attention generally results in larger amplitudes when stimuli are attended. We measured the P1-N1-P2 acoustic change complex elicited with synthetic overt (second formant, F2 = 1000 Hz) and subtle (F2 = 100 Hz) diphthongs, while subjects...... (i) attended to the auditory stimuli, (ii) ignored the auditory stimuli and watched a film, and (iii) diverted their attention to a visual discrimination task. Responses elicited by diphthongs where F2 values rose and fell were found to be different and this precluded their combined analysis....... Multivariate analysis of ERP components from the rising F2 changes showed main effects of attention on P2 amplitude and latency, and N1-P2 amplitude. P2 amplitude decreased by 40% between the attend and ignore conditions, and by 60% between the attend and divert conditions. The effect of diphthong magnitude...

Assessing cross-modal target transition effects with a visual-auditory oddball.

Science.gov (United States)

Kiat, John E

2018-04-30

Prior research has shown contextual manipulations involving temporal and sequence related factors significantly moderate attention-related responses, as indexed by the P3b event-related-potential, towards infrequent (i.e., deviant) target oddball stimuli. However, significantly less research has looked at the influence of cross-modal switching on P3b responding, with the impact of target-to-target cross-modal transitions being virtually unstudied. To address this gap, this study recorded high-density (256 electrodes) EEG data from twenty-five participants as they completed a cross-modal visual-auditory oddball task. This task was comprised of unimodal visual (70% Nontargets: 30% Deviant-targets) and auditory (70% Nontargets: 30% Deviant-targets) oddballs presented in fixed alternating order (i.e., visual-auditory-visual-auditory, etc.) with participants being tasked with detecting deviant-targets in both modalities. Differences in the P3b response towards deviant-targets as a function of preceding deviant-target's presentation modality was analyzed using temporal-spatial PCA decomposition. In line with predictions, the results indicate that the ERP response to auditory deviant-targets preceded by visual deviant-targets exhibits an elevated P3b, relative to the processing of auditory deviant-targets preceded by auditory deviant-targets. However, the processing of visual deviant-targets preceded by auditory deviant-targets exhibited a reduced P3b response, relative to the P3b response towards visual deviant-targets preceded by visual deviant-targets. These findings provide the first demonstration of temporally and perceptually decoupled target-to-target cross-modal transitions moderating P3b responses on the oddball paradigm, generally providing support for the context-updating interpretation of the P3b response. Copyright © 2017. Published by Elsevier B.V.

Task-specific modulation of human auditory evoked responses in a delayed-match-to-sample task

Directory of Open Access Journals (Sweden)

Feng eRong

2011-05-01

Full Text Available In this study, we focus our investigation on task-specific cognitive modulation of early cortical auditory processing in human cerebral cortex. During the experiments, we acquired whole-head magnetoencephalography (MEG data while participants were performing an auditory delayed-match-to-sample (DMS task and associated control tasks. Using a spatial filtering beamformer technique to simultaneously estimate multiple source activities inside the human brain, we observed a significant DMS-specific suppression of the auditory evoked response to the second stimulus in a sound pair, with the center of the effect being located in the vicinity of the left auditory cortex. For the right auditory cortex, a non-invariant suppression effect was observed in both DMS and control tasks. Furthermore, analysis of coherence revealed a beta band (12 ~ 20 Hz DMS-specific enhanced functional interaction between the sources in left auditory cortex and those in left inferior frontal gyrus, which has been shown to involve in short-term memory processing during the delay period of DMS task. Our findings support the view that early evoked cortical responses to incoming acoustic stimuli can be modulated by task-specific cognitive functions by means of frontal-temporal functional interactions.

Speech-evoked auditory brainstem responses in children with hearing loss.

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Koravand, Amineh; Al Osman, Rida; Rivest, Véronique; Poulin, Catherine

2017-08-01

The main objective of the present study was to investigate subcortical auditory processing in children with sensorineural hearing loss. Auditory Brainstem Responses (ABRs) were recorded using click and speech/da/stimuli. Twenty-five children, aged 6-14 years old, participated in the study: 13 with normal hearing acuity and 12 with sensorineural hearing loss. No significant differences were observed for the click-evoked ABRs between normal hearing and hearing-impaired groups. For the speech-evoked ABRs, no significant differences were found for the latencies of the following responses between the two groups: onset (V and A), transition (C), one of the steady-state wave (F), and offset (O). However, the latency of the steady-state waves (D and E) was significantly longer for the hearing-impaired compared to the normal hearing group. Furthermore, the amplitude of the offset wave O and of the envelope frequency response (EFR) of the speech-evoked ABRs was significantly larger for the hearing-impaired compared to the normal hearing group. Results obtained from the speech-evoked ABRs suggest that children with a mild to moderately-severe sensorineural hearing loss have a specific pattern of subcortical auditory processing. Our results show differences for the speech-evoked ABRs in normal hearing children compared to hearing-impaired children. These results add to the body of the literature on how children with hearing loss process speech at the brainstem level. Copyright © 2017 Elsevier B.V. All rights reserved.

MRI enhancement of the facial nerve with Gd-DTPA, 2; Investigation of enhanced nerve portions in patients with facial palsy

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Yanagida, Masahiro (Kansai Medical School, Moriguchi, Osaka (Japan))

1993-08-01

We performed enhanced MRI using Gd-DTPA in 84 patients with facial palsy. After assessing enhancement of the normal facial nerve, we examined enhancement in patients with Bell's palsy and Ramsay Hunt syndrome. In 95% of patients with Bell's palsy, enhancement was obtained in the distal IAC and labyrinthine portions. In 72%, enhancement was significant from the distal IAC portion through the vertical portion. In some of the patients who underwent enhanced MRI twice, increased signal intensity was observed in distal portions such as the vertical portion. In many cases of Ramsay Hunt syndrome, enhancement was seen extensively in the IAC portion through the vertical portion. In the subjects with internal auditory symptoms such as vertigo and tinnitus, enhancement of the IAC portion was seen not only in the facial nerve but also in the vestibular and the cochlear nerves. These results suggest that the vascular permeability of lesions in Bell's palsy may be increased from the distal IAC portion to the vertical portion. Judging from the present findings with Ramsay Hunt syndrome, symptoms related to the enhanced portions suggest that accompanying internal auditory symptoms occur due to inflammation of the IAC portions of cochlear and vestibular nerves. (author).

Attentional modulation of auditory steady-state responses.

Science.gov (United States)

Mahajan, Yatin; Davis, Chris; Kim, Jeesun

2014-01-01

Auditory selective attention enables task-relevant auditory events to be enhanced and irrelevant ones suppressed. In the present study we used a frequency tagging paradigm to investigate the effects of attention on auditory steady state responses (ASSR). The ASSR was elicited by simultaneously presenting two different streams of white noise, amplitude modulated at either 16 and 23.5 Hz or 32.5 and 40 Hz. The two different frequencies were presented to each ear and participants were instructed to selectively attend to one ear or the other (confirmed by behavioral evidence). The results revealed that modulation of ASSR by selective attention depended on the modulation frequencies used and whether the activation was contralateral or ipsilateral. Attention enhanced the ASSR for contralateral activation from either ear for 16 Hz and suppressed the ASSR for ipsilateral activation for 16 Hz and 23.5 Hz. For modulation frequencies of 32.5 or 40 Hz attention did not affect the ASSR. We propose that the pattern of enhancement and inhibition may be due to binaural suppressive effects on ipsilateral stimulation and the dominance of contralateral hemisphere during dichotic listening. In addition to the influence of cortical processing asymmetries, these results may also reflect a bias towards inhibitory ipsilateral and excitatory contralateral activation present at the level of inferior colliculus. That the effect of attention was clearest for the lower modulation frequencies suggests that such effects are likely mediated by cortical brain structures or by those in close proximity to cortex.

Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

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J. Tillein

2012-01-01

Full Text Available To compare the development of the auditory system in hearing and completely acoustically deprived animals, naive congenitally deaf white cats (CDCs and hearing controls (HCs were investigated at different developmental stages from birth till adulthood. The CDCs had no hearing experience before the acute experiment. In both groups of animals, responses to cochlear implant stimulation were acutely assessed. Electrically evoked auditory brainstem responses (E-ABRs were recorded with monopolar stimulation at different current levels. CDCs demonstrated extensive development of E-ABRs, from first signs of responses at postnatal (p.n. day 3 through appearance of all waves of brainstem response at day 8 p.n. to mature responses around day 90 p.n.. Wave I of E-ABRs could not be distinguished from the artifact in majority of CDCs, whereas in HCs, it was clearly separated from the stimulus artifact. Waves II, III, and IV demonstrated higher thresholds in CDCs, whereas this difference was not found for wave V. Amplitudes of wave III were significantly higher in HCs, whereas wave V amplitudes were significantly higher in CDCs. No differences in latencies were observed between the animal groups. These data demonstrate significant postnatal subcortical development in absence of hearing, and also divergent effects of deafness on early waves II–IV and wave V of the E-ABR.

Auditory steady-state responses in cochlear implant users: Effect of modulation frequency and stimulation artifacts.

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Gransier, Robin; Deprez, Hanne; Hofmann, Michael; Moonen, Marc; van Wieringen, Astrid; Wouters, Jan

2016-05-01

Previous studies have shown that objective measures based on stimulation with low-rate pulse trains fail to predict the threshold levels of cochlear implant (CI) users for high-rate pulse trains, as used in clinical devices. Electrically evoked auditory steady-state responses (EASSRs) can be elicited by modulated high-rate pulse trains, and can potentially be used to objectively determine threshold levels of CI users. The responsiveness of the auditory pathway of profoundly hearing-impaired CI users to modulation frequencies is, however, not known. In the present study we investigated the responsiveness of the auditory pathway of CI users to a monopolar 500 pulses per second (pps) pulse train modulated between 1 and 100 Hz. EASSRs to forty-three modulation frequencies, elicited at the subject's maximum comfort level, were recorded by means of electroencephalography. Stimulation artifacts were removed by a linear interpolation between a pre- and post-stimulus sample (i.e., blanking). The phase delay across modulation frequencies was used to differentiate between the neural response and a possible residual stimulation artifact after blanking. Stimulation artifacts were longer than the inter-pulse interval of the 500pps pulse train for recording electrodes ipsilateral to the CI. As a result the stimulation artifacts could not be removed by artifact removal on the bases of linear interpolation for recording electrodes ipsilateral to the CI. However, artifact-free responses could be obtained in all subjects from recording electrodes contralateral to the CI, when subject specific reference electrodes (Cz or Fpz) were used. EASSRs to modulation frequencies within the 30-50 Hz range resulted in significant responses in all subjects. Only a small number of significant responses could be obtained, during a measurement period of 5 min, that originate from the brain stem (i.e., modulation frequencies in the 80-100 Hz range). This reduced synchronized activity of brain stem

Attention-related modulation of auditory brainstem responses during contralateral noise exposure.

Science.gov (United States)

Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

2008-10-29

As determinants facilitating attention-related modulation of the auditory brainstem response (ABR), two experimental factors were examined: (i) auditory discrimination; and (ii) contralateral masking intensity. Tone pips at 80 dB sound pressure level were presented to the left ear via either single-tone exposures or oddball exposures, whereas white noise was delivered continuously to the right ear at variable intensities (none--80 dB sound pressure level). Participants each conducted two tasks during stimulation, either reading a book (ignoring task) or detecting target tones (attentive task). Task-related modulation within the ABR range was found only during oddball exposures at contralateral masking intensities greater than or equal to 60 dB. Attention-related modulation of ABR can thus be detected reliably during auditory discrimination under contralateral masking of sufficient intensity.

Concentrated pitch discrimination modulates auditory brainstem responses during contralateral noise exposure.

Science.gov (United States)

Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

2010-03-31

This study examined a notion that auditory discrimination is a requisite for attention-related modulation of the auditory brainstem response (ABR) during contralateral noise exposure. Given that the right ear was exposed continuously with white noise at an intensity of 60-80 dB sound pressure level, tone pips at 80 dB sound pressure level were delivered to the left ear through either single-stimulus or oddball procedures. Participants conducted reading (ignoring task) and counting target tones (attentive task) during stimulation. The oddball but not the single-stimulus procedures elicited task-related modulations in both early (ABR) and late (processing negativity) event-related potentials simultaneously. The elicitation of the attention-related ABR modulation during contralateral noise exposure is thus considered to require auditory discrimination and have the corticofugal nature evidently.

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

OpenAIRE

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

2013-01-01

A differential response to sound frequency is a fundamental property of auditory neurons. Frequency analysis in the cochlea gives rise to V-shaped tuning functions in auditory nerve fibres, but by the level of the inferior colliculus (IC), the midbrain nucleus of the auditory pathway, neuronal receptive fields display diverse shapes that reflect the interplay of excitation and inhibition. The origin and nature of these frequency receptive field types is still open to question. One proposed hy...

Prepulse Inhibition of Auditory Cortical Responses in the Caudolateral Superior Temporal Gyrus in Macaca mulatta.

Science.gov (United States)

Chen, Zuyue; Parkkonen, Lauri; Wei, Jingkuan; Dong, Jin-Run; Ma, Yuanye; Carlson, Synnöve

2018-04-01

Prepulse inhibition (PPI) refers to a decreased response to a startling stimulus when another weaker stimulus precedes it. Most PPI studies have focused on the physiological startle reflex and fewer have reported the PPI of cortical responses. We recorded local field potentials (LFPs) in four monkeys and investigated whether the PPI of auditory cortical responses (alpha, beta, and gamma oscillations and evoked potentials) can be demonstrated in the caudolateral belt of the superior temporal gyrus (STGcb). We also investigated whether the presence of a conspecific, which draws attention away from the auditory stimuli, affects the PPI of auditory cortical responses. The PPI paradigm consisted of Pulse-only and Prepulse + Pulse trials that were presented randomly while the monkey was alone (ALONE) and while another monkey was present in the same room (ACCOMP). The LFPs to the Pulse were significantly suppressed by the Prepulse thus, demonstrating PPI of cortical responses in the STGcb. The PPI-related inhibition of the N1 amplitude of the evoked responses and cortical oscillations to the Pulse were not affected by the presence of a conspecific. In contrast, gamma oscillations and the amplitude of the N1 response to Pulse-only were suppressed in the ACCOMP condition compared to the ALONE condition. These findings demonstrate PPI in the monkey STGcb and suggest that the PPI of auditory cortical responses in the monkey STGcb is a pre-attentive inhibitory process that is independent of attentional modulation.

Selective attention modulates human auditory brainstem responses: relative contributions of frequency and spatial cues.

Directory of Open Access Journals (Sweden)

Alexandre Lehmann

Full Text Available Selective attention is the mechanism that allows focusing one's attention on a particular stimulus while filtering out a range of other stimuli, for instance, on a single conversation in a noisy room. Attending to one sound source rather than another changes activity in the human auditory cortex, but it is unclear whether attention to different acoustic features, such as voice pitch and speaker location, modulates subcortical activity. Studies using a dichotic listening paradigm indicated that auditory brainstem processing may be modulated by the direction of attention. We investigated whether endogenous selective attention to one of two speech signals affects amplitude and phase locking in auditory brainstem responses when the signals were either discriminable by frequency content alone, or by frequency content and spatial location. Frequency-following responses to the speech sounds were significantly modulated in both conditions. The modulation was specific to the task-relevant frequency band. The effect was stronger when both frequency and spatial information were available. Patterns of response were variable between participants, and were correlated with psychophysical discriminability of the stimuli, suggesting that the modulation was biologically relevant. Our results demonstrate that auditory brainstem responses are susceptible to efferent modulation related to behavioral goals. Furthermore they suggest that mechanisms of selective attention actively shape activity at early subcortical processing stages according to task relevance and based on frequency and spatial cues.

Auditory evoked responses to binaural beat illusion: stimulus generation and the derivation of the Binaural Interaction Component (BIC).

Science.gov (United States)

Ozdamar, Ozcan; Bohorquez, Jorge; Mihajloski, Todor; Yavuz, Erdem; Lachowska, Magdalena

2011-01-01

Electrophysiological indices of auditory binaural beats illusions are studied using late latency evoked responses. Binaural beats are generated by continuous monaural FM tones with slightly different ascending and descending frequencies lasting about 25 ms presented at 1 sec intervals. Frequency changes are carefully adjusted to avoid any creation of abrupt waveform changes. Binaural Interaction Component (BIC) analysis is used to separate the neural responses due to binaural involvement. The results show that the transient auditory evoked responses can be obtained from the auditory illusion of binaural beats.

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

Science.gov (United States)

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

TRPM8 mechanism of autonomic nerve response to cold in respiratory airway

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Wang Cong-Yi

2008-06-01

Full Text Available Abstract Breathing cold air without proper temperature exchange can induce strong respiratory autonomic responses including cough, airway constriction and mucosal secretion, and can exacerbate existing asthma conditions and even directly trigger an asthma attack. Vagal afferent fiber is thought to be involved in the cold-induced respiratory responses through autonomic nerve reflex. However, molecular mechanisms by which vagal afferent fibers are excited by cold remain unknown. Using retrograde labeling, immunostaining, calcium imaging, and electrophysiological recordings, here we show that a subpopulation of airway vagal afferent nerves express TRPM8 receptors and that activation of TRPM8 receptors by cold excites these airway autonomic nerves. Thus activation of TRPM8 receptors may provoke autonomic nerve reflex to increase airway resistance. This putative autonomic response may be associated with cold-induced exacerbation of asthma and other pulmonary disorders, making TRPM8 receptors a possible target for prevention of cold-associated respiratory disorders.

Long-term evolution of brainstem electrical evoked responses to sound after restricted ablation of the auditory cortex.

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Verónica Lamas

Full Text Available INTRODUCTION: This study aimed to assess the top-down control of sound processing in the auditory brainstem of rats. Short latency evoked responses were analyzed after unilateral or bilateral ablation of auditory cortex. This experimental paradigm was also used towards analyzing the long-term evolution of post-lesion plasticity in the auditory system and its ability to self-repair. METHOD: Auditory cortex lesions were performed in rats by stereotactically guided fine-needle aspiration of the cerebrocortical surface. Auditory Brainstem Responses (ABR were recorded at post-surgery day (PSD 1, 7, 15 and 30. Recordings were performed under closed-field conditions, using click trains at different sound intensity levels, followed by statistical analysis of threshold values and ABR amplitude and latency variables. Subsequently, brains were sectioned and immunostained for GAD and parvalbumin to assess the location and extent of lesions accurately. RESULTS: Alterations in ABR variables depended on the type of lesion and post-surgery time of ABR recordings. Accordingly, bilateral ablations caused a statistically significant increase in thresholds at PSD1 and 7 and a decrease in waves amplitudes at PSD1 that recover at PSD7. No effects on latency were noted at PSD1 and 7, whilst recordings at PSD15 and 30 showed statistically significant decreases in latency. Conversely, unilateral ablations had no effect on auditory thresholds or latencies, while wave amplitudes only decreased at PSD1 strictly in the ipsilateral ear. CONCLUSION: Post-lesion plasticity in the auditory system acts in two time periods: short-term period of decreased sound sensitivity (until PSD7, most likely resulting from axonal degeneration; and a long-term period (up to PSD7, with changes in latency responses and recovery of thresholds and amplitudes values. The cerebral cortex may have a net positive gain on the auditory pathway response to sound.

Attentional Modulation of Auditory Steady-State Responses

Science.gov (United States)

Mahajan, Yatin; Davis, Chris; Kim, Jeesun

2014-01-01

Auditory selective attention enables task-relevant auditory events to be enhanced and irrelevant ones suppressed. In the present study we used a frequency tagging paradigm to investigate the effects of attention on auditory steady state responses (ASSR). The ASSR was elicited by simultaneously presenting two different streams of white noise, amplitude modulated at either 16 and 23.5 Hz or 32.5 and 40 Hz. The two different frequencies were presented to each ear and participants were instructed to selectively attend to one ear or the other (confirmed by behavioral evidence). The results revealed that modulation of ASSR by selective attention depended on the modulation frequencies used and whether the activation was contralateral or ipsilateral. Attention enhanced the ASSR for contralateral activation from either ear for 16 Hz and suppressed the ASSR for ipsilateral activation for 16 Hz and 23.5 Hz. For modulation frequencies of 32.5 or 40 Hz attention did not affect the ASSR. We propose that the pattern of enhancement and inhibition may be due to binaural suppressive effects on ipsilateral stimulation and the dominance of contralateral hemisphere during dichotic listening. In addition to the influence of cortical processing asymmetries, these results may also reflect a bias towards inhibitory ipsilateral and excitatory contralateral activation present at the level of inferior colliculus. That the effect of attention was clearest for the lower modulation frequencies suggests that such effects are likely mediated by cortical brain structures or by those in close proximity to cortex. PMID:25334021

Attentional modulation of auditory steady-state responses.

Directory of Open Access Journals (Sweden)

Yatin Mahajan

Full Text Available Auditory selective attention enables task-relevant auditory events to be enhanced and irrelevant ones suppressed. In the present study we used a frequency tagging paradigm to investigate the effects of attention on auditory steady state responses (ASSR. The ASSR was elicited by simultaneously presenting two different streams of white noise, amplitude modulated at either 16 and 23.5 Hz or 32.5 and 40 Hz. The two different frequencies were presented to each ear and participants were instructed to selectively attend to one ear or the other (confirmed by behavioral evidence. The results revealed that modulation of ASSR by selective attention depended on the modulation frequencies used and whether the activation was contralateral or ipsilateral. Attention enhanced the ASSR for contralateral activation from either ear for 16 Hz and suppressed the ASSR for ipsilateral activation for 16 Hz and 23.5 Hz. For modulation frequencies of 32.5 or 40 Hz attention did not affect the ASSR. We propose that the pattern of enhancement and inhibition may be due to binaural suppressive effects on ipsilateral stimulation and the dominance of contralateral hemisphere during dichotic listening. In addition to the influence of cortical processing asymmetries, these results may also reflect a bias towards inhibitory ipsilateral and excitatory contralateral activation present at the level of inferior colliculus. That the effect of attention was clearest for the lower modulation frequencies suggests that such effects are likely mediated by cortical brain structures or by those in close proximity to cortex.

Working Memory and Auditory Imagery Predict Sensorimotor Synchronization with Expressively Timed Music.

Science.gov (United States)

Colley, Ian D; Keller, Peter E; Halpern, Andrea R

2017-08-11

Sensorimotor synchronization (SMS) is prevalent and readily studied in musical settings, as most people are able to perceive and synchronize with a beat (e.g. by finger tapping). We took an individual differences approach to understanding SMS to real music characterized by expressive timing (i.e. fluctuating beat regularity). Given the dynamic nature of SMS, we hypothesized that individual differences in working memory and auditory imagery-both fluid cognitive processes-would predict SMS at two levels: 1) mean absolute asynchrony (a measure of synchronization error), and 2) anticipatory timing (i.e. predicting, rather than reacting to beat intervals). In Experiment 1, participants completed two working memory tasks, four auditory imagery tasks, and an SMS-tapping task. Hierarchical regression models were used to predict SMS performance, with results showing dissociations among imagery types in relation to mean absolute asynchrony, and evidence of a role for working memory in anticipatory timing. In Experiment 2, a new sample of participants completed an expressive timing perception task to examine the role of imagery in perception without action. Results suggest that imagery vividness is important for perceiving and control is important for synchronizing with, irregular but ecologically valid musical time series. Working memory is implicated in synchronizing by anticipating events in the series.

Synchrony of auditory brain responses predicts behavioral ability to keep still in children with autism spectrum disorder

Directory of Open Access Journals (Sweden)

Yuko Yoshimura

2016-01-01

Full Text Available The auditory-evoked P1m, recorded by magnetoencephalography, reflects a central auditory processing ability in human children. One recent study revealed that asynchrony of P1m between the right and left hemispheres reflected a central auditory processing disorder (i.e., attention deficit hyperactivity disorder, ADHD in children. However, to date, the relationship between auditory P1m right-left hemispheric synchronization and the comorbidity of hyperactivity in children with autism spectrum disorder (ASD is unknown. In this study, based on a previous report of an asynchrony of P1m in children with ADHD, to clarify whether the P1m right-left hemispheric synchronization is related to the symptom of hyperactivity in children with ASD, we investigated the relationship between voice-evoked P1m right-left hemispheric synchronization and hyperactivity in children with ASD. In addition to synchronization, we investigated the right-left hemispheric lateralization. Our findings failed to demonstrate significant differences in these values between ASD children with and without the symptom of hyperactivity, which was evaluated using the Autism Diagnostic Observational Schedule, Generic (ADOS-G subscale. However, there was a significant correlation between the degrees of hemispheric synchronization and the ability to keep still during 12-minute MEG recording periods. Our results also suggested that asynchrony in the bilateral brain auditory processing system is associated with ADHD-like symptoms in children with ASD.

MRI enhancement of the facial nerve with Gd-DTPA, 2

International Nuclear Information System (INIS)

Yanagida, Masahiro

1993-01-01

We performed enhanced MRI using Gd-DTPA in 84 patients with facial palsy. After assessing enhancement of the normal facial nerve, we examined enhancement in patients with Bell's palsy and Ramsay Hunt syndrome. In 95% of patients with Bell's palsy, enhancement was obtained in the distal IAC and labyrinthine portions. In 72%, enhancement was significant from the distal IAC portion through the vertical portion. In some of the patients who underwent enhanced MRI twice, increased signal intensity was observed in distal portions such as the vertical portion. In many cases of Ramsay Hunt syndrome, enhancement was seen extensively in the IAC portion through the vertical portion. In the subjects with internal auditory symptoms such as vertigo and tinnitus, enhancement of the IAC portion was seen not only in the facial nerve but also in the vestibular and the cochlear nerves. These results suggest that the vascular permeability of lesions in Bell's palsy may be increased from the distal IAC portion to the vertical portion. Judging from the present findings with Ramsay Hunt syndrome, symptoms related to the enhanced portions suggest that accompanying internal auditory symptoms occur due to inflammation of the IAC portions of cochlear and vestibular nerves. (author)

Integration of auditory and visual speech information

NARCIS (Netherlands)

Hall, M.; Smeele, P.M.T.; Kuhl, P.K.

1998-01-01

The integration of auditory and visual speech is observed when modes specify different places of articulation. Influences of auditory variation on integration were examined using consonant identifi-cation, plus quality and similarity ratings. Auditory identification predicted auditory-visual

An Improved Dissonance Measure Based on Auditory Memory

DEFF Research Database (Denmark)

Jensen, Kristoffer; Hjortkjær, Jens

2012-01-01

Dissonance is an important feature in music audio analysis. We present here a dissonance model that accounts for the temporal integration of dissonant events in auditory short term memory. We compare the memory-based dissonance extracted from musical audio sequences to the response of human...... listeners. In a number of tests, the memory model predicts listener’s response better than traditional dissonance measures....

Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

OpenAIRE

Renata Mota Mamede de Carvallo; Carla Gentile Matas; Isabela de Souza Jardim

2008-01-01

Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU), as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem...

Neurovascular compression syndrome of the eighth cranial nerve

International Nuclear Information System (INIS)

Itoh, Akinori

2010-01-01

Neurovascular compression syndrome (NVCS) involves neuropathy due to intracranial blood vessels compressing the cranial nerves. NVCS of the eighth cranial nerve is less reportedly established as a clinical entity than that of the fifth and seventh cranial nerves. We report 17 cases of NVCS of the eighth cranial nerve and their clinical features. Clinical symptoms and test findings among our subjects indicated that most were aged more than 65 years, were unilateral, had intermittent tinnitus, suffered attacks lasting a few seconds dozens of times a day, experienced dizziness concomitantly with tinnitus, aggravated tinnitus and dizziness when tilting the head toward the affected side and looking downward (positional tinnitus, positional dizziness), heard specific tinnitus sounds such as crackling differing from those in cochlear tinnitus, had mild or no hearing loss, were diagnosed with retrocochlear hearing disturbance due to an interpeak latency delay between waves I and III of the auditory brainstem response (ABR), often had no nystagmus or canal paresis (CP), were found in constructive interference steady state magnetic resonance imaging (CISS MRI) to have compression of the eighth cranial nerve by the vertebral artery (VA) or the anterior inferior cerebellar artery (AICA), rarely had concomitant facial spasms, and had tinnitus and dizziness markedly suppressed by carbamazepine. With the number of elderly individuals continuing to increase, cases of NVCS due to arteriosclerotic changes in cerebral blood vessels are expected to increase, making it necessary to consider NVCS in elderly subjects with dizziness, tinnitus, and hearing loss. (author)

Neurovascular compression syndrome of the eighth cranial nerve

Energy Technology Data Exchange (ETDEWEB)

Itoh, Akinori [Saitama Medical Univ., Faculty of Medicine, Moroyama, Saitama (Japan)

2010-04-15

Neurovascular compression syndrome (NVCS) involves neuropathy due to intracranial blood vessels compressing the cranial nerves. NVCS of the eighth cranial nerve is less reportedly established as a clinical entity than that of the fifth and seventh cranial nerves. We report 17 cases of NVCS of the eighth cranial nerve and their clinical features. Clinical symptoms and test findings among our subjects indicated that most were aged more than 65 years, were unilateral, had intermittent tinnitus, suffered attacks lasting a few seconds dozens of times a day, experienced dizziness concomitantly with tinnitus, aggravated tinnitus and dizziness when tilting the head toward the affected side and looking downward (positional tinnitus, positional dizziness), heard specific tinnitus sounds such as crackling differing from those in cochlear tinnitus, had mild or no hearing loss, were diagnosed with retrocochlear hearing disturbance due to an interpeak latency delay between waves I and III of the auditory brainstem response (ABR), often had no nystagmus or canal paresis (CP), were found in constructive interference steady state magnetic resonance imaging (CISS MRI) to have compression of the eighth cranial nerve by the vertebral artery (VA) or the anterior inferior cerebellar artery (AICA), rarely had concomitant facial spasms, and had tinnitus and dizziness markedly suppressed by carbamazepine. With the number of elderly individuals continuing to increase, cases of NVCS due to arteriosclerotic changes in cerebral blood vessels are expected to increase, making it necessary to consider NVCS in elderly subjects with dizziness, tinnitus, and hearing loss. (author)

Brain stem auditory evoked responses in chronic alcoholics.

