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Sample records for auditory response properties

  1. 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...

  2. Response properties of the refractory auditory nerve fiber.

    Science.gov (United States)

    Miller, C A; Abbas, P J; Robinson, B K

    2001-09-01

    The refractory characteristics of auditory nerve fibers limit their ability to accurately encode temporal information. Therefore, they are relevant to the design of cochlear prostheses. It is also possible that the refractory property could be exploited by prosthetic devices to improve information transfer, as refractoriness may enhance the nerve's stochastic properties. Furthermore, refractory data are needed for the development of accurate computational models of auditory nerve fibers. We applied a two-pulse forward-masking paradigm to a feline model of the human auditory nerve to assess refractory properties of single fibers. Each fiber was driven to refractoriness by a single (masker) current pulse delivered intracochlearly. Properties of firing efficiency, latency, jitter, spike amplitude, and relative spread (a measure of dynamic range and stochasticity) were examined by exciting fibers with a second (probe) pulse and systematically varying the masker-probe interval (MPI). Responses to monophasic cathodic current pulses were analyzed. We estimated the mean absolute refractory period to be about 330 micros and the mean recovery time constant to be about 410 micros. A significant proportion of fibers (13 of 34) responded to the probe pulse with MPIs as short as 500 micros. Spike amplitude decreased with decreasing MPI, a finding relevant to the development of computational nerve-fiber models, interpretation of gross evoked potentials, and models of more central neural processing. A small mean decrement in spike jitter was noted at small MPI values. Some trends (such as spike latency-vs-MPI) varied across fibers, suggesting that sites of excitation varied across fibers. Relative spread was found to increase with decreasing MPI values, providing direct evidence that stochastic properties of fibers are altered under conditions of refractoriness.

  3. 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.

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

    Science.gov (United States)

    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.

  5. 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.

  6. 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.

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

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    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.

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

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    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).

  9. Transformation of binaural response properties in the ascending auditory pathway: influence of time-varying interaural phase disparity.

    Science.gov (United States)

    Spitzer, M W; Semple, M N

    1998-12-01

    Transformation of binaural response properties in the ascending auditory pathway: influence of time-varying interaural phase disparity. J. Neurophysiol. 80: 3062-3076, 1998. Previous studies demonstrated that tuning of inferior colliculus (IC) neurons to interaural phase disparity (IPD) is often profoundly influenced by temporal variation of IPD, which simulates the binaural cue produced by a moving sound source. To determine whether sensitivity to simulated motion arises in IC or at an earlier stage of binaural processing we compared responses in IC with those of two major IPD-sensitive neuronal classes in the superior olivary complex (SOC), neurons whose discharges were phase locked (PL) to tonal stimuli and those that were nonphase locked (NPL). Time-varying IPD stimuli consisted of binaural beats, generated by presenting tones of slightly different frequencies to the two ears, and interaural phase modulation (IPM), generated by presenting a pure tone to one ear and a phase modulated tone to the other. IC neurons and NPL-SOC neurons were more sharply tuned to time-varying than to static IPD, whereas PL-SOC neurons were essentially uninfluenced by the mode of stimulus presentation. Preferred IPD was generally similar in responses to static and time-varying IPD for all unit populations. A few IC neurons were highly influenced by the direction and rate of simulated motion, but the major effect for most IC neurons and all SOC neurons was a linear shift of preferred IPD at high rates-attributable to response latency. Most IC and NPL-SOC neurons were strongly influenced by IPM stimuli simulating motion through restricted ranges of azimuth; simulated motion through partially overlapping azimuthal ranges elicited discharge profiles that were highly discontiguous, indicating that the response associated with a particular IPD is dependent on preceding portions of the stimulus. In contrast, PL-SOC responses tracked instantaneous IPD throughout the trajectory of simulated

  10. Response properties of neighboring neurons in the auditory midbrain for pure-tone stimulation: a tetrode study.

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    Seshagiri, Chandran V; Delgutte, Bertrand

    2007-10-01

    The complex anatomical structure of the central nucleus of the inferior colliculus (ICC), the principal auditory nucleus in the midbrain, may provide the basis for functional organization of auditory information. To investigate this organization, we used tetrodes to record from neighboring neurons in the ICC of anesthetized cats and studied the similarity and difference among the responses of these neurons to pure-tone stimuli using widely used physiological characterizations. Consistent with the tonotopic arrangement of neurons in the ICC and reports of a threshold map, we found a high degree of correlation in the best frequencies (BFs) of neighboring neurons, which were mostly binaural beats. However, the characteristic phases (CPs) of neighboring neurons revealed a significant correlation. Because the CP is related to the neural mechanisms generating the ITD sensitivity, this result is consistent with segregation of inputs to the ICC from the lateral and medial superior olives.

  11. 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.

  12. 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.

  13. 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.

  14. Visual-induced expectations modulate auditory cortical responses

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    Virginie evan Wassenhove

    2015-02-01

    Full Text Available Active sensing has important consequences on multisensory processing (Schroeder et al. 2010. Here, we asked whether in the absence of saccades, the position of the eyes and the timing of transient colour changes of visual stimuli could selectively affect the excitability of auditory cortex by predicting the where and the when of a sound, respectively. Human participants were recorded with magnetoencephalography (MEG while maintaining the position of their eyes on the left, right, or centre of the screen. Participants counted colour changes of the fixation cross while neglecting sounds which could be presented to the left, right or both ears. First, clear alpha power increases were observed in auditory cortices, consistent with participants’ attention directed to visual inputs. Second, colour changes elicited robust modulations of auditory cortex responses (when prediction seen as ramping activity, early alpha phase-locked responses, and enhanced high-gamma band responses in the contralateral side of sound presentation. Third, no modulations of auditory evoked or oscillatory activity were found to be specific to eye position. Altogether, our results suggest that visual transience can automatically elicit a prediction of when a sound will occur by changing the excitability of auditory cortices irrespective of the attended modality, eye position or spatial congruency of auditory and visual events. To the contrary, auditory cortical responses were not significantly affected by eye position suggesting that where predictions may require active sensing or saccadic reset to modulate auditory cortex responses, notably in the absence of spatial orientation to sounds.

  15. 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.

  16. 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.

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

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    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…

  18. Auditory Evoked Responses in Neonates by MEG

    International Nuclear Information System (INIS)

    Hernandez-Pavon, J. C.; Sosa, M.; Lutter, W. J.; Maier, M.; Wakai, R. T.

    2008-01-01

    Magnetoencephalography is a biomagnetic technique with outstanding potential for neurodevelopmental studies. In this work, we have used MEG to determinate if newborns can discriminate between different stimuli during the first few months of life. Five neonates were stimulated during several minutes with auditory stimulation. The results suggest that the newborns are able to discriminate between different stimuli despite their early age

  19. Hearing in action; auditory properties of neurones in the red nucleus of alert primates

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    Jonathan Murray Lovell

    2014-05-01

    Full Text Available The response of neurones in the Red Nucleus pars magnocellularis (RNm to both tone bursts and electrical stimulation were observed in three cynomolgus monkeys (Macaca fascicularis, in a series of studies primarily designed to characterise the influence of the dopaminergic ventral midbrain on auditory processing. Compared to its role in motor behaviour, little is known about the sensory response properties of neurons in the red nucleus; particularly those concerning the auditory modality. Sites in the RN were recognised by observing electrically evoked body movements characteristic for this deep brain structure. In this study we applied brief monopolar electrical stimulation to 118 deep brain sites at a maximum intensity of 200 µA, thus evoking minimal body movements. Auditory sensitivity of RN neurons was analysed more thoroughly at 15 sites, with the majority exhibiting broad tuning curves and phase locking up to 1.03 kHz. Since the RN appears to receive inputs from a very early stage of the ascending auditory system, our results suggest that sounds can modify the motor control exerted by this brain nucleus. At selected locations, we also tested for the presence of functional connections between the RN and the auditory cortex by inserting additional microelectrodes into the auditory cortex and investigating how action potentials and local field potentials were affected by electrical stimulation of the RN.

  20. 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

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. Changes in Properties of Auditory Nerve Synapses following Conductive Hearing Loss.

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    Zhuang, Xiaowen; Sun, Wei; Xu-Friedman, Matthew A

    2017-01-11

    Auditory activity plays an important role in the development of the auditory system. Decreased activity can result from conductive hearing loss (CHL) associated with otitis media, which may lead to long-term perceptual deficits. The effects of CHL have been mainly studied at later stages of the auditory pathway, but early stages remain less examined. However, changes in early stages could be important because they would affect how information about sounds is conveyed to higher-order areas for further processing and localization. We examined the effects of CHL at auditory nerve synapses onto bushy cells in the mouse anteroventral cochlear nucleus following occlusion of the ear canal. These synapses, called endbulbs of Held, normally show strong depression in voltage-clamp recordings in brain slices. After 1 week of CHL, endbulbs showed even greater depression, reflecting higher release probability. We observed no differences in quantal size between control and occluded mice. We confirmed these observations using mean-variance analysis and the integration method, which also revealed that the number of release sites decreased after occlusion. Consistent with this, synaptic puncta immunopositive for VGLUT1 decreased in area after occlusion. The level of depression and number of release sites both showed recovery after returning to normal conditions. Finally, bushy cells fired fewer action potentials in response to evoked synaptic activity after occlusion, likely because of increased depression and decreased input resistance. These effects appear to reflect a homeostatic, adaptive response of auditory nerve synapses to reduced activity. These effects may have important implications for perceptual changes following CHL. Normal hearing is important to everyday life, but abnormal auditory experience during development can lead to processing disorders. For example, otitis media reduces sound to the ear, which can cause long-lasting deficits in language skills and verbal

  6. 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...

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

    Science.gov (United States)

    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.

  8. Response actions influence the categorization of directions in auditory space

    Directory of Open Access Journals (Sweden)

    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.

  9. 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

  10. Brain stem auditory evoked responses in chronic alcoholics.

    OpenAIRE

    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...

  11. 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

  12. Amelioration of Auditory Response by DA9801 in Diabetic Mouse

    Directory of Open Access Journals (Sweden)

    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.

  13. 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.

  14. 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.

  15. Neural responses to complex auditory rhythms: the role of attending

    Directory of Open Access Journals (Sweden)

    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.

  16. A comparison of auditory brainstem responses across diving bird species

    Science.gov (United States)

    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.

  17. Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

    Directory of Open Access Journals (Sweden)

    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.

  18. Differential Receptive Field Properties of Parvalbumin and Somatostatin Inhibitory Neurons in Mouse Auditory Cortex.

    Science.gov (United States)

    Li, Ling-Yun; Xiong, Xiaorui R; Ibrahim, Leena A; Yuan, Wei; Tao, Huizhong W; Zhang, Li I

    2015-07-01

    Cortical inhibitory circuits play important roles in shaping sensory processing. In auditory cortex, however, functional properties of genetically identified inhibitory neurons are poorly characterized. By two-photon imaging-guided recordings, we specifically targeted 2 major types of cortical inhibitory neuron, parvalbumin (PV) and somatostatin (SOM) expressing neurons, in superficial layers of mouse auditory cortex. We found that PV cells exhibited broader tonal receptive fields with lower intensity thresholds and stronger tone-evoked spike responses compared with SOM neurons. The latter exhibited similar frequency selectivity as excitatory neurons. The broader/weaker frequency tuning of PV neurons was attributed to a broader range of synaptic inputs and stronger subthreshold responses elicited, which resulted in a higher efficiency in the conversion of input to output. In addition, onsets of both the input and spike responses of SOM neurons were significantly delayed compared with PV and excitatory cells. Our results suggest that PV and SOM neurons engage in auditory cortical circuits in different manners: while PV neurons may provide broadly tuned feedforward inhibition for a rapid control of ascending inputs to excitatory neurons, the delayed and more selective inhibition from SOM neurons may provide a specific modulation of feedback inputs on their distal dendrites. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

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

    Science.gov (United States)

    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.

  20. Phencyclidine Disrupts the Auditory Steady State Response in Rats.

    Directory of Open Access Journals (Sweden)

    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.

  1. Modeling auditory-nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

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

    2014-01-01

    μs, which is large enough to affect the temporal coding of sounds and hence, potentially, the communication abilities of the CI listener. In the present study, two recently proposed models of electric stimulation of the AN [1,2] were considered in terms of their efficacy to predict the spike timing...... for anodic and cathodic stimulation of the AN of cat [3]. The models’ responses to the electrical pulses of various shapes [4,5,6] were also analyzed. It was found that, while the models can account for the firing rates in response to various biphasic pulse shapes, they fail to correctly describe the timing......Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electrical transduction in the inner ear. Trains of biphasic, charge balanced pulses (anodic and cathodic) are used as stimuli to avoid damage of the tissue. The pulses of either polarity are capable...

  2. 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.

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

    Science.gov (United States)

    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

  4. 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...

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

    Science.gov (United States)

    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.

  6. Low-frequency versus high-frequency synchronisation in chirp-evoked auditory brainstem responses

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Gøtsche-Rasmussen, Kristian

    2011-01-01

    This study investigates the frequency specific contribution to the auditory brainstem response (ABR) of chirp stimuli. Frequency rising chirps were designed to compensate for the cochlear traveling wave delay, and lead to larger wave-V amplitudes than for click stimuli as more auditory nerve fibr...

  7. 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.

  8. The auditory brainstem response in two lizard species.

    Science.gov (United States)

    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong; Carr, Catherine; Dooling, Robert J

    2010-08-01

    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 in response to click stimulation showed one prominent and several smaller peaks occurring within 10 ms of the stimulus onset. ABRs to brief tone bursts revealed that geckos and anoles were most sensitive between 1.6-2 kHz and had similar hearing sensitivity up to about 5 kHz (thresholds typically 20-50 dB SPL). 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 in most bird species.

  9. Developmental profiles of the intrinsic properties and synaptic function of auditory neurons in preterm and term baboon neonates.

    Science.gov (United States)

    Kim, Sei Eun; Lee, Seul Yi; Blanco, Cynthia L; Kim, Jun Hee

    2014-08-20

    The human fetus starts to hear and undergoes major developmental changes in the auditory system during the third trimester of pregnancy. Although there are significant data regarding development of the auditory system in rodents, changes in intrinsic properties and synaptic function of auditory neurons in developing primate brain at hearing onset are poorly understood. We performed whole-cell patch-clamp recordings of principal neurons in the medial nucleus of trapezoid body (MNTB) in preterm and term baboon brainstem slices to study the structural and functional maturation of auditory synapses. Each MNTB principal neuron received an excitatory input from a single calyx of Held terminal, and this one-to-one pattern of innervation was already formed in preterm baboons delivered at 67% of normal gestation. There was no difference in frequency or amplitude of spontaneous excitatory postsynaptic synaptic currents between preterm and term MNTB neurons. In contrast, the frequency of spontaneous GABA(A)/glycine receptor-mediated inhibitory postsynaptic synaptic currents, which were prevalent in preterm MNTB neurons, was significantly reduced in term MNTB neurons. Preterm MNTB neurons had a higher input resistance than term neurons and fired in bursts, whereas term MNTB neurons fired a single action potential in response to suprathreshold current injection. The maturation of intrinsic properties and dominance of excitatory inputs in the primate MNTB allow it to take on its mature role as a fast and reliable relay synapse. Copyright © 2014 the authors 0270-6474/14/3411399-06$15.00/0.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  12. Trait aspects of auditory mismatch negativity predict response to auditory training in individuals with early illness schizophrenia.

    Science.gov (United States)

    Biagianti, Bruno; Roach, Brian J; Fisher, Melissa; Loewy, Rachel; Ford, Judith M; Vinogradov, Sophia; Mathalon, Daniel H

    2017-01-01

    Individuals with schizophrenia have heterogeneous impairments of the auditory processing system that likely mediate differences in the cognitive gains induced by auditory training (AT). Mismatch negativity (MMN) is an event-related potential component reflecting auditory echoic memory, and its amplitude reduction in schizophrenia has been linked to cognitive deficits. Therefore, MMN may predict response to AT and identify individuals with schizophrenia who have the most to gain from AT. Furthermore, to the extent that AT strengthens auditory deviance processing, MMN may also serve as a readout of the underlying changes in the auditory system induced by AT. Fifty-six individuals early in the course of a schizophrenia-spectrum illness (ESZ) were randomly assigned to 40 h of AT or Computer Games (CG). Cognitive assessments and EEG recordings during a multi-deviant MMN paradigm were obtained before and after AT and CG. Changes in these measures were compared between the treatment groups. Baseline and trait-like MMN data were evaluated as predictors of treatment response. MMN data collected with the same paradigm from a sample of Healthy Controls (HC; n = 105) were compared to baseline MMN data from the ESZ group. Compared to HC, ESZ individuals showed significant MMN reductions at baseline ( p = .003). Reduced Double-Deviant MMN was associated with greater general cognitive impairment in ESZ individuals ( p = .020). Neither ESZ intervention group showed significant change in MMN. We found high correlations in all MMN deviant types (rs = .59-.68, all ps < .001) between baseline and post-intervention amplitudes irrespective of treatment group, suggesting trait-like stability of the MMN signal. Greater deficits in trait-like Double-Deviant MMN predicted greater cognitive improvements in the AT group ( p = .02), but not in the CG group. In this sample of ESZ individuals, AT had no effect on auditory deviance processing as assessed by MMN. In ESZ individuals, baseline MMN

  13. Diverse Intrinsic Properties Shape Functional Phenotype of Low-Frequency Neurons in the Auditory Brainstem

    Directory of Open Access Journals (Sweden)

    Hui Hong

    2018-06-01

    Full Text Available In the auditory system, tonotopy is the spatial arrangement of where sounds of different frequencies are processed. Defined by the organization of neurons and their inputs, tonotopy emphasizes distinctions in neuronal structure and function across topographic gradients and is a common feature shared among vertebrates. In this study we characterized action potential firing patterns and ion channel properties from neurons located in the extremely low-frequency region of the chicken nucleus magnocellularis (NM, an auditory brainstem structure. We found that NM neurons responsible for encoding the lowest sound frequencies (termed NMc neurons have enhanced excitability and fired bursts of action potentials to sinusoidal inputs ≤10 Hz; a distinct firing pattern compared to higher-frequency neurons. This response property was due to lower amounts of voltage dependent potassium (KV conductances, unique combination of KV subunits and specialized sodium (NaV channel properties. Particularly, NMc neurons had significantly lower KV1 and KV3 currents, but higher KV2 current. NMc neurons also showed larger and faster transient NaV current (INaT with different voltage dependence of inactivation from higher-frequency neurons. In contrast, significantly smaller resurgent sodium current (INaR was present in NMc with kinetics and voltage dependence that differed from higher-frequency neurons. Immunohistochemistry showed expression of NaV1.6 channel subtypes across the tonotopic axis. However, various immunoreactive patterns were observed between regions, likely underlying some tonotopic differences in INaT and INaR. Finally, using pharmacology and computational modeling, we concluded that KV3, KV2 channels and INaR work synergistically to regulate burst firing in NMc.

  14. 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.

  15. Human auditory steady state responses to binaural and monaural beats.

    Science.gov (United States)

    Schwarz, D W F; Taylor, P

    2005-03-01

    Binaural beat sensations depend upon a central combination of two different temporally encoded tones, separately presented to the two ears. We tested the feasibility to record an auditory steady state evoked response (ASSR) at the binaural beat frequency in order to find a measure for temporal coding of sound in the human EEG. We stimulated each ear with a distinct tone, both differing in frequency by 40Hz, to record a binaural beat ASSR. As control, we evoked a beat ASSR in response to both tones in the same ear. We band-pass filtered the EEG at 40Hz, averaged with respect to stimulus onset and compared ASSR amplitudes and phases, extracted from a sinusoidal non-linear regression fit to a 40Hz period average. A 40Hz binaural beat ASSR was evoked at a low mean stimulus frequency (400Hz) but became undetectable beyond 3kHz. Its amplitude was smaller than that of the acoustic beat ASSR, which was evoked at low and high frequencies. Both ASSR types had maxima at fronto-central leads and displayed a fronto-occipital phase delay of several ms. The dependence of the 40Hz binaural beat ASSR on stimuli at low, temporally coded tone frequencies suggests that it may objectively assess temporal sound coding ability. The phase shift across the electrode array is evidence for more than one origin of the 40Hz oscillations. The binaural beat ASSR is an evoked response, with novel diagnostic potential, to a signal that is not present in the stimulus, but generated within the brain.

  16. 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.

  17. The electrical properties of auditory hair cells in the frog amphibian papilla.

    Science.gov (United States)

    Smotherman, M S; Narins, P M

    1999-07-01

    The amphibian papilla (AP) is the principal auditory organ of the frog. Anatomical and neurophysiological evidence suggests that this hearing organ utilizes both mechanical and electrical (hair cell-based) frequency tuning mechanisms, yet relatively little is known about the electrophysiology of AP hair cells. Using the whole-cell patch-clamp technique, we have investigated the electrical properties and ionic currents of isolated hair cells along the rostrocaudal axis of the AP. Electrical resonances were observed in the voltage response of hair cells harvested from the rostral and medial, but not caudal, regions of the AP. Two ionic currents, ICa and IK(Ca), were observed in every hair cell; however, their amplitudes varied substantially along the epithelium. Only rostral hair cells exhibited an inactivating potassium current (IA), whereas an inwardly rectifying potassium current (IK1) was identified only in caudal AP hair cells. Electrically tuned hair cells exhibited resonant frequencies from 50 to 375 Hz, which correlated well with hair cell position and the tonotopic organization of the papilla. Variations in the kinetics of the outward current contribute substantially to the determination of resonant frequency. ICa and IK(Ca) amplitudes increased with resonant frequency, reducing the membrane time constant with increasing resonant frequency. We conclude that a tonotopically organized hair cell substrate exists to support electrical tuning in the rostromedial region of the frog amphibian papilla and that the cellular mechanisms for frequency determination are very similar to those reported for another electrically tuned auditory organ, the turtle basilar papilla.

  18. 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.

  19. 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...

  20. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. Effects of contralateral noise on the 20-Hz auditory steady state response--magnetoencephalography study.

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    Hajime Usubuchi

    Full Text Available The auditory steady state response (ASSR is an oscillatory brain response, which is phase locked to the rhythm of an auditory stimulus. ASSRs have been recorded in response to a wide frequency range of modulation and/or repetition, but the physiological features of the ASSRs are somewhat different depending on the modulation frequency. Recently, the 20-Hz ASSR has been emphasized in clinical examinations, especially in the area of psychiatry. However, little is known about the physiological properties of the 20-Hz ASSR, compared to those of the 40-Hz and 80-Hz ASSRs. The effects of contralateral noise on the ASSR are known to depend on the modulation frequency to evoke ASSR. However, the effects of contralateral noise on the 20-Hz ASSR are not known. Here we assessed the effects of contralateral white noise at a level of 70 dB SPL on the 20-Hz and 40-Hz ASSRs using a helmet-shaped magnetoencephalography system in 9 healthy volunteers (8 males and 1 female, mean age 31.2 years. The ASSRs were elicited by monaural 1000-Hz 5-s tone bursts amplitude-modulated at 20 and 39 Hz and presented at 80 dB SPL. Contralateral noise caused significant suppression of both the 20-Hz and 40-Hz ASSRs, although suppression was significantly smaller for the 20-Hz ASSRs than the 40-Hz ASSRs. Moreover, the greatest suppression of both 20-Hz and 40-Hz ASSRs occurred in the right hemisphere when stimuli were presented to the right ear with contralateral noise. The present study newly showed that 20-Hz ASSRs are suppressed by contralateral noise, which may be important both for characterization of the 20-Hz ASSR and for interpretation in clinical situations. Physicians must be aware that the 20-Hz ASSR is significantly suppressed by sound (e.g. masking noise or binaural stimulation applied to the contralateral ear.

  4. A model of auditory nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

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

    Cochlear implants (CI) stimulate the auditory nerve (AN) with a train of symmetric biphasic current pulses comprising of a cathodic and an anodic phase. The cathodic phase is intended to depolarize the membrane of the neuron and to initiate an action potential (AP) and the anodic phase to neutral......Cochlear implants (CI) stimulate the auditory nerve (AN) with a train of symmetric biphasic current pulses comprising of a cathodic and an anodic phase. The cathodic phase is intended to depolarize the membrane of the neuron and to initiate an action potential (AP) and the anodic phase......-and-fire neuron with two partitions responding individually to anodic and cathodic stimulation. Membrane noise was parameterized based on reported relative spread of AN neurons. Firing efficiency curves and spike-latency distributions were simulated for monophasic and symmetric biphasic stimulation...

  5. 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.

  6. Comparison of perceptual properties of auditory streaming between spectral and amplitude modulation domains.

    Science.gov (United States)

    Yamagishi, Shimpei; Otsuka, Sho; Furukawa, Shigeto; Kashino, Makio

    2017-07-01

    The two-tone sequence (ABA_), which comprises two different sounds (A and B) and a silent gap, has been used to investigate how the auditory system organizes sequential sounds depending on various stimulus conditions or brain states. Auditory streaming can be evoked by differences not only in the tone frequency ("spectral cue": ΔF TONE , TONE condition) but also in the amplitude modulation rate ("AM cue": ΔF AM , AM condition). The aim of the present study was to explore the relationship between the perceptual properties of auditory streaming for the TONE and AM conditions. A sequence with a long duration (400 repetitions of ABA_) was used to examine the property of the bistability of streaming. The ratio of feature differences that evoked an equivalent probability of the segregated percept was close to the ratio of the Q-values of the auditory and modulation filters, consistent with a "channeling theory" of auditory streaming. On the other hand, for values of ΔF AM and ΔF TONE evoking equal probabilities of the segregated percept, the number of perceptual switches was larger for the TONE condition than for the AM condition, indicating that the mechanism(s) that determine the bistability of auditory streaming are different between or sensitive to the two domains. Nevertheless, the number of switches for individual listeners was positively correlated between the spectral and AM domains. The results suggest a possibility that the neural substrates for spectral and AM processes share a common switching mechanism but differ in location and/or in the properties of neural activity or the strength of internal noise at each level. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  7. 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.

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

    Science.gov (United States)

    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.

  9. (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.

  10. 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.

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

    Science.gov (United States)

    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.

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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.  

  14. 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.

    Directory of Open Access Journals (Sweden)

    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.

  15. Ventilatory response to induced auditory arousals during NREM sleep.

    Science.gov (United States)

    Badr, M S; Morgan, B J; Finn, L; Toiber, F S; Crabtree, D C; Puleo, D S; Skatrud, J B

    1997-09-01

    Sleep state instability is a potential mechanism of central apnea/hypopnea during non-rapid eye movement (NREM) sleep. To investigate this postulate, we induced brief arousals by delivering transient (0.5 second) auditory stimuli during stable NREM sleep in eight normal subjects. Arousal was determined according to American Sleep Disorders Association (ASDA) criteria. A total of 96 trials were conducted; 59 resulted in cortical arousal and 37 did not result in arousal. In trials associated with arousal, minute ventilation (VE) increased from 5.1 +/- 1.24 minutes to 7.5 +/- 2.24 minutes on the first posttone breath (p = 0.001). However, no subsequent hypopnea or apnea occurred as VE decreased gradually to 4.8 +/- 1.5 l/minute (p > 0.05) on the fifth posttone breath. Trials without arousal did not result in hyperpnea on the first breath nor subsequent hypopnea. We conclude that 1) auditory stimulation resulted in transient hyperpnea only if associated with cortical arousal; 2) hypopnea or apnea did not occur following arousal-induced hyperpnea in normal subjects; 3) interaction with fluctuating chemical stimuli or upper airway resistance may be required for arousals to cause sleep-disordered breathing.

  16. 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

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

    Science.gov (United States)

    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

  18. 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....

  19. Auditory cues increase the hippocampal response to unimodal virtual reality.

    Science.gov (United States)

    Andreano, Joseph; Liang, Kevin; Kong, Lingjun; Hubbard, David; Wiederhold, Brenda K; Wiederhold, Mark D

    2009-06-01

    Previous research suggests that the effectiveness of virtual reality exposure therapy should increase as the experience becomes more immersive. However, the neural mechanisms underlying the experience of immersion are not yet well understood. To address this question, neural activity during exposure to two virtual worlds was measured by functional magnetic resonance imaging (fMRI). Two levels of immersion were used: unimodal (video only) and multimodal (video plus audio). The results indicated increased activity in both auditory and visual sensory cortices during multimodal presentation. Additionally, multimodal presentation elicited increased activity in the hippocampus, a region well known to be involved in learning and memory. The implications of this finding for exposure therapy are discussed.

  20. 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

  1. Tone and call responses of units in the auditory nerve and dorsal medullary nucleus of Xenopus laevis

    DEFF Research Database (Denmark)

    Elliott, Taffeta M.; Christensen-Dalsgaard, Jakob; Kelley, Darcy B.

    2007-01-01

    The clawed frog Xenopus laevis produces vocalizations consisting of distinct patterns of clicks. This study provides the first description of spontaneous, pure-tone and communication-signal evoked discharge properties of auditory nerve (n.VIII) fibers and dorsal medullary nucleus (DMN) cells...... in an obligatorily aquatic anuran. Responses of 297 n.VIII and 253 DMN units are analyzed for spontaneous rates (SR), frequency tuning, rate-intensity functions, and firing rate adaptation, with a view to how these basic characteristics shape responses to recorded call stimuli. Response properties generally resemble......Hz with approximately 500 Hz in 3 dB bandwidth. SRs range from 0 to 80 (n.VIII) and 0 to 73 spikes/s (DMN). Nerve and DMN units of all CFs follow click rates in natural calls,

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

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    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.

  3. 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...

  4. Auditory Brainstem Response to Complex Sounds Predicts Self-Reported Speech-in-Noise Performance

    Science.gov (United States)

    Anderson, Samira; Parbery-Clark, Alexandra; White-Schwoch, Travis; Kraus, Nina

    2013-01-01

    Purpose: To compare the ability of the auditory brainstem response to complex sounds (cABR) to predict subjective ratings of speech understanding in noise on the Speech, Spatial, and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004) relative to the predictive ability of the Quick Speech-in-Noise test (QuickSIN; Killion, Niquette,…

  5. Auditory Middle Latency Responses in Chronic Smokers Compared to Nonsmokers: Differential Effects of Stimulus and Age

    Science.gov (United States)

    Ramkissoon, Ishara; Beverly, Brenda L.

    2014-01-01

    Purpose: Effects of clicks and tonebursts on early and late auditory middle latency response (AMLR) components were evaluated in young and older cigarette smokers and nonsmokers. Method: Participants ( n = 49) were categorized by smoking and age into 4 groups: (a) older smokers, (b) older nonsmokers, (c) young smokers, and (d) young nonsmokers.…

  6. 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.

  7. 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...

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Percepts, not acoustic properties, are the units of auditory short-term memory.

    Science.gov (United States)

    Mathias, Samuel R; von Kriegstein, Katharina

    2014-04-01

    For decades, researchers have sought to understand the organizing principles of auditory and visual short-term memory (STM). Previous work in audition has suggested that there are independent memory stores for different sound features, but the nature of the representations retained within these stores is currently unclear. Do they retain perceptual features, or do they instead retain representations of the sound's specific acoustic properties? In the present study we addressed this question by measuring listeners' abilities to keep one of three acoustic properties (interaural time difference [ITD], interaural level difference [ILD], or frequency) in memory when the target sound was followed by interfering sounds that varied randomly in one of the same properties. Critically, ITD and ILD evoked the same percept (spatial location), despite being acoustically different and having different physiological correlates, whereas frequency evoked a different percept (pitch). The results showed that listeners found it difficult to remember the percept of spatial location when the interfering tones varied either in ITD or ILD, but not when they varied in frequency. The study demonstrates that percepts are the units of auditory STM, and provides testable predictions for future neuroscientific work on both auditory and visual STM.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  18. Information-Theoretic Properties of Auditory Sequences Dynamically Influence Expectation and Memory.

    Science.gov (United States)

    Agres, Kat; Abdallah, Samer; Pearce, Marcus

    2018-01-01

    A basic function of cognition is to detect regularities in sensory input to facilitate the prediction and recognition of future events. It has been proposed that these implicit expectations arise from an internal predictive coding model, based on knowledge acquired through processes such as statistical learning, but it is unclear how different types of statistical information affect listeners' memory for auditory stimuli. We used a combination of behavioral and computational methods to investigate memory for non-linguistic auditory sequences. Participants repeatedly heard tone sequences varying systematically in their information-theoretic properties. Expectedness ratings of tones were collected during three listening sessions, and a recognition memory test was given after each session. Information-theoretic measures of sequential predictability significantly influenced listeners' expectedness ratings, and variations in these properties had a significant impact on memory performance. Predictable sequences yielded increasingly better memory performance with increasing exposure. Computational simulations using a probabilistic model of auditory expectation suggest that listeners dynamically formed a new, and increasingly accurate, implicit cognitive model of the information-theoretic structure of the sequences throughout the experimental session. Copyright © 2017 Cognitive Science Society, Inc.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Auditory stimuli elicit hippocampal neuronal responses during sleep

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    Ekaterina eVinnik

    2012-06-01

    Full Text Available To investigate how hippocampal neurons code behaviorally salient stimuli, we recorded from neurons in the CA1 region of hippocampus in rats while they learned to associate the presence of sound with water reward. Rats learned to alternate between two reward ports at which, in 50 percent of the trials, sound stimuli were presented followed by water reward after a 3-second delay. Sound at the water port predicted subsequent reward delivery in 100 percent of the trials and the absence of sound predicted reward omission. During this task, 40% of recorded neurons fired differently according to which of the 2 reward ports the rat was visiting. A smaller fraction of neurons demonstrated onset response to sound/nosepoke (19% and reward delivery (24%. When the sounds were played during passive wakefulness, 8% of neurons responded with short latency onset responses; 25% of neurons responded to sounds when they were played during sleep. Based on the current findings and the results of previous experiments we propose the existence of two types of hippocampal neuronal responses to sounds: sound-onset responses with very short latency and longer-lasting sound-specific responses that are likely to be present when the animal is actively engaged in the task. During sleep the short-latency responses in hippocampus are intermingled with sustained activity which in the current experiment was detected for 1-2 seconds.

  5. 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.

  6. Mode of recording and modulation frequency effects of auditory steady state response thresholds

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    Jalaei, Bahram; Shaabani, Moslem; Zakaria, Mohd Normani

    2017-01-01

    Abstract Introduction The performance of auditory steady state response (ASSR) in threshold testing when recorded ipsilaterally and contralaterally, as well as at low and high modulation frequencies (MFs), has not been systematically studied. Objective To verify the influences of mode of recording (ipsilateral vs. contralateral) and modulation frequency (40 Hz vs. 90 Hz) on ASSR thresholds. Methods Fifteen female and 14 male subjects (aged 18–30 years) with normal hearing bilaterally were ...

  7. 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.

  8. 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.

  9. 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.

  10. Psychometric properties of Persian version of the Sustained Auditory Attention Capacity Test in children with attention deficit-hyperactivity disorder.

    Science.gov (United States)

    Soltanparast, Sanaz; Jafari, Zahra; Sameni, Seyed Jalal; Salehi, Masoud

    2014-01-01

    The purpose of the present study was to evaluate the psychometric properties (validity and reliability) of the Persian version of the Sustained Auditory Attention Capacity Test in children with attention deficit hyperactivity disorder. The Persian version of the Sustained Auditory Attention Capacity Test was constructed to assess sustained auditory attention using the method provided by Feniman and colleagues (2007). In this test, comments were provided to assess the child's attentional deficit by determining inattention and impulsiveness error, the total scores of the sustained auditory attention capacity test and attention span reduction index. In the present study for determining the validity and reliability of in both Rey Auditory Verbal Learning test and the Persian version of the Sustained Auditory Attention Capacity Test (SAACT), 46 normal children and 41 children with Attention Deficit Hyperactivity (ADHD), all right-handed and aged between 7 and 11 of both genders, were evaluated. In determining convergent validity, a negative significant correlation was found between the three parts of the Rey Auditory Verbal Learning test (first, fifth, and immediate recall) and all indicators of the SAACT except attention span reduction. By comparing the test scores between the normal and ADHD groups, discriminant validity analysis showed significant differences in all indicators of the test except for attention span reduction (pAttention Capacity test has good validity and reliability, that matches other reliable tests, and it can be used for the identification of children with attention deficits and if they suspected to have Attention Deficit Hyperactivity Disorder.

  11. Auditory responses in the amygdala to social vocalizations

    Science.gov (United States)

    Gadziola, Marie A.

    The underlying goal of this dissertation is to understand how the amygdala, a brain region involved in establishing the emotional significance of sensory input, contributes to the processing of complex sounds. The general hypothesis is that communication calls of big brown bats (Eptesicus fuscus) transmit relevant information about social context that is reflected in the activity of amygdalar neurons. The first specific aim analyzed social vocalizations emitted under a variety of behavioral contexts, and related vocalizations to an objective measure of internal physiological state by monitoring the heart rate of vocalizing bats. These experiments revealed a complex acoustic communication system among big brown bats in which acoustic cues and call structure signal the emotional state of a sender. The second specific aim characterized the responsiveness of single neurons in the basolateral amygdala to a range of social syllables. Neurons typically respond to the majority of tested syllables, but effectively discriminate among vocalizations by varying the response duration. This novel coding strategy underscores the importance of persistent firing in the general functioning of the amygdala. The third specific aim examined the influence of acoustic context by characterizing both the behavioral and neurophysiological responses to natural vocal sequences. Vocal sequences differentially modify the internal affective state of a listening bat, with lower aggression vocalizations evoking the greatest change in heart rate. Amygdalar neurons employ two different coding strategies: low background neurons respond selectively to very few stimuli, whereas high background neurons respond broadly to stimuli but demonstrate variation in response magnitude and timing. Neurons appear to discriminate the valence of stimuli, with aggression sequences evoking robust population-level responses across all sound levels. Further, vocal sequences show improved discrimination among stimuli

  12. 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.

  13. 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

  14. Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma - a prospective study

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    Lau, S K; Wei, W I; Sham, J S.T.; Choy, D T.K.; Hui, Y [Queen Mary Hospital, Hong Kong (Hong Kong)

    1992-10-01

    A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway. (Author).

  15. Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma - a prospective study

    International Nuclear Information System (INIS)

    Lau, S.K.; Wei, W.I.; Sham, J.S.T.; Choy, D.T.K.; Hui, Y.

    1992-01-01

    A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway. (Author)

  16. 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.

  17. 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

  18. The Physiological Basis and Clinical Use of the Binaural Interaction Component of the Auditory Brainstem Response

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    Klump, Georg M.; Tollin, Daniel J.

    2016-01-01

    The auditory brainstem response (ABR) is a sound-evoked non-invasively measured electrical potential representing the sum of neuronal activity in the auditory brainstem and midbrain. ABR peak amplitudes and latencies are widely used in human and animal auditory research and for clinical screening. The binaural interaction component (BIC) of the ABR stands for the difference between the sum of the monaural ABRs and the ABR obtained with binaural stimulation. The BIC comprises a series of distinct waves, the largest of which (DN1) has been used for evaluating binaural hearing in both normal hearing and hearing-impaired listeners. Based on data from animal and human studies, we discuss the possible anatomical and physiological bases of the BIC (DN1 in particular). The effects of electrode placement and stimulus characteristics on the binaurally evoked ABR are evaluated. We review how inter-aural time and intensity differences affect the BIC and, analyzing these dependencies, draw conclusion about the mechanism underlying the generation of the BIC. Finally, the utility of the BIC for clinical diagnoses are summarized. PMID:27232077

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

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    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  7. Auditory color constancy: calibration to reliable spectral properties across nonspeech context and targets.

    Science.gov (United States)

    Stilp, Christian E; Alexander, Joshua M; Kiefte, Michael; Kluender, Keith R

    2010-02-01

    Brief experience with reliable spectral characteristics of a listening context can markedly alter perception of subsequent speech sounds, and parallels have been drawn between auditory compensation for listening context and visual color constancy. In order to better evaluate such an analogy, the generality of acoustic context effects for sounds with spectral-temporal compositions distinct from speech was investigated. Listeners identified nonspeech sounds-extensively edited samples produced by a French horn and a tenor saxophone-following either resynthesized speech or a short passage of music. Preceding contexts were "colored" by spectral envelope difference filters, which were created to emphasize differences between French horn and saxophone spectra. Listeners were more likely to report hearing a saxophone when the stimulus followed a context filtered to emphasize spectral characteristics of the French horn, and vice versa. Despite clear changes in apparent acoustic source, the auditory system calibrated to relatively predictable spectral characteristics of filtered context, differentially affecting perception of subsequent target nonspeech sounds. This calibration to listening context and relative indifference to acoustic sources operates much like visual color constancy, for which reliable properties of the spectrum of illumination are factored out of perception of color.

  8. Is the effect of tinnitus on auditory steady-state response amplitude mediated by attention?

    Directory of Open Access Journals (Sweden)

    Eugen eDiesch

    2012-05-01

    Full Text Available Objectives: The amplitude of the auditory steady-state response (ASSR is enhanced in tinnitus. As ASSR ampli¬tude is also enhanced by attention, the effect of tinnitus on ASSR amplitude could be interpreted as an effect of attention mediated by tinnitus. As attention effects on the N1 are signi¬fi¬cantly larger than those on the ASSR, if the effect of tinnitus on ASSR amplitude were due to attention, there should be similar amplitude enhancement effects in tinnitus for the N1 component of the auditory evoked response. Methods: MEG recordings of auditory evoked responses which were previously examined for the ASSR (Diesch et al. 2010 were analysed with respect to the N1m component. Like the ASSR previously, the N1m was analysed in the source domain (source space projection. Stimuli were amplitude-modulated tones with one of three carrier fre¬quen¬cies matching the tinnitus frequency or a surrogate frequency 1½ octaves above the audio¬metric edge frequency in con¬trols, the audiometric edge frequency, and a frequency below the audio¬metric edgeResults: In the earlier ASSR study (Diesch et al., 2010, the ASSR amplitude in tinnitus patients, but not in controls, was significantly larger in the (surrogate tinnitus condition than in the edge condition. In the present study, both tinnitus patients and healthy controls show an N1m-amplitude profile identical to the one of ASSR amplitudes in healthy controls. N1m amplitudes elicited by tonal frequencies located at the audiometric edge and at the (surrogate tinnitus frequency are smaller than N1m amplitudes elicited by sub-edge tones and do not differ among each other.Conclusions: There is no N1-amplitude enhancement effect in tinnitus. The enhancement effect of tinnitus on ASSR amplitude cannot be accounted for in terms of attention induced by tinnitus.

  9. Linear combination of auditory steady-state responses evoked by co-modulated tones

    DEFF Research Database (Denmark)

    Guérit, François; Marozeau, Jeremy; Epp, Bastian

    2017-01-01

    Up to medium intensities and in the 80–100-Hz region, the auditory steady-state response (ASSR) to a multi-tone carrier is commonly considered to be a linear sum of the dipoles from each tone specific ASSR generator. Here, this hypothesis was investigated when a unique modulation frequency is used...... for all carrier components. Listeners were presented with a co-modulated dual-frequency carrier (1 and 4 kHz), from which the modulator starting phase Ui of the 1-kHz component was systematically varied. The results support the hypothesis of a linear superposition of the dipoles originating from different...

  10. 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...

  11. Enhanced auditory brainstem response and parental bonding style in children with gastrointestinal symptoms.

    Directory of Open Access Journals (Sweden)

    Shizuka Seino

    Full Text Available The electrophysiological properties of the brain and influence of parental bonding in childhood irritable bowel syndrome (IBS are unclear. We hypothesized that children with chronic gastrointestinal (GI symptoms like IBS may show exaggerated brainstem auditory evoked potential (BAEP responses and receive more inadequate parental bonding.Children aged seven and their mothers (141 pairs participated. BAEP was measured by summation of 1,000 waves of the electroencephalogram triggered by 75 dB click sounds. The mothers completed their Children's Somatization Inventory (CSI and Parental Bonding Instrument (PBI. CSI results revealed 66 (42% children without GI symptoms (controls and 75 (58% children with one or more GI symptoms (GI group. The III wave in the GI group (median 4.10 interquartile range [3.95-4.24] ms right, 4.04 [3.90-4.18] ms left had a significantly shorter peak latency than controls (4.18 [4.06-4.34] ms right, p = 0.032, 4.13 [4.02-4.24] ms left, p = 0.018. The female GI group showed a significantly shorter peak latency of the III wave (4.00 [3.90-4.18] ms than controls (4.18 [3.97-4.31] ms, p = 0.034 in the right side. BAEP in the male GI group did not significantly differ from that in controls. GI scores showed a significant correlation with the peak latency of the III wave in the left side (rho = -0.192, p = 0.025. The maternal care PBI scores in the GI group (29 [26]-[33] were significantly lower than controls (31 [28.5-33], p = 0.010, while the maternal over-protection PBI scores were significantly higher in the GI group (16 [12]-[17] than controls (13 [10.5-16], p = 0.024. Multiple regression analysis in females also supported these findings.It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms.

  12. 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.

  13. Electrical Brain Responses to an Auditory Illusion and the Impact of Musical Expertise.

    Science.gov (United States)

    Ioannou, Christos I; Pereda, Ernesto; Lindsen, Job P; Bhattacharya, Joydeep

    2015-01-01

    The presentation of two sinusoidal tones, one to each ear, with a slight frequency mismatch yields an auditory illusion of a beating frequency equal to the frequency difference between the two tones; this is known as binaural beat (BB). The effect of brief BB stimulation on scalp EEG is not conclusively demonstrated. Further, no studies have examined the impact of musical training associated with BB stimulation, yet musicians' brains are often associated with enhanced auditory processing. In this study, we analysed EEG brain responses from two groups, musicians and non-musicians, when stimulated by short presentation (1 min) of binaural beats with beat frequency varying from 1 Hz to 48 Hz. We focused our analysis on alpha and gamma band EEG signals, and they were analysed in terms of spectral power, and functional connectivity as measured by two phase synchrony based measures, phase locking value and phase lag index. Finally, these measures were used to characterize the degree of centrality, segregation and integration of the functional brain network. We found that beat frequencies belonging to alpha band produced the most significant steady-state responses across groups. Further, processing of low frequency (delta, theta, alpha) binaural beats had significant impact on cortical network patterns in the alpha band oscillations. Altogether these results provide a neurophysiological account of cortical responses to BB stimulation at varying frequencies, and demonstrate a modulation of cortico-cortical connectivity in musicians' brains, and further suggest a kind of neuronal entrainment of a linear and nonlinear relationship to the beating frequencies.

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

    Science.gov (United States)

    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

  15. The Effect of Objective Room Acoustic Parameters on Auditory Steady-State Responses

    DEFF Research Database (Denmark)

    Zapata Rodriguez, Valentina; M. Harte, James; Jeong, Cheol-Ho

    2016-01-01

    -state responses (ASSR), recorded in a sound field is a promising technology to verify the hearing aid fitting. The test involves the presentation of the auditory stimuli via a loudspeaker, unlike the usual procedure of delivering via insert earphones. Room reverberation clearly may significantly affect...... the features of the stimulus important for eliciting a strong electrophysiological response, and thus complicate its detection. This study investigates the effect of different room acoustic conditions on recorded ASSRs via an auralisation approach using insert earphones. Fifteen normal-hearing listeners were...... tested using narrow-band (NB) CE-Chirps centered at the octave-bands of 0.5, 1.0, 2.0 and 4.0 kHz. These stimuli were convolved with impulse responses of three rooms simulated using a Green’s function approach to recreate different sound-field conditions. Comparisons with the unmodified stimuli...

  16. Effects of analog and digital filtering on auditory middle latency responses in adults and young children.

    Science.gov (United States)

    Suzuki, T; Hirabayashi, M; Kobayashi, K

    1984-01-01

    Effects of analog high pass (HP) filtering were compared with those of zero phase-shift digital filtering on the auditory middle latency responses (MLR) from nine adults and 16 young children with normal hearing. Analog HP filtering exerted several prominent effects on the MLR waveforms in both adults and young children, such as suppression of Po (ABR), enhancement of Nb, enhancement or emergence of Pb, and latency decrements for Pa and the later components. Analog HP filtering at 20 Hz produced more pronounced waveform distortions in the responses from young children than from adults. Much greater latency decrements for Pa and Nb were observed for young children than for adults in the analog HP-filtered responses at 20 Hz. A large positive peak (Pb) emerged at about 65 ms after the stimulus onset. From these results, the use of digital HP filtering at 20 Hz is strongly recommended for obtaining unbiased and stable MLR in young children.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  20. Auditory laterality in a nocturnal, fossorial marsupial (Lasiorhinus latifrons) in response to bilateral stimuli.

    Science.gov (United States)

    Descovich, K A; Reints Bok, T E; Lisle, A T; Phillips, C J C

    2013-01-01

    Behavioural lateralisation is evident across most animal taxa, although few marsupial and no fossorial species have been studied. Twelve wombats (Lasiorhinus latifrons) were bilaterally presented with eight sounds from different contexts (threat, neutral, food) to test for auditory laterality. Head turns were recorded prior to and immediately following sound presentation. Behaviour was recorded for 150 seconds after presentation. Although sound differentiation was evident by the amount of exploration, vigilance, and grooming performed after different sound types, this did not result in different patterns of head turn direction. Similarly, left-right proportions of head turns, walking events, and food approaches in the post-sound period were comparable across sound types. A comparison of head turns performed before and after sound showed a significant change in turn direction (χ(2) (1)=10.65, p=.001) from a left preference during the pre-sound period (mean 58% left head turns, CI 49-66%) to a right preference in the post-sound (mean 43% left head turns, CI 40-45%). This provides evidence of a right auditory bias in response to the presentation of the sound. This study therefore demonstrates that laterality is evident in southern hairy-nosed wombats in response to a sound stimulus, although side biases were not altered by sounds of varying context.

  1. Development of infant mismatch responses to auditory pattern changes between 2 and 4 months old.

    Science.gov (United States)

    He, Chao; Hotson, Lisa; Trainor, Laurel J

    2009-02-01

    In order to process speech and music, the auditory cortex must learn to process patterns of sounds. Our previous studies showed that with a stream consisting of a repeating (standard) sound, younger infants show an increase in the amplitude of a positive slow wave in response to occasional changes (deviants) in pitch or duration, whereas older infants show a faster negative response that resembles mismatch negativity (MMN) in adults (Trainor et al., 2001, 2003; He et al., 2007). MMN reflects an automatic change-detection process that does not require attention, conscious awareness or behavioural response for its elicitation (Picton et al., 2000; Näätänen et al., 2007). It is an important tool for understanding auditory perception because MMN reflects a change-detection mechanism, and not simply that repetition of a stimulus results in a refractory state of sensory neural circuits while occasional changes to a new sound activate new non-refractory neural circuits (Näätänen et al., 2005). For example, MMN is elicited by a change in the pattern of a repeating note sequence, even when no new notes are introduced that could activate new sensory circuits (Alain et al., 1994, 1999;Schröger et al., 1996). In the present study, we show that in response to a change in the pattern of two repeating tones, MMN in 4-month-olds remains robust whereas the 2-month-old response does not. This indicates that the MMN response to a change in pattern at 4 months reflects the activation of a change-detection mechanism similarly as in adults.

  2. Brainstem auditory responses to resolved and unresolved harmonics of a synthetic vowel in quiet and noise.

    Science.gov (United States)

    Laroche, Marilyn; Dajani, Hilmi R; Prévost, François; Marcoux, André M

    2013-01-01

    This study investigated speech auditory brainstem responses (speech ABR) with variants of a synthetic vowel in quiet and in background noise. Its objectives were to study the noise robustness of the brainstem response at the fundamental frequency F0 and at the first formant F1, evaluate how the resolved/unresolved harmonics regions in speech contribute to the response at F0, and investigate the origin of the response at F0 to resolved and unresolved harmonics in speech. In total, 18 normal-hearing subjects (11 women, aged 18-33 years) participated in this study. Speech ABRs were recorded using variants of a 300 msec formant-synthesized /a/ vowel in quiet and in white noise. The first experiment employed three variants containing the first three formants F1 to F3, F1 only, and F2 and F3 only with relative formant levels following those reported in the literature. The second experiment employed three variants containing F1 only, F2 only, and F3 only, with the formants equalized to the same level and the signal-to-noise ratio (SNR) maintained at -5 dB. Overall response latency was estimated, and the amplitude and local SNR of the envelope following response at F0 and of the frequency following response at F1 were compared for the different stimulus variants in quiet and in noise. The response at F0 was more robust to noise than that at F1. There were no statistically significant differences in the response at F0 caused by the three stimulus variants in both experiments in quiet. However, the response at F0 with the variant dominated by resolved harmonics was more robust to noise than the response at F0 with the stimulus variants dominated by unresolved harmonics. The latencies of the responses in all cases were very similar in quiet, but the responses at F0 due to resolved and unresolved harmonics combined nonlinearly when both were present in the stimulus. Speech ABR has been suggested as a marker of central auditory processing. The results of this study support

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

    Science.gov (United States)

    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.

  4. Property Rights, Restrictions and Responsibilities

    DEFF Research Database (Denmark)

    Enemark, Stig

    more to a social, ethical commitment or attitude to environmental sustainability and good husbandry. This paper provides an overall understanding of the concept of land administration systems for dealing with rights, restrictions and responsibilities in future spatially enabled government. Finally......Land Administration Systems are the basis for conceptualizing rights, restrictions and responsibilities related to people, policies and places. Property rights are normally concerned with ownership and tenure whereas restrictions usually control use and activities on land. Responsibilities relate...

  5. Correlation of auditory brain stem response and the MRI measurements in neuro-degenerative disorders

    International Nuclear Information System (INIS)

    Kamei, Hidekazu

    1989-01-01

    The purpose of this study is to elucidate correlations of several MRI measurements of the cranium and brain, functioning as a volume conductor, to the auditory brain stem response (ABR) in neuro-degenerative disorders. The subjects included forty-seven patients with spinocerebellar degeneration (SCD) and sixteen of amyotrophic lateral sclerosis (ALS). Statistically significant positive correlations were found between I-V and III-V interpeak latencies (IPLs) and the area of cranium and brain in the longitudinal section of SCD patients, and between I-III and III-V IPLs and the area in the longitudinal section of those with ALS. And, also there were statistically significant correlations between the amplitude of the V wave and the area of brain stem as well as that of the cranium in the longitudinal section of SCD patients, and between the amplitude of the V wave and the area of the cerebrum in the longitudinal section of ALS. In conclusion, in the ABR, the IPLs were prolonged and the amplitude of the V wave was decreased while the MRI size of the cranium and brain increased. When the ABR is applied to neuro-degenerative disorders, it might be important to consider not only the conduction of the auditory tracts in the brain stem, but also the correlations of the size of the cranium and brain which act as a volume conductor. (author)

  6. Correlation of auditory brain stem response and the MRI measurements in neuro-degenerative disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Hidekazu (Tokyo Women' s Medical Coll. (Japan))

    1989-06-01

    The purpose of this study is to elucidate correlations of several MRI measurements of the cranium and brain, functioning as a volume conductor, to the auditory brain stem response (ABR) in neuro-degenerative disorders. The subjects included forty-seven patients with spinocerebellar degeneration (SCD) and sixteen of amyotrophic lateral sclerosis (ALS). Statistically significant positive correlations were found between I-V and III-V interpeak latencies (IPLs) and the area of cranium and brain in the longitudinal section of SCD patients, and between I-III and III-V IPLs and the area in the longitudinal section of those with ALS. And, also there were statistically significant correlations between the amplitude of the V wave and the area of brain stem as well as that of the cranium in the longitudinal section of SCD patients, and between the amplitude of the V wave and the area of the cerebrum in the longitudinal section of ALS. In conclusion, in the ABR, the IPLs were prolonged and the amplitude of the V wave was decreased while the MRI size of the cranium and brain increased. When the ABR is applied to neuro-degenerative disorders, it might be important to consider not only the conduction of the auditory tracts in the brain stem, but also the correlations of the size of the cranium and brain which act as a volume conductor. (author).

  7. Auditory properties in the parabelt regions of the superior temporal gyrus in the awake macaque monkey: an initial survey.

    Science.gov (United States)

    Kajikawa, Yoshinao; Frey, Stephen; Ross, Deborah; Falchier, Arnaud; Hackett, Troy A; Schroeder, Charles E

    2015-03-11

    The superior temporal gyrus (STG) is on the inferior-lateral brain surface near the external ear. In macaques, 2/3 of the STG is occupied by an auditory cortical region, the "parabelt," which is part of a network of inferior temporal areas subserving communication and social cognition as well as object recognition and other functions. However, due to its location beneath the squamous temporal bone and temporalis muscle, the STG, like other inferior temporal regions, has been a challenging target for physiological studies in awake-behaving macaques. We designed a new procedure for implanting recording chambers to provide direct access to the STG, allowing us to evaluate neuronal properties and their topography across the full extent of the STG in awake-behaving macaques. Initial surveys of the STG have yielded several new findings. Unexpectedly, STG sites in monkeys that were listening passively responded to tones with magnitudes comparable to those of responses to 1/3 octave band-pass noise. Mapping results showed longer response latencies in more rostral sites and possible tonotopic patterns parallel to core and belt areas, suggesting the reversal of gradients between caudal and rostral parabelt areas. These results will help further exploration of parabelt areas. Copyright © 2015 the authors 0270-6474/15/354140-11$15.00/0.

  8. 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.

  9. Electrical Brain Responses to an Auditory Illusion and the Impact of Musical Expertise.

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    Christos I Ioannou

    Full Text Available The presentation of two sinusoidal tones, one to each ear, with a slight frequency mismatch yields an auditory illusion of a beating frequency equal to the frequency difference between the two tones; this is known as binaural beat (BB. The effect of brief BB stimulation on scalp EEG is not conclusively demonstrated. Further, no studies have examined the impact of musical training associated with BB stimulation, yet musicians' brains are often associated with enhanced auditory processing. In this study, we analysed EEG brain responses from two groups, musicians and non-musicians, when stimulated by short presentation (1 min of binaural beats with beat frequency varying from 1 Hz to 48 Hz. We focused our analysis on alpha and gamma band EEG signals, and they were analysed in terms of spectral power, and functional connectivity as measured by two phase synchrony based measures, phase locking value and phase lag index. Finally, these measures were used to characterize the degree of centrality, segregation and integration of the functional brain network. We found that beat frequencies belonging to alpha band produced the most significant steady-state responses across groups. Further, processing of low frequency (delta, theta, alpha binaural beats had significant impact on cortical network patterns in the alpha band oscillations. Altogether these results provide a neurophysiological account of cortical responses to BB stimulation at varying frequencies, and demonstrate a modulation of cortico-cortical connectivity in musicians' brains, and further suggest a kind of neuronal entrainment of a linear and nonlinear relationship to the beating frequencies.

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

    Science.gov (United States)

    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.

  11. Abnormal Auditory Brainstem Response (ABR Findings in a Near-Normal Hearing Child with Noonan Syndrome

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    Bahram Jalaei

    2017-01-01

    Full Text Available Introduction: Noonan syndrome (NS is a heterogeneous genetic disease that affects many parts of the body. It was named after Dr. Jacqueline Anne Noonan, a paediatric cardiologist.Case Report: We report audiological tests and auditory brainstem response (ABR findings in a 5-year old Malay boy with NS. Despite showing the marked signs of NS, the child could only produce a few meaningful words. Audiological tests found him to have bilateral mild conductive hearing loss at low frequencies. In ABR testing, despite having good waveform morphology, the results were atypical. Absolute latency of wave V was normal but interpeak latencies of wave’s I-V, I-II, II-III were prolonged. Interestingly, interpeak latency of waves III-V was abnormally shorter.Conclusion:Abnormal ABR results are possibly due to abnormal anatomical condition of brainstem and might contribute to speech delay.

  12. Clinical Experience of Auditory Brainstem Response Testing on Pediatric Patients in the Operating Room

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    Guangwei Zhou

    2012-01-01

    Full Text Available Objectives. To review our experience of conducting auditory brainstem response (ABR test on children in the operating room and discuss the benefits versus limitations of this practice. Methods. Retrospective review study conducted in a pediatric tertiary care facility. A total of 267 patients identified with usable data, including ABR results, medical and surgical notes, and follow-up evaluation. Results. Hearing status successfully determined in all patients based on the ABR results form the operating room. The degrees and the types of hearing loss also documented in most of the cases. In addition, multiple factors that may affect the outcomes of ABR in the operating room identified. Conclusions. Hearing loss in children with complicated medical issues can be accurately evaluated via ABR testing in the operating room. Efforts should be made to eliminate adverse factors to ABR recording, and caution should be taken when interpreting ABR results from the operating room.

  13. Dissociable neural response signatures for slow amplitude and frequency modulation in human auditory cortex.

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    Henry, Molly J; Obleser, Jonas

    2013-01-01

    Natural auditory stimuli are characterized by slow fluctuations in amplitude and frequency. However, the degree to which the neural responses to slow amplitude modulation (AM) and frequency modulation (FM) are capable of conveying independent time-varying information, particularly with respect to speech communication, is unclear. In the current electroencephalography (EEG) study, participants listened to amplitude- and frequency-modulated narrow-band noises with a 3-Hz modulation rate, and the resulting neural responses were compared. Spectral analyses revealed similar spectral amplitude peaks for AM and FM at the stimulation frequency (3 Hz), but amplitude at the second harmonic frequency (6 Hz) was much higher for FM than for AM. Moreover, the phase delay of neural responses with respect to the full-band stimulus envelope was shorter for FM than for AM. Finally, the critical analysis involved classification of single trials as being in response to either AM or FM based on either phase or amplitude information. Time-varying phase, but not amplitude, was sufficient to accurately classify AM and FM stimuli based on single-trial neural responses. Taken together, the current results support the dissociable nature of cortical signatures of slow AM and FM. These cortical signatures potentially provide an efficient means to dissect simultaneously communicated slow temporal and spectral information in acoustic communication signals.

  14. Thresholds of Tone Burst Auditory Brainstem Responses for Infants and Young Children with Normal Hearing in Taiwan

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    Chung-Yi Lee

    2007-10-01

    Conclusion: Based on the published research and our study, we suggest setting the normal criterion levels for infants and young children in Taiwan of the tone burst auditory brainstem response to air-conducted tones as 30 dB nHL for 500 and 1000 Hz, and 25 dB nHL for 2000 and 4000 Hz.

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

    Science.gov (United States)

    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.

  16. 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.

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

    Science.gov (United States)

    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

  18. Auditory-visual integration in fields of the auditory cortex.

    Science.gov (United States)

    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.

  19. Effects of ZNF804A on auditory P300 response in schizophrenia.

    LENUS (Irish Health Repository)

    O'Donoghue, T

    2014-01-01

    The common variant rs1344706 within the zinc-finger protein gene ZNF804A has been strongly implicated in schizophrenia (SZ) susceptibility by a series of recent genetic association studies. Although associated with a pattern of altered neural connectivity, evidence that increased risk is mediated by an effect on cognitive deficits associated with the disorder has been equivocal. This study investigated whether the same ZNF804A risk allele was associated with variation in the P300 auditory-evoked response, a cognitively relevant putative endophenotype for SZ. We compared P300 responses in carriers and noncarriers of the ZNF804A risk allele genotype groups in Irish patients and controls (n=97). P300 response was observed to vary according to genotype in this sample, such that risk allele carriers showed relatively higher P300 response compared with noncarriers. This finding accords with behavioural data reported by our group and others. It is also consistent with the idea that ZNF804A may have an impact on cortical efficiency, reflected in the higher levels of activations required to achieve comparable behavioural accuracy on the task used.

  20. Auditory brainstem response in neonates: influence of gender and weight/gestational age ratio

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    Rosanna M. Giaffredo Angrisani

    2013-12-01

    Full Text Available OBJECTIVE: To investigate the influence of gender and weight/gestational age ratio on the Auditory Brainstem Response (ABR in preterm (PT and term (T newborns. METHODS: 176 newborns were evaluated by ABR; 88 were preterm infants - 44 females (22 small and 22 appropriate for gestational age and 44 males (22 small and 22 appropriate for gestational age. The preterm infants were compared to 88 term infants - 44 females (22 small and 22 appropriate for gestational age and 44 males (22 small and 22 appropriate for gestational age. All newborns had bilateral presence of transient otoacoustic emissions and type A tympanometry. RESULTS: No interaural differences were found. ABR response did not differentiate newborns regarding weight/gestational age in males and females. Term newborn females showed statistically shorter absolute latencies (except on wave I than males. This finding did not occur in preterm infants, who had longer latencies than term newborns, regardless of gender. CONCLUSIONS: Gender and gestational age influence term infants' ABR, with lower responses in females. The weight/gestational age ratio did not influence ABR response in either groups.

  1. Auditory Magnetoencephalographic Frequency-Tagged Responses Mirror the Ongoing Segmentation Processes Underlying Statistical Learning.

    Science.gov (United States)

    Farthouat, Juliane; Franco, Ana; Mary, Alison; Delpouve, Julie; Wens, Vincent; Op de Beeck, Marc; De Tiège, Xavier; Peigneux, Philippe

    2017-03-01

    Humans are highly sensitive to statistical regularities in their environment. This phenomenon, usually referred as statistical learning, is most often assessed using post-learning behavioural measures that are limited by a lack of sensibility and do not monitor the temporal dynamics of learning. In the present study, we used magnetoencephalographic frequency-tagged responses to investigate the neural sources and temporal development of the ongoing brain activity that supports the detection of regularities embedded in auditory streams. Participants passively listened to statistical streams in which tones were grouped as triplets, and to random streams in which tones were randomly presented. Results show that during exposure to statistical (vs. random) streams, tritone frequency-related responses reflecting the learning of regularities embedded in the stream increased in the left supplementary motor area and left posterior superior temporal sulcus (pSTS), whereas tone frequency-related responses decreased in the right angular gyrus and right pSTS. Tritone frequency-related responses rapidly developed to reach significance after 3 min of exposure. These results suggest that the incidental extraction of novel regularities is subtended by a gradual shift from rhythmic activity reflecting individual tone succession toward rhythmic activity synchronised with triplet presentation, and that these rhythmic processes are subtended by distinct neural sources.

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

    Science.gov (United States)

    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.

  3. Noise Stress Induces an Epidermal Growth Factor Receptor/Xeroderma Pigmentosum-A Response in the Auditory Nerve.

    Science.gov (United States)

    Guthrie, O'neil W

    2017-03-01

    In response to toxic stressors, cancer cells defend themselves by mobilizing one or more epidermal growth factor receptor (EGFR) cascades that employ xeroderma pigmentosum-A (XPA) to repair damaged genes. Recent experiments discovered that neurons within the auditory nerve exhibit basal levels of EGFR+XPA co-expression. This finding implied that auditory neurons in particular or neurons in general have the capacity to mobilize an EGFR+XPA defense. Therefore, the current study tested the hypothesis that noise stress would alter the expression pattern of EGFR/XPA within the auditory nerve. Design-based stereology was used to quantify the proportion of neurons that expressed EGFR, XPA, and EGFR+XPA with and without noise stress. The results revealed an intricate neuronal response that is suggestive of alterations to both co-expression and individual expression of EGFR and XPA. In both the apical and middle cochlear coils, the noise stress depleted EGFR+XPA expression. Furthermore, there was a reduction in the proportion of neurons that expressed XPA-alone in the middle coils. However, the noise stress caused a significant increase in the proportion of neurons that expressed EGFR-alone in the middle coils. The basal cochlear coils failed to mobilize a significant response to the noise stress. These results suggest that EGFR and XPA might be part of the molecular defense repertoire of the auditory nerve.

  4. Noise Stress Induces an Epidermal Growth Factor Receptor/Xeroderma Pigmentosum–A Response in the Auditory Nerve

    Science.gov (United States)

    Guthrie, O’neil W.

    2017-01-01

    In response to toxic stressors, cancer cells defend themselves by mobilizing one or more epidermal growth factor receptor (EGFR) cascades that employ xeroderma pigmentosum–A (XPA) to repair damaged genes. Recent experiments discovered that neurons within the auditory nerve exhibit basal levels of EGFR+XPA co-expression. This finding implied that auditory neurons in particular or neurons in general have the capacity to mobilize an EGFR+XPA defense. Therefore, the current study tested the hypothesis that noise stress would alter the expression pattern of EGFR/XPA within the auditory nerve. Design-based stereology was used to quantify the proportion of neurons that expressed EGFR, XPA, and EGFR+XPA with and without noise stress. The results revealed an intricate neuronal response that is suggestive of alterations to both co-expression and individual expression of EGFR and XPA. In both the apical and middle cochlear coils, the noise stress depleted EGFR+XPA expression. Furthermore, there was a reduction in the proportion of neurons that expressed XPA-alone in the middle coils. However, the noise stress caused a significant increase in the proportion of neurons that expressed EGFR-alone in the middle coils. The basal cochlear coils failed to mobilize a significant response to the noise stress. These results suggest that EGFR and XPA might be part of the molecular defense repertoire of the auditory nerve. PMID:28056182

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

    Science.gov (United States)

    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.

  6. Synchronized Progression of Prestin Expression and Auditory Brainstem Response during Postnatal Development in Rats

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    Jianfeng Hang

    2016-01-01

    Full Text Available Prestin is the motor protein expressed in the cochlear outer hair cells (OHCs of mammalian inner ear. The electromotility of OHCs driven by prestin is responsible for the cochlear amplification which is required for normal hearing in adult animals. Postnatal expression of prestin and activity of OHCs may contribute to the maturation of hearing in rodents. However, the temporal and spatial expression of prestin in cochlea during the development is not well characterized. In the present study, we examined the expression and function of prestin from the OHCs in apical, middle, and basal turns of the cochleae of postnatal rats. Prestin first appeared at postnatal day 6 (P6 for basal turn, P7 in middle turn, and P9 for apical turn of cochlea. The expression level increased progressively over the next few days and by P14 reached the mature level for all three segments. By comparison with the time course of the development of auditory brainstem response for different frequencies, our data reveal that prestin expression synchronized with the hearing development. The present study suggests that the onset time of hearing may require the expression of prestin and is determined by the mature function of OHCs.

  7. Using Auditory Steady-State Responses for Measuring Hearing Protector Attenuation

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    Olivier Valentin

    2017-01-01

    Full Text Available Introduction: Present methods of measuring the attenuation of hearing protection devices (HPDs have limitations. Objective measurements such as field microphone in real-ear do not assess bone-conducted sound. Psychophysical measurements such as real-ear attenuation at threshold (REAT are biased due to the low frequency masking effects from test subjects’ physiological noise and the variability of measurements based on subjective responses. An auditory steady-state responses (ASSRs procedure is explored as a technique which might overcome these limitations. Subjects and Methods: Pure tone stimuli (500 and 1000 Hz, amplitude modulated at 40 Hz, are presented to 10 normal-hearing adults through headphones at three levels in 10 dB steps. Two conditions were assessed: unoccluded ear canal and occluded ear canal. ASSR amplitude data as a function of the stimulation level are linearized using least-square regressions. The “physiological attenuation” is then calculated as the average difference between the two measurements. The technical feasibility of measuring earplug attenuation is demonstrated for the group average attenuation across subjects. Results: No significant statistical difference is found between the average REAT attenuation and the average ASSR-based attenuation. Conclusion: Feasibility is not yet demonstrated for individual subjects since differences between the estimates occurred for some subjects.

  8. Analog and digital filtering of the brain stem auditory evoked response.

    Science.gov (United States)

    Kavanagh, K T; Franks, R

    1989-07-01

    This study compared the filtering effects on the auditory evoked potential of zero and standard phase shift digital filters (the former was a mathematical approximation of a standard Butterworth filter). Conventional filters were found to decrease the height of the evoked response in the majority of waveforms compared to zero phase shift filters. A 36-dB/octave zero phase shift high pass filter with a cutoff frequency of 100 Hz produced a 16% reduction in wave amplitude compared to the unfiltered control. A 36-dB/octave, 100-Hz standard phase shift high pass filter produced a 41% reduction, and a 12-dB/octave, 150-Hz standard phase shift high pass filter produced a 38% reduction in wave amplitude compared to the unfiltered control. A decrease in the mean along with an increase in the variability of wave IV/V latency was also noted with conventional compared to zero phase shift filters. The increase in the variability of the latency measurement was due to the difficulty in waveform identification caused by the phase shift distortion of the conventional filter along with the variable decrease in wave latency caused by phase shifting responses with different spectral content. Our results indicated that a zero phase shift high pass filter of 100 Hz was the most desirable filter studied for the mitigation of spontaneous brain activity and random muscle artifact.

  9. The effectiveness of familiar auditory stimulus on hospitalized neonates' physiologic responses to procedural pain.

    Science.gov (United States)

    Azarmnejad, Elham; Sarhangi, Forogh; Javadi, Mahrooz; Rejeh, Nahid; Amirsalari, Susan; Tadrisi, Seyed Davood

    2017-06-01

    Hospitalized neonates usually undergo different painful procedures. This study sought to test the effects of a familiar auditory stimulus on the physiologic responses to pain of venipuncture among neonates in intensive care unit. The study design is quasi-experimental. The randomized clinical trial study was done on 60 full-term neonates admitted to the neonatal intensive care unit between March 20 to June 20, 2014. The neonates were conveniently selected and randomly allocated to the control and the experimental groups. Recorded maternal voice was played for the neonates in the experimental group from 10 minutes before to 10 minutes after venipuncture while the neonates in the control group received no sound therapy intervention. The participants' physiologic parameters were assessed 10 minutes before, during, and after venipuncture. At baseline, the study groups did not differ significantly regarding the intended physiologic parameters (P > .05). During venipuncture, maternal voice was effective in reducing the neonates' heart rate, respiratory rate, and diastolic blood pressure (P familiar sounds to effectively manage neonates' physiologic responses to procedural pain of venipuncture. © 2017 John Wiley & Sons Australia, Ltd.

  10. The paced auditory serial addition test for working memory assessment: Psychometric properties

    Science.gov (United States)

    Nikravesh, Maryam; Jafari, Zahra; Mehrpour, Masoud; Kazemi, Roozbeh; Amiri Shavaki, Younes; Hossienifar, Shamim; Azizi, Mohamad Parsa

    2017-01-01

    Background: The paced auditory serial addition test (PASAT) was primarily developed to assess the effects of traumatic brain injury on cognitive functioning. Working memory (WM) is one of the most important aspects of cognitive function, and WM impairment is one of the clinically remarkable signs of aphasia. To develop the Persian version of PASAT, an initial version was used in individuals with aphasia (IWA). Methods: In this study, 25 individuals with aphasia (29-60 years) and 85 controls (18-60 years) were included. PASAT was presented in the form of recorded 61 single-digit numbers (1 to 9). The participants repeatedly added the 2 recent digits. The psychometric properties of PASAT including convergent validity (using the digit memory span tasks), divergent validity (using results in the control group and IWA group), and face validity were investigated. Test-retest reliability was considered as well. Results: The relationship between the PASAT and digit memory span tests was moderate to strong in the control group (forward digit memory span test: r= 0.52, p< 0.0001; backward digit memory span test: r = 0.48, p< 0.0001). A strong relationship was found in IWA (forward digit memory span test: r= 0.72, p< 0.0001; backward digit memory span test: r= 0.53, p= 0.006). Also, strong testretest reliability (intraclass correlation= 0.95, p< 0.0001) was observed. Conclusion: According to our results, the PASAT is a valid and reliable test to assess working memory, particularly in IWA. It could be used as a feasible tool for clinical and research applications. PMID:29445690

  11. Auditory stimulation with music influences the geometric indices of heart rate variability in response to the postural change maneuver.

    Science.gov (United States)

    de Castro, Bianca C R; Guida, Heraldo L; Roque, Adriano L; de Abreu, Luiz Carlos; Ferreira, Celso; Marcomini, Renata S; Monteiro, Carlos B M; Adami, Fernando; Ribeiro, Viviane F; Fonseca, Fernando L A; Santos, Vilma N S; Valenti, Vitor E

    2014-01-01

    It is poor in the literature the behavior of the geometric indices of heart rate variability (HRV) during the musical auditory stimulation. The objective is to investigate the acute effects of classic musical auditory stimulation on the geometric indexes of HRV in women in response to the postural change maneuver (PCM). We evaluated 11 healthy women between 18 and 25 years old. We analyzed the following indices: Triangular index, Triangular interpolation of RR intervals and Poincarι plot (standard deviation of the instantaneous variability of the beat-to beat heart rate [SD1], standard deviation of long-term continuous RR interval variability and Ratio between the short - and long-term variations of RR intervals [SD1/SD2] ratio). HRV was recorded at seated rest for 10 min. The women quickly stood up from a seated position in up to 3 s and remained standing still for 15 min. HRV was recorded at the following periods: Rest, 0-5 min, 5-10 min and 10-15 min during standing. In the second protocol, the subject was exposed to auditory musical stimulation (Pachelbel-Canon in D) for 10 min at seated position before standing position. Shapiro-Wilk to verify normality of data and ANOVA for repeated measures followed by the Bonferroni test for parametric variables and Friedman's followed by the Dunn's posttest for non-parametric distributions. In the first protocol, all indices were reduced at 10-15 min after the volunteers stood up. In the protocol musical auditory stimulation, the SD1 index was reduced at 5-10 min after the volunteers stood up compared with the music period. The SD1/SD2 ratio was decreased at control and music period compared with 5-10 min after the volunteers stood up. Musical auditory stimulation attenuates the cardiac autonomic responses to the PCM.

  12. Auditory stimulation with music influences the geometric indices of heart rate variability in response to the postural change maneuver

    Directory of Open Access Journals (Sweden)

    Bianca C. R. de Castro

    2014-01-01

    Full Text Available It is poor in the literature the behavior of the geometric indices of heart rate variability (HRV during the musical auditory stimulation. The objective is to investigate the acute effects of classic musical auditory stimulation on the geometric indexes of HRV in women in response to the postural change maneuver (PCM. We evaluated 11 healthy women between 18 and 25 years old. We analyzed the following indices: Triangular index, Triangular interpolation of RR intervals and Poincarι plot (standard deviation of the instantaneous variability of the beat-to beat heart rate [SD1], standard deviation of long-term continuous RR interval variability and Ratio between the short - and long-term variations of RR intervals [SD1/SD2] ratio. HRV was recorded at seated rest for 10 min. The women quickly stood up from a seated position in up to 3 s and remained standing still for 15 min. HRV was recorded at the following periods: Rest, 0-5 min, 5-10 min and 10-15 min during standing. In the second protocol, the subject was exposed to auditory musical stimulation (Pachelbel-Canon in D for 10 min at seated position before standing position. Shapiro-Wilk to verify normality of data and ANOVA for repeated measures followed by the Bonferroni test for parametric variables and Friedman′s followed by the Dunn′s posttest for non-parametric distributions. In the first protocol, all indices were reduced at 10-15 min after the volunteers stood up. In the protocol musical auditory stimulation, the SD1 index was reduced at 5-10 min after the volunteers stood up compared with the music period. The SD1/SD2 ratio was decreased at control and music period compared with 5-10 min after the volunteers stood up. Musical auditory stimulation attenuates the cardiac autonomic responses to the PCM.

  13. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation.

    Science.gov (United States)

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders; Fedder, Jens; Laurberg, Peter; Østergaard, John R; Hertz, Jens Michael; Pedersen, Anders Degn; Gravholt, Claus Højbjerg

    2016-01-01

    Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49) responded to whether the words "GREEN" or "RED" were displayed in green or red (incongruent versus congruent colors). One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying "GREEN" or "RED" had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  14. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    Directory of Open Access Journals (Sweden)

    Mikkel Wallentin

    2016-01-01

    Full Text Available Klinefelter syndrome (47, XXY (KS is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49 responded to whether the words “GREEN” or “RED” were displayed in green or red (incongruent versus congruent colors. One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying “GREEN” or “RED” had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  15. Auditory brainstem response screening for hearing loss in high risk neonates.

    Science.gov (United States)

    Watson, D R; McClelland, R J; Adams, D A

    1996-07-01

    The present paper reports the findings of a 7 year study evaluating the use of the auditory brainstem response (ABR) as the basis of a hearing screening procedure in a group of newborns at increased risk of hearing impairment. A Special Care Baby Unit (SCBU) population of 417 infants with diverse clinical backgrounds and treatment histories was tested for hearing impairment at birth using ABR audiometry. Some 332 passed the original screen at 30 dBnHL test level in both ears. Of the failure group, 18 did not survive and 32 had some degree of hearing impairment confirmed, nine of which were sensorineural in origin. An increased incidence of persistent middle ear disease was also noted in the failure group. A detailed operational analysis demonstrates that provided appropriate pass/fail criteria are adopted, the ABR technique offers excellent sensitivity and specificity for the detection of significant hearing loss in the test population. Furthermore, the study establishes that implementation of an ABR-based screening programme could reduce the average age at detection of permanent hearing loss by 7 months. A cost assessment shows that the introduction of such a targetted screening procedure could be done at a reasonable outlay.

  16. Development of a Chirp Stimulus PC-Based Auditory Brainstem Response Audiometer

    Directory of Open Access Journals (Sweden)

    Ali AL-Afsaa

    2004-05-01

    Full Text Available Hearing losses during infancy and childhood have many negative future effects and impacts on the child life and productivity. The earlier detection of hearing losses, the earlier medical intervention and then the greater benefit of remediation will be. During this research a PC-based audiometer is designed and, currently, the audiometer prototype is in its final development steps. It is based on the auditory brainstem response (ABR method. Chirp stimuli instead of traditional click stimuli will be used to invoke the ABR signal. The stimulus is designed to synchronize the hair cells movement when it spreads out over the cochlea. In addition to the available hardware utilization (PC and PCI board, the efforts confined to design and implement a hardware prototype and to develop a software package that enables the system to behave as ABR audiometer. By using such a method and chirp stimulus, it is expected to be able to detect hearing impairment (sensorineural in the first few days of the life and conduct hearing test at low frequency of stimulus. Currently, the intended chirp stimulus has been successfully generated and the implemented module is able to amplify a signal (on the order of ABR signal to a recordable level. Moreover, a NI-DAQ data acquisition board has been chosen to implement the PC-prototype interface.

  17. Auditory Steady-State Response Thresholds in Adults With Conductive and Mild to Moderate Sensorineural Hearing Loss

    OpenAIRE

    Hosseinabadi, Reza; Jafarzadeh, Sadegh

    2014-01-01

    Background: The Auditory steady state response (ASSR) provides a frequency-specific and automatic assessment of hearing sensitivity and is used in infants and difficult-to-test adults. Objectives: The aim of this study was to compare the ASSR thresholds among various types (normal, conductive, and sensorineural), degree (normal, mild, and moderate), and configuration (flat and sloping) of hearing sensitivity, and measuring the cutoff point between normal condition and hearing loss for differe...

  18. Evaluation of a Loudspeaker-Based Virtual Acoustic Environment for Investigating sound-field auditory steady-state responses

    DEFF Research Database (Denmark)

    Zapata-Rodriguez, Valentina; Marbjerg, Gerd Høy; Brunskog, Jonas

    2017-01-01

    Measuring sound-field auditory steady-state responses (ASSR) is a promising new objective clinical procedure for hearing aid fitting validation, particularly for infants who cannot respond to behavioral tests. In practice, room acoustics of non-anechoic test rooms can heavily influence the audito...... tool PARISM (Phased Acoustical Radiosity and Image Source Method) and validated through measurements. This study discusses the limitations of the system and the potential improvements needed for a more realistic sound-field ASSR simulation....

  19. High-density EEG characterization of brain responses to auditory rhythmic stimuli during wakefulness and NREM sleep.

    Science.gov (United States)

    Lustenberger, Caroline; Patel, Yogi A; Alagapan, Sankaraleengam; Page, Jessica M; Price, Betsy; Boyle, Michael R; Fröhlich, Flavio

    2018-04-01

    Auditory rhythmic sensory stimulation modulates brain oscillations by increasing phase-locking to the temporal structure of the stimuli and by increasing the power of specific frequency bands, resulting in Auditory Steady State Responses (ASSR). The ASSR is altered in different diseases of the central nervous system such as schizophrenia. However, in order to use the ASSR as biological markers for disease states, it needs to be understood how different vigilance states and underlying brain activity affect the ASSR. Here, we compared the effects of auditory rhythmic stimuli on EEG brain activity during wake and NREM sleep, investigated the influence of the presence of dominant sleep rhythms on the ASSR, and delineated the topographical distribution of these modulations. Participants (14 healthy males, 20-33 years) completed on the same day a 60 min nap session and two 30 min wakefulness sessions (before and after the nap). During these sessions, amplitude modulated (AM) white noise auditory stimuli at different frequencies were applied. High-density EEG was continuously recorded and time-frequency analyses were performed to assess ASSR during wakefulness and NREM periods. Our analysis revealed that depending on the electrode location, stimulation frequency applied and window/frequencies analysed the ASSR was significantly modulated by sleep pressure (before and after sleep), vigilance state (wake vs. NREM sleep), and the presence of slow wave activity and sleep spindles. Furthermore, AM stimuli increased spindle activity during NREM sleep but not during wakefulness. Thus, (1) electrode location, sleep history, vigilance state and ongoing brain activity needs to be carefully considered when investigating ASSR and (2) auditory rhythmic stimuli during sleep might represent a powerful tool to boost sleep spindles. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Comparisons of memory for nonverbal auditory and visual sequential stimuli.

    Science.gov (United States)

    McFarland, D J; Cacace, A T

    1995-01-01

    Properties of auditory and visual sensory memory were compared by examining subjects' recognition performance of randomly generated binary auditory sequential frequency patterns and binary visual sequential color patterns within a forced-choice paradigm. Experiment 1 demonstrated serial-position effects in auditory and visual modalities consisting of both primacy and recency effects. Experiment 2 found that retention of auditory and visual information was remarkably similar when assessed across a 10s interval. Experiments 3 and 4, taken together, showed that the recency effect in sensory memory is affected more by the type of response required (recognition vs. reproduction) than by the sensory modality employed. These studies suggest that auditory and visual sensory memory stores for nonverbal stimuli share similar properties with respect to serial-position effects and persistence over time.