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Chan, Y W; McLeod, J G; Tuck, R R; Feary, P A

1985-01-01

Brain stem auditory evoked responses (BAERs) were performed on 25 alcoholic patients with Wernicke-Korsakoff syndrome, 56 alcoholic patients without Wernicke-Korsakoff syndrome, 24 of whom had cerebellar ataxia, and 37 control subjects. Abnormal BAERs were found in 48% of patients with Wernicke-Korsakoff syndrome, in 25% of alcoholic patients without Wernicke-Korsakoff syndrome but with cerebellar ataxia, and in 13% of alcoholic patients without Wernicke-Korsakoff syndrome or ataxia. The mean...

Electrophysiological assessment of auditory processing disorder in children with non-syndromic cleft lip and/or palate.

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Ma, Xiaoran; McPherson, Bradley; Ma, Lian

2016-01-01

Cleft lip and/or palate is a common congenital craniofacial malformation found worldwide. A frequently associated disorder is conductive hearing loss, and this disorder has been thoroughly investigated in children with non-syndromic cleft lip and/or palate (NSCL/P). However, analysis of auditory processing function is rarely reported for this population, although this issue should not be ignored since abnormal auditory cortical structures have been found in populations with cleft disorders. The present study utilized electrophysiological tests to assess the auditory status of a large group of children with NSCL/P, and investigated whether this group had less robust central auditory processing abilities compared to craniofacially normal children. 146 children with NSCL/P who had normal peripheral hearing thresholds, and 60 craniofacially normal children aged from 6 to 15 years, were recruited. Electrophysiological tests, including auditory brainstem response (ABR), P1-N1-P2 complex, and P300 component recording, were conducted. ABR and N1 wave latencies were significantly prolonged in children with NSCL/P. An atypical developmental trend was found for long latency potentials in children with cleft compared to control group children. Children with unilateral cleft lip and palate showed a greater level of abnormal results compared with other cleft subgroups, whereas the cleft lip subgroup had the most robust responses for all tests. Children with NSCL/P may have slower than normal neural transmission times between the peripheral auditory nerve and brainstem. Possible delayed development of myelination and synaptogenesis may also influence auditory processing function in this population. Present research outcomes were consistent with previous, smaller sample size, electrophysiological studies on infants and children with cleft lip/palate disorders. In view of the these findings, and reports of educational disadvantage associated with cleft disorders, further research

How do auditory cortex neurons represent communication sounds?

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Gaucher, Quentin; Huetz, Chloé; Gourévitch, Boris; Laudanski, Jonathan; Occelli, Florian; Edeline, Jean-Marc

2013-11-01

A major goal in auditory neuroscience is to characterize how communication sounds are represented at the cortical level. The present review aims at investigating the role of auditory cortex in the processing of speech, bird songs and other vocalizations, which all are spectrally and temporally highly structured sounds. Whereas earlier studies have simply looked for neurons exhibiting higher firing rates to particular conspecific vocalizations over their modified, artificially synthesized versions, more recent studies determined the coding capacity of temporal spike patterns, which are prominent in primary and non-primary areas (and also in non-auditory cortical areas). In several cases, this information seems to be correlated with the behavioral performance of human or animal subjects, suggesting that spike-timing based coding strategies might set the foundations of our perceptive abilities. Also, it is now clear that the responses of auditory cortex neurons are highly nonlinear and that their responses to natural stimuli cannot be predicted from their responses to artificial stimuli such as moving ripples and broadband noises. Since auditory cortex neurons cannot follow rapid fluctuations of the vocalizations envelope, they only respond at specific time points during communication sounds, which can serve as temporal markers for integrating the temporal and spectral processing taking place at subcortical relays. Thus, the temporal sparse code of auditory cortex neurons can be considered as a first step for generating high level representations of communication sounds independent of the acoustic characteristic of these sounds. This article is part of a Special Issue entitled "Communication Sounds and the Brain: New Directions and Perspectives". Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of cochlear nerve electrocautery on the adult cochlear nucleus.

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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.

Auditory steady state responses and cochlear implants: Modeling the artifact-response mixture in the perspective of denoising.

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Mina, Faten; Attina, Virginie; Duroc, Yvan; Veuillet, Evelyne; Truy, Eric; Thai-Van, Hung

2017-01-01

Auditory steady state responses (ASSRs) in cochlear implant (CI) patients are contaminated by the spread of a continuous CI electrical stimulation artifact. The aim of this work was to model the electrophysiological mixture of the CI artifact and the corresponding evoked potentials on scalp electrodes in order to evaluate the performance of denoising algorithms in eliminating the CI artifact in a controlled environment. The basis of the proposed computational framework is a neural mass model representing the nodes of the auditory pathways. Six main contributors to auditory evoked potentials from the cochlear level and up to the auditory cortex were taken into consideration. The simulated dynamics were then projected into a 3-layer realistic head model. 32-channel scalp recordings of the CI artifact-response were then generated by solving the electromagnetic forward problem. As an application, the framework's simulated 32-channel datasets were used to compare the performance of 4 commonly used Independent Component Analysis (ICA) algorithms: infomax, extended infomax, jade and fastICA in eliminating the CI artifact. As expected, two major components were detectable in the simulated datasets, a low frequency component at the modulation frequency and a pulsatile high frequency component related to the stimulation frequency. The first can be attributed to the phase-locked ASSR and the second to the stimulation artifact. Among the ICA algorithms tested, simulations showed that infomax was the most efficient and reliable in denoising the CI artifact-response mixture. Denoising algorithms can induce undesirable deformation of the signal of interest in real CI patient recordings. The proposed framework is a valuable tool for evaluating these algorithms in a controllable environment ahead of experimental or clinical applications.

Auditory steady state responses and cochlear implants: Modeling the artifact-response mixture in the perspective of denoising.

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Faten Mina

Full Text Available Auditory steady state responses (ASSRs in cochlear implant (CI patients are contaminated by the spread of a continuous CI electrical stimulation artifact. The aim of this work was to model the electrophysiological mixture of the CI artifact and the corresponding evoked potentials on scalp electrodes in order to evaluate the performance of denoising algorithms in eliminating the CI artifact in a controlled environment. The basis of the proposed computational framework is a neural mass model representing the nodes of the auditory pathways. Six main contributors to auditory evoked potentials from the cochlear level and up to the auditory cortex were taken into consideration. The simulated dynamics were then projected into a 3-layer realistic head model. 32-channel scalp recordings of the CI artifact-response were then generated by solving the electromagnetic forward problem. As an application, the framework's simulated 32-channel datasets were used to compare the performance of 4 commonly used Independent Component Analysis (ICA algorithms: infomax, extended infomax, jade and fastICA in eliminating the CI artifact. As expected, two major components were detectable in the simulated datasets, a low frequency component at the modulation frequency and a pulsatile high frequency component related to the stimulation frequency. The first can be attributed to the phase-locked ASSR and the second to the stimulation artifact. Among the ICA algorithms tested, simulations showed that infomax was the most efficient and reliable in denoising the CI artifact-response mixture. Denoising algorithms can induce undesirable deformation of the signal of interest in real CI patient recordings. The proposed framework is a valuable tool for evaluating these algorithms in a controllable environment ahead of experimental or clinical applications.

The human auditory brainstem response to running speech reveals a subcortical mechanism for selective attention.

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Forte, Antonio Elia; Etard, Octave; Reichenbach, Tobias

2017-10-10

Humans excel at selectively listening to a target speaker in background noise such as competing voices. While the encoding of speech in the auditory cortex is modulated by selective attention, it remains debated whether such modulation occurs already in subcortical auditory structures. Investigating the contribution of the human brainstem to attention has, in particular, been hindered by the tiny amplitude of the brainstem response. Its measurement normally requires a large number of repetitions of the same short sound stimuli, which may lead to a loss of attention and to neural adaptation. Here we develop a mathematical method to measure the auditory brainstem response to running speech, an acoustic stimulus that does not repeat and that has a high ecological validity. We employ this method to assess the brainstem's activity when a subject listens to one of two competing speakers, and show that the brainstem response is consistently modulated by attention.

Top-down modulation of the auditory steady-state response in a task-switch paradigm

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Nadia Müller

2009-02-01

Full Text Available Auditory selective attention is an important mechanism for top-down selection of the vast amount of auditory information our perceptual system is exposed to. In the present study, the impact of attention on auditory steady-state responses - previously shown to be generated in primary auditory regions - was investigated. This issue is still a matter of debate and recent findings point to a complex pattern of attentional effects on the aSSR. The present study aimed at shedding light on the involvement of ipsilateral and contralateral activations to the attended sound taking into account hemispheric differences and a possible dependency on modulation frequency. In aid of this, a dichotic listening experiment was designed using amplitude-modulated tones that were presented to the left and right ear simultaneously. Participants had to detect target tones in a cued ear while their brain activity was assessed using MEG. Thereby, a modulation of the aSSR by attention could be revealed, interestingly restricted to the left hemisphere and 20 Hz responses: Contralateral activations were enhanced while ipsilateral activations turned out to be reduced. Thus, our findings support and extend recent findings, showing that auditory attention can influence the aSSR, but only under specific circumstances and in a complex pattern regarding the different effects for ipsilateral and contralateral activations.

High-resolution MRI predicts steroid injection response in carpal tunnel syndrome patients

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Aoki, Takatoshi; Oki, Hodaka; Kinoshita, Shunsuke; Yamashita, Yoshiko; Takahashi, Hiroyuki; Hayashida, Yoshiko; Korogi, Yukunori [University of Occupational and Environmental Health School of Medicine, Department of Radiology, Kitakyushu (Japan); Oshige, Takahisa; Sakai, Akinori [University of Occupational and Environmental Health School of Medicine, Department of Orthopaedic Surgery, Kitakyushu (Japan); Matsuyama, Atsushi; Hisaoka, Masanori [University of Occupational and Environmental Health School of Medicine, Department of Pathology and Oncology, Kitakyushu (Japan)

2014-03-15

To correlate median nerve T2 signal and shape at the carpal tunnel with steroid injection (SI) response in carpal tunnel syndrome (CTS) patients. One hundred and sixty-three CTS wrists of 92 consecutive patients who were scheduled to undergo SI were prospectively evaluated with 3-T magnetic resonance imaging (MRI) and a nerve conduction study. All patients underwent axial high-resolution T2-weighted MRI (in-plane resolution of 0.25 x 0.25 mm). The CTS wrists were classified into three groups according to the nerve T2 signal and the flattening ratio at the hook of hamate level: group 1, high and oval; group 2, high and flat; group 3, low and flat. Clinical response to SI was evaluated at 6 months after injection. One hundred and thirteen of the 163 wrists (69.3 %) responded well to SI. The percentage of improvement was 81.7 % (49/60) in group 1, 69.9 % (51/73) in group 2, and 43.3 % (13/30) in group 3 (P < 0.01). On stepwise logistic regression analysis high-resolution MRI was the only significant independent factor for SI response in CTS patients (P < 0.01). High-resolution MRI correlates well with SI response in CTS patients and seems useful for predicting SI response. (orig.)

Neurofeedback-Based Enhancement of Single-Trial Auditory Evoked Potentials: Treatment of Auditory Verbal Hallucinations in Schizophrenia.

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Rieger, Kathryn; Rarra, Marie-Helene; Diaz Hernandez, Laura; Hubl, Daniela; Koenig, Thomas

2018-03-01

Auditory verbal hallucinations depend on a broad neurobiological network ranging from the auditory system to language as well as memory-related processes. As part of this, the auditory N100 event-related potential (ERP) component is attenuated in patients with schizophrenia, with stronger attenuation occurring during auditory verbal hallucinations. Changes in the N100 component assumingly reflect disturbed responsiveness of the auditory system toward external stimuli in schizophrenia. With this premise, we investigated the therapeutic utility of neurofeedback training to modulate the auditory-evoked N100 component in patients with schizophrenia and associated auditory verbal hallucinations. Ten patients completed electroencephalography neurofeedback training for modulation of N100 (treatment condition) or another unrelated component, P200 (control condition). On a behavioral level, only the control group showed a tendency for symptom improvement in the Positive and Negative Syndrome Scale total score in a pre-/postcomparison ( t (4) = 2.71, P = .054); however, no significant differences were found in specific hallucination related symptoms ( t (7) = -0.53, P = .62). There was no significant overall effect of neurofeedback training on ERP components in our paradigm; however, we were able to identify different learning patterns, and found a correlation between learning and improvement in auditory verbal hallucination symptoms across training sessions ( r = 0.664, n = 9, P = .05). This effect results, with cautious interpretation due to the small sample size, primarily from the treatment group ( r = 0.97, n = 4, P = .03). In particular, a within-session learning parameter showed utility for predicting symptom improvement with neurofeedback training. In conclusion, patients with schizophrenia and associated auditory verbal hallucinations who exhibit a learning pattern more characterized by within-session aptitude may benefit from electroencephalography neurofeedback

Auditory-Cortex Short-Term Plasticity Induced by Selective Attention

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Jääskeläinen, Iiro P.; Ahveninen, Jyrki

2014-01-01

The ability to concentrate on relevant sounds in the acoustic environment is crucial for everyday function and communication. Converging lines of evidence suggests that transient functional changes in auditory-cortex neurons, “short-term plasticity”, might explain this fundamental function. Under conditions of strongly focused attention, enhanced processing of attended sounds can take place at very early latencies (~50 ms from sound onset) in primary auditory cortex and possibly even at earlier latencies in subcortical structures. More robust selective-attention short-term plasticity is manifested as modulation of responses peaking at ~100 ms from sound onset in functionally specialized nonprimary auditory-cortical areas by way of stimulus-specific reshaping of neuronal receptive fields that supports filtering of selectively attended sound features from task-irrelevant ones. Such effects have been shown to take effect in ~seconds following shifting of attentional focus. There are findings suggesting that the reshaping of neuronal receptive fields is even stronger at longer auditory-cortex response latencies (~300 ms from sound onset). These longer-latency short-term plasticity effects seem to build up more gradually, within tens of seconds after shifting the focus of attention. Importantly, some of the auditory-cortical short-term plasticity effects observed during selective attention predict enhancements in behaviorally measured sound discrimination performance. PMID:24551458

Predicting Future Reading Problems Based on Pre-reading Auditory Measures: A Longitudinal Study of Children with a Familial Risk of Dyslexia.

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Law, Jeremy M; Vandermosten, Maaike; Ghesquière, Pol; Wouters, Jan

2017-01-01

Purpose: This longitudinal study examines measures of temporal auditory processing in pre-reading children with a family risk of dyslexia. Specifically, it attempts to ascertain whether pre-reading auditory processing, speech perception, and phonological awareness (PA) reliably predict later literacy achievement. Additionally, this study retrospectively examines the presence of pre-reading auditory processing, speech perception, and PA impairments in children later found to be literacy impaired. Method: Forty-four pre-reading children with and without a family risk of dyslexia were assessed at three time points (kindergarten, first, and second grade). Auditory processing measures of rise time (RT) discrimination and frequency modulation (FM) along with speech perception, PA, and various literacy tasks were assessed. Results: Kindergarten RT uniquely contributed to growth in literacy in grades one and two, even after controlling for letter knowledge and PA. Highly significant concurrent and predictive correlations were observed with kindergarten RT significantly predicting first grade PA. Retrospective analysis demonstrated atypical performance in RT and PA at all three time points in children who later developed literacy impairments. Conclusions: Although significant, kindergarten auditory processing contributions to later literacy growth lack the power to be considered as a single-cause predictor; thus results support temporal processing deficits' contribution within a multiple deficit model of dyslexia.

Time computations in anuran auditory systems

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Gary J Rose

2014-05-01

Full Text Available Temporal computations are important in the acoustic communication of anurans. In many cases, calls between closely related species are nearly identical spectrally but differ markedly in temporal structure. Depending on the species, calls can differ in pulse duration, shape and/or rate (i.e., amplitude modulation, direction and rate of frequency modulation, and overall call duration. Also, behavioral studies have shown that anurans are able to discriminate between calls that differ in temporal structure. In the peripheral auditory system, temporal information is coded primarily in the spatiotemporal patterns of activity of auditory-nerve fibers. However, major transformations in the representation of temporal information occur in the central auditory system. In this review I summarize recent advances in understanding how temporal information is represented in the anuran midbrain, with particular emphasis on mechanisms that underlie selectivity for pulse duration and pulse rate (i.e., intervals between onsets of successive pulses. Two types of neurons have been identified that show selectivity for pulse rate: long-interval cells respond well to slow pulse rates but fail to spike or respond phasically to fast pulse rates; conversely, interval-counting neurons respond to intermediate or fast pulse rates, but only after a threshold number of pulses, presented at optimal intervals, have occurred. Duration-selectivity is manifest as short-pass, band-pass or long-pass tuning. Whole-cell patch recordings, in vivo, suggest that excitation and inhibition are integrated in diverse ways to generate temporal selectivity. In many cases, activity-related enhancement or depression of excitatory or inhibitory processes appear to contribute to selective responses.

Prognostic Value of Facial Nerve Antidromic Evoked Potentials in Bell Palsy: A Preliminary Study

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Zhang WenHao

2012-01-01

Full Text Available To analyze the value of facial nerve antidromic evoked potentials (FNAEPs in predicting recovery from Bell palsy. Study Design. Retrospective study using electrodiagnostic data and medical chart review. Methods. A series of 46 patients with unilateral Bell palsy treated were included. According to taste test, 26 cases were associated with taste disorder (Group 1 and 20 cases were not (Group 2. Facial function was established clinically by the Stennert system after monthly follow-up. The result was evaluated with clinical recovery rate (CRR and FNAEP. FNAEPs were recorded at the posterior wall of the external auditory meatus of both sides. Results. Mean CRR of Group 1 and Group 2 was 61.63% and 75.50%. We discovered a statistical difference between two groups and also in the amplitude difference (AD of FNAEP. Mean ± SD of AD was −6.96% ± 12.66% in patients with excellent result, −27.67% ± 27.70% with good result, and −66.05% ± 31.76% with poor result. Conclusions. FNAEP should be monitored in patients with intratemporal facial palsy at the early stage. FNAEP at posterior wall of external auditory meatus was sensitive to detect signs of taste disorder. There was close relativity between FNAEPs and facial nerve recovery.

Prognostic Value of Facial Nerve Antidromic Evoked Potentials in Bell Palsy: A Preliminary Study

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WenHao, Zhang; Minjie, Chen; Chi, Yang; Weijie, Zhang

2012-01-01

To analyze the value of facial nerve antidromic evoked potentials (FNAEPs) in predicting recovery from Bell palsy. Study Design. Retrospective study using electrodiagnostic data and medical chart review. Methods. A series of 46 patients with unilateral Bell palsy treated were included. According to taste test, 26 cases were associated with taste disorder (Group 1) and 20 cases were not (Group 2). Facial function was established clinically by the Stennert system after monthly follow-up. The result was evaluated with clinical recovery rate (CRR) and FNAEP. FNAEPs were recorded at the posterior wall of the external auditory meatus of both sides. Results. Mean CRR of Group 1 and Group 2 was 61.63% and 75.50%. We discovered a statistical difference between two groups and also in the amplitude difference (AD) of FNAEP. Mean ± SD of AD was −6.96% ± 12.66% in patients with excellent result, −27.67% ± 27.70% with good result, and −66.05% ± 31.76% with poor result. Conclusions. FNAEP should be monitored in patients with intratemporal facial palsy at the early stage. FNAEP at posterior wall of external auditory meatus was sensitive to detect signs of taste disorder. There was close relativity between FNAEPs and facial nerve recovery. PMID:22164176

Can bispectral index or auditory evoked potential index predict implicit memory during propofol-induced sedation?

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Wang, Yun; Yue, Yun; Sun, Yong-hai; Wu, An-shi

2006-06-05

Some patients still suffer from implicit memory of intraoperative events under adequate depth of anaesthesia. The elimination of implicit memory should be a necessary aim of clinical general anaesthesia. However, implicit memory cannot be tested during anaesthesia yet. We propose bispectral index (BIS) and auditory evoked potential index (AEPI), as predictors of implicit memory during anaesthesia. Thirty-six patients were equally divided into 3 groups according to the Observer's Assessment of Alertness/Sedation Score: A, level 3; B, level 2; and C, level 1. Every patient was given the first auditory stimulus before sedation. Then every patient received the second auditory stimulus after the target level of sedation had been reached. BIS and AEPI were monitored before and after the second auditory stimulus presentation. Four hours later, the inclusion test and exclusion test were performed on the ward using process dissociation procedure and the scores of implicit memory estimated. In groups A and B but not C, implicit memory estimates were statistically greater than zero (P memory scores in group A did not differ significantly from those in group B (P > 0.05). Implicit memory scores correlated with BIS and AEPI (P AEPI. The 95% cutoff points of BIS and AEPI for predicting implicit memory are 47 and 28, respectively. Implicit memory does not disappear until the depth of sedation increases to level 1 of OAA/S score. Implicit memory scores correlate well with BIS and AEPI during sedation. BIS is a better index for predicting implicit memory than AEPI during propofol induced sedation.

Small vestibular schwannomas presenting with facial nerve palsy.

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Espahbodi, Mana; Carlson, Matthew L; Fang, Te-Yung; Thompson, Reid C; Haynes, David S

2014-06-01

To describe the surgical management and convalescence of two patients presenting with severe facial nerve weakness associated with small intracanalicular vestibular schwannomas (VS). Retrospective review. Two adult female patients presenting with audiovestibular symptoms and subacute facial nerve paralysis (House-Brackmann Grade IV and V). In both cases, post-contrast T1-weighted magnetic resonance imaging revealed an enhancing lesion within the internal auditory canal without lateral extension beyond the fundus. Translabyrinthine exploration demonstrated vestibular nerve origin of tumor, extrinsic to the facial nerve, and frozen section pathology confirmed schwannoma. Gross total tumor resection with VIIth cranial nerve preservation and decompression of the labyrinthine segment of the facial nerve was performed. Both patients recovered full motor function between 6 and 8 months after surgery. Although rare, small VS may cause severe facial neuropathy, mimicking the presentation of facial nerve schwannomas and other less common pathologies. In the absence of labyrinthine extension on MRI, surgical exploration is the only reliable means of establishing a diagnosis. In the case of confirmed VS, early gross total resection with facial nerve preservation and labyrinthine segment decompression may afford full motor recovery-an outcome that cannot be achieved with facial nerve grafting.

Amelioration of Auditory Response by DA9801 in Diabetic Mouse

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Yeong Ro Lee

2015-01-01

Full Text Available Diabetes mellitus (DM is a metabolic disease that involves disorders such as diabetic retinopathy, diabetic neuropathy, and diabetic hearing loss. Recently, neurotrophin has become a treatment target that has shown to be an attractive alternative in recovering auditory function altered by DM. The aim of this study was to evaluate the effect of DA9801, a mixture of Dioscorea nipponica and Dioscorea japonica extracts, in the auditory function damage produced in a STZ-induced diabetic model and to provide evidence of the mechanisms involved in enhancing these protective effects. We found a potential application of DA9801 on hearing impairment in the STZ-induced diabetic model, demonstrated by reducing the deterioration produced by DM in ABR threshold in response to clicks and normalizing wave I–IV latencies and Pa latencies in AMLR. We also show evidence that these effects might be elicited by inducing NGF related through Nr3c1 and Akt. Therefore, this result suggests that the neuroprotective effects of DA9801 on the auditory damage produced by DM may be affected by NGF increase resulting from Nr3c1 via Akt transformation.

Validation of auditory detection response task method for assessing the attentional effects of cognitive load.

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Stojmenova, Kristina; Sodnik, Jaka

2018-07-04

There are 3 standardized versions of the Detection Response Task (DRT), 2 using visual stimuli (remote DRT and head-mounted DRT) and one using tactile stimuli. In this article, we present a study that proposes and validates a type of auditory signal to be used as DRT stimulus and evaluate the proposed auditory version of this method by comparing it with the standardized visual and tactile version. This was a within-subject design study performed in a driving simulator with 24 participants. Each participant performed 8 2-min-long driving sessions in which they had to perform 3 different tasks: driving, answering to DRT stimuli, and performing a cognitive task (n-back task). Presence of additional cognitive load and type of DRT stimuli were defined as independent variables. DRT response times and hit rates, n-back task performance, and pupil size were observed as dependent variables. Significant changes in pupil size for trials with a cognitive task compared to trials without showed that cognitive load was induced properly. Each DRT version showed a significant increase in response times and a decrease in hit rates for trials with a secondary cognitive task compared to trials without. Similar and significantly better results in differences in response times and hit rates were obtained for the auditory and tactile version compared to the visual version. There were no significant differences in performance rate between the trials without DRT stimuli compared to trials with and among the trials with different DRT stimuli modalities. The results from this study show that the auditory DRT version, using the signal implementation suggested in this article, is sensitive to the effects of cognitive load on driver's attention and is significantly better than the remote visual and tactile version for auditory-vocal cognitive (n-back) secondary tasks.

Visuo-perceptual capabilities predict sensitivity for coinciding auditory and visual transients in multi-element displays.

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Meyerhoff, Hauke S; Gehrer, Nina A

2017-01-01

In order to obtain a coherent representation of the outside world, auditory and visual information are integrated during human information processing. There is remarkable variance among observers in the capability to integrate auditory and visual information. Here, we propose that visuo-perceptual capabilities predict detection performance for audiovisually coinciding transients in multi-element displays due to severe capacity limitations in audiovisual integration. In the reported experiment, we employed an individual differences approach in order to investigate this hypothesis. Therefore, we measured performance in a useful-field-of-view task that captures detection performance for briefly presented stimuli across a large perceptual field. Furthermore, we measured sensitivity for visual direction changes that coincide with tones within the same participants. Our results show that individual differences in visuo-perceptual capabilities predicted sensitivity for the presence of audiovisually synchronous events among competing visual stimuli. To ensure that this correlation does not stem from superordinate factors, we also tested performance in an unrelated working memory task. Performance in this task was independent of sensitivity for the presence of audiovisually synchronous events. Our findings strengthen the proposed link between visuo-perceptual capabilities and audiovisual integration. The results also suggest that basic visuo-perceptual capabilities provide the basis for the subsequent integration of auditory and visual information.

From Vivaldi to Beatles and back: predicting lateralized brain responses to music.

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Alluri, Vinoo; Toiviainen, Petri; Lund, Torben E; Wallentin, Mikkel; Vuust, Peter; Nandi, Asoke K; Ristaniemi, Tapani; Brattico, Elvira

2013-12-01

We aimed at predicting the temporal evolution of brain activity in naturalistic music listening conditions using a combination of neuroimaging and acoustic feature extraction. Participants were scanned using functional Magnetic Resonance Imaging (fMRI) while listening to two musical medleys, including pieces from various genres with and without lyrics. Regression models were built to predict voxel-wise brain activations which were then tested in a cross-validation setting in order to evaluate the robustness of the hence created models across stimuli. To further assess the generalizability of the models we extended the cross-validation procedure by including another dataset, which comprised continuous fMRI responses of musically trained participants to an Argentinean tango. Individual models for the two musical medleys revealed that activations in several areas in the brain belonging to the auditory, limbic, and motor regions could be predicted. Notably, activations in the medial orbitofrontal region and the anterior cingulate cortex, relevant for self-referential appraisal and aesthetic judgments, could be predicted successfully. Cross-validation across musical stimuli and participant pools helped identify a region of the right superior temporal gyrus, encompassing the planum polare and the Heschl's gyrus, as the core structure that processed complex acoustic features of musical pieces from various genres, with or without lyrics. Models based on purely instrumental music were able to predict activation in the bilateral auditory cortices, parietal, somatosensory, and left hemispheric primary and supplementary motor areas. The presence of lyrics on the other hand weakened the prediction of activations in the left superior temporal gyrus. Our results suggest spontaneous emotion-related processing during naturalistic listening to music and provide supportive evidence for the hemispheric specialization for categorical sounds with realistic stimuli. We herewith introduce

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

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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

Optic nerve magnetisation transfer ratio after acute optic neuritis predicts axonal and visual outcomes.

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Yejun Wang

Full Text Available Magnetisation transfer ratio (MTR can reveal the degree of proton exchange between free water and macromolecules and was suggested to be pathological informative. We aimed to investigate changes in optic nerve MTR over 12 months following acute optic neuritis (ON and to determine whether MTR measurements can predict clinical and paraclinical outcomes at 6 and 12 months. Thirty-seven patients with acute ON were studied within 2 weeks of presentation and at 1, 3, 6 and 12 months. Assessments included optic nerve MTR, retinal nerve fibre layer (RNFL thickness, multifocal visual evoked potential (mfVEP amplitude and latency and high (100% and low (2.5% contrast letter acuity. Eleven healthy controls were scanned twice four weeks apart for comparison with patients. Patient unaffected optic nerve MTR did not significantly differ from controls at any time-point. Compared to the unaffected nerve, affected optic nerve MTR was significantly reduced at 3 months (mean percentage interocular difference = -9.24%, p = 0.01, 6 months (mean = -12.48%, p<0.0001 and 12 months (mean = -7.61%, p = 0.003. Greater reduction in MTR at 3 months in patients was associated with subsequent loss of high contrast letter acuity at 6 (ρ = 0.60, p = 0.0003 and 12 (ρ = 0.44, p = 0.009 months, low contrast letter acuity at 6 (ρ = 0.35, p = 0.047 months, and RNFL thinning at 12 (ρ = 0.35, p = 0.044 months. Stratification of individual patient MTR time courses based on flux over 12 months (stable, putative remyelination and putative degeneration predicted RNFL thinning at 12 months (F(2,32 = 3.59, p = 0.02. In conclusion, these findings indicate that MTR flux after acute ON is predictive of axonal degeneration and visual disability outcomes.