  1. Binaural Interaction Effects of 30-50 Hz Auditory Steady State Responses.

    Science.gov (United States)

    Gransier, Robin; van Wieringen, Astrid; Wouters, Jan

    Auditory stimuli modulated by modulation frequencies within the 30 to 50 Hz region evoke auditory steady state responses (ASSRs) with high signal to noise ratios in adults, and can be used to determine the frequency-specific hearing thresholds of adults who are unable to give behavioral feedback reliably. To measure ASSRs as efficiently as possible a multiple stimulus paradigm can be used, stimulating both ears simultaneously. The response strength of 30 to 50Hz ASSRs is, however, affected when both ears are stimulated simultaneously. The aim of the present study is to gain insight in the measurement efficiency of 30 to 50 Hz ASSRs evoked with a 2-ear stimulation paradigm, by systematically investigating the binaural interaction effects of 30 to 50 Hz ASSRs in normal-hearing adults. ASSRs were obtained with a 64-channel EEG system in 23 normal-hearing adults. All participants participated in one diotic, multiple dichotic, and multiple monaural conditions. Stimuli consisted of a modulated one-octave noise band, centered at 1 kHz, and presented at 70 dB SPL. The diotic condition contained 40 Hz modulated stimuli presented to both ears. In the dichotic conditions, the modulation frequency of the left ear stimulus was kept constant at 40 Hz, while the stimulus at the right ear was either the unmodulated or modulated carrier. In case of the modulated carrier, the modulation frequency varied between 30 and 50 Hz in steps of 2 Hz across conditions. The monaural conditions consisted of all stimuli included in the diotic and dichotic conditions. Modulation frequencies ≥36 Hz resulted in prominent ASSRs in all participants for the monaural conditions. A significant enhancement effect was observed (average: ~3 dB) in the diotic condition, whereas a significant reduction effect was observed in the dichotic conditions. There was no distinct effect of the temporal characteristics of the stimuli on the amount of reduction. The attenuation was in 33% of the cases >3 dB for

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

    Science.gov (United States)

    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.

  3. Multiple time scales of adaptation in auditory cortex neurons.

    Science.gov (United States)

    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.

  4. Relations between perceptual measures of temporal processing, auditory-evoked brainstem responses and speech intelligibility in noise

    DEFF Research Database (Denmark)

    Papakonstantinou, Alexandra; Strelcyk, Olaf; Dau, Torsten

    2011-01-01

    This study investigates behavioural and objective measures of temporal auditory processing and their relation to the ability to understand speech in noise. The experiments were carried out on a homogeneous group of seven hearing-impaired listeners with normal sensitivity at low frequencies (up to 1...... kHz) and steeply sloping hearing losses above 1 kHz. For comparison, data were also collected for five normalhearing listeners. Temporal processing was addressed at low frequencies by means of psychoacoustical frequency discrimination, binaural masked detection and amplitude modulation (AM......) detection. In addition, auditory brainstem responses (ABRs) to clicks and broadband rising chirps were recorded. Furthermore, speech reception thresholds (SRTs) were determined for Danish sentences in speechshaped noise. The main findings were: (1) SRTs were neither correlated with hearing sensitivity...

  5. Elementary properties of Ca(2+) channels and their influence on multivesicular release and phase-locking at auditory hair cell ribbon synapses.

    Science.gov (United States)

    Magistretti, Jacopo; Spaiardi, Paolo; Johnson, Stuart L; Masetto, Sergio

    2015-01-01

    Voltage-gated calcium (Cav1.3) channels in mammalian inner hair cells (IHCs) open in response to sound and the resulting Ca(2+) entry triggers the release of the neurotransmitter glutamate onto afferent terminals. At low to mid sound frequencies cell depolarization follows the sound sinusoid and pulses of transmitter release from the hair cell generate excitatory postsynaptic currents (EPSCs) in the afferent fiber that translate into a phase-locked pattern of action potential activity. The present article summarizes our current understanding on the elementary properties of single IHC Ca(2+) channels, and how these could have functional implications for certain, poorly understood, features of synaptic transmission at auditory hair cell ribbon synapses.

  6. Elementary properties of Ca2+ channels and their influence on multivesicular release and phase-locking at auditory hair cell ribbon synapses

    Science.gov (United States)

    Magistretti, Jacopo; Spaiardi, Paolo; Johnson, Stuart L.; Masetto, Sergio

    2015-01-01

    Voltage-gated calcium (Cav1.3) channels in mammalian inner hair cells (IHCs) open in response to sound and the resulting Ca2+ entry triggers the release of the neurotransmitter glutamate onto afferent terminals. At low to mid sound frequencies cell depolarization follows the sound sinusoid and pulses of transmitter release from the hair cell generate excitatory postsynaptic currents (EPSCs) in the afferent fiber that translate into a phase-locked pattern of action potential activity. The present article summarizes our current understanding on the elementary properties of single IHC Ca2+ channels, and how these could have functional implications for certain, poorly understood, features of synaptic transmission at auditory hair cell ribbon synapses. PMID:25904847

  7. Modulation of Visually Evoked Postural Responses by Contextual Visual, Haptic and Auditory Information: A ‘Virtual Reality Check’

    Science.gov (United States)

    Meyer, Georg F.; Shao, Fei; White, Mark D.; Hopkins, Carl; Robotham, Antony J.

    2013-01-01

    Externally generated visual motion signals can cause the illusion of self-motion in space (vection) and corresponding visually evoked postural responses (VEPR). These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR) environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1) visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2) real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3) visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR. PMID:23840760

  8. Modulation of visually evoked postural responses by contextual visual, haptic and auditory information: a 'virtual reality check'.

    Directory of Open Access Journals (Sweden)

    Georg F Meyer

    Full Text Available Externally generated visual motion signals can cause the illusion of self-motion in space (vection and corresponding visually evoked postural responses (VEPR. These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1 visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2 real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3 visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR.

  9. Modulation of visually evoked postural responses by contextual visual, haptic and auditory information: a 'virtual reality check'.

    Science.gov (United States)

    Meyer, Georg F; Shao, Fei; White, Mark D; Hopkins, Carl; Robotham, Antony J

    2013-01-01

    Externally generated visual motion signals can cause the illusion of self-motion in space (vection) and corresponding visually evoked postural responses (VEPR). These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR) environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1) visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2) real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3) visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR.

  10. Music and natural sounds in an auditory steady-state response based brain-computer interface to increase user acceptance.

    Science.gov (United States)

    Heo, Jeong; Baek, Hyun Jae; Hong, Seunghyeok; Chang, Min Hye; Lee, Jeong Su; Park, Kwang Suk

    2017-05-01

    Patients with total locked-in syndrome are conscious; however, they cannot express themselves because most of their voluntary muscles are paralyzed, and many of these patients have lost their eyesight. To improve the quality of life of these patients, there is an increasing need for communication-supporting technologies that leverage the remaining senses of the patient along with physiological signals. The auditory steady-state response (ASSR) is an electro-physiologic response to auditory stimulation that is amplitude-modulated by a specific frequency. By leveraging the phenomenon whereby ASSR is modulated by mind concentration, a brain-computer interface paradigm was proposed to classify the selective attention of the patient. In this paper, we propose an auditory stimulation method to minimize auditory stress by replacing the monotone carrier with familiar music and natural sounds for an ergonomic system. Piano and violin instrumentals were employed in the music sessions; the sounds of water streaming and cicadas singing were used in the natural sound sessions. Six healthy subjects participated in the experiment. Electroencephalograms were recorded using four electrodes (Cz, Oz, T7 and T8). Seven sessions were performed using different stimuli. The spectral power at 38 and 42Hz and their ratio for each electrode were extracted as features. Linear discriminant analysis was utilized to classify the selections for each subject. In offline analysis, the average classification accuracies with a modulation index of 1.0 were 89.67% and 87.67% using music and natural sounds, respectively. In online experiments, the average classification accuracies were 88.3% and 80.0% using music and natural sounds, respectively. Using the proposed method, we obtained significantly higher user-acceptance scores, while maintaining a high average classification accuracy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Auditory brainstem evoked responses and temperature monitoring during pediatric cardiopulmonary bypass.

    Science.gov (United States)

    Rodriguez, R A; Edmonds, H L; Auden, S M; Austin, E H

    1999-09-01

    To examine the effects of temperature on auditory brainstem responses (ABRs) in infants during hypothermic cardiopulmonary bypass for total circulatory arrest (TCA). The relationship between ABRs (as a surrogate measure of core-brain temperature) and body temperature as measured at several temperature monitoring sites was determined. In a prospective, observational study, ABRs were recorded non-invasively at normothermia and at every 1 or 2 degrees C change in ear-canal temperature during cooling and rewarming in 15 infants (ages: 2 days to 14 months) that required TCA. The ABR latencies and amplitudes and the lowest temperatures at which an ABR was identified (the threshold) were measured during both cooling and rewarming. Temperatures from four standard temperature monitoring sites were simultaneously recorded. The latencies of ABRs increased and amplitudes decreased with cooling (P < 0.01), but rewarming reversed these effects. The ABR threshold temperature as related to each monitoring site (ear-canal, nasopharynx, esophagus and bladder) was respectively determined as 23 +/- 2.2 degrees C, 20.8 +/- 1.7 degrees C, 14.6 +/- 3.4 degrees C, and 21.5 +/- 3.8 degrees C during cooling and 21.8 +/- 1.6 degrees C, 22.4 +/- 2.0 degrees C, 27.6 +/- 3.6 degrees C, and 23.0 +/- 2.4 degrees C during rewarming. The rewarming latencies were shorter and Q10 latencies smaller than the corresponding cooling values (P < 0.01). Esophageal and bladder sites were more susceptible to temperature variations as compared with the ear-canal and nasopharynx. No temperature site reliably predicted an electrophysiological threshold. A faster latency recovery during rewarming suggests that body temperature monitoring underestimates the effects of rewarming in the core-brain. ABRs may be helpful to monitor the effects of cooling and rewarming on the core-brain during pediatric cardiopulmonary bypass.

  12. Attending to auditory memory.

    Science.gov (United States)

    Zimmermann, Jacqueline F; Moscovitch, Morris; Alain, Claude

    2016-06-01

    Attention to memory describes the process of attending to memory traces when the object is no longer present. It has been studied primarily for representations of visual stimuli with only few studies examining attention to sound object representations in short-term memory. Here, we review the interplay of attention and auditory memory with an emphasis on 1) attending to auditory memory in the absence of related external stimuli (i.e., reflective attention) and 2) effects of existing memory on guiding attention. Attention to auditory memory is discussed in the context of change deafness, and we argue that failures to detect changes in our auditory environments are most likely the result of a faulty comparison system of incoming and stored information. Also, objects are the primary building blocks of auditory attention, but attention can also be directed to individual features (e.g., pitch). We review short-term and long-term memory guided modulation of attention based on characteristic features, location, and/or semantic properties of auditory objects, and propose that auditory attention to memory pathways emerge after sensory memory. A neural model for auditory attention to memory is developed, which comprises two separate pathways in the parietal cortex, one involved in attention to higher-order features and the other involved in attention to sensory information. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    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

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

    NARCIS (Netherlands)

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

    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

  15. Searching for the optimal stimulus eliciting auditory brainstem responses in humans

    DEFF Research Database (Denmark)

    Fobel, Oliver; Dau, Torsten

    2004-01-01

    -chirp, was based on estimates of human basilar membrane (BM) group delays derived from stimulus-frequency otoacoustic emissions (SFOAE) at a sound pressure level of 40 dB [Shera and Guinan, in Recent Developments in Auditory Mechanics (2000)]. The other chirp, referred to as the A-chirp, was derived from latency...

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

    Science.gov (United States)

    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.

  17. Speech auditory brainstem response (speech ABR) characteristics depending on recording conditions, and hearing status: an experimental parametric study.

    Science.gov (United States)

    Akhoun, Idrick; Moulin, Annie; Jeanvoine, Arnaud; Ménard, Mikael; Buret, François; Vollaire, Christian; Scorretti, Riccardo; Veuillet, Evelyne; Berger-Vachon, Christian; Collet, Lionel; Thai-Van, Hung

    2008-11-15

    Speech elicited auditory brainstem responses (Speech ABR) have been shown to be an objective measurement of speech processing in the brainstem. Given the simultaneous stimulation and recording, and the similarities between the recording and the speech stimulus envelope, there is a great risk of artefactual recordings. This study sought to systematically investigate the source of artefactual contamination in Speech ABR response. In a first part, we measured the sound level thresholds over which artefactual responses were obtained, for different types of transducers and experimental setup parameters. A watermelon model was used to model the human head susceptibility to electromagnetic artefact. It was found that impedances between the electrodes had a great effect on electromagnetic susceptibility and that the most prominent artefact is due to the transducer's electromagnetic leakage. The only artefact-free condition was obtained with insert-earphones shielded in a Faraday cage linked to common ground. In a second part of the study, using the previously defined artefact-free condition, we recorded speech ABR in unilateral deaf subjects and bilateral normal hearing subjects. In an additional control condition, Speech ABR was recorded with the insert-earphones used to deliver the stimulation, unplugged from the ears, so that the subjects did not perceive the stimulus. No responses were obtained from the deaf ear of unilaterally hearing impaired subjects, nor in the insert-out-of-the-ear condition in all the subjects, showing that Speech ABR reflects the functioning of the auditory pathways.

  18. The effect of compression on tuning estimates in a simple nonlinear auditory filter model

    DEFF Research Database (Denmark)

    Marschall, Marton; MacDonald, Ewen; Dau, Torsten

    2013-01-01

    Behavioral experiments using auditory masking have been used to characterize frequency selectivity, one of the basic properties of the auditory system. However, due to the nonlinear response of the basilar membrane, the interpretation of these experiments may not be straightforward. Specifically,...

  19. Neonatal hearing screening of high-risk infants using automated auditory brainstem response: a retrospective analysis of referral rates.

    LENUS (Irish Health Repository)

    McGurgan, I J

    2013-10-07

    The past decade has seen the widespread introduction of universal neonatal hearing screening (UNHS) programmes worldwide. Regrettably, such a programme is only now in the process of nationwide implementation in the Republic of Ireland and has been largely restricted to one screening modality for initial testing; namely transient evoked otoacoustic emissions (TEOAE). The aim of this study is to analyse the effects of employing a different screening protocol which utilises an alternative initial test, automated auditory brainstem response (AABR), on referral rates to specialist audiology services.

  20. The amplitude and phase precision of 40 Hz auditory steady-state response depend on the level of arousal

    DEFF Research Database (Denmark)

    Griskova, Inga; Mørup, Morten; Parnas, Josef

    2007-01-01

    The aim of this study was to investigate, in healthy subjects, the modulation of amplitude and phase precision of the auditory steady-state response (ASSR) to 40 Hz stimulation in two resting conditions varying in the level of arousal. Previously, ASSR measures have shown to be affected......-negative multi-way factorization (NMWF) (Morup et al. in J Neurosci Methods 161:361-368, 2007). The estimates of these measures were subjected to statistical analysis. The amplitude and phase precision of the ASSR were significantly larger during the low arousal state compared to the high arousal condition...

  1. Knockdown of the dyslexia-associated gene Kiaa0319 impairs temporal responses to speech stimuli in rat primary auditory cortex.

    Science.gov (United States)

    Centanni, T M; Booker, A B; Sloan, A M; Chen, F; Maher, B J; Carraway, R S; Khodaparast, N; Rennaker, R; LoTurco, J J; Kilgard, M P

    2014-07-01

    One in 15 school age children have dyslexia, which is characterized by phoneme-processing problems and difficulty learning to read. Dyslexia is associated with mutations in the gene KIAA0319. It is not known whether reduced expression of KIAA0319 can degrade the brain's ability to process phonemes. In the current study, we used RNA interference (RNAi) to reduce expression of Kiaa0319 (the rat homolog of the human gene KIAA0319) and evaluate the effect in a rat model of phoneme discrimination. Speech discrimination thresholds in normal rats are nearly identical to human thresholds. We recorded multiunit neural responses to isolated speech sounds in primary auditory cortex (A1) of rats that received in utero RNAi of Kiaa0319. Reduced expression of Kiaa0319 increased the trial-by-trial variability of speech responses and reduced the neural discrimination ability of speech sounds. Intracellular recordings from affected neurons revealed that reduced expression of Kiaa0319 increased neural excitability and input resistance. These results provide the first evidence that decreased expression of the dyslexia-associated gene Kiaa0319 can alter cortical responses and impair phoneme processing in auditory cortex. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Responses of mink to auditory stimuli: Prerequisites for applying the ‘cognitive bias’ approach

    DEFF Research Database (Denmark)

    Svendsen, Pernille Maj; Malmkvist, Jens; Halekoh, Ulrich

    2012-01-01

    The aim of the study was to determine and validate prerequisites for applying a cognitive (judgement) bias approach to assessing welfare in farmed mink (Neovison vison). We investigated discrimination ability and associative learning ability using auditory cues. The mink (n = 15 females) were...... farmed mink in a judgement bias approach would thus appear to be feasible. However several specific issues are to be considered in order to successfully adapt a cognitive bias approach to mink, and these are discussed....

  3. Effects of an NMDA antagonist on the auditory mismatch negativity response to transcranial direct current stimulation.

    Science.gov (United States)

    Impey, Danielle; de la Salle, Sara; Baddeley, Ashley; Knott, Verner

    2017-05-01

    Transcranial direct current stimulation (tDCS) is a non-invasive form of brain stimulation which uses a weak constant current to alter cortical excitability and activity temporarily. tDCS-induced increases in neuronal excitability and performance improvements have been observed following anodal stimulation of brain regions associated with visual and motor functions, but relatively little research has been conducted with respect to auditory processing. Recently, pilot study results indicate that anodal tDCS can increase auditory deviance detection, whereas cathodal tDCS decreases auditory processing, as measured by a brain-based event-related potential (ERP), mismatch negativity (MMN). As evidence has shown that tDCS lasting effects may be dependent on N-methyl-D-aspartate (NMDA) receptor activity, the current study investigated the use of dextromethorphan (DMO), an NMDA antagonist, to assess possible modulation of tDCS's effects on both MMN and working memory performance. The study, conducted in 12 healthy volunteers, involved four laboratory test sessions within a randomised, placebo and sham-controlled crossover design that compared pre- and post-anodal tDCS over the auditory cortex (2 mA for 20 minutes to excite cortical activity temporarily and locally) and sham stimulation (i.e. device is turned off) during both DMO (50 mL) and placebo administration. Anodal tDCS increased MMN amplitudes with placebo administration. Significant increases were not seen with sham stimulation or with anodal stimulation during DMO administration. With sham stimulation (i.e. no stimulation), DMO decreased MMN amplitudes. Findings from this study contribute to the understanding of underlying neurobiological mechanisms mediating tDCS sensory and memory improvements.

  4. Are Auditory Steady-State Responses Useful to Evaluate Severe-to-Profound Hearing Loss in Children?

    Science.gov (United States)

    Grasel, Signe Schuster; de Almeida, Edigar Rezende; Beck, Roberto Miquelino de Oliveira; Goffi-Gomez, Maria Valéria Schmidt; Ramos, Henrique Faria; Rossi, Amanda Costa; Koji Tsuji, Robinson; Bento, Ricardo Ferreira; de Brito, Rubens

    2015-01-01

    To evaluate Auditory Steady-State Responses (ASSR) at high intensities in pediatric cochlear implant candidates and to compare the results to behavioral tests responses. This prospective study evaluated 42 children with suspected severe-to-profound hearing loss, aged from 3 to 72 months. All had absent ABR and OAE responses. ASSR were evoked using binaural single frequency stimuli at 110 dB HL with a 10 dB down-seeking procedure. ASSR and behavioral test results were compared. Forty-two subjects completed both ASSR and behavioral evaluation. Eleven children (26.2%) had bilateral responses. Four (9.5%) showed unilateral responses in at least two frequencies, all confirmed by behavioral results. Overall 61 ASSR responses were obtained, most (37.7%) in 500 Hz. Mean thresholds were between 101.3 and 104.2 dB HL. Among 27 subjects with absent ASSR, fifteen had no behavioral responses. Seven subjects showed behavioral responses with absent ASSR responses. No spurious ASSR responses were observed at 100 or 110 dB HL. ASSR is a valuable tool to detect residual hearing. No false-positive ASSR results were observed among 42 children, but in seven cases with absent ASSR, the test underestimated residual hearing as compared to the behavioral responses.

  5. Are Auditory Steady-State Responses Useful to Evaluate Severe-to-Profound Hearing Loss in Children?

    Directory of Open Access Journals (Sweden)

    Signe Schuster Grasel

    2015-01-01

    Full Text Available Objective. To evaluate Auditory Steady-State Responses (ASSR at high intensities in pediatric cochlear implant candidates and to compare the results to behavioral tests responses. Methods. This prospective study evaluated 42 children with suspected severe-to-profound hearing loss, aged from 3 to 72 months. All had absent ABR and OAE responses. ASSR were evoked using binaural single frequency stimuli at 110 dB HL with a 10 dB down-seeking procedure. ASSR and behavioral test results were compared. Results. Forty-two subjects completed both ASSR and behavioral evaluation. Eleven children (26.2% had bilateral responses. Four (9.5% showed unilateral responses in at least two frequencies, all confirmed by behavioral results. Overall 61 ASSR responses were obtained, most (37.7% in 500 Hz. Mean thresholds were between 101.3 and 104.2 dB HL. Among 27 subjects with absent ASSR, fifteen had no behavioral responses. Seven subjects showed behavioral responses with absent ASSR responses. No spurious ASSR responses were observed at 100 or 110 dB HL. Conclusion. ASSR is a valuable tool to detect residual hearing. No false-positive ASSR results were observed among 42 children, but in seven cases with absent ASSR, the test underestimated residual hearing as compared to the behavioral responses.

  6. Long-range correlation properties in timing of skilled piano performance: the influence of auditory feedback and deep brain stimulation.

    Directory of Open Access Journals (Sweden)

    Maria eHerrojo Ruiz

    2014-09-01

    Full Text Available Unintentional timing deviations during musical performance can be conceived of as timing errors. However, recent research on humanizing computer-generated music has demonstrated that timing fluctuations that exhibit long-range temporal correlations (LRTC are preferred by human listeners. This preference can be accounted for by the ubiquitous presence of LRTC in human tapping and rhythmic performances. Interestingly, the manifestation of LRTC in tapping behavior seems to be driven in a subject-specific manner by the LRTC properties of resting-state background cortical oscillatory activity. In this framework, the current study aimed to investigate whether propagation of timing deviations during the skilled, memorized piano performance (without metronome of 17 professional pianists exhibits LRTC and whether the structure of the correlations is influenced by the presence or absence of auditory feedback.As an additional goal, we set out to investigate the influence of altering the dynamics along the cortico-basal-ganglia-thalamo-cortical network via deep brain stimulation (DBS on the LRTC properties of musical performance. Specifically, we investigated temporal deviations during the skilled piano performance of a non-professional pianist who was treated with subthalamic-deep brain stimulation (STN-DBS due to severe Parkinson's disease, with predominant tremor affecting his right upper extremity. In the tremor-affected right hand, the timing fluctuations of the performance exhibited random correlations with DBS OFF. By contrast, DBS restored long-range dependency in the temporal fluctuations, corresponding with the general motor improvement on DBS.Overall, the present investigations are the first to demonstrate the presence of LRTC in skilled piano performances, indicating that unintentional temporal deviations are correlated over a wide range of time scales. This phenomenon is stable after removal of the auditory feedback, but is altered by STN

  7. Cerebral Responses to Vocal Attractiveness and Auditory Hallucinations in Schizophrenia: A Functional MRI Study

    Directory of Open Access Journals (Sweden)

    Michihiko eKoeda

    2013-05-01

    Full Text Available Impaired self-monitoring and abnormalities of cognitive bias have been implicated as cognitive mechanisms of hallucination; regions fundamental to these processes including inferior frontal gyrus (IFG and superior temporal gyrus (STG are abnormally activated in individuals that hallucinate. A recent study showed activation in IFG-STG to be modulated by auditory attractiveness, but no study has investigated whether these IFG-STG activations are impaired in schizophrenia. We aimed to clarify the cerebral function underlying the perception of auditory attractiveness in schizophrenia patients. Cerebral activation was examined in 18 schizophrenia patients and 18 controls when performing Favourability Judgment Task (FJT and Gender Differentiation Task (GDT for pairs of greetings using event-related functional MRI. A full-factorial analysis revealed that the main effect of task was associated with activation of left IFG and STG. The main effect of Group revealed less activation of left STG in schizophrenia compared with controls, whereas significantly greater activation in schizophrenia than in controls was revealed at the left middle frontal gyrus (MFG, right temporo-parietal junction (TPJ, right occipital lobe, and right amygdala (p<0.05, FDR-corrected. A significant positive correlation was observed at the right TPJ and right MFG between cerebral activation under FJT minus GDT contrast and the score of hallucinatory behaviour on the Positive and Negative Symptom Scale. Findings of hypo-activation in the left STG could designate brain dysfunction in accessing vocal attractiveness in schizophrenia, whereas hyper-activation in the right TPJ and MFG may reflect the process of mentalizing other person’s behaviour by auditory hallucination by abnormality of cognitive bias.

  8. Auditory middle latency responses differ in right- and left-handed subjects: an evaluation through topographic brain mapping.

    Science.gov (United States)

    Mohebbi, Mehrnaz; Mahmoudian, Saeid; Alborzi, Marzieh Sharifian; Najafi-Koopaie, Mojtaba; Farahani, Ehsan Darestani; Farhadi, Mohammad

    2014-09-01

    To investigate the association of handedness with auditory middle latency responses (AMLRs) using topographic brain mapping by comparing amplitudes and latencies in frontocentral and hemispheric regions of interest (ROIs). The study included 44 healthy subjects with normal hearing (22 left handed and 22 right handed). AMLRs were recorded from 29 scalp electrodes in response to binaural 4-kHz tone bursts. Frontocentral ROI comparisons revealed that Pa and Pb amplitudes were significantly larger in the left-handed than the right-handed group. Topographic brain maps showed different distributions in AMLR components between the two groups. In hemispheric comparisons, Pa amplitude differed significantly across groups. A left-hemisphere emphasis of Pa was found in the right-handed group but not in the left-handed group. This study provides evidence that handedness is associated with AMLR components in frontocentral and hemispheric ROI. Handedness should be considered an essential factor in the clinical or experimental use of AMLRs.

  9. Auditory agnosia.

    Science.gov (United States)

    Slevc, L Robert; Shell, Alison R

    2015-01-01

    Auditory agnosia refers to impairments in sound perception and identification despite intact hearing, cognitive functioning, and language abilities (reading, writing, and speaking). Auditory agnosia can be general, affecting all types of sound perception, or can be (relatively) specific to a particular domain. Verbal auditory agnosia (also known as (pure) word deafness) refers to deficits specific to speech processing, environmental sound agnosia refers to difficulties confined to non-speech environmental sounds, and amusia refers to deficits confined to music. These deficits can be apperceptive, affecting basic perceptual processes, or associative, affecting the relation of a perceived auditory object to its meaning. This chapter discusses what is known about the behavioral symptoms and lesion correlates of these different types of auditory agnosia (focusing especially on verbal auditory agnosia), evidence for the role of a rapid temporal processing deficit in some aspects of auditory agnosia, and the few attempts to treat the perceptual deficits associated with auditory agnosia. A clear picture of auditory agnosia has been slow to emerge, hampered by the considerable heterogeneity in behavioral deficits, associated brain damage, and variable assessments across cases. Despite this lack of clarity, these striking deficits in complex sound processing continue to inform our understanding of auditory perception and cognition. © 2015 Elsevier B.V. All rights reserved.

  10. Musical Auditory Stimulation Influences Heart Rate Autonomic Responses to Endodontic Treatment

    Directory of Open Access Journals (Sweden)

    Milana Drumond Ramos Santana

    2017-01-01

    Full Text Available We aimed to evaluate the acute effect of musical auditory stimulation on heart rate autonomic regulation during endodontic treatment. The study included 50 subjects from either gender between 18 and 40 years old, diagnosed with irreversible pulpitis or pulp necrosis of the upper front teeth and endodontic treatment indication. HRV was recorded 10 minutes before (T1, during (T2, and immediately (T3 and T4 after endodontic treatment. The volunteers were randomly divided into two equal groups: exposed to music (during T2, T3, and T4 or not. We found no difference regarding salivary cortisol and anxiety score. In the group with musical stimulation heart rate decreased in T3 compared to T1 and mean RR interval increased in T2 and T3 compared to T1. SDNN and TINN indices decreased in T3 compared to T4, the RMSSD and SD1 increased in T4 compared to T1, the SD2 increased compared to T3, and LF (low frequency band increased in T4 compared to T1 and T3. In the control group, only RMSSD and SD1 increased in T3 compared to T1. Musical auditory stimulation enhanced heart rate autonomic modulation during endodontic treatment.

  11. Maturation of the auditory t-complex brain response across adolescence.

    Science.gov (United States)

    Mahajan, Yatin; McArthur, Genevieve

    2013-02-01

    Adolescence is a time of great change in the brain in terms of structure and function. It is possible to track the development of neural function across adolescence using auditory event-related potentials (ERPs). This study tested if the brain's functional processing of sound changed across adolescence. We measured passive auditory t-complex peaks to pure tones and consonant-vowel (CV) syllables in 90 children and adolescents aged 10-18 years, as well as 10 adults. Across adolescence, Na amplitude increased to tones and speech at the right, but not left, temporal site. Ta amplitude decreased at the right temporal site for tones, and at both sites for speech. The Tb remained constant at both sites. The Na and Ta appeared to mature later in the right than left hemisphere. The t-complex peaks Na and Tb exhibited left lateralization and Ta showed right lateralization. Thus, the functional processing of sound continued to develop across adolescence and into adulthood. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  12. Hypnotizability and Placebo Analgesia in Waking and Hypnosis as Modulators of Auditory Startle Responses in Healthy Women: An ERP Study.

    Science.gov (United States)

    De Pascalis, Vilfredo; Scacchia, Paolo

    2016-01-01

    We evaluated the influence of hypnotizability, pain expectation, placebo analgesia in waking and hypnosis on tonic pain relief. We also investigated how placebo analgesia affects somatic responses (eye blink) and N100 and P200 waves of event-related potentials (ERPs) elicited by auditory startle probes. Although expectation plays an important role in placebo and hypnotic analgesia, the neural mechanisms underlying these treatments are still poorly understood. We used the cold cup test (CCT) to induce tonic pain in 53 healthy women. Placebo analgesia was initially produced by manipulation, in which the intensity of pain induced by the CCT was surreptitiously reduced after the administration of a sham analgesic cream. Participants were then tested in waking and hypnosis under three treatments: (1) resting (Baseline); (2) CCT-alone (Pain); and (3) CCT plus placebo cream for pain relief (Placebo). For each painful treatment, we assessed pain and distress ratings, eye blink responses, N100 and P200 amplitudes. We used LORETA analysis of N100 and P200 waves, as elicited by auditory startle, to identify cortical regions sensitive to pain reduction through placebo and hypnotic analgesia. Higher pain expectation was associated with higher pain reductions. In highly hypnotizable participants placebo treatment produced significant reductions of pain and distress perception in both waking and hypnosis condition. P200 wave, during placebo analgesia, was larger in the frontal left hemisphere while placebo analgesia, during hypnosis, involved the activity of the left hemisphere including the occipital region. These findings demonstrate that hypnosis and placebo analgesia are different processes of top-down regulation. Pain reduction was associated with larger EMG startle amplitudes, N100 and P200 responses, and enhanced activity within the frontal, parietal, and anterior and posterior cingulate gyres. LORETA results showed that placebo analgesia modulated pain-responsive areas

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Music and the auditory brain: where is the connection?

    Directory of Open Access Journals (Sweden)

    Israel eNelken

    2011-09-01

    Full Text Available Sound processing by the auditory system is understood in unprecedented details, even compared with sensory coding in the visual system. Nevertheless, we don't understand yet the way in which some of the simplest perceptual properties of sounds are coded in neuronal activity. This poses serious difficulties for linking neuronal responses in the auditory system and music processing, since music operates on abstract representations of sounds. Paradoxically, although perceptual representations of sounds most probably occur high in auditory system or even beyond it, neuronal responses are strongly affected by the temporal organization of sound streams even in subcortical stations. Thus, to the extent that music is organized sound, it is the organization, rather than the sound, which is represented first in the auditory brain.

  15. Estimation of Human Workload from the Auditory Steady-State Response Recorded via a Wearable Electroencephalography System during Walking

    Directory of Open Access Journals (Sweden)

    Yusuke Yokota

    2017-06-01

    Full Text Available Workload in the human brain can be a useful marker of internal brain state. However, due to technical limitations, previous workload studies have been unable to record brain activity via conventional electroencephalography (EEG and magnetoencephalography (MEG devices in mobile participants. In this study, we used a wearable EEG system to estimate workload while participants walked in a naturalistic environment. Specifically, we used the auditory steady-state response (ASSR which is an oscillatory brain activity evoked by repetitive auditory stimuli, as an estimation index of workload. Participants performed three types of N-back tasks, which were expected to command different workloads, while walking at a constant speed. We used a binaural 500 Hz pure tone with amplitude modulation at 40 Hz to evoke the ASSR. We found that the phase-locking index (PLI of ASSR activity was significantly correlated with the degree of task difficulty, even for EEG data from few electrodes. Thus, ASSR appears to be an effective indicator of workload during walking in an ecologically valid environment.

  16. Brainstem auditory evoked response characteristics in normal-hearing subjects with chronic tinnitus and in non-tinnitus group

    Directory of Open Access Journals (Sweden)

    Shadman Nemati

    2014-06-01

    Full Text Available Background and Aim: While most of the people with tinnitus have some degrees of hearing impairment, a small percent of patients admitted to ear, nose and throat clinics or hearing evaluation centers are those who complain of tinnitus despite having normal hearing thresholds. This study was performed to better understanding of the reasons of probable causes of tinnitus and to investigate possible changes in the auditory brainstem function in normal-hearing patients with chronic tinnitus.Methods: In this comparative cross-sectional, descriptive and analytic study, 52 ears (26 with and 26 without tinnitus were examined. Components of the auditory brainstem response (ABR including wave latencies and wave amplitudes were determined in the two groups and analyzed using appropriate statistical methods.Results: The mean differences between the absolute latencies of waves I, III and V was less than 0.1 ms between the two groups that was not statistically significant. Also, the interpeak latency values of waves I-III, III-V and I-V in both groups had no significant difference. Only, the V/I amplitude ratio in the tinnitus group was significantly higher (p=0.04.Conclusion: The changes observed in amplitude of waves, especially in the latter ones, can be considered as an indication of plastic changes in neuronal activity and its possible role in generation of tinnitus in normal-hearing patients.

  17. Oral Contraceptives Attenuate Cardiac Autonomic Responses to Musical Auditory Stimulation: Pilot Study.

    Science.gov (United States)

    Milan, Réveni Carmem; Plassa, Bruna Oliveira; Guida, Heraldo Lorena; de Abreu, Luiz Carlos; Gomes, Rayana L; Garner, David M; Valenti, Vitor E

    2015-01-01

    The literature presents contradictory results regarding the effects of contraceptives on cardiac autonomic regulation. The research team aimed to evaluate the effects of musical auditory stimulation on cardiac autonomic regulation in women who use oral contraceptives. The research team designed a transversal observational pilot study. The setting was the Centro de Estudos do Sistema Nervoso Autônomo (CESNA) in the Departamento de Fonoaudiologia at the Universidade Estadual Paulista (UNESP) in Marília, SP, Brazil. Participants were 22 healthy nonathletic and nonsedentary females, all nonsmokers and aged between 18 and 27 y. Participants were divided into 2 groups: (1) 12 women who were not taking oral contraceptives, the control group; and (2) 10 women who were taking oral contraceptives, the oral contraceptive group. In the first stage, a rest control, the women sat with their earphones turned off for 20 min. After that period, the participants were exposed to 20 min of classical baroque music (ie, "Canon in D Major," Johann Pachelbel), at 63-84 dB. Measurements of the equivalent sound levels were conducted in a soundproof room, and the intervals between consecutive heartbeats (R-R intervals) were recorded, with a sampling rate of 1000 Hz. For calculation of the linear indices, the research team used software to perform an analysis of heart rate variability (HRV). Linear indices of HRV were analyzed in the time domain: (1) the standard deviation of normal-to-normal R-R intervals (SDNN), (2) the root-mean square of differences between adjacent normal R-R intervals in a time interval (RMSSD), and (3) the percentage of adjacent R-R intervals with a difference of duration greater than 50 ms (pNN50). The study also analyzed the frequency domain-low frequency (LF), high frequency (HF), and LF/HF ratio. For the control group, the musical auditory stimulation reduced (1) the SDNN from 52.2 ± 10 ms to 48.4 ± 16 ms (P = .0034); (2) the RMSSD from 45.8 ± 22 ms to 41.2

  18. Effects of glutamate receptor agonists on the P13 auditory evoked potential and startle response in the rat

    Directory of Open Access Journals (Sweden)

    Christen eSimon

    2011-01-01

    Full Text Available The P13 potential is the rodent equivalent of the P50 potential, which is an evoked response recorded at the vertex (Vx 50 msec following an auditory stimulus in humans. Both the P13 and P50 potentials are only present during waking and rapid eye movement (REM sleep, and are considered to be measures of level of arousal. The source of the P13 and P50 potentials appears to be the pedunculopontine nucleus (PPN, a brainstem nucleus with indirect ascending projections to the cortex through the intralaminar thalamus (ILT, mediating arousal, and descending inhibitory projections to the caudal pontine reticular formation (CPRF, which mediates the auditory startle response (SR. We tested the hypothesis that intracranial microinjection (ICM of glutamate (GLU or GLU receptor agonists will increase the activity of PPN neurons, resulting in an increased P13 potential response, and decreased SR due to inhibitory projections from the PPN to the CPRF, in freely moving animals. Cannulae were inserted into the PPN to inject neuroactive agents, screws were inserted into the Vx in order to record the P13 potential, and electrodes inserted into the dorsal nuchal muscle to record electromyograms (EMGs and SR amplitude. Our results showed that ICM of GLU into the PPN dose-dependently increased the amplitude of the P13 potential and decreased the amplitude of the SR. Similarly, ICM of NMDA or KA into the PPN increased the amplitude of the P13 potential. These findings indicate that glutamatergic input to the PPN plays a role in arousal control in vivo, and changes in glutamatergic input, or excitability of PPN neurons, could be implicated in a number of neuropsychiatric disorders with the common symptoms of hyperarousal and REM sleep dysregulation.

  19. Pleasurable emotional response to music: a case of neurodegenerative generalized auditory agnosia.

    Science.gov (United States)

    Matthews, Brandy R; Chang, Chiung-Chih; De May, Mary; Engstrom, John; Miller, Bruce L

    2009-06-01

    Recent functional neuroimaging studies implicate the network of mesolimbic structures known to be active in reward processing as the neural substrate of pleasure associated with listening to music. Psychoacoustic and lesion studies suggest that there is a widely distributed cortical network involved in processing discreet musical variables. Here we present the case of a young man with auditory agnosia as the consequence of cortical neurodegeneration who continues to experience pleasure when exposed to music. In a series of musical tasks, the subject was unable to accurately identify any of the perceptual components of music beyond simple pitch discrimination, including musical variables known to impact the perception of affect. The subject subsequently misidentified the musical character of personally familiar tunes presented experimentally, but continued to report that the activity of 'listening' to specific musical genres was an emotionally rewarding experience. The implications of this case for the evolving understanding of music perception, music misperception, music memory, and music-associated emotion are discussed.

  20. A Qualitative Analysis of Student Pharmacists’ Response after an Auditory Hallucination Simulation

    Directory of Open Access Journals (Sweden)

    Genevieve L Ness

    2017-08-01

    Full Text Available Objectives: The goal of this research was to evaluate pharmacy students’ experiences and reactions when exposed to an auditory hallucination simulator. Methods: A convenient sample of 16 pharmacy students enrolled in the Advanced Psychiatry Elective at a private, faith-based university in the southeastern United States was selected. Students participated in an activity in which they listened to an auditory hallucination simulator from their personal laptop computers and completed a variety of tasks. Following the conclusion of the simulator, students composed a reflection guided by a five-question prompt. Qualitative analysis of the reflections was then completed to identify and categorize overarching themes. Results: The overarching themes identified included: 1 students mentioned strategies they used to overcome the distraction; 2 students discussed how the voices affected their ability to complete the activities; 3 students discussed the mental/physical toll they experienced; 4 students identified methods to assist patients with schizophrenia; 5 students mentioned an increase in their empathy for patients; 6 students reported their reactions to the voices; 7 students recognized how schizophrenia could affect the lives of these patients; and 8 students expressed how their initial expectations and reactions to the voices changed throughout the course of the simulation. Overall, the use of this simulator as a teaching aid was well received by students. Summary: In conclusion, pharmacy students were impacted by the hallucination simulator and expressed an increased awareness of the challenges faced by these patients on a daily basis. Conflict of Interest We declare no conflicts of interest or financial interests that the authors or members of their immediate families have in any product or service discussed in the manuscript, including grants (pending or received, employment, gifts, stock holdings or options, honoraria, consultancies, expert

  1. 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

  2. Abnormal auditory mismatch response in tinnitus sufferers with high-frequency hearing loss is associated with subjective distress level

    Directory of Open Access Journals (Sweden)

    Berg Patrick

    2004-03-01

    Full Text Available Abstract Background Tinnitus is an auditory sensation frequently following hearing loss. After cochlear injury, deafferented neurons become sensitive to neighbouring intact edge-frequencies, guiding an enhanced central representation of these frequencies. As psychoacoustical data 123 indicate enhanced frequency discrimination ability for edge-frequencies that may be related to a reorganization within the auditory cortex, the aim of the present study was twofold: 1 to search for abnormal auditory mismatch responses in tinnitus sufferers and 2 relate these to subjective indicators of tinnitus. Results Using EEG-mismatch negativity, we demonstrate abnormalities (N = 15 in tinnitus sufferers that are specific to frequencies located at the audiometrically normal lesion-edge as compared to normal hearing controls (N = 15. Groups also differed with respect to the cortical locations of mismatch responsiveness. Sources in the 90–135 ms latency window were generated in more anterior brain regions in the tinnitus group. Both measures of abnormality correlated with emotional-cognitive distress related to tinnitus (r ~ .76. While these two physiological variables were uncorrelated in the control group, they were correlated in the tinnitus group (r = .72. Concerning relationships with parameters of hearing loss (depth and slope, slope turned out to be an important variable. Generally, the steeper the hearing loss is the less distress related to tinnitus was reported. The associations between slope and the relevant neurophysiological variables are in agreement with this finding. Conclusions The present study is the first to show near-to-complete separation of tinnitus sufferers from a normal hearing control group based on neurophysiological variables. The finding of lesion-edge specific effects and associations with slope of hearing loss corroborates the assumption that hearing loss is the basis for tinnitus development. It is likely that some central

  3. 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...

  4. Directionality of auditory nerve fiber responses to pure tone stimuli in the grassfrog, Rana temporaria. II. Spike timing

    DEFF Research Database (Denmark)

    Jørgensen, M B; Christensen-Dalsgaard, J

    1997-01-01

    We studied the directionality of spike timing in the responses of single auditory nerve fibers of the grass frog, Rana temporaria, to tone burst stimulation. Both the latency of the first spike after stimulus onset and the preferred firing phase during the stimulus were studied. In addition, the ...

  5. Auditory sensory processing deficits in sensory gating and mismatch negativity-like responses in the social isolation rat model of schizophrenia

    DEFF Research Database (Denmark)

    Witten, Louise; Oranje, Bob; Mørk, Arne

    2014-01-01

    Patients with schizophrenia exhibit disturbances in information processing. These disturbances can be investigated with different paradigms of auditory event related potentials (ERP), such as sensory gating in a double click paradigm (P50 suppression) and the mismatch negativity (MMN) component...... in an auditory oddball paradigm. The aim of the current study was to test if rats subjected to social isolation, which is believed to induce some changes that mimic features of schizophrenia, displays alterations in sensory gating and MMN-like response. Male Lister-Hooded rats were separated into two groups; one...... group socially isolated (SI) for 8 weeks and one group housed (GH). Both groups were then tested in a double click sensory gating paradigm and an auditory oddball paradigm (MMN-like) paradigm. It was observed that the SI animals showed reduced sensory gating of the cortical N1 amplitude. Furthermore...

  6. Auditory Spatial Layout

    Science.gov (United States)

    Wightman, Frederic L.; Jenison, Rick

    1995-01-01

    All auditory sensory information is packaged in a pair of acoustical pressure waveforms, one at each ear. While there is obvious structure in these waveforms, that structure (temporal and spectral patterns) bears no simple relationship to the structure of the environmental objects that produced them. The properties of auditory objects and their layout in space must be derived completely from higher level processing of the peripheral input. This chapter begins with a discussion of the peculiarities of acoustical stimuli and how they are received by the human auditory system. A distinction is made between the ambient sound field and the effective stimulus to differentiate the perceptual distinctions among various simple classes of sound sources (ambient field) from the known perceptual consequences of the linear transformations of the sound wave from source to receiver (effective stimulus). Next, the definition of an auditory object is dealt with, specifically the question of how the various components of a sound stream become segregated into distinct auditory objects. The remainder of the chapter focuses on issues related to the spatial layout of auditory objects, both stationary and moving.

  7. 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

  8. Animal models for auditory streaming

    Science.gov (United States)

    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

  9. Investigation of Auditory Brain Stem Responses (ABRs In Children with Down Syndrome

    Directory of Open Access Journals (Sweden)

    Mohsen Monadi

    2013-04-01

    Full Text Available Objective: The aim of this study was comparing ABR in normal and down children. Materials & Methods: This study was performed between 1388 to 1391 at Akhavan rehabilitation center of University of Social Welfare and Rehabilitation Sciences Tehran and Babol Amir Kola hospital. Forty five 3-6 year-old boy with Down’s syndrome and forty five normal children were selected from available population. After case history, otoscopy and basic hearing tests, ABR test was performed. In ABR absolute latencies, interpeak latencies and amplitude ratio of V/I were analyzed. For analyzing data, parametric independent t test was selected. Results: Latencies and inter-peak latencies of I-III, I-V (P-value<0.001, III-V (P-value=0.01 and V/I amplitude ratio (P-value<0.001 were shorter than normal. Children with Down syndrome had significantly higher threshold than normal children (P-value<0.001. Conclusion: Peripheral auditory system development is delayed and brainstem function in children with Down’s syndrome is abnormal. Early diagnosis of hearing impairments and intervention in these children is very important because it affects communication skills.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  12. AUDITORY NUCLEI: DISTINCTIVE RESPONSE PATTERNS TO WHITE NOISE AND TONES IN UNANESTHETIZED CATS.

    Science.gov (United States)

    GALIN, D

    1964-10-09

    Electrical responses to "white" noise and tonal stimuli were recorded from unanesthetized cats with permanently implanted bipolar electrodes. The cochlear nucleus, inferior colliculus, and medial geniculate each showed distinctive patterns of evoked activity. White noise and tones produced qualitatively different types of response. A decrease in activity characterized the response of the inferior colliculus to tonal stimuli.

  13. Auditory Neuropathy

    Science.gov (United States)

    ... children and adults with auditory neuropathy. Cochlear implants (electronic devices that compensate for damaged or nonworking parts ... and Drug Administration: Information on Cochlear Implants Telecommunications Relay Services Your Baby's Hearing Screening News Deaf health ...

  14. Neural Correlates of Auditory Processing, Learning and Memory Formation in Songbirds

    Science.gov (United States)

    Pinaud, R.; Terleph, T. A.; Wynne, R. D.; Tremere, L. A.

    Songbirds have emerged as powerful experimental models for the study of auditory processing of complex natural communication signals. Intact hearing is necessary for several behaviors in developing and adult animals including vocal learning, territorial defense, mate selection and individual recognition. These behaviors are thought to require the processing, discrimination and memorization of songs. Although much is known about the brain circuits that participate in sensorimotor (auditory-vocal) integration, especially the ``song-control" system, less is known about the anatomical and functional organization of central auditory pathways. Here we discuss findings associated with a telencephalic auditory area known as the caudomedial nidopallium (NCM). NCM has attracted significant interest as it exhibits functional properties that may support higher order auditory functions such as stimulus discrimination and the formation of auditory memories. NCM neurons are vigorously dr iven by auditory stimuli. Interestingly, these responses are selective to conspecific, relative to heterospecific songs and artificial stimuli. In addition, forms of experience-dependent plasticity occur in NCM and are song-specific. Finally, recent experiments employing high-throughput quantitative proteomics suggest that complex protein regulatory pathways are engaged in NCM as a result of auditory experience. These molecular cascades are likely central to experience-associated plasticity of NCM circuitry and may be part of a network of calcium-driven molecular events that support the formation of auditory memory traces.

  15. Lateralization and Binaural Interaction of Middle-Latency and Late-Brainstem Components of the Auditory Evoked Response.

    Science.gov (United States)

    Dykstra, Andrew R; Burchard, Daniel; Starzynski, Christian; Riedel, Helmut; Rupp, Andre; Gutschalk, Alexander

    2016-08-01

    We used magnetoencephalography to examine lateralization and binaural interaction of the middle-latency and late-brainstem components of the auditory evoked response (the MLR and SN10, respectively). Click stimuli were presented either monaurally, or binaurally with left- or right-leading interaural time differences (ITDs). While early MLR components, including the N19 and P30, were larger for monaural stimuli presented contralaterally (by approximately 30 and 36 % in the left and right hemispheres, respectively), later components, including the N40 and P50, were larger ipsilaterally. In contrast, MLRs elicited by binaural clicks with left- or right-leading ITDs did not differ. Depending on filter settings, weak binaural interaction could be observed as early as the P13 but was clearly much larger for later components, beginning at the P30, indicating some degree of binaural linearity up to early stages of cortical processing. The SN10, an obscure late-brainstem component, was observed consistently in individuals and showed linear binaural additivity. The results indicate that while the MLR is lateralized in response to monaural stimuli-and not ITDs-this lateralization reverses from primarily contralateral to primarily ipsilateral as early as 40 ms post stimulus and is never as large as that seen with fMRI.

  16. Spectro-temporal characterization of auditory neurons: redundant or necessary?

    NARCIS (Netherlands)

    Eggermont, J.J.; Aertsen, A.M.H.J.; Hermes, D.J.; Johannesma, P.I.M.

    1981-01-01

    For neurons in the auditory midbrain of the grass frog the use of a combined spectro-temporal characterization has been evaluated against the separate characterizations of frequency-sensitivity and temporal response properties. By factoring the joint density function of stimulus intensity, I(f, t),

  17. The influence of cochlear traveling wave and neural adaptation on auditory brainstem responses

    DEFF Research Database (Denmark)

    Junius, D.; Dau, Torsten

    2005-01-01

    of the responses to the single components, as a function of stimulus level. In the first experiment, a single rising chirp was temporally and spectrally embedded in two steady-state tones. In the second experiment, the stimulus consisted of a continuous alternating train of chirps: each rising chirp was followed...... by the temporally reversed (falling) chirp. In both experiments, the transitions between stimulus components were continuous. For stimulation levels up to approximately 70 dB SPL, the responses to the embedded chirp corresponded to the responses to the single chirp. At high stimulus levels (80-100 dB SPL......), disparities occurred between the responses, reflecting a nonlinearity in the processing when neural activity is integrated across frequency. In the third experiment, the effect of within-train rate on wave-V response was investigated. The response to the chirp presented at a within-train rate of 95 Hz...

  18. Auditory hallucinations.

    Science.gov (United States)

    Blom, Jan Dirk

    2015-01-01

    Auditory hallucinations constitute a phenomenologically rich group of endogenously mediated percepts which are associated with psychiatric, neurologic, otologic, and other medical conditions, but which are also experienced by 10-15% of all healthy individuals in the general population. The group of phenomena is probably best known for its verbal auditory subtype, but it also includes musical hallucinations, echo of reading, exploding-head syndrome, and many other types. The subgroup of verbal auditory hallucinations has been studied extensively with the aid of neuroimaging techniques, and from those studies emerges an outline of a functional as well as a structural network of widely distributed brain areas involved in their mediation. The present chapter provides an overview of the various types of auditory hallucination described in the literature, summarizes our current knowledge of the auditory networks involved in their mediation, and draws on ideas from the philosophy of science and network science to reconceptualize the auditory hallucinatory experience, and point out directions for future research into its neurobiologic substrates. In addition, it provides an overview of known associations with various clinical conditions and of the existing evidence for pharmacologic and non-pharmacologic treatments. © 2015 Elsevier B.V. All rights reserved.

  19. Extra-auditory responses to long-term intermittent noise stimulation in humans.

    Science.gov (United States)

    Fruhstorfer, B; Hensel, H

    1980-12-01

    Respiration, heart rate, cutaneous blood flow, and electroencephalogram (EEG) reactions to long-term intermittent noise exposure were recorded from 13 volunteers (20-29 yr) with normal hearing and vegetative reactivity. They received daily within 1 h 12 noise stimuli (16 s 100 dB (A) white noise) for 10 or 21 days, respectively. Most subjects reported partial subjective adaptation to the noise. Heart rate adapted within a session but did not change considerably during successive days. Vascular responses did not change during one session but diminished mainly during the first 10 days. Noise responses in the EEG remained constant, but a decrease in vigilance occurred during the whole experimental series. Respiration responses were unpredictable and showed no trend within the sessions. It was concluded that certain physiological responses adapt to loud noise but that the time course of adaptation is different. Therefore a general statement about physiological noise adaptation is not possible.

  20. Differential modulation of auditory responses to attended and unattended speech in different listening conditions.

    Science.gov (United States)

    Kong, Ying-Yee; Mullangi, Ala; Ding, Nai

    2014-10-01

    This study investigates how top-down attention modulates neural tracking of the speech envelope in different listening conditions. In the quiet conditions, a single speech stream was presented and the subjects paid attention to the speech stream (active listening) or watched a silent movie instead (passive listening). In the competing speaker (CS) conditions, two speakers of opposite genders were presented diotically. Ongoing electroencephalographic (EEG) responses were measured in each condition and cross-correlated with the speech envelope of each speaker at different time lags. In quiet, active and passive listening resulted in similar neural responses to the speech envelope. In the CS conditions, however, the shape of the cross-correlation function was remarkably different between the attended and unattended speech. The cross-correlation with the attended speech showed stronger N1 and P2 responses but a weaker P1 response compared to the cross-correlation with the unattended speech. Furthermore, the N1 response to the attended speech in the CS condition was enhanced and delayed compared with the active listening condition in quiet, while the P2 response to the unattended speaker in the CS condition was attenuated compared with the passive listening in quiet. Taken together, these results demonstrate that top-down attention differentially modulates envelope-tracking neural activity at different time lags and suggest that top-down attention can both enhance the neural responses to the attended sound stream and suppress the responses to the unattended sound stream. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Auditory brainstem responses of CBA/J mice with neonatal conductive hearing losses and treatment with GM1 ganglioside.

    Science.gov (United States)

    Money, M K; Pippin, G W; Weaver, K E; Kirsch, J P; Webster, D B

    1995-07-01

    Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.

  2. Effects of noise exposure on neonatal auditory brainstem response thresholds in pregnant guinea pigs at different gestational periods.

    Science.gov (United States)

    Morimoto, Chihiro; Nario, Kazuhiko; Nishimura, Tadashi; Shimokura, Ryota; Hosoi, Hiroshi; Kitahara, Tadashi

    2017-01-01

    Noise exposure during pregnancy has been reported to cause fetal hearing impairment. However, little is known about the effects of noise exposure during various gestational stages on postnatal hearing. In the present study, we investigated the effects of noise exposure on auditory brainstem response (ABR) at the early, mid-, and late gestational periods in newborn guinea pigs. Pregnant guinea pigs were exposed to 4-kHz pure tone at a 120-dB sound pressure level for 4 h. We divided the animals into four groups as follows: the control, early gestational exposure, mid-gestational exposure, and late gestational exposure groups. ABR thresholds and latencies in newborns were recorded using 1-, 2-, and 4-kHz tone burst on postnatal days 1, 7, 14, and 28. Changes in ABR thresholds and latencies were measured between the 4 × 4 and 4 × 3 factorial groups mentioned above (gestational periods × postnatal days, gestational periods × frequencies). The thresholds were low in the order of control group guinea pigs. This is the first study to show that noise exposure during the early, mid-, and late gestational periods significantly elevated ABR thresholds in neonatal guinea pigs. © 2016 Japan Society of Obstetrics and Gynecology.

  3. The effects of aging on postural control and selective attention when stepping down while performing a concurrent auditory response task.

    Science.gov (United States)

    Tsang, William W N; Lam, Nazca K Y; Lau, Kit N L; Leung, Harry C H; Tsang, Crystal M S; Lu, Xi

    2013-12-01

    To investigate the effects of aging on postural control and cognitive performance in single- and dual-tasking. A cross-sectional comparative design was conducted in a university motion analysis laboratory. Young adults (n = 30; age 21.9 ± 2.4 years) and older adults (n = 30; age 71.9 ± 6.4 years) were recruited. Postural control after stepping down was measured with and without performing a concurrent auditory response task. Measurement included: (1) reaction time and (2) error rate in performing the cognitive task; (3) total sway path and (4) total sway area after stepping down. Our findings showed that the older adults had significantly longer reaction times and higher error rates than the younger subjects in both the single-tasking and dual-tasking conditions. The older adults had significantly longer reaction times and higher error rates when dual-tasking compared with single-tasking, but the younger adults did not. The older adults demonstrated significantly less total sway path, but larger total sway area in single-leg stance after stepping down than the young adults. The older adults showed no significant change in total sway path and area between the dual-tasking and when compared with single-tasking conditions, while the younger adults showed significant decreases in sway. Older adults prioritize postural control by sacrificing cognitive performance when faced with dual-tasking.

  4. The brain stem function in patients with brain bladder; Clinical evaluation using dynamic CT scan and auditory brainstem response

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Toshihiro (Yokohama City Univ. (Japan). Faculty of Medicine)

    1990-11-01

    A syndrome of detrusor-sphincter dyssynergia (DSD) is occasionally found in patients with brain bladder. To evaluate the brain stem function in cases of brain bladder, urodynamic study, dynamic CT scan of the brain stem (DCT) and auditory brainstem response (ABR) were performed. The region of interest of DCT aimed at the posterolateral portion of the pons. The results were analysed in contrast with the presense of DSD in urodynamic study. DCT studies were performed in 13 cases with various brain diseases and 5 control cases without neurological diseases. Abnormal patterns of the time-density curve consisted of low peak value, prolongation of filling time and low rapid washout ratio (low clearance ratio) of the contrast medium. Four of 6 cases with DSD showed at least one of the abnormal patterns of the time-density curve bilaterally. In 7 cases without DSD none showed bilateral abnormality of the curve and in 2 of 7 cases only unilateral abnormality was found. ABR was performed in 8 patients with brain diseases. The interpeak latency of the wave I-V (I-V IPL) was considered to be prolonged in 2 cases with DSD compared to that of 4 without DSD. In 2 cases with DSD who had normal DCT findings, measurement of the I-V IPL was impossible due to abnormal pattern of the ABR wave. Above mentioned results suggests the presence of functional disturbance at the posterolateral portion of the pons in cases of brain bladder with DSD. (author).

  5. Piracetam-induced changes on the brainstem auditory response in anesthetized juvenile rhesus monkeys (Macaca mulatta). Report of two clinical cases.

    Science.gov (United States)

    Durand-Rivera, A; Gonzalez-Pina, R; Hernandez-Godinez, B; Ibanez-Contreras, A; Bueno-Nava, A; Alfaro-Rodriguez, A

    2012-10-01

    We describe two clinical cases and examine the effects of piracetam on the brainstem auditory response in infantile female rhesus monkeys (Macaca mulatta). We found that the interwave intervals show a greater reduction in a 3-year-old rhesus monkey compared to a 1-year-old rhesus monkey. In this report, we discuss the significance of these observations. © 2012 John Wiley & Sons A/S.

  6. Aberrant brain response after auditory deviance in PTSD compared to trauma controls: An EEG study

    NARCIS (Netherlands)

    Bangel, Katrin A.; van Buschbach, Susanne; Smit, Dirk J. A.; Mazaheri, Ali; Olff, Miranda

    2017-01-01

    Part of the symptomatology of post-traumatic stress disorder (PTSD) are alterations in arousal and reactivity which could be related to a maladaptive increase in the automated sensory change detection system of the brain. In the current EEG study we investigated whether the brain's response to a

  7. Neural responses in the primary auditory cortex of freely behaving cats while discriminating fast and slow click-trains.

    Science.gov (United States)

    Dong, Chao; Qin, Ling; Liu, Yongchun; Zhang, Xinan; Sato, Yu

    2011-01-01

    Repeated acoustic events are ubiquitous temporal features of natural sounds. To reveal the neural representation of the sound repetition rate, a number of electrophysiological studies have been conducted on various mammals and it has been proposed that both the spike-time and firing rate of primary auditory cortex (A1) neurons encode the repetition rate. However, previous studies rarely examined how the experimental animals perceive the difference in the sound repetition rate, and a caveat to these experiments is that they compared physiological data obtained from animals with psychophysical data obtained from humans. In this study, for the first time, we directly investigated acoustic perception and the underlying neural mechanisms in the same experimental animal by examining spike activities in the A1 of free-moving cats while performing a Go/No-go task to discriminate the click-trains at different repetition rates (12.5-200 Hz). As reported by previous studies on passively listening animals, A1 neurons showed both synchronized and non-synchronized responses to the click-trains. We further found that the neural performance estimated from the precise temporal information of synchronized units was good enough to distinguish all 16.7-200 Hz from the 12.5 Hz repetition rate; however, the cats showed declining behavioral performance with the decrease of the target repetition rate, indicating an increase of difficulty in discriminating two slower click-trains. Such behavioral performance was well explained by the firing rate of some synchronized and non-synchronized units. Trial-by-trial analysis indicated that A1 activity was not affected by the cat's judgment of behavioral response. Our results suggest that the main function of A1 is to effectively represent temporal signals using both spike timing and firing rate, while the cats may read out the rate-coding information to perform the task in this experiment.

  8. Neural responses in the primary auditory cortex of freely behaving cats while discriminating fast and slow click-trains.

    Directory of Open Access Journals (Sweden)

    Chao Dong

    Full Text Available Repeated acoustic events are ubiquitous temporal features of natural sounds. To reveal the neural representation of the sound repetition rate, a number of electrophysiological studies have been conducted on various mammals and it has been proposed that both the spike-time and firing rate of primary auditory cortex (A1 neurons encode the repetition rate. However, previous studies rarely examined how the experimental animals perceive the difference in the sound repetition rate, and a caveat to these experiments is that they compared physiological data obtained from animals with psychophysical data obtained from humans. In this study, for the first time, we directly investigated acoustic perception and the underlying neural mechanisms in the same experimental animal by examining spike activities in the A1 of free-moving cats while performing a Go/No-go task to discriminate the click-trains at different repetition rates (12.5-200 Hz. As reported by previous studies on passively listening animals, A1 neurons showed both synchronized and non-synchronized responses to the click-trains. We further found that the neural performance estimated from the precise temporal information of synchronized units was good enough to distinguish all 16.7-200 Hz from the 12.5 Hz repetition rate; however, the cats showed declining behavioral performance with the decrease of the target repetition rate, indicating an increase of difficulty in discriminating two slower click-trains. Such behavioral performance was well explained by the firing rate of some synchronized and non-synchronized units. Trial-by-trial analysis indicated that A1 activity was not affected by the cat's judgment of behavioral response. Our results suggest that the main function of A1 is to effectively represent temporal signals using both spike timing and firing rate, while the cats may read out the rate-coding information to perform the task in this experiment.

  9. Dynamics of Neural Responses in Ferret Primary Auditory Cortex: I. Spectro-Temporal Response Field Characterization by Dynamic Ripple Spectra

    National Research Council Canada - National Science Library

    Depireux, Didier A; Simon, Jonathan Z; Klein, David J; Shamma, Shihab A

    1999-01-01

    .... It is calculated here from the responses to elementary 'ripples,' a family of sounds with drifting, sinusoidal, spectral envelopes - the complex spectrotemporal envelope of any broadband, dynamic...

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    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

  12. A NMDA receptor antagonist, MK-801 impairs consolidating extinction of auditory conditioned fear responses in a Pavlovian model.

    Directory of Open Access Journals (Sweden)

    Jun-Li Liu

    Full Text Available BACKGROUND: In auditory fear conditioning, repeated presentation of the tone in the absence of shock leads to extinction of the acquired fear responses. The glutamate N-methyl-D-aspartate receptor (NMDAR is thought to be involved in the extinction of the conditioned fear responses, but its detailed role in initiating and consolidating or maintaining the fear extinction memory is unclear. Here we investigated this issue by using a NMDAR antagonist, MK-801. METHODS/MAIN FINDINGS: The effects of immediate (beginning at 10 min after the conditioning and delayed (beginning at 24 h after conditioning extinctions were first compared with the finding that delayed extinction caused a better and long-lasting (still significant on the 20(th day after extinction depression on the conditioned fear responses. In a second experiment, MK-801 was intraperitoneally (i.p. injected at 40 min before, 4 h or 12 h after the delayed extinction, corresponding to critical time points for initiating, consolidating or maintaining the fear extinction memory. i.p. injection of MK-801 at either 40 min before or 4 h after delayed extinction resulted in an impairment of initiating and consolidating fear extinction memory, which caused a long lasting increased freezing score that was still significant on the 7th day after extinction, compared with extinction group. However, MK-801 administered at 12 h after the delayed extinction, when robust consolidation has been occurred and stabilized, did not affect the established extinction memory. Furthermore, the changed freezing behaviors was not due to an alteration in general anxiety levels, since MK-801 treatment had no effect on the percentage of open-arm time or open-arm entries in an Elevated Plus Maze (EPM task. CONCLUSIONS/SIGNIFICANCE: Our data suggested that the activation of NMDARs plays important role in initiation and consolidation but not maintenance of fear extinction memory. Together with the fact that NMDA receptor is

  13. 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...

  14. Tai Chi practitioners have better postural control and selective attention in stepping down with and without a concurrent auditory response task.

    Science.gov (United States)

    Lu, Xi; Siu, Ka-Chun; Fu, Siu N; Hui-Chan, Christina W Y; Tsang, William W N

    2013-08-01

    To compare the performance of older experienced Tai Chi practitioners and healthy controls in dual-task versus single-task paradigms, namely stepping down with and without performing an auditory response task, a cross-sectional study was conducted in the Center for East-meets-West in Rehabilitation Sciences at The Hong Kong Polytechnic University, Hong Kong. Twenty-eight Tai Chi practitioners (73.6 ± 4.2 years) and 30 healthy control subjects (72.4 ± 6.1 years) were recruited. Participants were asked to step down from a 19-cm-high platform and maintain a single-leg stance for 10 s with and without a concurrent cognitive task. The cognitive task was an auditory Stroop test in which the participants were required to respond to different tones of voices regardless of their word meanings. Postural stability after stepping down under single- and dual-task paradigms, in terms of excursion of the subject's center of pressure (COP) and cognitive performance, was measured for comparison between the two groups. Our findings demonstrated significant between-group differences in more outcome measures during dual-task than single-task performance. Thus, the auditory Stroop test showed that Tai Chi practitioners achieved not only significantly less error rate in single-task, but also significantly faster reaction time in dual-task, when compared with healthy controls similar in age and other relevant demographics. Similarly, the stepping-down task showed that Tai Chi practitioners not only displayed significantly less COP sway area in single-task, but also significantly less COP sway path than healthy controls in dual-task. These results showed that Tai Chi practitioners achieved better postural stability after stepping down as well as better performance in auditory response task than healthy controls. The improved performance that was magnified by dual motor-cognitive task performance may point to the benefits of Tai Chi being a mind-and-body exercise.

  15. Preservation of auditory brainstem response thresholds after cochleostomy and titanium microactuator implantation in the lateral wall of cat scala tympani.

    Science.gov (United States)

    Lesinski, S George; Prewitt, Jessica; Bray, Victor; Aravamudhan, Radhika; Bermeo Blanco, Oscar A; Farmer-Fedor, Brenda L; Ward, Jonette A

    2014-04-01

    The safety of implanting a titanium microactuator into the lateral wall of cat scala tympani was assessed by comparing preoperative and postoperative auditory brainstem response (ABR) thresholds for 1 to 3 months. The safety of directly stimulating cochlear perilymph with an implantable hearing system requires maintaining preoperative hearing levels. This cat study is an essential step in the development of the next generation of fully implantable hearing devices for humans. Following GLP surgical standards, a 1-mm cochleostomy was drilled into the lateral wall of the scala tympani, and a nonfunctioning titanium anchor/microactuator assembly was inserted in 8 cats. The scala media was damaged in the 1 cat. ABR thresholds with click and 4- and 8-kHz stimuli were measured preoperatively and compared with postoperative thresholds at 1, 2, and 3 months. Nonimplanted ear thresholds were also measured to establish statistical significance for threshold shifts (>28.4 dB). Two audiologists independently interpreted thresholds. Postoperatively, 7 cats implanted in the scala tympani demonstrated no significant ABR threshold shift for click stimulus; one shifted ABR thresholds to 4- and 8-kHz stimuli. The eighth cat, with surgical damage to the scala media, maintained stable click threshold but had a significant shift to 4- and 8-kHz stimuli. This cat study provides no evidence of worsening hearing thresholds after fenestration of the scala tympani and insertion of a titanium anchor/microactuator, provided there is no surgical trauma to the scala media and the implanted device is securely anchored in the cochleostomy. These 2 issues have been resolved in the development of a fully implantable hearing system for humans. The long-term hearing stability (combined with histologic studies) reaffirm that the microactuator is well tolerated by the cat cochlea.

  16. Sensitivity of cortical auditory evoked potential detection for hearing-impaired infants in response to short speech sounds

    Directory of Open Access Journals (Sweden)

    Bram Van Dun

    2012-01-01

    Full Text Available

    Background: Cortical auditory evoked potentials (CAEPs are an emerging tool for hearing aid fitting evaluation in young children who cannot provide reliable behavioral feedback. It is therefore useful to determine the relationship between the sensation level of speech sounds and the detection sensitivity of CAEPs.

    Design and methods: Twenty-five sensorineurally hearing impaired infants with an age range of 8 to 30 months were tested once, 18 aided and 7 unaided. First, behavioral thresholds of speech stimuli /m/, /g/, and /t/ were determined using visual reinforcement orientation audiometry (VROA. Afterwards, the same speech stimuli were presented at 55, 65, and 75 dB SPL, and CAEP recordings were made. An automatic statistical detection paradigm was used for CAEP detection.

    Results: For sensation levels above 0, 10, and 20 dB respectively, detection sensitivities were equal to 72 ± 10, 75 ± 10, and 78 ± 12%. In 79% of the cases, automatic detection p-values became smaller when the sensation level was increased by 10 dB.

    Conclusions: The results of this study suggest that the presence or absence of CAEPs can provide some indication of the audibility of a speech sound for infants with sensorineural hearing loss. The detection of a CAEP provides confidence, to a degree commensurate with the detection probability, that the infant is detecting that sound at the level presented. When testing infants where the audibility of speech sounds has not been established behaviorally, the lack of a cortical response indicates the possibility, but by no means a certainty, that the sensation level is 10 dB or less.

  17. Auditory steady-state response thresholds in adults with conductive and mild to moderate sensorineural hearing loss.

    Science.gov (United States)

    Hosseinabadi, Reza; Jafarzadeh, Sadegh

    2015-01-01

    The Auditory steady state response (ASSR) provides a frequency-specific and automatic assessment of hearing sensitivity and is used in infants and difficult-to-test adults. The aim of this study was to compare the ASSR thresholds among various types (normal, conductive, and sensorineural), degree (normal, mild, and moderate), and configuration (flat and sloping) of hearing sensitivity, and measuring the cutoff point between normal condition and hearing loss for different frequencies. This clinical trial was performed in Iran and included patients who were referred from Ear, Nose, and Throat Department. A total of 54 adults (27 with sensorineural hearing loss, 17 with conductive hearing losses, and 10 with normal hearing) were randomly chosen to participate in our study. The type and degree of hearing loss were determined through testing by otoscopy, tympanometry, acoustic reflex, and pure tone audiometry. Then the ASSR was tested at carrier frequencies of 500, 1000, 2000, and 4000 Hz. The ASSR accurately estimates the behavioral thresholds as well as flat and sloping configurations. There was no correlation between types of hearing loss and difference of behavioral and ASSR thresholds (P = 0.69). The difference between ASSR and behavioral thresholds decreased as severity of hearing loss increased. The 40, 35, 30, and 35 dB could be considered as cutoffs between normal hearing and hearing loss for 500, 1000, 2000, and 4000 Hz, respectively. The ASSR can accurately predict the degree and configuration of hearing loss and discriminate the normal hearing from mild or moderate hearing loss and mild from moderate hearing loss, except for 500 Hz. The Air-conducted ASSR could not define the type of hearing loss.

  18. Optical measurement of the weak non-linearity in the eardrum vibration response to auditory stimuli

    Science.gov (United States)

    Aerts, Johan

    The mammalian hearing organ consists of the external ear (auricle and ear canal) followed by the middle ear (eardrum and ossicles) and the inner ear (cochlea). Its function is to convert the incoming sound waves and convert them into nerve pulses which are processed in the final stage by the brain. The main task of the external and middle ear is to concentrate the incoming sound waves on a smaller surface to reduce the loss that would normally occur in transmission from air to inner ear fluid. In the past it has been shown that this is a linear process, thus without serious distortions, for sound waves going up to pressures of 130 dB SPL (˜90 Pa). However, at large pressure changes up to several kPa, the middle ear movement clearly shows non-linear behaviour. Thus, it is possible that some small non-linear distortions are also present in the middle ear vibration at lower sound pressures. In this thesis a sensitive measurement set-up is presented to detect this weak non-linear behaviour. Essentially, this set-up consists of a loud-speaker which excites the middle ear, and the resulting vibration is measured with an heterodyne vibrometer. The use of specially designed acoustic excitation signals (odd random phase multisines) enables the separation of the linear and non-linear response. The application of this technique on the middle ear demonstrates that there are already non-linear distortions present in the vibration of the middle ear at a sound pressure of 93 dB SPL. This non-linear component also grows strongly with increasing sound pressure. Knowledge of this non-linear component can contribute to the improvement of modern hearing aids, which operate at higher sound pressures where the non-linearities could distort the signal considerably. It is also important to know the contribution of middle ear non-linearity to otoacoustic emissions. This are non-linearities caused by the active feedback amplifier in the inner ear, and can be detected in the external and

  19. Intracerebral evidence of rhythm transform in the human auditory cortex.

    Science.gov (United States)

    Nozaradan, Sylvie; Mouraux, André; Jonas, Jacques; Colnat-Coulbois, Sophie; Rossion, Bruno; Maillard, Louis

    2017-07-01

    Musical entrainment is shared by all human cultures and the perception of a periodic beat is a cornerstone of this entrainment behavior. Here, we investigated whether beat perception might have its roots in the earliest stages of auditory cortical processing. Local field potentials were recorded from 8 patients implanted with depth-electrodes in Heschl's gyrus and the planum temporale (55 recording sites in total), usually considered as human primary and secondary auditory cortices. Using a frequency-tagging approach, we show that both low-frequency (30 Hz) neural activities in these structures faithfully track auditory rhythms through frequency-locking to the rhythm envelope. A selective gain in amplitude of the response frequency-locked to the beat frequency was observed for the low-frequency activities but not for the high-frequency activities, and was sharper in the planum temporale, especially for the more challenging syncopated rhythm. Hence, this gain process is not systematic in all activities produced in these areas and depends on the complexity of the rhythmic input. Moreover, this gain was disrupted when the rhythm was presented at fast speed, revealing low-pass response properties which could account for the propensity to perceive a beat only within the musical tempo range. Together, these observations show that, even though part of these neural transforms of rhythms could already take place in subcortical auditory processes, the earliest auditory cortical processes shape the neural representation of rhythmic inputs in favor of the emergence of a periodic beat.

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

    Science.gov (United States)

    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.

  1. Neural plasticity expressed in central auditory structures with and without tinnitus

    Directory of Open Access Journals (Sweden)

    Larry E Roberts

    2012-05-01

    Full Text Available Sensory training therapies for tinnitus are based on the assumption that, notwithstanding neural changes related to tinnitus, auditory training can alter the response properties of neurons in auditory pathways. To address this question, we investigated whether brain changes induced by sensory training in tinnitus sufferers and measured by EEG are similar to those induced in age and hearing loss matched individuals without tinnitus trained on the same auditory task. Auditory training was given using a 5 kHz 40-Hz amplitude-modulated sound that was in the tinnitus frequency region of the tinnitus subjects and enabled extraction of the 40-Hz auditory steady-state response (ASSR and P2 transient response known to localize to primary and nonprimary auditory cortex, respectively. P2 amplitude increased with training equally in participants with tinnitus and in control subjects, suggesting normal remodeling of nonprimary auditory regions in tinnitus. However, training-induced changes in the ASSR differed between the tinnitus and control groups. In controls ASSR phase advanced toward the stimulus waveform by about ten degrees over training, in agreement with previous results obtained in young normal hearing individuals. However, ASSR phase did not change significantly with training in the tinnitus group, although some participants showed phase shifts resembling controls. On the other hand, ASSR amplitude increased with training in the tinnitus group, whereas in controls this response (which is difficult to remodel in young normal hearing subjects did not change with training. These results suggest that neural changes related to tinnitus altered how neural plasticity was expressed in the region of primary but not nonprimary auditory cortex. Auditory training did not reduce tinnitus loudness although a small effect on the tinnitus spectrum was detected.

  2. Adaptation in the auditory system: an overview

    Directory of Open Access Journals (Sweden)

    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.

  3. Analytic approaches to atomic response properties

    International Nuclear Information System (INIS)

    Lamm, E.E.

    1980-01-01

    Many important response properties, e.g., multipole polarizabilites and sum rules, photodetachment cross sections, and closely-related long-range dispersion force coefficients, are insensitive to details of electronic structure. In this investigation, analytic asymptotic theories of atomic response properties are constructed that yield results as accurate as those obtained by more elaborate numerical methods. In the first chapter, a novel and simple method is used to determined the multipole sum rules S/sub l/(-k), for positive and negative values of k, of the hydrogen atom and the hydrogen negative ion in the asymptotic approximation. In the second chapter, an analytically-tractable extended asymptotic model for the response properites of weakly-bound anions is proposed and the multipole polarizability, multipole sum rules, and photodetachment cross section determined by the model are computed analytically. Dipole polarizabilities and photodetachment cross sections determined from the model for Li-, Na-, and K- are compared with the numercal results of Moores and Norcross. Agreement is typically within 15% if the pseudopotential is included. In the third chapter a comprehensive and unified treatment of atomic multipole oscillator strengths, dynamic multipole polarizabilites, and dispersion force constants in a variety of Coulomb-like approximations is presented. A theoretically and computationally superior modification of the original Bates-Damgaard (BD) procedure, referred to here as simply the Coulomb approximation (CA), is introduced. An analytic expression for the dynamic multipole polarizability is found which contains as special cases this quantity within the CA, the extended Coulomb approximation (ECA) of Adelman and Szabo, and the quantum defect orbital (QDO) method of Simons

  4. Maps of the Auditory Cortex.

    Science.gov (United States)

    Brewer, Alyssa A; Barton, Brian

    2016-07-08

    One of the fundamental properties of the mammalian brain is that sensory regions of cortex are formed of multiple, functionally specialized cortical field maps (CFMs). Each CFM comprises two orthogonal topographical representations, reflecting two essential aspects of sensory space. In auditory cortex, auditory field maps (AFMs) are defined by the combination of tonotopic gradients, representing the spectral aspects of sound (i.e., tones), with orthogonal periodotopic gradients, representing the temporal aspects of sound (i.e., period or temporal envelope). Converging evidence from cytoarchitectural and neuroimaging measurements underlies the definition of 11 AFMs across core and belt regions of human auditory cortex, with likely homology to those of macaque. On a macrostructural level, AFMs are grouped into cloverleaf clusters, an organizational structure also seen in visual cortex. Future research can now use these AFMs to investigate specific stages of auditory processing, key for understanding behaviors such as speech perception and multimodal sensory integration.

  5. Potenciais evocados auditivos de tronco encefálico em frentistas Auditory brainstem response in gas station attendants

    Directory of Open Access Journals (Sweden)

    Lenita da Silva Quevedo

    2012-12-01

    Full Text Available A ototoxidade dos solventes orgânicos pode atingir o sistema auditivo a nível coclear e retrococlear. OBJETIVO: Avaliar a integridade neurofisiológica do sistema auditivo até tronco cerebral por meio do PEATE. MÉTODO: Estudo prospectivo. Estudados frentistas de três postos de gasolina da cidade de Santa Maria/RS. A amostra ficou composta por 21 sujeitos, que foram avaliados por meio de potenciais evocados auditivos de tronco encefálico. RESULTADOS: Alteração nas latências absolutas das ondas I e III e em todas as latências interpicos, na orelha direita. Na orelha esquerda houve alteração na latência absoluta de todas as ondas, e em todos os intervalos interpicos. Alteração na diferença interaural da onda V foi verificada em 19% dos sujeitos. No grupo exposto há mais de cinco anos, foram estatisticamente significantes o número de sujeitos com alteração: no intervalo interpico I-V da orelha direita; na latência absoluta da onda I e no intervalo interpico III-V da orelha esquerda. CONCLUSÃO: A exposição a combustíveis pode causar alterações no sistema auditivo central.Ototoxicity of organic solvents can affect the hearing system up to the cochlea level and the central structures of hearing. OBJECTIVE: To evaluate the neurophysiological integrity of the hearing system in subjects exposed to fuels using ABR. METHOD: Prospective study. We evaluated attendants from three gas stations in Santa Maria/RS. The sample had 21 subjects, who were evaluated by auditory brainstem response. RESULTS: We found an alteration in the absolute latencies of Waves I and III and in all the interpeak latencies, in the right ear. In the left ear there was a change in the absolute latencies of all Waves, and in all the interpeak intervals. A change in the interaural difference of Wave V was found in 19% of the individuals. In the group exposed for more than five years, there were subjects with a statistically significant changes: in the I

  6. Petroleum geochemical responses to reservoir rock properties

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, B.; Larter, S.R. [Calgary Univ., AB (Canada)

    2008-07-01

    Reservoir geochemistry is used to study petroleum basin development, petroleum mixing, and alterations. In this study, polar non-hydrocarbons were used as proxies for describing reservoir properties sensitive to fluid-rock interactions. A core flood experiment was conducted on a Carboniferous siltstone core obtained from a site in the United Kingdom. Core samples were then obtained from a typical upper shoreface in a North Sea oilfield. The samples were extracted with a dichloromethane and methanol mixture. Alkylcarbazoles and alkylfluorenones were then isolated from the samples. Compositional changes along the core were also investigated. Polar non hydrocarbons were studied using a wireline gamma ray log. The strongest deflections were observed in the basal coarsening upwards unit. The study demonstrated the correlations between molecular markers, and indicated that molecular parameters can be used to differentiate between clean sand units and adjacent coarsening upward muddy sand sequences. It was concluded that reservoir geochemical parameters can provide an independent response to properties defined by petrophysical methods. 6 refs., 2 figs.

  7. Functional dissociation between regularity encoding and deviance detection along the auditory hierarchy.

    Science.gov (United States)

    Aghamolaei, Maryam; Zarnowiec, Katarzyna; Grimm, Sabine; Escera, Carles

    2016-02-01

    Auditory deviance detection based on regularity encoding appears as one of the basic functional properties of the auditory system. It has traditionally been assessed with the mismatch negativity (MMN) long-latency component of the auditory evoked potential (AEP). Recent studies have found earlier correlates of deviance detection based on regularity encoding. They occur in humans in the first 50 ms after sound onset, at the level of the middle-latency response of the AEP, and parallel findings of stimulus-specific adaptation observed in animal studies. However, the functional relationship between these different levels of regularity encoding and deviance detection along the auditory hierarchy has not yet been clarified. Here we addressed this issue by examining deviant-related responses at different levels of the auditory hierarchy to stimulus changes varying in their degree of deviation regarding the spatial location of a repeated standard stimulus. Auditory stimuli were presented randomly from five loudspeakers at azimuthal angles of 0°, 12°, 24°, 36° and 48° during oddball and reversed-oddball conditions. Middle-latency responses and MMN were measured. Our results revealed that middle-latency responses were sensitive to deviance but not the degree of deviation, whereas the MMN amplitude increased as a function of deviance magnitude. These findings indicated that acoustic regularity can be encoded at the level of the middle-latency response but that it takes a higher step in the auditory hierarchy for deviance magnitude to be encoded, thus providing a functional dissociation between regularity encoding and deviance detection along the auditory hierarchy. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  8. Segregation of Visual Response Properties in the Mouse Superior Colliculus and Their Modulation during Locomotion

    Science.gov (United States)

    2017-01-01

    The superior colliculus (SC) receives direct input from the retina and integrates it with information about sound, touch, and state of the animal that is relayed from other parts of the brain to initiate specific behavioral outcomes. The superficial SC layers (sSC) contain cells that respond to visual stimuli, whereas the deep SC layers (dSC) contain cells that also respond to auditory and somatosensory stimuli. Here, we used a large-scale silicon probe recording system to examine the visual response properties of SC cells of head-fixed and alert male mice. We found cells with diverse response properties including: (1) orientation/direction-selective (OS/DS) cells with a firing rate that is suppressed by drifting sinusoidal gratings (negative OS/DS cells); (2) suppressed-by-contrast cells; (3) cells with complex-like spatial summation nonlinearity; and (4) cells with Y-like spatial summation nonlinearity. We also found specific response properties that are enriched in different depths of the SC. The sSC is enriched with cells with small RFs, high evoked firing rates (FRs), and sustained temporal responses, whereas the dSC is enriched with the negative OS/DS cells and with cells with large RFs, low evoked FRs, and transient temporal responses. Locomotion modulates the activity of the SC cells both additively and multiplicatively and changes the preferred spatial frequency of some SC cells. These results provide the first description of the negative OS/DS cells and demonstrate that the SC segregates cells with different response properties and that the behavioral state of a mouse affects SC activity. SIGNIFICANCE STATEMENT The superior colliculus (SC) receives visual input from the retina in its superficial layers (sSC) and induces eye/head-orientating movements and innate defensive responses in its deeper layers (dSC). Despite their importance, very little is known about the visual response properties of dSC neurons. Using high-density electrode recordings and novel

  9. 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.

  10. Did You Listen to the Beat? Auditory Steady-State Responses in the Human Electroencephalogram at 4 and 7 Hz Modulation Rates Reflect Selective Attention.