Development of the auditory system

Science.gov (United States)

Litovsky, Ruth

2015-01-01

Auditory development involves changes in the peripheral and central nervous system along the auditory pathways, and these occur naturally, and in response to stimulation. Human development occurs along a trajectory that can last decades, and is studied using behavioral psychophysics, as well as physiologic measurements with neural imaging. The auditory system constructs a perceptual space that takes information from objects and groups, segregates sounds, and provides meaning and access to communication tools such as language. Auditory signals are processed in a series of analysis stages, from peripheral to central. Coding of information has been studied for features of sound, including frequency, intensity, loudness, and location, in quiet and in the presence of maskers. In the latter case, the ability of the auditory system to perform an analysis of the scene becomes highly relevant. While some basic abilities are well developed at birth, there is a clear prolonged maturation of auditory development well into the teenage years. Maturation involves auditory pathways. However, non-auditory changes (attention, memory, cognition) play an important role in auditory development. The ability of the auditory system to adapt in response to novel stimuli is a key feature of development throughout the nervous system, known as neural plasticity. PMID:25726262

The effect of patient positioning on MR imaging of the internal auditory canal

International Nuclear Information System (INIS)

Daniels, D.L.; Czervionke, L.F.; Yu, S.; Ho, P.S.P.; Pech, P.; Pojunas, K.W.; Williams, A.L.; Haughton, V.M.

1988-01-01

Identification of individual cranial nerves and complete exclusion of tumor in the internal auditory canal may be difficult with MR, especially in imperfectly positioned patients. MR studies of the temporal bones in patients and in normal volunteers positioned non-rotated or canted were correlated with corresponding cryomicrotomic sections. Especially in axial images, oblique sectioning of cranial nerves VII and VIII may cause difficulty in identifying individual nerves. A combination of axial and coronal short TR and TE images can be used to confidently exclude intracanalicular tumor in most cases. (orig.)

Comparison between chloral hydrate and propofol-ketamine as sedation regimens for pediatric auditory brainstem response testing.

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Abulebda, Kamal; Patel, Vinit J; Ahmed, Sheikh S; Tori, Alvaro J; Lutfi, Riad; Abu-Sultaneh, Samer

2017-10-28

The use of diagnostic auditory brainstem response testing under sedation is currently the "gold standard" in infants and young children who are not developmentally capable of completing the test. The aim of the study is to compare a propofol-ketamine regimen to an oral chloral hydrate regimen for sedating children undergoing auditory brainstem response testing. Patients between 4 months and 6 years who required sedation for auditory brainstem response testing were included in this retrospective study. Drugs doses, adverse effects, sedation times, and the effectiveness of the sedative regimens were reviewed. 73 patients underwent oral chloral hydrate sedation, while 117 received propofol-ketamine sedation. 12% of the patients in the chloral hydrate group failed to achieve desired sedation level. The average procedure, recovery and total nursing times were significantly lower in the propofol-ketamine group. Propofol-ketamine group experienced higher incidence of transient hypoxemia. Both sedation regimens can be successfully used for sedating children undergoing auditory brainstem response testing. While deep sedation using propofol-ketamine regimen offers more efficiency than moderate sedation using chloral hydrate, it does carry a higher incidence of transient hypoxemia, which warrants the use of a highly skilled team trained in pediatric cardio-respiratory monitoring and airway management. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Role of neuronal activity in regulating the structure and function of auditory neurons

International Nuclear Information System (INIS)

Born, D.E.

1986-01-01

The role of afferent activity in maintaining neuronal structure and function was investigated in second order auditory neurons in nucleus magnocellularis (NM) of the chicken. The cochlea provides the major excitatory input to NM neurons via the eighth nerve. Removal of the cochlea causes dramatic changes in NM neurons. To determine if the elimination of neuronal activity is responsible for the changes in NM seen after cochlea removal, tetrodotoxin was used block action potentials in the cochlear ganglion cells. Tetrodotoxin injections into the perilymph reliably blocked neuronal activity in the cochlear nerve and NM. Far field recordings of sound-evoked potentials revealed that responses returned within 6 hours. Changes in amino acid incorporation in NM neurons were measured by giving intracardiac injections of 3 H-leucine and preparing tissue for autoradiographic demonstration of incorporated amino acid. Grain counts over individual neurons revealed that a single injection of tetrodotoxin produced a 40% decrease in grain density in ipsilateral NM neurons. It is concluded that neuronal activity plays an important contribution to the maintenance of the normal properties of NM neurons

A novel 9-class auditory ERP paradigm driving a predictive text entry system

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Johannes eHöhne

2011-08-01

Full Text Available Brain-Computer Interfaces (BCIs based on Event Related Potentials (ERPs strive for offering communication pathways which are independent of muscle activity. While most visual ERP-based BCI paradigms require good control of the user's gaze direction, auditory BCI paradigms overcome this restriction. The present work proposes a novel approach using Auditory Evoked Potentials (AEP for the example of a multiclass text spelling application. To control the ERP speller, BCI users focus their attention to two-dimensional auditory stimuli that vary in both, pitch (high/medium/low and direction (left/middle/right and that are presented via headphones. The resulting nine different control signals are exploited to drive a predictive text entry system. It enables the user to spell a letter by a single 9-class decision plus two additional decisions to confirm a spelled word.This paradigm - called PASS2D - was investigated in an online study with twelve healthy participants. Users spelled with more than 0.8 characters per minute on average (3.4 bits per minute which makes PASS2D a competitive method. It could enrich the toolbox of existing ERP paradigms for BCI end users like late-stage ALS patients.

Auditory agnosia due to long-term severe hydrocephalus caused by spina bifida - specific auditory pathway versus nonspecific auditory pathway.

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Zhang, Qing; Kaga, Kimitaka; Hayashi, Akimasa

2011-07-01

A 27-year-old female showed auditory agnosia after long-term severe hydrocephalus due to congenital spina bifida. After years of hydrocephalus, she gradually suffered from hearing loss in her right ear at 19 years of age, followed by her left ear. During the time when she retained some ability to hear, she experienced severe difficulty in distinguishing verbal, environmental, and musical instrumental sounds. However, her auditory brainstem response and distortion product otoacoustic emissions were largely intact in the left ear. Her bilateral auditory cortices were preserved, as shown by neuroimaging, whereas her auditory radiations were severely damaged owing to progressive hydrocephalus. Although she had a complete bilateral hearing loss, she felt great pleasure when exposed to music. After years of self-training to read lips, she regained fluent ability to communicate. Clinical manifestations of this patient indicate that auditory agnosia can occur after long-term hydrocephalus due to spina bifida; the secondary auditory pathway may play a role in both auditory perception and hearing rehabilitation.

Radioanatomy of the singular nerve canal

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Muren, C. [Dept. of Diagnostic Radiology, Sabbatsbergs Hospital, Stockholm (Sweden); Wadin, K. [University Hospital, Uppsala (Sweden); Dimopoulos, P. [University Hospital, Uppsala (Sweden)

1991-08-01

The singular canal conveys vestibular nerve fibers from the ampulla of the posterior semicircular canal to the posteroinferior border of the internal auditory meatus. Radiographic identification of this anatomic structure helps to distinguish it from a fracture. It is also a landmark in certain surgical procedures. Computed tomography (CT) examinations of deep-frozen temporal bone specimens were compared with subsequently prepared plastic casts of these bones, showing good correlation between the anatomy and the images. The singular canal and its variable anatomy were studied in CT examinations of 107 patients. The singular canal could be identified, in both the axial and in the coronal planes. Its point of entry into the internal auditory meatus varied considerably. (orig.)

Association of Concurrent fNIRS and EEG Signatures in Response to Auditory and Visual Stimuli.

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Chen, Ling-Chia; Sandmann, Pascale; Thorne, Jeremy D; Herrmann, Christoph S; Debener, Stefan

2015-09-01

Functional near-infrared spectroscopy (fNIRS) has been proven reliable for investigation of low-level visual processing in both infants and adults. Similar investigation of fundamental auditory processes with fNIRS, however, remains only partially complete. Here we employed a systematic three-level validation approach to investigate whether fNIRS could capture fundamental aspects of bottom-up acoustic processing. We performed a simultaneous fNIRS-EEG experiment with visual and auditory stimulation in 24 participants, which allowed the relationship between changes in neural activity and hemoglobin concentrations to be studied. In the first level, the fNIRS results showed a clear distinction between visual and auditory sensory modalities. Specifically, the results demonstrated area specificity, that is, maximal fNIRS responses in visual and auditory areas for the visual and auditory stimuli respectively, and stimulus selectivity, whereby the visual and auditory areas responded mainly toward their respective stimuli. In the second level, a stimulus-dependent modulation of the fNIRS signal was observed in the visual area, as well as a loudness modulation in the auditory area. Finally in the last level, we observed significant correlations between simultaneously-recorded visual evoked potentials and deoxygenated hemoglobin (DeoxyHb) concentration, and between late auditory evoked potentials and oxygenated hemoglobin (OxyHb) concentration. In sum, these results suggest good sensitivity of fNIRS to low-level sensory processing in both the visual and the auditory domain, and provide further evidence of the neurovascular coupling between hemoglobin concentration changes and non-invasive brain electrical activity.

A Decline in Response Variability Improves Neural Signal Detection during Auditory Task Performance.

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von Trapp, Gardiner; Buran, Bradley N; Sen, Kamal; Semple, Malcolm N; Sanes, Dan H

2016-10-26

The detection of a sensory stimulus arises from a significant change in neural activity, but a sensory neuron's response is rarely identical to successive presentations of the same stimulus. Large trial-to-trial variability would limit the central nervous system's ability to reliably detect a stimulus, presumably affecting perceptual performance. However, if response variability were to decrease while firing rate remained constant, then neural sensitivity could improve. Here, we asked whether engagement in an auditory detection task can modulate response variability, thereby increasing neural sensitivity. We recorded telemetrically from the core auditory cortex of gerbils, both while they engaged in an amplitude-modulation detection task and while they sat quietly listening to the identical stimuli. Using a signal detection theory framework, we found that neural sensitivity was improved during task performance, and this improvement was closely associated with a decrease in response variability. Moreover, units with the greatest change in response variability had absolute neural thresholds most closely aligned with simultaneously measured perceptual thresholds. Our findings suggest that the limitations imposed by response variability diminish during task performance, thereby improving the sensitivity of neural encoding and potentially leading to better perceptual sensitivity. The detection of a sensory stimulus arises from a significant change in neural activity. However, trial-to-trial variability of the neural response may limit perceptual performance. If the neural response to a stimulus is quite variable, then the response on a given trial could be confused with the pattern of neural activity generated when the stimulus is absent. Therefore, a neural mechanism that served to reduce response variability would allow for better stimulus detection. By recording from the cortex of freely moving animals engaged in an auditory detection task, we found that variability

Further evidence for a fluid pathway during bone conduction auditory stimulation.

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Sohmer, Haim; Freeman, Sharon

2004-07-01

This study was designed to evaluate the suggestion that during bone vibrator stimulation on skull bone (bone conduction auditory stimulation), a major connection between the site of the bone vibrator and the inner ear is a fluid pathway. A series of experiments were conducted on pairs of animals (rats or guinea pigs). The cranial cavities of each pair of animals were coupled by means of a saline filled plastic tube sealed into a craniotomy in the skull of each animal. In response to bone conduction click stimulation to the skull bone of animal I, auditory nerve-brainstem evoked responses could be recorded in animal II. Various procedures showed that these responses were initiated in animal II in response to audio-frequency sound pressures generated within the cranial cavity of animal I by the bone conduction stimulation and transferred to the cranial cavity of animal II through the fluid in the plastic tube: they were not responses to air conducted sounds generated by the bone vibrator, were not induced in animal II by vibrations conveyed to it by the plastic tube and were not electrically conducted activity from animal I. Exposing the fluid in the tube to air was not accompanied by any change in threshold. These experiments confirm that during bone conduction stimulation on the skull, audio-frequency sound pressures (alternating condensations and rarefactions) can be conveyed by a fluid pathway to the cochlea and stimulate it.

Missing and delayed auditory responses in young and older children with autism spectrum disorders

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J. Christopher eEdgar

2014-06-01

Full Text Available Background: The development of left and right superior temporal gyrus (STG 50ms (M50 and 100ms (M100 auditory responses in typically developing children (TD and in children with autism spectrum disorder (ASD was examined. It was hypothesized that (1 M50 responses would be observed equally often in younger and older children, (2 M100 responses would be observed more often in older than younger children indicating later development of secondary auditory areas, and (3 M100 but not M50 would be observed less often in ASD than TD in both age groups, reflecting slower maturation of later developing auditory areas in ASD. Methods: 35 typically developing controls, 63 ASD without language impairment (ASD-LI, and 38 ASD with language impairment (ASD+LI were recruited.The presence or absence of a STG M50 and M100 was scored. Subjects were grouped into younger (6 to 10-years-old and older groups (11 to 15-years-old. Results: Although M50 responses were observed equally often in older and younger subjects and equally often in TD and ASD, left and right M50 responses were delayed in ASD-LI and ASD+LI. Group comparisons showed that in younger subjects M100 responses were observed more often in TD than ASD+LI (90% vs 66%, p=0.04, with no differences between TD and ASD-LI (90% vs 76% p=0.14 or between ASD-LI and ASD+LI (76% vs 66%, p=0.53. In older subjects, whereas no differences were observed between TD and ASD+LI, responses were observed more often in ASD-LI than ASD+LI. Conclusions: Although present in all groups, M50 responses were delayed in ASD, suggesting delayed development of earlier developing auditory areas. Examining the TD data, findings indicated that by 11 years a right M100 should be observed in 100% of subjects and a left M100 in 80% of subjects. Thus, by 11years, lack of a left and especially right M100 offers neurobiological insight into sensory processing that may underlie language or cognitive impairment.

Does transcutaneous nerve stimulation have effect on sympathetic skin response?

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Okuyucu, E Esra; Turhanoğlu, Ayşe Dicle; Guntel, Murat; Yılmazer, Serkan; Savaş, Nazan; Mansuroğlu, Ayhan

2018-01-01

This study examined the effects of transcutaneous electrical nerve stimulation (TENS) on the sympathetic nerve system by sympathetic skin response test. Fifty-five healthy volunteers received either: (i) 30minutes TENS (25 participants) (ii) 30minutes sham TENS (30 participants) and SSR test was performed pre- and post-TENS. The mean values of latency and peak-to-peak amplitude of five consecutive SSRs were calculated. A significant amplitude difference was found between TENS and sham TENS group both in right and left hand (p=0.04, p=0.01, respectively). However there was no significant latancy difference between two groups (p>0.05 ). TENS has an inhibitory effect on elicited SNS responses when compared with sham TENS control group. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gd-DTPA enhancement of the facial nerve in Ramsay Hunt's syndrome

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Kato, Tsutomu; Yanagida, Masahiro; Yamauchi, Yasuo [Kansai Medical School, Moriguchi, Osaka (Japan); and others

1992-10-01

A total of 21 MR images in 16 Ramsay Hunt's syndrome were evaluated. In all images, the involved side of peripheral facial nerve were enhanced in intensity after Gd-DTPA. However, 2 cases had recovered facial palsy when MR images were taken. Nine of 19 cases with the enhancement of internal auditory canal portion had vertigo or tinnitus. Thus, it was suggested that the enhancement of internal auditory canal portion and clinical feature are closely related. (author).

Gd-DTPA enhancement of the facial nerve in Ramsay Hunt's syndrome

International Nuclear Information System (INIS)

Kato, Tsutomu; Yanagida, Masahiro; Yamauchi, Yasuo

1992-01-01

A total of 21 MR images in 16 Ramsay Hunt's syndrome were evaluated. In all images, the involved side of peripheral facial nerve were enhanced in intensity after Gd-DTPA. However, 2 cases had recovered facial palsy when MR images were taken. Nine of 19 cases with the enhancement of internal auditory canal portion had vertigo or tinnitus. Thus, it was suggested that the enhancement of internal auditory canal portion and clinical feature are closely related. (author)

Predictive uncertainty in auditory sequence processing

DEFF Research Database (Denmark)

Hansen, Niels Chr.; Pearce, Marcus T

2014-01-01

in a melodic sequence (inferred uncertainty). Finally, we simulate listeners' perception of expectedness and uncertainty using computational models of auditory expectation. A detailed model comparison indicates which model parameters maximize fit to the data and how they compare to existing models...

Brainstem auditory evoked potentials with the use of acoustic clicks and complex verbal sounds in young adults with learning disabilities.

Science.gov (United States)

Kouni, Sophia N; Giannopoulos, Sotirios; Ziavra, Nausika; Koutsojannis, Constantinos

2013-01-01

Acoustic signals are transmitted through the external and middle ear mechanically to the cochlea where they are transduced into electrical impulse for further transmission via the auditory nerve. The auditory nerve encodes the acoustic sounds that are conveyed to the auditory brainstem. Multiple brainstem nuclei, the cochlea, the midbrain, the thalamus, and the cortex constitute the central auditory system. In clinical practice, auditory brainstem responses (ABRs) to simple stimuli such as click or tones are widely used. Recently, complex stimuli or complex auditory brain responses (cABRs), such as monosyllabic speech stimuli and music, are being used as a tool to study the brainstem processing of speech sounds. We have used the classic 'click' as well as, for the first time, the artificial successive complex stimuli 'ba', which constitutes the Greek word 'baba' corresponding to the English 'daddy'. Twenty young adults institutionally diagnosed as dyslexic (10 subjects) or light dyslexic (10 subjects) comprised the diseased group. Twenty sex-, age-, education-, hearing sensitivity-, and IQ-matched normal subjects comprised the control group. Measurements included the absolute latencies of waves I through V, the interpeak latencies elicited by the classical acoustic click, the negative peak latencies of A and C waves, as well as the interpeak latencies of A-C elicited by the verbal stimulus 'baba' created on a digital speech synthesizer. The absolute peak latencies of waves I, III, and V in response to monoaural rarefaction clicks as well as the interpeak latencies I-III, III-V, and I-V in the dyslexic subjects, although increased in comparison with normal subjects, did not reach the level of a significant difference (pwave C and the interpeak latencies of A-C elicited by verbal stimuli were found to be increased in the dyslexic group in comparison with the control group (p=0.0004 and p=0.045, respectively). In the subgroup consisting of 10 patients suffering from

Top-Down Modulation of Auditory-Motor Integration during Speech Production: The Role of Working Memory.

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Guo, Zhiqiang; Wu, Xiuqin; Li, Weifeng; Jones, Jeffery A; Yan, Nan; Sheft, Stanley; Liu, Peng; Liu, Hanjun

2017-10-25

Although working memory (WM) is considered as an emergent property of the speech perception and production systems, the role of WM in sensorimotor integration during speech processing is largely unknown. We conducted two event-related potential experiments with female and male young adults to investigate the contribution of WM to the neurobehavioural processing of altered auditory feedback during vocal production. A delayed match-to-sample task that required participants to indicate whether the pitch feedback perturbations they heard during vocalizations in test and sample sequences matched, elicited significantly larger vocal compensations, larger N1 responses in the left middle and superior temporal gyrus, and smaller P2 responses in the left middle and superior temporal gyrus, inferior parietal lobule, somatosensory cortex, right inferior frontal gyrus, and insula compared with a control task that did not require memory retention of the sequence of pitch perturbations. On the other hand, participants who underwent extensive auditory WM training produced suppressed vocal compensations that were correlated with improved auditory WM capacity, and enhanced P2 responses in the left middle frontal gyrus, inferior parietal lobule, right inferior frontal gyrus, and insula that were predicted by pretraining auditory WM capacity. These findings indicate that WM can enhance the perception of voice auditory feedback errors while inhibiting compensatory vocal behavior to prevent voice control from being excessively influenced by auditory feedback. This study provides the first evidence that auditory-motor integration for voice control can be modulated by top-down influences arising from WM, rather than modulated exclusively by bottom-up and automatic processes. SIGNIFICANCE STATEMENT One outstanding question that remains unsolved in speech motor control is how the mismatch between predicted and actual voice auditory feedback is detected and corrected. The present study

Maturation of auditory neural processes in autism spectrum disorder — A longitudinal MEG study

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Russell G. Port

2016-01-01

Conclusions: Children with ASD showed perturbed auditory cortex neural activity, as evidenced by M100 latency delays as well as reduced transient gamma-band activity. Despite evidence for maturation of these responses in ASD, the neural abnormalities in ASD persisted across time. Of note, data from the five children whom demonstrated “optimal outcome” qualitatively suggest that such clinical improvements may be associated with auditory brain responses intermediate between TD and ASD. These “optimal outcome” related results are not statistically significant though, likely due to the low sample size of this cohort, and to be expected as a result of the relatively low proportion of “optimal outcome” in the ASD population. Thus, further investigations with larger cohorts are needed to determine if the above auditory response phenotypes have prognostic utility, predictive of clinical outcome.

Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

DEFF Research Database (Denmark)

Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

2017-01-01

-spontaneous rate fibers results in a faster recovery of wave-V latency as the slow contribution of these fibers is reduced. Results showed that in young audiometrically normal listeners, a larger change in wave-V latency with increasing masker-to-probe interval was related to a greater effect of a preceding masker......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

An analysis of nonlinear dynamics underlying neural activity related to auditory induction in the rat auditory cortex.

Science.gov (United States)

Noto, M; Nishikawa, J; Tateno, T

2016-03-24

A sound interrupted by silence is perceived as discontinuous. However, when high-intensity noise is inserted during the silence, the missing sound may be perceptually restored and be heard as uninterrupted. This illusory phenomenon is called auditory induction. Recent electrophysiological studies have revealed that auditory induction is associated with the primary auditory cortex (A1). Although experimental evidence has been accumulating, the neural mechanisms underlying auditory induction in A1 neurons are poorly understood. To elucidate this, we used both experimental and computational approaches. First, using an optical imaging method, we characterized population responses across auditory cortical fields to sound and identified five subfields in rats. Next, we examined neural population activity related to auditory induction with high temporal and spatial resolution in the rat auditory cortex (AC), including the A1 and several other AC subfields. Our imaging results showed that tone-burst stimuli interrupted by a silent gap elicited early phasic responses to the first tone and similar or smaller responses to the second tone following the gap. In contrast, tone stimuli interrupted by broadband noise (BN), considered to cause auditory induction, considerably suppressed or eliminated responses to the tone following the noise. Additionally, tone-burst stimuli that were interrupted by notched noise centered at the tone frequency, which is considered to decrease the strength of auditory induction, partially restored the second responses from the suppression caused by BN. To phenomenologically mimic the neural population activity in the A1 and thus investigate the mechanisms underlying auditory induction, we constructed a computational model from the periphery through the AC, including a nonlinear dynamical system. The computational model successively reproduced some of the above-mentioned experimental results. Therefore, our results suggest that a nonlinear, self

Intraoperative observation of changes in cochlear nerve action potentials during exposure to electromagnetic fields generated by mobile phones.

Science.gov (United States)

Colletti, Vittorio; Mandalà, Marco; Manganotti, Paolo; Ramat, Stefano; Sacchetto, Luca; Colletti, Liliana

2011-07-01

The rapid spread of devices generating electromagnetic fields (EMF) has raised concerns as to the possible effects of this technology on humans. The auditory system is the neural organ most frequently and directly exposed to electromagnetic activity owing to the daily use of mobile phones. In recent publications, a possible correlation between mobile phone usage and central nervous system tumours has been detected. Very recently a deterioration in otoacoustic emissions and in the auditory middle latency responses after intensive and long-term magnetic field exposure in humans has been demonstrated. To determine with objective observations if exposure to mobile phone EMF affects acoustically evoked cochlear nerve compound action potentials, seven patients suffering from Ménière's disease and undergoing retrosigmoid vestibular neurectomy were exposed to the effects of mobile phone placed over the craniotomy for 5 min. All patients showed a substantial decrease in amplitude and a significant increase in latency of cochlear nerve compound action potentials during the 5 min of exposure to EMF. These changes lasted for a period of around 5 min after exposure. The possibility that EMF can produce relatively long-lasting effects on cochlear nerve conduction is discussed and analysed in light of contrasting previous literature obtained under non-surgical conditions. Limitations of this novel approach, including the effects of the anaesthetics, craniotomy and surgical procedure, are presented in detail.

Reevaluation of the Amsterdam Inventory for Auditory Disability and Handicap Using Item Response Theory

Science.gov (United States)

Hospers, J. Mirjam Boeschen; Smits, Niels; Smits, Cas; Stam, Mariska; Terwee, Caroline B.; Kramer, Sophia E.

2016-01-01

Purpose: We reevaluated the psychometric properties of the Amsterdam Inventory for Auditory Disability and Handicap (AIADH; Kramer, Kapteyn, Festen, & Tobi, 1995) using item response theory. Item response theory describes item functioning along an ability continuum. Method: Cross-sectional data from 2,352 adults with and without hearing…

Wallerian degeneration: the innate-immune response to traumatic nerve injury

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Rotshenker Shlomo

2011-08-01

Full Text Available Abstract Traumatic injury to peripheral nerves results in the loss of neural functions. Recovery by regeneration depends on the cellular and molecular events of Wallerian degeneration that injury induces distal to the lesion site, the domain through which severed axons regenerate back to their target tissues. Innate-immunity is central to Wallerian degeneration since innate-immune cells, functions and molecules that are produced by immune and non-immune cells are involved. The innate-immune response helps to turn the peripheral nerve tissue into an environment that supports regeneration by removing inhibitory myelin and by upregulating neurotrophic properties. The characteristics of an efficient innate-immune response are rapid onset and conclusion, and the orchestrated interplay between Schwann cells, fibroblasts, macrophages, endothelial cells, and molecules they produce. Wallerian degeneration serves as a prelude for successful repair when these requirements are met. In contrast, functional recovery is poor when injury fails to produce the efficient innate-immune response of Wallerian degeneration.

Phencyclidine Disrupts the Auditory Steady State Response in Rats.

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Emma Leishman

Full Text Available The Auditory Steady-State Response (ASSR in the electroencephalogram (EEG is usually reduced in schizophrenia (SZ, particularly to 40 Hz stimulation. The gamma frequency ASSR deficit has been attributed to N-methyl-D-aspartate receptor (NMDAR hypofunction. We tested whether the NMDAR antagonist, phencyclidine (PCP, produced similar ASSR deficits in rats. EEG was recorded from awake rats via intracranial electrodes overlaying the auditory cortex and at the vertex of the skull. ASSRs to click trains were recorded at 10, 20, 30, 40, 50, and 55 Hz and measured by ASSR Mean Power (MP and Phase Locking Factor (PLF. In Experiment 1, the effect of different subcutaneous doses of PCP (1.0, 2.5 and 4.0 mg/kg on the ASSR in 12 rats was assessed. In Experiment 2, ASSRs were compared in PCP treated rats and control rats at baseline, after acute injection (5 mg/kg, following two weeks of subchronic, continuous administration (5 mg/kg/day, and one week after drug cessation. Acute administration of PCP increased PLF and MP at frequencies of stimulation below 50 Hz, and decreased responses at higher frequencies at the auditory cortex site. Acute administration had a less pronounced effect at the vertex site, with a reduction of either PLF or MP observed at frequencies above 20 Hz. Acute effects increased in magnitude with higher doses of PCP. Consistent effects were not observed after subchronic PCP administration. These data indicate that acute administration of PCP, a NMDAR antagonist, produces an increase in ASSR synchrony and power at low frequencies of stimulation and a reduction of high frequency (> 40 Hz ASSR activity in rats. Subchronic, continuous administration of PCP, on the other hand, has little impact on ASSRs. Thus, while ASSRs are highly sensitive to NMDAR antagonists, their translational utility as a cross-species biomarker for NMDAR hypofunction in SZ and other disorders may be dependent on dose and schedule.

Relation between derived-band auditory brainstem response latencies and behavioral frequency selectivity

DEFF Research Database (Denmark)

Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

2009-01-01

response times. For the same listeners, auditory-filter bandwidths at 2 kHz were estimated using a behavioral notched-noise masking paradigm. Generally, shorter derived-band latencies were observed for the HI than for the NH listeners. Only at low click sensation levels, prolonged latencies were obtained...

Effect of Infant Prematurity on Auditory Brainstem Response at Preschool Age

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Sara Hasani

2013-03-01

Full Text Available Introduction: Preterm birth is a risk factor for a number of conditions that requires comprehensive examination. Our study was designed to investigate the impact of preterm birth on the processing of auditory stimuli and brain structures at the brainstem level at a preschool age.   Materials and Methods: An auditory brainstem response (ABR test was performed with low rates of stimuli in 60 children aged 4 to 6 years. Thirty subjects had been born following a very preterm labor or late-preterm labor and 30 control subjects had been born following a full-term labor.   Results: Significant differences in the ABR test result were observed in terms of the inter-peak intervals of the I–III and III–V waves, and the absolute latency of the III wave (P

Echoic Memory: Investigation of Its Temporal Resolution by Auditory Offset Cortical Responses

OpenAIRE

Nishihara, Makoto; Inui, Koji; Morita, Tomoyo; Kodaira, Minori; Mochizuki, Hideki; Otsuru, Naofumi; Motomura, Eishi; Ushida, Takahiro; Kakigi, Ryusuke

2014-01-01

Previous studies showed that the amplitude and latency of the auditory offset cortical response depended on the history of the sound, which implicated the involvement of echoic memory in shaping a response. When a brief sound was repeated, the latency of the offset response depended precisely on the frequency of the repeat, indicating that the brain recognized the timing of the offset by using information on the repeat frequency stored in memory. In the present study, we investigated the temp...

Auditory hallucinations and PTSD in ex-POWS

DEFF Research Database (Denmark)

Crompton, Laura; Lahav, Yael; Solomon, Zahava

2017-01-01

(PTSD) symptoms, over time. Former prisoners of war (ex-POWs) from the 1973 Yom Kippur War (n = 99) with and without PTSD and comparable veterans (n = 103) were assessed twice, in 1991 (T1) and 2003 (T2) in regard to auditory hallucinations and PTSD symptoms. Findings indicated that ex-POWs who suffered...... from PTSD reported higher levels of auditory hallucinations at T2 as well as increased hallucinations over time, compared to ex-POWs without PTSD and combatants who did not endure captivity. The relation between PTSD and auditory hallucinations was unidirectional, so that the PTSD overall score at T1...... predicted an increase in auditory hallucinations between T1 and T2, but not vice versa. Assessing the role of PTSD clusters in predicting hallucinations revealed that intrusion symptoms had a unique contribution, compared to avoidance and hyperarousal symptoms. The findings suggest that auditory...