    Science.gov (United States)

    Jaeger, Manuela; Bleichner, Martin G; Bauer, Anna-Katharina R; Mirkovic, Bojana; Debener, Stefan

    2018-02-27

    The acoustic envelope of human speech correlates with the syllabic rate (4-8 Hz) and carries important information for intelligibility, which is typically compromised in multi-talker, noisy environments. In order to better understand the dynamics of selective auditory attention to low frequency modulated sound sources, we conducted a two-stream auditory steady-state response (ASSR) selective attention electroencephalogram (EEG) study. The two streams consisted of 4 and 7 Hz amplitude and frequency modulated sounds presented from the left and right side. One of two streams had to be attended while the other had to be ignored. The attended stream always contained a target, allowing for the behavioral confirmation of the attention manipulation. EEG ASSR power analysis revealed a significant increase in 7 Hz power for the attend compared to the ignore conditions. There was no significant difference in 4 Hz power when the 4 Hz stream had to be attended compared to when it had to be ignored. This lack of 4 Hz attention modulation could be explained by a distracting effect of a third frequency at 3 Hz (beat frequency) perceivable when the 4 and 7 Hz streams are presented simultaneously. Taken together our results show that low frequency modulations at syllabic rate are modulated by selective spatial attention. Whether attention effects act as enhancement of the attended stream or suppression of to be ignored stream may depend on how well auditory streams can be segregated.

  11. 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...

  12. Comparison of peripheral compression estimates using auditory steady-state responses (ASSR) and distortion product otoacoustic emissions (DPOAE)

    DEFF Research Database (Denmark)

    Encina Llamas, Gerard; Epp, Bastian; Dau, Torsten

    The healthy auditory system shows a compressive input/output (I/O) function as a result of healthy outer-hair cell function. Hearing impairment often leads to a decrease in sensitivity and a reduction of compression, mainly caused by loss of inner and/or outer hair cells. Compression is commonly...... (DPOAEs) recordings. Results show compressive ASSR I/O functions for NH subjects. For HI subjects, ASSR reveal the loss of sensitivity at low stimulus levels. Growth slopes are smaller (more compressive) in ASSR than in DPOAE I/O functions....

  13. Auditory prediction during speaking and listening.

    Science.gov (United States)

    Sato, Marc; Shiller, Douglas M

    2018-02-02

    In the present EEG study, the role of auditory prediction in speech was explored through the comparison of auditory cortical responses during active speaking and passive listening to the same acoustic speech signals. Two manipulations of sensory prediction accuracy were used during the speaking task: (1) a real-time change in vowel F1 feedback (reducing prediction accuracy relative to unaltered feedback) and (2) presenting a stable auditory target rather than a visual cue to speak (enhancing auditory prediction accuracy during baseline productions, and potentially enhancing the perturbing effect of altered feedback). While subjects compensated for the F1 manipulation, no difference between the auditory-cue and visual-cue conditions were found. Under visually-cued conditions, reduced N1/P2 amplitude was observed during speaking vs. listening, reflecting a motor-to-sensory prediction. In addition, a significant correlation was observed between the magnitude of behavioral compensatory F1 response and the magnitude of this speaking induced suppression (SIS) for P2 during the altered auditory feedback phase, where a stronger compensatory decrease in F1 was associated with a stronger the SIS effect. Finally, under the auditory-cued condition, an auditory repetition-suppression effect was observed in N1/P2 amplitude during the listening task but not active speaking, suggesting that auditory predictive processes during speaking and passive listening are functionally distinct. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Auditory short-term memory trace formation for nonspeech and speech in SLI and dyslexia as indexed by the N100 and mismatch negativity electrophysiological responses.

    Science.gov (United States)

    Tuomainen, Outi T

    2015-04-15

    This study investigates nonspeech and speech processing in specific language impairment (SLI) and dyslexia. We used a passive mismatch negativity (MMN) task to tap automatic brain responses and an active behavioural task to tap attended discrimination of nonspeech and speech sounds. Using the roving standard MMN paradigm, we varied the number of standards ('few' vs. 'many') to investigate the effect of sound repetition on N100 and MMN responses. The results revealed that the SLI group needed more repetitions than dyslexics and controls to create a strong enough sensory trace to elicit MMN. In contrast, in the behavioural task, we observed good discrimination of speech and nonspeech in all groups. The findings indicate that auditory processing deficits in SLI and dyslexia are dissociable and that memory trace formation may be implicated in SLI.

  15. Encoding of natural and artificial stimuli in the auditory midbrain

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  17. Bayesian Modeling of the Dynamics of Phase Modulations and their Application to Auditory Evoked Responses at Different Loudness Scales

    Directory of Open Access Journals (Sweden)

    Zeinab eMortezapouraghdam

    2016-01-01

    Full Text Available We study the effect of long-term habituation signatures of auditory selective attention reflected in the instantaneous phase information of the auditory event-related potentials (ERPs at four distinct stimuli levels of 60dB SPL, 70dB SPL, 80dB SPL and 90dB SPL. The analysis is based on the single-trial level. The effect of habituation can be observed in terms of the changes (jitter in the instantaneous phase information of ERPs. In particular, the absence of habituation is correlated with a consistently high phase synchronization over ERP trials.We estimate the changes in phase concentration over trials using a Bayesian approach, in which the phase is modeled as being drawn from a von Mises distribution with a concentration parameter which varies smoothly over trials. The smoothness assumption reflects the fact that habituation is a gradual process.We differentiate between different stimuli based on the relative changes and absolute values of the estimated concentration parameter using the proposed Bayesian model.

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

    Science.gov (United States)

    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

  19. Time-varying auditory gain control in response to double-pulse stimuli in harbour porpoises is not mediated by a stapedial reflex

    Directory of Open Access Journals (Sweden)

    Asger Emil Munch Schrøder

    2017-04-01

    Full Text Available Echolocating animals reduce their output level and hearing sensitivity with decreasing echo delays, presumably to stabilize the perceived echo intensity during target approaches. In bats, this variation in hearing sensitivity is formed by a call-induced stapedial reflex that tapers off over time after the call. Here, we test the hypothesis that a similar mechanism exists in toothed whales by subjecting a trained harbour porpoise to a series of double sound pulses varying in delay and frequency, while measuring the magnitudes of the evoked auditory brainstem responses (ABRs. We find that the recovery of the ABR to the second pulse is frequency dependent, and that a stapedial reflex therefore cannot account for the reduced hearing sensitivity at short pulse delays. We propose that toothed whale auditory time-varying gain control during echolocation is not enabled by the middle ear as in bats, but rather by frequency-dependent mechanisms such as forward masking and perhaps higher-order control of efferent feedback to the outer hair cells.

  20. Laminar differences in response to simple and spectro-temporally complex sounds in the primary auditory cortex of ketamine-anesthetized gerbils.

    Directory of Open Access Journals (Sweden)

    Markus K Schaefer

    Full Text Available In mammals, acoustic communication plays an important role during social behaviors. Despite their ethological relevance, the mechanisms by which the auditory cortex represents different communication call properties remain elusive. Recent studies have pointed out that communication-sound encoding could be based on discharge patterns of neuronal populations. Following this idea, we investigated whether the activity of local neuronal networks, such as those occurring within individual cortical columns, is sufficient for distinguishing between sounds that differed in their spectro-temporal properties. To accomplish this aim, we analyzed simple pure-tone and complex communication call elicited multi-unit activity (MUA as well as local field potentials (LFP, and current source density (CSD waveforms at the single-layer and columnar level from the primary auditory cortex of anesthetized Mongolian gerbils. Multi-dimensional scaling analysis was used to evaluate the degree of "call-specificity" in the evoked activity. The results showed that whole laminar profiles segregated 1.8-2.6 times better across calls than single-layer activity. Also, laminar LFP and CSD profiles segregated better than MUA profiles. Significant differences between CSD profiles evoked by different sounds were more pronounced at mid and late latencies in the granular and infragranular layers and these differences were based on the absence and/or presence of current sinks and on sink timing. The stimulus-specific activity patterns observed within cortical columns suggests that the joint activity of local cortical populations (as local as single columns could indeed be important for encoding sounds that differ in their acoustic attributes.

  1. Neuromechanistic Model of Auditory Bistability.

    Directory of Open Access Journals (Sweden)

    James Rankin

    2015-11-01

    Full Text Available Sequences of higher frequency A and lower frequency B tones repeating in an ABA- triplet pattern are widely used to study auditory streaming. One may experience either an integrated percept, a single ABA-ABA- stream, or a segregated percept, separate but simultaneous streams A-A-A-A- and -B---B--. During minutes-long presentations, subjects may report irregular alternations between these interpretations. We combine neuromechanistic modeling and psychoacoustic experiments to study these persistent alternations and to characterize the effects of manipulating stimulus parameters. Unlike many phenomenological models with abstract, percept-specific competition and fixed inputs, our network model comprises neuronal units with sensory feature dependent inputs that mimic the pulsatile-like A1 responses to tones in the ABA- triplets. It embodies a neuronal computation for percept competition thought to occur beyond primary auditory cortex (A1. Mutual inhibition, adaptation and noise are implemented. We include slow NDMA recurrent excitation for local temporal memory that enables linkage across sound gaps from one triplet to the next. Percepts in our model are identified in the firing patterns of the neuronal units. We predict with the model that manipulations of the frequency difference between tones A and B should affect the dominance durations of the stronger percept, the one dominant a larger fraction of time, more than those of the weaker percept-a property that has been previously established and generalized across several visual bistable paradigms. We confirm the qualitative prediction with our psychoacoustic experiments and use the behavioral data to further constrain and improve the model, achieving quantitative agreement between experimental and modeling results. Our work and model provide a platform that can be extended to consider other stimulus conditions, including the effects of context and volition.

  2. Measuring Behavioral Responses to the Property Tax

    OpenAIRE

    John Deskins; William Fox

    2008-01-01

    This paper focuses on excise effects of the property tax system. The excise effects are, of course, only one element in determining the role that property taxes should play as a revenue source and tell us only part of the story on the tax’s ability to generate revenues, the incidence of the tax and other concerns. In addition to direct excise tax effects, such as on land use and city structure, the tax can indirectly affect choices such as between private and public schools. Some of these eff...

  3. Thresholding of auditory cortical representation by background noise

    Science.gov (United States)

    Liang, Feixue; Bai, Lin; Tao, Huizhong W.; Zhang, Li I.; Xiao, Zhongju

    2014-01-01

    It is generally thought that background noise can mask auditory information. However, how the noise specifically transforms neuronal auditory processing in a level-dependent manner remains to be carefully determined. Here, with in vivo loose-patch cell-attached recordings in layer 4 of the rat primary auditory cortex (A1), we systematically examined how continuous wideband noise of different levels affected receptive field properties of individual neurons. We found that the background noise, when above a certain critical/effective level, resulted in an elevation of intensity threshold for tone-evoked responses. This increase of threshold was linearly dependent on the noise intensity above the critical level. As such, the tonal receptive field (TRF) of individual neurons was translated upward as an entirety toward high intensities along the intensity domain. This resulted in preserved preferred characteristic frequency (CF) and the overall shape of TRF, but reduced frequency responding range and an enhanced frequency selectivity for the same stimulus intensity. Such translational effects on intensity threshold were observed in both excitatory and fast-spiking inhibitory neurons, as well as in both monotonic and nonmonotonic (intensity-tuned) A1 neurons. Our results suggest that in a noise background, fundamental auditory representations are modulated through a background level-dependent linear shifting along intensity domain, which is equivalent to reducing stimulus intensity. PMID:25426029

  4. Thresholding of auditory cortical representation by background noise.

    Science.gov (United States)

    Liang, Feixue; Bai, Lin; Tao, Huizhong W; Zhang, Li I; Xiao, Zhongju

    2014-01-01

    It is generally thought that background noise can mask auditory information. However, how the noise specifically transforms neuronal auditory processing in a level-dependent manner remains to be carefully determined. Here, with in vivo loose-patch cell-attached recordings in layer 4 of the rat primary auditory cortex (A1), we systematically examined how continuous wideband noise of different levels affected receptive field properties of individual neurons. We found that the background noise, when above a certain critical/effective level, resulted in an elevation of intensity threshold for tone-evoked responses. This increase of threshold was linearly dependent on the noise intensity above the critical level. As such, the tonal receptive field (TRF) of individual neurons was translated upward as an entirety toward high intensities along the intensity domain. This resulted in preserved preferred characteristic frequency (CF) and the overall shape of TRF, but reduced frequency responding range and an enhanced frequency selectivity for the same stimulus intensity. Such translational effects on intensity threshold were observed in both excitatory and fast-spiking inhibitory neurons, as well as in both monotonic and nonmonotonic (intensity-tuned) A1 neurons. Our results suggest that in a noise background, fundamental auditory representations are modulated through a background level-dependent linear shifting along intensity domain, which is equivalent to reducing stimulus intensity.

  5. Auditory Perspective Taking

    National Research Council Canada - National Science Library

    Martinson, Eric; Brock, Derek

    2006-01-01

    .... From this knowledge of another's auditory perspective, a conversational partner can then adapt his or her auditory output to overcome a variety of environmental challenges and insure that what is said is intelligible...

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

    Science.gov (United States)

    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

  7. Brain responses and looking behaviour during audiovisual speech integration in infants predict auditory speech comprehension in the second year of life.

    Directory of Open Access Journals (Sweden)

    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.

  8. Prenatal exposure to multiple pesticides is associated with auditory brainstem response at 9months in a cohort study of Chinese infants.

    Science.gov (United States)

    Sturza, Julie; Silver, Monica K; Xu, Lin; Li, Mingyan; Mai, Xiaoqin; Xia, Yankai; Shao, Jie; Lozoff, Betsy; Meeker, John

    2016-01-01

    Pesticides are associated with poorer neurodevelopmental outcomes, but little is known about the effects on sensory functioning. Auditory brainstem response (ABR) and pesticide data were available for 27 healthy, full-term 9-month-old infants participating in a larger study of early iron deficiency and neurodevelopment. Cord blood was analyzed by gas chromatography-mass spectrometry for levels of 20 common pesticides. The ABR forward-masking condition consisted of a click stimulus (masker) delivered via ear canal transducers followed by an identical stimulus delayed by 8, 16, or 64 milliseconds (ms). ABR peak latencies were evaluated as a function of masker-stimulus time interval. Shorter wave latencies reflect faster neural conduction, more mature auditory pathways, and greater degree of myelination. Linear regression models were used to evaluate associations between total number of pesticides detected and ABR outcomes. We considered an additive or synergistic effect of poor iron status by stratifying our analysis by newborn ferritin (based on median split). Infants in the sample were highly exposed to pesticides; a mean of 4.1 pesticides were detected (range 0-9). ABR Wave V latency and central conduction time (CCT) were associated with the number of pesticides detected in cord blood for the 64ms and non-masker conditions. A similar pattern seen for CCT from the 8ms and 16ms conditions, although statistical significance was not reached. Increased pesticide exposure was associated with longer latency. The relation between number of pesticides detected in cord blood and CCT depended on the infant's cord blood ferritin level. Specifically, the relation was present in the lower cord blood ferritin group but not the higher cord blood ferritin group. ABR processing was slower in infants with greater prenatal pesticide exposure, indicating impaired neuromaturation. Infants with lower cord blood ferritin appeared to be more sensitive to the effects of prenatal pesticide

  9. Hair cell regeneration in the avian auditory epithelium.

    Science.gov (United States)

    Stone, Jennifer S; Cotanche, Douglas A

    2007-01-01

    Regeneration of sensory hair cells in the mature avian inner ear was first described just over 20 years ago. Since then, it has been shown that many other non-mammalian species either continually produce new hair cells or regenerate them in response to trauma. However, mammals exhibit limited hair cell regeneration, particularly in the auditory epithelium. In birds and other non-mammals, regenerated hair cells arise from adjacent non-sensory (supporting) cells. Hair cell regeneration was initially described as a proliferative response whereby supporting cells re-enter the mitotic cycle, forming daughter cells that differentiate into either hair cells or supporting cells and thereby restore cytoarchitecture and function in the sensory epithelium. However, further analyses of the avian auditory epithelium (and amphibian vestibular epithelium) revealed a second regenerative mechanism, direct transdifferentiation, during which supporting cells change their gene expression and convert into hair cells without dividing. In the chicken auditory epithelium, these two distinct mechanisms show unique spatial and temporal patterns, suggesting they are differentially regulated. Current efforts are aimed at identifying signals that maintain supporting cells in a quiescent state or direct them to undergo direct transdifferentiation or cell division. Here, we review current knowledge about supporting cell properties and discuss candidate signaling molecules for regulating supporting cell behavior, in quiescence and after damage. While significant advances have been made in understanding regeneration in non-mammals over the last 20 years, we have yet to determine why the mammalian auditory epithelium lacks the ability to regenerate hair cells spontaneously and whether it is even capable of significant regeneration under additional circumstances. The continued study of mechanisms controlling regeneration in the avian auditory epithelium may lead to strategies for inducing

  10. Auditory Connections and Functions of Prefrontal Cortex

    Directory of Open Access Journals (Sweden)

    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.

  11. 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

  12. 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.

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

    Science.gov (United States)

    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.

  14. Post-spike hyperpolarization participates in the formation of auditory behavior-related response patterns of inferior collicular neurons in Hipposideros pratti.

    Science.gov (United States)

    Li, Y-L; Fu, Z-Y; Yang, M-J; Wang, J; Peng, K; Yang, L-J; Tang, J; Chen, Q-C

    2015-03-19

    To probe the mechanism underlying the auditory behavior-related response patterns of inferior collicular neurons to constant frequency-frequency modulation (CF-FM) stimulus in Hipposideros pratti, we studied the role of post-spike hyperpolarization (PSH) in the formation of response patterns. Neurons obtained by in vivo extracellular (N=145) and intracellular (N=171) recordings could be consistently classified into single-on (SO) and double-on (DO) neurons. Using intracellular recording, we found that both SO and DO neurons have a PSH with different durations. Statistical analysis showed that most SO neurons had a longer PSH duration than DO neurons (p<0.01). These data suggested that the PSH directly participated in the formation of SO and DO neurons, and the PSH elicited by the CF component was the main synaptic mechanism underlying the SO and DO response patterns. The possible biological significance of these findings relevant to bat echolocation is discussed. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. Gating of the vertex somatosensory and auditory evoked potential P50 and the correlation to skin conductance orienting response in healthy men

    DEFF Research Database (Denmark)

    Arnfred, S M; Eder, D N; Hemmingsen, R P

    2001-01-01

    A defect in auditory evoked potential (AEP) P50 gating supports the theory of information-processing deficits in schizophrenia. The relationship between gating of the mid-latency evoked potentials (EP) in the somatosensory and the auditory modalities has not been studied together before. In schiz...

  16. Development and regulation of response properties in spinal cord motoneurons

    DEFF Research Database (Denmark)

    Perrier, J F; Hounsgaard, J

    2000-01-01

    The intrinsic response properties of spinal motoneurons determine how converging premotor neuronal input is translated into the final motor command transmitted to muscles. From the patchy data available it seems that these properties and their underlying currents are highly conserved in terrestrial...... vertebrates in terms of both phylogeny and ontogeny. Spinal motoneurons in adults are remarkably similar in many respects ranging from the resting membrane potential to pacemaker properties. Apart from the axolotls, spinal motoneurons from all species investigated have latent intrinsic response properties...... mediated by L-type Ca2+ channels. This mature phenotype is reached gradually during development through phases in which A-type potassium channels and T-type calcium channels are transiently expressed. The intrinsic response properties of mature spinal motoneurons are subject to short-term adjustments via...

  17. The sensory channel of presentation alters subjective ratings and autonomic responses towards disgusting stimuli -Blood pressure, heart rate and skin conductance in response to visual, auditory, haptic and olfactory presented disgusting stimuli-

    Directory of Open Access Journals (Sweden)

    Ilona eCroy

    2013-09-01

    Full Text Available Disgust causes specific reaction patterns, observable in mimic responses and body reactions. Most research on disgust deals with visual stimuli. However, pictures may cause another disgust experience than sounds, odors or tactile stimuli. Therefore disgust experience evoked by four different sensory channels was compared.A total of 119 participants received 3 different disgusting and one control stimulus, each presented through the visual, auditory, tactile and olfactory channel. Ratings of evoked disgust as well as responses of the autonomic nervous system (heart rate, skin conductance level, systolic blood pressure were recorded and the effect of stimulus labeling and of repeated presentation was analyzed. Ratings suggested that disgust could be evoked through all senses; they were highest for visual stimuli. However, autonomic reaction towards disgusting stimuli differed according to the channel of presentation. In contrast to the other, olfactory disgust stimuli provoked a strong decrease of systolic blood pressure. Additionally, labeling enhanced disgust ratings and autonomic reaction for olfactory and tactile, but not for visual and auditory stimuli. Repeated presentation indicated that participant’s disgust rating diminishes to all but olfactory disgust stimuli. Taken together we argue that the sensory channel through which a disgust reaction is evoked matters.

  18. Modulation of Long-term Potentiation of Cortico-amygdala Synaptic Responses and Auditory Fear Memory by Dietary Polyunsaturated Fatty Acid

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    Daisuke Yamada

    2016-08-01

    Full Text Available Converging evidence suggests that an imbalance of ω3 to ω6 polyunsaturated fatty acid (PUFA in the brain is involved in mental illnesses such as anxiety disorders. However, the underlying mechanism is unknown. We previously reported that the dietary ratio of ω3 to ω6 PUFA alters this ratio in the brain, and influences contextual fear memory. In addition to behavioral change, enhancement of cannabinoid CB1 receptor-mediated short-term synaptic plasticity and facilitation of the agonist sensitivity of CB1 receptors have been observed in excitatory synaptic responses in the basolateral nucleus of the amygdala. However, it is not known whether long-term synaptic plasticity in the amygdala is influenced by the dietary ratio of ω3 to ω6 PUFA. In the present study, we examined long-term potentiation (LTP of optogenetically–evoked excitatory synaptic responses in synapses between the terminal of the projection from the auditory cortex and the pyramidal cells in the lateral nucleus of the amygdala. We found that LTP in this pathway was attenuated in mice fed a diet with a high ω3 to ω6 PUFA ratio (0.97, compared with mice fed a diet with a low ω3 to ω6 PUFA ratio (0.14. Furthermore, mice in the former condition showed reduced fear responses in an auditory fear conditioning test, compared with mice in the latter condition. In both electrophysiological and behavioral experiments, the effect of a diet with a high ω3 to ω6 PUFA ratio was completely blocked by treatment with a CB1 receptor antagonist. Furthermore, a significant reduction was observed in cholesterol content, but not in the level of an endogenous CB1 receptor agonist, 2-arachidonoylglycerol, in brain samples containing the amygdala. These results suggest that the balance of ω3 to ω6 PUFA has an impact on fear memory and cortico-amygdala synaptic plasticity, both in a CB1 receptor–dependent manner.

  19. Socially responsible intellectual property: a solution?

    Directory of Open Access Journals (Sweden)

    Abbe E. L. Brown

    2005-12-01

    Full Text Available This article reviews the extent to which the present global IP system contains an inherent imbalance between the rights of IP owning corporations and IP users, and the public benefit. It also studies the potential relevance of human rights in redressing any imbalance within existing institutional and legal fora. The article focuses on the relevance of corporate social responsibility (“CSR” related concepts, particularly in conjunction with legal human rights based arguments, to redress any imbalance by tempering the global conduct of IP owning corporations; how this new approach could be enforced, if at all, and the resulting lessons for IP and its future.

  20. Development and regulation of response properties in spinal cord motoneurons

    DEFF Research Database (Denmark)

    Perrier, J F; Hounsgaard, J

    2000-01-01

    vertebrates in terms of both phylogeny and ontogeny. Spinal motoneurons in adults are remarkably similar in many respects ranging from the resting membrane potential to pacemaker properties. Apart from the axolotls, spinal motoneurons from all species investigated have latent intrinsic response properties...

  1. 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...

  2. Transient and steady-state auditory gamma-band responses in first-degree relatives of people with autism spectrum disorder

    Directory of Open Access Journals (Sweden)

    Rojas Donald C

    2011-07-01

    Full Text Available Abstract Background Stimulus-related γ-band oscillations, which may be related to perceptual binding, are reduced in people with autism spectrum disorders (ASD. The purpose of this study was to examine auditory transient and steady-state γ-band findings in first-degree relatives of people with ASD to assess the potential familiality of these findings in ASD. Methods Magnetoencephalography (MEG recordings in 21 parents who had a child with an autism spectrum disorder (pASD and 20 healthy adult control subjects (HC were obtained. Gamma-band phase locking factor (PLF, and evoked and induced power to 32, 40 and 48 Hz amplitude-modulated sounds were measured for transient and steady-state responses. Participants were also tested on a number of behavioral and cognitive assessments related to the broad autism phenotype (BAP. Results Reliable group differences were seen primarily for steady-state responses. In the left hemisphere, pASD subjects exhibited lower phase-locked steady-state power in all three conditions. Total γ-band power, including the non-phase-locked component, was also reduced in the pASD group. In addition, pASD subjects had significantly lower PLF than the HC group. Correlations were seen between MEG measures and BAP measures. Conclusions The reduction in steady-state γ-band responses in the pASD group is consistent with previous results for children with ASD. Steady-state responses may be more sensitive than transient responses to phase-locking errors in ASD. Together with the lower PLF and phase-locked power in first-degree relatives, correlations between γ-band measures and behavioral measures relevant to the BAP highlight the potential of γ-band deficits as a potential new autism endophenotype.

  3. Spatial auditory attention is modulated by tactile priming.

    Science.gov (United States)

    Menning, Hans; Ackermann, Hermann; Hertrich, Ingo; Mathiak, Klaus

    2005-07-01

    Previous studies have shown that cross-modal processing affects perception at a variety of neuronal levels. In this study, event-related brain responses were recorded via whole-head magnetoencephalography (MEG). Spatial auditory attention was directed via tactile pre-cues (primes) to one of four locations in the peripersonal space (left and right hand versus face). Auditory stimuli were white noise bursts, convoluted with head-related transfer functions, which ensured spatial perception of the four locations. Tactile primes (200-300 ms prior to acoustic onset) were applied randomly to one of these locations. Attentional load was controlled by three different visual distraction tasks. The auditory P50m (about 50 ms after stimulus onset) showed a significant "proximity" effect (larger responses to face stimulation as well as a "contralaterality" effect between side of stimulation and hemisphere). The tactile primes essentially reduced both the P50m and N100m components. However, facial tactile pre-stimulation yielded an enhanced ipsilateral N100m. These results show that earlier responses are mainly governed by exogenous stimulus properties whereas cross-sensory interaction is spatially selective at a later (endogenous) processing stage.

  4. Auditory brainstem response as a diagnostic tool for patients suffering from schizophrenia, attention deficit hyperactivity disorder, and bipolar disorder: protocol.

    Science.gov (United States)

    Wahlström, Viktor; Åhlander, Fredrik; Wynn, Rolf

    2015-02-12

    Psychiatric disorders, such as schizophrenia, attention deficit hyperactivity disorder (ADHD), and bipolar disorder, may sometimes be difficult to diagnose. There is a great need for a valid and reliable diagnostic tool to aid clinicians in arriving at the diagnoses in a timely and accurate manner. Prior studies have suggested that patients suffering from schizophrenia and ADHD may process certain sound stimuli in the brainstem in an unusual manner. When these patient groups have been examined with the electrophysiological method of brainstem audiometry, some studies have found illness-specific aberrations. Such aberrations may also exist for patients suffering from bipolar disorder. In this study, we will examine whether the method of brainstem audiometry can be used as a diagnostic tool for patients suffering from schizophrenia, ADHD, and bipolar disorder. The method includes three steps: (1) auditory stimulation with specific sound stimuli, (2) simultaneous measurement of brainstem activity, and (3) automated interpretation of the resulting brain stem audiograms with data-based signal analysis. We will compare three groups of 12 individuals with confirmed diagnoses of schizophrenia, ADHD, or bipolar disorder with 12 healthy subjects under blinded conditions for a total of 48 participants. The extent to which the method can be used to reach the correct diagnosis will be investigated. The project is now in a recruiting phase. When all patients and controls have been recruited and the measurements have been performed, the data will be analyzed according to a previously arranged algorithm. We expect the recruiting phase and measurements to be completed in early 2015, the analyses to be performed in mid-2015, and the results of the study to be published in early 2016. If the results support previous findings, this will lend strength to the idea that brainstem audiometry can offer objective diagnostic support for patients suffering from schizophrenia, ADHD, and

  5. Event-related potentials to visual, auditory, and bimodal (combined auditory-visual) stimuli.

    Science.gov (United States)

    Isoğlu-Alkaç, Ummühan; Kedzior, Karina; Keskindemirci, Gonca; Ermutlu, Numan; Karamursel, Sacit

    2007-02-01

    The purpose of this study was to investigate the response properties of event related potentials to unimodal and bimodal stimulations. The amplitudes of N1 and P2 were larger during bimodal evoked potentials (BEPs) than auditory evoked potentials (AEPs) in the anterior sites and the amplitudes of P1 were larger during BEPs than VEPs especially at the parieto-occipital locations. Responses to bimodal stimulation had longer latencies than responses to unimodal stimulation. The N1 and P2 components were larger in amplitude and longer in latency during the bimodal paradigm and predominantly occurred at the anterior sites. Therefore, the current bimodal paradigm can be used to investigate the involvement and location of specific neural generators that contribute to higher processing of sensory information. Moreover, this paradigm may be a useful tool to investigate the level of sensory dysfunctions in clinical samples.

  6. A Brain System for Auditory Working Memory.

    Science.gov (United States)

    Kumar, Sukhbinder; Joseph, Sabine; Gander, Phillip E; Barascud, Nicolas; Halpern, Andrea R; Griffiths, Timothy D

    2016-04-20

    The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. The data support a system for auditory working memory based on the maintenance of sound-specific representations in auditory cortex by projections from higher-order areas, including the hippocampus and frontal cortex. In this work, we demonstrate a system for maintaining sound in working memory based on activity in auditory cortex, hippocampus, and frontal cortex, and functional connectivity among them. Specifically, our work makes three advances from the previous work. First, we robustly demonstrate hippocampal involvement in all phases of auditory working memory (encoding, maintenance, and retrieval): the role of hippocampus in working memory is controversial. Second, using a pattern classification technique, we show that activity in the auditory cortex and inferior frontal gyrus is specific to the maintained tones in working memory. Third, we show long-range connectivity of auditory cortex to hippocampus and frontal cortex, which may be responsible for keeping such representations active during working memory maintenance. Copyright © 2016 Kumar et al.

  7. Dynamics of auditory working memory

    Directory of Open Access Journals (Sweden)

    Jochen eKaiser

    2015-05-01

    Full Text Available Working memory denotes the ability to retain stimuli in mind that are no longer physically present and to perform mental operations on them. Electro- and magnetoencephalography allow investigating the short-term maintenance of acoustic stimuli at a high temporal resolution. Studies investigating working memory for non-spatial and spatial auditory information have suggested differential roles of regions along the putative auditory ventral and dorsal streams, respectively, in the processing of the different sound properties. Analyses of event-related potentials have shown sustained, memory load-dependent deflections over the retention periods. The topography of these waves suggested an involvement of modality-specific sensory storage regions. Spectral analysis has yielded information about the temporal dynamics of auditory working memory processing of individual stimuli, showing activation peaks during the delay phase whose timing was related to task performance. Coherence at different frequencies was enhanced between frontal and sensory cortex. In summary, auditory working memory seems to rely on the dynamic interplay between frontal executive systems and sensory representation regions.

  8. Sparse representation of sounds in the unanesthetized auditory cortex.

    Directory of Open Access Journals (Sweden)

    Tomás Hromádka

    2008-01-01

    Full Text Available How do neuronal populations in the auditory cortex represent acoustic stimuli? Although sound-evoked neural responses in the anesthetized auditory cortex are mainly transient, recent experiments in the unanesthetized preparation have emphasized subpopulations with other response properties. To quantify the relative contributions of these different subpopulations in the awake preparation, we have estimated the representation of sounds across the neuronal population using a representative ensemble of stimuli. We used cell-attached recording with a glass electrode, a method for which single-unit isolation does not depend on neuronal activity, to quantify the fraction of neurons engaged by acoustic stimuli (tones, frequency modulated sweeps, white-noise bursts, and natural stimuli in the primary auditory cortex of awake head-fixed rats. We find that the population response is sparse, with stimuli typically eliciting high firing rates (>20 spikes/second in less than 5% of neurons at any instant. Some neurons had very low spontaneous firing rates (<0.01 spikes/second. At the other extreme, some neurons had driven rates in excess of 50 spikes/second. Interestingly, the overall population response was well described by a lognormal distribution, rather than the exponential distribution that is often reported. Our results represent, to our knowledge, the first quantitative evidence for sparse representations of sounds in the unanesthetized auditory cortex. Our results are compatible with a model in which most neurons are silent much of the time, and in which representations are composed of small dynamic subsets of highly active neurons.

  9. The non-lemniscal auditory cortex in ferrets: convergence of corticotectal inputs in the superior colliculus

    Directory of Open Access Journals (Sweden)

    Victoria M Bajo

    2010-05-01

    Full Text Available Descending cortical inputs to the superior colliculus (SC contribute to the unisensory response properties of the neurons found there and are critical for multisensory integration. However, little is known about the relative contribution of different auditory cortical areas to this projection or the distribution of their terminals in the SC. We characterized this projection in the ferret by injecting tracers in the SC and auditory cortex. Large pyramidal neurons were labeled in layer V of different parts of the ectosylvian gyrus after tracer injections in the SC. Those cells were most numerous in the anterior ectosylvian gyrus (AEG, and particularly in the anterior ventral field, which receives both auditory and visual inputs. Labeling was also found in the posterior ectosylvian gyrus (PEG, predominantly in the tonotopically-organized posterior suprasylvian field. Profuse anterograde labeling was present in the SC following tracer injections at the site of acoustically-responsive neurons in the AEG or PEG, with terminal fields being both more prominent and clustered for inputs originating from the AEG. Terminals from both cortical areas were located throughout the intermediate and deep layers, but were most concentrated in the posterior half of the SC, where peripheral stimulus locations are represented. No inputs were identified from primary auditory cortical areas, although some labeling was found in the surrounding sulci. Our findings suggest that higher level auditory cortical areas, including those involved in multisensory processing, may modulate SC function via their projections into its deeper layers.

  10. Detection of stimulus deviance within primate primary auditory cortex: intracortical mechanisms of mismatch negativity (MMN) generation.

    Science.gov (United States)

    Javitt, D C; Steinschneider, M; Schroeder, C E; Vaughan, H G; Arezzo, J C

    1994-12-26

    Mismatch negativity (MMN) is a cognitive, auditory event-related potential (AEP) that reflects preattentive detection of stimulus deviance and indexes the operation of the auditory sensory ('echoic') memory system. MMN is elicited most commonly in an auditory oddball paradigm in which a sequence of repetitive standard stimuli is interrupted infrequently and unexpectedly by a physically deviant 'oddball' stimulus. Electro- and magnetoencephalographic dipole mapping studies have localized the generators of MMN to supratemporal auditory cortex in the vicinity of Heschl's gyrus, but have not determined the degree to which MMN reflects activation within primary auditory cortex (AI) itself. The present study, using moveable multichannel electrodes inserted acutely into superior temporal plane, demonstrates a significant contribution of AI to scalp-recorded MMN in the monkey, as reflected by greater response of AI to loud or soft clicks presented as deviants than to the same stimuli presented as repetitive standards. The MMN-like activity was localized primarily to supragranular laminae within AI. Thus, standard and deviant stimuli elicited similar degrees of initial, thalamocortical excitation. In contrast, responses within supragranular cortex were significantly larger to deviant stimuli than to standards. No MMN-like activity was detected in a limited number to passes that penetrated anterior and medial to AI. AI plays a well established role in the decoding of the acoustic properties of individual stimuli. The present study demonstrates that primary auditory cortex also plays an important role in processing the relationships between stimuli, and thus participates in cognitive, as well as purely sensory, processing of auditory information.

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

    Science.gov (United States)

    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.

  12. Molecular approach of auditory neuropathy.

    Science.gov (United States)

    Silva, Magali Aparecida Orate Menezes da; Piatto, Vânia Belintani; Maniglia, Jose Victor

    2015-01-01

    Mutations in the otoferlin gene are responsible for auditory neuropathy. To investigate the prevalence of mutations in the mutations in the otoferlin gene in patients with and without auditory neuropathy. This original cross-sectional case study evaluated 16 index cases with auditory neuropathy, 13 patients with sensorineural hearing loss, and 20 normal-hearing subjects. DNA was extracted from peripheral blood leukocytes, and the mutations in the otoferlin gene sites were amplified by polymerase chain reaction/restriction fragment length polymorphism. The 16 index cases included nine (56%) females and seven (44%) males. The 13 deaf patients comprised seven (54%) males and six (46%) females. Among the 20 normal-hearing subjects, 13 (65%) were males and seven were (35%) females. Thirteen (81%) index cases had wild-type genotype (AA) and three (19%) had the heterozygous AG genotype for IVS8-2A-G (intron 8) mutation. The 5473C-G (exon 44) mutation was found in a heterozygous state (CG) in seven (44%) index cases and nine (56%) had the wild-type allele (CC). Of these mutants, two (25%) were compound heterozygotes for the mutations found in intron 8 and exon 44. All patients with sensorineural hearing loss and normal-hearing individuals did not have mutations (100%). There are differences at the molecular level in patients with and without auditory neuropathy. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  13. Aging effects on the binaural interaction component of the auditory brainstem response in the Mongolian gerbil: Effects of interaural time and level differences.

    Science.gov (United States)

    Laumen, Geneviève; Tollin, Daniel J; Beutelmann, Rainer; Klump, Georg M

    2016-07-01

    The effect of interaural time difference (ITD) and interaural level difference (ILD) on wave 4 of the binaural and summed monaural auditory brainstem responses (ABRs) as well as on the DN1 component of the binaural interaction component (BIC) of the ABR in young and old Mongolian gerbils (Meriones unguiculatus) was investigated. Measurements were made at a fixed sound pressure level (SPL) and a fixed level above visually detected ABR threshold to compensate for individual hearing threshold differences. In both stimulation modes (fixed SPL and fixed level above visually detected ABR threshold) an effect of ITD on the latency and the amplitude of wave 4 as well as of the BIC was observed. With increasing absolute ITD values BIC latencies were increased and amplitudes were decreased. ILD had a much smaller effect on these measures. Old animals showed a reduced amplitude of the DN1 component. This difference was due to a smaller wave 4 in the summed monaural ABRs of old animals compared to young animals whereas wave 4 in the binaural-evoked ABR showed no age-related difference. In old animals the small amplitude of the DN1 component was correlated with small binaural-evoked wave 1 and wave 3 amplitudes. This suggests that the reduced peripheral input affects central binaural processing which is reflected in the BIC. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Cortical perfusion response to an electrical stimulation of the auditory nerve in profoundly deaf patients: Study with technetium-99m hexamethylpropylene amine oxime single photon emission tomography

    International Nuclear Information System (INIS)

    Le Scao, Y.; Robier, A.; Beuter, P.; Baulieu, J.L.; Pourcelot, L.

    1992-01-01

    Brain activation procedures associated with single photon emission tomography (SPET) have recently been developed in healthy controls and diseased patients in order to help in their diagnosis and treatment. We investigated the effects of a promontory test (PT) on the cerebral distribution of technetium-99m hexamethyl-propylene amine oxime ( 99m Tc-HMPAO) in 7 profoundly deaf patients, 6 PT+ and PT-. The count variation in the temporal lobe was calculated on 6 coronal slices using the ratio (R stimulation -R deprivation )/R deprivation where R=counts in the temporal lobe was observed in all patients and was higher in all patients with PT+ than in the patient with PT-. The problems of head positioning and resolution of the system were taken into account, and we considered that the maximal count increment was related to the auditory cortex response to the stimulus. Further clinical investigations with high-resolution systems have to be performed in order to validate this presurgery test in cochlear implant assessment. (orig.)

  15. Cortical perfusion response to an electrical stimulation of the auditory nerve in profoundly deaf patients: Study with technetium-99m hexamethylpropylene amine oxime single photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Le Scao, Y.; Robier, A.; Beuter, P. (Centre Hospitalier Universitaire, 37 - Tours (France). Dept. of Otorhinolaryngology); Baulieu, J.L.; Pourcelot, L. (Centre Hospitalier Universitaire, 37 - Tours (France). Dept. of Nuclear Medicine)

    1992-04-01

    Brain activation procedures associated with single photon emission tomography (SPET) have recently been developed in healthy controls and diseased patients in order to help in their diagnosis and treatment. We investigated the effects of a promontory test (PT) on the cerebral distribution of technetium-99m hexamethyl-propylene amine oxime ({sup 99m}Tc-HMPAO) in 7 profoundly deaf patients, 6 PT+ and PT-. The count variation in the temporal lobe was calculated on 6 coronal slices using the ratio (R{sub stimulation}-R{sub deprivation})/R{sub deprivation} where R=counts in the temporal lobe was observed in all patients and was higher in all patients with PT+ than in the patient with PT-. The problems of head positioning and resolution of the system were taken into account, and we considered that the maximal count increment was related to the auditory cortex response to the stimulus. Further clinical investigations with high-resolution systems have to be performed in order to validate this presurgery test in cochlear implant assessment. (orig.).

  16. Cortical perfusion response to an electrical stimulation of the auditory nerve in profoundly deaf patients: study with technetium-99m hexamethylpropylene amine oxime single photon emission tomography.

    Science.gov (United States)

    Le Scao, Y; Robier, A; Baulieu, J L; Beutter, P; Pourcelot, L

    1992-01-01

    Brain activation procedures associated with single photon emission tomography (SPET) have recently been developed in healthy controls and diseased patients in order to help in their diagnosis and treatment. We investigated the effects of a promontory test (PT) on the cerebral distribution of technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) in 7 profoundly deaf patients, 6 PT+ and one PT-. The count variation in the temporal lobe was calculated on 6 coronal slices using the ratio (Rstimulation-Rdeprivation)/Rdeprivation where R = counts in the temporal lobe/whole-brain count. A count increase in the temporal lobe was observed in all patients and was higher in all patients with PT+ than in the patient with PT-. The problems of head positioning and resolution of the system were taken into account, and we considered that the maximal count increment was related to the auditory cortex response to the stimulus. Further clinical investigations with high-resolution systems have to be performed in order to validate this presurgery test in cochlear implant assessment.

  17. Auditory-vocal mirroring in songbirds.

    Science.gov (United States)

    Mooney, Richard

    2014-01-01

    Mirror neurons are theorized to serve as a neural substrate for spoken language in humans, but the existence and functions of auditory-vocal mirror neurons in the human brain remain largely matters of speculation. Songbirds resemble humans in their capacity for vocal learning and depend on their learned songs to facilitate courtship and individual recognition. Recent neurophysiological studies have detected putative auditory-vocal mirror neurons in a sensorimotor region of the songbird's brain that plays an important role in expressive and receptive aspects of vocal communication. This review discusses the auditory and motor-related properties of these cells, considers their potential role on song learning and communication in relation to classical studies of birdsong, and points to the circuit and developmental mechanisms that may give rise to auditory-vocal mirroring in the songbird's brain.

  18. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    DEFF Research Database (Denmark)

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders

    2016-01-01

    Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS...

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

    Science.gov (United States)

    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

  20. Auditory Processing Disorder (For Parents)

    Science.gov (United States)

    ... role. Auditory cohesion problems: This is when higher-level listening tasks are difficult. Auditory cohesion skills — drawing inferences from conversations, understanding riddles, or comprehending verbal math problems — require heightened auditory processing and language levels. ...

  1. Trading of dynamic interaural time and level difference cues and its effect on the auditory motion-onset response measured with electroencephalography.

    Science.gov (United States)

    Altmann, Christian F; Ueda, Ryuhei; Bucher, Benoit; Furukawa, Shigeto; Ono, Kentaro; Kashino, Makio; Mima, Tatsuya; Fukuyama, Hidenao

    2017-10-01

    Interaural time (ITD) and level differences (ILD) constitute the two main cues for sound localization in the horizontal plane. Despite extensive research in animal models and humans, the mechanism of how these two cues are integrated into a unified percept is still far from clear. In this study, our aim was to test with human electroencephalography (EEG) whether integration of dynamic ITD and ILD cues is reflected in the so-called motion-onset response (MOR), an evoked potential elicited by moving sound sources. To this end, ITD and ILD trajectories were determined individually by cue trading psychophysics. We then measured EEG while subjects were presented with either static click-trains or click-trains that contained a dynamic portion at the end. The dynamic part was created by combining ITD with ILD either congruently to elicit the percept of a right/leftward moving sound, or incongruently to elicit the percept of a static sound. In two experiments that differed in the method to derive individual dynamic cue trading stimuli, we observed an MOR with at least a change-N1 (cN1) component for both the congruent and incongruent conditions at about 160-190 ms after motion-onset. A significant change-P2 (cP2) component for both the congruent and incongruent ITD/ILD combination was found only in the second experiment peaking at about 250 ms after motion onset. In sum, this study shows that a sound which - by a combination of counter-balanced ITD and ILD cues - induces a static percept can still elicit a motion-onset response, indicative of independent ITD and ILD processing at the level of the MOR - a component that has been proposed to be, at least partly, generated in non-primary auditory cortex. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Auditory-motor interaction revealed by fMRI: speech, music, and working memory in area Spt.

    Science.gov (United States)

    Hickok, Gregory; Buchsbaum, Bradley; Humphries, Colin; Muftuler, Tugan

    2003-07-01

    The concept of auditory-motor interaction pervades speech science research, yet the cortical systems supporting this interface have not been elucidated. Drawing on experimental designs used in recent work in sensory-motor integration in the cortical visual system, we used fMRI in an effort to identify human auditory regions with both sensory and motor response properties, analogous to single-unit responses in known visuomotor integration areas. The sensory phase of the task involved listening to speech (nonsense sentences) or music (novel piano melodies); the "motor" phase of the task involved covert rehearsal/humming of the auditory stimuli. A small set of areas in the superior temporal and temporal-parietal cortex responded both during the listening phase and the rehearsal/humming phase. A left lateralized region in the posterior Sylvian fissure at the parietal-temporal boundary, area Spt, showed particularly robust responses to both phases of the task. Frontal areas also showed combined auditory + rehearsal responsivity consistent with the claim that the posterior activations are part of a larger auditory-motor integration circuit. We hypothesize that this circuit plays an important role in speech development as part of the network that enables acoustic-phonetic input to guide the acquisition of language-specific articulatory-phonetic gestures; this circuit may play a role in analogous musical abilities. In the adult, this system continues to support aspects of speech production, and, we suggest, supports verbal working memory.

  3. Floor response spectra of buildings with uncertain structural properties

    International Nuclear Information System (INIS)

    Chen, P.C.

    1975-01-01

    All Category I equipment, such as reactors, vessels, and major piping systems of nuclear power plants, is required to withstand earthquake loadings in order to minimize risk of seismic damage. The equipment is designed by using response spectra of the floor on which the equipment is mounted. The floor response spectra are constructed usually from the floor response time histories which are obtained through a deterministic dynamic analysis. This analysis assumes that all structural parameters, such as mass, stiffness, and damping have been calculated precisely, and that the earthquakes are known. However, structural parameters are usually difficult to determine precisely if the structures are massive and/or irregular, such as nuclear containments and its internal structures with foundation soil incorporated into the analysis. Faced with these uncertainties, it has been the practice to broaden the floor response spectra peaks by +-10 percent of the peak frequencies on the basis of conservatism. This approach is based on engineering judgement and does not have an analytical basis to provide a sufficient level of confidence in using these spectra for equipment design. To insure reliable design, it is necessary to know structural response variations due to variations in structural properties. This consideration leads to the treatment of structural properties as random variables and the use of probabilistic methods to predict structural response more accurately. New results on floor response spectra of buildings with uncertain structural properties obtained by determining the probabilistic dynamic response from the deterministic dynamic response and its standard deviation are presented. The resulting probabilistic floor response spectra are compared with those obtained deterministically, and are shown to provide a more reliable method for determining seismic forces

  4. The Role of Auditory Evoked Potentials in the Context of Cochlear Implant Provision.

    Science.gov (United States)

    Hoth, Sebastian; Dziemba, Oliver Christian

    2017-12-01

    : Auditory evoked potentials (AEP) are highly demanded during the whole process of equipping patients with cochlear implants (CI). They play an essential role in preoperative diagnostics, intraoperative testing, and postoperative monitoring of auditory performance and success. The versatility of AEP's is essentially enhanced by their property to be evokable by acoustic as well as electric stimuli. Thus, the electric responses of the auditory system following acoustic stimulation and recorded by the conventional surface technique as well as by transtympanic derivation from the promontory (Electrocochleography [ECochG]) are used for the quantitative determination of hearing loss and, additionally, electrically evoked compound actions potentials (ECAP) can be recorded with the intracochlear electrodes of the implant just adjacent to the stimulation electrode to check the functional integrity of the device and its coupling to the auditory system. The profile of ECAP thresholds is used as basis for speech processor fitting, the spread of excitation (SOE) allows the identification of electrode mislocations such as array foldover, and recovery functions may serve to optimize stimulus pulse rate. These techniques as well as those relying on scalp surface activity originating in the brainstem or the auditory cortex accompany the CI recipient during its whole life span and they offer valuable insights into functioning and possible adverse effects of the CI for clinical and scientific purposes.

  5. Sex differences in the refractory period of the 100 ms auditory evoked magnetic field.

    Science.gov (United States)

    Rojas, D C; Teale, P; Sheeder, J; Reite, M

    1999-11-08

    The 100 ms latency auditory evoked magnetic response (M100) has been implicated in the earliest stage of acoustic memory encoding in the brain. Sex differences in this response have been found in its location within the brain and its functional properties. We recorded the M100 in 25 adults in response to changes in interstimulus interval of an auditory stimulus. Response amplitudes of the M100 were used to compute a measure of the M100 refractory period, which has been proposed to index the decay time constant of echoic memory. This time constant was significantly longer in both hemispheres of the female participants when compared to the male participants. Possible implications of this for behavioral sex differences in human memory performance are discussed.

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

    Science.gov (United States)

    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.

  7. Early postnatal virus inoculation into the scala media achieved extensive expression of exogenous green fluorescent protein in the inner ear and preserved auditory brainstem response thresholds.

    Science.gov (United States)

    Wang, Yunfeng; Sun, Yu; Chang, Qing; Ahmad, Shoeb; Zhou, Binfei; Kim, Yeunjung; Li, Huawei; Lin, Xi

    2013-01-01

    Gene transfer into the inner ear is a promising approach for treating sensorineural hearing loss. The special electrochemical environment of the scala media raises a formidable challenge for effective gene delivery at the same time as keeping normal cochlear function intact. The present study aimed to define a suitable strategy for preserving hearing after viral inoculation directly into the scala media performed at various postnatal developmental stages. We assessed transgene expression of green fluorescent protein (GFP) mediated by various types of adeno-associated virus (AAV) and lentivirus (LV) in the mouse cochlea. Auditory brainstem responses were measured 30 days after inoculation to assess effects on hearing. Patterns of GFP expression confirmed extensive exogenous gene expression in various types of cells lining the endolymphatic space. The use of different viral vectors and promoters resulted in specific cellular GFP expression patterns. AAV2/1 with cytomegalovirus promoter apparently gave the best results for GFP expression in the supporting cells. Histological examination showed normal cochlear morphology and no hair cell loss after either AAV or LV injections. We found that hearing thresholds were not significantly changed when the injections were performed in mice younger than postnatal day 5, regardless of the type of virus tested. Viral inoculation and expression in the inner ear for the restoration of hearing must not damage cochlear function. Using normal hearing mice as a model, we have achieved this necessary step, which is required for the treatment of many types of congenital deafness that require early intervention. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Auditory Brainstem Responses to Bone-Conducted Brief Tones in Young Children with Conductive or Sensorineural Hearing Loss

    Directory of Open Access Journals (Sweden)

    Jennifer L. Hatton

    2012-01-01

    Full Text Available The bone-conduction (BC tone ABR has been used clinically for over 20 years. The current study formally evaluated the test performance of the BC tone-evoked ABR in infants with hearing loss. Method. By comparing BC-ABR results to follow-up behavioural results, this study addressed two questions: (i whether the BC tone ABR was successful in differentiating children with conductive versus sensorineural hearing loss (Study A; conductive: 68 ears; SNHL: 129 ears and (ii the relationship between BC ABR and behavioural hearing loss severity (Study B: 2000 Hz: 104 ears; 500 Hz: 47 ears. Results. Results demonstrate that the “normal” BC-ABR levels accurately differentiated normal versus elevated cochlear sensitivity (accuracy: 98% for 2000 Hz; 98% for 500 Hz. A subset of infants in Study A with elevated BC-ABR (i.e., no response at normal level had additional testing at higher intensities, which allowed for categorization of the degree of cochlear impairment. Study B results indicate that the BC ABR accurately categorizes the degree of cochlear hearing loss for 2000 Hz (accuracy = 95.2%. A preliminary dBnHL-to-dBHL correction factor of “0 dB” was determined for 2000 Hz BC ABR. Conclusions. These findings further support the use of BC tone ABR for diagnostic ABR testing.

  9. Auditory Brainstem Responses to Bone-Conducted Brief Tones in Young Children with Conductive or Sensorineural Hearing Loss

    Science.gov (United States)

    Hatton, Jennifer L.; Janssen, Renée M.; Stapells, David R.

    2012-01-01

    The bone-conduction (BC) tone ABR has been used clinically for over 20 years. The current study formally evaluated the test performance of the BC tone-evoked ABR in infants with hearing loss. Method. By comparing BC-ABR results to follow-up behavioural results, this study addressed two questions: (i) whether the BC tone ABR was successful in differentiating children with conductive versus sensorineural hearing loss (Study A; conductive: 68 ears; SNHL: 129 ears) and (ii) the relationship between BC ABR and behavioural hearing loss severity (Study B: 2000 Hz: 104 ears; 500 Hz: 47 ears). Results. Results demonstrate that the “normal” BC-ABR levels accurately differentiated normal versus elevated cochlear sensitivity (accuracy: 98% for 2000 Hz; 98% for 500 Hz). A subset of infants in Study A with elevated BC-ABR (i.e., no response at normal level) had additional testing at higher intensities, which allowed for categorization of the degree of cochlear impairment. Study B results indicate that the BC ABR accurately categorizes the degree of cochlear hearing loss for 2000 Hz (accuracy = 95.2%). A preliminary dBnHL-to-dBHL correction factor of “0 dB” was determined for 2000 Hz BC ABR. Conclusions. These findings further support the use of BC tone ABR for diagnostic ABR testing. PMID:22988461

  10. Auditory-motor learning influences auditory memory for music.

    Science.gov (United States)

    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.

  11. Neuronal Correlates of Auditory Streaming in Monkey Auditory Cortex for Tone Sequences without Spectral Differences

    Directory of Open Access Journals (Sweden)

    Stanislava Knyazeva

    2018-01-01

    Full Text Available This study finds a neuronal correlate of auditory perceptual streaming in the primary auditory cortex for sequences of tone complexes that have the same amplitude spectrum but a different phase spectrum. Our finding is based on microelectrode recordings of multiunit activity from 270 cortical sites in three awake macaque monkeys. The monkeys were presented with repeated sequences of a tone triplet that consisted of an A tone, a B tone, another A tone and then a pause. The A and B tones were composed of unresolved harmonics formed by adding the harmonics in cosine phase, in alternating phase, or in random phase. A previous psychophysical study on humans revealed that when the A and B tones are similar, humans integrate them into a single auditory stream; when the A and B tones are dissimilar, humans segregate them into separate auditory streams. We found that the similarity of neuronal rate responses to the triplets was highest when all A and B tones had cosine phase. Similarity was intermediate when the A tones had cosine phase and the B tones had alternating phase. Similarity was lowest when the A tones had cosine phase and the B tones had random phase. The present study corroborates and extends previous reports, showing similar correspondences between neuronal activity in the primary auditory cortex and auditory streaming of sound sequences. It also is consistent with Fishman’s population separation model of auditory streaming.

  12. Neuronal Correlates of Auditory Streaming in Monkey Auditory Cortex for Tone Sequences without Spectral Differences.

    Science.gov (United States)

    Knyazeva, Stanislava; Selezneva, Elena; Gorkin, Alexander; Aggelopoulos, Nikolaos C; Brosch, Michael

    2018-01-01

    This study finds a neuronal correlate of auditory perceptual streaming in the primary auditory cortex for sequences of tone complexes that have the same amplitude spectrum but a different phase spectrum. Our finding is based on microelectrode recordings of multiunit activity from 270 cortical sites in three awake macaque monkeys. The monkeys were presented with repeated sequences of a tone triplet that consisted of an A tone, a B tone, another A tone and then a pause. The A and B tones were composed of unresolved harmonics formed by adding the harmonics in cosine phase, in alternating phase, or in random phase. A previous psychophysical study on humans revealed that when the A and B tones are similar, humans integrate them into a single auditory stream; when the A and B tones are dissimilar, humans segregate them into separate auditory streams. We found that the similarity of neuronal rate responses to the triplets was highest when all A and B tones had cosine phase. Similarity was intermediate when the A tones had cosine phase and the B tones had alternating phase. Similarity was lowest when the A tones had cosine phase and the B tones had random phase. The present study corroborates and extends previous reports, showing similar correspondences between neuronal activity in the primary auditory cortex and auditory streaming of sound sequences. It also is consistent with Fishman's population separation model of auditory streaming.

  13. Auditory Integration Training

    Directory of Open Access Journals (Sweden)

    Zahra Jafari

    2002-07-01

    Full Text Available Auditory integration training (AIT is a hearing enhancement training process for sensory input anomalies found in individuals with autism, attention deficit hyperactive disorder, dyslexia, hyperactivity, learning disability, language impairments, pervasive developmental disorder, central auditory processing disorder, attention deficit disorder, depressin, and hyperacute hearing. AIT, recently introduced in the United States, and has received much notice of late following the release of The Sound of a Moracle, by Annabel Stehli. In her book, Mrs. Stehli describes before and after auditory integration training experiences with her daughter, who was diagnosed at age four as having autism.

  14. Review: Auditory Integration Training

    Directory of Open Access Journals (Sweden)

    Zahra Ja'fari

    2003-01-01

    Full Text Available Auditory integration training (AIT is a hearing enhancement training process for sensory input anomalies found in individuals with autism, attention deficit hyperactive disorder, dyslexia, hyperactivity, learning disability, language impairments, pervasive developmental disorder, central auditory processing disorder, attention deficit disorder, depression, and hyper acute hearing. AIT, recently introduced in the United States, and has received much notice of late following the release of the sound of a miracle, by Annabel Stehli. In her book, Mrs. Stehli describes before and after auditory integration training experiences with her daughter, who was diagnosed at age four as having autism.

  15. Auditory interfaces in automated driving: an international survey

    NARCIS (Netherlands)

    Bazilinskyy, P.; de Winter, J.C.F.

    2015-01-01

    This study investigated peoples’ opinion on auditory interfaces in contemporary
    cars and their willingness to be exposed to auditory feedback in automated driving. We used an Internet-based survey to collect 1,205 responses from 91 countries. The respondents stated their attitudes towards two

  16. 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.

  17. Identifying cochlear implant channels with poor electrode-neuron interface: electrically-evoked auditory brainstem responses measured with the partial tripolar configuration

    Science.gov (United States)

    Bierer, Julie Arenberg; Faulkner, Kathleen F.; Tremblay, Kelly L.

    2011-01-01

    Objectives The goal of this study was to compare cochlear implant behavioral measures and electrically-evoked auditory brainstem responses (EABRs) obtained with a spatially focused electrode configuration. It has been shown previously that channels with high thresholds, when measured with the tripolar configuration, exhibit relatively broad psychophysical tuning curves (Bierer and Faulkner, 2010). The elevated threshold and degraded spatial/spectral selectivity of such channels are consistent with a poor electrode-neuron interface, such as suboptimal electrode placement or reduced nerve survival. However, the psychophysical methods required to obtain these data are time intensive and may not be practical during a clinical mapping procedure, especially for young children. Here we have extended the previous investigation to determine if a physiological approach could provide a similar assessment of channel functionality. We hypothesized that, in accordance with the perceptual measures, higher EABR thresholds would correlate with steeper EABR amplitude growth functions, reflecting a degraded electrode-neuron interface. Design Data were collected from six cochlear implant listeners implanted with the HiRes 90k cochlear implant (Advanced Bionics). Single-channel thresholds and most comfortable listening levels were obtained for stimuli that varied in presumed electrical field size by using the partial tripolar configuration, for which a fraction of current (σ) from a center active electrode returns through two neighboring electrodes and the remainder through a distant indifferent electrode. EABRs were obtained in each subject for the two channels having the highest and lowest tripolar (σ=1 or 0.9) behavioral threshold. Evoked potentials were measured with both the monopolar (σ=0) and a more focused partial tripolar (σ ≥ 0.50) configuration. Results Consistent with previous studies, EABR thresholds were highly and positively correlated with behavioral thresholds

  18. Identifying cochlear implant channels with poor electrode-neuron interfaces: electrically evoked auditory brain stem responses measured with the partial tripolar configuration.

    Science.gov (United States)

    Bierer, Julie Arenberg; Faulkner, Kathleen F; Tremblay, Kelly L

    2011-01-01

    The goal of this study was to compare cochlear implant behavioral measures and electrically evoked auditory brain stem responses (EABRs) obtained with a spatially focused electrode configuration. It has been shown previously that channels with high thresholds, when measured with the tripolar configuration, exhibit relatively broad psychophysical tuning curves. The elevated threshold and degraded spatial/spectral selectivity of such channels are consistent with a poor electrode-neuron interface, defined as suboptimal electrode placement or reduced nerve survival. However, the psychophysical methods required to obtain these data are time intensive and may not be practical during a clinical mapping session, especially for young children. Here, we have extended the previous investigation to determine whether a physiological approach could provide a similar assessment of channel functionality. We hypothesized that, in accordance with the perceptual measures, higher EABR thresholds would correlate with steeper EABR amplitude growth functions, reflecting a degraded electrode-neuron interface. Data were collected from six cochlear implant listeners implanted with the HiRes 90k cochlear implant (Advanced Bionics). Single-channel thresholds and most comfortable listening levels were obtained for stimuli that varied in presumed electrical field size by using the partial tripolar configuration, for which a fraction of current (σ) from a center active electrode returns through two neighboring electrodes and the remainder through a distant indifferent electrode. EABRs were obtained in each subject for the two channels having the highest and lowest tripolar (σ = 1 or 0.9) behavioral threshold. Evoked potentials were measured with both the monopolar (σ = 0) and a more focused partial tripolar (σ ≥ 0.50) configuration. Consistent with previous studies, EABR thresholds were highly and positively correlated with behavioral thresholds obtained with both the monopolar and partial

  19. Predictive uncertainty in auditory sequence processing

    Directory of Open Access Journals (Sweden)

    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.

  20. Predictive uncertainty in auditory sequence processing.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  2. An evoked auditory response fMRI study of the effects of rTMS on putative AVH pathways in healthy volunteers.

    LENUS (Irish Health Repository)

    Tracy, D K

    2010-01-01

    Auditory verbal hallucinations (AVH) are the most prevalent symptom in schizophrenia. They are associated with increased activation within the temporoparietal cortices and are refractory to pharmacological and psychological treatment in approximately 25% of patients. Low frequency repetitive transcranial magnetic stimulation (rTMS) over the temporoparietal cortex has been demonstrated to be effective in reducing AVH in some patients, although results have varied. The cortical mechanism by which rTMS exerts its effects remain unknown, although data from the motor system is suggestive of a local cortical inhibitory effect. We explored neuroimaging differences in healthy volunteers between application of a clinically utilized rTMS protocol and a sham rTMS equivalent when undertaking a prosodic auditory task.

  3. Potenciais Evocados Auditivos de Média Latência: estudo em crianças saudáveis Auditory Middle Latency Responses: a study of healthy children

    Directory of Open Access Journals (Sweden)

    Ana Claudia Figueiredo Frizzo

    2007-06-01

    Full Text Available OBJETIVO: Investigar os componentes dos PEAMLs em crianças saudáveis para determinar suas propriedades. MATERIAL E MÉTODOS: 32 crianças, de ambos os sexos, 10 a 13 anos de idade, sem doenças neurológicas, participaram do estudo. Os dados foram analisados pela estatística descritiva (média e desvio padrão e por análise de variância (teste F. PEAMLs foram pesquisadas usando estímulo tom burst nas intensidades de 50, 60 e 70 dB NA. RESULTADOS E CONCLUSÃO: A média de latência dos componentes foi Na = 20.79ms, Pa = 35.34ms, Nb = 43.27ms e Pb = 53.36ms, a 70dB NA. A média dos valores de amplitude NaPa variou de 0.2 a 1.9 uV (M = 1.0 uV. A amplitude aumentou e a latência diminuiu com o aumento da intensidade sonora. A inclinação do complexo de ondas NaPa esteve presente em alguns casos, o que merece atenção em estudos semelhantes ou em mesmo em populações de crianças com dificuldade de fala e linguagem e do processamento auditivo. CONCLUSÃO: O presente trabalho trouxe informações adicionais sobre as AMLRs e pode servir como referência para outros estudos clínicos ou experimentais em crianças.AIM: To examine the components of auditory middle latency responses (AMLRs in a sample of healthy children to establish their properties. METHODS: Thirty-two children of both genders aged between 10 to 13 years, with no neurological disorders, were included in the study. Data were analyzed statistically by descriptive statistics (mean + SD and by analysis of variance using the F test. AMLRs were investigated with toneburst stimuli at 50, 60 and 70 dB HL. RESULTS AND CONCLUSIONS: The mean latencies of the components were Na = 20.79 ms, Pa = 35.34 ms, Nb = 43.27 ms, and Pb = 53.36 ms, in 70 dB HL. The mean values for the NaPa amplitude ranged from 0.2 to 1.9 mV (M = 1.0 mV. The amplitude increased and latency decreased with increasing sound intensity. Inclination of the NaPa wave complex was present in some cases, which deserves

  4. Visual cortex and auditory cortex activation in early binocularly blind macaques: A BOLD-fMRI study using auditory stimuli.

    Science.gov (United States)

    Wang, Rong; Wu, Lingjie; Tang, Zuohua; Sun, Xinghuai; Feng, Xiaoyuan; Tang, Weijun; Qian, Wen; Wang, Jie; Jin, Lixin; Zhong, Yufeng; Xiao, Zebin

    2017-04-15

    Cross-modal plasticity within the visual and auditory cortices of early binocularly blind macaques is not well studied. In this study, four healthy neonatal macaques were assigned to group A (control group) or group B (binocularly blind group). Sixteen months later, blood oxygenation level-dependent functional imaging (BOLD-fMRI) was conducted to examine the activation in the visual and auditory cortices of each macaque while being tested using pure tones as auditory stimuli. The changes in the BOLD response in the visual and auditory cortices of all macaques were compared with immunofluorescence staining findings. Compared with group A, greater BOLD activity was observed in the bilateral visual cortices of group B, and this effect was particularly obvious in the right visual cortex. In addition, more activated volumes were found in the bilateral auditory cortices of group B than of group A, especially in the right auditory cortex. These findings were consistent with the fact that there were more c-Fos-positive cells in the bilateral visual and auditory cortices of group B compared with group A (p visual cortices of binocularly blind macaques can be reorganized to process auditory stimuli after visual deprivation, and this effect is more obvious in the right than the left visual cortex. These results indicate the establishment of cross-modal plasticity within the visual and auditory cortices. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. 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

  6. 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

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

    Science.gov (United States)

    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

  8. Auditory processing in autism spectrum disorder

    DEFF Research Database (Denmark)

    Vlaskamp, Chantal; Oranje, Bob; Madsen, Gitte Falcher

    2017-01-01

    Children with autism spectrum disorders (ASD) often show changes in (automatic) auditory processing. Electrophysiology provides a method to study auditory processing, by investigating event-related potentials such as mismatch negativity (MMN) and P3a-amplitude. However, findings on MMN in autism...... a hyper-responsivity at the attentional level. In addition, as similar MMN deficits are found in schizophrenia, these MMN results may explain some of the frequently reported increased risk of children with ASD to develop schizophrenia later in life. Autism Res 2017, 10: 1857–1865....

  9. Perceptual processing of a complex auditory context

    DEFF Research Database (Denmark)

    Quiroga Martinez, David Ricardo; Hansen, Niels Christian; Højlund, Andreas

    The mismatch negativity (MMN) is a brain response elicited by deviants in a series of repetitive sounds. It reflects the perception of change in low-level sound features and reliably measures perceptual auditory memory. However, most MMN studies use simple tone patterns as stimuli, failing...

  10. Enhanced Excitatory Connectivity and Disturbed Sound Processing in the Auditory Brainstem of Fragile X Mice.

    Science.gov (United States)

    Garcia-Pino, Elisabet; Gessele, Nikodemus; Koch, Ursula

    2017-08-02

    Hypersensitivity to sounds is one of the prevalent symptoms in individuals with Fragile X syndrome (FXS). It manifests behaviorally early during development and is often used as a landmark for treatment efficacy. However, the physiological mechanisms and circuit-level alterations underlying this aberrant behavior remain poorly understood. Using the mouse model of FXS ( Fmr1 KO ), we demonstrate that functional maturation of auditory brainstem synapses is impaired in FXS. Fmr1 KO mice showed a greatly enhanced excitatory synaptic input strength in neurons of the lateral superior olive (LSO), a prominent auditory brainstem nucleus, which integrates ipsilateral excitation and contralateral inhibition to compute interaural level differences. Conversely, the glycinergic, inhibitory input properties remained unaffected. The enhanced excitation was the result of an increased number of cochlear nucleus fibers converging onto one LSO neuron, without changing individual synapse properties. Concomitantly, immunolabeling of excitatory ending markers revealed an increase in the immunolabeled area, supporting abnormally elevated excitatory input numbers. Intrinsic firing properties were only slightly enhanced. In line with the disturbed development of LSO circuitry, auditory processing was also affected in adult Fmr1 KO mice as shown with single-unit recordings of LSO neurons. These processing deficits manifested as an increase in firing rate, a broadening of the frequency response area, and a shift in the interaural level difference function of LSO neurons. Our results suggest that this aberrant synaptic development of auditory brainstem circuits might be a major underlying cause of the auditory processing deficits in FXS. SIGNIFICANCE STATEMENT Fragile X Syndrome (FXS) is the most common inheritable form of intellectual impairment, including autism. A core symptom of FXS is extreme sensitivity to loud sounds. This is one reason why individuals with FXS tend to avoid social

  11. Perceptual Plasticity for Auditory Object Recognition

    Science.gov (United States)

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

    2017-01-01

    In our auditory environment, we rarely experience the exact acoustic waveform twice. This is especially true for communicative signals that have meaning for listeners. In speech and music, the acoustic signal changes as a function of the talker (or instrument), speaking (or playing) rate, and room acoustics, to name a few factors. Yet, despite this acoustic variability, we are able to recognize a sentence or melody as the same across various kinds of acoustic inputs and determine meaning based on listening goals, expectations, context, and experience. The recognition process relates acoustic signals to prior experience despite variability in signal-relevant and signal-irrelevant acoustic properties, some of which could be considered as “noise” in service of a recognition goal. However, some acoustic variability, if systematic, is lawful and can be exploited by listeners to aid in recognition. Perceivable changes in systematic variability can herald a need for listeners to reorganize perception and reorient their attention to more immediately signal-relevant cues. This view is not incorporated currently in many extant theories of auditory perception, which traditionally reduce psychological or neural representations of perceptual objects and the processes that act on them to static entities. While this reduction is likely done for the sake of empirical tractability, such a reduction may seriously distort the perceptual process to be modeled. We argue that perceptual representations, as well as the processes underlying perception, are dynamically determined by an interaction between the uncertainty of the auditory signal and constraints of context. This suggests that the process of auditory recognition is highly context-dependent in that the identity of a given auditory object may be intrinsically tied to its preceding context. To argue for the flexible neural and psychological updating of sound-to-meaning mappings across speech and music, we draw upon examples

  12. Auditory stimulus timing influences perceived duration of co-occurring visual stimuli

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    Vincenzo eRomei

    2011-09-01

    Full Text Available There is increasing interest in multisensory influences upon sensory-specific judgements, such as when auditory stimuli affect visual perception. Here we studied whether the duration of an auditory event can objectively affect the perceived duration of a co-occurring visual event. On each trial, participants were presented with a pair of successive flashes and had to judge whether the first or second was longer. Two beeps were presented with the flashes. The order of short and long stimuli could be the same across audition and vision (audiovisual congruent or reversed, so that the longer flash was accompanied by the shorter beep and vice versa (audiovisual incongruent; or the two beeps could have the same duration as each other. Beeps and flashes could onset synchronously or asynchronously. In a further control experiment, the beep durations were much longer (tripled than the flashes. Results showed that visual duration-discrimination sensitivity (d' was significantly higher for congruent (and significantly lower for incongruent audiovisual synchronous combinations, relative to the visual only presentation. This effect was abolished when auditory and visual stimuli were presented asynchronously, or when sound durations tripled those of flashes. We conclude that the temporal properties of co-occurring auditory stimuli influence the perceived duration of visual stimuli and that this can reflect genuine changes in visual sensitivity rather than mere response bias.

  13. Auditory and Visual Sensations

    CERN Document Server

    Ando, Yoichi

    2010-01-01

    Professor Yoichi Ando, acoustic architectural designer of the Kirishima International Concert Hall in Japan, presents a comprehensive rational-scientific approach to designing performance spaces. His theory is based on systematic psychoacoustical observations of spatial hearing and listener preferences, whose neuronal correlates are observed in the neurophysiology of the human brain. A correlation-based model of neuronal signal processing in the central auditory system is proposed in which temporal sensations (pitch, timbre, loudness, duration) are represented by an internal autocorrelation representation, and spatial sensations (sound location, size, diffuseness related to envelopment) are represented by an internal interaural crosscorrelation function. Together these two internal central auditory representations account for the basic auditory qualities that are relevant for listening to music and speech in indoor performance spaces. Observed psychological and neurophysiological commonalities between auditor...

  14. Measuring Auditory Selective Attention using Frequency Tagging

    Directory of Open Access Journals (Sweden)

    Hari M Bharadwaj

    2014-02-01

    Full Text Available Frequency tagging of sensory inputs (presenting stimuli that fluctuate periodically at rates to which the cortex can phase lock has been used to study attentional modulation of neural responses to inputs in different sensory modalities. For visual inputs, the visual steady-state response (VSSR at the frequency modulating an attended object is enhanced, while the VSSR to a distracting object is suppressed. In contrast, the effect of attention on the auditory steady-state response (ASSR is inconsistent across studies. However, most auditory studies analyzed results at the sensor level or used only a small number of equivalent current dipoles to fit cortical responses. In addition, most studies of auditory spatial attention used dichotic stimuli (independent signals at the ears rather than more natural, binaural stimuli. Here, we asked whether these methodological choices help explain discrepant results. Listeners attended to one of two competing speech streams, one simulated from the left and one from the right, that were modulated at different frequencies. Using distributed source modeling of magnetoencephalography results, we estimate how spatially directed attention modulates the ASSR in neural regions across the whole brain. Attention enhances the ASSR power at the frequency of the attended stream in the contralateral auditory cortex. The attended-stream modulation frequency also drives phase-locked responses in the left (but not right precentral sulcus (lPCS, a region implicated in control of eye gaze and visual spatial attention. Importantly, this region shows no phase locking to the distracting stream suggesting that the lPCS in engaged in an attention-specific manner. Modeling results that take account of the geometry and phases of the cortical sources phase locked to the two streams (including hemispheric asymmetry of lPCS activity help partly explain why past ASSR studies of auditory spatial attention yield seemingly contradictory

  15. Modularity in Sensory Auditory Memory

    OpenAIRE

    Clement, Sylvain; Moroni, Christine; Samson, Séverine

    2004-01-01

    The goal of this paper was to review various experimental and neuropsychological studies that support the modular conception of auditory sensory memory or auditory short-term memory. Based on initial findings demonstrating that verbal sensory memory system can be dissociated from a general auditory memory store at the functional and anatomical levels. we reported a series of studies that provided evidence in favor of multiple auditory sensory stores specialized in retaining eit...

  16. Solar Sail Material Performance Property Response to Space Environmental Effects

    Science.gov (United States)

    Edwards, David L.; Semmel, Charles; Hovater, Mary; Nehls, Mary; Gray, Perry; Hubbs, Whitney; Wertz, George

    2004-01-01

    The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) continues research into the utilization of photonic materials for spacecraft propulsion. Spacecraft propulsion, using photonic materials, will be achieved using a solar sail. A solar sail operates on the principle that photons, originating from the sun, impart pressure to the sail and therefore provide a source for spacecraft propulsion. The pressure imparted to a solar sail can be increased, up to a factor of two, if the sun-facing surface is perfectly reflective. Therefore, these solar sails are generally composed of a highly reflective metallic sun-facing layer, a thin polymeric substrate and occasionally a highly emissive back surface. Near term solar sail propelled science missions are targeting the Lagrange point 1 (Ll) as well as locations sunward of L1 as destinations. These near term missions include the Solar Polar Imager and the L1 Diamond. The Environmental Effects Group at NASA s Marshall Space Flight Center (MSFC) continues to actively characterize solar sail material in preparation for these near term solar sail missions. Previous investigations indicated that space environmental effects on sail material thermo-optical properties were minimal and would not significantly affect the propulsion efficiency of the sail. These investigations also indicated that the sail material mechanical stability degrades with increasing radiation exposure. This paper will further quantify the effect of space environmental exposure on the mechanical properties of candidate sail materials. Candidate sail materials for these missions include Aluminum coated Mylar[TM], Teonex[TM], and CPl (Colorless Polyimide). These materials were subjected to uniform radiation doses of electrons and protons in individual exposures sequences. Dose values ranged from 100 Mrads to over 5 Grads. The engineering performance property responses of thermo-optical and mechanical properties were

  17. Effects of transcranial direct current stimulation on the auditory mismatch negativity response and working memory performance in schizophrenia: a pilot study.

    Science.gov (United States)

    Impey, Danielle; Baddeley, Ashley; Nelson, Renee; Labelle, Alain; Knott, Verner

    2017-11-01

    Cognitive impairment has been proposed to be the core feature of schizophrenia (Sz). Transcranial direct current stimulation (tDCS) is a non-invasive form of brain stimulation which can improve cognitive function in healthy participants and in psychiatric patients with cognitive deficits. tDCS has been shown to improve cognition and hallucination symptoms in Sz, a disorder also associated with marked sensory processing deficits. Recent findings in healthy controls demonstrate that anodal tDCS increases auditory deviance detection, as measured by the brain-based event-related potential, mismatch negativity (MMN), which is a putative biomarker of Sz that has been proposed as a target for treatment of Sz cognition. This pilot study conducted a randomized, double-blind assessment of the effects of pre- and post-tDCS on MMN-indexed auditory discrimination in 12 Sz patients, moderated by auditory hallucination (AH) presence, as well as working memory performance. Assessments were conducted in three sessions involving temporal and frontal lobe anodal stimulation (to transiently excite local brain activity), and one control session involving 'sham' stimulation (meaning with the device turned off, i.e., no stimulation). Results demonstrated a trend for pitch MMN amplitude to increase with anodal temporal tDCS, which was significant in a subgroup of Sz individuals with AHs. Anodal frontal tDCS significantly increased WM performance on the 2-back task, which was found to positively correlate with MMN-tDCS effects. The findings contribute to our understanding of tDCS effects for sensory processing deficits and working memory performance in Sz and may have implications for psychiatric disorders with sensory deficits.

  18. Tinnitus intensity dependent gamma oscillations of the contralateral auditory cortex.

    Directory of Open Access Journals (Sweden)

    Elsa van der Loo

    Full Text Available BACKGROUND: Non-pulsatile tinnitus is considered a subjective auditory phantom phenomenon present in 10 to 15% of the population. Tinnitus as a phantom phenomenon is related to hyperactivity and reorganization of the auditory cortex. Magnetoencephalography studies demonstrate a correlation between gamma band activity in the contralateral auditory cortex and the presence of tinnitus. The present study aims to investigate the relation between objective gamma-band activity in the contralateral auditory cortex and subjective tinnitus loudness scores. METHODS AND FINDINGS: In unilateral tinnitus patients (N = 15; 10 right, 5 left source analysis of resting state electroencephalographic gamma band oscillations shows a strong positive correlation with Visual Analogue Scale loudness scores in the contralateral auditory cortex (max r = 0.73, p<0.05. CONCLUSION: Auditory phantom percepts thus show similar sound level dependent activation of the contralateral auditory cortex as observed in normal audition. In view of recent consciousness models and tinnitus network models these results suggest tinnitus loudness is coded by gamma band activity in the contralateral auditory cortex but might not, by itself, be responsible for tinnitus perception.

  19. Auditory and visual spatial impression: Recent studies of three auditoria

    Science.gov (United States)

    Nguyen, Andy; Cabrera, Densil

    2004-10-01

    Auditory spatial impression is widely studied for its contribution to auditorium acoustical quality. By contrast, visual spatial impression in auditoria has received relatively little attention in formal studies. This paper reports results from a series of experiments investigating the auditory and visual spatial impression of concert auditoria. For auditory stimuli, a fragment of an anechoic recording of orchestral music was convolved with calibrated binaural impulse responses, which had been made with the dummy head microphone at a wide range of positions in three auditoria and the sound source on the stage. For visual stimuli, greyscale photographs were used, taken at the same positions in the three auditoria, with a visual target on the stage. Subjective experiments were conducted with auditory stimuli alone, visual stimuli alone, and visual and auditory stimuli combined. In these experiments, subjects rated apparent source width, listener envelopment, intimacy and source distance (auditory stimuli), and spaciousness, envelopment, stage dominance, intimacy and target distance (visual stimuli). Results show target distance to be of primary importance in auditory and visual spatial impression-thereby providing a basis for covariance between some attributes of auditory and visual spatial impression. Nevertheless, some attributes of spatial impression diverge between the senses.

  20. Increased BOLD Signals Elicited by High Gamma Auditory Stimulation of the Left Auditory Cortex in Acute State Schizophrenia

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    Hironori Kuga, M.D.

    2016-10-01

    We acquired BOLD responses elicited by click trains of 20, 30, 40 and 80-Hz frequencies from 15 patients with acute episode schizophrenia (AESZ, 14 symptom-severity-matched patients with non-acute episode schizophrenia (NASZ, and 24 healthy controls (HC, assessed via a standard general linear-model-based analysis. The AESZ group showed significantly increased ASSR-BOLD signals to 80-Hz stimuli in the left auditory cortex compared with the HC and NASZ groups. In addition, enhanced 80-Hz ASSR-BOLD signals were associated with more severe auditory hallucination experiences in AESZ participants. The present results indicate that neural over activation occurs during 80-Hz auditory stimulation of the left auditory cortex in individuals with acute state schizophrenia. Given the possible association between abnormal gamma activity and increased glutamate levels, our data may reflect glutamate toxicity in the auditory cortex in the acute state of schizophrenia, which might lead to progressive changes in the left transverse temporal gyrus.

  1. Cross-Modal Perception of Noise-in-Music: Audiences Generate Spiky Shapes in Response to Auditory Roughness in a Novel Electroacoustic Concert Setting.

    Science.gov (United States)

    Liew, Kongmeng; Lindborg, PerMagnus; Rodrigues, Ruth; Styles, Suzy J

    2018-01-01

    Noise has become integral to electroacoustic music aesthetics. In this paper, we define noise as sound that is high in auditory roughness, and examine its effect on cross-modal mapping between sound and visual shape in participants. In order to preserve the ecological validity of contemporary music aesthetics, we developed Rama , a novel interface, for presenting experimentally controlled blocks of electronically generated sounds that varied systematically in roughness, and actively collected data from audience interaction. These sounds were then embedded as musical drones within the overall sound design of a multimedia performance with live musicians, Audience members listened to these sounds, and collectively voted to create the shape of a visual graphic, presented as part of the audio-visual performance. The results of the concert setting were replicated in a controlled laboratory environment to corroborate the findings. Results show a consistent effect of auditory roughness on shape design, with rougher sounds corresponding to spikier shapes. We discuss the implications, as well as evaluate the audience interface.

  2. Cross-Modal Perception of Noise-in-Music: Audiences Generate Spiky Shapes in Response to Auditory Roughness in a Novel Electroacoustic Concert Setting

    Directory of Open Access Journals (Sweden)

    Kongmeng Liew

    2018-02-01

    Full Text Available Noise has become integral to electroacoustic music aesthetics. In this paper, we define noise as sound that is high in auditory roughness, and examine its effect on cross-modal mapping between sound and visual shape in participants. In order to preserve the ecological validity of contemporary music aesthetics, we developed Rama, a novel interface, for presenting experimentally controlled blocks of electronically generated sounds that varied systematically in roughness, and actively collected data from audience interaction. These sounds were then embedded as musical drones within the overall sound design of a multimedia performance with live musicians, Audience members listened to these sounds, and collectively voted to create the shape of a visual graphic, presented as part of the audio–visual performance. The results of the concert setting were replicated in a controlled laboratory environment to corroborate the findings. Results show a consistent effect of auditory roughness on shape design, with rougher sounds corresponding to spikier shapes. We discuss the implications, as well as evaluate the audience interface.

  3. Visual Information Present in Infragranular Layers of Mouse Auditory Cortex.

    Science.gov (United States)

    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.

  4. Dynamic soil properties in response to anthropogenic disturbance

    Science.gov (United States)

    Vanacker, Veerle; Ortega, Raúl

    2013-04-01

    Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical erosion, with direct implications on local biogeochemical cycling. However, the feedbacks between soil erosion, chemical weathering and biogeochemical cycling in response to anthropogenic forcing are not yet fully understood. Here, we study dynamic soil properties for a rapidly changing anthropogenic landscape, and focus on the coupling between physical erosion, soil production and soil chemical weathering. The archaeological site of Santa Maria de Melque (Toledo, Central Spain) was selected for its remarkably long occupation history dating back to the 7th century AD. As part of the agricultural complex, four retention reservoirs were built in the Early Middle Ages. The sedimentary archive was used to track the evolution in sedimentation rates and geochemical properties of the sediment. Catchment-wide soil erosion rates vary slightly between the various occupation phases (7th century-now), but are of the same magnitude as the cosmogenic nuclide-derived erosion rates. However, there exists large spatial variation in physical erosion rates that are coupled with chemical weathering intensities. The sedimentary records suggest that there are important changes in the spatial pattern of sediment source areas through time as a result of changing land use patterns

  5. Auditory Memory for Timbre

    Science.gov (United States)

    McKeown, Denis; Wellsted, David

    2009-01-01

    Psychophysical studies are reported examining how the context of recent auditory stimulation may modulate the processing of new sounds. The question posed is how recent tone stimulation may affect ongoing performance in a discrimination task. In the task, two complex sounds occurred in successive intervals. A single target component of one complex…

  6. Auditory evacuation beacons

    NARCIS (Netherlands)

    Wijngaarden, S.J. van; Bronkhorst, A.W.; Boer, L.C.