Neural responses to complex auditory rhythms: the role of attending

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Heather L Chapin

2010-12-01

Full Text Available The aim of this study was to explore the role of attention in pulse and meter perception using complex rhythms. We used a selective attention paradigm in which participants attended to either a complex auditory rhythm or a visually presented word list. Performance on a reproduction task was used to gauge whether participants were attending to the appropriate stimulus. We hypothesized that attention to complex rhythms – which contain no energy at the pulse frequency – would lead to activations in motor areas involved in pulse perception. Moreover, because multiple repetitions of a complex rhythm are needed to perceive a pulse, activations in pulse related areas would be seen only after sufficient time had elapsed for pulse perception to develop. Selective attention was also expected to modulate activity in sensory areas specific to the modality. We found that selective attention to rhythms led to increased BOLD responses in basal ganglia, and basal ganglia activity was observed only after the rhythms had cycled enough times for a stable pulse percept to develop. These observations suggest that attention is needed to recruit motor activations associated with the perception of pulse in complex rhythms. Moreover, attention to the auditory stimulus enhanced activity in an attentional sensory network including primary auditory, insula, anterior cingulate, and prefrontal cortex, and suppressed activity in sensory areas associated with attending to the visual stimulus.

A comparison of auditory brainstem responses across diving bird species

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Crowell, Sara E.; Berlin, Alicia; Carr, Catherine E.; Olsen, Glenn H.; Therrien, Ronald E.; Yannuzzi, Sally E.; Ketten, Darlene R.

2015-01-01

There is little biological data available for diving birds because many live in hard-to-study, remote habitats. Only one species of diving bird, the black-footed penguin (Spheniscus demersus), has been studied in respect to auditory capabilities (Wever et al., Proc Natl Acad Sci USA 63:676–680, 1969). We, therefore, measured in-air auditory threshold in ten species of diving birds, using the auditory brainstem response (ABR). The average audiogram obtained for each species followed the U-shape typical of birds and many other animals. All species tested shared a common region of the greatest sensitivity, from 1000 to 3000 Hz, although audiograms differed significantly across species. Thresholds of all duck species tested were more similar to each other than to the two non-duck species tested. The red-throated loon (Gavia stellata) and northern gannet (Morus bassanus) exhibited the highest thresholds while the lowest thresholds belonged to the duck species, specifically the lesser scaup (Aythya affinis) and ruddy duck (Oxyura jamaicensis). Vocalization parameters were also measured for each species, and showed that with the exception of the common eider (Somateria mollisima), the peak frequency, i.e., frequency at the greatest intensity, of all species' vocalizations measured here fell between 1000 and 3000 Hz, matching the bandwidth of the most sensitive hearing range.

Abnormal auditory forward masking pattern in the brainstem response of individuals with Asperger syndrome

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Johan Källstrand

2010-05-01

Full Text Available Johan Källstrand1, Olle Olsson2, Sara Fristedt Nehlstedt1, Mia Ling Sköld1, Sören Nielzén21SensoDetect AB, Lund, Sweden; 2Department of Clinical Neuroscience, Section of Psychiatry, Lund University, Lund, SwedenAbstract: Abnormal auditory information processing has been reported in individuals with autism spectrum disorders (ASD. In the present study auditory processing was investigated by recording auditory brainstem responses (ABRs elicited by forward masking in adults diagnosed with Asperger syndrome (AS. Sixteen AS subjects were included in the forward masking experiment and compared to three control groups consisting of healthy individuals (n = 16, schizophrenic patients (n = 16 and attention deficit hyperactivity disorder patients (n = 16, respectively, of matching age and gender. The results showed that the AS subjects exhibited abnormally low activity in the early part of their ABRs that distinctly separated them from the three control groups. Specifically, wave III amplitudes were significantly lower in the AS group than for all the control groups in the forward masking condition (P < 0.005, which was not the case in the baseline condition. Thus, electrophysiological measurements of ABRs to complex sound stimuli (eg, forward masking may lead to a better understanding of the underlying neurophysiology of AS. Future studies may further point to specific ABR characteristics in AS individuals that separate them from individuals diagnosed with other neurodevelopmental diseases.Keywords: asperger syndrome, auditory brainstem response, forward masking, psychoacoustics

First branchial cleft fistula associated with external auditory canal stenosis and middle ear cholesteatoma.

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Abdollahi Fakhim, Shahin; Naderpoor, Masoud; Mousaviagdas, Mehrnoosh

2014-10-01

First branchial cleft anomalies manifest with duplication of the external auditory canal. This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.

Gd-DTPA-enhanced MR imaging in facial nerve paralysis

International Nuclear Information System (INIS)

Tien, R.D.; Dillon, W.P.

1989-01-01

GD-DTPA-enhanced MR imaging was used to evaluate 11 patients with facial nerve paralysis (five acute idiopathic facial palsy (Bell palsy), three chronic recurrent facial palsy, one acute facial palsy after local radiation therapy, one chronic facial dyskinesia, and one facial neuroma). In eight of 11 patients, there was marked enhancement of the infratemporal facial nerve from the labyrinthine segment to the stylomastoid foramen. Two patients had additional contrast enhancement in the internal auditory canal segment. In one patient, enhancement persisted (but to a lesser degree) 8 weeks after symptoms had resolved. In one patient, no enhancement was seen 15 months after resolution of Bell palsy. The facial neuroma was seen as a focal nodular enhancement in the mastoid segment of the facial nerve

Which nerve conduction parameters can predict spontaneous electromyographic activity in carpal tunnel syndrome?

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Chang, Chia-Wei; Lee, Wei-Ju; Liao, Yi-Chu; Chang, Ming-Hong

2013-11-01

We investigate electrodiagnostic markers to determine which parameters are the best predictors of spontaneous electromyographic (EMG) activity in carpal tunnel syndrome (CTS). We enrolled 229 patients with clinically proven and nerve conduction study (NCS)-proven CTS, as well as 100 normal control subjects. All subjects were evaluated using electrodiagnostic techniques, including median distal sensory latencies (DSLs), sensory nerve action potentials (SNAPs), distal motor latencies (DMLs), compound muscle action potentials (CMAPs), forearm median nerve conduction velocities (FMCVs) and wrist-palm motor conduction velocities (W-P MCVs). All CTS patients underwent EMG examination of the abductor pollicis brevis (APB) muscle, and the presence or absence of spontaneous EMG activities was recorded. Normal limits were determined by calculating the means ± 2 standard deviations from the control data. Associations between parameters from the NCS and EMG findings were investigated. In patients with clinically diagnosed CTS, abnormal median CMAP amplitudes were the best predictors of spontaneous activity during EMG examination (p95% (positive predictive rate >95%). If the median CMAP amplitude was higher than the normal limit (>4.9 mV), the rate of no spontaneous EMG activity was >94% (negative predictive rate >94%). An abnormal SNAP amplitude was the second best predictor of spontaneous EMG activity (p<0.001; OR 4.13; 95% CI 2.16-7.90), and an abnormal FMCV was the third best predictor (p=0.01; OR 2.10; 95% CI 1.20-3.67). No other nerve conduction parameters had significant power to predict spontaneous activity upon EMG examination. The CMAP amplitudes of the APB are the most powerful predictors of the occurrence of spontaneous EMG activity. Low CMAP amplitudes are strongly associated with spontaneous activity, whereas high CMAP amplitude are less associated with spontaneous activity, implying that needle EMG examination should be recommended for the detection of

Echoic memory: investigation of its temporal resolution by auditory offset cortical responses.

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Nishihara, Makoto; Inui, Koji; Morita, Tomoyo; Kodaira, Minori; Mochizuki, Hideki; Otsuru, Naofumi; Motomura, Eishi; Ushida, Takahiro; Kakigi, Ryusuke

2014-01-01

Previous studies showed that the amplitude and latency of the auditory offset cortical response depended on the history of the sound, which implicated the involvement of echoic memory in shaping a response. When a brief sound was repeated, the latency of the offset response depended precisely on the frequency of the repeat, indicating that the brain recognized the timing of the offset by using information on the repeat frequency stored in memory. In the present study, we investigated the temporal resolution of sensory storage by measuring auditory offset responses with magnetoencephalography (MEG). The offset of a train of clicks for 1 s elicited a clear magnetic response at approximately 60 ms (Off-P50m). The latency of Off-P50m depended on the inter-stimulus interval (ISI) of the click train, which was the longest at 40 ms (25 Hz) and became shorter with shorter ISIs (2.5∼20 ms). The correlation coefficient r2 for the peak latency and ISI was as high as 0.99, which suggested that sensory storage for the stimulation frequency accurately determined the Off-P50m latency. Statistical analysis revealed that the latency of all pairs, except for that between 200 and 400 Hz, was significantly different, indicating the very high temporal resolution of sensory storage at approximately 5 ms.

Echoic memory: investigation of its temporal resolution by auditory offset cortical responses.

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Makoto Nishihara

Full Text Available Previous studies showed that the amplitude and latency of the auditory offset cortical response depended on the history of the sound, which implicated the involvement of echoic memory in shaping a response. When a brief sound was repeated, the latency of the offset response depended precisely on the frequency of the repeat, indicating that the brain recognized the timing of the offset by using information on the repeat frequency stored in memory. In the present study, we investigated the temporal resolution of sensory storage by measuring auditory offset responses with magnetoencephalography (MEG. The offset of a train of clicks for 1 s elicited a clear magnetic response at approximately 60 ms (Off-P50m. The latency of Off-P50m depended on the inter-stimulus interval (ISI of the click train, which was the longest at 40 ms (25 Hz and became shorter with shorter ISIs (2.5∼20 ms. The correlation coefficient r2 for the peak latency and ISI was as high as 0.99, which suggested that sensory storage for the stimulation frequency accurately determined the Off-P50m latency. Statistical analysis revealed that the latency of all pairs, except for that between 200 and 400 Hz, was significantly different, indicating the very high temporal resolution of sensory storage at approximately 5 ms.

Auditory Connections and Functions of Prefrontal Cortex

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Bethany ePlakke

2014-07-01

Full Text Available The functional auditory system extends from the ears to the frontal lobes with successively more complex functions occurring as one ascends the hierarchy of the nervous system. Several areas of the frontal lobe receive afferents from both early and late auditory processing regions within the temporal lobe. Afferents from the early part of the cortical auditory system, the auditory belt cortex, which are presumed to carry information regarding auditory features of sounds, project to only a few prefrontal regions and are most dense in the ventrolateral prefrontal cortex (VLPFC. In contrast, projections from the parabelt and the rostral superior temporal gyrus (STG most likely convey more complex information and target a larger, widespread region of the prefrontal cortex. Neuronal responses reflect these anatomical projections as some prefrontal neurons exhibit responses to features in acoustic stimuli, while other neurons display task-related responses. For example, recording studies in non-human primates indicate that VLPFC is responsive to complex sounds including vocalizations and that VLPFC neurons in area 12/47 respond to sounds with similar acoustic morphology. In contrast, neuronal responses during auditory working memory involve a wider region of the prefrontal cortex. In humans, the frontal lobe is involved in auditory detection, discrimination, and working memory. Past research suggests that dorsal and ventral subregions of the prefrontal cortex process different types of information with dorsal cortex processing spatial/visual information and ventral cortex processing non-spatial/auditory information. While this is apparent in the non-human primate and in some neuroimaging studies, most research in humans indicates that specific task conditions, stimuli or previous experience may bias the recruitment of specific prefrontal regions, suggesting a more flexible role for the frontal lobe during auditory cognition.

Auditory connections and functions of prefrontal cortex

Science.gov (United States)

Plakke, Bethany; Romanski, Lizabeth M.

2014-01-01

The functional auditory system extends from the ears to the frontal lobes with successively more complex functions occurring as one ascends the hierarchy of the nervous system. Several areas of the frontal lobe receive afferents from both early and late auditory processing regions within the temporal lobe. Afferents from the early part of the cortical auditory system, the auditory belt cortex, which are presumed to carry information regarding auditory features of sounds, project to only a few prefrontal regions and are most dense in the ventrolateral prefrontal cortex (VLPFC). In contrast, projections from the parabelt and the rostral superior temporal gyrus (STG) most likely convey more complex information and target a larger, widespread region of the prefrontal cortex. Neuronal responses reflect these anatomical projections as some prefrontal neurons exhibit responses to features in acoustic stimuli, while other neurons display task-related responses. For example, recording studies in non-human primates indicate that VLPFC is responsive to complex sounds including vocalizations and that VLPFC neurons in area 12/47 respond to sounds with similar acoustic morphology. In contrast, neuronal responses during auditory working memory involve a wider region of the prefrontal cortex. In humans, the frontal lobe is involved in auditory detection, discrimination, and working memory. Past research suggests that dorsal and ventral subregions of the prefrontal cortex process different types of information with dorsal cortex processing spatial/visual information and ventral cortex processing non-spatial/auditory information. While this is apparent in the non-human primate and in some neuroimaging studies, most research in humans indicates that specific task conditions, stimuli or previous experience may bias the recruitment of specific prefrontal regions, suggesting a more flexible role for the frontal lobe during auditory cognition. PMID:25100931

Dynamic crossmodal links revealed by steady-state responses in auditory-visual divided attention.

Science.gov (United States)

de Jong, Ritske; Toffanin, Paolo; Harbers, Marten

2010-01-01

Frequency tagging has been often used to study intramodal attention but not intermodal attention. We used EEG and simultaneous frequency tagging of auditory and visual sources to study intermodal focused and divided attention in detection and discrimination performance. Divided-attention costs were smaller, but still significant, in detection than in discrimination. The auditory steady-state response (SSR) showed no effects of attention at frontocentral locations, but did so at occipital locations where it was evident only when attention was divided between audition and vision. Similarly, the visual SSR at occipital locations was substantially enhanced when attention was divided across modalities. Both effects were equally present in detection and discrimination. We suggest that both effects reflect a common cause: An attention-dependent influence of auditory information processing on early cortical stages of visual information processing, mediated by enhanced effective connectivity between the two modalities under conditions of divided attention. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Cortical Representations of Speech in a Multitalker Auditory Scene.

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Puvvada, Krishna C; Simon, Jonathan Z

2017-09-20

The ability to parse a complex auditory scene into perceptual objects is facilitated by a hierarchical auditory system. Successive stages in the hierarchy transform an auditory scene of multiple overlapping sources, from peripheral tonotopically based representations in the auditory nerve, into perceptually distinct auditory-object-based representations in the auditory cortex. Here, using magnetoencephalography recordings from men and women, we investigate how a complex acoustic scene consisting of multiple speech sources is represented in distinct hierarchical stages of the auditory cortex. Using systems-theoretic methods of stimulus reconstruction, we show that the primary-like areas in the auditory cortex contain dominantly spectrotemporal-based representations of the entire auditory scene. Here, both attended and ignored speech streams are represented with almost equal fidelity, and a global representation of the full auditory scene with all its streams is a better candidate neural representation than that of individual streams being represented separately. We also show that higher-order auditory cortical areas, by contrast, represent the attended stream separately and with significantly higher fidelity than unattended streams. Furthermore, the unattended background streams are more faithfully represented as a single unsegregated background object rather than as separated objects. Together, these findings demonstrate the progression of the representations and processing of a complex acoustic scene up through the hierarchy of the human auditory cortex. SIGNIFICANCE STATEMENT Using magnetoencephalography recordings from human listeners in a simulated cocktail party environment, we investigate how a complex acoustic scene consisting of multiple speech sources is represented in separate hierarchical stages of the auditory cortex. We show that the primary-like areas in the auditory cortex use a dominantly spectrotemporal-based representation of the entire auditory

Quantifying stimulus-response rehabilitation protocols by auditory feedback in Parkinson's disease gait pattern

Science.gov (United States)

Pineda, Gustavo; Atehortúa, Angélica; Iregui, Marcela; García-Arteaga, Juan D.; Romero, Eduardo

2017-11-01

External auditory cues stimulate motor related areas of the brain, activating motor ways parallel to the basal ganglia circuits and providing a temporary pattern for gait. In effect, patients may re-learn motor skills mediated by compensatory neuroplasticity mechanisms. However, long term functional gains are dependent on the nature of the pathology, follow-up is usually limited and reinforcement by healthcare professionals is crucial. Aiming to cope with these challenges, several researches and device implementations provide auditory or visual stimulation to improve Parkinsonian gait pattern, inside and outside clinical scenarios. The current work presents a semiautomated strategy for spatio-temporal feature extraction to study the relations between auditory temporal stimulation and spatiotemporal gait response. A protocol for auditory stimulation was built to evaluate the integrability of the strategy in the clinic practice. The method was evaluated in transversal measurement with an exploratory group of people with Parkinson's (n = 12 in stage 1, 2 and 3) and control subjects (n =6). The result showed a strong linear relation between auditory stimulation and cadence response in control subjects (R=0.98 +/-0.008) and PD subject in stage 2 (R=0.95 +/-0.03) and stage 3 (R=0.89 +/-0.05). Normalized step length showed a variable response between low and high gait velocity (0.2> R >0.97). The correlation between normalized mean velocity and stimulus was strong in all PD stage 2 (R>0.96) PD stage 3 (R>0.84) and controls (R>0.91) for all experimental conditions. Among participants, the largest variation from baseline was found in PD subject in stage 3 (53.61 +/-39.2 step/min, 0.12 +/- 0.06 in step length and 0.33 +/- 0.16 in mean velocity). In this group these values were higher than the own baseline. These variations are related with direct effect of metronome frequency on cadence and velocity. The variation of step length involves different regulation strategies and

Using auditory steady state responses to outline the functional connectivity in the tinnitus brain.

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Winfried Schlee

Full Text Available BACKGROUND: Tinnitus is an auditory phantom perception that is most likely generated in the central nervous system. Most of the tinnitus research has concentrated on the auditory system. However, it was suggested recently that also non-auditory structures are involved in a global network that encodes subjective tinnitus. We tested this assumption using auditory steady state responses to entrain the tinnitus network and investigated long-range functional connectivity across various non-auditory brain regions. METHODS AND FINDINGS: Using whole-head magnetoencephalography we investigated cortical connectivity by means of phase synchronization in tinnitus subjects and healthy controls. We found evidence for a deviating pattern of long-range functional connectivity in tinnitus that was strongly correlated with individual ratings of the tinnitus percept. Phase couplings between the anterior cingulum and the right frontal lobe and phase couplings between the anterior cingulum and the right parietal lobe showed significant condition x group interactions and were correlated with the individual tinnitus distress ratings only in the tinnitus condition and not in the control conditions. CONCLUSIONS: To the best of our knowledge this is the first study that demonstrates existence of a global tinnitus network of long-range cortical connections outside the central auditory system. This result extends the current knowledge of how tinnitus is generated in the brain. We propose that this global extend of the tinnitus network is crucial for the continuos perception of the tinnitus tone and a therapeutical intervention that is able to change this network should result in relief of tinnitus.

Linear and nonlinear auditory response properties of interneurons in a high-order avian vocal motor nucleus during wakefulness.

Science.gov (United States)

Raksin, Jonathan N; Glaze, Christopher M; Smith, Sarah; Schmidt, Marc F

2012-04-01

Motor-related forebrain areas in higher vertebrates also show responses to passively presented sensory stimuli. However, sensory tuning properties in these areas, especially during wakefulness, and their relation to perception, are poorly understood. In the avian song system, HVC (proper name) is a vocal-motor structure with auditory responses well defined under anesthesia but poorly characterized during wakefulness. We used a large set of stimuli including the bird's own song (BOS) and many conspecific songs (CON) to characterize auditory tuning properties in putative interneurons (HVC(IN)) during wakefulness. Our findings suggest that HVC contains a diversity of responses that vary in overall excitability to auditory stimuli, as well as bias in spike rate increases to BOS over CON. We used statistical tests to classify cells in order to further probe auditory responses, yielding one-third of neurons that were either unresponsive or suppressed and two-thirds with excitatory responses to one or more stimuli. A subset of excitatory neurons were tuned exclusively to BOS and showed very low linearity as measured by spectrotemporal receptive field analysis (STRF). The remaining excitatory neurons responded well to CON stimuli, although many cells still expressed a bias toward BOS. These findings suggest the concurrent presence of a nonlinear and a linear component to responses in HVC, even within the same neuron. These characteristics are consistent with perceptual deficits in distinguishing BOS from CON stimuli following lesions of HVC and other song nuclei and suggest mirror neuronlike qualities in which "self" (here BOS) is used as a referent to judge "other" (here CON).

Amplitude by peak interaction but no evidence of auditory mismatch response deficits to frequency change in preschool age children with FASD.

Science.gov (United States)

Kabella, Danielle M; Flynn, Lucinda; Peters, Amanda; Kodituwakku, Piyadasa; Stephen, Julia M

2018-05-24

Prior studies indicate that the auditory mismatch response is sensitive to early alterations in brain development in multiple developmental disorders. Prenatal alcohol exposure is known to impact early auditory processing. The current study hypothesized alterations in the mismatch response in young children with FASD. Participants in this study were 9 children with a fetal alcohol spectrum disorder and 17 control children (Control) aged 3 to 6 years. Participants underwent MEG and structural MRI scans separately. We compared groups on neurophysiological Mismatch Negativity (MMN) responses to auditory stimuli measured using the auditory oddball paradigm. Frequent (1000 Hz) and rare (1200Hz) tones were presented at 72 dB. There was no significant group difference in MMN response latency or amplitude represented by the peak located ~200 ms after stimulus presentation in the difference timecourse between frequent and infrequent tones. Examining the timecourses to the frequent and infrequent tones separately, RM-ANOVA with condition (frequent vs. rare), peak (N100m and N200m), and hemisphere as within-subject factors and diagnosis and sex as the between-subject factors showed a significant interaction of peak by diagnosis (p = 0.001), with a pattern of decreased amplitude from N100m to N200m in Control children and the opposite pattern in children with FASD. However, no significant difference was found with the simple effects comparisons. No group differences were found in the response latencies of the rare auditory evoked fields (AEFs). The results indicate that there was no detectable effect of alcohol exposure on the amplitude or latency of the MMNm response to simple tones modulated by frequency change in preschool-age children with FASD. However, while discrimination abilities to simple tones may be intact, early auditory sensory processing revealed by the interaction between N100m and N200m amplitude indicates that auditory sensory processing may be altered in

Gd-DTPA enhancement of the facial nerve in Ramsay Hunt's syndrome

Energy Technology Data Exchange (ETDEWEB)

Kato, Tsutomu; Yanagida, Masahiro; Yamauchi, Yasuo (Kansai Medical School, Moriguchi, Osaka (Japan)) (and others)

1992-10-01

A total of 21 MR images in 16 Ramsay Hunt's syndrome were evaluated. In all images, the involved side of peripheral facial nerve were enhanced in intensity after Gd-DTPA. However, 2 cases had recovered facial palsy when MR images were taken. Nine of 19 cases with the enhancement of internal auditory canal portion had vertigo or tinnitus. Thus, it was suggested that the enhancement of internal auditory canal portion and clinical feature are closely related. (author).

Nerve conduction and excitability studies in peripheral nerve disorders

DEFF Research Database (Denmark)

Krarup, Christian; Moldovan, Mihai

2009-01-01

counterparts in the peripheral nervous system, in some instances without peripheral nervous system symptoms. Both hereditary and acquired demyelinating neuropathies have been studied and the effects on nerve pathophysiology have been compared with degeneration and regeneration of axons. SUMMARY: Excitability......PURPOSE OF REVIEW: The review is aimed at providing information about the role of nerve excitability studies in peripheral nerve disorders. It has been known for many years that the insight into peripheral nerve pathophysiology provided by conventional nerve conduction studies is limited. Nerve...... excitability studies are relatively novel but are acquiring an increasingly important role in the study of peripheral nerves. RECENT FINDINGS: By measuring responses in nerve that are related to nodal function (strength-duration time constant, rheobase and recovery cycle) and internodal function (threshold...

Sensitivity, Specificity, Predictive Values, and Accuracy of Three Diagnostic Tests to Predict Inferior Alveolar Nerve Blockade Failure in Symptomatic Irreversible Pulpitis

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Daniel Chavarría-Bolaños

2017-01-01

Full Text Available Introduction. The inferior alveolar nerve block (IANB is the most common anesthetic technique used on mandibular teeth during root canal treatment. Its success in the presence of preoperative inflammation is still controversial. The aim of this study was to evaluate the sensitivity, specificity, predictive values, and accuracy of three diagnostic tests used to predict IANB failure in symptomatic irreversible pulpitis (SIP. Methodology. A cross-sectional study was carried out on the mandibular molars of 53 patients with SIP. All patients received a single cartridge of mepivacaine 2% with 1 : 100000 epinephrine using the IANB technique. Three diagnostic clinical tests were performed to detect anesthetic failure. Anesthetic failure was defined as a positive painful response to any of the three tests. Sensitivity, specificity, predictive values, accuracy, and ROC curves were calculated and compared and significant differences were analyzed. Results. IANB failure was determined in 71.7% of the patients. The sensitivity scores for the three tests (lip numbness, the cold stimuli test, and responsiveness during endodontic access were 0.03, 0.35, and 0.55, respectively, and the specificity score was determined as 1 for all of the tests. Clinically, none of the evaluated tests demonstrated a high enough accuracy (0.30, 0.53, and 0.68 for lip numbness, the cold stimuli test, and responsiveness during endodontic access, resp.. A comparison of the areas under the curve in the ROC analyses showed statistically significant differences between the three tests (p<0.05. Conclusion. None of the analyzed tests demonstrated a high enough accuracy to be considered a reliable diagnostic tool for the prediction of anesthetic failure.

Effectiveness of auditory and tactile crossmodal cues in a dual-task visual and auditory scenario.

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Hopkins, Kevin; Kass, Steven J; Blalock, Lisa Durrance; Brill, J Christopher

2017-05-01

In this study, we examined how spatially informative auditory and tactile cues affected participants' performance on a visual search task while they simultaneously performed a secondary auditory task. Visual search task performance was assessed via reaction time and accuracy. Tactile and auditory cues provided the approximate location of the visual target within the search display. The inclusion of tactile and auditory cues improved performance in comparison to the no-cue baseline conditions. In comparison to the no-cue conditions, both tactile and auditory cues resulted in faster response times in the visual search only (single task) and visual-auditory (dual-task) conditions. However, the effectiveness of auditory and tactile cueing for visual task accuracy was shown to be dependent on task-type condition. Crossmodal cueing remains a viable strategy for improving task performance without increasing attentional load within a singular sensory modality. Practitioner Summary: Crossmodal cueing with dual-task performance has not been widely explored, yet has practical applications. We examined the effects of auditory and tactile crossmodal cues on visual search performance, with and without a secondary auditory task. Tactile cues aided visual search accuracy when also engaged in a secondary auditory task, whereas auditory cues did not.

Auditory short-term memory in the primate auditory cortex.

Science.gov (United States)

Scott, Brian H; Mishkin, Mortimer

2016-06-01

Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory. Published by Elsevier B.V.

Event-related potential response to auditory social stimuli, parent-reported social communicative deficits and autism risk in school-aged children with congenital visual impairment

Directory of Open Access Journals (Sweden)

Joe Bathelt

2017-10-01

Full Text Available Communication with visual signals, like facial expression, is important in early social development, but the question if these signals are necessary for typical social development remains to be addressed. The potential impact on social development of being born with no or very low levels of vision is therefore of high theoretical and clinical interest. The current study investigated event-related potential responses to basic social stimuli in a rare group of school-aged children with congenital visual disorders of the anterior visual system (globe of the eye, retina, anterior optic nerve. Early-latency event-related potential responses showed no difference between the VI and control group, suggesting similar initial auditory processing. However, the mean amplitude over central and right frontal channels between 280 and 320 ms was reduced in response to own-name stimuli, but not control stimuli, in children with VI suggesting differences in social processing. Children with VI also showed an increased rate of autistic-related behaviours, pragmatic language deficits, as well as peer relationship and emotional problems on standard parent questionnaires. These findings suggest that vision may be necessary for the typical development of social processing across modalities.

Verbal working memory deficits predict levels of auditory hallucination in first-episode psychosis.

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Gisselgård, Jens; Anda, Liss Gøril; Brønnick, Kolbjørn; Langeveld, Johannes; Ten Velden Hegelstad, Wenche; Joa, Inge; Johannessen, Jan Olav; Larsen, Tor Ketil

2014-03-01

Auditory verbal hallucinations are a characteristic symptom in schizophrenia. Recent causal models of auditory verbal hallucinations propose that cognitive mechanisms involving verbal working memory are involved in the genesis of auditory verbal hallucinations. Thus, in the present study, we investigate the hypothesis that verbal working memory is a specific factor behind auditory verbal hallucinations. In the present study, we investigated the association between verbal working memory manipulation (Backward Digit Span and Letter-Number Sequencing) and auditory verbal hallucinations in a population study (N=52) of first episode psychosis. The degree of auditory verbal hallucination as reported in the P3-subscale of the PANSS interview was included as dependent variable using sequential multiple regression, while controlling for age, psychosis symptom severity, executive cognitive functions and simple auditory working memory span. Multiple sequential regression analyses revealed verbal working memory manipulation to be the only significant predictor of verbal hallucination severity. Consistent with cognitive data from auditory verbal hallucinations in healthy individuals, the present results suggest a specific association between auditory verbal hallucinations, and cognitive processes involving the manipulation of phonological representations during a verbal working memory task. Copyright © 2014 Elsevier B.V. All rights reserved.

Auditory-steady-state response reliability in the audiological diagnosis after neonatal hearing screening.

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Núñez-Batalla, Faustino; Noriega-Iglesias, Sabel; Guntín-García, Maite; Carro-Fernández, Pilar; Llorente-Pendás, José Luis

2016-01-01

Conventional audiometry is the gold standard for quantifying and describing hearing loss. Alternative methods become necessary to assess subjects who are too young to respond reliably. Auditory evoked potentials constitute the most widely used method for determining hearing thresholds objectively; however, this stimulus is not frequency specific. The advent of the auditory steady-state response (ASSR) leads to more specific threshold determination. The current study describes and compares ASSR, auditory brainstem response (ABR) and conventional behavioural tone audiometry thresholds in a group of infants with various degrees of hearing loss. A comparison was made between ASSR, ABR and behavioural hearing thresholds in 35 infants detected in the neonatal hearing screening program. Mean difference scores (±SD) between ABR and high frequency ABR thresholds were 11.2 dB (±13) and 10.2 dB (±11). Pearson correlations between the ASSR and audiometry thresholds were 0.80 and 0.91 (500Hz); 0.84 and 0.82 (1000Hz); 0.85 and 0.84 (2000Hz); and 0.83 and 0.82 (4000Hz). The ASSR technique is a valuable extension of the clinical test battery for hearing-impaired children. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Brainstem auditory evoked responses in an equine patient population: part I--adult horses.

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Aleman, M; Holliday, T A; Nieto, J E; Williams, D C

2014-01-01

Brainstem auditory evoked response has been an underused diagnostic modality in horses as evidenced by few reports on the subject. To describe BAER findings, common clinical signs, and causes of hearing loss in adult horses. Study group, 76 horses; control group, 8 horses. Retrospective. BAER records from the Clinical Neurophysiology Laboratory were reviewed from the years of 1982 to 2013. Peak latencies, amplitudes, and interpeak intervals were measured when visible. Horses were grouped under disease categories. Descriptive statistics and a posthoc Bonferroni test were performed. Fifty-seven of 76 horses had BAER deficits. There was no breed or sex predisposition, with the exception of American Paint horses diagnosed with congenital sensorineural deafness. Eighty-six percent (n = 49/57) of the horses were younger than 16 years of age. The most common causes of BAER abnormalities were temporohyoid osteoarthropathy (THO, n = 20/20; abnormalities/total), congenital sensorineural deafness in Paint horses (17/17), multifocal brain disease (13/16), and otitis media/interna (4/4). Auditory loss was bilateral and unilateral in 74% (n = 42/57) and 26% (n = 15/57) of the horses, respectively. The most common causes of bilateral auditory loss were sensorineural deafness, THO, and multifocal brain disease whereas THO and otitis were the most common causes of unilateral deficits. Auditory deficits should be investigated in horses with altered behavior, THO, multifocal brain disease, otitis, and in horses with certain coat and eye color patterns. BAER testing is an objective and noninvasive diagnostic modality to assess auditory function in horses. Copyright © 2014 by the American College of Veterinary Internal Medicine.

Outcomes and Time to Emergence of Auditory Skills After Cochlear Implantation of Children With Charge Syndrome.

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Young, Nancy M; Tournis, Elizabeth; Sandy, Jenelle; Hoff, Stephen R; Ryan, Maura

2017-09-01

Review perioperative complications, benefits, and the timeframe over which auditory skills develop in children with CHARGE syndrome who receive a cochlear implant (CI). IRB-approved retrospective chart review of children with CHARGE syndrome who had at least 12 months of cochlear implant use. Tertiary care children's hospital. Twelve children, seven males and five females. Mean age implant = 3.5 years (1.7-8.2 yr); mean duration follow-up = 4.7 years (1.5-10.1 yr). Cochlear implantation. Auditory skills categorized into four levels, temporal bone imaging findings, perioperative complications, time to emergence of speech perception, expressive communication mode. All children imaged with magnetic resonance imaging had cochlear nerve deficiency in at least one ear. Speech awareness threshold improved with the CI compared with aided preoperative in 83% of children, with means of 51.7 dB SAT preoperative and 27.1 dB with the CI (p ≤ 0.002). Overall, four children improved to auditory Level 2 (improved detection), three obtained Level 3 (closed-set speech perception), and three had open-set speech perception with their CIs (Level 4) that was first evident at 3.5, 3.3, and 0.8 years postimplant testing. Two children had minimal or limited improvement. One child with hypoplasia of the cochlear nerve obtained open-set levels. Auditory skills may develop slowly in children with CHARGE syndrome who receive a CI but most can achieve at least improved detection. In our series, half acquired some speech perception ability. Cochlear nerve deficiency is frequent, but should not be a contraindication to implantation.

Sub-threshold cross-modal sensory interaction in the thalamus: lemniscal auditory response in the medial geniculate nucleus is modulated by somatosensory stimulation.

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Donishi, T; Kimura, A; Imbe, H; Yokoi, I; Kaneoke, Y

2011-02-03

Recent studies have highlighted cross-modal sensory modulations in the primary sensory areas in the cortex, suggesting that cross-modal sensory interactions occur at early stages in the hierarchy of sensory processing. Multi-modal sensory inputs from non-lemniscal thalamic nuclei and cortical inputs from the secondary sensory and association areas are considered responsible for the modulations. On the other hand, there is little evidence of cross-sensory modal sensitivities in lemniscal thalamic nuclei. In the present study, we were interested in a possibility that somatosensory stimulation may affect auditory response in the ventral division (MGV) of the medial geniculate nucleus (MG), a lemniscal thalamic nucleus that is considered to be dedicated to auditory uni-modal processing. Experiments were performed on anesthetized rats. Transcutaneous electrical stimulation of the hindpaw, which is thought to evoke nociception and seems unrelated to auditory processing, modulated unit discharges in response to auditory stimulation (noise bursts). The modulation was observed in the MGV and non-lemniscal auditory thalamic nuclei such as the dorsal and medial divisions of the MG. The major effect of somatosensory stimulation was suppression. The most robust suppression was induced by electrical stimuli given simultaneously with noise bursts or preceding noise bursts by 10 to 20 ms. The results indicate that the lemniscal (MGV) and non-lemniscal auditory nuclei are subject to somatosensory influence. In everyday experience intense somatosensory stimuli such as pain interrupt our ongoing hearing or interfere with clear recognition of sound. The modulation of lemniscal auditory response by somatosensory stimulation may underlie such cross-modal disturbance of auditory perception as a form of cross-modal switching of attention. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Error-dependent modulation of speech-induced auditory suppression for pitch-shifted voice feedback

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Larson Charles R

2011-06-01

Full Text Available Abstract Background The motor-driven predictions about expected sensory feedback (efference copies have been proposed to play an important role in recognition of sensory consequences of self-produced motor actions. In the auditory system, this effect was suggested to result in suppression of sensory neural responses to self-produced voices that are predicted by the efference copies during vocal production in comparison with passive listening to the playback of the identical self-vocalizations. In the present study, event-related potentials (ERPs were recorded in response to upward pitch shift stimuli (PSS with five different magnitudes (0, +50, +100, +200 and +400 cents at voice onset during active vocal production and passive listening to the playback. Results Results indicated that the suppression of the N1 component during vocal production was largest for unaltered voice feedback (PSS: 0 cents, became smaller as the magnitude of PSS increased to 200 cents, and was almost completely eliminated in response to 400 cents stimuli. Conclusions Findings of the present study suggest that the brain utilizes the motor predictions (efference copies to determine the source of incoming stimuli and maximally suppresses the auditory responses to unaltered feedback of self-vocalizations. The reduction of suppression for 50, 100 and 200 cents and its elimination for 400 cents pitch-shifted voice auditory feedback support the idea that motor-driven suppression of voice feedback leads to distinctly different sensory neural processing of self vs. non-self vocalizations. This characteristic may enable the audio-vocal system to more effectively detect and correct for unexpected errors in the feedback of self-produced voice pitch compared with externally-generated sounds.

Error-dependent modulation of speech-induced auditory suppression for pitch-shifted voice feedback.

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Behroozmand, Roozbeh; Larson, Charles R

2011-06-06

The motor-driven predictions about expected sensory feedback (efference copies) have been proposed to play an important role in recognition of sensory consequences of self-produced motor actions. In the auditory system, this effect was suggested to result in suppression of sensory neural responses to self-produced voices that are predicted by the efference copies during vocal production in comparison with passive listening to the playback of the identical self-vocalizations. In the present study, event-related potentials (ERPs) were recorded in response to upward pitch shift stimuli (PSS) with five different magnitudes (0, +50, +100, +200 and +400 cents) at voice onset during active vocal production and passive listening to the playback. Results indicated that the suppression of the N1 component during vocal production was largest for unaltered voice feedback (PSS: 0 cents), became smaller as the magnitude of PSS increased to 200 cents, and was almost completely eliminated in response to 400 cents stimuli. Findings of the present study suggest that the brain utilizes the motor predictions (efference copies) to determine the source of incoming stimuli and maximally suppresses the auditory responses to unaltered feedback of self-vocalizations. The reduction of suppression for 50, 100 and 200 cents and its elimination for 400 cents pitch-shifted voice auditory feedback support the idea that motor-driven suppression of voice feedback leads to distinctly different sensory neural processing of self vs. non-self vocalizations. This characteristic may enable the audio-vocal system to more effectively detect and correct for unexpected errors in the feedback of self-produced voice pitch compared with externally-generated sounds.

First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

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Abdollahi fakhim, Shahin; Naderpoor, Masoud; Mousaviagdas, Mehrnoosh

2014-01-01

Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal. Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. Conclusion: It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear. PMID:25320705

First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

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shahin abdollahi fakhim

2014-10-01

Full Text Available Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal.   Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection.   Conclusion:  It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.

Internal auditory canal (IAC) stenosis: imaging Findings

International Nuclear Information System (INIS)

Ortiz Jimenez, Johanna; Roa, Jose Luis; Figuero A, Ramon E

2011-01-01

Objectives: To describe the computed tomography (CT) and magnetic resonance (MR) findings in a patient with a diagnosis of internal auditory canal (IAC) stenosis. To describe the embryological development of the IAC structures and the natural history of IAC stenosis. Methods: A 4 year old girl presents with sensorineural hearing loss and bilateral recurrent otitis media. The temporal bone CT shows diminished left IAC diameter (less than 2 mm), right IAC absence and normal inner ear structures. These findings are pathognomonic for left IAC stenosis. The MR findings include left IAC stenosis and IAC neural structures absence secondary to aplasia of the vestibulocochlear nerve on each IAC . Results: Hypoplasia/aplasia of the vestibulocochlear nerve in association with IAC stenosis is an important consideration in the differential diagnosis of sensorineural hearing loss, as it is a relative contraindication for cochlear implant placement. Conclusions: IAC stenosis and vestibulocochlear nerve hypoplasia/aplasia must be excluded as an etiology of sensorineural hearing loss. The diagnosis can be made by CT and MR.

Internal auditory canal (IAC) stenosis: Imaging findings

International Nuclear Information System (INIS)

Ortiz J, Johanna; Roa, Jose L; Figueroa Ramon E

2011-01-01

Objectives: To describe the computed tomography (CT) and magnetic resonance (MR) findings in a patient with a diagnosis of internal auditory canal (IAC) stenosis. To describe the embryological development of the IAC structures and the natural history of IAC stenosis. Methods: A 4 year old girl presents with sensorineural hearing loss and bilateral recurrent otitis media. The temporal bone CT shows diminished left IAC diameter (less than 2 mm), right IAC absence and normal inner ear structures. These findings are pathognomonic for left IAC stenosis. The MR findings include left IAC stenosis and IAC neural structures absence secondary to aplasia of the vestibulocochlear nerve on each IAC. Results: Hypoplasia/aplasia of the vestibulocochlear nerve in association with IAC stenosis is an important consideration in the differential diagnosis of sensorineural hearing loss, as it is a relative contraindication for cochlear implant placement. Conclusions: IAC stenosis and vestibulocochlear nerve hypoplasia/aplasia must be excluded as an etiology of sensorineural hearing loss. The diagnosis can be made by CT and MR.

The maturational process of the auditory system in the first year of life characterized by brainstem auditory evoked potentials

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Raquel Beltrão Amorim

2009-01-01

Full Text Available The study of brainstem auditory evoked potentials (BAEP allows obtaining the electrophysiological activity generated in the cochlear nerve to the inferior colliculus. In the first months of life, a period of greater neuronal plasticity, important changes are observed in the absolute latency and inter-peak intervals of BAEP, which occur up to the completion of the maturational process, around 18 months of life in full-term newborns, when the response is similar to that of adults. OBJECTIVE: The goal of this study was to establish normal values of absolute latencies for waves I, III and V and inter-peak intervals I-III, III-V and I-V of the BAEP performed in full-term infants attending the Infant Hearing Health Program of the Speech-Language Pathology and Audiology Course at Bauru School of Dentistry, Brazil, with no risk history for hearing impairment. MATERIAL AND METHODS: The stimulation parameters were: rarefaction click stimulus presented by the 3ª insertion phone, intensity of 80 dBnHL and a rate of 21.1 c/s, band-pass filter of 30 and 3,000 Hz and average of 2,000 stimuli. A sample of 86 infants was first divided according to their gestational age in preterm (n=12 and full-term (n=74, and then according to their chronological age in three periods: P1: 0 to 29 days (n=46, P2: 30 days to 5 months 29 days (n=28 and P3: above 6 months (n= 12. RESULTS: The absolute latency of wave I was similar to that of adults, generally in the 1st month of life, demonstrating a complete process maturity of the auditory nerve. For waves III and V, there was a gradual decrease of absolute latencies with age, characterizing the maturation of axons and synaptic mechanisms in the brainstem level. CONCLUSION: Age proved to be a determining factor in the absolute latency of the BAEP components, especially those generated in the brainstem, in the first year of life.

Automatic hearing loss detection system based on auditory brainstem response

International Nuclear Information System (INIS)

Aldonate, J; Mercuri, C; Reta, J; Biurrun, J; Bonell, C; Gentiletti, G; Escobar, S; Acevedo, R

2007-01-01

Hearing loss is one of the pathologies with the highest prevalence in newborns. If it is not detected in time, it can affect the nervous system and cause problems in speech, language and cognitive development. The recommended methods for early detection are based on otoacoustic emissions (OAE) and/or auditory brainstem response (ABR). In this work, the design and implementation of an automated system based on ABR to detect hearing loss in newborns is presented. Preliminary evaluation in adults was satisfactory

Predictive value of neurological examination for early cortical responses to somatosensory evoked potentials in patients with postanoxic coma

NARCIS (Netherlands)

Bouwes, Aline; Binnekade, Jan M.; Verbaan, Bart W.; Zandbergen, Eveline G. J.; Koelman, Johannes H. T. M.; Weinstein, Henry C.; Hijdra, Albert; Horn, Janneke

2012-01-01

Bilateral absence of cortical N20 responses of median nerve somatosensory evoked potentials (SEP) predicts poor neurological outcome in postanoxic coma after cardiopulmonary resuscitation (CPR). Although SEP is easy to perform and available in most hospitals, it is worthwhile to know how

Low Levels of NDRG1 in Nerve Tissue Are Predictive of Severe Paclitaxel-Induced Neuropathy.

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Raghav Sundar

Full Text Available Sensory peripheral neuropathy caused by paclitaxel is a common and dose limiting toxicity, for which there are currently no validated predictive biomarkers. We investigated the relationship between the Charcot-Marie-Tooth protein NDRG1 and paclitaxel-induced neuropathy.Archived mammary tissue specimen blocks of breast cancer patients who received weekly paclitaxel in a single centre were retrieved and NDRG1 immunohistochemistry was performed on normal nerve tissue found within the sample. The mean nerve NDRG1 score was defined by an algorithm based on intensity of staining and percentage of stained nerve bundles. NDRG1 scores were correlated with paclitaxel induced neuropathy.111 patients were studied. 17 of 111 (15% developed severe paclitaxel-induced neuropathy. The mean nerve NDRG1 expression score was 5.4 in patients with severe neuropathy versus 7.7 in those without severe neuropathy (p = 0.0019. A Receiver operating characteristic (ROC curve analysis of the mean nerve NDRG1 score revealed an area under the curve of 0.74 (p = 0.0013 for the identification of severe neuropathy, with a score of 7 being most discriminative. 13/54 (24% subjects with an NDRG1 score 7 (p = 0.017.Low NDRG1 expression in nerve tissue present within samples of surgical resection may identify subjects at risk for severe paclitaxel-induced neuropathy. Since nerve biopsies are not routinely feasible for patients undergoing chemotherapy for early breast cancer, this promising biomarker strategy is compatible with current clinical workflow.

Optical stimulation of peripheral nerves in vivo

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Wells, Jonathon D.

This dissertation documents the emergence and validation of a new clinical tool that bridges the fields of biomedical optics and neuroscience. The research herein describes an innovative method for direct neurostimulation with pulsed infrared laser light. Safety and effectiveness of this technique are first demonstrated through functional stimulation of the rat sciatic nerve in vivo. The Holmium:YAG laser (lambda = 2.12 mum) is shown to operate at an optimal wavelength for peripheral nerve stimulation with advantages over standard electrical neural stimulation; including contact-free stimulation, high spatial selectivity, and lack of a stimulation artifact. The underlying biophysical mechanism responsible for transient optical nerve stimulation appears to be a small, absorption driven thermal gradient sustained at the axonal layer of nerve. Results explicitly prove that low frequency optical stimulation can reliably stimulate without resulting in tissue thermal damage. Based on the positive results from animal studies, these optimal laser parameters were utilized to move this research into the clinic with a combined safety and efficacy study in human subjects undergoing selective dorsal rhizotomy. The clinical Holmium:YAG laser was used to effectively stimulate human dorsal spinal roots and elicit functional muscle responses recorded during surgery without evidence of nerve damage. Overall these results predict that this technology can be a valuable clinical tool in various neurosurgical applications.

Learned helplessness and responses to nerve blocks in chronic low back pain patients.

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Chapman, S L; Brena, S F

1982-01-01

In a double-blind study, 67 chronic low back pain patients received 4 lumbar sympathetic nerve blocks, two given with bupivacaine and two given with saline. It was hypothesized that patients showing evidence of 'learned helplessness,' as measured by dependence on habit-forming medications for the pain, low activity levels, and elevated MMPI scores on Hypochondriasis, Depression and Hysteria would show the least reduction in subjective pain intensity following injections with both bupivacaine and saline. It also was hypothesized that placebo responses would be greatest in patients who had a high educational level, were divorced, and had no pending disability claims. Responses 30 min following nerve blocks failed to correlate with these variables. However, decreases in subjective pain intensity 24 h following both types of nerve blocks were greater in patients who showed low levels of pain behavior, who were divorced, and who had no pending disability claims. Decreased pain 24 h following saline injections was significantly related to low scores on the Lie, Defensiveness, Hypochondriasis, and Hysteria scales of the MMPI and to reduced subjective pain intensity following a 6 week comprehensive outpatient pain rehabilitation program. It was concluded that chronic pain patients who are fixed in their focus on pain, high in pain-related behaviors, and low in responsibilities are less likely to respond favorably to nerve blocks and that medical treatment for them needs to be paired with therapies designed to reduce their helplessness.

Retinal nerve fiber layer thickness and neuropsychiatric manifestations in systemic lupus erythematosus.

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Shulman, S; Shorer, R; Wollman, J; Dotan, G; Paran, D

2017-11-01

Background Cognitive impairment is frequent in systemic lupus erythematosus. Atrophy of the corpus callosum and hippocampus have been reported in patients with systemic lupus erythematosus, and diffusion tensor imaging studies have shown impaired white matter integrity, suggesting that white matter damage in systemic lupus erythematosus may underlie the cognitive impairment as well as other neuropsychiatric systemic lupus erythematosus manifestations. Retinal nerve fiber layer thickness, as assessed by optical coherence tomography, has been suggested as a biomarker for white matter damage in neurologic disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. Retinal nerve fiber layer thinning may occur early, even in patients with mild clinical symptoms. Aim The objective of this study was to assess the association of retinal nerve fiber layer thickness, as a biomarker of white matter damage in systemic lupus erythematosus patients, with neuropsychiatric systemic lupus erythematosus manifestations, including cognitive impairment. Methods Twenty-one consecutive patients with systemic lupus erythematosus underwent neuropsychological testing using a validated computerized battery of tests as well as the Rey-Auditory verbal learning test. All 21 patients, as well as 11 healthy, age matched controls, underwent optical coherence tomography testing to assess retinal nerve fiber layer thickness. Correlations between retinal nerve fiber layer thickness and results in eight cognitive domains assessed by the computerized battery of tests as well as the Rey-Auditory verbal learning test were assessed in patients with systemic lupus erythematosus, with and without neuropsychiatric systemic lupus erythematosus, and compared to retinal nerve fiber layer thickness in healthy controls. Results No statistically significant correlation was found between retinal nerve fiber layer thickness in patients with systemic lupus erythematosus as compared to healthy

Animal models for auditory streaming

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Itatani, Naoya

2017-01-01

Sounds in the natural environment need to be assigned to acoustic sources to evaluate complex auditory scenes. Separating sources will affect the analysis of auditory features of sounds. As the benefits of assigning sounds to specific sources accrue to all species communicating acoustically, the ability for auditory scene analysis is widespread among different animals. Animal studies allow for a deeper insight into the neuronal mechanisms underlying auditory scene analysis. Here, we will review the paradigms applied in the study of auditory scene analysis and streaming of sequential sounds in animal models. We will compare the psychophysical results from the animal studies to the evidence obtained in human psychophysics of auditory streaming, i.e. in a task commonly used for measuring the capability for auditory scene analysis. Furthermore, the neuronal correlates of auditory streaming will be reviewed in different animal models and the observations of the neurons’ response measures will be related to perception. The across-species comparison will reveal whether similar demands in the analysis of acoustic scenes have resulted in similar perceptual and neuronal processing mechanisms in the wide range of species being capable of auditory scene analysis. This article is part of the themed issue ‘Auditory and visual scene analysis’. PMID:28044022

[A comparison of time resolution among auditory, tactile and promontory electrical stimulation--superiority of cochlear implants as human communication aids].

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Matsushima, J; Kumagai, M; Harada, C; Takahashi, K; Inuyama, Y; Ifukube, T

1992-09-01

Our previous reports showed that second formant information, using a speech coding method, could be transmitted through an electrode on the promontory. However, second formant information can also be transmitted by tactile stimulation. Therefore, to find out whether electrical stimulation of the auditory nerve would be superior to tactile stimulation for our speech coding method, the time resolutions of the two modes of stimulation were compared. The results showed that the time resolution of electrical promontory stimulation was three times better than the time resolution of tactile stimulation of the finger. This indicates that electrical stimulation of the auditory nerve is much better for our speech coding method than tactile stimulation of the finger.

The pattern of auditory brainstem response wave V maturation in cochlear-implanted children.

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Thai-Van, Hung; Cozma, Sebastian; Boutitie, Florent; Disant, François; Truy, Eric; Collet, Lionel

2007-03-01

Maturation of acoustically evoked brainstem responses (ABR) in hearing children is not complete at birth but rather continues over the first two years of life. In particular, it has been established that the decrease in ABR wave V latency can be modeled as the sum of two decaying exponential functions with respective time-constants of 4 and 50 weeks [Eggermont, J.J., Salamy, A., 1988a. Maturational time-course for the ABR in preterm and full term infants. Hear Res 33, 35-47; Eggermont, J.J., Salamy, A., 1988b. Development of ABR parameters in a preterm and a term born population. Ear Hear 9, 283-9]. Here, we investigated the maturation of electrically evoked auditory brainstem responses (EABR) in 55 deaf children who recovered hearing after cochlear implantation, and proposed a predictive model of EABR maturation depending on the onset of deafness. The pattern of EABR maturation over the first 2 years of cochlear implant use was compared with the normal pattern of ABR maturation in hearing children. Changes in EABR wave V latency over the 2 years following cochlear implant connection were analyzed in two groups of children. The first group (n=41) consisted of children with early-onset of deafness (mostly congenital), and the second (n=14) of children who had become profoundly deaf after 1 year of age. The modeling of changes in EABR wave V latency with time was based on the mean values from each of the two groups, allowing comparison of the rates of EABR maturation between groups. Differences between EABRs elicited at the basal and apical ends of the implant electrode array were also tested. There was no influence of age at implantation on the rate of wave V latency change. The main factor for EABR changes was the time in sound. Indeed, significant maturation was observed over the first 2 years of implant use only in the group with early-onset deafness. In this group maturation of wave V progressed as in the ABR model of [Eggermont, J.J., Salamy, A., 1988a

Predictors of auditory performance in hearing-aid users: The role of cognitive function and auditory lifestyle (A)

DEFF Research Database (Denmark)

Vestergaard, Martin David

2006-01-01

no objective benefit can be measured. It has been suggested that lack of agreement between various hearing-aid outcome components can be explained by individual differences in cognitive function and auditory lifestyle. We measured speech identification, self-report outcome, spectral and temporal resolution...... of hearing, cognitive skills, and auditory lifestyle in 25 new hearing-aid users. The purpose was to assess the predictive power of the nonauditory measures while looking at the relationships between measures from various auditory-performance domains. The results showed that only moderate correlation exists...... between objective and subjective hearing-aid outcome. Different self-report outcome measures showed a different amount of correlation with objective auditory performance. Cognitive skills were found to play a role in explaining speech performance and spectral and temporal abilities, and auditory lifestyle...

Visual Input Enhances Selective Speech Envelope Tracking in Auditory Cortex at a ‘Cocktail Party’

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Golumbic, Elana Zion; Cogan, Gregory B.; Schroeder, Charles E.; Poeppel, David

2013-01-01

Our ability to selectively attend to one auditory signal amidst competing input streams, epitomized by the ‘Cocktail Party’ problem, continues to stimulate research from various approaches. How this demanding perceptual feat is achieved from a neural systems perspective remains unclear and controversial. It is well established that neural responses to attended stimuli are enhanced compared to responses to ignored ones, but responses to ignored stimuli are nonetheless highly significant, leading to interference in performance. We investigated whether congruent visual input of an attended speaker enhances cortical selectivity in auditory cortex, leading to diminished representation of ignored stimuli. We recorded magnetoencephalographic (MEG) signals from human participants as they attended to segments of natural continuous speech. Using two complementary methods of quantifying the neural response to speech, we found that viewing a speaker’s face enhances the capacity of auditory cortex to track the temporal speech envelope of that speaker. This mechanism was most effective in a ‘Cocktail Party’ setting, promoting preferential tracking of the attended speaker, whereas without visual input no significant attentional modulation was observed. These neurophysiological results underscore the importance of visual input in resolving perceptual ambiguity in a noisy environment. Since visual cues in speech precede the associated auditory signals, they likely serve a predictive role in facilitating auditory processing of speech, perhaps by directing attentional resources to appropriate points in time when to-be-attended acoustic input is expected to arrive. PMID:23345218

Effects of background noise on inter-trial phase coherence and auditory N1-P2 responses to speech stimuli.

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Koerner, Tess K; Zhang, Yang

2015-10-01

This study investigated the effects of a speech-babble background noise on inter-trial phase coherence (ITPC, also referred to as phase locking value (PLV)) and auditory event-related responses (AERP) to speech sounds. Specifically, we analyzed EEG data from 11 normal hearing subjects to examine whether ITPC can predict noise-induced variations in the obligatory N1-P2 complex response. N1-P2 amplitude and latency data were obtained for the /bu/syllable in quiet and noise listening conditions. ITPC data in delta, theta, and alpha frequency bands were calculated for the N1-P2 responses in the two passive listening conditions. Consistent with previous studies, background noise produced significant amplitude reduction and latency increase in N1 and P2, which were accompanied by significant ITPC decreases in all the three frequency bands. Correlation analyses further revealed that variations in ITPC were able to predict the amplitude and latency variations in N1-P2. The results suggest that trial-by-trial analysis of cortical neural synchrony is a valuable tool in understanding the modulatory effects of background noise on AERP measures. Copyright © 2015 Elsevier B.V. All rights reserved.

Self-initiated actions result in suppressed auditory but amplified visual evoked components in healthy participants.

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Mifsud, Nathan G; Oestreich, Lena K L; Jack, Bradley N; Ford, Judith M; Roach, Brian J; Mathalon, Daniel H; Whitford, Thomas J

2016-05-01

Self-suppression refers to the phenomenon that sensations initiated by our own movements are typically less salient, and elicit an attenuated neural response, compared to sensations resulting from changes in the external world. Evidence for self-suppression is provided by previous ERP studies in the auditory modality, which have found that healthy participants typically exhibit a reduced auditory N1 component when auditory stimuli are self-initiated as opposed to externally initiated. However, the literature investigating self-suppression in the visual modality is sparse, with mixed findings and experimental protocols. An EEG study was conducted to expand our understanding of self-suppression across different sensory modalities. Healthy participants experienced either an auditory (tone) or visual (pattern-reversal) stimulus following a willed button press (self-initiated), a random interval (externally initiated, unpredictable onset), or a visual countdown (externally initiated, predictable onset-to match the intrinsic predictability of self-initiated stimuli), while EEG was continuously recorded. Reduced N1 amplitudes for self- versus externally initiated tones indicated that self-suppression occurred in the auditory domain. In contrast, the visual N145 component was amplified for self- versus externally initiated pattern reversals. Externally initiated conditions did not differ as a function of their predictability. These findings highlight a difference in sensory processing of self-initiated stimuli across modalities, and may have implications for clinical disorders that are ostensibly associated with abnormal self-suppression. © 2016 Society for Psychophysiological Research.

Auditory Brainstem Response Wave Amplitude Characteristics as a Diagnostic Tool in Children with Speech Delay with Unknown Causes

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Susan Abadi

2016-09-01

Full Text Available Speech delay with an unknown cause is a problem among children. This diagnosis is the last differential diagnosis after observing normal findings in routine hearing tests. The present study was undertaken to determine whether auditory brainstem responses to click stimuli are different between normally developing children and children suffering from delayed speech with unknown causes. In this cross-sectional study, we compared click auditory brainstem responses between 261 children who were clinically diagnosed with delayed speech with unknown causes based on normal routine auditory test findings and neurological examinations and had >12 months of speech delay (case group and 261 age- and sex-matched normally developing children (control group. Our results indicated that the case group exhibited significantly higher wave amplitude responses to click stimuli (waves I, III, and V than did the control group (P=0.001. These amplitudes were significantly reduced after 1 year (P=0.001; however, they were still significantly higher than those of the control group (P=0.001. The significant differences were seen regardless of the age and the sex of the participants. There were no statistically significant differences between the 2 groups considering the latency of waves I, III, and V. In conclusion, the higher amplitudes of waves I, III, and V, which were observed in the auditory brainstem responses to click stimuli among the patients with speech delay with unknown causes, might be used as a diagnostic tool to track patients’ improvement after treatment.