    2005-01-01

    Auditory evacuation beacons can be used to guide people to safe exits, even when vision is totally obscured by smoke. Conventional beacons make use of modulated noise signals. Controlled evacuation experiments show that such signals require explicit instructions and are often misunderstood. A new

  7. Shaping the aging brain: Role of auditory input patterns in the emergence of auditory cortical impairments

    Directory of Open Access Journals (Sweden)

    Brishna Soraya Kamal

    2013-09-01

    Full Text Available Age-related impairments in the primary auditory cortex (A1 include poor tuning selectivity, neural desynchronization and degraded responses to low-probability sounds. These changes have been largely attributed to reduced inhibition in the aged brain, and are thought to contribute to substantial hearing impairment in both humans and animals. Since many of these changes can be partially reversed with auditory training, it has been speculated that they might not be purely degenerative, but might rather represent negative plastic adjustments to noisy or distorted auditory signals reaching the brain. To test this hypothesis, we examined the impact of exposing young adult rats to 8 weeks of low-grade broadband noise on several aspects of A1 function and structure. We then characterized the same A1 elements in aging rats for comparison. We found that the impact of noise exposure on A1 tuning selectivity, temporal processing of auditory signal and responses to oddball tones was almost indistinguishable from the effect of natural aging. Moreover, noise exposure resulted in a reduction in the population of parvalbumin inhibitory interneurons and cortical myelin as previously documented in the aged group. Most of these changes reversed after returning the rats to a quiet environment. These results support the hypothesis that age-related changes in A1 have a strong activity-dependent component and indicate that the presence or absence of clear auditory input patterns might be a key factor in sustaining adult A1 function.

  8. Elastic Properties and Enhanced Piezoelectric Response at Morphotropic Phase Boundaries

    Directory of Open Access Journals (Sweden)

    Francesco Cordero

    2015-12-01

    Full Text Available The search for improved piezoelectric materials is based on the morphotropic phase boundaries (MPB between ferroelectric phases with different crystal symmetry and available directions for the spontaneous polarization. Such regions of the composition x − T phase diagrams provide the conditions for minimal anisotropy with respect to the direction of the polarization, so that the polarization can easily rotate maintaining a substantial magnitude, while the near verticality of the TMPB(x boundary extends the temperature range of the resulting enhanced piezoelectricity. Another consequence of the quasi-isotropy of the free energy is a reduction of the domain walls energies, with consequent formation of domain structures down to nanoscale. Disentangling the extrinsic and intrinsic contributions to the piezoelectricity in such conditions requires a high level of sophistication from the techniques and analyses for studying the structural, ferroelectric and dielectric properties. The elastic characterization is extremely useful in clarifying the phenomenology and mechanisms related to ferroelectric MPBs. The relationship between dielectric, elastic and piezoelectric responses is introduced in terms of relaxation of defects with electric dipole and elastic quadrupole, and extended to the response near phase transitions in the framework of the Landau theory. An account is provided of the anelastic experiments, from torsional pendulum to Brillouin scattering, that provided new important information on ferroelectric MPBs, including PZT, PMN-PT, NBT-BT, BCTZ, and KNN-based systems.

  9. Elastic Properties and Enhanced Piezoelectric Response at Morphotropic Phase Boundaries

    Science.gov (United States)

    Cordero, Francesco

    2015-01-01

    The search for improved piezoelectric materials is based on the morphotropic phase boundaries (MPB) between ferroelectric phases with different crystal symmetry and available directions for the spontaneous polarization. Such regions of the composition x−T phase diagrams provide the conditions for minimal anisotropy with respect to the direction of the polarization, so that the polarization can easily rotate maintaining a substantial magnitude, while the near verticality of the TMPBx boundary extends the temperature range of the resulting enhanced piezoelectricity. Another consequence of the quasi-isotropy of the free energy is a reduction of the domain walls energies, with consequent formation of domain structures down to nanoscale. Disentangling the extrinsic and intrinsic contributions to the piezoelectricity in such conditions requires a high level of sophistication from the techniques and analyses for studying the structural, ferroelectric and dielectric properties. The elastic characterization is extremely useful in clarifying the phenomenology and mechanisms related to ferroelectric MPBs. The relationship between dielectric, elastic and piezoelectric responses is introduced in terms of relaxation of defects with electric dipole and elastic quadrupole, and extended to the response near phase transitions in the framework of the Landau theory. An account is provided of the anelastic experiments, from torsional pendulum to Brillouin scattering, that provided new important information on ferroelectric MPBs, including PZT, PMN-PT, NBT-BT, BCTZ, and KNN-based systems. PMID:28793707

  10. The human brain maintains contradictory and redundant auditory sensory predictions.

    Directory of Open Access Journals (Sweden)

    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.

  11. Reduced auditory efferent activity in childhood selective mutism.

    Science.gov (United States)

    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.

  12. The effects of divided attention on auditory priming.

    Science.gov (United States)

    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.

  13. Auditory cortical processing in real-world listening: the auditory system going real.

    Science.gov (United States)

    Nelken, Israel; Bizley, Jennifer; Shamma, Shihab A; Wang, Xiaoqin

    2014-11-12

    The auditory sense of humans transforms intrinsically senseless pressure waveforms into spectacularly rich perceptual phenomena: the music of Bach or the Beatles, the poetry of Li Bai or Omar Khayyam, or more prosaically the sense of the world filled with objects emitting sounds that is so important for those of us lucky enough to have hearing. Whereas the early representations of sounds in the auditory system are based on their physical structure, higher auditory centers are thought to represent sounds in terms of their perceptual attributes. In this symposium, we will illustrate the current research into this process, using four case studies. We will illustrate how the spectral and temporal properties of sounds are used to bind together, segregate, categorize, and interpret sound patterns on their way to acquire meaning, with important lessons to other sensory systems as well. Copyright © 2014 the authors 0270-6474/14/3415135-04$15.00/0.

  14. The relation between working memory capacity and auditory lateralization in children with auditory processing disorders.

    Science.gov (United States)

    Moossavi, Abdollah; Mehrkian, Saiedeh; Lotfi, Yones; Faghihzadeh, Soghrat; sajedi, Hamed

    2014-11-01

    Auditory processing disorder (APD) describes a complex and heterogeneous disorder characterized by poor speech perception, especially in noisy environments. APD may be responsible for a range of sensory processing deficits associated with learning difficulties. There is no general consensus about the nature of APD and how the disorder should be assessed or managed. This study assessed the effect of cognition abilities (working memory capacity) on sound lateralization in children with auditory processing disorders, in order to determine how "auditory cognition" interacts with APD. The participants in this cross-sectional comparative study were 20 typically developing and 17 children with a diagnosed auditory processing disorder (9-11 years old). Sound lateralization abilities investigated using inter-aural time (ITD) differences and inter-aural intensity (IID) differences with two stimuli (high pass and low pass noise) in nine perceived positions. Working memory capacity was evaluated using the non-word repetition, and forward and backward digits span tasks. Linear regression was employed to measure the degree of association between working memory capacity and localization tests between the two groups. Children in the APD group had consistently lower scores than typically developing subjects in lateralization and working memory capacity measures. The results showed working memory capacity had significantly negative correlation with ITD errors especially with high pass noise stimulus but not with IID errors in APD children. The study highlights the impact of working memory capacity on auditory lateralization. The finding of this research indicates that the extent to which working memory influences auditory processing depend on the type of auditory processing and the nature of stimulus/listening situation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Pre-attentive, context-specific representation of fear memory in the auditory cortex of rat.

    Directory of Open Access Journals (Sweden)

    Akihiro Funamizu

    Full Text Available Neural representation in the auditory cortex is rapidly modulated by both top-down attention and bottom-up stimulus properties, in order to improve perception in a given context. Learning-induced, pre-attentive, map plasticity has been also studied in the anesthetized cortex; however, little attention has been paid to rapid, context-dependent modulation. We hypothesize that context-specific learning leads to pre-attentively modulated, multiplex representation in the auditory cortex. Here, we investigate map plasticity in the auditory cortices of anesthetized rats conditioned in a context-dependent manner, such that a conditioned stimulus (CS of a 20-kHz tone and an unconditioned stimulus (US of a mild electrical shock were associated only under a noisy auditory context, but not in silence. After the conditioning, although no distinct plasticity was found in the tonotopic map, tone-evoked responses were more noise-resistive than pre-conditioning. Yet, the conditioned group showed a reduced spread of activation to each tone with noise, but not with silence, associated with a sharpening of frequency tuning. The encoding accuracy index of neurons showed that conditioning deteriorated the accuracy of tone-frequency representations in noisy condition at off-CS regions, but not at CS regions, suggesting that arbitrary tones around the frequency of the CS were more likely perceived as the CS in a specific context, where CS was associated with US. These results together demonstrate that learning-induced plasticity in the auditory cortex occurs in a context-dependent manner.

  16. Pre-attentive, context-specific representation of fear memory in the auditory cortex of rat.

    Science.gov (United States)

    Funamizu, Akihiro; Kanzaki, Ryohei; Takahashi, Hirokazu

    2013-01-01

    Neural representation in the auditory cortex is rapidly modulated by both top-down attention and bottom-up stimulus properties, in order to improve perception in a given context. Learning-induced, pre-attentive, map plasticity has been also studied in the anesthetized cortex; however, little attention has been paid to rapid, context-dependent modulation. We hypothesize that context-specific learning leads to pre-attentively modulated, multiplex representation in the auditory cortex. Here, we investigate map plasticity in the auditory cortices of anesthetized rats conditioned in a context-dependent manner, such that a conditioned stimulus (CS) of a 20-kHz tone and an unconditioned stimulus (US) of a mild electrical shock were associated only under a noisy auditory context, but not in silence. After the conditioning, although no distinct plasticity was found in the tonotopic map, tone-evoked responses were more noise-resistive than pre-conditioning. Yet, the conditioned group showed a reduced spread of activation to each tone with noise, but not with silence, associated with a sharpening of frequency tuning. The encoding accuracy index of neurons showed that conditioning deteriorated the accuracy of tone-frequency representations in noisy condition at off-CS regions, but not at CS regions, suggesting that arbitrary tones around the frequency of the CS were more likely perceived as the CS in a specific context, where CS was associated with US. These results together demonstrate that learning-induced plasticity in the auditory cortex occurs in a context-dependent manner.

  17. Processamento auditivo: comparação entre potenciais evocados auditivos de média latência e testes de padrões temporais Auditory processing: comparision between auditory middle latency response and temporal pattern tests

    Directory of Open Access Journals (Sweden)

    Eliane Schochat

    2009-06-01

    Full Text Available OBJETIVO: verificar a concordância entre os resultados da avaliação do Potencial Evocado Auditivo de Média Latência e testes de padrões temporais. MÉTODOS: foram avaliados 155 sujeitos de ambos os sexos, idade entre sete e 16 anos, com audição periférica normal. Os sujeitos foram submetidos aos testes de Padrão de Frequência e Duração e Potenciais Evocados auditivos de Média Latência. RESULTADOS: os sujeitos foram distribuídos em dois grupos: normal ou alterado para o processamento auditivo. O índice de alteração foi em torno de 30%, exceto para Potencial Evocado Auditivo de Média Latência que foi pouco menor (17,4%. Os padrões de frequência e duração foram concordantes até 12 anos. A partir dos 13 anos, observou-se maior ocorrência de alteração no padrão de frequência que no padrão de duração. Os padrões de frequência e duração (orelhas direita e esquerda e Potencial Evocado Auditivo de Média Latência não foram concordantes. Para 7 e 8 anos a combinação padrão de frequência e duração normal / Média Latência alterado tem maior ocorrência que a combinação padrão de frequência e duração alterada / Média Latência normal. Nas demais idades, ocorreu o contrário. Não houve diferença estatística entre as faixas etárias quanto à distribuição de normal e alterado no padrão de frequência (orelhas direita e esquerda, nem para o Potencial Evocado Auditivo de Média Latência, com exceção do padrão de duração para o grupo de 9 e 10 anos. CONCLUSÃO: não houve concordância entre os resultados do Potencial Evocado Auditivo de Média Latência e os testes de padrões temporais aplicados.PURPOSE: to check the concordance between the Middle Latency Response and temporal processing tests. METHODS: 155 normal hearing subjects of both genders (age group range between 7 to 16 years were evaluated with the Pitch and Duration Pattern Tests (behavioral and Middle Latency Response

  18. Subcortical pathways: Towards a better understanding of auditory disorders.

    Science.gov (United States)

    Felix, Richard A; Gourévitch, Boris; Portfors, Christine V

    2018-05-01

    Hearing loss is a significant problem that affects at least 15% of the population. This percentage, however, is likely significantly higher because of a variety of auditory disorders that are not identifiable through traditional tests of peripheral hearing ability. In these disorders, individuals have difficulty understanding speech, particularly in noisy environments, even though the sounds are loud enough to hear. The underlying mechanisms leading to such deficits are not well understood. To enable the development of suitable treatments to alleviate or prevent such disorders, the affected processing pathways must be identified. Historically, mechanisms underlying speech processing have been thought to be a property of the auditory cortex and thus the study of auditory disorders has largely focused on cortical impairments and/or cognitive processes. As we review here, however, there is strong evidence to suggest that, in fact, deficits in subcortical pathways play a significant role in auditory disorders. In this review, we highlight the role of the auditory brainstem and midbrain in processing complex sounds and discuss how deficits in these regions may contribute to auditory dysfunction. We discuss current research with animal models of human hearing and then consider human studies that implicate impairments in subcortical processing that may contribute to auditory disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Potenciais Evocados Auditivos de Estado Estável no diagnóstico audiológico infantil: uma comparação com os Potenciais Evocados Auditivos de Tronco Encefálico Steady-state auditory evoked responses in audiological diagnosis in children: a comparison with brainstem evoked auditory responses

    Directory of Open Access Journals (Sweden)

    Gabriela Ribeiro Ivo Rodrigues

    2010-02-01

    Full Text Available Os Potenciais Evocados Auditivos de Estado Estável (PEAEE têm sido apontados como uma técnica promissora na avaliação audiológica infantil. OBJETIVO: Investigar o nível de concordância entre os resultados dos PEAEE e dos Potenciais Evocados Auditivos de Tronco Encefálico (PEATE-clique em um grupo de crianças com perda auditiva sensorioneural, averiguando assim a aplicabilidade clínica desta técnica na avaliação audiológica infantil. FORMA DE ESTUDO: Clínico prospectivo de coorte transversal. MATERIAL E MÉTODO: 15 crianças com idade entre dois e 36 meses e diagnóstico de perda auditiva sensorioneural. A concordância entre as respostas dos dois testes foi avaliada por meio do coeficiente de correlação intraclasse e o teste de McNemar comparou os dois testes quanto à probabilidade de ocorrência de resposta. RESULTADOS: Os coeficientes de correlação encontrados foram 0,70; 0,64; 0,49; 0,69; 0,63 e 0,68 respectivamente para as frequências de 1, 2, 4, 1-2, 2-4 e 1-2-4kHz. No teste de McNemar foi obtido p=0.000, indicando que a probabilidade de se obter resposta presente nos dois testes não é igual, sendo maior nos PEAEE. CONCLUSÃO: A boa concordância observada entre as técnicas sugere que um exame pode ser complementar ao outro. Os PEAEE, entretanto, promoveram informações adicionais nos casos de perdas severas e profundas, acrescentando dados importantes para a reabilitação destas crianças e proporcionando maior precisão no diagnóstico audiológico.Auditory Steady-State Responses (ASSR are being recognized as a promising technique in the assessment of hearing in children. AIM: To investigate the agreement level between results obtained from ASSR and click-ABR in a group of children with sensorineural hearing loss, in order to study the clinical applicability of this technique to evaluate the hearing status in young children. STUDY DESIGN: clinical prospective with a cross-sectional cohort. MATERIALS AND METHODS

  20. A Case of Generalized Auditory Agnosia with Unilateral Subcortical Brain Lesion

    Science.gov (United States)

    Suh, Hyee; Kim, Soo Yeon; Kim, Sook Hee; Chang, Jae Hyeok; Shin, Yong Beom; Ko, Hyun-Yoon

    2012-01-01

    The mechanisms and functional anatomy underlying the early stages of speech perception are still not well understood. Auditory agnosia is a deficit of auditory object processing defined as a disability to recognize spoken languages and/or nonverbal environmental sounds and music despite adequate hearing while spontaneous speech, reading and writing are preserved. Usually, either the bilateral or unilateral temporal lobe, especially the transverse gyral lesions, are responsible for auditory agnosia. Subcortical lesions without cortical damage rarely causes auditory agnosia. We present a 73-year-old right-handed male with generalized auditory agnosia caused by a unilateral subcortical lesion. He was not able to repeat or dictate but to perform fluent and comprehensible speech. He could understand and read written words and phrases. His auditory brainstem evoked potential and audiometry were intact. This case suggested that the subcortical lesion involving unilateral acoustic radiation could cause generalized auditory agnosia. PMID:23342322

  1. Visual versus auditory Simon effect: A behavioural and physiological investigation.

    Science.gov (United States)

    D'Ascenzo, Stefania; Lugli, Luisa; Baroni, Giulia; Guidotti, Roberto; Rubichi, Sandro; Iani, Cristina; Nicoletti, Roberto

    2018-04-01

    This study investigated whether the visual and auditory Simon effects could be accounted for by the same mechanism. In a single experiment, we performed a detailed comparison of the visual and the auditory Simon effects arising in behavioural responses and in pupil dilation, a psychophysiological measure considered as a marker of the cognitive effort induced by conflict processing. To address our question, we performed sequential and distributional analyses on both reaction times and pupil dilation. Results confirmed that the mechanisms underlying the visual and auditory Simon effects are functionally equivalent in terms of the interaction between unconditional and conditional response processes. The two modalities, however, differ with respect to the strength of their activation and inhibition. Importantly, pupillary data mirrored the pattern observed in behavioural data for both tasks, adding physiological evidence to the current literature on the processing of visual and auditory information in a conflict task.

  2. The spectrotemporal filter mechanism of auditory selective attention

    Science.gov (United States)

    Lakatos, Peter; Musacchia, Gabriella; O’Connell, Monica N.; Falchier, Arnaud Y.; Javitt, Daniel C.; Schroeder, Charles E.

    2013-01-01

    SUMMARY While we have convincing evidence that attention to auditory stimuli modulates neuronal responses at or before the level of primary auditory cortex (A1), the underlying physiological mechanisms are unknown. We found that attending to rhythmic auditory streams resulted in the entrainment of ongoing oscillatory activity reflecting rhythmic excitability fluctuations in A1. Strikingly, while the rhythm of the entrained oscillations in A1 neuronal ensembles reflected the temporal structure of the attended stream, the phase depended on the attended frequency content. Counter-phase entrainment across differently tuned A1 regions resulted in both the amplification and sharpening of responses at attended time points, in essence acting as a spectrotemporal filter mechanism. Our data suggest that selective attention generates a dynamically evolving model of attended auditory stimulus streams in the form of modulatory subthreshold oscillations across tonotopically organized neuronal ensembles in A1 that enhances the representation of attended stimuli. PMID:23439126

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

    Science.gov (United States)

    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.

  4. A virtual auditory environment for investigating the auditory signal processing of realistic sounds

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel; Buchholz, Jörg

    2008-01-01

    In the present study, a novel multichannel loudspeaker-based virtual auditory environment (VAE) is introduced. The VAE aims at providing a versatile research environment for investigating the auditory signal processing in real environments, i.e., considering multiple sound sources and room...... reverberation. The environment is based on the ODEON room acoustic simulation software to render the acoustical scene. ODEON outputs are processed using a combination of different order Ambisonic techniques to calculate multichannel room impulse responses (mRIR). Auralization is then obtained by the convolution...... the VAE development, special care was taken in order to achieve a realistic auditory percept and to avoid “artifacts” such as unnatural coloration. The performance of the VAE has been evaluated and optimized on a 29 loudspeaker setup using both objective and subjective measurement techniques....

  5. Temporal Sequence of Visuo-Auditory Interaction in Multiple Areas of the Guinea Pig Visual Cortex

    Science.gov (United States)

    Nishimura, Masataka; Song, Wen-Jie

    2012-01-01

    Recent studies in humans and monkeys have reported that acoustic stimulation influences visual responses in the primary visual cortex (V1). Such influences can be generated in V1, either by direct auditory projections or by feedback projections from extrastriate cortices. To test these hypotheses, cortical activities were recorded using optical imaging at a high spatiotemporal resolution from multiple areas of the guinea pig visual cortex, to visual and/or acoustic stimulations. Visuo-auditory interactions were evaluated according to differences between responses evoked by combined auditory and visual stimulation, and the sum of responses evoked by separate visual and auditory stimulations. Simultaneous presentation of visual and acoustic stimulations resulted in significant interactions in V1, which occurred earlier than in other visual areas. When acoustic stimulation preceded visual stimulation, significant visuo-auditory interactions were detected only in V1. These results suggest that V1 is a cortical origin of visuo-auditory interaction. PMID:23029483

  6. Biological impact of music and software-based auditory training

    Science.gov (United States)

    Kraus, Nina

    2012-01-01

    Auditory-based communication skills are developed at a young age and are maintained throughout our lives. However, some individuals – both young and old – encounter difficulties in achieving or maintaining communication proficiency. Biological signals arising from hearing sounds relate to real-life communication skills such as listening to speech in noisy environments and reading, pointing to an intersection between hearing and cognition. Musical experience, amplification, and software-based training can improve these biological signals. These findings of biological plasticity, in a variety of subject populations, relate to attention and auditory memory, and represent an integrated auditory system influenced by both sensation and cognition. Learning outcomes The reader will (1) understand that the auditory system is malleable to experience and training, (2) learn the ingredients necessary for auditory learning to successfully be applied to communication, (3) learn that the auditory brainstem response to complex sounds (cABR) is a window into the integrated auditory system, and (4) see examples of how cABR can be used to track the outcome of experience and training. PMID:22789822

  7. Effect of conductive hearing loss on central auditory function.

    Science.gov (United States)

    Bayat, Arash; Farhadi, Mohammad; Emamdjomeh, Hesam; Saki, Nader; Mirmomeni, Golshan; Rahim, Fakher

    It has been demonstrated that long-term Conductive Hearing Loss (CHL) may influence the precise detection of the temporal features of acoustic signals or Auditory Temporal Processing (ATP). It can be argued that ATP may be the underlying component of many central auditory processing capabilities such as speech comprehension or sound localization. Little is known about the consequences of CHL on temporal aspects of central auditory processing. This study was designed to assess auditory temporal processing ability in individuals with chronic CHL. During this analytical cross-sectional study, 52 patients with mild to moderate chronic CHL and 52 normal-hearing listeners (control), aged between 18 and 45 year-old, were recruited. In order to evaluate auditory temporal processing, the Gaps-in-Noise (GIN) test was used. The results obtained for each ear were analyzed based on the gap perception threshold and the percentage of correct responses. The average of GIN thresholds was significantly smaller for the control group than for the CHL group for both ears (right: p=0.004; left: phearing for both sides (phearing loss in either group (p>0.05). The results suggest reduced auditory temporal processing ability in adults with CHL compared to normal hearing subjects. Therefore, developing a clinical protocol to evaluate auditory temporal processing in this population is recommended. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  8. Translation and adaptation of functional auditory performance indicators (FAPI

    Directory of Open Access Journals (Sweden)

    Karina Ferreira

    2011-12-01

    Full Text Available Work with deaf children has gained new attention since the expectation and goal of therapy has expanded to language development and subsequent language learning. Many clinical tests were developed for evaluation of speech sound perception in young children in response to the need for accurate assessment of hearing skills that developed from the use of individual hearing aids or cochlear implants. These tests also allow the evaluation of the rehabilitation program. However, few of these tests are available in Portuguese. Evaluation with the Functional Auditory Performance Indicators (FAPI generates a child's functional auditory skills profile, which lists auditory skills in an integrated and hierarchical order. It has seven hierarchical categories, including sound awareness, meaningful sound, auditory feedback, sound source localizing, auditory discrimination, short-term auditory memory, and linguistic auditory processing. FAPI evaluation allows the therapist to map the child's hearing profile performance, determine the target for increasing the hearing abilities, and develop an effective therapeutic plan. Objective: Since the FAPI is an American test, the inventory was adapted for application in the Brazilian population. Material and Methods: The translation was done following the steps of translation and back translation, and reproducibility was evaluated. Four translated versions (two originals and two back-translated were compared, and revisions were done to ensure language adaptation and grammatical and idiomatic equivalence. Results: The inventory was duly translated and adapted. Conclusion: Further studies about the application of the translated FAPI are necessary to make the test practicable in Brazilian clinical use.

  9. An anatomical and functional topography of human auditory cortical areas

    Directory of Open Access Journals (Sweden)

    Michelle eMoerel

    2014-07-01

    Full Text Available While advances in magnetic resonance imaging (MRI throughout the last decades have enabled the detailed anatomical and functional inspection of the human brain non-invasively, to date there is no consensus regarding the precise subdivision and topography of the areas forming the human auditory cortex. Here, we propose a topography of the human auditory areas based on insights on the anatomical and functional properties of human auditory areas as revealed by studies of cyto- and myelo-architecture and fMRI investigations at ultra-high magnetic field (7 Tesla. Importantly, we illustrate that - whereas a group-based approach to analyze functional (tonotopic maps is appropriate to highlight the main tonotopic axis - the examination of tonotopic maps at single subject level is required to detail the topography of primary and non-primary areas that may be more variable across subjects. Furthermore, we show that considering multiple maps indicative of anatomical (i.e. myelination as well as of functional properties (e.g. broadness of frequency tuning is helpful in identifying auditory cortical areas in individual human brains. We propose and discuss a topography of areas that is consistent with old and recent anatomical post mortem characterizations of the human auditory cortex and that may serve as a working model for neuroscience studies of auditory functions.

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

    Science.gov (United States)

    Colletti, Liliana

    2007-09-01

    with a CI, had auditory neuropathy; one child showed total cochlear ossification bilaterally due to meningitis; and one child had profound hearing loss with cochlear fractures after a head injury. Twelve of these children had multiple associated psychomotor handicaps. The retrosigmoid approach was used in all children. Intraoperative electrical auditory brainstem responses (EABRs) and postoperative EABRs and electrical middle latency responses (EMLRs) were performed. Perceptual auditory abilities were evaluated with the Evaluation of Auditory Responses to Speech (EARS) battery - the Listening Progress Profile (LIP), the Meaningful Auditory Integration Scale (MAIS), the Meaningful Use of Speech Scale (MUSS) - and the Category of Auditory Performance (CAP). Cognitive evaluation was performed on seven children using the Leiter International Performance Scale - Revised (LIPS-R) test with the following subtests: Figure ground, Form completion, Sequential order and Repeated pattern. No postoperative complications were observed. All children consistently used their devices for >75% of waking hours and had environmental sound awareness and utterance of words and simple sentences. Their CAP scores ranged from 1 to 7 (average =4); with MAIS they scored 2-97.5% (average =38%); MUSS scores ranged from 5 to 100% (average =49%) and LIP scores from 5 to 100% (average =45%). Owing to associated disabilities, 12 children were given other therapies (e.g. physical therapy and counselling) in addition to speech and aural rehabilitation therapy. Scores for two of the four subtests of LIPS-R in this study increased significantly during the first year of auditory brainstem implant use in all seven children selected for cognitive evaluation.

  11. Auditory interfaces: The human perceiver

    Science.gov (United States)

    Colburn, H. Steven

    1991-01-01

    A brief introduction to the basic auditory abilities of the human perceiver with particular attention toward issues that may be important for the design of auditory interfaces is presented. The importance of appropriate auditory inputs to observers with normal hearing is probably related to the role of hearing as an omnidirectional, early warning system and to its role as the primary vehicle for communication of strong personal feelings.

  12. A Neural Circuit for Auditory Dominance over Visual Perception.

    Science.gov (United States)

    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.

  13. Evolutionary conservation and neuronal mechanisms of auditory perceptual restoration.

    Science.gov (United States)

    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.

  14. Auditory/visual distance estimation: accuracy and variability

    Directory of Open Access Journals (Sweden)

    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.

  15. Hearing after congenital deafness: central auditory plasticity and sensory deprivation.

    Science.gov (United States)

    Kral, A; Hartmann, R; Tillein, J; Heid, S; Klinke, R

    2002-08-01

    The congenitally deaf cat suffers from a degeneration of the inner ear. The organ of Corti bears no hair cells, yet the auditory afferents are preserved. Since these animals have no auditory experience, they were used as a model for congenital deafness. Kittens were equipped with a cochlear implant at different ages and electro-stimulated over a period of 2.0-5.5 months using a monopolar single-channel compressed analogue stimulation strategy (VIENNA-type signal processor). Following a period of auditory experience, we investigated cortical field potentials in response to electrical biphasic pulses applied by means of the cochlear implant. In comparison to naive unstimulated deaf cats and normal hearing cats, the chronically stimulated animals showed larger cortical regions producing middle-latency responses at or above 300 microV amplitude at the contralateral as well as the ipsilateral auditory cortex. The cortex ipsilateral to the chronically stimulated ear did not show any signs of reduced responsiveness when stimulating the 'untrained' ear through a second cochlear implant inserted in the final experiment. With comparable duration of auditory training, the activated cortical area was substantially smaller if implantation had been performed at an older age of 5-6 months. The data emphasize that young sensory systems in cats have a higher capacity for plasticity than older ones and that there is a sensitive period for the cat's auditory system.

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

    Science.gov (United States)

    Zupan, Barbra; Sussman, Joan E

    2009-01-01

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

  17. Auditory Perceptual Abilities Are Associated with Specific Auditory Experience

    Directory of Open Access Journals (Sweden)

    Yael Zaltz

    2017-11-01

    Full Text Available The extent to which auditory experience can shape general auditory perceptual abilities is still under constant debate. Some studies show that specific auditory expertise may have a general effect on auditory perceptual abilities, while others show a more limited influence, exhibited only in a relatively narrow range associated with the area of expertise. The current study addresses this issue by examining experience-dependent enhancement in perceptual abilities in the auditory domain. Three experiments were performed. In the first experiment, 12 pop and rock musicians and 15 non-musicians were tested in frequency discrimination (DLF, intensity discrimination, spectrum discrimination (DLS, and time discrimination (DLT. Results showed significant superiority of the musician group only for the DLF and DLT tasks, illuminating enhanced perceptual skills in the key features of pop music, in which miniscule changes in amplitude and spectrum are not critical to performance. The next two experiments attempted to differentiate between generalization and specificity in the influence of auditory experience, by comparing subgroups of specialists. First, seven guitar players and eight percussionists were tested in the DLF and DLT tasks that were found superior for musicians. Results showed superior abilities on the DLF task for guitar players, though no difference between the groups in DLT, demonstrating some dependency of auditory learning on the specific area of expertise. Subsequently, a third experiment was conducted, testing a possible influence of vowel density in native language on auditory perceptual abilities. Ten native speakers of German (a language characterized by a dense vowel system of 14 vowels, and 10 native speakers of Hebrew (characterized by a sparse vowel system of five vowels, were tested in a formant discrimination task. This is the linguistic equivalent of a DLS task. Results showed that German speakers had superior formant

  18. Selective increase of auditory cortico-striatal coherence during auditory-cued Go/NoGo discrimination learning.

    Directory of Open Access Journals (Sweden)

    Andreas L. Schulz

    2016-01-01

    Full Text Available Goal directed behavior and associated learning processes are tightly linked to neuronal activity in the ventral striatum. Mechanisms that integrate task relevant sensory information into striatal processing during decision making and learning are implicitly assumed in current reinforcementmodels, yet they are still weakly understood. To identify the functional activation of cortico-striatal subpopulations of connections during auditory discrimination learning, we trained Mongolian gerbils in a two-way active avoidance task in a shuttlebox to discriminate between falling and rising frequency modulated tones with identical spectral properties. We assessed functional coupling by analyzing the field-field coherence between the auditory cortex and the ventral striatum of animals performing the task. During the course of training, we observed a selective increase of functionalcoupling during Go-stimulus presentations. These results suggest that the auditory cortex functionally interacts with the ventral striatum during auditory learning and that the strengthening of these functional connections is selectively goal-directed.

  19. Auditory agnosia as a clinical symptom of childhood adrenoleukodystrophy.

    Science.gov (United States)

    Furushima, Wakana; Kaga, Makiko; Nakamura, Masako; Gunji, Atsuko; Inagaki, Masumi

    2015-08-01

    To investigate detailed auditory features in patients with auditory impairment as the first clinical symptoms of childhood adrenoleukodystrophy (CSALD). Three patients who had hearing difficulty as the first clinical signs and/or symptoms of ALD. Precise examination of the clinical characteristics of hearing and auditory function was performed, including assessments of pure tone audiometry, verbal sound discrimination, otoacoustic emission (OAE), and auditory brainstem response (ABR), as well as an environmental sound discrimination test, a sound lateralization test, and a dichotic listening test (DLT). The auditory pathway was evaluated by MRI in each patient. Poor response to calling was detected in all patients. Two patients were not aware of their hearing difficulty, and had been diagnosed with normal hearing by otolaryngologists at first. Pure-tone audiometry disclosed normal hearing in all patients. All patients showed a normal wave V ABR threshold. Three patients showed obvious difficulty in discriminating verbal sounds, environmental sounds, and sound lateralization and strong left-ear suppression in a dichotic listening test. However, once they discriminated verbal sounds, they correctly understood the meaning. Two patients showed elongation of the I-V and III-V interwave intervals in ABR, but one showed no abnormality. MRIs of these three patients revealed signal changes in auditory radiation including in other subcortical areas. The hearing features of these subjects were diagnosed as auditory agnosia and not aphasia. It should be emphasized that when patients are suspected to have hearing impairment but have no abnormalities in pure tone audiometry and/or ABR, this should not be diagnosed immediately as psychogenic response or pathomimesis, but auditory agnosia must also be considered. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  20. Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS.

    Science.gov (United States)

    Chen, Ling-Chia; Sandmann, Pascale; Thorne, Jeremy D; Bleichner, Martin G; Debener, Stefan

    2016-01-01

    Cochlear implant (CI) users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH) controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users' speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS). Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

  1. Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS

    Directory of Open Access Journals (Sweden)

    Ling-Chia Chen

    2016-01-01

    Full Text Available Cochlear implant (CI users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users’ speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS. Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

  2. The importance of individual frequencies of endogenous brain oscillations for auditory cognition - A short review.

    Science.gov (United States)

    Baltus, Alina; Herrmann, Christoph Siegfried

    2016-06-01

    Oscillatory EEG activity in the human brain with frequencies in the gamma range (approx. 30-80Hz) is known to be relevant for a large number of cognitive processes. Interestingly, each subject reveals an individual frequency of the auditory gamma-band response (GBR) that coincides with the peak in the auditory steady state response (ASSR). A common resonance frequency of auditory cortex seems to underlie both the individual frequency of the GBR and the peak of the ASSR. This review sheds light on the functional role of oscillatory gamma activity for auditory processing. For successful processing, the auditory system has to track changes in auditory input over time and store information about past events in memory which allows the construction of auditory objects. Recent findings support the idea of gamma oscillations being involved in the partitioning of auditory input into discrete samples to facilitate higher order processing. We review experiments that seem to suggest that inter-individual differences in the resonance frequency are behaviorally relevant for gap detection and speech processing. A possible application of these resonance frequencies for brain computer interfaces is illustrated with regard to optimized individual presentation rates for auditory input to correspond with endogenous oscillatory activity. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. An Auditory Model with Hearing Loss

    DEFF Research Database (Denmark)

    Nielsen, Lars Bramsløw

    An auditory model based on the psychophysics of hearing has been developed and tested. The model simulates the normal ear or an impaired ear with a given hearing loss. Based on reviews of the current literature, the frequency selectivity and loudness growth as functions of threshold and stimulus...... level have been found and implemented in the model. The auditory model was verified against selected results from the literature, and it was confirmed that the normal spread of masking and loudness growth could be simulated in the model. The effects of hearing loss on these parameters was also...... in qualitative agreement with recent findings. The temporal properties of the ear have currently not been included in the model. As an example of a real-world application of the model, loudness spectrograms for a speech utterance were presented. By introducing hearing loss, the speech sounds became less audible...

  4. Cortical pitch regions in humans respond primarily to resolved harmonics and are located in specific tonotopic regions of anterior auditory cortex.

    Science.gov (United States)

    Norman-Haignere, Sam; Kanwisher, Nancy; McDermott, Josh H

    2013-12-11

    Pitch is a defining perceptual property of many real-world sounds, including music and speech. Classically, theories of pitch perception have differentiated between temporal and spectral cues. These cues are rendered distinct by the frequency resolution of the ear, such that some frequencies produce "resolved" peaks of excitation in the cochlea, whereas others are "unresolved," providing a pitch cue only via their temporal fluctuations. Despite longstanding interest, the neural structures that process pitch, and their relationship to these cues, have remained controversial. Here, using fMRI in humans, we report the following: (1) consistent with previous reports, all subjects exhibited pitch-sensitive cortical regions that responded substantially more to harmonic tones than frequency-matched noise; (2) the response of these regions was mainly driven by spectrally resolved harmonics, although they also exhibited a weak but consistent response to unresolved harmonics relative to noise; (3) the response of pitch-sensitive regions to a parametric manipulation of resolvability tracked psychophysical discrimination thresholds for the same stimuli; and (4) pitch-sensitive regions were localized to specific tonotopic regions of anterior auditory cortex, extending from a low-frequency region of primary auditory cortex into a more anterior and less frequency-selective region of nonprimary auditory cortex. These results demonstrate that cortical pitch responses are located in a stereotyped region of anterior auditory cortex and are predominantly driven by resolved frequency components in a way that mirrors behavior.

  5. The Central Auditory Processing Kit[TM]. Book 1: Auditory Memory [and] Book 2: Auditory Discrimination, Auditory Closure, and Auditory Synthesis [and] Book 3: Auditory Figure-Ground, Auditory Cohesion, Auditory Binaural Integration, and Compensatory Strategies.

    Science.gov (United States)

    Mokhemar, Mary Ann

    This kit for assessing central auditory processing disorders (CAPD), in children in grades 1 through 8 includes 3 books, 14 full-color cards with picture scenes, and a card depicting a phone key pad, all contained in a sturdy carrying case. The units in each of the three books correspond with auditory skill areas most commonly addressed in…

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

    Science.gov (United States)

    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

  7. Listening to another sense: somatosensory integration in the auditory system.

    Science.gov (United States)

    Wu, Calvin; Stefanescu, Roxana A; Martel, David T; Shore, Susan E

    2015-07-01

    Conventionally, sensory systems are viewed as separate entities, each with its own physiological process serving a different purpose. However, many functions require integrative inputs from multiple sensory systems and sensory intersection and convergence occur throughout the central nervous system. The neural processes for hearing perception undergo significant modulation by the two other major sensory systems, vision and somatosensation. This synthesis occurs at every level of the ascending auditory pathway: the cochlear nucleus, inferior colliculus, medial geniculate body and the auditory cortex. In this review, we explore the process of multisensory integration from (1) anatomical (inputs and connections), (2) physiological (cellular responses), (3) functional and (4) pathological aspects. We focus on the convergence between auditory and somatosensory inputs in each ascending auditory station. This review highlights the intricacy of sensory processing and offers a multisensory perspective regarding the understanding of sensory disorders.

  8. Auditory Reserve and the Legacy of Auditory Experience

    Directory of Open Access Journals (Sweden)

    Erika Skoe

    2014-11-01

    Full Text Available Musical training during childhood has been linked to more robust encoding of sound later in life. We take this as evidence for an auditory reserve: a mechanism by which individuals capitalize on earlier life experiences to promote auditory processing. We assert that early auditory experiences guide how the reserve develops and is maintained over the lifetime. Experiences that occur after childhood, or which are limited in nature, are theorized to affect the reserve, although their influence on sensory processing may be less long-lasting and may potentially fade over time if not repeated. This auditory reserve may help to explain individual differences in how individuals cope with auditory impoverishment or loss of sensorineural function.

  9. Visually Evoked Visual-Auditory Changes Associated with Auditory Performance in Children with Cochlear Implants

    Directory of Open Access Journals (Sweden)

    Maojin Liang

    2017-10-01

    Full Text Available Activation of the auditory cortex by visual stimuli has been reported in deaf children. In cochlear implant (CI patients, a residual, more intense cortical activation in the frontotemporal areas in response to photo stimuli was found to be positively associated with poor auditory performance. Our study aimed to investigate the mechanism by which visual processing in CI users activates the auditory-associated cortex during the period after cochlear implantation as well as its relation to CI outcomes. Twenty prelingually deaf children with CI were recruited. Ten children were good CI performers (GCP and ten were poor (PCP. Ten age- and sex- matched normal-hearing children were recruited as controls, and visual evoked potentials (VEPs were recorded. The characteristics of the right frontotemporal N1 component were analyzed. In the prelingually deaf children, higher N1 amplitude was observed compared to normal controls. While the GCP group showed significant decreases in N1 amplitude, and source analysis showed the most significant decrease in brain activity was observed in the primary visual cortex (PVC, with a downward trend in the primary auditory cortex (PAC activity, but these did not occur in the PCP group. Meanwhile, higher PVC activation (comparing to controls before CI use (0M and a significant decrease in source energy after CI use were found to be related to good CI outcomes. In the GCP group, source energy decreased in the visual-auditory cortex with CI use. However, no significant cerebral hemispheric dominance was found. We supposed that intra- or cross-modal reorganization and higher PVC activation in prelingually deaf children may reflect a stronger potential ability of cortical plasticity. Brain activity evolution appears to be related to CI auditory outcomes.

  10. Visually Evoked Visual-Auditory Changes Associated with Auditory Performance in Children with Cochlear Implants.

    Science.gov (United States)

    Liang, Maojin; Zhang, Junpeng; Liu, Jiahao; Chen, Yuebo; Cai, Yuexin; Wang, Xianjun; Wang, Junbo; Zhang, Xueyuan; Chen, Suijun; Li, Xianghui; Chen, Ling; Zheng, Yiqing

    2017-01-01

    Activation of the auditory cortex by visual stimuli has been reported in deaf children. In cochlear implant (CI) patients, a residual, more intense cortical activation in the frontotemporal areas in response to photo stimuli was found to be positively associated with poor auditory performance. Our study aimed to investigate the mechanism by which visual processing in CI users activates the auditory-associated cortex during the period after cochlear implantation as well as its relation to CI outcomes. Twenty prelingually deaf children with CI were recruited. Ten children were good CI performers (GCP) and ten were poor (PCP). Ten age- and sex- matched normal-hearing children were recruited as controls, and visual evoked potentials (VEPs) were recorded. The characteristics of the right frontotemporal N1 component were analyzed. In the prelingually deaf children, higher N1 amplitude was observed compared to normal controls. While the GCP group showed significant decreases in N1 amplitude, and source analysis showed the most significant decrease in brain activity was observed in the primary visual cortex (PVC), with a downward trend in the primary auditory cortex (PAC) activity, but these did not occur in the PCP group. Meanwhile, higher PVC activation (comparing to controls) before CI use (0M) and a significant decrease in source energy after CI use were found to be related to good CI outcomes. In the GCP group, source energy decreased in the visual-auditory cortex with CI use. However, no significant cerebral hemispheric dominance was found. We supposed that intra- or cross-modal reorganization and higher PVC activation in prelingually deaf children may reflect a stronger potential ability of cortical plasticity. Brain activity evolution appears to be related to CI auditory outcomes.