Multiple time scales of adaptation in auditory cortex neurons.

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Ulanovsky, Nachum; Las, Liora; Farkas, Dina; Nelken, Israel

2004-11-17

Neurons in primary auditory cortex (A1) of cats show strong stimulus-specific adaptation (SSA). In probabilistic settings, in which one stimulus is common and another is rare, responses to common sounds adapt more strongly than responses to rare sounds. This SSA could be a correlate of auditory sensory memory at the level of single A1 neurons. Here we studied adaptation in A1 neurons, using three different probabilistic designs. We showed that SSA has several time scales concurrently, spanning many orders of magnitude, from hundreds of milliseconds to tens of seconds. Similar time scales are known for the auditory memory span of humans, as measured both psychophysically and using evoked potentials. A simple model, with linear dependence on both short-term and long-term stimulus history, provided a good fit to A1 responses. Auditory thalamus neurons did not show SSA, and their responses were poorly fitted by the same model. In addition, SSA increased the proportion of failures in the responses of A1 neurons to the adapting stimulus. Finally, SSA caused a bias in the neuronal responses to unbiased stimuli, enhancing the responses to eccentric stimuli. Therefore, we propose that a major function of SSA in A1 neurons is to encode auditory sensory memory on multiple time scales. This SSA might play a role in stream segregation and in binding of auditory objects over many time scales, a property that is crucial for processing of natural auditory scenes in cats and of speech and music in humans.

Intratemporal facial nerve neuromas and their mimics: CT and MR findings

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Han, Moon Hee; Chang, Kee Hyun; Lee, Kyung Hwan; Cha, Sang Hoon; Kim, Chong Sun [Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Sang Joon [Chungang Gil General Hospital, Seoul (Korea, Republic of)

1992-05-15

CT and MR findings of nine cases with intra temporal facial nerve neuromas were described and compared with CT findings of 3 cases with facial nerve palsy and facial nerve canal erosion which may mimic facial nerve neuroma. The tympanic segment of the facial nerve was involved in 8 cases, mastoid segment in 7 cases and labyrinthine segment in 5 cases. The lesions were easily diagnosed with high resolution CT with bone algorithms by showing the expansion of bony structures along the course of the facial nerves. In 4 cases with large vertical segment tumors, extensive destruction of mastoid air cells and external auditory canals posed difficulty in making a diagnosis. Two out of 5 cases with labyrinthine segment involvement were presented as middle cranial fossa masses. MRI with enhancement was performed in 4 cases and was useful in characterizing the lesion as a tumor with its superior sensitivity to enhancement. Three cases of facial neuroma-mimicking lesion including post-inflammatory peri neural thickening, peri neural extension from parotid adenoid cystic carcinoma, and congenita; cholesteatoma showed irregular erosion or mild expansion of the facial nerve canal which may be helpful for differential diagnosis from neuromas.

Auditory/visual distance estimation: accuracy and variability

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Paul Wallace Anderson

2014-10-01

Full Text Available Past research has shown that auditory distance estimation improves when listeners are given the opportunity to see all possible sound sources when compared to no visual input. It has also been established that distance estimation is more accurate in vision than in audition. The present study investigates the degree to which auditory distance estimation is improved when matched with a congruent visual stimulus. Virtual sound sources based on binaural room impulse response (BRIR measurements made from distances ranging from approximately 0.3 to 9.8 m in a concert hall were used as auditory stimuli. Visual stimuli were photographs taken from the listener’s perspective at each distance in the impulse response measurement setup presented on a large HDTV monitor. Listeners were asked to estimate egocentric distance to the sound source in each of three conditions: auditory only (A, visual only (V, and congruent auditory/visual stimuli (A+V. Each condition was presented within its own block. Sixty-two listeners were tested in order to quantify the response variability inherent in auditory distance perception. Distance estimates from both the V and A+V conditions were found to be considerably more accurate and less variable than estimates from the A condition.

Encoding of natural and artificial stimuli in the auditory midbrain

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Lyzwa, Dominika

How complex acoustic stimuli are encoded in the main center of convergence in the auditory midbrain is not clear. Here, the representation of neural spiking responses to natural and artificial sounds across this subcortical structure is investigated based on neurophysiological recordings from the mammalian midbrain. Neural and stimulus correlations of neuronal pairs are analyzed with respect to the neurons' distance, and responses to different natural communication sounds are discriminated. A model which includes linear and nonlinear neural response properties of this nucleus is presented and employed to predict temporal spiking responses to new sounds. Supported by BMBF Grant 01GQ0811.

A Neural Circuit for Auditory Dominance over Visual Perception.

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Song, You-Hyang; Kim, Jae-Hyun; Jeong, Hye-Won; Choi, Ilsong; Jeong, Daun; Kim, Kwansoo; Lee, Seung-Hee

2017-02-22

When conflicts occur during integration of visual and auditory information, one modality often dominates the other, but the underlying neural circuit mechanism remains unclear. Using auditory-visual discrimination tasks for head-fixed mice, we found that audition dominates vision in a process mediated by interaction between inputs from the primary visual (VC) and auditory (AC) cortices in the posterior parietal cortex (PTLp). Co-activation of the VC and AC suppresses VC-induced PTLp responses, leaving AC-induced responses. Furthermore, parvalbumin-positive (PV+) interneurons in the PTLp mainly receive AC inputs, and muscimol inactivation of the PTLp or optogenetic inhibition of its PV+ neurons abolishes auditory dominance in the resolution of cross-modal sensory conflicts without affecting either sensory perception. Conversely, optogenetic activation of PV+ neurons in the PTLp enhances the auditory dominance. Thus, our results demonstrate that AC input-specific feedforward inhibition of VC inputs in the PTLp is responsible for the auditory dominance during cross-modal integration. Copyright © 2017 Elsevier Inc. All rights reserved.

Noise perception in the workplace and auditory and extra-auditory symptoms referred by university professors.

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Servilha, Emilse Aparecida Merlin; Delatti, Marina de Almeida

2012-01-01

To investigate the correlation between noise in the work environment and auditory and extra-auditory symptoms referred by university professors. Eighty five professors answered a questionnaire about identification, functional status, and health. The relationship between occupational noise and auditory and extra-auditory symptoms was investigated. Statistical analysis considered the significance level of 5%. None of the professors indicated absence of noise. Responses were grouped in Always (A) (n=21) and Not Always (NA) (n=63). Significant sources of noise were both the yard and another class, which were classified as high intensity; poor acoustic and echo. There was no association between referred noise and health complaints, such as digestive, hormonal, osteoarticular, dental, circulatory, respiratory and emotional complaints. There was also no association between referred noise and hearing complaints, and the group A showed higher occurrence of responses regarding noise nuisance, hearing difficulty and dizziness/vertigo, tinnitus, and earache. There was association between referred noise and voice alterations, and the group NA presented higher percentage of cases with voice alterations than the group A. The university environment was considered noisy; however, there was no association with auditory and extra-auditory symptoms. The hearing complaints were more evident among professors in the group A. Professors' health is a multi-dimensional product and, therefore, noise cannot be considered the only aggravation factor.

A novel method for extraction of neural response from single channel cochlear implant auditory evoked potentials.

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Sinkiewicz, Daniel; Friesen, Lendra; Ghoraani, Behnaz

2017-02-01

Cortical auditory evoked potentials (CAEP) are used to evaluate cochlear implant (CI) patient auditory pathways, but the CI device produces an electrical artifact, which obscures the relevant information in the neural response. Currently there are multiple methods, which attempt to recover the neural response from the contaminated CAEP, but there is no gold standard, which can quantitatively confirm the effectiveness of these methods. To address this crucial shortcoming, we develop a wavelet-based method to quantify the amount of artifact energy in the neural response. In addition, a novel technique for extracting the neural response from single channel CAEPs is proposed. The new method uses matching pursuit (MP) based feature extraction to represent the contaminated CAEP in a feature space, and support vector machines (SVM) to classify the components as normal hearing (NH) or artifact. The NH components are combined to recover the neural response without artifact energy, as verified using the evaluation tool. Although it needs some further evaluation, this approach is a promising method of electrical artifact removal from CAEPs. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Acute corneal epithelial debridement unmasks the corneal stromal nerve responses to ocular stimulation in rats: implications for abnormal sensations of the eye.

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Hirata, Harumitsu; Mizerska, Kamila; Dallacasagrande, Valentina; Guaiquil, Victor H; Rosenblatt, Mark I

2017-05-01

It is widely accepted that the mechanisms for transducing sensory information reside in the nerve terminals. Occasionally, however, studies have appeared demonstrating that similar mechanisms may exist in the axon to which these terminals are connected. We examined this issue in the cornea, where nerve terminals in the epithelial cell layers are easily accessible for debridement, leaving the underlying stromal (axonal) nerves undisturbed. In isoflurane-anesthetized rats, we recorded extracellularly from single trigeminal ganglion neurons innervating the cornea that are excited by ocular dryness and cooling: low-threshold (2°C) cold-sensitive plus dry-sensitive neurons playing possible roles in tearing and ocular pain. We found that the responses in both types of neurons to dryness, wetness, and menthol stimuli were effectively abolished by the debridement, indicating that their transduction mechanisms lie in the nerve terminals. However, some responses to the cold, heat, and hyperosmolar stimuli in low-threshold cold-sensitive plus dry-sensitive neurons still remained. Surprisingly, the responses to heat in approximately half of the neurons were augmented after the debridement. We were also able to evoke these residual responses and follow the trajectory of the stromal nerves, which we subsequently confirmed histologically. The residual responses always disappeared when the stromal nerves were cut at the limbus, suggesting that the additional transduction mechanisms for these sensory modalities originated most likely in stromal nerves. The functional significance of these residual and enhanced responses from stromal nerves may be related to the abnormal sensations observed in ocular disease. NEW & NOTEWORTHY In addition to the traditional view that the sensory transduction mechanisms exist in the nerve terminals, we report here that the proximal axons (stromal nerves in the cornea from which these nerve terminals originate) may also be capable of transducing

Cerebellopontine angle and internal auditory canal: neurovascular anatomy on gas CT cisternograms

International Nuclear Information System (INIS)

Bird, C.R.; Hasso, A.N.; Drayer, B.P.; Hinshaw, D.B. Jr.; Thompson, J.R.

1985-01-01

The authors reviewed 103 normal gas CT cisternograms to delineate the appearance of normal neurovascular structures in the cerebellopontine angle (CPA) and internal auditory canal (IAC). Cranial nerves VII and VIII were identified in the CPA in 97% of cases, either separately (53%) or as a bundle (44%). Intracanalicular branches of the VIIIth cranial nerve were identified in 20% of cases, and cranial nerve V was visualized in the CPA in 14%. The characteristic vascular loop, usually the anterior inferior cerebellar artery, was visible in 35% of cases, and, in 22% of visualized cases, was in an intracanalicular location. In 10% of cases, greater than 66% of the IAC was occupied by the neurovascular bundle. Familiarity with the normal anatomy and variations seen on gas CT cisternograms is necessary to prevent false-positive interpretations

Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing intraoperative neurophysiological monitoring.

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Jahangiri, Faisal R; Minhas, Mazhar; Jane, John

2012-12-01

We present two cases illustrating the benefit of utilizing intraoperative neurophysiological monitoring (IONM) for prevention of injuries to the lower cranial nerves during fourth ventricle tumor resection surgeries. Multiple cranial nerve nuclei are located on the floor of the fourth ventricle with a high risk of permanent damage. Two male patients (ages 8 and 10 years) presented to the emergency department and had brain magnetic resonance imaging (MRI) scans showing brainstem/fourth ventricle tumors. During surgery, bilateral posterior tibial and median nerve somatosensory evoked potentials (SSEPs); four-limb and cranial nerves transcranial electrical motor evoked potentials (TCeMEPs); brainstem auditory evoked responses (BAERs); and spontaneous electromyography (s-EMG) were recorded. Electromyography (EMG) was monitored bilaterally from cranial nerves V VII, IX, X, XI, and XII. Total intravenous anesthesia was used. Neuromuscular blockade was used only for initial intubation. Pre-incision baselines were obtained with good morphology of waveforms. After exposure the floor of the fourth ventricle was mapped by triggered-EMG (t-EMG) using 0.4 to 1.0 mA. In both patients the tumor was entangled with cranial nerves VII to XII on the floor of the fourth ventricle. The surgeon made the decision not to resect the tumor in one case and limited the resection to 70% of the tumor in the second case on the basis of neurophysiological monitoring. This decision was made to minimize any post-operative neurological deficits due to surgical manipulation of the tumor involving the lower cranial nerves. Intraoperative spontaneous and triggered EMG was effectively utilized in preventing injuries to cranial nerves during surgical procedures. All signals remained stable during the surgical procedure. Postoperatively both patients were well with no additional cranial nerve weakness. At three months follow-up, the patients continued to have no deficits.

Effects of voice harmonic complexity on ERP responses to pitch-shifted auditory feedback.

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Behroozmand, Roozbeh; Korzyukov, Oleg; Larson, Charles R

2011-12-01

The present study investigated the neural mechanisms of voice pitch control for different levels of harmonic complexity in the auditory feedback. Event-related potentials (ERPs) were recorded in response to+200 cents pitch perturbations in the auditory feedback of self-produced natural human vocalizations, complex and pure tone stimuli during active vocalization and passive listening conditions. During active vocal production, ERP amplitudes were largest in response to pitch shifts in the natural voice, moderately large for non-voice complex stimuli and smallest for the pure tones. However, during passive listening, neural responses were equally large for pitch shifts in voice and non-voice complex stimuli but still larger than that for pure tones. These findings suggest that pitch change detection is facilitated for spectrally rich sounds such as natural human voice and non-voice complex stimuli compared with pure tones. Vocalization-induced increase in neural responses for voice feedback suggests that sensory processing of naturally-produced complex sounds such as human voice is enhanced by means of motor-driven mechanisms (e.g. efference copies) during vocal production. This enhancement may enable the audio-vocal system to more effectively detect and correct for vocal errors in the feedback of natural human vocalizations to maintain an intended vocal output for speaking. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Cardiac autonomic responses induced by mental tasks and the influence of musical auditory stimulation.

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Barbosa, Juliana Cristina; Guida, Heraldo L; Fontes, Anne M G; Antonio, Ana M S; de Abreu, Luiz Carlos; Barnabé, Viviani; Marcomini, Renata S; Vanderlei, Luiz Carlos M; da Silva, Meire L; Valenti, Vitor E

2014-08-01

We investigated the acute effects of musical auditory stimulation on cardiac autonomic responses to a mental task in 28 healthy men (18-22 years old). In the control protocol (no music), the volunteers remained at seated rest for 10 min and the test was applied for five minutes. After the end of test the subjects remained seated for five more minutes. In the music protocol, the volunteers remained at seated rest for 10 min, then were exposed to music for 10 min; the test was then applied over five minutes, and the subjects remained seated for five more minutes after the test. In the control and music protocols the time domain and frequency domain indices of heart rate variability remained unchanged before, during and after the test. We found that musical auditory stimulation with baroque music did not influence cardiac autonomic responses to the mental task. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cholesterol influences voltage-gated calcium channels and BK-type potassium channels in auditory hair cells.

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Erin K Purcell

Full Text Available The influence of membrane cholesterol content on a variety of ion channel conductances in numerous cell models has been shown, but studies exploring its role in auditory hair cell physiology are scarce. Recent evidence shows that cholesterol depletion affects outer hair cell electromotility and the voltage-gated potassium currents underlying tall hair cell development, but the effects of cholesterol on the major ionic currents governing auditory hair cell excitability are unknown. We investigated the effects of a cholesterol-depleting agent (methyl beta cyclodextrin, MβCD on ion channels necessary for the early stages of sound processing. Large-conductance BK-type potassium channels underlie temporal processing and open in a voltage- and calcium-dependent manner. Voltage-gated calcium channels (VGCCs are responsible for calcium-dependent exocytosis and synaptic transmission to the auditory nerve. Our results demonstrate that cholesterol depletion reduced peak steady-state calcium-sensitive (BK-type potassium current by 50% in chick cochlear hair cells. In contrast, MβCD treatment increased peak inward calcium current (~30%, ruling out loss of calcium channel expression or function as a cause of reduced calcium-sensitive outward current. Changes in maximal conductance indicated a direct impact of cholesterol on channel number or unitary conductance. Immunoblotting following sucrose-gradient ultracentrifugation revealed BK expression in cholesterol-enriched microdomains. Both direct impacts of cholesterol on channel biophysics, as well as channel localization in the membrane, may contribute to the influence of cholesterol on hair cell physiology. Our results reveal a new role for cholesterol in the regulation of auditory calcium and calcium-activated potassium channels and add to the growing evidence that cholesterol is a key determinant in auditory physiology.

Event-related potential response to auditory social stimuli, parent-reported social communicative deficits and autism risk in school-aged children with congenital visual impairment.

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Bathelt, Joe; Dale, Naomi; de Haan, Michelle

2017-10-01

Communication with visual signals, like facial expression, is important in early social development, but the question if these signals are necessary for typical social development remains to be addressed. The potential impact on social development of being born with no or very low levels of vision is therefore of high theoretical and clinical interest. The current study investigated event-related potential responses to basic social stimuli in a rare group of school-aged children with congenital visual disorders of the anterior visual system (globe of the eye, retina, anterior optic nerve). Early-latency event-related potential responses showed no difference between the VI and control group, suggesting similar initial auditory processing. However, the mean amplitude over central and right frontal channels between 280 and 320ms was reduced in response to own-name stimuli, but not control stimuli, in children with VI suggesting differences in social processing. Children with VI also showed an increased rate of autistic-related behaviours, pragmatic language deficits, as well as peer relationship and emotional problems on standard parent questionnaires. These findings suggest that vision may be necessary for the typical development of social processing across modalities. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Loud Music Exposure and Cochlear Synaptopathy in Young Adults: Isolated Auditory Brainstem Response Effects but No Perceptual Consequences.

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Grose, John H; Buss, Emily; Hall, Joseph W

2017-01-01

The purpose of this study was to test the hypothesis that listeners with frequent exposure to loud music exhibit deficits in suprathreshold auditory performance consistent with cochlear synaptopathy. Young adults with normal audiograms were recruited who either did ( n = 31) or did not ( n = 30) have a history of frequent attendance at loud music venues where the typical sound levels could be expected to result in temporary threshold shifts. A test battery was administered that comprised three sets of procedures: (a) electrophysiological tests including distortion product otoacoustic emissions, auditory brainstem responses, envelope following responses, and the acoustic change complex evoked by an interaural phase inversion; (b) psychoacoustic tests including temporal modulation detection, spectral modulation detection, and sensitivity to interaural phase; and (c) speech tests including filtered phoneme recognition and speech-in-noise recognition. The results demonstrated that a history of loud music exposure can lead to a profile of peripheral auditory function that is consistent with an interpretation of cochlear synaptopathy in humans, namely, modestly abnormal auditory brainstem response Wave I/Wave V ratios in the presence of normal distortion product otoacoustic emissions and normal audiometric thresholds. However, there were no other electrophysiological, psychophysical, or speech perception effects. The absence of any behavioral effects in suprathreshold sound processing indicated that, even if cochlear synaptopathy is a valid pathophysiological condition in humans, its perceptual sequelae are either too diffuse or too inconsequential to permit a simple differential diagnosis of hidden hearing loss.

Auditory and visual interhemispheric communication in musicians and non-musicians.

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Rebecca Woelfle

Full Text Available The corpus callosum (CC is a brain structure composed of axon fibres linking the right and left hemispheres. Musical training is associated with larger midsagittal cross-sectional area of the CC, suggesting that interhemispheric communication may be faster in musicians. Here we compared interhemispheric transmission times (ITTs for musicians and non-musicians. ITT was measured by comparing simple reaction times to stimuli presented to the same hemisphere that controlled a button-press response (uncrossed reaction time, or to the contralateral hemisphere (crossed reaction time. Both visual and auditory stimuli were tested. We predicted that the crossed-uncrossed difference (CUD for musicians would be smaller than for non-musicians as a result of faster interhemispheric transfer times. We did not expect a difference in CUDs between the visual and auditory modalities for either musicians or non-musicians, as previous work indicates that interhemispheric transfer may happen through the genu of the CC, which contains motor fibres rather than sensory fibres. There were no significant differences in CUDs between musicians and non-musicians. However, auditory CUDs were significantly smaller than visual CUDs. Although this auditory-visual difference was larger in musicians than non-musicians, the interaction between modality and musical training was not significant. Therefore, although musical training does not significantly affect ITT, the crossing of auditory information between hemispheres appears to be faster than visual information, perhaps because subcortical pathways play a greater role for auditory interhemispheric transfer.

Auditory and visual interhemispheric communication in musicians and non-musicians.

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Woelfle, Rebecca; Grahn, Jessica A

2013-01-01

The corpus callosum (CC) is a brain structure composed of axon fibres linking the right and left hemispheres. Musical training is associated with larger midsagittal cross-sectional area of the CC, suggesting that interhemispheric communication may be faster in musicians. Here we compared interhemispheric transmission times (ITTs) for musicians and non-musicians. ITT was measured by comparing simple reaction times to stimuli presented to the same hemisphere that controlled a button-press response (uncrossed reaction time), or to the contralateral hemisphere (crossed reaction time). Both visual and auditory stimuli were tested. We predicted that the crossed-uncrossed difference (CUD) for musicians would be smaller than for non-musicians as a result of faster interhemispheric transfer times. We did not expect a difference in CUDs between the visual and auditory modalities for either musicians or non-musicians, as previous work indicates that interhemispheric transfer may happen through the genu of the CC, which contains motor fibres rather than sensory fibres. There were no significant differences in CUDs between musicians and non-musicians. However, auditory CUDs were significantly smaller than visual CUDs. Although this auditory-visual difference was larger in musicians than non-musicians, the interaction between modality and musical training was not significant. Therefore, although musical training does not significantly affect ITT, the crossing of auditory information between hemispheres appears to be faster than visual information, perhaps because subcortical pathways play a greater role for auditory interhemispheric transfer.

Auditory-motor learning influences auditory memory for music.

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Brown, Rachel M; Palmer, Caroline

2012-05-01

In two experiments, we investigated how auditory-motor learning influences performers' memory for music. Skilled pianists learned novel melodies in four conditions: auditory only (listening), motor only (performing without sound), strongly coupled auditory-motor (normal performance), and weakly coupled auditory-motor (performing along with auditory recordings). Pianists' recognition of the learned melodies was better following auditory-only or auditory-motor (weakly coupled and strongly coupled) learning than following motor-only learning, and better following strongly coupled auditory-motor learning than following auditory-only learning. Auditory and motor imagery abilities modulated the learning effects: Pianists with high auditory imagery scores had better recognition following motor-only learning, suggesting that auditory imagery compensated for missing auditory feedback at the learning stage. Experiment 2 replicated the findings of Experiment 1 with melodies that contained greater variation in acoustic features. Melodies that were slower and less variable in tempo and intensity were remembered better following weakly coupled auditory-motor learning. These findings suggest that motor learning can aid performers' auditory recognition of music beyond auditory learning alone, and that motor learning is influenced by individual abilities in mental imagery and by variation in acoustic features.

Test-retest reliability of speech-evoked auditory brainstem response in healthy children at a low sensation level.

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Zakaria, Mohd Normani; Jalaei, Bahram

2017-11-01

Auditory brainstem responses evoked by complex stimuli such as speech syllables have been studied in normal subjects and subjects with compromised auditory functions. The stability of speech-evoked auditory brainstem response (speech-ABR) when tested over time has been reported but the literature is limited. The present study was carried out to determine the test-retest reliability of speech-ABR in healthy children at a low sensation level. Seventeen healthy children (6 boys, 11 girls) aged from 5 to 9 years (mean = 6.8 ± 3.3 years) were tested in two sessions separated by a 3-month period. The stimulus used was a 40-ms syllable /da/ presented at 30 dB sensation level. As revealed by pair t-test and intra-class correlation (ICC) analyses, peak latencies, peak amplitudes and composite onset measures of speech-ABR were found to be highly replicable. Compared to other parameters, higher ICC values were noted for peak latencies of speech-ABR. The present study was the first to report the test-retest reliability of speech-ABR recorded at low stimulation levels in healthy children. Due to its good stability, it can be used as an objective indicator for assessing the effectiveness of auditory rehabilitation in hearing-impaired children in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

A Narrow Internal Auditory Canal with Duplication in a Patient with Congenital Sensorineural Hearing Loss

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Baik, Hye Won; Yu, Hye On; Kim, Kyung Soo; Kim, Gi Hyeon [Chung-Ang University Hospital, College of Medicine, Seoul (Korea, Republic of)

2008-07-15

A narrow internal auditory canal (IAC) with duplication is a rare anomaly of the temporal bone. It is associated with congenital sensorineural hearing loss. Aplasia or hypoplasia of the vestibulocochlear nerve may cause the hearing loss. We present an unusual case of an isolated narrow IAC with duplication that was detected by a CT scan. In this case, the IAC was divided by a bony septum into an empty stenotic inferoposterior portion and a large anterosuperior portion containing the facial nerve that was clearly delineated on MRI.

Independent component analysis for cochlear implant artifacts attenuation from electrically evoked auditory steady-state response measurements

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Deprez, Hanne; Gransier, Robin; Hofmann, Michael; van Wieringen, Astrid; Wouters, Jan; Moonen, Marc

2018-02-01

Objective. Electrically evoked auditory steady-state responses (EASSRs) are potentially useful for objective cochlear implant (CI) fitting and follow-up of the auditory maturation in infants and children with a CI. EASSRs are recorded in the electro-encephalogram (EEG) in response to electrical stimulation with continuous pulse trains, and are distorted by significant CI artifacts related to this electrical stimulation. The aim of this study is to evaluate a CI artifacts attenuation method based on independent component analysis (ICA) for three EASSR datasets. Approach. ICA has often been used to remove CI artifacts from the EEG to record transient auditory responses, such as cortical evoked auditory potentials. Independent components (ICs) corresponding to CI artifacts are then often manually identified. In this study, an ICA based CI artifacts attenuation method was developed and evaluated for EASSR measurements with varying CI artifacts and EASSR characteristics. Artifactual ICs were automatically identified based on their spectrum. Main results. For 40 Hz amplitude modulation (AM) stimulation at comfort level, in high SNR recordings, ICA succeeded in removing CI artifacts from all recording channels, without distorting the EASSR. For lower SNR recordings, with 40 Hz AM stimulation at lower levels, or 90 Hz AM stimulation, ICA either distorted the EASSR or could not remove all CI artifacts in most subjects, except for two of the seven subjects tested with low level 40 Hz AM stimulation. Noise levels were reduced after ICA was applied, and up to 29 ICs were rejected, suggesting poor ICA separation quality. Significance. We hypothesize that ICA is capable of separating CI artifacts and EASSR in case the contralateral hemisphere is EASSR dominated. For small EASSRs or large CI artifact amplitudes, ICA separation quality is insufficient to ensure complete CI artifacts attenuation without EASSR distortion.

Speaking Two Languages Enhances an Auditory but Not a Visual Neural Marker of Cognitive Inhibition

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Mercedes Fernandez

2014-09-01

Full Text Available The purpose of the present study was to replicate and extend our original findings of enhanced neural inhibitory control in bilinguals. We compared English monolinguals to Spanish/English bilinguals on a non-linguistic, auditory Go/NoGo task while recording event-related brain potentials. New to this study was the visual Go/NoGo task, which we included to investigate whether enhanced neural inhibition in bilinguals extends from the auditory to the visual modality. Results confirmed our original findings and revealed greater inhibition in bilinguals compared to monolinguals. As predicted, compared to monolinguals, bilinguals showed increased N2 amplitude during the auditory NoGo trials, which required inhibitory control, but no differences during the Go trials, which required a behavioral response and no inhibition. Interestingly, during the visual Go/NoGo task, event related brain potentials did not distinguish the two groups, and behavioral responses were similar between the groups regardless of task modality. Thus, only auditory trials that required inhibitory control revealed between-group differences indicative of greater neural inhibition in bilinguals. These results show that experience-dependent neural changes associated with bilingualism are specific to the auditory modality and that the N2 event-related brain potential is a sensitive marker of this plasticity.

Visual Information Present in Infragranular Layers of Mouse Auditory Cortex.

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Morrill, Ryan J; Hasenstaub, Andrea R

2018-03-14

The cerebral cortex is a major hub for the convergence and integration of signals from across the sensory modalities; sensory cortices, including primary regions, are no exception. Here we show that visual stimuli influence neural firing in the auditory cortex of awake male and female mice, using multisite probes to sample single units across multiple cortical layers. We demonstrate that visual stimuli influence firing in both primary and secondary auditory cortex. We then determine the laminar location of recording sites through electrode track tracing with fluorescent dye and optogenetic identification using layer-specific markers. Spiking responses to visual stimulation occur deep in auditory cortex and are particularly prominent in layer 6. Visual modulation of firing rate occurs more frequently at areas with secondary-like auditory responses than those with primary-like responses. Auditory cortical responses to drifting visual gratings are not orientation-tuned, unlike visual cortex responses. The deepest cortical layers thus appear to be an important locus for cross-modal integration in auditory cortex. SIGNIFICANCE STATEMENT The deepest layers of the auditory cortex are often considered its most enigmatic, possessing a wide range of cell morphologies and atypical sensory responses. Here we show that, in mouse auditory cortex, these layers represent a locus of cross-modal convergence, containing many units responsive to visual stimuli. Our results suggest that this visual signal conveys the presence and timing of a stimulus rather than specifics about that stimulus, such as its orientation. These results shed light on both how and what types of cross-modal information is integrated at the earliest stages of sensory cortical processing. Copyright © 2018 the authors 0270-6474/18/382854-09$15.00/0.

Identification and prediction of diabetic sensorimotor polyneuropathy using individual and simple combinations of nerve conduction study parameters.

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Alanna Weisman

Full Text Available OBJECTIVE: Evaluation of diabetic sensorimotor polyneuropathy (DSP is hindered by the need for complex nerve conduction study (NCS protocols and lack of predictive biomarkers. We aimed to determine the performance of single and simple combinations of NCS parameters for identification and future prediction of DSP. MATERIALS AND METHODS: 406 participants (61 with type 1 diabetes and 345 with type 2 diabetes with a broad spectrum of neuropathy, from none to severe, underwent NCS to determine presence or absence of DSP for cross-sectional (concurrent validity analysis. The 109 participants without baseline DSP were re-evaluated for its future onset (predictive validity. Performance of NCS parameters was compared by area under the receiver operating characteristic curve (AROC. RESULTS: At baseline there were 246 (60% Prevalent Cases. After 3.9 years mean follow-up, 25 (23% of the 109 Prevalent Controls that were followed became Incident DSP Cases. Threshold values for peroneal conduction velocity and sural amplitude potential best identified Prevalent Cases (AROC 0.90 and 0.83, sensitivity 80 and 83%, specificity 89 and 72%, respectively. Baseline tibial F-wave latency, peroneal conduction velocity and the sum of three lower limb nerve conduction velocities (sural, peroneal, and tibial best predicted 4-year incidence (AROC 0.79, 0.79, and 0.85; sensitivity 79, 70, and 81%; specificity 63, 74 and 77%, respectively. DISCUSSION: Individual NCS parameters or their simple combinations are valid measures for identification and future prediction of DSP. Further research into the predictive roles of tibial F-wave latencies, peroneal conduction velocity, and sum of conduction velocities as markers of incipient nerve injury is needed to risk-stratify individuals for clinical and research protocols.

The auditory enhancement effect is not reflected in the 80-Hz auditory steady-state response.

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Carcagno, Samuele; Plack, Christopher J; Portron, Arthur; Semal, Catherine; Demany, Laurent

2014-08-01

The perceptual salience of a target tone presented in a multitone background is increased by the presentation of a precursor sound consisting of the multitone background alone. It has been proposed that this "enhancement" phenomenon results from an effective amplification of the neural response to the target tone. In this study, we tested this hypothesis in humans, by comparing the auditory steady-state response (ASSR) to a target tone that was enhanced by a precursor sound with the ASSR to a target tone that was not enhanced. In order to record neural responses originating in the brainstem, the ASSR was elicited by amplitude modulating the target tone at a frequency close to 80 Hz. The results did not show evidence of an amplified neural response to enhanced tones. In a control condition, we measured the ASSR to a target tone that, instead of being perceptually enhanced by a precursor sound, was acoustically increased in level. This level increase matched the magnitude of enhancement estimated psychophysically with a forward masking paradigm in a previous experimental phase. We found that the ASSR to the tone acoustically increased in level was significantly greater than the ASSR to the tone enhanced by the precursor sound. Overall, our results suggest that the enhancement effect cannot be explained by an amplified neural response at the level of the brainstem. However, an alternative possibility is that brainstem neurons with enhanced responses do not contribute to the scalp-recorded ASSR.

Frequency- and amplitude-transitioned waveforms mitigate the onset response in high-frequency nerve block

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Gerges, Meana; Foldes, Emily L.; Ackermann, D. Michael; Bhadra, Narendra; Bhadra, Niloy; Kilgore, Kevin L.

2010-12-01

High-frequency alternating currents (HFAC) have proven to be a reversible and rapid method of blocking peripheral nerve conduction, holding promise for treatment of disorders associated with undesirable neuronal activity. The delivery of HFAC is characterized by a transient period of neural firing at its inception, termed the 'onset response'. The onset response is minimized for higher frequencies and higher amplitudes, but requires larger currents. However, the complete block can be maintained at lower frequencies and amplitudes, using lower currents. In this in vivo study on whole mammalian peripheral nerves, we demonstrate a method to minimize the onset response by initiating the block using a stimulation paradigm with a high frequency and large amplitude, and then transitioning to a low-frequency and low-amplitude waveform, reducing the currents required to maintain the conduction block. In five of six animals, it was possible to transition from a 30 kHz to a 10 kHz waveform without inducing any transient neural firing. The minimum transition time was 0.03 s. Transition activity was minimized or eliminated with longer transition times. The results of this study show that this method is feasible for achieving a nerve block with minimal onset responses and current amplitude requirements.

Reliability, reference values and predictor variables of the ulnar sensory nerve in disease free adults.

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Ruediger, T M; Allison, S C; Moore, J M; Wainner, R S

2014-09-01

The purposes of this descriptive and exploratory study were to examine electrophysiological measures of ulnar sensory nerve function in disease free adults to determine reliability, determine reference values computed with appropriate statistical methods, and examine predictive ability of anthropometric variables. Antidromic sensory nerve conduction studies of the ulnar nerve using surface electrodes were performed on 100 volunteers. Reference values were computed from optimally transformed data. Reliability was computed from 30 subjects. Multiple linear regression models were constructed from four predictor variables. Reliability was greater than 0.85 for all paired measures. Responses were elicited in all subjects; reference values for sensory nerve action potential (SNAP) amplitude from above elbow stimulation are 3.3 μV and decrement across-elbow less than 46%. No single predictor variable accounted for more than 15% of the variance in the response. Electrophysiologic measures of the ulnar sensory nerve are reliable. Absent SNAP responses are inconsistent with disease free individuals. Reference values recommended in this report are based on appropriate transformations of non-normally distributed data. No strong statistical model of prediction could be derived from the limited set of predictor variables. Reliability analyses combined with relatively low level of measurement error suggest that ulnar sensory reference values may be used with confidence. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Non-Monotonic Relation Between Noise Exposure Severity and Neuronal Hyperactivity in the Auditory Midbrain

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Lara Li Hesse

2016-08-01

Full Text Available The occurrence of tinnitus can be linked to hearing loss in the majority of cases, but there is nevertheless a large degree of unexplained heterogeneity in the relation between hearing loss and tinnitus. Part of the problem might be that hearing loss is usually quantified in terms of increased hearing thresholds, which only provides limited information about the underlying cochlear damage. Moreover, noise exposure that does not cause hearing threshold loss can still lead to hidden hearing loss (HHL, i.e. functional deafferentation of auditory nerve fibres (ANFs through loss of synaptic ribbons in inner hair cells. Whilst it is known that increased hearing thresholds can trigger increases in spontaneous neural activity in the central auditory system, i.e. a putative neural correlate of tinnitus, the central effects of HHL have not yet been investigated. Here, we exposed mice to octave-band noise at 100 and 105 dB SPL, to generate HHL and permanent increases of hearing thresholds, respectively. Deafferentation of ANFs was confirmed through measurement of auditory brainstem responses and cochlear immunohistochemistry. Acute extracellular recordings from the auditory midbrain (inferior colliculus demonstrated increases in spontaneous neuronal activity (a putative neural correlate of tinnitus in both groups. Surprisingly the increase in spontaneous activity was most pronounced in the mice with HHL, suggesting that the relation between hearing loss and neuronal hyperactivity might be more complex than currently understood. Our computational model indicated that these differences in neuronal hyperactivity could arise from different degrees of deafferentation of low-threshold ANFs in the two exposure groups.Our results demonstrate that HHL is sufficient to induce changes in central auditory processing, and they also indicate a non-monotonic relationship between cochlear damage and neuronal hyperactivity, suggesting an explanation for why tinnitus might

Detection of the symptomatic nerve root

International Nuclear Information System (INIS)

Toyone, Tomoaki; Takahashi, Kazuhisa; Yamagata, Masayasu

1993-01-01

Twenty-five patients with lumbar disc herniation with a chief complaint of unilateral leg pain underwent gadolinium-DTPA enhanced MRI, particularly to examine the nerve root in the distal area of hernia. MRI appearance fell into three grades: 0 - no visualization (n=7), 1 - heterogeneous visualization (n=7), and 2 - homogeneous visualization (n=10). In the quantitative evaluation of the severity of sciatica using SLR and JOA scores, it was found to be associated with the degree of visualization. All patients of grade 2 were required to receive surgery because pain relief was not attained in spite of 3 months or more conservative treatment. These findings indicatd the usefulness of MRI in predicting prognosis, as well as in diagnosing the responsible level. Since blood-nerve barrier damage and intraneural edema are considered to be involved in the visualization of the nerve root on MRI, MRI will help in diagnosing radicular sciatica and elucidating the pathophysiology of the disease. (N.K.)

Binaural interaction in the auditory brainstem response: a normative study.

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Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Battmer, Rolf-Dieter; Dhooge, Ingeborg J M

2015-04-01

Binaural interaction can be investigated using auditory evoked potentials. A binaural interaction component can be derived from the auditory brainstem response (ABR-BIC) and is considered evidence for binaural interaction at the level of the brainstem. Although click ABR-BIC has been investigated thoroughly, data on 500 Hz tone-burst (TB) ABR-BICs are scarce. In this study, characteristics of click and 500 Hz TB ABR-BICs are described. Furthermore, reliability of both click and 500 Hz TB ABR-BIC are investigated. Eighteen normal hearing young adults (eight women, ten men) were included. ABRs were recorded in response to clicks and 500 Hz TBs. ABR-BICs were derived by subtracting the binaural response from the sum of the monaural responses measured in opposite ears. Good inter-rater reliability is obtained for both click and 500 Hz TB ABR-BICs. The most reliable peak in click ABR-BIC occurs at a mean latency of 6.06 ms (SD 0.354 ms). Reliable 500 Hz TB ABR-BIC are obtained with a mean latency of 9.47 ms (SD 0.678 ms). Amplitudes are larger for 500 Hz TB ABR-BIC than for clicks. The most reliable peak in click ABR-BIC occurs at the downslope of wave V. Five hundred Hertz TB ABR-BIC is characterized by a broad positivity occurring at the level of wave V. The ABR-BIC is a useful technique to investigate binaural interaction in certain populations. Examples are bilateral hearing aid users, bilateral cochlear implant users and bimodal listeners. The latter refers to the combination of unilateral cochlear implantation and contralateral residual hearing. The majority of these patients have residual hearing in the low frequencies. The current study suggests that 500 Hz TB ABR-BIC may be a suitable technique to assess binaural interaction in this specific population of cochlear implant users. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Mouse Panx1 Is Dispensable for Hearing Acquisition and Auditory Function.

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Zorzi, Veronica; Paciello, Fabiola; Ziraldo, Gaia; Peres, Chiara; Mazzarda, Flavia; Nardin, Chiara; Pasquini, Miriam; Chiani, Francesco; Raspa, Marcello; Scavizzi, Ferdinando; Carrer, Andrea; Crispino, Giulia; Ciubotaru, Catalin D; Monyer, Hannah; Fetoni, Anna R; M Salvatore, Anna; Mammano, Fabio

2017-01-01

Panx1 forms plasma membrane channels in brain and several other organs, including the inner ear. Biophysical properties, activation mechanisms and modulators of Panx1 channels have been characterized in detail, however the impact of Panx1 on auditory function is unclear due to conflicts in published results. To address this issue, hearing performance and cochlear function of the Panx1 -/- mouse strain, the first with a reported global ablation of Panx1 , were scrutinized. Male and female homozygous ( Panx1 -/-), hemizygous ( Panx1 +/-) and their wild type (WT) siblings ( Panx1 +/+) were used for this study. Successful ablation of Panx1 was confirmed by RT-PCR and Western immunoblotting in the cochlea and brain of Panx1 -/- mice. Furthermore, a previously validated Panx1-selective antibody revealed strong immunoreactivity in WT but not in Panx1 -/- cochleae. Hearing sensitivity, outer hair cell-based "cochlear amplifier" and cochlear nerve function, analyzed by auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) recordings, were normal in Panx1 +/- and Panx1 -/- mice. In addition, we determined that global deletion of Panx1 impacts neither on connexin expression, nor on gap-junction coupling in the developing organ of Corti. Finally, spontaneous intercellular Ca 2+ signal (ICS) activity in organotypic cochlear cultures, which is key to postnatal development of the organ of Corti and essential for hearing acquisition, was not affected by Panx1 ablation. Therefore, our results provide strong evidence that, in mice, Panx1 is dispensable for hearing acquisition and auditory function.

The right hemisphere supports but does not replace left hemisphere auditory function in patients with persisting aphasia.

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Teki, Sundeep; Barnes, Gareth R; Penny, William D; Iverson, Paul; Woodhead, Zoe V J; Griffiths, Timothy D; Leff, Alexander P

2013-06-01

In this study, we used magnetoencephalography and a mismatch paradigm to investigate speech processing in stroke patients with auditory comprehension deficits and age-matched control subjects. We probed connectivity within and between the two temporal lobes in response to phonemic (different word) and acoustic (same word) oddballs using dynamic causal modelling. We found stronger modulation of self-connections as a function of phonemic differences for control subjects versus aphasics in left primary auditory cortex and bilateral superior temporal gyrus. The patients showed stronger modulation of connections from right primary auditory cortex to right superior temporal gyrus (feed-forward) and from left primary auditory cortex to right primary auditory cortex (interhemispheric). This differential connectivity can be explained on the basis of a predictive coding theory which suggests increased prediction error and decreased sensitivity to phonemic boundaries in the aphasics' speech network in both hemispheres. Within the aphasics, we also found behavioural correlates with connection strengths: a negative correlation between phonemic perception and an inter-hemispheric connection (left superior temporal gyrus to right superior temporal gyrus), and positive correlation between semantic performance and a feedback connection (right superior temporal gyrus to right primary auditory cortex). Our results suggest that aphasics with impaired speech comprehension have less veridical speech representations in both temporal lobes, and rely more on the right hemisphere auditory regions, particularly right superior temporal gyrus, for processing speech. Despite this presumed compensatory shift in network connectivity, the patients remain significantly impaired.

Intraoperative Neural Response Telemetry and Neural Recovery Function: a Comparative Study between Adults and Children

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Carvalho, Bettina

2014-04-01

Full Text Available Introduction Neural response telemetry (NRT is a method of capturing the action potential of the distal portion of the auditory nerve in cochlear implant (CI users, using the CI itself to elicit and record the answers. In addition, it can also measure the recovery function of the auditory nerve (REC, that is, the refractory properties of the nerve. It is not clear in the literature whether the responses from adults are the same as those from children. Objective To compare the results of NRT and REC between adults and children undergoing CI surgery. Methods Cross-sectional, descriptive, and retrospective study of the results of NRT and REC for patients undergoing IC at our service. The NRT is assessed by the level of amplitude (microvolts and REC as a function of three parameters: A (saturation level, in microvolts, t0 (absolute refractory period, in seconds, and tau (curve of the model function, measured in three electrodes (apical, medial, and basal. Results Fifty-two patients were evaluated with intraoperative NRT (26 adults and 26 children, and 24 with REC (12 adults and 12 children. No statistically significant difference was found between intraoperative responses of adults and children for NRT or for REC's three parameters, except for parameter A of the basal electrode. Conclusion The results of intraoperative NRT and REC were not different between adults and children, except for parameter A of the basal electrode.

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

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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. �

Inter- and intrapatient variability of facial nerve response areas in the floor of the fourth ventricle.

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Bertalanffy, Helmut; Tissira, Nadir; Krayenbühl, Niklaus; Bozinov, Oliver; Sarnthein, Johannes

2011-03-01

Surgical exposure of intrinsic brainstem lesions through the floor of the 4th ventricle requires precise identification of facial nerve (CN VII) fibers to avoid damage. To assess the shape, size, and variability of the area where the facial nerve can be stimulated electrophysiologically on the surface of the rhomboid fossa. Over a period of 18 months, 20 patients were operated on for various brainstem and/or cerebellar lesions. Facial nerve fibers were stimulated to yield compound muscle action potentials (CMAP) in the target muscles. Using the sites of CMAP yield, a detailed functional map of the rhomboid fossa was constructed for each patient. Lesions resected included 14 gliomas, 5 cavernomas, and 1 epidermoid cyst. Of 40 response areas mapped, 19 reached the median sulcus. The distance from the obex to the caudal border of the response area ranged from 8 to 27 mm (median, 17 mm). The rostrocaudal length of the response area ranged from 2 to 15 mm (median, 5 mm). Facial nerve response areas showed large variability in size and position, even in patients with significant distance between the facial colliculus and underlying pathological lesion. Lesions located close to the facial colliculus markedly distorted the response area. This is the first documentation of variability in the CN VII response area in the rhomboid fossa. Knowledge of this remarkable variability may facilitate the assessment of safe entry zones to the brainstem and may contribute to improved outcome following neurosurgical interventions within this sensitive area of the brain.

Fetal alcohol exposure reduces responsiveness of taste nerves and trigeminal chemosensory neurons to ethanol and its flavor components.

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Glendinning, John I; Tang, Joyce; Morales Allende, Ana Paula; Bryant, Bruce P; Youngentob, Lisa; Youngentob, Steven L

2017-08-01

Fetal alcohol exposure (FAE) leads to increased intake of ethanol in adolescent rats and humans. We asked whether these behavioral changes may be mediated in part by changes in responsiveness of the peripheral taste and oral trigeminal systems. We exposed the experimental rats to ethanol in utero by administering ethanol to dams through a liquid diet; we exposed the control rats to an isocaloric and isonutritive liquid diet. To assess taste responsiveness, we recorded responses of the chorda tympani (CT) and glossopharyngeal (GL) nerves to lingual stimulation with ethanol, quinine, sucrose, and NaCl. To assess trigeminal responsiveness, we measured changes in calcium levels of isolated trigeminal ganglion (TG) neurons during stimulation with ethanol, capsaicin, mustard oil, and KCl. Compared with adolescent control rats, the adolescent experimental rats exhibited diminished CT nerve responses to ethanol, quinine, and sucrose and GL nerve responses to quinine and sucrose. The reductions in taste responsiveness persisted into adulthood for quinine but not for any of the other stimuli. Adolescent experimental rats also exhibited reduced TG neuron responses to ethanol, capsaicin, and mustard oil. The lack of change in responsiveness of the taste nerves to NaCl and the TG neurons to KCl indicates that FAE altered only a subset of the response pathways within each chemosensory system. We propose that FAE reprograms development of the peripheral taste and trigeminal systems in ways that reduce their responsiveness to ethanol and surrogates for its pleasant (i.e., sweet) and unpleasant (i.e., bitterness, oral burning) flavor attributes. NEW & NOTEWORTHY Pregnant mothers are advised to avoid alcohol. This is because even small amounts of alcohol can alter fetal brain development and increase the risk of adolescent alcohol abuse. We asked how fetal alcohol exposure (FAE) produces the latter effect in adolescent rats by measuring responsiveness of taste nerves and trigeminal

Auditory Attention and Comprehension During a Simulated Night Shift: Effects of Task Characteristics.

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Pilcher, June J; Jennings, Kristen S; Phillips, Ginger E; McCubbin, James A

2016-11-01

The current study investigated performance on a dual auditory task during a simulated night shift. Night shifts and sleep deprivation negatively affect performance on vigilance-based tasks, but less is known about the effects on complex tasks. Because language processing is necessary for successful work performance, it is important to understand how it is affected by night work and sleep deprivation. Sixty-two participants completed a simulated night shift resulting in 28 hr of total sleep deprivation. Performance on a vigilance task and a dual auditory language task was examined across four testing sessions. The results indicate that working at night negatively impacts vigilance, auditory attention, and comprehension. The effects on the auditory task varied based on the content of the auditory material. When the material was interesting and easy, the participants performed better. Night work had a greater negative effect when the auditory material was less interesting and more difficult. These findings support research that vigilance decreases during the night. The results suggest that auditory comprehension suffers when individuals are required to work at night. Maintaining attention and controlling effort especially on passages that are less interesting or more difficult could improve performance during night shifts. The results from the current study apply to many work environments where decision making is necessary in response to complex auditory information. Better predicting the effects of night work on language processing is important for developing improved means of coping with shiftwork. © 2016, Human Factors and Ergonomics Society.

Cortical processing of pitch: Model-based encoding and decoding of auditory fMRI responses to real-life sounds.

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De Angelis, Vittoria; De Martino, Federico; Moerel, Michelle; Santoro, Roberta; Hausfeld, Lars; Formisano, Elia

2017-11-13

Pitch is a perceptual attribute related to the fundamental frequency (or periodicity) of a sound. So far, the cortical processing of pitch has been investigated mostly using synthetic sounds. However, the complex harmonic structure of natural sounds may require different mechanisms for the extraction and analysis of pitch. This study investigated the neural representation of pitch in human auditory cortex using model-based encoding and decoding analyses of high field (7 T) functional magnetic resonance imaging (fMRI) data collected while participants listened to a wide range of real-life sounds. Specifically, we modeled the fMRI responses as a function of the sounds' perceived pitch height and salience (related to the fundamental frequency and the harmonic structure respectively), which we estimated with a computational algorithm of pitch extraction (de Cheveigné and Kawahara, 2002). First, using single-voxel fMRI encoding, we identified a pitch-coding region in the antero-lateral Heschl's gyrus (HG) and adjacent superior temporal gyrus (STG). In these regions, the pitch representation model combining height and salience predicted the fMRI responses comparatively better than other models of acoustic processing and, in the right hemisphere, better than pitch representations based on height/salience alone. Second, we assessed with model-based decoding that multi-voxel response patterns of the identified regions are more informative of perceived pitch than the remainder of the auditory cortex. Further multivariate analyses showed that complementing a multi-resolution spectro-temporal sound representation with pitch produces a small but significant improvement to the decoding of complex sounds from fMRI response patterns. In sum, this work extends model-based fMRI encoding and decoding methods - previously employed to examine the representation and processing of acoustic sound features in the human auditory system - to the representation and processing of a relevant

Congenital Deafness Reduces, But Does Not Eliminate Auditory Responsiveness in Cat Extrastriate Visual Cortex.

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Land, Rüdiger; Radecke, Jan-Ole; Kral, Andrej

2018-04-01

Congenital deafness not only affects the development of the auditory cortex, but also the interrelation between the visual and auditory system. For example, congenital deafness leads to visual modulation of the deaf auditory cortex in the form of cross-modal plasticity. Here we asked, whether congenital deafness additionally affects auditory modulation in the visual cortex. We demonstrate that auditory activity, which is normally present in the lateral suprasylvian visual areas in normal hearing cats, can also be elicited by electrical activation of the auditory system with cochlear implants. We then show that in adult congenitally deaf cats auditory activity in this region was reduced when tested with cochlear implant stimulation. However, the change in this area was small and auditory activity was not completely abolished despite years of congenital deafness. The results document that congenital deafness leads not only to changes in the auditory cortex but also affects auditory modulation of visual areas. However, the results further show a persistence of fundamental cortical sensory functional organization despite congenital deafness. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Ephaptic coupling of myelinated nerve fibers

DEFF Research Database (Denmark)

Binczak, S.; Eilbeck, J. C.; Scott, Alwyn C.

2001-01-01

Numerical predictions of a simple myelinated nerve fiber model are compared with theoretical results in the continuum and discrete limits, clarifying the nature of the conduction process on an isolated nerve axon. Since myelinated nerve fibers are often arranged in bundles, this model is used...

Mechanisms underlying electrical and mechanical responses of the bovine retractor penis to inhibitory nerve stimulation and to an inhibitory extract.

Science.gov (United States)

Byrne, N. G.; Muir, T. C.

1985-01-01

The response of the bovine retractor penis (BRP) to stimulation of non-adrenergic, non-cholinergic (NANC) inhibitory nerves and to an inhibitory extract prepared from this muscle have been studied using intracellular microelectrode, sucrose gap and conventional mechanical recording techniques. Both inhibitory nerve stimulation and inhibitory extract hyperpolarized the membrane potential and relaxed spontaneous or guanethidine (3 X 10(-5) M)-induced tone. These effects were accompanied by an increase in membrane resistance. Following membrane potential displacement from an average value of -53 +/- 7 mV (n = 184; Byrne & Muir, 1984) inhibitory potentials to nerve stimulation were abolished at approximately -30 mV; there was no evidence of reversal. Displacement by inward hyperpolarizing current over the range -45 to -60 mV increased the inhibitory response to nerve stimulation and to inhibitory extract; at more negative potential values (above approximately -60 mV) the inhibitory potential decreased and was abolished (approximately -103 mV). There was no evidence of reversal. Removal of [K+]o reversibly reduced hyperpolarization to nerve stimulation and inhibitory extract. No enhancement was observed. Increasing the [K+]o to 20 mM reduced the inhibitory potential to nerve stimulation but this was restored by passive membrane hyperpolarization. Inhibitory potentials were obtained at membrane potential values exceeding that of the estimated EK (-49 mV). [Cl-]o-free or [Cl-]o-deficient solutions reduced and abolished (after some 20-25 min) the hyperpolarization produced by inhibitory nerve stimulation or inhibitory extract. The inhibitory potential amplitude following nerve stimulation was not restored by passive displacement of the membrane potential from -26 to -104 mV approximately. Ouabain (1-5 X 10(-5) M) reduced then (45-60 min later) abolished the inhibitory potential to nerve stimulation. The effects of this drug on the extract were not investigated. It is

Exploring vocal recovery after cranial nerve injury in Bengalese finches.

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Urbano, Catherine M; Peterson, Jennifer R; Cooper, Brenton G

2013-02-08

Songbirds and humans use auditory feedback to acquire and maintain their vocalizations. The Bengalese finch (Lonchura striata domestica) is a songbird species that rapidly modifies its vocal output to adhere to an internal song memory. In this species, the left side of the bipartite vocal organ is specialized for producing louder, higher frequencies (≥2.2kHz) and denervation of the left vocal muscles eliminates these notes. Thus, the return of higher frequency notes after cranial nerve injury can be used as a measure of vocal recovery. Either the left or right side of the syrinx was denervated by resection of the tracheosyringeal portion of the hypoglossal nerve. Histologic analyses of syringeal muscle tissue showed significant muscle atrophy in the denervated side. After left nerve resection, songs were mainly composed of lower frequency syllables, but three out of five birds recovered higher frequency syllables. Right nerve resection minimally affected phonology, but it did change song syntax; syllable sequence became abnormally stereotyped after right nerve resection. Therefore, damage to the neuromuscular control of sound production resulted in reduced motor variability, and Bengalese finches are a potential model for functional vocal recovery following cranial nerve injury. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Reduced auditory efferent activity in childhood selective mutism.

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Bar-Haim, Yair; Henkin, Yael; Ari-Even-Roth, Daphne; Tetin-Schneider, Simona; Hildesheimer, Minka; Muchnik, Chava

2004-06-01

Selective mutism is a psychiatric disorder of childhood characterized by consistent inability to speak in specific situations despite the ability to speak normally in others. The objective of this study was to test whether reduced auditory efferent activity, which may have direct bearings on speaking behavior, is compromised in selectively mute children. Participants were 16 children with selective mutism and 16 normally developing control children matched for age and gender. All children were tested for pure-tone audiometry, speech reception thresholds, speech discrimination, middle-ear acoustic reflex thresholds and decay function, transient evoked otoacoustic emission, suppression of transient evoked otoacoustic emission, and auditory brainstem response. Compared with control children, selectively mute children displayed specific deficiencies in auditory efferent activity. These aberrations in efferent activity appear along with normal pure-tone and speech audiometry and normal brainstem transmission as indicated by auditory brainstem response latencies. The diminished auditory efferent activity detected in some children with SM may result in desensitization of their auditory pathways by self-vocalization and in reduced control of masking and distortion of incoming speech sounds. These children may gradually learn to restrict vocalization to the minimal amount possible in contexts that require complex auditory processing.

The effects of divided attention on auditory priming.

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Mulligan, Neil W; Duke, Marquinn; Cooper, Angela W

2007-09-01

Traditional theorizing stresses the importance of attentional state during encoding for later memory, based primarily on research with explicit memory. Recent research has begun to investigate the role of attention in implicit memory but has focused almost exclusively on priming in the visual modality. The present experiments examined the effect of divided attention on auditory implicit memory, using auditory perceptual identification, word-stem completion and word-fragment completion. Participants heard study words under full attention conditions or while simultaneously carrying out a distractor task (the divided attention condition). In Experiment 1, a distractor task with low response frequency failed to disrupt later auditory priming (but diminished explicit memory as assessed with auditory recognition). In Experiment 2, a distractor task with greater response frequency disrupted priming on all three of the auditory priming tasks as well as the explicit test. These results imply that although auditory priming is less reliant on attention than explicit memory, it is still greatly affected by at least some divided-attention manipulations. These results are consistent with research using visual priming tasks and have relevance for hypotheses regarding attention and auditory priming.

Prepulse inhibition of auditory change-related cortical responses

Directory of Open Access Journals (Sweden)

Inui Koji

2012-10-01

Full Text Available Abstract Background Prepulse inhibition (PPI of the startle response is an important tool to investigate the biology of schizophrenia. PPI is usually observed by use of a startle reflex such as blinking following an intense sound. A similar phenomenon has not been reported for cortical responses. Results In 12 healthy subjects, change-related cortical activity in response to an abrupt increase of sound pressure by 5 dB above the background of 65 dB SPL (test stimulus was measured using magnetoencephalography. The test stimulus evoked a clear cortical response peaking at around 130 ms (Change-N1m. In Experiment 1, effects of the intensity of a prepulse (0.5 ~ 5 dB on the test response were examined using a paired stimulation paradigm. In Experiment 2, effects of the interval between the prepulse and test stimulus were examined using interstimulus intervals (ISIs of 50 ~ 350 ms. When the test stimulus was preceded by the prepulse, the Change-N1m was more strongly inhibited by a stronger prepulse (Experiment 1 and a shorter ISI prepulse (Experiment 2. In addition, the amplitude of the test Change-N1m correlated positively with both the amplitude of the prepulse-evoked response and the degree of inhibition, suggesting that subjects who are more sensitive to the auditory change are more strongly inhibited by the prepulse. Conclusions Since Change-N1m is easy to measure and control, it would be a valuable tool to investigate mechanisms of sensory gating or the biology of certain mental diseases such as schizophrenia.

Magnetic resonance imaging of facial nerve schwannoma.