  11. Left hemispheric dominance during auditory processing in a noisy environment

    Directory of Open Access Journals (Sweden)

    Ross Bernhard

    2007-11-01

    Full Text Available Abstract Background In daily life, we are exposed to different sound inputs simultaneously. During neural encoding in the auditory pathway, neural activities elicited by these different sounds interact with each other. In the present study, we investigated neural interactions elicited by masker and amplitude-modulated test stimulus in primary and non-primary human auditory cortex during ipsi-lateral and contra-lateral masking by means of magnetoencephalography (MEG. Results We observed significant decrements of auditory evoked responses and a significant inter-hemispheric difference for the N1m response during both ipsi- and contra-lateral masking. Conclusion The decrements of auditory evoked neural activities during simultaneous masking can be explained by neural interactions evoked by masker and test stimulus in peripheral and central auditory systems. The inter-hemispheric differences of N1m decrements during ipsi- and contra-lateral masking reflect a basic hemispheric specialization contributing to the processing of complex auditory stimuli such as speech signals in noisy environments.

  12. Auditory changes in acromegaly.

    Science.gov (United States)

    Tabur, S; Korkmaz, H; Baysal, E; Hatipoglu, E; Aytac, I; Akarsu, E

    2017-06-01

    The aim of this study is to determine the changes involving auditory system in cases with acromegaly. Otological examinations of 41 cases with acromegaly (uncontrolled n = 22, controlled n = 19) were compared with those of age and gender-matched 24 healthy subjects. Whereas the cases with acromegaly underwent examination with pure tone audiometry (PTA), speech audiometry for speech discrimination (SD), tympanometry, stapedius reflex evaluation and otoacoustic emission tests, the control group did only have otological examination and PTA. Additionally, previously performed paranasal sinus-computed tomography of all cases with acromegaly and control subjects were obtained to measure the length of internal acoustic canal (IAC). PTA values were higher (p acromegaly group was narrower compared to that in control group (p = 0.03 for right ears and p = 0.02 for left ears). When only cases with acromegaly were taken into consideration, PTA values in left ears had positive correlation with growth hormone and insulin-like growth factor-1 levels (r = 0.4, p = 0.02 and r = 0.3, p = 0.03). Of all cases with acromegaly 13 (32%) had hearing loss in at least one ear, 7 (54%) had sensorineural type and 6 (46%) had conductive type hearing loss. Acromegaly may cause certain changes in the auditory system in cases with acromegaly. The changes in the auditory system may be multifactorial causing both conductive and sensorioneural defects.

  13. Exploring the relationship between cortical GABA concentrations, auditory gamma-band responses and development in ASD: Evidence for an altered maturational trajectory in ASD.

    Science.gov (United States)

    Port, Russell G; Gaetz, William; Bloy, Luke; Wang, Dah-Jyuu; Blaskey, Lisa; Kuschner, Emily S; Levy, Susan E; Brodkin, Edward S; Roberts, Timothy P L

    2017-04-01

    Autism spectrum disorder (ASD) is hypothesized to arise from imbalances between excitatory and inhibitory neurotransmission (E/I imbalance). Studies have demonstrated E/I imbalance in individuals with ASD and also corresponding rodent models. One neural process thought to be reliant on E/I balance is gamma-band activity (Gamma), with support arising from observed correlations between motor, as well as visual, Gamma and underlying GABA concentrations in healthy adults. Additionally, decreased Gamma has been observed in ASD individuals and relevant animal models, though the direct relationship between Gamma and GABA concentrations in ASD remains unexplored. This study combined magnetoencephalography (MEG) and edited magnetic resonance spectroscopy (MRS) in 27 typically developing individuals (TD) and 30 individuals with ASD. Auditory cortex localized phase-locked Gamma was compared to resting Superior Temporal Gyrus relative cortical GABA concentrations for both children/adolescents and adults. Children/adolescents with ASD exhibited significantly decreased GABA+/Creatine (Cr) levels, though typical Gamma. Additionally, these children/adolescents lacked the typical maturation of GABA+/Cr concentrations and gamma-band coherence. Furthermore, children/adolescents with ASD additionally failed to exhibit the typical GABA+/Cr to gamma-band coherence association. This altered coupling during childhood/adolescence may result in Gamma decreases observed in the adults with ASD. Therefore, individuals with ASD exhibit improper local neuronal circuitry maturation during a childhood/adolescence critical period, when GABA is involved in configuring of such circuit functioning. Provocatively a novel line of treatment is suggested (with a critical time window); by increasing neural GABA levels in children/adolescents with ASD, proper local circuitry maturation may be restored resulting in typical Gamma in adulthood. Autism Res 2017, 10: 593-607. © 2016 International Society for

  14. Hidden Hearing Loss and Computational Models of the Auditory Pathway: Predicting Speech Intelligibility Decline

    Science.gov (United States)

    2016-11-28

    Title: Hidden Hearing Loss and Computational Models of the Auditory Pathway: Predicting Speech Intelligibility Decline Christopher J. Smalt...representation of speech intelligibility in noise. The auditory-periphery model of Zilany et al. (JASA 2009,2014) is used to make predictions of...auditory nerve (AN) responses to speech stimuli under a variety of difficult listening conditions. The resulting cochlear neurogram, a spectrogram

  15. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  16. Word Recognition in Auditory Cortex

    Science.gov (United States)

    DeWitt, Iain D. J.

    2013-01-01

    Although spoken word recognition is more fundamental to human communication than text recognition, knowledge of word-processing in auditory cortex is comparatively impoverished. This dissertation synthesizes current models of auditory cortex, models of cortical pattern recognition, models of single-word reading, results in phonetics and results in…

  17. Central auditory neurons have composite receptive fields.

    Science.gov (United States)

    Kozlov, Andrei S; Gentner, Timothy Q

    2016-02-02

    High-level neurons processing complex, behaviorally relevant signals are sensitive to conjunctions of features. Characterizing the receptive fields of such neurons is difficult with standard statistical tools, however, and the principles governing their organization remain poorly understood. Here, we demonstrate multiple distinct receptive-field features in individual high-level auditory neurons in a songbird, European starling, in response to natural vocal signals (songs). We then show that receptive fields with similar characteristics can be reproduced by an unsupervised neural network trained to represent starling songs with a single learning rule that enforces sparseness and divisive normalization. We conclude that central auditory neurons have composite receptive fields that can arise through a combination of sparseness and normalization in neural circuits. Our results, along with descriptions of random, discontinuous receptive fields in the central olfactory neurons in mammals and insects, suggest general principles of neural computation across sensory systems and animal classes.

  18. Zwitterionic supramolecular nanoparticles: self-assembly and responsive properties

    NARCIS (Netherlands)

    Stoffelen, C.; Huskens, Jurriaan

    2015-01-01

    Supramolecular nanoparticles (SNPs) are of high interest in both nanoscience and molecular diagnostics and therapeutics, because of their reversible and designable properties. To ensure colloidal stabilization and biocompatibility, most reported strategies require the use of hydrophilic long-chain

  19. Peripheral Auditory Mechanisms

    CERN Document Server

    Hall, J; Hubbard, A; Neely, S; Tubis, A

    1986-01-01

    How weIl can we model experimental observations of the peripheral auditory system'? What theoretical predictions can we make that might be tested'? It was with these questions in mind that we organized the 1985 Mechanics of Hearing Workshop, to bring together auditory researchers to compare models with experimental observations. Tbe workshop forum was inspired by the very successful 1983 Mechanics of Hearing Workshop in Delft [1]. Boston University was chosen as the site of our meeting because of the Boston area's role as a center for hearing research in this country. We made a special effort at this meeting to attract students from around the world, because without students this field will not progress. Financial support for the workshop was provided in part by grant BNS- 8412878 from the National Science Foundation. Modeling is a traditional strategy in science and plays an important role in the scientific method. Models are the bridge between theory and experiment. Tbey test the assumptions made in experim...

  20. Mouse Panx1 Is Dispensable for Hearing Acquisition and Auditory Function.

    Science.gov (United States)

    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.

  1. Identification enhancement of auditory evoked potentials in EEG by epoch concatenation and temporal decorrelation.

    Science.gov (United States)

    Zavala-Fernandez, H; Orglmeister, R; Trahms, L; Sander, T H

    2012-12-01

    Event-related potentials (ERP) recorded by electroencephalography (EEG) are brain responses following an external stimulus, e.g., a sound or an image. They are used in fundamental cognitive research and neurological and psychiatric clinical research. ERPs are weaker than spontaneous brain activity and therefore it is difficult or even impossible to identify an ERP in the brain activity following an individual stimulus. For this reason, a blind source separation method relying on statistical information is proposed for the isolation of ERP after auditory stimulation. In this paper it is suggested to integrate epoch concatenation into the popular temporal decorrelation algorithm SOBI/TDSEP relying on time shifted correlations. With the proposed epoch concatenation temporal decorrelation (ecTD) algorithm a component representing the auditory evoked potential (AEP) is found in electroencephalographic data from an auditory stimulation experiment lasting 3min. The ecTD result is compared with the averaged AEP and it is superior to the result from the SOBI/TDSEP algorithm. Furthermore the ecTD processing leads to significant increases in the signal-to-noise ratio (shape SNR) of the AEP and reduces the computation time by 50% if compared to the SOBI/TDSEP calculation. It can be concluded that data concatenation in combination with temporal decorrelation is useful for isolating and improving the properties of an AEP especially in a short duration stimulation experiment. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  3. Neural correlates of auditory scale illusion.

    Science.gov (United States)

    Kuriki, Shinya; Numao, Ryousuke; Nemoto, Iku

    2016-09-01

    The auditory illusory perception "scale illusion" occurs when ascending and descending musical scale tones are delivered in a dichotic manner, such that the higher or lower tone at each instant is presented alternately to the right and left ears. Resulting tone sequences have a zigzag pitch in one ear and the reversed (zagzig) pitch in the other ear. Most listeners hear illusory smooth pitch sequences of up-down and down-up streams in the two ears separated in higher and lower halves of the scale. Although many behavioral studies have been conducted, how and where in the brain the illusory percept is formed have not been elucidated. In this study, we conducted functional magnetic resonance imaging using sequential tones that induced scale illusion (ILL) and those that mimicked the percept of scale illusion (PCP), and we compared the activation responses evoked by those stimuli by region-of-interest analysis. We examined the effects of adaptation, i.e., the attenuation of response that occurs when close-frequency sounds are repeated, which might interfere with the changes in activation by the illusion process. Results of the activation difference of the two stimuli, measured at varied tempi of tone presentation, in the superior temporal auditory cortex were not explained by adaptation. Instead, excess activation of the ILL stimulus from the PCP stimulus at moderate tempi (83 and 126 bpm) was significant in the posterior auditory cortex with rightward superiority, while significant prefrontal activation was dominant at the highest tempo (245 bpm). We suggest that the area of the planum temporale posterior to the primary auditory cortex is mainly involved in the illusion formation, and that the illusion-related process is strongly dependent on the rate of tone presentation. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Neuronal activity in primate auditory cortex during the performance of audiovisual tasks.

    Science.gov (United States)

    Brosch, Michael; Selezneva, Elena; Scheich, Henning

    2015-03-01

    This study aimed at a deeper understanding of which cognitive and motivational aspects of tasks affect auditory cortical activity. To this end we trained two macaque monkeys to perform two different tasks on the same audiovisual stimulus and to do this with two different sizes of water rewards. The monkeys had to touch a bar after a tone had been turned on together with an LED, and to hold the bar until either the tone (auditory task) or the LED (visual task) was turned off. In 399 multiunits recorded from core fields of auditory cortex we confirmed that during task engagement neurons responded to auditory and non-auditory stimuli that were task-relevant, such as light and water. We also confirmed that firing rates slowly increased or decreased for several seconds during various phases of the tasks. Responses to non-auditory stimuli and slow firing changes were observed during both the auditory and the visual task, with some differences between them. There was also a weak task-dependent modulation of the responses to auditory stimuli. In contrast to these cognitive aspects, motivational aspects of the tasks were not reflected in the firing, except during delivery of the water reward. In conclusion, the present study supports our previous proposal that there are two response types in the auditory cortex that represent the timing and the type of auditory and non-auditory elements of a auditory tasks as well the association between elements. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  5. [Communication and auditory behavior obtained by auditory evoked potentials in mammals, birds, amphibians, and reptiles].

    Science.gov (United States)

    Arch-Tirado, Emilio; Collado-Corona, Miguel Angel; Morales-Martínez, José de Jesús

    2004-01-01

    amphibians, Frog catesbiana (frog bull, 30 animals); reptiles, Sceloporus torcuatus (common small lizard, 22 animals); birds: Columba livia (common dove, 20 animals), and mammals, Cavia porcellus, (guinea pig, 20 animals). With regard to lodging, all animals were maintained at the Institute of Human Communication Disorders, were fed with special food for each species, and had water available ad libitum. Regarding procedure, for carrying out analysis of auditory evoked potentials of brain stem SPL amphibians, birds, and mammals were anesthetized with ketamine 20, 25, and 50 mg/kg, by injection. Reptiles were anesthetized by freezing (6 degrees C). Study subjects had needle electrodes placed in an imaginary line on the half sagittal line between both ears and eyes, behind right ear, and behind left ear. Stimulation was carried out inside a no noise site by means of a horn in free field. The sign was filtered at between 100 and 3,000 Hz and analyzed in a computer for provoked potentials (Racia APE 78). In data shown by amphibians, wave-evoked responses showed greater latency than those of the other species. In reptiles, latency was observed as reduced in comparison with amphibians. In the case of birds, lesser latency values were observed, while in the case of guinea pigs latencies were greater than those of doves but they were stimulated by 10 dB, which demonstrated best auditory threshold in the four studied species. Last, it was corroborated that as the auditory threshold of each species it descends conforms to it advances in the phylogenetic scale. Beginning with these registrations, we care able to say that response for evoked brain stem potential showed to be more complex and lesser values of absolute latency as we advance along the phylogenetic scale; thus, the opposing auditory threshold is better agreement with regard to the phylogenetic scale among studied species. These data indicated to us that seeking of auditory information is more complex in more

  6. Temporal factors affecting somatosensory-auditory interactions in speech processing

    Directory of Open Access Journals (Sweden)

    Takayuki eIto

    2014-11-01

    Full Text Available Speech perception is known to rely on both auditory and visual information. However, sound specific somatosensory input has been shown also to influence speech perceptual processing (Ito et al., 2009. In the present study we addressed further the relationship between somatosensory information and speech perceptual processing by addressing the hypothesis that the temporal relationship between orofacial movement and sound processing contributes to somatosensory-auditory interaction in speech perception. We examined the changes in event-related potentials in response to multisensory synchronous (simultaneous and asynchronous (90 ms lag and lead somatosensory and auditory stimulation compared to individual unisensory auditory and somatosensory stimulation alone. We used a robotic device to apply facial skin somatosensory deformations that were similar in timing and duration to those experienced in speech production. Following synchronous multisensory stimulation the amplitude of the event-related potential was reliably different from the two unisensory potentials. More importantly, the magnitude of the event-related potential difference varied as a function of the relative timing of the somatosensory-auditory stimulation. Event-related activity change due to stimulus timing was seen between 160-220 ms following somatosensory onset, mostly around the parietal area. The results demonstrate a dynamic modulation of somatosensory-auditory convergence and suggest the contribution of somatosensory information for speech processing process is dependent on the specific temporal order of sensory inputs in speech production.

  7. Primate auditory recognition memory performance varies with sound type.

    Science.gov (United States)

    Ng, Chi-Wing; Plakke, Bethany; Poremba, Amy

    2009-10-01

    Neural correlates of auditory processing, including for species-specific vocalizations that convey biological and ethological significance (e.g., social status, kinship, environment), have been identified in a wide variety of areas including the temporal and frontal cortices. However, few studies elucidate how non-human primates interact with these vocalization signals when they are challenged by tasks requiring auditory discrimination, recognition and/or memory. The present study employs a delayed matching-to-sample task with auditory stimuli to examine auditory memory performance of rhesus macaques (Macaca mulatta), wherein two sounds are determined to be the same or different. Rhesus macaques seem to have relatively poor short-term memory with auditory stimuli, and we examine if particular sound types are more favorable for memory performance. Experiment 1 suggests memory performance with vocalization sound types (particularly monkey), are significantly better than when using non-vocalization sound types, and male monkeys outperform female monkeys overall. Experiment 2, controlling for number of sound exemplars and presentation pairings across types, replicates Experiment 1, demonstrating better performance or decreased response latencies, depending on trial type, to species-specific monkey vocalizations. The findings cannot be explained by acoustic differences between monkey vocalizations and the other sound types, suggesting the biological, and/or ethological meaning of these sounds are more effective for auditory memory. 2009 Elsevier B.V.

  8. Auditory DUM neurons in a bush-cricket: A filter bank for carrier frequency.

    Science.gov (United States)

    Lefebvre, Paule Chloé; Seifert, Marvin; Stumpner, Andreas

    2018-05-01

    In bush-crickets the first stage of central auditory processing occurs in the prothoracic ganglion. About 15 to 50 different auditory dorsal unpaired median neurons (DUM neurons) exist but they have not been studied in any detail. These DUM neurons may be classified into seven different morphological types, although, there is only limited correlation between morphology and physiological responses. Ninety seven percent of the stained neurons were local, 3% were intersegmental. About 90% project nearly exclusively into the auditory neuropile, and 45% into restricted areas therein. Lateral extensions overlap with the axons of primary auditory sensory neurons close to their branching point. DUM neurons are typically tuned to frequencies covering the range between 2 and 50 kHz and thereby may establish a filter bank for carrier frequency. Less than 10% of DUM neurons have their branches in adjacent and more posterior regions of the auditory neuropile and are mostly tuned to low frequencies, less sensitive than the other types and respond to vibration. Thirty five percent of DUM show indications of inhibition, either through reduced responses at higher intensities, or by hyperpolarizing responses to sound. Most DUM neurons produce phasic spike responses preferably at higher intensities. Spikes may be elicited by intracellular current injection. Preliminary data suggest that auditory DUM neurons have GABA as transmitter and therefore may inhibit other auditory interneurons. From all known local auditory neurons, only DUM neurons have frequency specific responses which appear suited for local processing relevant for acoustic communication in bush crickets. © 2018 Wiley Periodicals, Inc.

  9. Sonic morphology: Aesthetic dimensional auditory spatial awareness

    Science.gov (United States)

    Whitehouse, Martha M.

    The sound and ceramic sculpture installation, " Skirting the Edge: Experiences in Sound & Form," is an integration of art and science demonstrating the concept of sonic morphology. "Sonic morphology" is herein defined as aesthetic three-dimensional auditory spatial awareness. The exhibition explicates my empirical phenomenal observations that sound has a three-dimensional form. Composed of ceramic sculptures that allude to different social and physical situations, coupled with sound compositions that enhance and create a three-dimensional auditory and visual aesthetic experience (see accompanying DVD), the exhibition supports the research question, "What is the relationship between sound and form?" Precisely how people aurally experience three-dimensional space involves an integration of spatial properties, auditory perception, individual history, and cultural mores. People also utilize environmental sound events as a guide in social situations and in remembering their personal history, as well as a guide in moving through space. Aesthetically, sound affects the fascination, meaning, and attention one has within a particular space. Sonic morphology brings art forms such as a movie, video, sound composition, and musical performance into the cognitive scope by generating meaning from the link between the visual and auditory senses. This research examined sonic morphology as an extension of musique concrete, sound as object, originating in Pierre Schaeffer's work in the 1940s. Pointing, as John Cage did, to the corporeal three-dimensional experience of "all sound," I composed works that took their total form only through the perceiver-participant's participation in the exhibition. While contemporary artist Alvin Lucier creates artworks that draw attention to making sound visible, "Skirting the Edge" engages the perceiver-participant visually and aurally, leading to recognition of sonic morphology.

  10. Auditory beat stimulation and its effects on cognition and mood states

    Directory of Open Access Journals (Sweden)

    Leila eChaieb

    2015-05-01

    Full Text Available Auditory beat stimulation may be a promising new tool for the manipulation of cognitive processes and the modulation of mood-states. Here we aim to review the literature examining the most current applications of auditory beat stimulation and its targets. We give a brief overview of research on auditory steady-state responses and its relationship to auditory beat stimulation. We have summarized relevant studies investigating the neurophysiological changes related to auditory beat stimulation and how they impact upon the design of appropriate stimulation protocols. Focusing on binaural beat stimulation, we then discuss the role of monaural and binaural beat frequencies in cognition and mood-states, in addition to their efficacy in targeting disease symptoms. We aim to highlight important points concerning stimulation parameters and try to address why there are often contradictory findings with regard to the outcomes of auditory beat stimulation.

  11. Aging increases distraction by auditory oddballs in visual, but not auditory tasks.

    Science.gov (United States)

    Leiva, Alicia; Parmentier, Fabrice B R; Andrés, Pilar

    2015-05-01

    Aging is typically considered to bring a reduction of the ability to resist distraction by task-irrelevant stimuli. Yet recent work suggests that this conclusion must be qualified and that the effect of aging is mitigated by whether irrelevant and target stimuli emanate from the same modalities or from distinct ones. Some studies suggest that aging is especially sensitive to distraction within-modality while others suggest it is greater across modalities. Here we report the first study to measure the effect of aging on deviance distraction in cross-modal (auditory-visual) and uni-modal (auditory-auditory) oddball tasks. Young and older adults were asked to judge the parity of target digits (auditory or visual in distinct blocks of trials), each preceded by a task-irrelevant sound (the same tone on most trials-the standard sound-or, on rare and unpredictable trials, a burst of white noise-the deviant sound). Deviant sounds yielded distraction (longer response times relative to standard sounds) in both tasks and age groups. However, an age-related increase in distraction was observed in the cross-modal task and not in the uni-modal task. We argue that aging might affect processes involved in the switching of attention across modalities and speculate that this may due to the slowing of this type of attentional shift or a reduction in cognitive control required to re-orient attention toward the target's modality.

  12. Developmental programming of auditory learning

    Directory of Open Access Journals (Sweden)

    Melania Puddu

    2012-10-01

    Full Text Available The basic structures involved in the development of auditory function and consequently in language acquisition are directed by genetic code, but the expression of individual genes may be altered by exposure to environmental factors, which if favorable, orient it in the proper direction, leading its development towards normality, if unfavorable, they deviate it from its physiological course. Early sensorial experience during the foetal period (i.e. intrauterine noise floor, sounds coming from the outside and attenuated by the uterine filter, particularly mother’s voice and modifications induced by it at the cochlear level represent the first example of programming in one of the earliest critical periods in development of the auditory system. This review will examine the factors that influence the developmental programming of auditory learning from the womb to the infancy. In particular it focuses on the following points: the prenatal auditory experience and the plastic phenomena presumably induced by it in the auditory system from the basilar membrane to the cortex;the involvement of these phenomena on language acquisition and on the perception of language communicative intention after birth;the consequences of auditory deprivation in critical periods of auditory development (i.e. premature interruption of foetal life.

  13. Marsh Soil Responses to Nutrients: Belowground Structural and Organic Properties.

    Science.gov (United States)

    Coastal marsh responses to nutrient enrichment apparently depend upon soil matrix and whether the system is primarily biogenic or minerogenic. Deteriorating organic rich marshes (Jamaica Bay, NY) receiving wastewater effluent had lower belowground biomass, organic matter, and soi...

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Aging Affects Adaptation to Sound-Level Statistics in Human Auditory Cortex.

    Science.gov (United States)

    Herrmann, Björn; Maess, Burkhard; Johnsrude, Ingrid S

    2018-02-21

    Optimal perception requires efficient and adaptive neural processing of sensory input. Neurons in nonhuman mammals adapt to the statistical properties of acoustic feature distributions such that they become sensitive to sounds that are most likely to occur in the environment. However, whether human auditory responses adapt to stimulus statistical distributions and how aging affects adaptation to stimulus statistics is unknown. We used MEG to study how exposure to different distributions of sound levels affects adaptation in auditory cortex of younger (mean: 25 years; n = 19) and older (mean: 64 years; n = 20) adults (male and female). Participants passively listened to two sound-level distributions with different modes (either 15 or 45 dB sensation level). In a control block with long interstimulus intervals, allowing neural populations to recover from adaptation, neural response magnitudes were similar between younger and older adults. Critically, both age groups demonstrated adaptation to sound-level stimulus statistics, but adaptation was altered for older compared with younger people: in the older group, neural responses continued to be sensitive to sound level under conditions in which responses were fully adapted in the younger group. The lack of full adaptation to the statistics of the sensory environment may be a physiological mechanism underlying the known difficulty that older adults have with filtering out irrelevant sensory information. SIGNIFICANCE STATEMENT Behavior requires efficient processing of acoustic stimulation. Animal work suggests that neurons accomplish efficient processing by adjusting their response sensitivity depending on statistical properties of the acoustic environment. Little is known about the extent to which this adaptation to stimulus statistics generalizes to humans, particularly to older humans. We used MEG to investigate how aging influences adaptation to sound-level statistics. Listeners were presented with sounds drawn from

  16. Binaural processing by the gecko auditory periphery.

    Science.gov (United States)

    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.

  17. Hierarchical processing of auditory objects in humans.

    Directory of Open Access Journals (Sweden)

    Sukhbinder Kumar

    2007-06-01

    Full Text Available This work examines the computational architecture used by the brain during the analysis of the spectral envelope of sounds, an important acoustic feature for defining auditory objects. Dynamic causal modelling and Bayesian model selection were used to evaluate a family of 16 network models explaining functional magnetic resonance imaging responses in the right temporal lobe during spectral envelope analysis. The models encode different hypotheses about the effective connectivity between Heschl's Gyrus (HG, containing the primary auditory cortex, planum temporale (PT, and superior temporal sulcus (STS, and the modulation of that coupling during spectral envelope analysis. In particular, we aimed to determine whether information processing during spectral envelope analysis takes place in a serial or parallel fashion. The analysis provides strong support for a serial architecture with connections from HG to PT and from PT to STS and an increase of the HG to PT connection during spectral envelope analysis. The work supports a computational model of auditory object processing, based on the abstraction of spectro-temporal "templates" in the PT before further analysis of the abstracted form in anterior temporal lobe areas.

  18. The effects of auditory enrichment on gorillas.

    Science.gov (United States)

    Robbins, Lindsey; Margulis, Susan W

    2014-01-01

    Several studies have demonstrated that auditory enrichment can reduce stereotypic behaviors in captive animals. The purpose of this study was to determine the relative effectiveness of three different types of auditory enrichment-naturalistic sounds, classical music, and rock music-in reducing stereotypic behavior displayed by Western lowland gorillas (Gorilla gorilla gorilla). Three gorillas (one adult male, two adult females) were observed at the Buffalo Zoo for a total of 24 hr per music trial. A control observation period, during which no sounds were presented, was also included. Each music trial consisted of a total of three weeks with a 1-week control period in between each music type. The results reveal a decrease in stereotypic behaviors from the control period to naturalistic sounds. The naturalistic sounds also affected patterns of several other behaviors including locomotion. In contrast, stereotypy increased in the presence of classical and rock music. These results suggest that auditory enrichment, which is not commonly used in zoos in a systematic way, can be easily utilized by keepers to help decrease stereotypic behavior, but the nature of the stimulus, as well as the differential responses of individual animals, need to be considered. © 2014 Wiley Periodicals, Inc.

  19. Auditory short-term memory in the primate auditory cortex

    OpenAIRE

    Scott, Brian H.; Mishkin, Mortimer

    2015-01-01

    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 sho...

  20. The auditory-evoked N2 and P3 components in the stop-signal task: indices of inhibition, response-conflict or error-detection?

    Science.gov (United States)

    Dimoska, Aneta; Johnstone, Stuart J; Barry, Robert J

    2006-11-01

    The N2 and P3 components have been separately associated with response inhibition in the stop-signal task, and more recently, the N2 has been implicated in the detection of response-conflict. To isolate response inhibition activity from early sensory processing, the present study compared processing of the stop-signal with that of a task-irrelevant tone, which subjects were instructed to ignore. Stop-signals elicited a larger N2 on failed-stop trials and a larger P3 on successful-stop trials, relative to ignore-signal trials, likely reflecting activity related to failed and successful stopping, respectively. ERPs between fast and slow reaction-time (RT) groups were also examined as it was hypothesised that greater inhibitory activation to stop faster responses would manifest in the component reflecting this process. Successful-stop P3 showed the anticipated effect (globally larger amplitude in the fast than slow RT group), supporting its association with the stopping of an ongoing response. In contrast, N2 was larger in the slow than fast RT group, and in contrast to the predictions of the response-conflict hypothesis, successful-stop N2 and the response-locked error-negativity (Ne) differed in scalp distribution. These findings indicate that the successful-stop N2 may be better explained as a deliberate form of response control or selection, which the slow RT group employed as a means of increasing the likelihood of a successful-stop. Finally, a comparison of stimulus and response-locked ERPs revealed that the failed-stop N2 and P3 appeared to reflect error-related activity, best observed in the response-locked Ne and error-positivity (Pe). Together these findings indicate that the successful-stop N2 and P3 reflect functionally distinct aspects of response control that are dependent upon performance strategies, while failed-stop N2 and P3 reflect error-related activity.

  1. Spike latency and response properties of an excitable micropillar laser

    Science.gov (United States)

    Selmi, F.; Braive, R.; Beaudoin, G.; Sagnes, I.; Kuszelewicz, R.; Erneux, T.; Barbay, S.

    2016-10-01

    We present experimental measurements concerning the response of an excitable micropillar laser with saturable absorber to incoherent as well as coherent perturbations. The excitable response is similar to the behavior of spiking neurons but with much faster time scales. It is accompanied by a subnanosecond nonlinear delay that is measured for different bias pump values. This mechanism provides a natural scheme for encoding the strength of an ultrafast stimulus in the response delay of excitable spikes (temporal coding). Moreover, we demonstrate coherent and incoherent perturbations techniques applied to the micropillar with perturbation thresholds in the range of a few femtojoules. Responses to coherent perturbations assess the cascadability of the system. We discuss the physical origin of the responses to single and double perturbations with the help of numerical simulations of the Yamada model and, in particular, unveil possibilities to control the relative refractory period that we recently evidenced in this system. Experimental measurements are compared to both numerical simulations of the Yamada model and analytic expressions obtained in the framework of singular perturbation techniques. This system is thus a good candidate to perform photonic spike processing tasks in the framework of novel neuroinspired computing systems.

  2. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans

    Science.gov (United States)

    Hattori, Yuko; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2015-01-01

    Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum) and auditory rhythms (e.g., hearing music while walking). Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse), suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement. PMID:26132703

  3. Electrophysiological Evidence of Developmental Changes in the Duration of Auditory Sensory Memory.

    Science.gov (United States)

    Gomes, Hilary; And Others

    1999-01-01

    Investigated developmental change in duration of auditory sensory memory for tonal frequency by measuring mismatch negativity, an electrophysiological component of the auditory event-related potential that is relatively insensitive to attention and does not require a behavioral response. Findings among children and adults suggest that there are…

  4. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans.

    Directory of Open Access Journals (Sweden)

    Yuko Hattori

    Full Text Available Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum and auditory rhythms (e.g., hearing music while walking. Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse, suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement.

  5. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans.

    Science.gov (United States)

    Hattori, Yuko; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2015-01-01

    Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum) and auditory rhythms (e.g., hearing music while walking). Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse), suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement.

  6. Using Facebook to Reach People Who Experience Auditory Hallucinations.

    Science.gov (United States)

    Crosier, Benjamin Sage; Brian, Rachel Marie; Ben-Zeev, Dror

    2016-06-14

    Auditory hallucinations (eg, hearing voices) are relatively common and underreported false sensory experiences that may produce distress and impairment. A large proportion of those who experience auditory hallucinations go unidentified and untreated. Traditional engagement methods oftentimes fall short in reaching the diverse population of people who experience auditory hallucinations. The objective of this proof-of-concept study was to examine the viability of leveraging Web-based social media as a method of engaging people who experience auditory hallucinations and to evaluate their attitudes toward using social media platforms as a resource for Web-based support and technology-based treatment. We used Facebook advertisements to recruit individuals who experience auditory hallucinations to complete an 18-item Web-based survey focused on issues related to auditory hallucinations and technology use in American adults. We systematically tested multiple elements of the advertisement and survey layout including image selection, survey pagination, question ordering, and advertising targeting strategy. Each element was evaluated sequentially and the most cost-effective strategy was implemented in the subsequent steps, eventually deriving an optimized approach. Three open-ended question responses were analyzed using conventional inductive content analysis. Coded responses were quantified into binary codes, and frequencies were then calculated. Recruitment netted N=264 total sample over a 6-week period. Ninety-seven participants fully completed all measures at a total cost of $8.14 per participant across testing phases. Systematic adjustments to advertisement design, survey layout, and targeting strategies improved data quality and cost efficiency. People were willing to provide information on what triggered their auditory hallucinations along with strategies they use to cope, as well as provide suggestions to others who experience auditory hallucinations. Women, people

  7. Using Facebook to Reach People Who Experience Auditory Hallucinations

    Science.gov (United States)

    Brian, Rachel Marie; Ben-Zeev, Dror

    2016-01-01

    Background Auditory hallucinations (eg, hearing voices) are relatively common and underreported false sensory experiences that may produce distress and impairment. A large proportion of those who experience auditory hallucinations go unidentified and untreated. Traditional engagement methods oftentimes fall short in reaching the diverse population of people who experience auditory hallucinations. Objective The objective of this proof-of-concept study was to examine the viability of leveraging Web-based social media as a method of engaging people who experience auditory hallucinations and to evaluate their attitudes toward using social media platforms as a resource for Web-based support and technology-based treatment. Methods We used Facebook advertisements to recruit individuals who experience auditory hallucinations to complete an 18-item Web-based survey focused on issues related to auditory hallucinations and technology use in American adults. We systematically tested multiple elements of the advertisement and survey layout including image selection, survey pagination, question ordering, and advertising targeting strategy. Each element was evaluated sequentially and the most cost-effective strategy was implemented in the subsequent steps, eventually deriving an optimized approach. Three open-ended question responses were analyzed using conventional inductive content analysis. Coded responses were quantified into binary codes, and frequencies were then calculated. Results Recruitment netted N=264 total sample over a 6-week period. Ninety-seven participants fully completed all measures at a total cost of $8.14 per participant across testing phases. Systematic adjustments to advertisement design, survey layout, and targeting strategies improved data quality and cost efficiency. People were willing to provide information on what triggered their auditory hallucinations along with strategies they use to cope, as well as provide suggestions to others who experience

  8. Leftward lateralization of auditory cortex underlies holistic sound perception in Williams syndrome.

    Science.gov (United States)

    Wengenroth, Martina; Blatow, Maria; Bendszus, Martin; Schneider, Peter

    2010-08-23

    Individuals with the rare genetic disorder Williams-Beuren syndrome (WS) are known for their characteristic auditory phenotype including strong affinity to music and sounds. In this work we attempted to pinpoint a neural substrate for the characteristic musicality in WS individuals by studying the structure-function relationship of their auditory cortex. Since WS subjects had only minor musical training due to psychomotor constraints we hypothesized that any changes compared to the control group would reflect the contribution of genetic factors to auditory processing and musicality. Using psychoacoustics, magnetoencephalography and magnetic resonance imaging, we show that WS individuals exhibit extreme and almost exclusive holistic sound perception, which stands in marked contrast to the even distribution of this trait in the general population. Functionally, this was reflected by increased amplitudes of left auditory evoked fields. On the structural level, volume of the left auditory cortex was 2.2-fold increased in WS subjects as compared to control subjects. Equivalent volumes of the auditory cortex have been previously reported for professional musicians. There has been an ongoing debate in the neuroscience community as to whether increased gray matter of the auditory cortex in musicians is attributable to the amount of training or innate disposition. In this study musical education of WS subjects was negligible and control subjects were carefully matched for this parameter. Therefore our results not only unravel the neural substrate for this particular auditory phenotype, but in addition propose WS as a unique genetic model for training-independent auditory system properties.

  9. Hierarchical auditory processing directed rostrally along the monkey's supratemporal plane.

    Science.gov (United States)

    Kikuchi, Yukiko; Horwitz, Barry; Mishkin, Mortimer

    2010-09-29

    Connectional anatomical evidence suggests that the auditory core, containing the tonotopic areas A1, R, and RT, constitutes the first stage of auditory cortical processing, with feedforward projections from core outward, first to the surrounding auditory belt and then to the parabelt. Connectional evidence also raises the possibility that the core itself is serially organized, with feedforward projections from A1 to R and with additional projections, although of unknown feed direction, from R to RT. We hypothesized that area RT together with more rostral parts of the supratemporal plane (rSTP) form the anterior extension of a rostrally directed stimulus quality processing stream originating in the auditory core area A1. Here, we analyzed auditory responses of single neurons in three different sectors distributed caudorostrally along the supratemporal plane (STP): sector I, mainly area A1; sector II, mainly area RT; and sector III, principally RTp (the rostrotemporal polar area), including cortex located 3 mm from the temporal tip. Mean onset latency of excitation responses and stimulus selectivity to monkey calls and other sounds, both simple and complex, increased progressively from sector I to III. Also, whereas cells in sector I responded with significantly higher firing rates to the "other" sounds than to monkey calls, those in sectors II and III responded at the same rate to both stimulus types. The pattern of results supports the proposal that the STP contains a rostrally directed, hierarchically organized auditory processing stream, with gradually increasing stimulus selectivity, and that this stream extends from the primary auditory area to the temporal pole.

  10. Left auditory cortex gamma synchronization and auditory hallucination symptoms in schizophrenia

    Directory of Open Access Journals (Sweden)

    Shenton Martha E

    2009-07-01

    Full Text Available Abstract Background Oscillatory electroencephalogram (EEG abnormalities may reflect neural circuit dysfunction in neuropsychiatric disorders. Previously we have found positive correlations between the phase synchronization of beta and gamma oscillations and hallucination symptoms in schizophrenia patients. These findings suggest that the propensity for hallucinations is associated with an increased tendency for neural circuits in sensory cortex to enter states of oscillatory synchrony. Here we tested this hypothesis by examining whether the 40 Hz auditory steady-state response (ASSR generated in the left primary auditory cortex is positively correlated with auditory hallucination symptoms in schizophrenia. We also examined whether the 40 Hz ASSR deficit in schizophrenia was associated with cross-frequency interactions. Sixteen healthy control subjects (HC and 18 chronic schizophrenia patients (SZ listened to 40 Hz binaural click trains. The EEG was recorded from 60 electrodes and average-referenced offline. A 5-dipole model was fit from the HC grand average ASSR, with 2 pairs of superior temporal dipoles and a deep midline dipole. Time-frequency decomposition was performed on the scalp EEG and source data. Results Phase locking factor (PLF and evoked power were reduced in SZ at fronto-central electrodes, replicating prior findings. PLF was reduced in SZ for non-homologous right and left hemisphere sources. Left hemisphere source PLF in SZ was positively correlated with auditory hallucination symptoms, and was modulated by delta phase. Furthermore, the correlations between source evoked power and PLF found in HC was reduced in SZ for the LH sources. Conclusion These findings suggest that differential neural circuit abnormalities may be present in the left and right auditory cortices in schizophrenia. In addition, they provide further support for the hypothesis that hallucinations are related to cortical hyperexcitability, which is manifested by

  11. Atypical auditory refractory periods in children from lower socio-economic status backgrounds: ERP evidence for a role of selective attention.

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    Stevens, Courtney; Paulsen, David; Yasen, Alia; Neville, Helen

    2015-02-01

    Previous neuroimaging studies indicate that lower socio-economic status (SES) is associated with reduced effects of selective attention on auditory processing. Here, we investigated whether lower SES is also associated with differences in a stimulus-driven aspect of auditory processing: the neural refractory period, or reduced amplitude response at faster rates of stimulus presentation. Thirty-two children aged 3 to 8 years participated, and were divided into two SES groups based on maternal education. Event-related brain potentials were recorded to probe stimuli presented at interstimulus intervals (ISIs) of 200, 500, or 1000 ms. These probes were superimposed on story narratives when attended and ignored, permitting a simultaneous experimental manipulation of selective attention. Results indicated that group differences in refractory periods differed as a function of attention condition. Children from higher SES backgrounds showed full neural recovery by 500 ms for attended stimuli, but required at least 1000 ms for unattended stimuli. In contrast, children from lower SES backgrounds showed similar refractory effects to attended and unattended stimuli, with full neural recovery by 500 ms. Thus, in higher SES children only, one functional consequence of selective attention is attenuation of the response to unattended stimuli, particularly at rapid ISIs, altering basic properties of the auditory refractory period. Together, these data indicate that differences in selective attention impact basic aspects of auditory processing in children from lower SES backgrounds. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Demodulation Processes in Auditory Perception

    National Research Council Canada - National Science Library

    Feth, Lawrence

    1997-01-01

    The long range goal of this project was the understanding of human auditory processing of information conveyed by complex, time varying signals such as speech, music or important environmental sounds...

  13. Auditory and Visual Electrophysiology of Deaf Children with Cochlear Implants: Implications for Cross-modal Plasticity.

    Science.gov (United States)

    Corina, David P; Blau, Shane; LaMarr, Todd; Lawyer, Laurel A; Coffey-Corina, Sharon

    2017-01-01

    Deaf children who receive a cochlear implant early in life and engage in intensive oral/aural therapy often make great strides in spoken language acquisition. However, despite clinicians' best efforts, there is a great deal of variability in language outcomes. One concern is that cortical regions which normally support auditory processing may become reorganized for visual function, leaving fewer available resources for auditory language acquisition. The conditions under which these changes occur are not well understood, but we may begin investigating this phenomenon by looking for interactions between auditory and visual evoked cortical potentials in deaf children. If children with abnormal auditory responses show increased sensitivity to visual stimuli, this may indicate the presence of maladaptive cortical plasticity. We recorded evoked potentials, using both auditory and visual paradigms, from 25 typical hearing children and 26 deaf children (ages 2-8 years) with cochlear implants. An auditory oddball paradigm was used (85% /ba/ syllables vs. 15% frequency modulated tone sweeps) to elicit an auditory P1 component. Visual evoked potentials (VEPs) were recorded during presentation of an intermittent peripheral radial checkerboard while children watched a silent cartoon, eliciting a P1-N1 response. We observed reduced auditory P1 amplitudes and a lack of latency shift associated with normative aging in our deaf sample. We also observed shorter latencies in N1 VEPs to visual stimulus offset in deaf participants. While these data demonstrate cortical changes associated with auditory deprivation, we did not find evidence for a relationship between cortical auditory evoked potentials and the VEPs. This is consistent with descriptions of intra-modal plasticity within visual systems of deaf children, but do not provide evidence for cross-modal plasticity. In addition, we note that sign language experience had no effect on deaf children's early auditory and visual ERP

  14. Increased Early Processing of Task-Irrelevant