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Thompson, Andrew L; Aviv, Richard I; Chen, Joseph M; Nedzelski, Julian M; Yuen, Heng-Wai; Fox, Allan J; Bharatha, Aditya; Bartlett, Eric S; Symons, Sean P

2009-12-01

This study characterizes the magnetic resonance (MR) appearances of facial nerve schwannoma (FNS). We hypothesize that the extent of FNS demonstrated on MR will be greater compared to prior computed tomography studies, that geniculate involvement will be most common, and that cerebellar pontine angle (CPA) and internal auditory canal (IAC) involvement will more frequently result in sensorineural hearing loss (SNHL). Retrospective study. Clinical, pathologic, and enhanced MR imaging records of 30 patients with FNS were analyzed. Morphologic characteristics and extent of segmental facial nerve involvement were documented. Median age at initial imaging was 51 years (range, 28-76 years). Pathologic confirmation was obtained in 14 patients (47%), and the diagnosis reached in the remainder by identification of a mass, thickening, and enhancement along the course of the facial nerve. All 30 lesions involved two or more contiguous segments of the facial nerve, with 28 (93%) involving three or more segments. The median segments involved per lesion was 4, mean of 3.83. Geniculate involvement was most common, in 29 patients (97%). CPA (P = .001) and IAC (P = .02) involvement was significantly related to SNHL. Seventeen patients (57%) presented with facial nerve dysfunction, manifesting in 12 patients as facial nerve weakness or paralysis, and/or in eight with involuntary movements of the facial musculature. This study highlights the morphologic heterogeneity and typical multisegment involvement of FNS. Enhanced MR is the imaging modality of choice for FNS. The neuroradiologist must accurately diagnose and characterize this lesion, and thus facilitate optimal preoperative planning and counseling.

Labyrinthine Artery Aneurysm as an Internal Auditory Canal Mass

OpenAIRE

Diaz, Rodney C.; Konia, Thomas; Brunberg, James

2013-01-01

We present the first case report of a labyrinthine artery aneurysm masquerading as an internal auditory canal tumor. A 72-year-old woman presented with sudden onset right facial paralysis, facial pain, hearing loss, and vertigo. She demonstrated dense right-sided facial paralysis involving all branches of the facial nerve, left beating horizontal nystagmus, and anacusis of the right ear. Magnetic resonance imaging with contrast demonstrated a 6 × 7 mm peripherally enhancing lesion with lack o...

Comparison of Auditory Brainstem Response in Noise Induced Tinnitus and Non-Tinnitus Control Subjects

Directory of Open Access Journals (Sweden)

Ghassem Mohammadkhani

2009-12-01

Full Text Available Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR were compared in noise induced tinnitus and non-tinnitus control subjects.Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.Results: Mean interpeak latencies of III-V (p= 0.022, I-V (p=0.033 in ipsilatral electrode array and mean absolute latencies of IV (p=0.015 and V (p=0.048 in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group. Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

Impairments in musical abilities reflected in the auditory brainstem: evidence from congenital amusia.

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Lehmann, Alexandre; Skoe, Erika; Moreau, Patricia; Peretz, Isabelle; Kraus, Nina

2015-07-01

Congenital amusia is a neurogenetic condition, characterized by a deficit in music perception and production, not explained by hearing loss, brain damage or lack of exposure to music. Despite inferior musical performance, amusics exhibit normal auditory cortical responses, with abnormal neural correlates suggested to lie beyond auditory cortices. Here we show, using auditory brainstem responses to complex sounds in humans, that fine-grained automatic processing of sounds is impoverished in amusia. Compared with matched non-musician controls, spectral amplitude was decreased in amusics for higher harmonic components of the auditory brainstem response. We also found a delayed response to the early transient aspects of the auditory stimulus in amusics. Neural measures of spectral amplitude and response timing correlated with participants' behavioral assessments of music processing. We demonstrate, for the first time, that amusia affects how complex acoustic signals are processed in the auditory brainstem. This neural signature of amusia mirrors what is observed in musicians, such that the aspects of the auditory brainstem responses that are enhanced in musicians are degraded in amusics. By showing that gradients of music abilities are reflected in the auditory brainstem, our findings have implications not only for current models of amusia but also for auditory functioning in general. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Organization of ascending auditory pathways in the pigeon (Columba livia) as determined by autoradiographic methods

International Nuclear Information System (INIS)

Correia, M.J.; Eden, A.R.; Westlund, K.N.; Coulter, J.D.

1982-01-01

A mixture of tritiated proline and fucose was injected into the labyrinthine endolymphatic space of 5 white king pigeons (Columba livia). Using standard autoradiographic techniques, the authors observed transsynaptic labeling in ascending auditory pathways to the level of the mesencephalon. Auditory system structures, ipsilateral to the injection site, which labeled heavily were the cochlear nerve, the magnocellular and angular nuclei, and the superior olive. Those ipsilateral structures which were slightly labeled were the lateral lemniscus and the dorsal part of the lateral mesencephalic nucleus. Contralateral structures which labeled were the superior olive, lateral lemniscus, and dorsal part of the lateral mesencephalic nucleus. The results of this study suggest that ascending auditory pathways (to the level of mesencephalon) in the pigeon are more similar to those described for mammals in general than previously thought. (Auth.)

Organization of ascending auditory pathways in the pigeon (Columba livia) as determined by autoradiographic methods

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Correia, M.J.; Eden, A.R.; Westlund, K.N.; Coulter, J.D. (Texas Univ., Galveston (USA). Medical Branch)

1982-02-25

A mixture of tritiated proline and fucose was injected into the labyrinthine endolymphatic space of 5 white king pigeons (Columba livia). Using standard autoradiographic techniques, the authors observed transsynaptic labeling in ascending auditory pathways to the level of the mesencephalon. Auditory system structures, ipsilateral to the injection site, which labeled heavily were the cochlear nerve, the magnocellular and angular nuclei, and the superior olive. Those ipsilateral structures which were slightly labeled were the lateral lemniscus and the dorsal part of the lateral mesencephalic nucleus. Contralateral structures which labeled were the superior olive, lateral lemniscus, and dorsal part of the lateral mesencephalic nucleus. The results of this study suggest that ascending auditory pathways (to the level of mesencephalon) in the pigeon are more similar to those described for mammals in general than previously thought.

Comprehensive evaluation of a child with an auditory brainstem implant.

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Eisenberg, Laurie S; Johnson, Karen C; Martinez, Amy S; DesJardin, Jean L; Stika, Carren J; Dzubak, Danielle; Mahalak, Mandy Lutz; Rector, Emily P

2008-02-01

We had an opportunity to evaluate an American child whose family traveled to Italy to receive an auditory brainstem implant (ABI). The goal of this evaluation was to obtain insight into possible benefits derived from the ABI and to begin developing assessment protocols for pediatric clinical trials. Case study. Tertiary referral center. Pediatric ABI Patient 1 was born with auditory nerve agenesis. Auditory brainstem implant surgery was performed in December, 2005, in Verona, Italy. The child was assessed at the House Ear Institute, Los Angeles, in July 2006 at the age of 3 years 11 months. Follow-up assessment has continued at the HEAR Center in Birmingham, Alabama. Auditory brainstem implant. Performance was assessed for the domains of audition, speech and language, intelligence and behavior, quality of life, and parental factors. Patient 1 demonstrated detection of sound, speech pattern perception with visual cues, and inconsistent auditory-only vowel discrimination. Language age with signs was approximately 2 years, and vocalizations were increasing. Of normal intelligence, he exhibited attention deficits with difficulty completing structured tasks. Twelve months later, this child was able to identify speech patterns consistently; closed-set word identification was emerging. These results were within the range of performance for a small sample of similarly aged pediatric cochlear implant users. Pediatric ABI assessment with a group of well-selected children is needed to examine risk versus benefit in this population and to analyze whether open-set speech recognition is achievable.

The auditory brainstem response in two lizard species

DEFF Research Database (Denmark)

Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong

2010-01-01

Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal...... animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform......). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than...

Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

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Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

2014-10-01

Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even completely prevent the KHFAC onset response without a change in nerve conductivity.

Evolutionary conservation and neuronal mechanisms of auditory perceptual restoration.

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Petkov, Christopher I; Sutter, Mitchell L

2011-01-01

Auditory perceptual 'restoration' occurs when the auditory system restores an occluded or masked sound of interest. Behavioral work on auditory restoration in humans began over 50 years ago using it to model a noisy environmental scene with competing sounds. It has become clear that not only humans experience auditory restoration: restoration has been broadly conserved in many species. Behavioral studies in humans and animals provide a necessary foundation to link the insights being obtained from human EEG and fMRI to those from animal neurophysiology. The aggregate of data resulting from multiple approaches across species has begun to clarify the neuronal bases of auditory restoration. Different types of neural responses supporting restoration have been found, supportive of multiple mechanisms working within a species. Yet a general principle has emerged that responses correlated with restoration mimic the response that would have been given to the uninterrupted sound of interest. Using the same technology to study different species will help us to better harness animal models of 'auditory scene analysis' to clarify the conserved neural mechanisms shaping the perceptual organization of sound and to advance strategies to improve hearing in natural environmental settings. © 2010 Elsevier B.V. All rights reserved.

Renal sympathetic nerve, blood flow, and epithelial transport responses to thermal stress.

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Wilson, Thad E

2017-05-01

Thermal stress is a profound sympathetic stress in humans; kidney responses involve altered renal sympathetic nerve activity (RSNA), renal blood flow, and renal epithelial transport. During mild cold stress, RSNA spectral power but not total activity is altered, renal blood flow is maintained or decreased, and epithelial transport is altered consistent with a sympathetic stress coupled with central volume loaded state. Hypothermia decreases RSNA, renal blood flow, and epithelial transport. During mild heat stress, RSNA is increased, renal blood flow is decreased, and epithelial transport is increased consistent with a sympathetic stress coupled with a central volume unloaded state. Hyperthermia extends these directional changes, until heat illness results. Because kidney responses are very difficult to study in humans in vivo, this review describes and qualitatively evaluates an in vivo human skin model of sympathetically regulated epithelial tissue compared to that of the nephron. This model utilizes skin responses to thermal stress, involving 1) increased skin sympathetic nerve activity (SSNA), decreased skin blood flow, and suppressed eccrine epithelial transport during cold stress; and 2) increased SSNA, skin blood flow, and eccrine epithelial transport during heat stress. This model appears to mimic aspects of the renal responses. Investigations of skin responses, which parallel certain renal responses, may aid understanding of epithelial-sympathetic nervous system interactions during cold and heat stress. Copyright © 2016 Elsevier B.V. All rights reserved.

Removal of vestibular schwannoma and facial nerve preservation using small suboccipital retrosigmoid craniotomy

Institute of Scientific and Technical Information of China (English)

CHEN Ling; CHEN Li-hua; LING Feng; LIU Yun-sheng; Madjid Samii; Amir Samii

2010-01-01

Background Vestibular schwannoma, the commonest form of intracranial schwannoma, arises from the Schwann cells investing the vestibular nerve. At present, the surgery for vestibular schwannoma remains one of the most complicated operations demanding for surgical skills in neurosurgery. And the trend of minimal invasion should also be the major influence on the management of patients with vestibular schwannomas. We summarized the microsurgical removal experience in a recent series of vestibular schwannomas and presented the operative technique and cranial nerve preservation in order to improve the rates of total tumor removal and facial nerve preservation.Methods A retrospective analysis was performed in 145 patients over a 7-year period who suffered from vestibular schwannomas that had been microsurgicaily removed by suboccipital retrosigmoid transmeatus approach with small craniotomy. CT thinner scans revealed the tumor size in the internal auditory meatus and the relationship of the posterior wall of the internal acoustic meatus to the bone labyrinths preoperatively. Brain stem evoked potential was monitored intraoperatively. The posterior wall of the internal acoustic meatus was designedly drilled off. Patient records and operative reports, including data from the electrophysiological monitoring, follow-up audiometric examinations, and neuroradiological findings were analyzed.Results Total tumor resection was achieved in 140 cases (96.6%) and subtotal resection in 5 cases. The anatomical integrity of the facial nerve was preserved in 91.0% (132/145) of the cases. Intracranial end-to-end anastomosis of the facial nerve was performed in 7 cases. Functional preservation of the facial nerve was achieved in 115 patients (Grade Ⅰ and Grade Ⅱ, 79.3%). No patient died in this series. Preservation of nerves and vessels were as important as tumor removal dudng the operation. CT thinner scan could show the relationship between the posterior wall of the internal

Auditory Brainstem Responses and EMFs Generated by Mobile Phones.

Science.gov (United States)

Khullar, Shilpa; Sood, Archana; Sood, Sanjay

2013-12-01

There has been a manifold increase in the number of mobile phone users throughout the world with the current number of users exceeding 2 billion. However this advancement in technology like many others is accompanied by a progressive increase in the frequency and intensity of electromagnetic waves without consideration of the health consequences. The aim of our study was to advance our understanding of the potential adverse effects of GSM mobile phones on auditory brainstem responses (ABRs). 60 subjects were selected for the study and divided into three groups of 20 each based on their usage of mobile phones. Their ABRs were recorded and analysed for latency of waves I-V as well as interpeak latencies I-III, I-V and III-V (in ms). Results revealed no significant difference in the ABR parameters between group A (control group) and group B (subjects using mobile phones for maximum 30 min/day for 5 years). However the latency of waves was significantly prolonged in group C (subjects using mobile phones for 10 years for a maximum of 30 min/day) as compared to the control group. Based on our findings we concluded that long term exposure to mobile phones may affect conduction in the peripheral portion of the auditory pathway. However more research needs to be done to study the long term effects of mobile phones particularly of newer technologies like smart phones and 3G.

A new test of attention in listening (TAIL) predicts auditory performance.

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Zhang, Yu-Xuan; Barry, Johanna G; Moore, David R; Amitay, Sygal

2012-01-01

Attention modulates auditory perception, but there are currently no simple tests that specifically quantify this modulation. To fill the gap, we developed a new, easy-to-use test of attention in listening (TAIL) based on reaction time. On each trial, two clearly audible tones were presented sequentially, either at the same or different ears. The frequency of the tones was also either the same or different (by at least two critical bands). When the task required same/different frequency judgments, presentation at the same ear significantly speeded responses and reduced errors. A same/different ear (location) judgment was likewise facilitated by keeping tone frequency constant. Perception was thus influenced by involuntary orienting of attention along the task-irrelevant dimension. When information in the two stimulus dimensions were congruent (same-frequency same-ear, or different-frequency different-ear), response was faster and more accurate than when they were incongruent (same-frequency different-ear, or different-frequency same-ear), suggesting the involvement of executive control to resolve conflicts. In total, the TAIL yielded five independent outcome measures: (1) baseline reaction time, indicating information processing efficiency, (2) involuntary orienting of attention to frequency and (3) location, and (4) conflict resolution for frequency and (5) location. Processing efficiency and conflict resolution accounted for up to 45% of individual variances in the low- and high-threshold variants of three psychoacoustic tasks assessing temporal and spectral processing. Involuntary orientation of attention to the irrelevant dimension did not correlate with perceptual performance on these tasks. Given that TAIL measures are unlikely to be limited by perceptual sensitivity, we suggest that the correlations reflect modulation of perceptual performance by attention. The TAIL thus has the power to identify and separate contributions of different components of attention

Cranial nerve involvement in nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Oezyar, E.; Atahan, I.L.; Akyol, F.H.; Guerkaynak, M.; Zorlu, A.F.

1994-01-01

Between 1975 and 1989, 23 nasopharyngeal carcinoma patients presenting with cranial nerve involvement (CNI) of one or more nerves at the time of diagnosis were treated and followed-up in our department. All patients were irradiated with curative intent, and total doses of 50 to 70 Gy (median 65 Gy) were delivered to the nasopharynx. Cranial nerves VI, III, V, IV, IX, and XII were the most commonly involved nerves. The total response rate of cranial nerves was 74% in a median follow-up time of 2 years, with the highest rate observed in the third and sixth cranial nerves. All complete responses except two were observed in the first month after radiotherapy. (author)

Ramsay Hunt syndrome with unilateral polyneuropathy involving cranial nerves V, VII, VIII, and XII in a diabetic patient.

Science.gov (United States)

Sun, Wei-Lian; Yan, Jian-Liang; Chen, Li-Li

2011-01-01

Ramsay Hunt syndrome is a rare complication of the varicella zoster virus, defined as a peripheral facial palsy that typically results from involvement of the facial and auditory nerves. Ramsay Hunt syndrome can be associated with cranial nerves V, VI, IX, and X but rarely with XII. We describe an atypical case of Ramsay Hunt syndrome with multiple cranial nerve involvement of nerves V, VII, VIII, and XII. Antiviral drugs, antibiotics, insulin, and traditional Chinese drugs were administered immediately after admission. After 3 months of combination therapy, the patient had recovered satisfactorily. Herpes zoster can cause severe infections in diabetic patients and should be treated as soon after detection as possible. Ramsay Hunt syndrome should be recognized as a polycranial neuritis characterized by damage to sensory and motor nerves. In addition to facial and vestibular nerve paralysis, Ramsay Hunt syndrome may also involve cranial nerves V and XII.

Evaluation of phrenic nerve and diaphragm function with peripheral nerve stimulation and M-mode ultrasonography in potential pediatric phrenic nerve or diaphragm pacing candidates.

Science.gov (United States)

Skalsky, Andrew J; Lesser, Daniel J; McDonald, Craig M

2015-02-01

Assessing phrenic nerve function in the setting of diaphragmatic paralysis in diaphragm pacing candidates can be challenging. Traditional imaging modalities and electrodiagnostic evaluations are technically difficult. Either modality alone is not a direct measure of the function of the phrenic nerve and diaphragm unit. In this article, the authors present their method for evaluating phrenic nerve function and the resulting diaphragm function. Stimulating the phrenic nerve with transcutaneous stimulation and directly observing the resulting movement of the hemidiaphragm with M-mode ultrasonography provides quantitative data for predicting the success of advancing technologies such as phrenic nerve pacing and diaphragm pacing. Copyright © 2015 Elsevier Inc. All rights reserved.

Cross-modal prediction changes the timing of conscious access during the motion-induced blindness.

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Chang, Acer Y C; Kanai, Ryota; Seth, Anil K

2015-01-01

Despite accumulating evidence that perceptual predictions influence perceptual content, the relations between these predictions and conscious contents remain unclear, especially for cross-modal predictions. We examined whether predictions of visual events by auditory cues can facilitate conscious access to the visual stimuli. We trained participants to learn associations between auditory cues and colour changes. We then asked whether congruency between auditory cues and target colours would speed access to consciousness. We did this by rendering a visual target subjectively invisible using motion-induced blindness and then gradually changing its colour while presenting congruent or incongruent auditory cues. Results showed that the visual target gained access to consciousness faster in congruent than in incongruent trials; control experiments excluded potentially confounding effects of attention and motor response. The expectation effect was gradually established over blocks suggesting a role for extensive training. Overall, our findings show that predictions learned through cross-modal training can facilitate conscious access to visual stimuli. Copyright © 2014 Elsevier Inc. All rights reserved.

Modelling the Emergence and Dynamics of Perceptual Organisation in Auditory Streaming

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Mill, Robert W.; Bőhm, Tamás M.; Bendixen, Alexandra; Winkler, István; Denham, Susan L.

2013-01-01

Many sound sources can only be recognised from the pattern of sounds they emit, and not from the individual sound events that make up their emission sequences. Auditory scene analysis addresses the difficult task of interpreting the sound world in terms of an unknown number of discrete sound sources (causes) with possibly overlapping signals, and therefore of associating each event with the appropriate source. There are potentially many different ways in which incoming events can be assigned to different causes, which means that the auditory system has to choose between them. This problem has been studied for many years using the auditory streaming paradigm, and recently it has become apparent that instead of making one fixed perceptual decision, given sufficient time, auditory perception switches back and forth between the alternatives—a phenomenon known as perceptual bi- or multi-stability. We propose a new model of auditory scene analysis at the core of which is a process that seeks to discover predictable patterns in the ongoing sound sequence. Representations of predictable fragments are created on the fly, and are maintained, strengthened or weakened on the basis of their predictive success, and conflict with other representations. Auditory perceptual organisation emerges spontaneously from the nature of the competition between these representations. We present detailed comparisons between the model simulations and data from an auditory streaming experiment, and show that the model accounts for many important findings, including: the emergence of, and switching between, alternative organisations; the influence of stimulus parameters on perceptual dominance, switching rate and perceptual phase durations; and the build-up of auditory streaming. The principal contribution of the model is to show that a two-stage process of pattern discovery and competition between incompatible patterns can account for both the contents (perceptual organisations) and the

[Threefold intraoperative electrophysiological monitoring of vestibular neurectomy].

Science.gov (United States)

Hausler, R; Kasper, A

1991-01-01

A threefold intraoperative monitoring of facial nerve, auditory nerve and vestibular nerve function was performed in 14 cases of retrosigmoidal neurectomy. The facial nerve was monitoring with a pressure transducer placed against the cheek (Opalarm system). The auditory nerve was monitored with acoustically (click) evoked early potentials and the vestibular nerve was monitored with electrically evoked vestibular potentials obtained by direct stimulation (biphasic current pulses of 0.75-mA p-p, 100 us, 20/s) of the exposed vestibular nerve in the cerebellopontine angle before, during and after neurectomy. A characteristic vertex negative peak having a latency of approximately 2 ms and approximately 0.5 uV amplitude was obtained between a forehead and an ipsilateral ear lobe electrode (2 x 1,000 averaged responses over 10 ms) before the neurectomy. This response disappeared after selective vestibular nerve section proximal to the stimulation site. A diminished response amplitude was measured after incomplete nerve section. Simultaneous acoustic masking had no influence on the vestibular potential. The 14 operated patients became all free of vertiginous spells and drop-attacks except one patient who developed a contralateral Menière's. Facial nerve function remained normal in all. Hearing preservation was obtained in 12 patients (86%). The threefold intraoperative monitoring has turned out to be an additional safety factor for facial and auditory nerve preservation and, thanks to the recording of vestibular potentials, it increased the efficiency of vestibular neurectomy.

Auditory cortical function during verbal episodic memory encoding in Alzheimer's disease.

Science.gov (United States)

Dhanjal, Novraj S; Warren, Jane E; Patel, Maneesh C; Wise, Richard J S

2013-02-01

Episodic memory encoding of a verbal message depends upon initial registration, which requires sustained auditory attention followed by deep semantic processing of the message. Motivated by previous data demonstrating modulation of auditory cortical activity during sustained attention to auditory stimuli, we investigated the response of the human auditory cortex during encoding of sentences to episodic memory. Subsequently, we investigated this response in patients with mild cognitive impairment (MCI) and probable Alzheimer's disease (pAD). Using functional magnetic resonance imaging, 31 healthy participants were studied. The response in 18 MCI and 18 pAD patients was then determined, and compared to 18 matched healthy controls. Subjects heard factual sentences, and subsequent retrieval performance indicated successful registration and episodic encoding. The healthy subjects demonstrated that suppression of auditory cortical responses was related to greater success in encoding heard sentences; and that this was also associated with greater activity in the semantic system. In contrast, there was reduced auditory cortical suppression in patients with MCI, and absence of suppression in pAD. Administration of a central cholinesterase inhibitor (ChI) partially restored the suppression in patients with pAD, and this was associated with an improvement in verbal memory. Verbal episodic memory impairment in AD is associated with altered auditory cortical function, reversible with a ChI. Although these results may indicate the direct influence of pathology in auditory cortex, they are also likely to indicate a partially reversible impairment of feedback from neocortical systems responsible for sustained attention and semantic processing. Copyright © 2012 American Neurological Association.

Auditory and Non-Auditory Contributions for Unaided Speech Recognition in Noise as a Function of Hearing Aid Use.

Science.gov (United States)

Gieseler, Anja; Tahden, Maike A S; Thiel, Christiane M; Wagener, Kirsten C; Meis, Markus; Colonius, Hans

2017-01-01

Differences in understanding speech in noise among hearing-impaired individuals cannot be explained entirely by hearing thresholds alone, suggesting the contribution of other factors beyond standard auditory ones as derived from the audiogram. This paper reports two analyses addressing individual differences in the explanation of unaided speech-in-noise performance among n = 438 elderly hearing-impaired listeners ( mean = 71.1 ± 5.8 years). The main analysis was designed to identify clinically relevant auditory and non-auditory measures for speech-in-noise prediction using auditory (audiogram, categorical loudness scaling) and cognitive tests (verbal-intelligence test, screening test of dementia), as well as questionnaires assessing various self-reported measures (health status, socio-economic status, and subjective hearing problems). Using stepwise linear regression analysis, 62% of the variance in unaided speech-in-noise performance was explained, with measures Pure-tone average (PTA), Age , and Verbal intelligence emerging as the three most important predictors. In the complementary analysis, those individuals with the same hearing loss profile were separated into hearing aid users (HAU) and non-users (NU), and were then compared regarding potential differences in the test measures and in explaining unaided speech-in-noise recognition. The groupwise comparisons revealed significant differences in auditory measures and self-reported subjective hearing problems, while no differences in the cognitive domain were found. Furthermore, groupwise regression analyses revealed that Verbal intelligence had a predictive value in both groups, whereas Age and PTA only emerged significant in the group of hearing aid NU.

Narrow duplicated internal auditory canal: radiological findings and review of the literature

International Nuclear Information System (INIS)

Demir, Oezguen Ilhan; Cakmakci, Handan; Men, Sueleyman; Erdag, Taner Kemal

2005-01-01

Narrow duplicated internal auditory canal (IAC) is a rare malformation of the temporal bone that is associated with ipsilateral congenital sensorineural hearing loss. This may be an isolated finding or a part of a syndrome. Radiological examination should demonstrate aplasia or hypoplasia of the neural components of the narrow IAC, to guide the surgical approach. We report a 7-year-old boy with Klippel-Feil syndrome with a narrow double IAC with no sensorineural hearing loss but with conductive hearing loss. In this patient, the IAC consisted of two separate narrow bony canals clearly seen on 3D temporal bone CT and one nerve that was delineated on MRI. The contralateral external auditory canal was stenotic and the ossicles were dysplastic. (orig.)

Mouse Panx1 Is Dispensable for Hearing Acquisition and Auditory Function

Directory of Open Access Journals (Sweden)

Veronica Zorzi

2017-11-01

Full Text Available Panx1 forms plasma membrane channels in brain and several other organs, including the inner ear. Biophysical properties, activation mechanisms and modulators of Panx1 channels have been characterized in detail, however the impact of Panx1 on auditory function is unclear due to conflicts in published results. To address this issue, hearing performance and cochlear function of the Panx1−/− mouse strain, the first with a reported global ablation of Panx1, were scrutinized. Male and female homozygous (Panx1−/−, hemizygous (Panx1+/− and their wild type (WT siblings (Panx1+/+ were used for this study. Successful ablation of Panx1 was confirmed by RT-PCR and Western immunoblotting in the cochlea and brain of Panx1−/− mice. Furthermore, a previously validated Panx1-selective antibody revealed strong immunoreactivity in WT but not in Panx1−/− cochleae. Hearing sensitivity, outer hair cell-based “cochlear amplifier” and cochlear nerve function, analyzed by auditory brainstem response (ABR and distortion product otoacoustic emission (DPOAE recordings, were normal in Panx1+/− and Panx1−/− mice. In addition, we determined that global deletion of Panx1 impacts neither on connexin expression, nor on gap-junction coupling in the developing organ of Corti. Finally, spontaneous intercellular Ca2+ signal (ICS activity in organotypic cochlear cultures, which is key to postnatal development of the organ of Corti and essential for hearing acquisition, was not affected by Panx1 ablation. Therefore, our results provide strong evidence that, in mice, Panx1 is dispensable for hearing acquisition and auditory function.

Brain responses and looking behaviour during audiovisual speech integration in infants predict auditory speech comprehension in the second year of life.

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Elena V Kushnerenko

2013-07-01

Full Text Available The use of visual cues during the processing of audiovisual speech is known to be less efficient in children and adults with language difficulties and difficulties are known to be more prevalent in children from low-income populations. In the present study, we followed an economically diverse group of thirty-seven infants longitudinally from 6-9 months to 14-16 months of age. We used eye-tracking to examine whether individual differences in visual attention during audiovisual processing of speech in 6 to 9 month old infants, particularly when processing congruent and incongruent auditory and visual speech cues, might be indicative of their later language development. Twenty-two of these 6-9 month old infants also participated in an event-related potential (ERP audiovisual task within the same experimental session. Language development was then followed-up at the age of 14-16 months, using two measures of language development, the Preschool Language Scale (PLS and the Oxford Communicative Development Inventory (CDI. The results show that those infants who were less efficient in auditory speech processing at the age of 6-9 months had lower receptive language scores at 14-16 months. A correlational analysis revealed that the pattern of face scanning and ERP responses to audio-visually incongruent stimuli at 6-9 months were both significantly associated with language development at 14-16 months. These findings add to the understanding of individual differences in neural signatures of audiovisual processing and associated looking behaviour in infants.

Gradual nerve elongation affects nerve cell bodies and neuro-muscular junctions.

Science.gov (United States)

Kazuo Ikeda, K I; Masaki Matsuda, M M; Daisuke Yamauchi, D Y; Katsuro Tomita, K T; Shigenori Tanaka, S T

2005-07-01

The purpose of this study is to clarify the reactions of the neuro-muscular junction and nerve cell body to gradual nerve elongation. The sciatic nerves of Japanese white rabbits were lengthened by 30 mm in increments of 0.8 mm/day, 2.0 mm/day and 4.0 mm/day. A scanning electron microscopic examination showed no degenerative change at the neuro-muscular junction, even eight weeks after elongation in the 4-mm group. Hence, neuro-muscular junction is not critical for predicting damage from gradual nerve elongation. There were no axon reaction cells in the 0.8-mm group, a small amount in the 2-mm group, and a large amount in the 4-mm group. The rate of growth associated protein-43 positive nerve cells was significant in the 4-mm group. Hence, the safe speed for nerve cells appeared to be 0.8-mm/day, critical speed to be 2.0-mm/day, and dangerous speed to be 4.0-mm/day in this elongation model.

Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation.