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Sample records for auditory forebrain frequency

  1. Hierarchical emergence of sequence sensitivity in the songbird auditory forebrain.

    Science.gov (United States)

    Ono, Satoko; Okanoya, Kazuo; Seki, Yoshimasa

    2016-03-01

    Bengalese finches (Lonchura striata var. domestica) generate more complex sequences in their songs than zebra finches. Because of this, we chose this species to explore the signal processing of sound sequence in the primary auditory forebrain area, field L, and in a secondary area, the caudomedial nidopallium (NCM). We simultaneously recorded activity from multiple single units in urethane-anesthetized birds. We successfully replicated the results of a previous study in awake zebra finches examining stimulus-specific habituation of NCM neurons to conspecific songs. Then, we used an oddball paradigm and compared the neural response to deviant sounds that were presented infrequently, with the response to standard sounds, which were presented frequently. In a single sound oddball task, two different song elements were assigned for the deviant and standard sounds. The response bias to deviant elements was larger in NCM than in field L. In a triplet sequence oddball task, two triplet sequences containing elements ABC and ACB were assigned as the deviant and standard. Only neurons in NCM that displayed broad-shaped spike waveforms had sensitivity to the difference in element order. Our results suggest the hierarchical processing of complex sound sequences in the songbird auditory forebrain. PMID:26864094

  2. Toward a neurobiology of auditory object perception: What can we learn from the songbird forebrain?

    Institute of Scientific and Technical Information of China (English)

    Kai LU; David S. VICARIO

    2011-01-01

    In the acoustic world,no sounds occur entirely in isolation; they always reach the ears in combination with other sounds.How any given sound is discriminated and perceived as an independent auditory object is a challenging question in neuroscience.Although our knowledge of neural processing in the auditory pathway has expanded over the years,no good theory exists to explain how perception of auditory objects is achieved.A growing body of evidence suggests that the selectivity of neurons in the auditory forebrain is under dynamic modulation,and this plasticity may contribute to auditory object perception.We propose that stimulus-specific adaptation in the auditory forebrain of the songbird (and perhaps in other systems) may play an important role in modulating sensitivity in a way that aids discrimination,and thus can potentially contribute to auditory object perception [Current Zoology 57 (6):671-683,2011].

  3. Toward a neurobiology of auditory object perception: What can we learn from the songbird forebrain?

    Directory of Open Access Journals (Sweden)

    Kai LU, David S. VICARIO

    2011-12-01

    Full Text Available In the acoustic world, no sounds occur entirely in isolation; they always reach the ears in combination with other sounds. How any given sound is discriminated and perceived as an independent auditory object is a challenging question in neuroscience. Although our knowledge of neural processing in the auditory pathway has expanded over the years, no good theory exists to explain how perception of auditory objects is achieved. A growing body of evidence suggests that the selectivity of neurons in the auditory forebrain is under dynamic modulation, and this plasticity may contribute to auditory object perception. We propose that stimulus-specific adaptation in the auditory forebrain of the songbird (and perhaps in other systems may play an important role in modulating sensitivity in a way that aids discrimination, and thus can potentially contribute to auditory object perception [Current Zoology 57 (6: 671–683, 2011].

  4. A songbird forebrain area potentially involved in auditory discrimination and memory formation

    Indian Academy of Sciences (India)

    Raphael Pinaud; Thomas A Terleph

    2008-03-01

    Songbirds rely on auditory processing of natural communication signals for a number of social behaviors, including mate selection, individual recognition and the rare behavior of vocal learning – the ability to learn vocalizations through imitation of an adult model, rather than by instinct. Like mammals, songbirds possess a set of interconnected ascending and descending auditory brain pathways that process acoustic information and that are presumably involved in the perceptual processing of vocal communication signals. Most auditory areas studied to date are located in the caudomedial forebrain of the songbird and include the thalamo-recipient field L (subfields L1, L2 and L3), the caudomedial and caudolateral mesopallium (CMM and CLM, respectively) and the caudomedial nidopallium (NCM). This review focuses on NCM, an auditory area previously proposed to be analogous to parts of the primary auditory cortex in mammals. Stimulation of songbirds with auditory stimuli drives vigorous electrophysiological responses and the expression of several activity-regulated genes in NCM. Interestingly, NCM neurons are tuned to species-specific songs and undergo some forms of experience-dependent plasticity in-vivo. These activity-dependent changes may underlie long-term modifications in the functional performance of NCM and constitute a potential neural substrate for auditory discrimination. We end this review by discussing evidence that suggests that NCM may be a site of auditory memory formation and/or storage.

  5. The Basal Forebrain and Motor Cortex Provide Convergent yet Distinct Movement-Related Inputs to the Auditory Cortex.

    Science.gov (United States)

    Nelson, Anders; Mooney, Richard

    2016-05-01

    Cholinergic inputs to the auditory cortex from the basal forebrain (BF) are important to auditory processing and plasticity, but little is known about the organization of these synapses onto different auditory cortical neuron types, how they influence auditory responsiveness, and their activity patterns during various behaviors. Using intersectional tracing, optogenetic circuit mapping, and in vivo calcium imaging, we found that cholinergic axons arising from the caudal BF target major excitatory and inhibitory auditory cortical cell types, rapidly modulate auditory cortical tuning, and display fast movement-related activity. Furthermore, the BF and the motor cortex-another source of movement-related activity-provide convergent input onto some of the same auditory cortical neurons. Cholinergic and motor cortical afferents to the auditory cortex display distinct activity patterns and presynaptic partners, indicating that the auditory cortex integrates bottom-up cholinergic signals related to ongoing movements and arousal with top-down information concerning impending movements and motor planning. PMID:27112494

  6. Song exposure regulates known and novel microRNAs in the zebra finch auditory forebrain

    Directory of Open Access Journals (Sweden)

    Kim Jong H

    2011-05-01

    Full Text Available Abstract Background In an important model for neuroscience, songbirds learn to discriminate songs they hear during tape-recorded playbacks, as demonstrated by song-specific habituation of both behavioral and neurogenomic responses in the auditory forebrain. We hypothesized that microRNAs (miRNAs or miRs may participate in the changing pattern of gene expression induced by song exposure. To test this, we used massively parallel Illumina sequencing to analyse small RNAs from auditory forebrain of adult zebra finches exposed to tape-recorded birdsong or silence. Results In the auditory forebrain, we identified 121 known miRNAs conserved in other vertebrates. We also identified 34 novel miRNAs that do not align to human or chicken genomes. Five conserved miRNAs showed significant and consistent changes in copy number after song exposure across three biological replications of the song-silence comparison, with two increasing (tgu-miR-25, tgu-miR-192 and three decreasing (tgu-miR-92, tgu-miR-124, tgu-miR-129-5p. We also detected a locus on the Z sex chromosome that produces three different novel miRNAs, with supporting evidence from Northern blot and TaqMan qPCR assays for differential expression in males and females and in response to song playbacks. One of these, tgu-miR-2954-3p, is predicted (by TargetScan to regulate eight song-responsive mRNAs that all have functions in cellular proliferation and neuronal differentiation. Conclusions The experience of hearing another bird singing alters the profile of miRNAs in the auditory forebrain of zebra finches. The response involves both known conserved miRNAs and novel miRNAs described so far only in the zebra finch, including a novel sex-linked, song-responsive miRNA. These results indicate that miRNAs are likely to contribute to the unique behavioural biology of learned song communication in songbirds.

  7. Auditory filters at low-frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Pedersen, Christian Sejer; Møller, Henrik

    2009-01-01

    Prediction and assessment of low-frequency noise problems requires information about the auditory filter characteristics at low-frequencies. Unfortunately, data at low-frequencies is scarce and practically no results have been published for frequencies below 100 Hz. Extrapolation of ERB results...... from previous studies suggests the filter bandwidth keeps decreasing below 100 Hz, although at a relatively lower rate than at higher frequencies. Main characteristics of the auditory filter were studied from below 100 Hz up to 1000 Hz. Center frequencies evaluated were 50, 63, 125, 250, 500, and 1000......-ear transfer function), the asymmetry of the auditory filter changed from steeper high-frequency slopes at 1000 Hz to steeper low-frequency slopes below 100 Hz. Increasing steepness at low-frequencies of the middle-ear high-pass filter is thought to cause this effect. The dynamic range of the auditory filter...

  8. Encoding frequency contrast in primate auditory cortex

    OpenAIRE

    Malone, Brian J.; Scott, Brian H.; Semple, Malcolm N.

    2014-01-01

    Changes in amplitude and frequency jointly determine much of the communicative significance of complex acoustic signals, including human speech. We have previously described responses of neurons in the core auditory cortex of awake rhesus macaques to sinusoidal amplitude modulation (SAM) signals. Here we report a complementary study of sinusoidal frequency modulation (SFM) in the same neurons. Responses to SFM were analogous to SAM responses in that changes in multiple parameters defining SFM...

  9. Differential maturation of vesicular glutamate and GABA transporter expression in the mouse auditory forebrain during the first weeks of hearing.

    Science.gov (United States)

    Hackett, Troy A; Clause, Amanda R; Takahata, Toru; Hackett, Nicholas J; Polley, Daniel B

    2016-06-01

    Vesicular transporter proteins are an essential component of the presynaptic machinery that regulates neurotransmitter storage and release. They also provide a key point of control for homeostatic signaling pathways that maintain balanced excitation and inhibition following changes in activity levels, including the onset of sensory experience. To advance understanding of their roles in the developing auditory forebrain, we tracked the expression of the vesicular transporters of glutamate (VGluT1, VGluT2) and GABA (VGAT) in primary auditory cortex (A1) and medial geniculate body (MGB) of developing mice (P7, P11, P14, P21, adult) before and after ear canal opening (~P11-P13). RNA sequencing, in situ hybridization, and immunohistochemistry were combined to track changes in transporter expression and document regional patterns of transcript and protein localization. Overall, vesicular transporter expression changed the most between P7 and P21. The expression patterns and maturational trajectories of each marker varied by brain region, cortical layer, and MGB subdivision. VGluT1 expression was highest in A1, moderate in MGB, and increased with age in both regions. VGluT2 mRNA levels were low in A1 at all ages, but high in MGB, where adult levels were reached by P14. VGluT2 immunoreactivity was prominent in both regions. VGluT1 (+) and VGluT2 (+) transcripts were co-expressed in MGB and A1 somata, but co-localization of immunoreactive puncta was not detected. In A1, VGAT mRNA levels were relatively stable from P7 to adult, while immunoreactivity increased steadily. VGAT (+) transcripts were rare in MGB neurons, whereas VGAT immunoreactivity was robust at all ages. Morphological changes in immunoreactive puncta were found in two regions after ear canal opening. In the ventral MGB, a decrease in VGluT2 puncta density was accompanied by an increase in puncta size. In A1, perisomatic VGAT and VGluT1 terminals became prominent around the neuronal somata. Overall, the

  10. Control of phasic firing by a background leak current in avian forebrain auditory neurons

    Directory of Open Access Journals (Sweden)

    Andre Andreotti Dagostin

    2015-12-01

    Full Text Available Central neurons express a variety of neuronal types and ion channels that promote firing heterogeneity among their distinct neuronal populations. Action potential (AP phasic firing, produced by low-threshold voltage activated potassium currents (VAKCs, is commonly observed in mammalian brainstem neurons involved in the processing of temporal properties of the acoustic information. The avian caudomedial nidopallium (NCM is an auditory area analogous to portions of the mammalian auditory cortex that is involved in the perceptual discrimination and memorization of birdsong and shows complex responses to auditory stimuli We performed in vitro whole-cell patch-clamp recordings in brain slices from adult zebra finches (Taeniopygia guttata and observed that half of NCM neurons fire APs phasically in response to membrane depolarizations, while the rest fire transiently or tonically. Phasic neurons fired APs faster and with more temporal precision than tonic and transient neurons. These neurons had similar membrane resting potentials, but phasic neurons had lower membrane input resistance and time constant. Surprisingly phasic neurons did not express low-threshold VAKCs, which curtailed firing in phasic mammalian brainstem neurons, having similar VAKCs than the other NCM neurons. The phasic firing was determined not by VAKCs, but by the potassium background leak conductances, which was more prominently expressed in phasic neurons, a result corroborated by pharmacological, dynamic-clamp and modeling experiments. These results reveal a new role for leak currents in generating firing diversity in central neurons.

  11. Control of Phasic Firing by a Background Leak Current in Avian Forebrain Auditory Neurons.

    Science.gov (United States)

    Dagostin, André A; Lovell, Peter V; Hilscher, Markus M; Mello, Claudio V; Leão, Ricardo M

    2015-01-01

    Central neurons express a variety of neuronal types and ion channels that promote firing heterogeneity among their distinct neuronal populations. Action potential (AP) phasic firing, produced by low-threshold voltage-activated potassium currents (VAKCs), is commonly observed in mammalian brainstem neurons involved in the processing of temporal properties of the acoustic information. The avian caudomedial nidopallium (NCM) is an auditory area analogous to portions of the mammalian auditory cortex that is involved in the perceptual discrimination and memorization of birdsong and shows complex responses to auditory stimuli We performed in vitro whole-cell patch-clamp recordings in brain slices from adult zebra finches (Taeniopygia guttata) and observed that half of NCM neurons fire APs phasically in response to membrane depolarizations, while the rest fire transiently or tonically. Phasic neurons fired APs faster and with more temporal precision than tonic and transient neurons. These neurons had similar membrane resting potentials, but phasic neurons had lower membrane input resistance and time constant. Surprisingly phasic neurons did not express low-threshold VAKCs, which curtailed firing in phasic mammalian brainstem neurons, having similar VAKCs to other NCM neurons. The phasic firing was determined not by VAKCs, but by the potassium background leak conductances, which was more prominently expressed in phasic neurons, a result corroborated by pharmacological, dynamic-clamp, and modeling experiments. These results reveal a new role for leak currents in generating firing diversity in central neurons. PMID:26696830

  12. Auditory place theory and frequency difference limen

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jialu

    2006-01-01

    It has been a barrier that the place code is far too coarse a mechanism to account for the finest frequency difference limen for place theory of hearing since it was proposed in 19th century. A place correlation model, which takes the energy distribution of a pure tone in neighboring bands of auditory filters into full account, was presented in this paper. The model based on the place theory and some experimental results of the psychophysical tuning curves of hearing can explain the finest difference limen for frequency (about 0.02 or 0.3% at 1000 Hz)easily. Using a standard 1/3 octave filter bank of which the relationship between the frequency of a input pure tone apart from the centre frequency of K-th filter band, △f, and the output intensity difference between K-th and (K + 1)-th filters, △E, was established in order to show the fine frequency detection ability of the filter bank. This model can also be used to abstract the fundamental frequency of speech and to measure the frequency of pure tone precisely.

  13. Frequency band-importance functions for auditory and auditory-visual speech recognition

    Science.gov (United States)

    Grant, Ken W.

    2005-04-01

    In many everyday listening environments, speech communication involves the integration of both acoustic and visual speech cues. This is especially true in noisy and reverberant environments where the speech signal is highly degraded, or when the listener has a hearing impairment. Understanding the mechanisms involved in auditory-visual integration is a primary interest of this work. Of particular interest is whether listeners are able to allocate their attention to various frequency regions of the speech signal differently under auditory-visual conditions and auditory-alone conditions. For auditory speech recognition, the most important frequency regions tend to be around 1500-3000 Hz, corresponding roughly to important acoustic cues for place of articulation. The purpose of this study is to determine the most important frequency region under auditory-visual speech conditions. Frequency band-importance functions for auditory and auditory-visual conditions were obtained by having subjects identify speech tokens under conditions where the speech-to-noise ratio of different parts of the speech spectrum is independently and randomly varied on every trial. Point biserial correlations were computed for each separate spectral region and the normalized correlations are interpreted as weights indicating the importance of each region. Relations among frequency-importance functions for auditory and auditory-visual conditions will be discussed.

  14. A Time-Frequency Auditory Model Using Wavelet Packets

    DEFF Research Database (Denmark)

    Agerkvist, Finn

    1996-01-01

    A time-frequency auditory model is presented. The model uses the wavelet packet analysis as the preprocessor. The auditory filters are modelled by the rounded exponential filters, and the excitation is smoothed by a window function. By comparing time-frequency excitation patterns it is shown that...

  15. Frequency difference beyond behavioral limen reflected by frequency following response of human auditory Brainstem

    OpenAIRE

    Xu, Qin; Gong, Qin

    2014-01-01

    Background The present study investigated whether the frequency-following response (FFR) of the auditory brainstem can represent individual frequency-discrimination ability. Method We measured behavioral frequency-difference limens (FDLs) in normal hearing young adults. Then FFRs were evoked by two pure tones, whose frequency difference was no larger than behavioral FDL. Discrimination of FFRs to individual frequencies was conducted as the neural representation of stimulus frequency differenc...

  16. Auditory priming of frequency and temporal information: Effects of lateralized presentation

    OpenAIRE

    List, Alexandra; Justus, Timothy

    2007-01-01

    Asymmetric distribution of function between the cerebral hemispheres has been widely investigated in the auditory modality. The current approach borrows heavily from visual local-global research in an attempt to determine whether, as in vision, local-global auditory processing is lateralized. In vision, lateralized local-global processing likely relies on spatial frequency information. Drawing analogies between visual spatial frequency and auditory dimensions, two sets of auditory stimuli wer...

  17. The Effects of Auditory Selective Attention on Contralateral Suppression of Stimulus-Frequency Otoacoustic Emissions

    Directory of Open Access Journals (Sweden)

    Bahram Jalaee

    2011-09-01

    Full Text Available Background and Aim: To date, the function of auditory efferent system remains unclear. There is evidence that medial olivocochlear bundle receives descending input from the cortex. In this study, the effect of auditory selective attention on stimulus-frequency otoacoustic emissions (SFOAE was analyzed to investigate the modification of peripheral auditory system by auditory cortex activity in frequency specific mode.Methods: Thirty-six normal hearing adult subjects with their age ranging from 18 to 30 years (mean age: 21.9 years participated in this cross-sectional study. Contralateral suppression of stimulus-frequency otoacoustic emissions was recorded in the right ear at 2 KHz. In order to eliminate the auditory attention, subjects were instructed to read a text. Besides, in order to evaluate the effect of auditory attention on contralateral suppression, subjects were instructed to detect target tones in background noise at 1000, 2000, and 4000 KHz.Results: A significant increase at contralateral suppression of stimulus-frequency otoacoustic emissions was observed in auditory selective attention conditions (p≤0.001. The largest magnitude of stimulus-frequency otoacoustic emissions suppression was seen at 2 KHz.Conclusion: The results of this study indicated that the activities of medial olivocochlear bundle enhanced by contralateral auditory selective attention increase the magnitude of stimulus-frequency otoacoustic emissions suppression. In fact, these results provided evidence for influence of auditory cortex on the peripheral auditory system via corticofugal pathways in a frequency specific way.

  18. Auditory Processing in Children with Specific Language Impairments: Are there Deficits in Frequency Discrimination, Temporal Auditory Processing or General Auditory Processing?

    OpenAIRE

    Nickisch, Andreas; Massinger, Claudia

    2009-01-01

    Background/Aims: Specific language impairment (SLI) is believed to be associated with nonverbal auditory (NVA) deficits. It remains unclear, however, whether children with SLI show deficits in auditory time processing, time processing in general, frequency discrimination (FD), or NVA processing in general. Patients and Methods: Twenty-seven children (aged 8-11) with SLI and 27 control children (CG), matched for age and gender, were retrospectively compared with regard to their performance on ...

  19. Across frequency processes involved in auditory detection of coloration

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Kerketsos, P

    2008-01-01

    When an early wall reflection is added to a direct sound, a spectral modulation is introduced to the signal's power spectrum. This spectral modulation typically produces an auditory sensation of coloration or pitch. Throughout this study, auditory spectral-integration effects involved in coloration...... detection are investigated. Coloration detection thresholds were therefore measured as a function of reflection delay and stimulus bandwidth. In order to investigate the involved auditory mechanisms, an auditory model was employed that was conceptually similar to the peripheral weighting model [Yost, JASA...... filterbank was designed to approximate auditory filter-shapes measured by Oxenham and Shera [JARO, 2003, 541-554], derived from forward masking data. The results of the present study demonstrate that a “purely” spectrum-based model approach can successfully describe auditory coloration detection even at high...

  20. Frequency-specific disruptions of neuronal oscillations reveal aberrant auditory processing in schizophrenia.

    Science.gov (United States)

    Hayrynen, Lauren K; Hamm, Jordan P; Sponheim, Scott R; Clementz, Brett A

    2016-06-01

    Individuals with schizophrenia exhibit abnormalities in evoked brain responses in oddball paradigms. These could result from (a) insufficient salience-related cortical signaling (P300), (b) insufficient suppression of irrelevant aspects of the auditory environment, or (c) excessive neural noise. We tested whether disruption of ongoing auditory steady-state responses at predetermined frequencies informed which of these issues contribute to auditory stimulus relevance processing abnormalities in schizophrenia. Magnetoencephalography data were collected for 15 schizophrenia and 15 healthy subjects during an auditory oddball paradigm (25% targets; 1-s interstimulus interval). Auditory stimuli (pure tones: 1 kHz standards, 2 kHz targets) were administered during four continuous background (auditory steady-state) stimulation conditions: (1) no stimulation, (2) 24 Hz, (3) 40 Hz, and (4) 88 Hz. The modulation of the auditory steady-state response (aSSR) and the evoked responses to the transient stimuli were quantified and compared across groups. In comparison to healthy participants, the schizophrenia group showed greater disruption of the ongoing aSSR by targets regardless of steady-state frequency, and reduced amplitude of both M100 and M300 event-related field components. During the no-stimulation condition, schizophrenia patients showed accentuation of left hemisphere 40 Hz response to both standard and target stimuli, indicating an effort to enhance local stimulus processing. Together, these findings suggest abnormalities in auditory stimulus relevance processing in schizophrenia patients stem from insufficient amplification of salient stimuli. PMID:26933842

  1. Cortical contributions to the auditory frequency-following response revealed by MEG.

    Science.gov (United States)

    Coffey, Emily B J; Herholz, Sibylle C; Chepesiuk, Alexander M P; Baillet, Sylvain; Zatorre, Robert J

    2016-01-01

    The auditory frequency-following response (FFR) to complex periodic sounds is used to study the subcortical auditory system, and has been proposed as a biomarker for disorders that feature abnormal sound processing. Despite its value in fundamental and clinical research, the neural origins of the FFR are unclear. Using magnetoencephalography, we observe a strong, right-asymmetric contribution to the FFR from the human auditory cortex at the fundamental frequency of the stimulus, in addition to signal from cochlear nucleus, inferior colliculus and medial geniculate. This finding is highly relevant for our understanding of plasticity and pathology in the auditory system, as well as higher-level cognition such as speech and music processing. It suggests that previous interpretations of the FFR may need re-examination using methods that allow for source separation. PMID:27009409

  2. Psychophysical Estimates of Frequency Discrimination: More than Just Limitations of Auditory Processing

    OpenAIRE

    Beate Sabisch; Benjamin Weiss; Barry, Johanna G.

    2013-01-01

    Efficient auditory processing is hypothesized to support language and literacy development. However, behavioral tasks used to assess this hypothesis need to be robust to non-auditory specific individual differences. This study compared frequency discrimination abilities in a heterogeneous sample of adults using two different psychoacoustic task designs, referred to here as: 2I_6A_X and 3I_2AFC designs. The role of individual differences in nonverbal IQ (NVIQ), socioeconomic status (SES) and m...

  3. Seasonal plasticity of auditory hair cell frequency sensitivity correlates with plasma steroid levels in vocal fish

    OpenAIRE

    Rohmann, Kevin N.; Bass, Andrew H.

    2011-01-01

    Vertebrates displaying seasonal shifts in reproductive behavior provide the opportunity to investigate bidirectional plasticity in sensory function. The midshipman teleost fish exhibits steroid-dependent plasticity in frequency encoding by eighth nerve auditory afferents. In this study, evoked potentials were recorded in vivo from the saccule, the main auditory division of the inner ear of most teleosts, to test the hypothesis that males and females exhibit seasonal changes in hair cell physi...

  4. Frequency Selectivity Behaviour in the Auditory Midbrain: Implications of Model Study

    Institute of Scientific and Technical Information of China (English)

    KUANG Shen-Bing; WANG Jia-Fu; ZENG Ting

    2006-01-01

    By numerical simulations on frequency dependence of the spiking threshold, i.e. on the critical amplitude of periodic stimulus, for a neuron to fire, we find that bushy cells in the cochlear nuclear exhibit frequency selectivity behaviour. However, the selective frequency band of a bushy cell is far away from that of the preferred spectral range in human and mammal auditory perception. The mechanism underlying this neural activity is also discussed. Further studies show that the ion channel densities have little impact on the selective frequency band of bushy cells. These findings suggest that the neuronal behaviour of frequency selectivity in bushy cells at both the single cell and population levels may be not functionally relevant to frequency discrimination. Our results may reveal a neural hint to the reconsideration on the bushy cell functional role in auditory information processing of sound frequency.

  5. Sensorimotor learning in children and adults: Exposure to frequency-altered auditory feedback during speech production.

    Science.gov (United States)

    Scheerer, N E; Jacobson, D S; Jones, J A

    2016-02-01

    Auditory feedback plays an important role in the acquisition of fluent speech; however, this role may change once speech is acquired and individuals no longer experience persistent developmental changes to the brain and vocal tract. For this reason, we investigated whether the role of auditory feedback in sensorimotor learning differs across children and adult speakers. Participants produced vocalizations while they heard their vocal pitch predictably or unpredictably shifted downward one semitone. The participants' vocal pitches were measured at the beginning of each vocalization, before auditory feedback was available, to assess the extent to which the deviant auditory feedback modified subsequent speech motor commands. Sensorimotor learning was observed in both children and adults, with participants' initial vocal pitch increasing following trials where they were exposed to predictable, but not unpredictable, frequency-altered feedback. Participants' vocal pitch was also measured across each vocalization, to index the extent to which the deviant auditory feedback was used to modify ongoing vocalizations. While both children and adults were found to increase their vocal pitch following predictable and unpredictable changes to their auditory feedback, adults produced larger compensatory responses. The results of the current study demonstrate that both children and adults rapidly integrate information derived from their auditory feedback to modify subsequent speech motor commands. However, these results also demonstrate that children and adults differ in their ability to use auditory feedback to generate compensatory vocal responses during ongoing vocalization. Since vocal variability also differed across the children and adult groups, these results also suggest that compensatory vocal responses to frequency-altered feedback manipulations initiated at vocalization onset may be modulated by vocal variability. PMID:26628403

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

    Directory of Open Access Journals (Sweden)

    Alexandre Lehmann

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

  7. Effects of auditory training in individuals with high-frequency hearing loss

    Directory of Open Access Journals (Sweden)

    Renata Beatriz Fernandes Santos

    2014-01-01

    Full Text Available OBJECTIVE: To determine the effects of a formal auditory training program on the behavioral, electrophysiological and subjective aspects of auditory function in individuals with bilateral high-frequency hearing loss. METHOD: A prospective study of seven individuals aged 46 to 57 years with symmetric, moderate high-frequency hearing loss ranging from 3 to 8 kHz was conducted. Evaluations of auditory processing (sound location, verbal and non-verbal sequential memory tests, the speech-in-noise test, the staggered spondaic word test, synthetic sentence identification with competitive ipsilateral and contralateral competitive messages, random gap detection and the standard duration test, auditory brainstem response and long-latency potentials and the administration of the Abbreviated Profile of Hearing Aid Benefit questionnaire were performed in a sound booth before and immediately after formal auditory training. RESULTS: All of the participants demonstrated abnormal pre-training long-latency characteristics (abnormal latency or absence of the P3 component and these abnormal characteristics were maintained in six of the seven individuals at the post-training evaluation. No significant differences were found between ears in the quantitative analysis of auditory brainstem responses or long-latency potentials. However, the subjects demonstrated improvements on all behavioral tests. For the questionnaire, the difference on the background noise subscale achieved statistical significance. CONCLUSION: Auditory training in adults with high-frequency hearing loss led to improvements in figure-background hearing skills for verbal sounds, temporal ordination and resolution, and communication in noisy environments. Electrophysiological changes were also observed because, after the training, some long latency components that were absent pre-training were observed during the re-evaluation.

  8. The auditory nerve overlapped waveform (ANOW): A new objective measure of low-frequency hearing

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    Lichtenhan, Jeffery T.; Salt, Alec N.; Guinan, John J.

    2015-12-01

    One of the most pressing problems today in the mechanics of hearing is to understand the mechanical motions in the apical half of the cochlea. Almost all available measurements from the cochlear apex of basilar membrane or other organ-of-Corti transverse motion have been made from ears where the health, or sensitivity, in the apical half of the cochlea was not known. A key step in understanding the mechanics of the cochlear base was to trust mechanical measurements only when objective measures from auditory-nerve compound action potentials (CAPs) showed good preparation sensitivity. However, such traditional objective measures are not adequate monitors of cochlear health in the very low-frequency regions of the apex that are accessible for mechanical measurements. To address this problem, we developed the Auditory Nerve Overlapped Waveform (ANOW) that originates from auditory nerve output in the apex. When responses from the round window to alternating low-frequency tones are averaged, the cochlear microphonic is canceled and phase-locked neural firing interleaves in time (i.e., overlaps). The result is a waveform that oscillates at twice the probe frequency. We have demonstrated that this Auditory Nerve Overlapped Waveform - called ANOW - originates from auditory nerve fibers in the cochlear apex [8], relates well to single-auditory-nerve-fiber thresholds, and can provide an objective estimate of low-frequency sensitivity [7]. Our new experiments demonstrate that ANOW is a highly sensitive indicator of apical cochlear function. During four different manipulations to the scala media along the cochlear spiral, ANOW amplitude changed when either no, or only small, changes occurred in CAP thresholds. Overall, our results demonstrate that ANOW can be used to monitor cochlear sensitivity of low-frequency regions during experiments that make apical basilar membrane motion measurements.

  9. Frequency sensitivity in the auditory periphery of male and female black-capped chickadees (Poecile atricapillus).

    Science.gov (United States)

    Wong, Arick; Gall, Megan D

    2015-10-01

    The black-capped chickadee is a songbird that has been used extensively as a model of animal communication in field and laboratory settings. Although many studies have focused on the complex call and song systems of the black-capped chickadee, relatively fewer studies have focused on chickadee audition. However, we do know from behavioral and molecular work that chickadees (and auditory processing areas in their brains) discriminate between artificially generated tones, between conspecific and heterospecific vocalizations, and among different types of conspecific vocalizations. In this paper we investigate peripheral auditory processing of frequency in the black-capped chickadee and the potential influence of sex on frequency sensitivity using a technique called auditory evoked potentials. We found that male and female black-capped chickadees did not differ in any measure of frequency sensitivity. Both sexes had the greatest sensitivity to frequencies between 2 and 4 kHz. This range of frequencies is well represented in black-capped chickadee song, partially supporting the idea that sender and receiver coevolve. Finally, we suggest that the call and song system of North American parids make them an ideal taxonomic group for comparative work exploring the relationship between call systems and the evolution of auditory processing. PMID:26163861

  10. Auditory Frequency Discrimination in Adults with Dyslexia: A Test of the Anchoring Hypothesis

    Science.gov (United States)

    Wijnen, Frank; Kappers, Astrid M. L.; Vlutters, Leoni D.; Winkel, Sven

    2012-01-01

    Purpose: A recent hypothesis ascribes dyslexia to a perceptual anchoring deficit. Supporting results have so far been obtained only in children with dyslexia and additional learning difficulties, but the hypothesis has been argued to apply to all individuals with dyslexia. Method: The authors measured auditory frequency discrimination thresholds…

  11. Auditory Frequency Discrimination in Children with Specific Language Impairment: A Longitudinal Study

    Science.gov (United States)

    Hill, P. R.; Hogben, J. H.; Bishop, D. M. V.

    2005-01-01

    It has been proposed that specific language impairment (SLI) is caused by an impairment of auditory processing, but it is unclear whether this problem affects temporal processing, frequency discrimination (FD), or both. Furthermore, there are few longitudinal studies in this area, making it hard to establish whether any deficit represents a…

  12. Neural Resolution of Formant Frequencies in the Primary Auditory Cortex of Rats

    OpenAIRE

    Honey, Christian; Schnupp, Jan

    2015-01-01

    Pulse-resonance sounds play an important role in animal communication and auditory object recognition, yet very little is known about the cortical representation of this class of sounds. In this study we shine light on one simple aspect: how well does the firing rate of cortical neurons resolve resonant (“formant”) frequencies of vowel-like pulse-resonance sounds. We recorded neural responses in the primary auditory cortex (A1) of anesthetized rats to two-formant pulse-resonance sounds, and e...

  13. SPET monitoring of perfusion changes in auditory cortex following mono- and multi-frequency stimuli

    International Nuclear Information System (INIS)

    In order to assess the relationship between auditory cortex perfusion and the frequency of acoustic stimuli, twenty normally-hearing subjects underwent cerebral SPET. In 10 patients a multi-frequency stimulus (250-4000 Hz at 40 dB SL) was delivered, while 10 subjects were stimulated with a 500 Hz pure tone at 40 dB SL. The prestimulation SPET was subtracted from poststimulation study and auditory cortex activation was expressed as percent increments. Contralateral cortex was the most active area with multifrequency and monofrequency stimuli as well. A clear demonstration of a tonotopic distribution of acoustic stimuli in the auditory cortex was achieved. In addition, the accessory role played by homolateral accoustic areas was confirmed. The results of the present research support the hypothesis that brain SPET may be useful to obtain semiquantitative reliable information on low frequency auditory level in profoundly deaf patients. This may be achieved comparing the extension of the cortical areas activated by high-intensity multifrequency stimuli. (orig.)

  14. Neural Resolution of Formant Frequencies in the Primary Auditory Cortex of Rats.

    Science.gov (United States)

    Honey, Christian; Schnupp, Jan

    2015-01-01

    Pulse-resonance sounds play an important role in animal communication and auditory object recognition, yet very little is known about the cortical representation of this class of sounds. In this study we shine light on one simple aspect: how well does the firing rate of cortical neurons resolve resonant ("formant") frequencies of vowel-like pulse-resonance sounds. We recorded neural responses in the primary auditory cortex (A1) of anesthetized rats to two-formant pulse-resonance sounds, and estimated their formant resolving power using a statistical kernel smoothing method which takes into account the natural variability of cortical responses. While formant-tuning functions were diverse in structure across different penetrations, most were sensitive to changes in formant frequency, with a frequency resolution comparable to that reported for rat cochlear filters. PMID:26252382

  15. Auditory Discrimination of Frequency Ratios: The Octave Singularity

    Science.gov (United States)

    Bonnard, Damien; Micheyl, Christophe; Semal, Catherine; Dauman, Rene; Demany, Laurent

    2013-01-01

    Sensitivity to frequency ratios is essential for the perceptual processing of complex sounds and the appreciation of music. This study assessed the effect of ratio simplicity on ratio discrimination for pure tones presented either simultaneously or sequentially. Each stimulus consisted of four 100-ms pure tones, equally spaced in terms of…

  16. Auditory attention to frequency and time: an analogy to visual local–global stimuli

    OpenAIRE

    Justus, Timothy; List, Alexandra

    2005-01-01

    Two priming experiments demonstrated exogenous attentional persistence to the fundamental auditory dimensions of frequency (Experiment 1) and time (Experiment 2). In a divided-attention task, participants responded to an independent dimension, the identification of three-tone sequence patterns, for both prime and probe stimuli. The stimuli were specifically designed to parallel the local–global hierarchical letter stimuli of [Navon D. (1977). Forest before trees: The precedence of global feat...

  17. Volume Attenuation and High Frequency Loss as Auditory Depth Cues in Stereoscopic 3D Cinema

    Science.gov (United States)

    Manolas, Christos; Pauletto, Sandra

    2014-09-01

    Assisted by the technological advances of the past decades, stereoscopic 3D (S3D) cinema is currently in the process of being established as a mainstream form of entertainment. The main focus of this collaborative effort is placed on the creation of immersive S3D visuals. However, with few exceptions, little attention has been given so far to the potential effect of the soundtrack on such environments. The potential of sound both as a means to enhance the impact of the S3D visual information and to expand the S3D cinematic world beyond the boundaries of the visuals is large. This article reports on our research into the possibilities of using auditory depth cues within the soundtrack as a means of affecting the perception of depth within cinematic S3D scenes. We study two main distance-related auditory cues: high-end frequency loss and overall volume attenuation. A series of experiments explored the effectiveness of these auditory cues. Results, although not conclusive, indicate that the studied auditory cues can influence the audience judgement of depth in cinematic 3D scenes, sometimes in unexpected ways. We conclude that 3D filmmaking can benefit from further studies on the effectiveness of specific sound design techniques to enhance S3D cinema.

  18. Observations on auditory learning in amplitude- and frequency-modulation rate discrimination

    DEFF Research Database (Denmark)

    Hoffmann, Pablo F.

    2010-01-01

    Because amplitude- and frequency-modulated sounds can be the basis for the synthesis of many complex sounds, they can be good candidates in the design of training systems aiming at improving the acquisition of perceptual skills that can benefit from information provided via the auditory channel......-training, training, a post-training stages. During training, listeners were divided into two groups; one group trained on amplitude-modulation rate discrimination and the other group trained on frequency-modulation rate discrimination. Results will be discussed in terms of their implications for training...

  19. Psychophysical Estimates of Frequency Discrimination: More than Just Limitations of Auditory Processing

    Directory of Open Access Journals (Sweden)

    Beate Sabisch

    2013-07-01

    Full Text Available Efficient auditory processing is hypothesized to support language and literacy development. However, behavioral tasks used to assess this hypothesis need to be robust to non-auditory specific individual differences. This study compared frequency discrimination abilities in a heterogeneous sample of adults using two different psychoacoustic task designs, referred to here as: 2I_6A_X and 3I_2AFC designs. The role of individual differences in nonverbal IQ (NVIQ, socioeconomic status (SES and musical experience in predicting frequency discrimination thresholds on each task were assessed using multiple regression analyses. The 2I_6A_X task was more cognitively demanding and hence more susceptible to differences specifically in SES and musical training. Performance on this task did not, however, relate to nonword repetition ability (a measure of language learning capacity. The 3I_2AFC task, by contrast, was only susceptible to musical training. Moreover, thresholds measured using it predicted some variance in nonword repetition performance. This design thus seems suitable for use in studies addressing questions regarding the role of auditory processing in supporting language and literacy development.

  20. Multi-frequency auditory stimulation disrupts spindling activity in anesthetized animals.

    Science.gov (United States)

    Britvina, T; Eggermont, J J

    2008-02-01

    It is often implied that during the occurrence of spindle oscillations, thalamocortical neurons do not respond to signals from the outside world. Since recording of sound-evoked activity from cat auditory cortex is common during spindling this implies that sound stimulation changes the spindle-related brain state. Local field potentials and multi-unit activity recorded from cat primary auditory cortex under ketamine anesthesia during successive silence-stimulus-silence conditions were used to investigate the effect of sound on cortical spindle oscillations. Multi-frequency stimulation suppresses spindle waves, as shown by the decrease of spectral power within the spindle frequency range during stimulation as compared with the previous silent period. We show that the percentage suppression is independent of the power of the spindle waves during silence, and that the suppression of spindle power occurs very fast after stimulus onset. The global inter-spindle rhythm was not disturbed during stimulation. Spectrotemporal and correlation analysis revealed that beta waves (15-26 Hz), and to a lesser extent delta waves, were modulated by the same inter-spindle rhythm as spindle oscillations. The suppression of spindle power during stimulation had no effect on the spatial correlation of spindle waves. Firing rates increased under stimulation and spectro-temporal receptive fields could reliably be obtained. The possible mechanism of suppression of spindle waves is discussed and it is suggested that suppression likely occurs through activity of the specific auditory pathway. PMID:18164553

  1. Frequency processing at consecutive levels in the auditory system of bush crickets (tettigoniidae).

    Science.gov (United States)

    Ostrowski, Tim Daniel; Stumpner, Andreas

    2010-08-01

    We asked how processing of male signals in the auditory pathway of the bush cricket Ancistrura nigrovittata (Phaneropterinae, Tettigoniidae) changes from the ear to the brain. From 37 sensory neurons in the crista acustica single elements (cells 8 or 9) have frequency tuning corresponding closely to the behavioral tuning of the females. Nevertheless, one-quarter of sensory neurons (approximately cells 9 to 18) excite the ascending neuron 1 (AN1), which is best tuned to the male's song carrier frequency. AN1 receives frequency-dependent inhibition, reducing sensitivity especially in the ultrasound. When recorded in the brain, AN1 shows slightly lower overall activity than when recorded in the prothoracic ganglion close to the spike-generating zone. This difference is significant in the ultrasonic range. The first identified local brain neuron in a bush cricket (LBN1) is described. Its dendrites overlap with some of AN1-terminations in the brain. Its frequency tuning and intensity dependence strongly suggest a direct postsynaptic connection to AN1. Spiking in LBN1 is only elicited after summation of excitatory postsynaptic potentials evoked by individual AN1-action potentials. This serves a filtering mechanism that reduces the sensitivity of LBN1 and also its responsiveness to ultrasound as compared to AN1. Consequently, spike latencies of LBN1 are long (>30 ms) despite its being a second-order interneuron. Additionally, LBN1 receives frequency-specific inhibition, most likely further reducing its responses to ultrasound. This demonstrates that frequency-specific inhibition is redundant in two directly connected interneurons on subsequent levels in the auditory system. PMID:20533362

  2. 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

  3. Instantaneous and Frequency-Warped Signal Processing Techniques for Auditory Source Separation.

    Science.gov (United States)

    Wang, Avery Li-Chun

    This thesis summarizes several contributions to the areas of signal processing and auditory source separation. The philosophy of Frequency-Warped Signal Processing is introduced as a means for separating the AM and FM contributions to the bandwidth of a complex-valued, frequency-varying sinusoid p (n), transforming it into a signal with slowly-varying parameters. This transformation facilitates the removal of p (n) from an additive mixture while minimizing the amount of damage done to other signal components. The average winding rate of a complex-valued phasor is explored as an estimate of the instantaneous frequency. Theorems are provided showing the robustness of this measure. To implement frequency tracking, a Frequency-Locked Loop algorithm is introduced which uses the complex winding error to update its frequency estimate. The input signal is dynamically demodulated and filtered to extract the envelope. This envelope may then be remodulated to reconstruct the target partial, which may be subtracted from the original signal mixture to yield a new, quickly-adapting form of notch filtering. Enhancements to the basic tracker are made which, under certain conditions, attain the Cramer -Rao bound for the instantaneous frequency estimate. To improve tracking, the novel idea of Harmonic -Locked Loop tracking, using N harmonically constrained trackers, is introduced for tracking signals, such as voices and certain musical instruments. The estimated fundamental frequency is computed from a maximum-likelihood weighting of the N tracking estimates, making it highly robust. The result is that harmonic signals, such as voices, can be isolated from complex mixtures in the presence of other spectrally overlapping signals. Additionally, since phase information is preserved, the resynthesized harmonic signals may be removed from the original mixtures with relatively little damage to the residual signal. Finally, a new methodology is given for designing linear-phase FIR filters

  4. Auditory Discrimination Using Frequency-Modulated Amplification with Long-Term Amplitude Compression.

    Science.gov (United States)

    Shea, Bernard David

    This dissertation considers the effects of long -term amplitude compression used in narrow-band frequency modulated (FM) assistive listening devices on the auditory discrimination of severely and profoundly hearing-impaired individuals. Compression has been used in narrow-band FM transmitters for hearing-impaired children in educational programs for over twenty years. It restricts the peak deviation of the FM signal to within allowable limits. Narrow -band FM equipment can vary in peak limitation approaches via compression, i.e., using a form of compression limiting or using long-term compression (automatic volume control). Numerous investigations have studied the benefits of FM system use, but none have tested the benefits or deleterious effects of these compression forms on the auditory discrimination of hearing-impaired individuals. Despite the marked limitations associated with severe or profound sensorineural hearing impairment in children, spoken language development is possible. Research and experience have suggested that the auditory system represents the best sensory input channel for these children. With appropriate amplification and educational intervention they can achieve dramatic improvements in speech perception, speech production, language development, and educational achievement (Boothroyd, 1985; Hudgins, 1953, 1954; Ling & Milne, 1981; Wedenberg, 1954). Most hearing-impaired children in educational programs across the United States receive the amplified teacher's speech signal via narrow-band frequency modulated (FM) transmission, yet a controlled investigation of the input compression used in these systems has never been conducted. This dissertation reviews and discusses narrow -band frequency modulated (FM) radio wave systems and the use of audio compression. The experiment tested 32 students with severe to profound sensorineural hearing loss under two narrow -band FM transmitter conditions. The FM transmitter conditions were varied on the basis

  5. Cortical Auditory Event Related Potentials (P300) for Frequency Changing Dynamic Tones

    Science.gov (United States)

    Kalaiah, Mohan Kumar

    2016-01-01

    Background and Objectives P300 has been studied with a variety of stimuli. However, the nature of P300 has not been investigated for deviant stimuli which change its characteristics from standard stimuli after a period of time from onset. Subjects and Methods Nine young adults with normal hearing participated in the study. The P300 was elicited using an oddball paradigm, the probability of standard and deviant stimuli was 80% and 20% respectively. Six stimuli were used to elicit P300, it included two pure-tones (1,000 Hz and 2,000 Hz) and four tone-complexes (tones with frequency changes). Among these stimuli, 1,000 Hz tone served as standard while others served as deviant stimuli. The P300 was recorded in five separate blocks, with one of the deviant stimuli as target in each block. Electroencephalographic was recorded from electrode sites Fz, Cz, C3, C4, and Pz. Latency and amplitude of components of the cortical auditory evoked potentials were measured at Cz. Results Waveforms obtained in the present study shows that, all the deviant stimuli elicited obligatory P1-N1-P2 for stimulus onset. 2,000 Hz deviant tone elicited P300 at a latency of 300 ms. While, tone-complexes elicited acoustic change complex (ACC) for frequency changes and finally elicited P300 at a latency of 600 ms. In addition, the results showed shorter latency and larger amplitude ACC and P300 for rising tone-complexes compared to falling tone-complexes. Conclusions Tone-complexes elicited distinct waveforms compared to 2,000 Hz deviant tone. Rising tone-complexes which had an increase in frequency elicited shorter latency and larger amplitude responses, which could be attributed to perceptual bias for frequency changes. PMID:27144230

  6. Auditory Neuropathy

    Science.gov (United States)

    ... field differ in their opinions about the potential benefits of hearing aids, cochlear implants, and other technologies for people with auditory neuropathy. Some professionals report that hearing aids and personal listening devices such as frequency modulation (FM) systems are ...

  7. Endogenous auditory frequency-based attention modulates electroencephalogram-based measures of obligatory sensory activity in humans.

    Science.gov (United States)

    Sheedy, Caroline M; Power, Alan J; Reilly, Richard B; Crosse, Michael J; Loughnane, Gerard M; Lalor, Edmund C

    2014-03-01

    Auditory selective attention is the ability to enhance the processing of a single sound source, while simultaneously suppressing the processing of other competing sound sources. Recent research has addressed a long-running debate by showing that endogenous attention produces effects on obligatory sensory responses to continuous and competing auditory stimuli. However, until now, this result has only been shown under conditions where the competing stimuli differed in both their frequency characteristics and, importantly, their spatial location. Thus, it is unknown whether endogenous selective attention based only on nonspatial features modulates obligatory sensory processing. Here, we investigate this issue using a diotic paradigm, such that competing auditory stimuli differ in frequency, but had no separation in space. We find a significant effect of attention on electroencephalogram-based measures of obligatory sensory processing at several poststimulus latencies. We discuss these results in terms of previous research on feature-based attention and by comparing our findings with the previous work using stimuli that differed both in terms of spatial and frequency-based characteristics. PMID:24231831

  8. Systematic Review of the Effectiveness of Frequency Modulation Devices in Improving Academic Outcomes in Children With Auditory Processing Difficulties.

    Science.gov (United States)

    Reynolds, Stacey; Miller Kuhaneck, Heather; Pfeiffer, Beth

    2016-01-01

    This systematic review describes the published evidence related to the effectiveness of frequency modulation (FM) devices in improving academic outcomes in children with auditory processing difficulties. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards were used to identify articles published between January 2003 and March 2014. The Cochrane Population, Intervention, Control, Outcome, Study Design approach and the American Occupational Therapy Association process forms were used to guide the article selection and evaluation process. Of the 83 articles screened, 7 matched the systematic review inclusion criteria. Findings were consistently positive, although limitations were identified. Results of this review indicate moderate support for the use of FM devices to improve children's ability to listen and attend in the classroom and mixed evidence to improve specific academic performance areas. FM technology should be considered for school-age children with auditory processing impairments who are receiving occupational therapy services to improve functioning in the school setting. PMID:26709423

  9. The perception of coherent and non-coherent auditory objects: a signature in gamma frequency band.

    Science.gov (United States)

    Knief, A; Schulte, M; Bertran, O; Pantev, C

    2000-07-01

    The pertinence of gamma band activity in magnetoencephalographic and electroencephalographic recordings for the performance of a gestalt recognition process is a question at issue. We investigated the functional relevance of gamma band activity for the perception of auditory objects. An auditory experiment was performed as an analog to the Kanizsa experiment in the visual modality, comprising four different coherent and non-coherent stimuli. For the first time functional differences of evoked gamma band activity due to the perception of these stimuli were demonstrated by various methods (localization of sources, wavelet analysis and independent component analysis, ICA). Responses to coherent stimuli were found to have more features in common compared to non-coherent stimuli (e.g. closer located sources and smaller number of ICA components). The results point to the existence of a pitch processor in the auditory pathway. PMID:10867289

  10. Zebrafish forebrain and temporal conditioning

    OpenAIRE

    Cheng, Ruey-Kuang; Jesuthasan, Suresh J.; Penney, Trevor B.

    2014-01-01

    The rise of zebrafish as a neuroscience research model organism, in conjunction with recent progress in single-cell resolution whole-brain imaging of larval zebrafish, opens a new window of opportunity for research on interval timing. In this article, we review zebrafish neuroanatomy and neuromodulatory systems, with particular focus on identifying homologies between the zebrafish forebrain and the mammalian forebrain. The neuroanatomical and neurochemical basis of interval timing is summariz...

  11. High frequency bone conduction auditory evoked potentials in the guinea pig: Assessing cochlear injury after ossicular chain manipulation.

    Science.gov (United States)

    Bergin, M J; Bird, P A; Vlajkovic, S M; Thorne, P R

    2015-12-01

    Permanent high frequency (>4 kHz) sensorineural hearing loss following middle ear surgery occurs in up to 25% of patients. The aetiology of this loss is poorly understood and may involve transmission of supra-physiological forces down the ossicular chain to the cochlea. Investigating the mechanisms of this injury using animal models is challenging, as evaluating cochlear function with evoked potentials is confounded when ossicular manipulation disrupts the normal air conduction (AC) pathway. Bone conduction (BC) using clinical bone vibrators in small animals is limited by poor transducer output at high frequencies sensitive to trauma. The objectives of the present study were firstly to evaluate a novel high frequency bone conduction transducer with evoked auditory potentials in a guinea pig model, and secondly to use this model to investigate the impact of middle ear surgical manipulation on cochlear function. We modified a magnetostrictive device as a high frequency BC transducer and evaluated its performance by comparison with a calibrated AC transducer at frequencies up to 32 kHz using the auditory brainstem response (ABR), compound action potential (CAP) and summating potential (SP). To mimic a middle ear traumatising stimulus, a rotating bur was brought in to contact with the incudomalleal complex and the effect on evoked cochlear potentials was observed. BC-evoked potentials followed the same input-output function pattern as AC potentials for all ABR frequencies. Deterioration in CAP and SP thresholds was observed after ossicular manipulation. It is possible to use high frequency BC to evoke responses from the injury sensitive basal region of the cochlea and so not rely on AC with the potential confounder of conductive hearing loss. Ongoing research explores how these findings evolve over time, and ways in which injury may be reduced and the cochlea protected during middle ear surgery. PMID:26493491

  12. ONTOGENY OF EYEBLINK CONDITIONING IN THE RAT: AUDITORY FREQUENCY AND DISCRIMINATION LEARNING EFFECTS

    Science.gov (United States)

    The present study sought to determine whether acoustic properties of the auditory conditioned stimulus (CS) or the use of a discrimination learning procedure would alter the emergence of eyeblink conditioning between Postnatal Day 17 and 24 (PND17-24) in the rat. n Experiment 1, ...

  13. High-frequency ex vivo ultrasound imaging of the auditory system.

    NARCIS (Netherlands)

    Brown, J.A.; Torbatian, Z.; Adamson, R.B.; Wijhe, R. Van; Pennings, R.J.E.; Lockwood, G.R.; Bance, M.L.

    2009-01-01

    A 50MHz array-based imaging system was used to obtain high-resolution images of the ear and auditory system. This previously described custom built imaging system (Brown et al. 2004a, 2004b; Brown and Lockwood 2005) is capable of 50 microm axial resolution, and lateral resolution varying from 80 mic

  14. 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

  15. Epidural auditory event-related potentials in the rat to frequency and duration deviants: evidence of mismatch negativity?

    Directory of Open Access Journals (Sweden)

    Tamo eNakamura

    2011-12-01

    Full Text Available The capacity of the human brain to detect deviance in the acoustic environment pre-attentively is reflected in a brain event-related potential (ERP, mismatch negativity (MMN. MMN is observed in response to the presentation of rare oddball sounds that deviate from an otherwise regular pattern of frequent background standard sounds. While the primate and cat auditory cortex (AC exhibit MMN-like activity, it is unclear whether the rodent AC produces a deviant response that reflects deviance detection in a background of regularities evident in recent auditory stimulus history or differential adaptation of neuronal responses due to rarity of the deviant sound. We examined whether MMN-like activity occurs in epidural AC potentials in awake and anaesthetised rats to high and low frequency and long and short duration deviant sounds. ERPs to deviants were compared with ERPs to common standards and also with ERPs to deviants when interspersed with many different standards to control for background regularity effects. High frequency and long duration deviant ERPs in the awake rat showed evidence of deviance detection, consisting of negative displacements of the deviant ERP relative to ERPs to both common standards and deviants with many standards. The high frequency deviant MMN-like response was also sensitive to the extent of regularity in recent acoustic stimulation. Anaesthesia in contrast resulted in positive displacements of deviant ERPs. Our results suggest that epidural MMN-like potentials to high frequency sounds in awake rats encode deviance in an analogous manner to the human MMN, laying the foundation for animal models of disorders characterised by disrupted MMN generation, such as schizophrenia.

  16. Exposure setup to study potential adverse effects at GSM 1800 and UMTS frequencies on the auditory systems of rats

    International Nuclear Information System (INIS)

    To investigate possible biological effects of exposure to electromagnetic (EM) fields at the frequencies of global system for mobile communication (GSM) 1800 system and universal mobile telecommunication system (UMTS) on the auditory system of rats, an exposure setup for in vivo experiments is presented. The study was carried out in the framework of two European research projects. The target of the investigation was the cochlea. A dosimetric study was performed, both numerically and through direct measurements, to assess the interaction of the radiated fields and the dose distribution in the biological target. For the local exposure of rats, a loop antenna operating at the frequency bands of interest was designed, realised and characterised through numerical and experimental dosimetric procedures. Moreover, an exposure apparatus was set up, consisting of three arrays of four loop antennas, placed on three levels, thus allowing simultaneous exposure of 12 rats to give statistical power to the experiments. To isolate the exposure arrays, the setup was assembled by a wooden rack with EM field absorbing panels, inserted among the levels and at the four sides of the rack. Isolation was verified by direct measurements. Two exposure arrays were simultaneously supplied, whereas the third one was used for sham exposure. Blind exposure was achieved through a black box, hiding physical connections to the microwave power supply. During exposure sessions, rats were restrained in special plastic jigs for repeatable positioning, thus assuring the fixed level of dose in the target. (authors)

  17. Time-frequency analysis with temporal and spectral resolution as the human auditory system

    DEFF Research Database (Denmark)

    Agerkvist, Finn T.

    The human perception of sound is a suitable area for the application of a simultaneous time-frequency analysis, since the ear is selective in both domains. A perfect reconstruction filter bank with bandwidths approximating the critical bands is presented. The orthogonality of the filter makes it...

  18. Concurrent Encoding of Frequency and Amplitude Modulation in Human Auditory Cortex: Encoding Transition

    OpenAIRE

    Luo, H.; Wang, Y.; Poeppel, D.; Simon, J.Z.

    2007-01-01

    Complex natural sounds (e.g., animal vocalizations or speech) can be characterized by specific spectrotemporal patterns the components of which change in both frequency (FM) and amplitude (AM). The neural coding of AM and FM has been widely studied in humans and animals but typically with either pure AM or pure FM stimuli. The neural mechanisms employed to perceptually unify AM and FM acoustic features remain unclear. Using stimuli with simultaneous sinusoidal AM (at rate fAM = 37 Hz) and FM ...

  19. Cortical Auditory Evoked Potentials Reveal Changes in Audibility with Nonlinear Frequency Compression in Hearing Aids for Children: Clinical Implications.

    Science.gov (United States)

    Ching, Teresa Y C; Zhang, Vicky W; Hou, Sanna; Van Buynder, Patricia

    2016-02-01

    Hearing loss in children is detected soon after birth via newborn hearing screening. Procedures for early hearing assessment and hearing aid fitting are well established, but methods for evaluating the effectiveness of amplification for young children are limited. One promising approach to validating hearing aid fittings is to measure cortical auditory evoked potentials (CAEPs). This article provides first a brief overview of reports on the use of CAEPs for evaluation of hearing aids. Second, a study that measured CAEPs to evaluate nonlinear frequency compression (NLFC) in hearing aids for 27 children (between 6.1 and 16.8 years old) who have mild to severe hearing loss is reported. There was no significant difference in aided sensation level or the detection of CAEPs for /g/ between NLFC on and off conditions. The activation of NLFC was associated with a significant increase in aided sensation levels for /t/ and /s/. It also was associated with an increase in detection of CAEPs for /t/ and /s/. The findings support the use of CAEPs for checking audibility provided by hearing aids. Based on the current data, a clinical protocol for using CAEPs to validate audibility with amplification is presented. PMID:27587920

  20. Auditory Processing Disorders

    Science.gov (United States)

    Auditory Processing Disorders Auditory processing disorders (APDs) are referred to by many names: central auditory processing disorders , auditory perceptual disorders , and central auditory disorders . APDs ...

  1. Auditory Display

    DEFF Research Database (Denmark)

    volume. The conference's topics include auditory exploration of data via sonification and audification; real time monitoring of multivariate date; sound in immersive interfaces and teleoperation; perceptual issues in auditory display; sound in generalized computer interfaces; technologies supporting...

  2. Electrical stimulation of the auditory nerve: the coding of frequency, the perception of pitch and the development of cochlear implant speech processing strategies for profoundly deaf people.

    Science.gov (United States)

    Clark, G M

    1996-09-01

    1. The development of speech processing strategies for multiple-channel cochlear implants has depended on encoding sound frequencies and intensities as temporal and spatial patterns of electrical stimulation of the auditory nerve fibres so that speech information of most importance of intelligibility could be transmitted. 2. Initial physiological studies showed that rate encoding of electrical stimulation above 200 pulses/s could not reproduce the normal response patterns in auditory neurons for acoustic stimulation in the speech frequency range above 200 Hz and suggested that place coding was appropriate for the higher frequencies. 3. Rate difference limens in the experimental animal were only similar to those for sound up to 200 Hz. 4. Rate difference limens in implant patients were similar to those obtained in the experimental animal. 5. Satisfactory rate discrimination could be made for durations of 50 and 100 ms, but not 25 ms. This made rate suitable for encoding longer duration suprasegmental speech information, but not segmental information, such as consonants. The rate of stimulation could also be perceived as pitch, discriminated at different electrode sites along the cochlea and discriminated for stimuli across electrodes. 6. Place pitch could be scaled according to the site of stimulation in the cochlea so that a frequency scale was preserved and it also had a different quality from rate pitch and was described as tonality. Place pitch could also be discriminated for the shorter durations (25 ms) required for identifying consonants. 7. The inaugural speech processing strategy encoded the second formant frequencies (concentrations of frequency energy in the mid frequency range of most importance for speech intelligibility) as place of stimulation, the voicing frequency as rate of stimulation and the intensity as current level. Our further speech processing strategies have extracted additional frequency information and coded this as place of stimulation

  3. Epidural Auditory Event-Related Potentials in the Rat to Frequency and duration Deviants: Evidence of Mismatch Negativity?

    OpenAIRE

    TamoNakamura; WilliamRFulham

    2011-01-01

    The capacity of the human brain to detect deviance in the acoustic environment pre-attentively is reflected in a brain event-related potential (ERP), mismatch negativity (MMN). MMN is observed in response to the presentation of rare oddball sounds that deviate from an otherwise regular pattern of frequent background standard sounds. While the primate and cat auditory cortex (AC) exhibit MMN-like activity, it is unclear whether the rodent AC produces a deviant response that reflects deviance d...

  4. Auditory Discrimination and Auditory Sensory Behaviours in Autism Spectrum Disorders

    Science.gov (United States)

    Jones, Catherine R. G.; Happe, Francesca; Baird, Gillian; Simonoff, Emily; Marsden, Anita J. S.; Tregay, Jenifer; Phillips, Rebecca J.; Goswami, Usha; Thomson, Jennifer M.; Charman, Tony

    2009-01-01

    It has been hypothesised that auditory processing may be enhanced in autism spectrum disorders (ASD). We tested auditory discrimination ability in 72 adolescents with ASD (39 childhood autism; 33 other ASD) and 57 IQ and age-matched controls, assessing their capacity for successful discrimination of the frequency, intensity and duration…

  5. 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. PMID:25726291

  6. Expression of amyloid-β in mouse cochlear hair cells causes an early-onset auditory defect in high-frequency sound perception.

    Science.gov (United States)

    Omata, Yasuhiro; Tharasegaran, Suganya; Lim, Young-Mi; Yamasaki, Yasutoyo; Ishigaki, Yasuhito; Tatsuno, Takanori; Maruyama, Mitsuo; Tsuda, Leo

    2016-03-01

    Increasing evidence indicates that defects in the sensory system are highly correlated with age-related neurodegenerative diseases, including Alzheimer's disease (AD). This raises the possibility that sensory cells possess some commonalities with neurons and may provide a tool for studying AD. The sensory system, especially the auditory system, has the advantage that depression in function over time can easily be measured with electrophysiological methods. To establish a new mouse AD model that takes advantage of this benefit, we produced transgenic mice expressing amyloid-β (Aβ), a causative element for AD, in their auditory hair cells. Electrophysiological assessment indicated that these mice had hearing impairment, specifically in high-frequency sound perception (>32 kHz), at 4 months after birth. Furthermore, loss of hair cells in the basal region of the cochlea, which is known to be associated with age-related hearing loss, appeared to be involved in this hearing defect. Interestingly, overexpression of human microtubule-associated protein tau, another factor in AD development, synergistically enhanced the Aβ-induced hearing defects. These results suggest that our new system reflects some, if not all, aspects of AD progression and, therefore, could complement the traditional AD mouse model to monitor Aβ-induced neuronal dysfunction quantitatively over time. PMID:26959388

  7. Finding your mate at a cocktail party: frequency separation promotes auditory stream segregation of concurrent voices in multi-species frog choruses.

    Directory of Open Access Journals (Sweden)

    Vivek Nityananda

    Full Text Available Vocal communication in crowded social environments is a difficult problem for both humans and nonhuman animals. Yet many important social behaviors require listeners to detect, recognize, and discriminate among signals in a complex acoustic milieu comprising the overlapping signals of multiple individuals, often of multiple species. Humans exploit a relatively small number of acoustic cues to segregate overlapping voices (as well as other mixtures of concurrent sounds, like polyphonic music. By comparison, we know little about how nonhuman animals are adapted to solve similar communication problems. One important cue enabling source segregation in human speech communication is that of frequency separation between concurrent voices: differences in frequency promote perceptual segregation of overlapping voices into separate "auditory streams" that can be followed through time. In this study, we show that frequency separation (ΔF also enables frogs to segregate concurrent vocalizations, such as those routinely encountered in mixed-species breeding choruses. We presented female gray treefrogs (Hyla chrysoscelis with a pulsed target signal (simulating an attractive conspecific call in the presence of a continuous stream of distractor pulses (simulating an overlapping, unattractive heterospecific call. When the ΔF between target and distractor was small (e.g., ≤3 semitones, females exhibited low levels of responsiveness, indicating a failure to recognize the target as an attractive signal when the distractor had a similar frequency. Subjects became increasingly more responsive to the target, as indicated by shorter latencies for phonotaxis, as the ΔF between target and distractor increased (e.g., ΔF = 6-12 semitones. These results support the conclusion that gray treefrogs, like humans, can exploit frequency separation as a perceptual cue to segregate concurrent voices in noisy social environments. The ability of these frogs to segregate

  8. Tracking the Time Course of Word-Frequency Effects in Auditory Word Recognition with Event-Related Potentials

    Science.gov (United States)

    Dufour, Sophie; Brunelliere, Angele; Frauenfelder, Ulrich H.

    2013-01-01

    Although the word-frequency effect is one of the most established findings in spoken-word recognition, the precise processing locus of this effect is still a topic of debate. In this study, we used event-related potentials (ERPs) to track the time course of the word-frequency effect. In addition, the neighborhood density effect, which is known to…

  9. Microglia Modulate Wiring of the Embryonic Forebrain

    Directory of Open Access Journals (Sweden)

    Paola Squarzoni

    2014-09-01

    Full Text Available Dysfunction of microglia, the tissue macrophages of the brain, has been associated with the etiology of several neuropsychiatric disorders. Consistently, microglia have been shown to regulate neurogenesis and synaptic maturation at perinatal and postnatal stages. However, microglia invade the brain during mid-embryogenesis and thus could play an earlier prenatal role. Here, we show that embryonic microglia, which display a transiently uneven distribution, regulate the wiring of forebrain circuits. Using multiple mouse models, including cell-depletion approaches and cx3cr1−/−, CR3−/−, and DAP12−/− mutants, we find that perturbing microglial activity affects the outgrowth of dopaminergic axons in the forebrain and the laminar positioning of subsets of neocortical interneurons. Since defects in both dopamine innervation and cortical networks have been linked to neuropsychiatric diseases, our study provides insights into how microglial dysfunction can impact forebrain connectivity and reveals roles for immune cells during normal assembly of brain circuits.

  10. State-dependent and cell type-specific temporal processing in auditory thalamocortical circuit

    OpenAIRE

    Shuzo Sakata

    2016-01-01

    Ongoing spontaneous activity in cortical circuits defines cortical states, but it still remains unclear how cortical states shape sensory processing across cortical laminae and what type of response properties emerge in the cortex. Recording neural activity from the auditory cortex (AC) and medial geniculate body (MGB) simultaneously with electrical stimulations of the basal forebrain (BF) in urethane-anesthetized rats, we investigated state-dependent spontaneous and auditory-evoked activitie...

  11. A critical period for auditory thalamocortical connectivity

    DEFF Research Database (Denmark)

    Rinaldi Barkat, Tania; Polley, Daniel B; Hensch, Takao K

    2011-01-01

    connectivity by in vivo recordings and day-by-day voltage-sensitive dye imaging in an acute brain slice preparation. Passive tone-rearing modified response strength and topography in mouse primary auditory cortex (A1) during a brief, 3-d window, but did not alter tonotopic maps in the thalamus. Gene......-targeted deletion of a forebrain-specific cell-adhesion molecule (Icam5) accelerated plasticity in this critical period. Consistent with its normal role of slowing spinogenesis, loss of Icam5 induced precocious stubby spine maturation on pyramidal cell dendrites in neocortical layer 4 (L4), identifying a primary...

  12. Auditory, Somatosensory, and Multisensory Insular Cortex in the Rat

    OpenAIRE

    Rodgers, Krista M.; Benison, Alexander M.; Klein, Andrea; Barth, Daniel S.

    2008-01-01

    Compared with other areas of the forebrain, the function of insular cortex is poorly understood. This study examined the unisensory and multisensory function of the rat insula using high-resolution, whole-hemisphere, epipial evoked potential mapping. We found the posterior insula to contain distinct auditory and somatotopically organized somatosensory fields with an interposed and overlapping region capable of integrating these sensory modalities. Unisensory and multisensory responses were un...

  13. Adult Mouse Basal Forebrain Harbors Two Distinct Cholinergic Populations Defined By Their Electrophysiology

    Directory of Open Access Journals (Sweden)

    Jorge P Golowasch

    2012-05-01

    Full Text Available We performed whole-cell recordings from basal forebrain cholinergic neurons in transgenic mice expressing enhanced green fluorescent protein under the control of choline acetyltransferase promoter. Basal forebrain cholinergic neurons can be differentiated into two electrophysiologically identifiable subtypes: early and late firing neurons. Early firing neurons (70% are more excitable, show prominent spike frequency adaptation and more susceptible to depolarization blockade, a phenomenon characterized by complete silencing of the neuron following initial action potentials. Late firing neurons (30%, albeit being less excitable, could maintain a tonic discharge at low frequencies. In voltage clamp analysis, we have shown that early firing neurons have a higher density of low voltage activated calcium currents. These two cholinergic cell populations might be involved in distinct functions: the early firing group being more suitable for phasic changes in cortical acetylcholine release associated with attention while the late firing neurons could support general arousal by maintaining tonic acetylcholine level.

  14. Genes involved in forebrain development in the zebrafish, Danio rerio.

    Science.gov (United States)

    Heisenberg, C P; Brand, M; Jiang, Y J; Warga, R M; Beuchle, D; van Eeden, F J; Furutani-Seiki, M; Granato, M; Haffter, P; Hammerschmidt, M; Kane, D A; Kelsh, R N; Mullins, M C; Odenthal, J; Nusslein-Volhard, C

    1996-12-01

    We identified four zebrafish mutants with defects in forebrain induction and patterning during embryogenesis. The four mutants define three genes: masterblind (mbl), silberblick (slb), and knollnase (kas). In mbl embryos, the anterior forebrain acquires posterior forebrain characteristics: anterior structures such as the eyes, olfactory placodes and the telencephalon are missing, whereas the epiphysis located in the posterior forebrain is expanded. In slb embryos, the extension of the embryonic axis is initially delayed and eventually followed by a partial fusion of the eyes. Finally, in kas embryos, separation of the telencephalic primordia is incomplete and dorsal midline cells fail to form a differentiated roof plate. Analysis of the mutant phenotypes indicates that we have identified genes essential for the specification of the anterior forebrain (mbl), positioning of the eyes (slb) and differentiation of the roof plate (kas). In an appendix to this study we list mutants showing alterations in the size of the eyes and abnormal differentiation of the lenses. PMID:9007240

  15. Auditory Association Cortex Lesions Impair Auditory Short-Term Memory in Monkeys

    Science.gov (United States)

    Colombo, Michael; D'Amato, Michael R.; Rodman, Hillary R.; Gross, Charles G.

    1990-01-01

    Monkeys that were trained to perform auditory and visual short-term memory tasks (delayed matching-to-sample) received lesions of the auditory association cortex in the superior temporal gyrus. Although visual memory was completely unaffected by the lesions, auditory memory was severely impaired. Despite this impairment, all monkeys could discriminate sounds closer in frequency than those used in the auditory memory task. This result suggests that the superior temporal cortex plays a role in auditory processing and retention similar to the role the inferior temporal cortex plays in visual processing and retention.

  16. The Role of Auditory and Kinaesthetic Feedback Mechanisms on Phonatory Stability in Children

    OpenAIRE

    Rathna Kumar, S. B.; Azeem, Suhail; Choudhary, Abhishek Kumar; Prakash, S. G. R.

    2012-01-01

    Auditory feedback plays an important role in phonatory control. When auditory feedback is disrupted, various changes are observed in vocal motor control. Vocal intensity and fundamental frequency (F0) levels tend to increase in response to auditory masking. Because of the close reflexive links between the auditory and phonatory systems, it is likely that phonatory stability may be disrupted when auditory feedback is disrupted or altered. However, studies on phonatory stability under auditory ...

  17. Neural Correlates of an Auditory Afterimage in Primary Auditory Cortex

    OpenAIRE

    Noreña, A. J.; Eggermont, J. J.

    2003-01-01

    The Zwicker tone (ZT) is defined as an auditory negative afterimage, perceived after the presentation of an appropriate inducer. Typically, a notched noise (NN) with a notch width of 1/2 octave induces a ZT with a pitch falling in the frequency range of the notch. The aim of the present study was to find potential neural correlates of the ZT in the primary auditory cortex of ketamine-anesthetized cats. Responses of multiunits were recorded simultaneously with two 8-electrode arrays during 1 s...

  18. Mosaic Subventricular Origins of Forebrain Oligodendrogenesis.

    Science.gov (United States)

    Azim, Kasum; Berninger, Benedikt; Raineteau, Olivier

    2016-01-01

    In the perinatal as well as the adult CNS, the subventricular zone (SVZ) of the forebrain is the largest and most active source of neural stem cells (NSCs) that generates neurons and oligodendrocytes (OLs), the myelin forming cells of the CNS. Recent advances in the field are beginning to shed light regarding SVZ heterogeneity, with the existence of spatially segregated microdomains that are intrinsically biased to generate phenotypically distinct neuronal populations. Although most research has focused on this regionalization in the context of neurogenesis, newer findings underline that this also applies for the genesis of OLs under the control of specific patterning molecules. In this mini review, we discuss the origins as well as the mechanisms that induce and maintain SVZ regionalization. These come in the flavor of specific signaling ligands and subsequent initiation of transcriptional networks that provide a basis for subdividing the SVZ into distinct lineage-specific microdomains. We further emphasize canonical Wnts and FGF2 as essential signaling pathways for the regional genesis of OL progenitors from NSCs of the dorsal SVZ. This aspect of NSC biology, which has so far received little attention, may unveil new avenues for appropriately recruiting NSCs in demyelinating diseases. PMID:27047329

  19. Mosaic subventricular origins of forebrain oligodendroglia

    Directory of Open Access Journals (Sweden)

    Kasum eAzim

    2016-03-01

    Full Text Available In the perinatal as well as the adult CNS, the subventricular zone (SVZ of the forebrain is the largest and most active source of neural stem cells (NSCs that generates neurons and oligodendrocytes (OLs, the myelin forming cells of the CNS. Recent advances in the field are beginning to shed light regarding SVZ heterogeneity, with the existence of spatially segregated microdomains that are intrinsically biased to generate phenotypically distinct neuronal populations. Although most research has focused on this regionalization in the context of neurogenesis, newer findings underline that this also applies for the genesis of OLs under the control of specific patterning molecules. In this mini review, we discuss the origins as well as the mechanisms that induce and maintain SVZ regionalization. These come in the flavor of specific signaling ligands and subsequent initiation of transcriptional networks that provide a basis for subdividing the SVZ into distinct lineage-specific microdomains. We further emphasize canonical Wnt and FGF2 as essential signaling pathways for the regional genesis of OL progenitors from NSCs of the dorsal SVZ. This aspect of NSC biology, which has so far received little attention, may unveil new avenues for appropriately recruiting NSCs in demyelinating diseases.

  20. Auditory Hallucinations in Acute Stroke

    Directory of Open Access Journals (Sweden)

    Yair Lampl

    2005-01-01

    Full Text Available Auditory hallucinations are uncommon phenomena which can be directly caused by acute stroke, mostly described after lesions of the brain stem, very rarely reported after cortical strokes. The purpose of this study is to determine the frequency of this phenomenon. In a cross sectional study, 641 stroke patients were followed in the period between 1996–2000. Each patient underwent comprehensive investigation and follow-up. Four patients were found to have post cortical stroke auditory hallucinations. All of them occurred after an ischemic lesion of the right temporal lobe. After no more than four months, all patients were symptom-free and without therapy. The fact the auditory hallucinations may be of cortical origin must be taken into consideration in the treatment of stroke patients. The phenomenon may be completely reversible after a couple of months.

  1. 基于听觉神经同步振荡网络的时频结构描述方法%Novel Method for Time-frequency Structure Description Based on Synchronized Oscillatory Network of Auditory Nerve Fiber

    Institute of Scientific and Technical Information of China (English)

    李允公; 张金萍; 戴丽; 张占一

    2012-01-01

    人类听觉系统具有优良的非平稳信号分析能力,在听觉系统中,由耳蜗基底膜对信号进行类似于带通滤波的时频分解,并由内毛细胞、传入神经和听觉中枢的神经网络对时频分解结果逐步进行特征信息提取和压缩.鉴于此,参照Wang-Brown模型,建立一种可描述信号时频结构特征的听觉模型,该模型包括基底膜、内毛细胞、中级听觉和听觉中枢等子模型,听觉中枢模型由单层听神经振荡网络构成.略去Wang-Brown模型中随机项和侧抑制项,简化内毛细胞模型,设计听神经元的活跃准则和神经元间的联接方式.信号经基底膜、内毛细胞和中级听觉模型处理后,由听神经振荡网络进行信息综合,使得信号中时频结构相似的区域所对应的听神经元进行同步振荡,从而可利用同步振荡神经元的分布情况描述信号的时频结构.进行故障转子升降速试验和风力发电增速机稳速运行试验,试验所得信号的分析结果表明,所建模型能够有效描述信号的时频结构特征及其变化情况,对信号的瞬态变化较为敏感,且数据量相对较小,易于智能识别.%The human auditory system possesses excellent capability to analysis non-stationary signal. In auditory system, before a signal is recognized by the auditory cortex, it is sequentially processed by the basilar membrane, which can be seen as a bandpass filterbank, and other elements in auditory system. Therefore, to describe the structure features of signal in time-frequency space, an auditory model is proposed based on Wang-Brown model and the auditory nerve fiber oscillatory network with single layer. This model consists of basilar membrane, inner hair cells, middle auditory stage and auditory cortex, and the auditory cortex model is a single layer auditory nerve fiber oscillatory network. According to the characteristic of mechanical vibration signal, the random term and lateral inhibitor in Wang

  2. Lhx2 Regulates the Development of the Forebrain Hem System

    Science.gov (United States)

    Roy, Achira; Gonzalez-Gomez, Miriam; Pierani, Alessandra; Meyer, Gundela; Tole, Shubha

    2014-01-01

    Early brain development is regulated by the coordinated actions of multiple signaling centers at key boundaries between compartments. Three telencephalic midline structures are in a position to play such roles in forebrain patterning: The cortical hem, the septum, and the thalamic eminence at the diencephalic–telencephalic boundary. These structures express unique complements of signaling molecules, and they also produce distinct populations of Cajal–Retzius cells, which are thought to act as “mobile patterning units,” migrating tangentially to cover the telencephalic surface. We show that these 3 structures require the transcription factor Lhx2 to delimit their extent. In the absence of Lhx2 function, all 3 structures are greatly expanded, and the Cajal–Retzius cell population is dramatically increased. We propose that the hem, septum, and thalamic eminence together form a “forebrain hem system” that defines and regulates the formation of the telencephalic midline. Disruptions in the forebrain hem system may be implicated in severe brain malformations such as holoprosencephaly. Lhx2 functions as a central regulator of this system's development. Since all components of the forebrain hem system have been identified across several vertebrate species, the mechanisms that regulate them may have played a fundamental role in driving key aspects of forebrain evolution. PMID:23307637

  3. Spectrotemporal resolution tradeoff in auditory processing as revealed by human auditory brainstem responses and psychophysical indices.

    Science.gov (United States)

    Bidelman, Gavin M; Syed Khaja, Ameenuddin

    2014-06-20

    Auditory filter theory dictates a physiological compromise between frequency and temporal resolution of cochlear signal processing. We examined neurophysiological correlates of these spectrotemporal tradeoffs in the human auditory system using auditory evoked brain potentials and psychophysical responses. Temporal resolution was assessed using scalp-recorded auditory brainstem responses (ABRs) elicited by paired clicks. The inter-click interval (ICI) between successive pulses was parameterized from 0.7 to 25 ms to map ABR amplitude recovery as a function of stimulus spacing. Behavioral frequency difference limens (FDLs) and auditory filter selectivity (Q10 of psychophysical tuning curves) were obtained to assess relations between behavioral spectral acuity and electrophysiological estimates of temporal resolvability. Neural responses increased monotonically in amplitude with increasing ICI, ranging from total suppression (0.7 ms) to full recovery (25 ms) with a temporal resolution of ∼3-4 ms. ABR temporal thresholds were correlated with behavioral Q10 (frequency selectivity) but not FDLs (frequency discrimination); no correspondence was observed between Q10 and FDLs. Results suggest that finer frequency selectivity, but not discrimination, is associated with poorer temporal resolution. The inverse relation between ABR recovery and perceptual frequency tuning demonstrates a time-frequency tradeoff between the temporal and spectral resolving power of the human auditory system. PMID:24793771

  4. Reliability of low-frequency auditory stimulation studies associated with technetium-99m hexamethylpropylene amine oxime single-photon emission tomography

    International Nuclear Information System (INIS)

    Development of auditory stimulation tests associated with single-photon emission tomography (SPET) shows evidence of variations in perfusion related to the stimuli. Three brain SPET examinations with technetium-99m hexamethylpropylene amine oxime were performed on eight right-handed adults with normal hearing, the first one without stimulation and the other two associated with a 500-Hz/30-dB stimulation of the right ear. Temporal regions of interest covering auditory areas, as well as parietal ones (internal control), were drawn on three successive coronal slices. A cortico-cerebellar index R was calculated, and the variation in activity was defined for each subject using the ratio Rpoststimulation - Rprestimulation/Rprestumulation. A significant increase in the temporal cortex count occurred in all subjects. This increase was bilateral, except for one subject in whom it was not significant on the right side. This result recurred during the second stimulation study. Overall the response of the left temporal cortex was stronger, although the asymmetry was not significant. The asymmetry repeated itself after each stimulation. The perfursion response is globally reliable in our study. We must ascertainhow sensitive this test is with regard to deaf adults and adults with normal hearing before extending its use to children. (orig.)

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  11. Recent experience modulates forebrain gene-expression in response to mate-choice cues in European starlings.

    Science.gov (United States)

    Sockman, Keith W; Gentner, Timothy Q; Ball, Gregory F

    2002-12-01

    Mate-choice decisions can be experience dependent, but we know little about how the brain processes stimuli that release such decisions. Female European starlings (Sturnus vulgaris) prefer males with long-bout songs over males with short-bout songs, and show higher expression of the immediate early gene (IEG) ZENK in the auditory forebrain when exposed to long-bout songs than when exposed to short-bout songs. We exposed female starlings to a short-day photoperiod for one of three durations and then, on an increased photophase, exposed them to one week of long-bout or short-bout song experience. We then examined their IEG response to novel long-bout versus novel short-bout songs by quantifying ZENK protein in two song-processing areas: the caudo-medial hyperstriatum ventrale and the caudo-medial neostriatum. ZENK expression in both areas increased with tenure on short-day photoperiods, suggesting that short days sensitize females to song. The ZENK response bias toward long-bout songs was greater in females with long-bout experience than in females with short-bout experience, indicating that the forebrain response bias toward a preferred trait depends on recent experience with that category of trait. This surprising level of neuroplasticity is immediately relevant to the natural history and fitness of the organism, and may underlie a mechanism for optimizing mate-choice criteria amidst locally variable distributions of secondary sexual characteristics. PMID:12495492

  12. Task-Phase-Specific Dynamics of Basal Forebrain Neuronal Ensembles

    Directory of Open Access Journals (Sweden)

    Douglas A Nitz

    2014-09-01

    Full Text Available Cortically projecting basal forebrain neurons play a critical role in learning and attention, and their degeneration accompanies age-related impairments in cognition. Despite the impressive anatomical and cell-type complexity of this system, currently available data suggest that basal forebrain neurons lack complexity in their response fields, with activity primarily reflecting only macro-level brain states such as sleep and wake, onset of relevant stimuli and/or reward obtainment. The current study examined the spiking activity of basal forebrain neuron populations across multiple phases of a selective attention task, addressing, in particular, the issue of complexity in ensemble firing patterns across time. Clustering techniques applied to the full population revealed a large number of distinct categories of task-phase-specific activity patterns. Unique population firing-rate vectors defined each task phase and most categories of task-phase-specific firing had counterparts with opposing firing patterns. An analogous set of task-phase-specific firing patterns was also observed in a population of posterior parietal cortex neurons. Thus, consistent with the known anatomical complexity, basal forebrain population dynamics are capable of differentially modulating their cortical targets according to the unique sets of environmental stimuli, motor requirements, and cognitive processes associated with different task phases.

  13. Forebrain Mechanisms of Nociception and Pain: Analysis through Imaging

    Science.gov (United States)

    Casey, Kenneth L.

    1999-07-01

    Pain is a unified experience composed of interacting discriminative, affective-motivational, and cognitive components, each of which is mediated and modulated through forebrain mechanisms acting at spinal, brainstem, and cerebral levels. The size of the human forebrain in relation to the spinal cord gives anatomical emphasis to forebrain control over nociceptive processing. Human forebrain pathology can cause pain without the activation of nociceptors. Functional imaging of the normal human brain with positron emission tomography (PET) shows synaptically induced increases in regional cerebral blood flow (rCBF) in several regions specifically during pain. We have examined the variables of gender, type of noxious stimulus, and the origin of nociceptive input as potential determinants of the pattern and intensity of rCBF responses. The structures most consistently activated across genders and during contact heat pain, cold pain, cutaneous laser pain or intramuscular pain were the contralateral insula and anterior cingulate cortex, the bilateral thalamus and premotor cortex, and the cerebellar vermis. These regions are commonly activated in PET studies of pain conducted by other investigators, and the intensity of the brain rCBF response correlates parametrically with perceived pain intensity. To complement the human studies, we developed an animal model for investigating stimulus-induced rCBF responses in the rat. In accord with behavioral measures and the results of human PET, there is a progressive and selective activation of somatosensory and limbic system structures in the brain and brainstem following the subcutaneous injection of formalin. The animal model and human PET studies should be mutually reinforcing and thus facilitate progress in understanding forebrain mechanisms of normal and pathological pain.

  14. Auditory Efferent System Modulates Mosquito Hearing.

    Science.gov (United States)

    Andrés, Marta; Seifert, Marvin; Spalthoff, Christian; Warren, Ben; Weiss, Lukas; Giraldo, Diego; Winkler, Margret; Pauls, Stephanie; Göpfert, Martin C

    2016-08-01

    The performance of vertebrate ears is controlled by auditory efferents that originate in the brain and innervate the ear, synapsing onto hair cell somata and auditory afferent fibers [1-3]. Efferent activity can provide protection from noise and facilitate the detection and discrimination of sound by modulating mechanical amplification by hair cells and transmitter release as well as auditory afferent action potential firing [1-3]. Insect auditory organs are thought to lack efferent control [4-7], but when we inspected mosquito ears, we obtained evidence for its existence. Antibodies against synaptic proteins recognized rows of bouton-like puncta running along the dendrites and axons of mosquito auditory sensory neurons. Electron microscopy identified synaptic and non-synaptic sites of vesicle release, and some of the innervating fibers co-labeled with somata in the CNS. Octopamine, GABA, and serotonin were identified as efferent neurotransmitters or neuromodulators that affect auditory frequency tuning, mechanical amplification, and sound-evoked potentials. Mosquito brains thus modulate mosquito ears, extending the use of auditory efferent systems from vertebrates to invertebrates and adding new levels of complexity to mosquito sound detection and communication. PMID:27476597

  15. Auditory imagery: empirical findings.

    Science.gov (United States)

    Hubbard, Timothy L

    2010-03-01

    The empirical literature on auditory imagery is reviewed. Data on (a) imagery for auditory features (pitch, timbre, loudness), (b) imagery for complex nonverbal auditory stimuli (musical contour, melody, harmony, tempo, notational audiation, environmental sounds), (c) imagery for verbal stimuli (speech, text, in dreams, interior monologue), (d) auditory imagery's relationship to perception and memory (detection, encoding, recall, mnemonic properties, phonological loop), and (e) individual differences in auditory imagery (in vividness, musical ability and experience, synesthesia, musical hallucinosis, schizophrenia, amusia) are considered. It is concluded that auditory imagery (a) preserves many structural and temporal properties of auditory stimuli, (b) can facilitate auditory discrimination but interfere with auditory detection, (c) involves many of the same brain areas as auditory perception, (d) is often but not necessarily influenced by subvocalization, (e) involves semantically interpreted information and expectancies, (f) involves depictive components and descriptive components, (g) can function as a mnemonic but is distinct from rehearsal, and (h) is related to musical ability and experience (although the mechanisms of that relationship are not clear). PMID:20192565

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

    Directory of Open Access Journals (Sweden)

    Henning U Voss

    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.

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

    OpenAIRE

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

    2016-01-01

    Perineuronal nets (PNNs) are specialized extracellular matrix molecules that are associated with the closing of the critical period, among other functions. In the adult brain, PNNs surround specific types of neurons, however the expression of PNNs in the auditory system of the mouse, particularly at the level of the midbrain and forebrain, has not been fully described. In addition, the association of PNNs with excitatory and inhibitory cell types in these structures remains unknown. Therefore...

  18. Fragile Spectral and Temporal Auditory Processing in Adolescents with Autism Spectrum Disorder and Early Language Delay

    Science.gov (United States)

    Boets, Bart; Verhoeven, Judith; Wouters, Jan; Steyaert, Jean

    2015-01-01

    We investigated low-level auditory spectral and temporal processing in adolescents with autism spectrum disorder (ASD) and early language delay compared to matched typically developing controls. Auditory measures were designed to target right versus left auditory cortex processing (i.e. frequency discrimination and slow amplitude modulation (AM)…

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of low...

  20. Lhx2 Regulates the Development of the Forebrain Hem System

    OpenAIRE

    Roy, Achira; Gonzalez-Gomez, Miriam; Pierani, Alessandra; Meyer, Gundela; Tole, Shubha

    2013-01-01

    Early brain development is regulated by the coordinated actions of multiple signaling centers at key boundaries between compartments. Three telencephalic midline structures are in a position to play such roles in forebrain patterning: The cortical hem, the septum, and the thalamic eminence at the diencephalic–telencephalic boundary. These structures express unique complements of signaling molecules, and they also produce distinct populations of Cajal–Retzius cells, which are thought to act as...

  1. Forebrain-independent generation of hyperthermic convulsions in infant rats.

    Science.gov (United States)

    Pospelov, Alexey S; Yukin, Alexey Y; Blumberg, Mark S; Puskarjov, Martin; Kaila, Kai

    2016-01-01

    Febrile seizures are the most common type of convulsive events in children. It is generally assumed that the generalization of these seizures is a result of brainstem invasion by the initial limbic seizure activity. Using precollicular transection in 13-day-old rats to isolate the forebrain from the brainstem, we demonstrate that the forebrain is not required for generation of tonic-clonic convulsions induced by hyperthermia or kainate. Compared with sham-operated littermate controls, latency to onset of convulsions in both models was significantly shorter in pups that had undergone precollicular transection, indicating suppression of the brainstem seizure network by the forebrain in the intact animal. We have shown previously that febrile seizures are precipitated by hyperthermia-induced respiratory alkalosis. Here, we show that triggering of hyperthermia-induced hyperventilation and consequent convulsions in transected animals are blocked by diazepam. The present data suggest that the role of endogenous brainstem activity in triggering tonic-clonic seizures should be re-evaluated in standard experimental models of limbic seizures. Our work sheds new light on the mechanisms that generate febrile seizures in children and, therefore, on how they might be treated. PMID:26547277

  2. Mast cells in the sheep, hedgehog and rat forebrain

    Science.gov (United States)

    MICHALOUDI, HELEN C.; PAPADOPOULOS, GEORGIOS C.

    1999-01-01

    The study was designed to reveal the distribution of various mast cell types in the forebrain of the adult sheep, hedgehog and rat. Based on their histochemical and immunocytochemical characteristics, mast cells were categorised as (1) connective tissue-type mast cells, staining metachromatically purple with the toluidine blue method, or pale red with the Alcian blue/safranin method, (2) mucosal-type or immature mast cells staining blue with the Alcian blue/safranin method and (3) serotonin immunopositive mast cells. All 3 types of brain mast cells in all species studied were located in both white and grey matter, often associated with intraparenchymal blood vessels. Their distribution pattern exhibited interspecies differences, while their number varied considerably not only between species but also between individuals of each species. A distributional left-right asymmetry, with more cells present on the left side, was observed in all species studied but it was most prominent in the sheep brain. In the sheep, mast cells were abundantly distributed in forebrain areas, while in the hedgehog and the rat forebrain, mast cells were less widely distributed and were relatively or substantially fewer in number respectively. A limited number of brain mast cells, in all 3 species, but primarily in the rat, were found to react both immunocytochemically to 5-HT antibody and histochemically with Alcian blue/safranin staining. PMID:10634696

  3. Sound detection by the longfin squid (Loligo pealeii) studied with auditory evoked potentials: sensitivity to low-frequency particle motion and not pressure

    DEFF Research Database (Denmark)

    Mooney, T. Aran; Hanlon, Roger T; Christensen-Dalsgaard, Jakob;

    2010-01-01

    extinguished at all frequencies if (1) water temperatures were less than 8°C, (2) statocysts were ablated, or (3) recording electrodes were placed in locations other than near the statocysts. Both the AEP response characteristics and the range of responses suggest that squid detect sound similarly to most fish......Although hearing has been described for many underwater species, there is much debate regarding if and how cephalopods detect sound. Here we quantify the acoustic sensitivity of the longfin squid (Loligo pealeii) using near-field acoustic and shaker-generated acceleration stimuli. Sound field......, with the statocyst acting as an accelerometer through which squid detect the particle motion component of a sound field. The modality and frequency range indicate that squid probably detect acoustic particle motion stimuli from both predators and prey as well as low-frequency environmental sound signatures that may...

  4. The role of vowel perceptual cues in compensatory responses to perturbations of speech auditory feedback

    OpenAIRE

    Reilly, Kevin J.; Dougherty, Kathleen E.

    2013-01-01

    The perturbation of acoustic features in a speaker's auditory feedback elicits rapid compensatory responses that demonstrate the importance of auditory feedback for control of speech output. The current study investigated whether responses to a perturbation of speech auditory feedback vary depending on the importance of the perturbed feature to perception of the vowel being produced. Auditory feedback of speakers' first formant frequency (F1) was shifted upward by 130 mels in randomly selecte...

  5. Impact of Educational Level on Performance on Auditory Processing Tests.

    Science.gov (United States)

    Murphy, Cristina F B; Rabelo, Camila M; Silagi, Marcela L; Mansur, Letícia L; Schochat, Eliane

    2016-01-01

    Research has demonstrated that a higher level of education is associated with better performance on cognitive tests among middle-aged and elderly people. However, the effects of education on auditory processing skills have not yet been evaluated. Previous demonstrations of sensory-cognitive interactions in the aging process indicate the potential importance of this topic. Therefore, the primary purpose of this study was to investigate the performance of middle-aged and elderly people with different levels of formal education on auditory processing tests. A total of 177 adults with no evidence of cognitive, psychological or neurological conditions took part in the research. The participants completed a series of auditory assessments, including dichotic digit, frequency pattern and speech-in-noise tests. A working memory test was also performed to investigate the extent to which auditory processing and cognitive performance were associated. The results demonstrated positive but weak correlations between years of schooling and performance on all of the tests applied. The factor "years of schooling" was also one of the best predictors of frequency pattern and speech-in-noise test performance. Additionally, performance on the working memory, frequency pattern and dichotic digit tests was also correlated, suggesting that the influence of educational level on auditory processing performance might be associated with the cognitive demand of the auditory processing tests rather than auditory sensory aspects itself. Longitudinal research is required to investigate the causal relationship between educational level and auditory processing skills. PMID:27013958

  6. TASK Channels on Basal Forebrain Cholinergic Neurons Modulate Electrocortical Signatures of Arousal by Histamine

    OpenAIRE

    Vu, Michael T.; Du, Guizhi; Bayliss, Douglas A.; Horner, Richard L.

    2015-01-01

    Basal forebrain cholinergic neurons are the main source of cortical acetylcholine, and their activation by histamine elicits cortical arousal. TWIK-like acid-sensitive K+ (TASK) channels modulate neuronal excitability and are expressed on basal forebrain cholinergic neurons, but the role of TASK channels in the histamine-basal forebrain cholinergic arousal circuit is unknown. We first expressed TASK channel subunits and histamine Type 1 receptors in HEK cells. Application of histamine in vitr...

  7. 40 Hz auditory steady state response to linguistic features of stimuli during auditory hallucinations.

    Science.gov (United States)

    Ying, Jun; Yan, Zheng; Gao, Xiao-rong

    2013-10-01

    The auditory steady state response (ASSR) may reflect activity from different regions of the brain, depending on the modulation frequency used. In general, responses induced by low rates (≤40 Hz) emanate mostly from central structures of the brain, and responses from high rates (≥80 Hz) emanate mostly from the peripheral auditory nerve or brainstem structures. Besides, it was reported that the gamma band ASSR (30-90 Hz) played an important role in working memory, speech understanding and recognition. This paper investigated the 40 Hz ASSR evoked by modulated speech and reversed speech. The speech was Chinese phrase voice, and the noise-like reversed speech was obtained by temporally reversing the speech. Both auditory stimuli were modulated with a frequency of 40 Hz. Ten healthy subjects and 5 patients with hallucination symptom participated in the experiment. Results showed reduction in left auditory cortex response when healthy subjects listened to the reversed speech compared with the speech. In contrast, when the patients who experienced auditory hallucinations listened to the reversed speech, the auditory cortex of left hemispheric responded more actively. The ASSR results were consistent with the behavior results of patients. Therefore, the gamma band ASSR is expected to be helpful for rapid and objective diagnosis of hallucination in clinic. PMID:24142731

  8. 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. PMID:22271265

  9. To modulate and be modulated: estrogenic influences on auditory processing of communication signals within a socio-neuro-endocrine framework.

    Science.gov (United States)

    Yoder, Kathleen M; Vicario, David S

    2012-02-01

    Gonadal hormones modulate behavioral responses to sexual stimuli, and communication signals can also modulate circulating hormone levels. In several species, these combined effects appear to underlie a two-way interaction between circulating gonadal hormones and behavioral responses to socially salient stimuli. Recent work in songbirds has shown that manipulating local estradiol levels in the auditory forebrain produces physiological changes that affect discrimination of conspecific vocalizations and can affect behavior. These studies provide new evidence that estrogens can directly alter auditory processing and indirectly alter the behavioral response to a stimulus. These studies show that: 1) Local estradiol action within an auditory area is necessary for socially relevant sounds to induce normal physiological responses in the brains of both sexes; 2) These physiological effects occur much more quickly than predicted by the classical time-frame for genomic effects; 3) Estradiol action within the auditory forebrain enables behavioral discrimination among socially relevant sounds in males; and 4) Estradiol is produced locally in the male brain during exposure to particular social interactions. The accumulating evidence suggests a socio-neuro-endocrinology framework in which estradiol is essential to auditory processing, is increased by a socially relevant stimulus, acts rapidly to shape perception of subsequent stimuli experienced during social interactions, and modulates behavioral responses to these stimuli. Brain estrogens are likely to function similarly in both songbird sexes because aromatase and estrogen receptors are present in both male and female forebrain. Estrogenic modulation of perception in songbirds and perhaps other animals could fine-tune male advertising signals and female ability to discriminate them, facilitating mate selection by modulating behaviors. PMID:22201281

  10. Binaural processing by the gecko auditory periphery

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Jakob; Tang, Ye Zhong; Carr, Catherine E

    2011-01-01

    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 (around 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...

  11. "First pain" in humans: convergent and specific forebrain responses

    Directory of Open Access Journals (Sweden)

    Tran Tuan D

    2010-11-01

    Full Text Available Abstract Background Brief heat stimuli that excite nociceptors innervated by finely myelinated (Aδ fibers evoke an initial, sharp, well-localized pain ("first pain" that is distinguishable from the delayed, less intense, more prolonged dull pain attributed to nociceptors innervated by unmyelinated (C fibers ("second pain". In the present study, we address the question of whether a brief, noxious heat stimulus that excites cutaneous Aδ fibers activates a distinct set of forebrain structures preferentially in addition to those with similar responses to converging input from C fibers. Heat stimuli at two temperatures were applied to the dorsum of the left hand of healthy volunteers in a functional brain imaging (fMRI paradigm and responses analyzed in a set of volumes of interest (VOI. Results Brief 41°C stimuli were painless and evoked only C fiber responses, but 51°C stimuli were at pain threshold and preferentially evoked Aδ fiber responses. Most VOI responded to both intensities of stimulation. However, within volumes of interest, a contrast analysis and comparison of BOLD response latencies showed that the bilateral anterior insulae, the contralateral hippocampus, and the ipsilateral posterior insula were preferentially activated by painful heat stimulation that excited Aδ fibers. Conclusions These findings show that two sets of forebrain structures mediate the initial sharp pain evoked by brief cutaneous heat stimulation: those responding preferentially to the brief stimulation of Aδ heat nociceptors and those with similar responses to converging inputs from the painless stimulation of C fibers. Our results suggest a unique and specific physiological basis, at the forebrain level, for the "first pain" sensation that has long been attributed to Aδ fiber stimulation and support the concept that both specific and convergent mechanisms act concurrently to mediate pain.

  12. Visualization of the medial forebrain bundle using diffusion tensor imaging

    Directory of Open Access Journals (Sweden)

    Ardian Hana

    2015-10-01

    Full Text Available Diffusion tensor imaging is a technique that enables physicians the portrayal of white matter tracts in vivo. We used this technique in order to depict the medial forebrain bundle in 15 consecutive patients between 2012 and 2015. Men and women of all ages were included. There were 6 women and 9 men. The mean age was 58,6 years (39-77. Nine patients were candidates for an eventual deep brain stimulation. Eight of them suffered from Parkinson`s disease and one had multiple sclerosis. The remaining 6 patients suffered from different lesions which were situated in the frontal lobe. These were 2 metastasis, 2 meningiomas, 1 cerebral bleeding and 1 glioblastoma. We used a 3DT1-sequence for the navigation. Furthermore T2- and DTI- sequences were performed. The FOV was 200 x 200 mm², slice thickness 2 mm, and an acquisition matrix of 96 x 96 yielding nearly isotropic voxels of 2 x 2 x 2 mm. 3-Tesla-MRI was carried out strictly axial using 32 gradient directions and one b0-image. We used Echo-Planar-Imaging (EPI and ASSET parallel imaging with an acceleration factor of 2. b-value was 800 s/mm². The maximal angle was 50°. Additional scanning time was less than 9 minutes. We were able to visualize the medial forebrain bundle in 12 of our patients bilaterally and in the remaining 3 patients we depicted the medial forebrain bundle on one side. It was the contralateral side of the lesion. These were 2 meningiomas and one metastasis. Portrayal of the medial forebrain bundle is possible for everyday routine for neurosurgical interventions. As part of the reward circuitry it might be of substantial importance for neurosurgeons during deep brain stimulation in patients with psychiatric disorders. Furthermore it might explain at a certain extent character changes in patients with lesions in the frontal lobe. Surgery in this part of the brain should always take the preservation of this white matter tract into account.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Auditory Integration Training

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    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.

  15. Basal forebrain atrophy correlates with amyloid β burden in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Georg M Kerbler

    2015-01-01

    Full Text Available The brains of patients suffering from Alzheimer's disease (AD have three classical pathological hallmarks: amyloid-beta (Aβ plaques, tau tangles, and neurodegeneration, including that of cholinergic neurons of the basal forebrain. However the relationship between Aβ burden and basal forebrain degeneration has not been extensively studied. To investigate this association, basal forebrain volumes were determined from magnetic resonance images of controls, subjects with amnestic mild cognitive impairment (aMCI and AD patients enrolled in the longitudinal Alzheimer's Disease Neuroimaging Initiative (ADNI and Australian Imaging, Biomarkers and Lifestyle (AIBL studies. In the AIBL cohort, these volumes were correlated within groups to neocortical gray matter retention of Pittsburgh compound B (PiB from positron emission tomography images as a measure of Aβ load. The basal forebrain volumes of AD and aMCI subjects were significantly reduced compared to those of control subjects. Anterior basal forebrain volume was significantly correlated to neocortical PiB retention in AD subjects and aMCI subjects with high Aβ burden, whereas posterior basal forebrain volume was significantly correlated to neocortical PiB retention in control subjects with high Aβ burden. Therefore this study provides new evidence for a correlation between neocortical Aβ accumulation and basal forebrain degeneration. In addition, cluster analysis showed that subjects with a whole basal forebrain volume below a determined cut-off value had a 7 times higher risk of having a worse diagnosis within ~18 months.

  16. Dcc regulates asymmetric outgrowth of forebrain neurons in zebrafish.

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    Jingxia Gao

    Full Text Available The guidance receptor DCC (deleted in colorectal cancer ortholog UNC-40 regulates neuronal asymmetry development in Caenorhabditis elegans, but it is not known whether DCC plays a role in the specification of neuronal polarity in vertebrates. To examine the roles of DCC in neuronal asymmetry regulation in vertebrates, we studied zebrafish anterior dorsal telencephalon (ADt neuronal axons. We generated transgenic zebrafish animals expressing the photo-convertible fluorescent protein Kaede in ADt neurons and then photo-converted Kaede to label specifically the ADt neuron axons. We found that ADt axons normally project ventrally. Knock down of Dcc function by injecting antisense morpholino oligonucleotides caused the ADt neurons to project axons dorsally. To examine the axon projection pattern of individual ADt neurons, we labeled single ADt neurons using a forebrain-specific promoter to drive fluorescent protein expression. We found that individual ADt neurons projected axons dorsally or formed multiple processes after morpholino knock down of Dcc function. We further found that knock down of the Dcc ligand, Netrin1, also caused ADt neurons to project axons dorsally. Knockdown of Neogenin1, a guidance receptor closely related to Dcc, enhanced the formation of aberrant dorsal axons in embryos injected with Dcc morpholino. These experiments provide the first evidence that Dcc regulates polarized axon initiation and asymmetric outgrowth of forebrain neurons in vertebrates.

  17. Overriding auditory attentional capture

    OpenAIRE

    Dalton, Polly; Lavie, Nilli

    2007-01-01

    Attentional capture by color singletons during shape search can be eliminated when the target is not a feature singleton (Bacon & Egeth, 1994). This suggests that a "singleton detection" search strategy must be adopted for attentional capture to occur. Here we find similar effects on auditory attentional capture. Irrelevant high-intensity singletons interfered with an auditory search task when the target itself was also a feature singleton. However, singleton interference was eliminated when ...

  18. [Central auditory prosthesis].

    Science.gov (United States)

    Lenarz, T; Lim, H; Joseph, G; Reuter, G; Lenarz, M

    2009-06-01

    Deaf patients with severe sensory hearing loss can benefit from a cochlear implant (CI), which stimulates the auditory nerve fibers. However, patients who do not have an intact auditory nerve cannot benefit from a CI. The majority of these patients are neurofibromatosis type 2 (NF2) patients who developed neural deafness due to growth or surgical removal of a bilateral acoustic neuroma. The only current solution is the auditory brainstem implant (ABI), which stimulates the surface of the cochlear nucleus in the brainstem. Although the ABI provides improvement in environmental awareness and lip-reading capabilities, only a few NF2 patients have achieved some limited open set speech perception. In the search for alternative procedures our research group in collaboration with Cochlear Ltd. (Australia) developed a human prototype auditory midbrain implant (AMI), which is designed to electrically stimulate the inferior colliculus (IC). The IC has the potential as a new target for an auditory prosthesis as it provides access to neural projections necessary for speech perception as well as a systematic map of spectral information. In this paper the present status of research and development in the field of central auditory prostheses is presented with respect to technology, surgical technique and hearing results as well as the background concepts of ABI and AMI. PMID:19517084

  19. Formal auditory training in adult hearing aid users

    Directory of Open Access Journals (Sweden)

    Daniela Gil

    2010-01-01

    Full Text Available INTRODUCTION: Individuals with sensorineural hearing loss are often able to regain some lost auditory function with the help of hearing aids. However, hearing aids are not able to overcome auditory distortions such as impaired frequency resolution and speech understanding in noisy environments. The coexistence of peripheral hearing loss and a central auditory deficit may contribute to patient dissatisfaction with amplification, even when audiological tests indicate nearly normal hearing thresholds. OBJECTIVE: This study was designed to validate the effects of a formal auditory training program in adult hearing aid users with mild to moderate sensorineural hearing loss. METHODS: Fourteen bilateral hearing aid users were divided into two groups: seven who received auditory training and seven who did not. The training program was designed to improve auditory closure, figure-to-ground for verbal and nonverbal sounds and temporal processing (frequency and duration of sounds. Pre- and post-training evaluations included measuring electrophysiological and behavioral auditory processing and administration of the Abbreviated Profile of Hearing Aid Benefit (APHAB self-report scale. RESULTS: The post-training evaluation of the experimental group demonstrated a statistically significant reduction in P3 latency, improved performance in some of the behavioral auditory processing tests and higher hearing aid benefit in noisy situations (p-value < 0,05. No changes were noted for the control group (p-value <0,05. CONCLUSION: The results demonstrated that auditory training in adult hearing aid users can lead to a reduction in P3 latency, improvements in sound localization, memory for nonverbal sounds in sequence, auditory closure, figure-to-ground for verbal sounds and greater benefits in reverberant and noisy environments.

  20. Auditory Discrimination Learning: Role of Working Memory.

    Science.gov (United States)

    Zhang, Yu-Xuan; Moore, David R; Guiraud, Jeanne; Molloy, Katharine; Yan, Ting-Ting; Amitay, Sygal

    2016-01-01

    Perceptual training is generally assumed to improve perception by modifying the encoding or decoding of sensory information. However, this assumption is incompatible with recent demonstrations that transfer of learning can be enhanced by across-trial variation of training stimuli or task. Here we present three lines of evidence from healthy adults in support of the idea that the enhanced transfer of auditory discrimination learning is mediated by working memory (WM). First, the ability to discriminate small differences in tone frequency or duration was correlated with WM measured with a tone n-back task. Second, training frequency discrimination around a variable frequency transferred to and from WM learning, but training around a fixed frequency did not. The transfer of learning in both directions was correlated with a reduction of the influence of stimulus variation in the discrimination task, linking WM and its improvement to across-trial stimulus interaction in auditory discrimination. Third, while WM training transferred broadly to other WM and auditory discrimination tasks, variable-frequency training on duration discrimination did not improve WM, indicating that stimulus variation challenges and trains WM only if the task demands stimulus updating in the varied dimension. The results provide empirical evidence as well as a theoretic framework for interactions between cognitive and sensory plasticity during perceptual experience. PMID:26799068

  1. Substitution of natural sensory input by artificial neurostimulation of an amputated trigeminal nerve does not prevent the degeneration of basal forebrain cholinergic circuits projecting to the somatosensory cortex

    Directory of Open Access Journals (Sweden)

    Fivos Panetsos

    2014-11-01

    Full Text Available Peripheral deafferentation downregulates acetylcholine (ACh synthesis in sensory cortices. However the responsible neural circuits and processes are not known. We irreversibly transected the rat infraorbital nerve and implanted neuroprosthetic microdevices for proximal stump stimulation, and assessed cytochrome-oxidase and choline- acetyl-transferase (ChAT in somatosensory, auditory and visual cortices; estimated the number and density of ACh-neurons in the magnocellular basal nucleus (MBN; and localized down-regulated ACh-neurons in basal forebrain using retrograde labeling from deafferented cortices. Here we show that nerve transection, causes down regulation of MBN cholinergic neurons. Stimulation of the cut nerve reverses the metabolic decline but does not affect the decrease in cholinergic fibers in cortex or cholinergic neurons in basal forebrain. Artifical stimulation of the nerve also has no affect of ACh-innervation of other cortices. Cortical ChAT depletion is due to loss of corticopetal MBN ChAT-expressing neurons. MBN ChAT downregulation is not due to decrease neither of afferent activity nor to failure of trophic support. Basalocortical ACh circuits are sensory specific, ACh is provided to each sensory cortex "on demand" by dedicated circuits. Our data support the existence of a modality-specific cortex-MBN-cortex circuit for cognitive information processing.

  2. Spatial auditory processing in pinnipeds

    Science.gov (United States)

    Holt, Marla M.

    Given the biological importance of sound for a variety of activities, pinnipeds must be able to obtain spatial information about their surroundings thorough acoustic input in the absence of other sensory cues. The three chapters of this dissertation address spatial auditory processing capabilities of pinnipeds in air given that these amphibious animals use acoustic signals for reproduction and survival on land. Two chapters are comparative lab-based studies that utilized psychophysical approaches conducted in an acoustic chamber. Chapter 1 addressed the frequency-dependent sound localization abilities at azimuth of three pinniped species (the harbor seal, Phoca vitulina, the California sea lion, Zalophus californianus, and the northern elephant seal, Mirounga angustirostris). While performances of the sea lion and harbor seal were consistent with the duplex theory of sound localization, the elephant seal, a low-frequency hearing specialist, showed a decreased ability to localize the highest frequencies tested. In Chapter 2 spatial release from masking (SRM), which occurs when a signal and masker are spatially separated resulting in improvement in signal detectability relative to conditions in which they are co-located, was determined in a harbor seal and sea lion. Absolute and masked thresholds were measured at three frequencies and azimuths to determine the detection advantages afforded by this type of spatial auditory processing. Results showed that hearing sensitivity was enhanced by up to 19 and 12 dB in the harbor seal and sea lion, respectively, when the signal and masker were spatially separated. Chapter 3 was a field-based study that quantified both sender and receiver variables of the directional properties of male northern elephant seal calls produce within communication system that serves to delineate dominance status. This included measuring call directivity patterns, observing male-male vocally-mediated interactions, and an acoustic playback study

  3. Effects of Rotatory Low-Frequency Mastoid Vibrations on Auditory Function in Normal Volunteers%低频旋转乳突振动对正常志愿者听力的影响

    Institute of Scientific and Technical Information of China (English)

    彭日顺子; 郑贵亮; 张青; 郑宏良; 邹静

    2015-01-01

    Objective To evaluate the safety of a newly designed rotatory low-frequency mastoid vibration system with respect to the auditory system. Methods Twelve normal volunteers without vertigo were enrolled in the study, including 10 males and 2 females, aged from 23 to 25 years. The vibrator was placed on the right mastoid process with assistance of a special holder. The vibration lasted for 30 minutes. Pure-tone audiometry was performed on both sides before and at 30 minutes, 1 week, and 1 year after exposure to the rotatory low-frequency vibrations. Thresholds at different frequencies at various times post-vibration exposure were compared to the thresholds before exposure using the Wilcoxon signed rank test. Results At 30 minutes after vibration exposure, there was a significant improvement in bone conduction hearing threshold at 0.25, 0.5 and 1 kHz (3, 5 and 3 dB threshold decrease respectively) in ears that had been exposed to the vibration (p<0.05). At 7 days after vibra⁃tion exposure, a significant decrease in the air-conduction threshold in the contralateral ear at 0.25 kHz and 0.5 kHz was record⁃ed (p<0.05). At 1 year after exposure, there were controversial changes in the exposed ear, showing a 6 dB decrease at 0.25 and 0.5 kHz (p<0.05) and a 10 dB increase at 8 kHz (p<0.01) in air conduction threshold, but a increase at 0.25, 0.5 and 1 kHz in bone-conduction threshold (8, 3 or 4 dB respectively) (p<0.01 or 0.05, Wilcoxon test). There appeared to be air conduction hear⁃ing loss at 4 and 8 kHz (7 and 10 dB threshold increase respectively) and bone conduction loss at 0.25 through 4 kHz (7, 6, 6, 8 and 8 dB threshold increase at each tested frequency respectively) in the contralateral ear. Conclusion There is no clear pattern in the small hearing threshold change shortly after exposure to rotatory low frequency mastoid vibration. The changes seen at 1 year after exposure are not consistent with typical vibration-induced hearing threshold change. Therefore

  4. Efficient in vivo electroporation of the postnatal rodent forebrain.

    Directory of Open Access Journals (Sweden)

    Camille Boutin

    Full Text Available Functional gene analysis in vivo represents still a major challenge in biomedical research. Here we present a new method for the efficient introduction of nucleic acids into the postnatal mouse forebrain. We show that intraventricular injection of DNA followed by electroporation induces strong expression of transgenes in radial glia, neuronal precursors and neurons of the olfactory system. We present two proof-of-principle experiments to validate our approach. First, we show that expression of a human isoform of the neural cell adhesion molecule (hNCAM-140 in radial glia cells induces their differentiation into cells showing a neural precursor phenotype. Second, we demonstrate that p21 acts as a cell cycle inhibitor for postnatal neural stem cells. This approach will represent an important tool for future studies of postnatal neurogenesis and of neural development in general.

  5. Song competition affects monoamine levels in sensory and motor forebrain regions of male Lincoln's sparrows (Melospiza lincolnii.

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    Kendra B Sewall

    Full Text Available Male animals often change their behavior in response to the level of competition for mates. Male Lincoln's sparrows (Melospiza lincolnii modulate their competitive singing over the period of a week as a function of the level of challenge associated with competitors' songs. Differences in song challenge and associated shifts in competitive state should be accompanied by neural changes, potentially in regions that regulate perception and song production. The monoamines mediate neural plasticity in response to environmental cues to achieve shifts in behavioral state. Therefore, using high pressure liquid chromatography with electrochemical detection, we compared levels of monoamines and their metabolites from male Lincoln's sparrows exposed to songs categorized as more or less challenging. We compared levels of norepinephrine and its principal metabolite in two perceptual regions of the auditory telencephalon, the caudomedial nidopallium and the caudomedial mesopallium (CMM, because this chemical is implicated in modulating auditory sensitivity to song. We also measured the levels of dopamine and its principal metabolite in two song control nuclei, area X and the robust nucleus of the arcopallium (RA, because dopamine is implicated in regulating song output. We measured the levels of serotonin and its principal metabolite in all four brain regions because this monoamine is implicated in perception and behavioral output and is found throughout the avian forebrain. After controlling for recent singing, we found that males exposed to more challenging song had higher levels of norepinephrine metabolite in the CMM and lower levels of serotonin in the RA. Collectively, these findings are consistent with norepinephrine in perceptual brain regions and serotonin in song control regions contributing to neuroplasticity that underlies socially-induced changes in behavioral state.

  6. Overriding auditory attentional capture.

    Science.gov (United States)

    Dalton, Polly; Lavie, Nilli

    2007-02-01

    Attentional capture by color singletons during shape search can be eliminated when the target is not a feature singleton (Bacon & Egeth, 1994). This suggests that a "singleton detection" search strategy must be adopted for attentional capture to occur. Here we find similar effects on auditory attentional capture. Irrelevant high-intensity singletons interfered with an auditory search task when the target itself was also a feature singleton. However, singleton interference was eliminated when the target was not a singleton (i.e., when nontargets were made heterogeneous, or when more than one target sound was presented). These results suggest that auditory attentional capture depends on the observer's attentional set, as does visual attentional capture. The suggestion that hearing might act as an early warning system that would always be tuned to unexpected unique stimuli must therefore be modified to accommodate these strategy-dependent capture effects. PMID:17557587

  7. 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...

  8. Continuity of visual and auditory rhythms influences sensorimotor coordination.

    Directory of Open Access Journals (Sweden)

    Manuel Varlet

    Full Text Available People often coordinate their movement with visual and auditory environmental rhythms. Previous research showed better performances when coordinating with auditory compared to visual stimuli, and with bimodal compared to unimodal stimuli. However, these results have been demonstrated with discrete rhythms and it is possible that such effects depend on the continuity of the stimulus rhythms (i.e., whether they are discrete or continuous. The aim of the current study was to investigate the influence of the continuity of visual and auditory rhythms on sensorimotor coordination. We examined the dynamics of synchronized oscillations of a wrist pendulum with auditory and visual rhythms at different frequencies, which were either unimodal or bimodal and discrete or continuous. Specifically, the stimuli used were a light flash, a fading light, a short tone and a frequency-modulated tone. The results demonstrate that the continuity of the stimulus rhythms strongly influences visual and auditory motor coordination. Participants' movement led continuous stimuli and followed discrete stimuli. Asymmetries between the half-cycles of the movement in term of duration and nonlinearity of the trajectory occurred with slower discrete rhythms. Furthermore, the results show that the differences of performance between visual and auditory modalities depend on the continuity of the stimulus rhythms as indicated by movements closer to the instructed coordination for the auditory modality when coordinating with discrete stimuli. The results also indicate that visual and auditory rhythms are integrated together in order to better coordinate irrespective of their continuity, as indicated by less variable coordination closer to the instructed pattern. Generally, the findings have important implications for understanding how we coordinate our movements with visual and auditory environmental rhythms in everyday life.

  9. Resizing Auditory Communities

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2012-01-01

    Heard through the ears of the Canadian composer and music teacher R. Murray Schafer the ideal auditory community had the shape of a village. Schafer’s work with the World Soundscape Project in the 70s represent an attempt to interpret contemporary environments through musical and auditory...... of sound as an active component in shaping urban environments. As urban conditions spreads globally, new scales, shapes and forms of communities appear and call for new distinctions and models in the study and representation of sonic environments. Particularly so, since urban environments...

  10. Low Power Adder Based Auditory Filter Architecture

    OpenAIRE

    2014-01-01

    Cochlea devices are powered up with the help of batteries and they should possess long working life to avoid replacing of devices at regular interval of years. Hence the devices with low power consumptions are required. In cochlea devices there are numerous filters, each responsible for frequency variant signals, which helps in identifying speech signals of different audible range. In this paper, multiplierless lookup table (LUT) based auditory filter is implemented. Power aware adder archite...

  11. Spatial processing in the auditory cortex of the macaque monkey

    Science.gov (United States)

    Recanzone, Gregg H.

    2000-10-01

    The patterns of cortico-cortical and cortico-thalamic connections of auditory cortical areas in the rhesus monkey have led to the hypothesis that acoustic information is processed in series and in parallel in the primate auditory cortex. Recent physiological experiments in the behaving monkey indicate that the response properties of neurons in different cortical areas are both functionally distinct from each other, which is indicative of parallel processing, and functionally similar to each other, which is indicative of serial processing. Thus, auditory cortical processing may be similar to the serial and parallel "what" and "where" processing by the primate visual cortex. If "where" information is serially processed in the primate auditory cortex, neurons in cortical areas along this pathway should have progressively better spatial tuning properties. This prediction is supported by recent experiments that have shown that neurons in the caudomedial field have better spatial tuning properties than neurons in the primary auditory cortex. Neurons in the caudomedial field are also better than primary auditory cortex neurons at predicting the sound localization ability across different stimulus frequencies and bandwidths in both azimuth and elevation. These data support the hypothesis that the primate auditory cortex processes acoustic information in a serial and parallel manner and suggest that this may be a general cortical mechanism for sensory perception.

  12. Dissociation of Detection and Discrimination of Pure Tones following Bilateral Lesions of Auditory Cortex

    OpenAIRE

    Andrew R Dykstra; Christine K Koh; Braida, Louis D.; Tramo, Mark Jude

    2012-01-01

    It is well known that damage to the peripheral auditory system causes deficits in tone detection as well as pitch and loudness perception across a wide range of frequencies. However, the extent to which to which the auditory cortex plays a critical role in these basic aspects of spectral processing, especially with regard to speech, music, and environmental sound perception, remains unclear. Recent experiments indicate that primary auditory cortex is necessary for the normally-high perceptual...

  13. The efficacy of the Berard Auditory Integration Training method for learners with attention difficulties / Hannelie Kemp

    OpenAIRE

    Kemp, Johanna Jacoba

    2010-01-01

    Research on the Berard Auditory Integration Training method has shown improvement in the regulation of attention, activity and impulsivity of children whose auditory system have been re-trained. Anecdotal reports have found improvements in sleeping patterns, balance, allergies, eyesight, eating patterns, depression and other seemingly unrelated physiological states. During the Auditory Integration Training (AIT) procedure dynamic music, with a wide range of frequencies, is processed through a...

  14. Regulatory interactions of stress and reward on rat forebrain opioidergic and GABAergic circuitry

    OpenAIRE

    Christiansen, A.M.; HERMAN, J. P.; Ulrich-Lai, Y.M.

    2011-01-01

    Palatable food intake reduces stress responses, suggesting that individuals may consume such “comfort” food as self-medication for stress relief. The mechanism by which palatable foods provide stress relief is not known, but likely lies at the intersection of forebrain reward and stress regulatory circuits. Forebrain opioidergic and gamma-aminobutyric acid (GABA)ergic signaling is critical for both reward and stress regulation suggesting that these systems are prime candidates for mediating s...

  15. Forebrain glucocorticoid receptor gene deletion attenuates behavioral changes and antidepressant responsiveness during chronic stress

    OpenAIRE

    Jacobson, Lauren

    2014-01-01

    Stress is an important risk factor for mood disorders. Stress also stimulates the secretion of glucocorticoids, which have been found to influence mood. To determine the role of forebrain glucocorticoid receptors (GR) in behavioral responses to chronic stress, the present experiments compared behavioral effects of repeated social defeat in mice with forebrain GR deletion and in floxed GR littermate controls. Repeated defeat produced alterations in forced swim and tail suspension immobility in...

  16. Reduced Forebrain Serotonin Transmission is Causally Involved in the Development of Compulsive Cocaine Seeking in Rats

    OpenAIRE

    Pelloux, Yann; Dilleen, Ruth; Economidou, Daina; Theobald, David; Everitt, Barry J.

    2012-01-01

    Whereas the majority of cocaine users quit as they experience the negative consequences of drug use, some lose control over their drug taking and compulsively seek drugs. We report that 20% of rats compulsively seek cocaine despite intermittent negative outcomes after escalating their cocaine self-administration. This compulsive subgroup showed marked reductions in forebrain serotonin utilization; increasing serotonin transmission reduced their compulsive cocaine seeking. Depleting forebrain ...

  17. From pluripotency to forebrain patterning: an in vitro journey astride embryonic stem cells.

    Science.gov (United States)

    Lupo, Giuseppe; Bertacchi, Michele; Carucci, Nicoletta; Augusti-Tocco, Gabriella; Biagioni, Stefano; Cremisi, Federico

    2014-08-01

    Embryonic stem cells (ESCs) have been used extensively as in vitro models of neural development and disease, with special efforts towards their conversion into forebrain progenitors and neurons. The forebrain is the most complex brain region, giving rise to several fundamental structures, such as the cerebral cortex, the hypothalamus, and the retina. Due to the multiplicity of signaling pathways playing different roles at distinct times of embryonic development, the specification and patterning of forebrain has been difficult to study in vivo. Research performed on ESCs in vitro has provided a large body of evidence to complement work in model organisms, but these studies have often been focused more on cell type production than on cell fate regulation. In this review, we systematically reassess the current literature in the field of forebrain development in mouse and human ESCs with a focus on the molecular mechanisms of early cell fate decisions, taking into consideration the specific culture conditions, exogenous and endogenous molecular cues as described in the original studies. The resulting model of early forebrain induction and patterning provides a useful framework for further studies aimed at reconstructing forebrain development in vitro for basic research or therapy. PMID:24643740

  18. Lesions of the basal forebrain cholinergic system in mice disrupt idiothetic navigation.

    Directory of Open Access Journals (Sweden)

    Adam S Hamlin

    Full Text Available Loss of integrity of the basal forebrain cholinergic neurons is a consistent feature of Alzheimer's disease, and measurement of basal forebrain degeneration by magnetic resonance imaging is emerging as a sensitive diagnostic marker for prodromal disease. It is also known that Alzheimer's disease patients perform poorly on both real space and computerized cued (allothetic or uncued (idiothetic recall navigation tasks. Although the hippocampus is required for allothetic navigation, lesions of this region only mildly affect idiothetic navigation. Here we tested the hypothesis that the cholinergic medial septo-hippocampal circuit is important for idiothetic navigation. Basal forebrain cholinergic neurons were selectively lesioned in mice using the toxin saporin conjugated to a basal forebrain cholinergic neuronal marker, the p75 neurotrophin receptor. Control animals were able to learn and remember spatial information when tested on a modified version of the passive place avoidance test where all extramaze cues were removed, and animals had to rely on idiothetic signals. However, the exploratory behaviour of mice with cholinergic basal forebrain lesions was highly disorganized during this test. By contrast, the lesioned animals performed no differently from controls in tasks involving contextual fear conditioning and spatial working memory (Y maze, and displayed no deficits in potentially confounding behaviours such as motor performance, anxiety, or disturbed sleep/wake cycles. These data suggest that the basal forebrain cholinergic system plays a specific role in idiothetic navigation, a modality that is impaired early in Alzheimer's disease.

  19. Neuronal activities of forebrain structures with respect to bladder contraction in cats.

    Science.gov (United States)

    Yamamoto, Tatsuya; Sakakibara, Ryuji; Nakazawa, Ken; Uchiyama, Tomoyuki; Shimizu, Eiji; Hattori, Takamichi; Kuwabara, Satoshi

    2010-03-31

    The forebrain is one of the important suprapontine micturition centres. Previous studies have shown that electrical stimulation of the frontal lobe and the anterior cingulate gyrus elicited either inhibition or facilitation of bladder contraction. Patients with frontal lobe tumours and aneurysms showed micturition disorders. Functional brain imaging studies showed that several parts of the forebrain are activated during bladder filling. We aimed to examine neuronal activities of forebrain structures with respect to bladder contraction in cats. In 14 adult male cats under ketamine anaesthesia in which a spontaneous isovolumetric bladder-contraction/relaxation cycle had been generated, we carried out extracellular single-unit recording in forebrain with respect to the contraction/relaxation cycles in the bladder. We recorded 112 neurons that were related to the bladder-contraction/relaxation cycles. Ninety-four neurons were found to be tonically activated during the bladder-relaxation phase, whereas the remaining 18 neurons were tonically activated during the bladder-contraction phase. Both types of neuron were widely distributed around the cruciate sulcus. Most were located medially (medial and superior frontal gyrus) and the rest were located laterally (middle and inferior frontal gyrus). Neurons recorded in forebrain structures were activated with respect to the contraction/relaxation cycles in the bladder. Forebrain structures may have a significant role in regulating bladder contraction in cats. PMID:20153810

  20. Idealized computational models for auditory receptive fields.

    Directory of Open Access Journals (Sweden)

    Tony Lindeberg

    Full Text Available We present a theory by which idealized models of auditory receptive fields can be derived in a principled axiomatic manner, from a set of structural properties to (i enable invariance of receptive field responses under natural sound transformations and (ii ensure internal consistency between spectro-temporal receptive fields at different temporal and spectral scales. For defining a time-frequency transformation of a purely temporal sound signal, it is shown that the framework allows for a new way of deriving the Gabor and Gammatone filters as well as a novel family of generalized Gammatone filters, with additional degrees of freedom to obtain different trade-offs between the spectral selectivity and the temporal delay of time-causal temporal window functions. When applied to the definition of a second-layer of receptive fields from a spectrogram, it is shown that the framework leads to two canonical families of spectro-temporal receptive fields, in terms of spectro-temporal derivatives of either spectro-temporal Gaussian kernels for non-causal time or a cascade of time-causal first-order integrators over the temporal domain and a Gaussian filter over the logspectral domain. For each filter family, the spectro-temporal receptive fields can be either separable over the time-frequency domain or be adapted to local glissando transformations that represent variations in logarithmic frequencies over time. Within each domain of either non-causal or time-causal time, these receptive field families are derived by uniqueness from the assumptions. It is demonstrated how the presented framework allows for computation of basic auditory features for audio processing and that it leads to predictions about auditory receptive fields with good qualitative similarity to biological receptive fields measured in the inferior colliculus (ICC and primary auditory cortex (A1 of mammals.

  1. Enhanced representation of spectral contrasts in the primary auditory cortex

    Directory of Open Access Journals (Sweden)

    Nicolas eCatz

    2013-06-01

    Full Text Available The role of early auditory processing may be to extract some elementary features from an acoustic mixture in order to organize the auditory scene. To accomplish this task, the central auditory system may rely on the fact that sensory objects are often composed of spectral edges, i.e. regions where the stimulus energy changes abruptly over frequency. The processing of acoustic stimuli may benefit from a mechanism enhancing the internal representation of spectral edges. While the visual system is thought to rely heavily on this mechanism (enhancing spatial edges, it is still unclear whether a related process plays a significant role in audition. We investigated the cortical representation of spectral edges, using acoustic stimuli composed of multi-tone pips whose time-averaged spectral envelope contained suppressed or enhanced regions. Importantly, the stimuli were designed such that neural responses properties could be assessed as a function of stimulus frequency during stimulus presentation. Our results suggest that the representation of acoustic spectral edges is enhanced in the auditory cortex, and that this enhancement is sensitive to the characteristics of the spectral contrast profile, such as depth, sharpness and width. Spectral edges are maximally enhanced for sharp contrast and large depth. Cortical activity was also suppressed at frequencies within the suppressed region. To note, the suppression of firing was larger at frequencies nearby the lower edge of the suppressed region than at the upper edge. Overall, the present study gives critical insights into the processing of spectral contrasts in the auditory system.

  2. An auditory-periphery model of the effects of acoustic trauma on auditory nerve responses

    Science.gov (United States)

    Bruce, Ian C.; Sachs, Murray B.; Young, Eric D.

    2003-01-01

    Acoustic trauma degrades the auditory nerve's tonotopic representation of acoustic stimuli. Recent physiological studies have quantified the degradation in responses to the vowel eh and have investigated amplification schemes designed to restore a more correct tonotopic representation than is achieved with conventional hearing aids. However, it is difficult from the data to quantify how much different aspects of the cochlear pathology contribute to the impaired responses. Furthermore, extensive experimental testing of potential hearing aids is infeasible. Here, both of these concerns are addressed by developing models of the normal and impaired auditory peripheries that are tested against a wide range of physiological data. The effects of both outer and inner hair cell status on model predictions of the vowel data were investigated. The modeling results indicate that impairment of both outer and inner hair cells contribute to degradation in the tonotopic representation of the formant frequencies in the auditory nerve. Additionally, the model is able to predict the effects of frequency-shaping amplification on auditory nerve responses, indicating the model's potential suitability for more rapid development and testing of hearing aid schemes.

  3. Cochlear Responses and Auditory Brainstem Response Functions in Adults with Auditory Neuropathy/ Dys-Synchrony and Individuals with Normal Hearing

    Directory of Open Access Journals (Sweden)

    Zahra Jafari

    2007-06-01

    Full Text Available Background and Aim: Physiologic measures of cochlear and auditory nerve function may be of assis¬tance in distinguishing between hearing disorders due primarily to auditory nerve impairment from those due primarily to cochlear hair cells dysfunction. The goal of present study was to measure of co-chlear responses (otoacoustic emissions and cochlear microphonics and auditory brainstem response in some adults with auditory neuropathy/ dys-synchrony and subjects with normal hearing. Materials and Methods: Patients were 16 adults (32 ears in age range of 14-30 years with auditory neu¬ropathy/ dys-synchrony and 16 individuals in age range of 16-30 years from both sexes. The results of transient otoacoustic emissions, cochlear microphonics and auditory brainstem response measures were compared in both groups and the effects of age, sex, ear and degree of hearing loss were studied. Results: The pure-tone average was 48.1 dB HL in auditory neuropathy/dys-synchrony group and the fre¬quency of low tone loss and flat audiograms were higher among other audiogram's shapes. Transient oto¬acoustic emissions were shown in all auditory neuropathy/dys-synchrony people except two cases and its average was near in both studied groups. The latency and amplitude of the biggest reversed co-chlear microphonics response were higher in auditory neuropathy/dys-synchrony patients than control peo¬ple significantly. The correlation between cochlear microphonics amplitude and degree of hearing loss was not significant, and age had significant effect in some cochlear microphonics measures. Audi-tory brainstem response had no response in auditory neuropathy/dys-synchrony patients even with low stim¬uli rates. Conclusion: In adults with speech understanding worsen than predicted from the degree of hearing loss that suspect to auditory neuropathy/ dys-synchrony, the frequency of low tone loss and flat audiograms are higher. Usually auditory brainstem response is absent in

  4. 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.

  5. Dopamine receptor gene expression by enkephalin neurons in rat forebrain

    International Nuclear Information System (INIS)

    In situ hybridization experiments were performed with brain sections from normal, control and haloperidol-treated rats to identify and map the cells expressing the D2 dopamine receptor gene. D2 receptor mRNA was detected with radioactive or biotinylated oligonucleotide probes. D2 receptor mRNA was present in glandular cells of the pituitary intermediate lobe and in neurons of the substantia nigra, ventral tegmental area, and forebrain, especially in caudate putamen, nucleus accumbens, olfactory tubercle, and piriform cortex. Hybridization with D2 and preproenkephalin A probes in adjacent sections, as well as combined hybridization with the two probes in the same sections, demonstrated that all detectable enkephalin neurons in the striatum contained the D2 receptor mRNA. Large neurons in caudate putamen, which were unlabeled with the preproenkephalin A probe and which may have been cholinergic, also expressed the D2 receptor gene. Haloperidol treatment (14 or 21 days) provoked an increase in mRNA content for D2 receptor and preproenkephalin A in the striatum. This suggests that the increase in D2 receptor number observed after haloperidol treatment is due to increased activity of the D2 gene. These results indicate that in the striatum, the enkephalin neurons are direct targets for dopamine liberated from mesostriatal neurons

  6. Molecular Diversity Subdivides the Adult Forebrain Neural Stem Cell Population

    Science.gov (United States)

    Giachino, Claudio; Basak, Onur; Lugert, Sebastian; Knuckles, Philip; Obernier, Kirsten; Fiorelli, Roberto; Frank, Stephan; Raineteau, Olivier; Alvarez–Buylla, Arturo; Taylor, Verdon

    2014-01-01

    Neural stem cells (NSCs) in the ventricular domain of the subventricular zone (V-SVZ) of rodents produce neurons throughout life while those in humans become largely inactive or may be lost during infancy. Most adult NSCs are quiescent, express glial markers, and depend on Notch signaling for their self-renewal and the generation of neurons. Using genetic markers and lineage tracing, we identified subpopulations of adult V-SVZ NSCs (type 1, 2, and 3) indicating a striking heterogeneity including activated, brain lipid binding protein (BLBP, FABP7) expressing stem cells. BLBP+ NSCs are mitotically active components of pinwheel structures in the lateral ventricle walls and persistently generate neurons in adulthood. BLBP+ NSCs express epidermal growth factor (EGF) receptor, proliferate in response to EGF, and are a major clonogenic population in the SVZ. We also find BLBP expressed by proliferative ventricular and sub-ventricular progenitors in the fetal and postnatal human brain. Loss of BLBP+ stem/progenitor cells correlates with reduced neurogenesis in aging rodents and postnatal humans. These findings of molecular heterogeneity and proliferative differences subdivide the NSC population and have implications for neurogenesis in the forebrain of mammals during aging. PMID:23964022

  7. BALDEY: A database of auditory lexical decisions.

    Science.gov (United States)

    Ernestus, Mirjam; Cutler, Anne

    2015-01-01

    In an auditory lexical decision experiment, 5541 spoken content words and pseudowords were presented to 20 native speakers of Dutch. The words vary in phonological make-up and in number of syllables and stress pattern, and are further representative of the native Dutch vocabulary in that most are morphologically complex, comprising two stems or one stem plus derivational and inflectional suffixes, with inflections representing both regular and irregular paradigms; the pseudowords were matched in these respects to the real words. The BALDEY ("biggest auditory lexical decision experiment yet") data file includes response times and accuracy rates, with for each item morphological information plus phonological and acoustic information derived from automatic phonemic segmentation of the stimuli. Two initial analyses illustrate how this data set can be used. First, we discuss several measures of the point at which a word has no further neighbours and compare the degree to which each measure predicts our lexical decision response outcomes. Second, we investigate how well four different measures of frequency of occurrence (from written corpora, spoken corpora, subtitles, and frequency ratings by 75 participants) predict the same outcomes. These analyses motivate general conclusions about the auditory lexical decision task. The (publicly available) BALDEY database lends itself to many further analyses. PMID:25397865

  8. Central auditory masking by an illusory tone.

    Directory of Open Access Journals (Sweden)

    Christopher J Plack

    Full Text Available Many natural sounds fluctuate over time. The detectability of sounds in a sequence can be reduced by prior stimulation in a process known as forward masking. Forward masking is thought to reflect neural adaptation or neural persistence in the auditory nervous system, but it has been unclear where in the auditory pathway this processing occurs. To address this issue, the present study used a "Huggins pitch" stimulus, the perceptual effects of which depend on central auditory processing. Huggins pitch is an illusory tonal sensation produced when the same noise is presented to the two ears except for a narrow frequency band that is different (decorrelated between the ears. The pitch sensation depends on the combination of the inputs to the two ears, a process that first occurs at the level of the superior olivary complex in the brainstem. Here it is shown that a Huggins pitch stimulus produces more forward masking in the frequency region of the decorrelation than a noise stimulus identical to the Huggins-pitch stimulus except with perfect correlation between the ears. This stimulus has a peripheral neural representation that is identical to that of the Huggins-pitch stimulus. The results show that processing in, or central to, the superior olivary complex can contribute to forward masking in human listeners.

  9. Auditory Learning. Dimensions in Early Learning Series.

    Science.gov (United States)

    Zigmond, Naomi K.; Cicci, Regina

    The monograph discusses the psycho-physiological operations for processing of auditory information, the structure and function of the ear, the development of auditory processes from fetal responses through discrimination, language comprehension, auditory memory, and auditory processes related to written language. Disorders of auditory learning…

  10. Visual–auditory spatial processing in auditory cortical neurons

    OpenAIRE

    Bizley, Jennifer K.; King, Andrew J

    2008-01-01

    Neurons responsive to visual stimulation have now been described in the auditory cortex of various species, but their functions are largely unknown. Here we investigate the auditory and visual spatial sensitivity of neurons recorded in 5 different primary and non-primary auditory cortical areas of the ferret. We quantified the spatial tuning of neurons by measuring the responses to stimuli presented across a range of azimuthal positions and calculating the mutual information (MI) between the ...

  11. Probucol Attenuates Oxidative Stress, Energy Starvation, and Nitric Acid Production Following Transient Forebrain Ischemia in the Rat Hippocampus

    OpenAIRE

    Abdulhakeem A. Al-Majed

    2011-01-01

    Oxidative stress and energy depletion are believed to participate in hippocampal neuronal damage after forebrain ischemia. This study has been initiated to investigate the potential neuroprotective effects of probucol, a lipid-lowering drug with strong antioxidant properties, against transient forebrain ischemia-induced neuronal damage and biochemical abnormalities in rat hippocampal CA1 region. Adult male Wistar albino rats were subjected to forebrain ischemia and injected with probucol for ...

  12. Anatomy and Physiology of the Auditory Tracts

    Directory of Open Access Journals (Sweden)

    Mohammad hosein Hekmat Ara

    1999-03-01

    Full Text Available Hearing is one of the excel sense of human being. Sound waves travel through the medium of air and enter the ear canal and then hit the tympanic membrane. Middle ear transfer almost 60-80% of this mechanical energy to the inner ear by means of “impedance matching”. Then, the sound energy changes to traveling wave and is transferred based on its specific frequency and stimulates organ of corti. Receptors in this organ and their synapses transform mechanical waves to the neural waves and transfer them to the brain. The central nervous system tract of conducting the auditory signals in the auditory cortex will be explained here briefly.

  13. The auditory characteristics of children with inner auditory canal stenosis.

    Science.gov (United States)

    Ai, Yu; Xu, Lei; Li, Li; Li, Jianfeng; Luo, Jianfen; Wang, Mingming; Fan, Zhaomin; Wang, Haibo

    2016-07-01

    Conclusions This study shows that the prevalence of auditory neuropathy spectrum disorder (ANSD) in the children with inner auditory canal (IAC) stenosis is much higher than those without IAC stenosis, regardless of whether they have other inner ear anomalies. In addition, the auditory characteristics of ANSD with IAC stenosis are significantly different from those of ANSD without any middle and inner ear malformations. Objectives To describe the auditory characteristics in children with IAC stenosis as well as to examine whether the narrow inner auditory canal is associated with ANSD. Method A total of 21 children, with inner auditory canal stenosis, participated in this study. A series of auditory tests were measured. Meanwhile, a comparative study was conducted on the auditory characteristics of ANSD, based on whether the children were associated with isolated IAC stenosis. Results Wave V in the ABR was not observed in all the patients, while cochlear microphonic (CM) response was detected in 81.1% ears with stenotic IAC. Sixteen of 19 (84.2%) ears with isolated IAC stenosis had CM response present on auditory brainstem responses (ABR) waveforms. There was no significant difference in ANSD characteristics between the children with and without isolated IAC stenosis. PMID:26981851

  14. Sexually dimorphic effects of the Lhx7 null mutation on forebrain cholinergic function.

    Science.gov (United States)

    Fragkouli, A; Stamatakis, A; Zographos, E; Pachnis, V; Stylianopoulou, F

    2006-01-01

    It has been reported recently that mice lacking both alleles of the LIM-homeobox gene Lhx7, display dramatically reduced number of forebrain cholinergic neurons. In the present study, we investigated whether the Lhx7 mutation affects male and female mice differently, given the fact that gender differences are consistently observed in forebrain cholinergic function. Our results show that in adult male as well as female Lhx7 homozygous mutants there is a dramatic loss of choline acetyltransferase immunoreactive forebrain neurons, both projection and interneurons. The reduction of forebrain choline acetyltransferase immunoreactive neurons in Lhx7 homozygous mutants is accompanied by a decrease of acetylcholinesterase histochemical staining in all forebrain cholinergic neuron target areas of both male and female homozygous mutants. Furthermore, there was an increase of M1-, but not M2-, muscarinic acetylcholine receptor binding site density in the somatosensory cortex and basal ganglia of only the female homozygous mutant mice. Such an increase can be regarded as a mechanism acting to compensate for the dramatically reduced cholinergic input, raising the possibility that the forebrain cholinergic system in female mice may be more plastic and responsive to situations of limited neurotransmitter availability. Finally, our study provides additional data for the sexual dimorphism of the forebrain cholinergic system, as female mice appear to have a lower density of M1-muscarinic acetylcholine receptors in the striatal areas of the basal ganglia and a higher density of M2-muscarinic acetylcholine receptors, in a number of cortical areas, as well as the striatal areas of the basal ganglia. PMID:16338089

  15. The role of auditory feedback in sustaining vocal vibrato

    Science.gov (United States)

    Leydon, Ciara; Bauer, Jay J.; Larson, Charles R.

    2003-09-01

    Vocal vibrato and tremor are characterized by oscillations in voice fundamental frequency (F0). These oscillations may be sustained by a control loop within the auditory system. One component of the control loop is the pitch-shift reflex (PSR). The PSR is a closed loop negative feedback reflex that is triggered in response to discrepancies between intended and perceived pitch with a latency of ~100 ms. Consecutive compensatory reflexive responses lead to oscillations in pitch every ~200 ms, resulting in ~5-Hz modulation of F0. Pitch-shift reflexes were elicited experimentally in six subjects while they sustained /you/ vowels at a comfortable pitch and loudness. Auditory feedback was sinusoidally modulated at discrete integer frequencies (1 to 10 Hz) with +/-25 cents amplitude. Modulated auditory feedback induced oscillations in voice F0 output of all subjects at rates consistent with vocal vibrato and tremor. Transfer functions revealed peak gains at 4 to 7 Hz in all subjects, with an average peak gain at 5 Hz. These gains occurred in the modulation frequency region where the voice output and auditory feedback signals were in phase. A control loop in the auditory system may sustain vocal vibrato and tremorlike oscillations in voice F0.

  16. 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.

  17. Assessment of auditory processing in children with dyslalia

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    Wlodarczyk £.

    2011-09-01

    Full Text Available The objective of the work was to assess occurrence of central auditory processing disorders in children with dyslalia. Material and method. The material included 30 children at the age 798 years old being under long-term speech therapy care due to articulation disorders. All the children were subjected to the phoniatric and speech examination, including tonal and impedance audiometry, speech therapist's consultation and psychologist's consultation. Electrophysi-ological (N2, P2, N2, P2, P300 record and following psychoacoustic test of central auditory functions were performed (Frequency Pattern Test. Results. Analysis of the results revealed disorders in the process of sound analysis within frequency and P300 wave latency prolongation in children with dyslalia. Conclusions. Auditory processing disorders may be significant in development of correct articulation in children, they also may explain unsatisfactory results of long-term speech therapy

  18. Adaptive auditory feedback control of the production of formant trajectories in the Mandarin triphthong ∕iau∕ and its pattern of generalization

    OpenAIRE

    Cai, Shanqing; Ghosh, Satrajit S.; Frank H Guenther; Perkell, Joseph S.

    2010-01-01

    In order to test whether auditory feedback is involved in the planning of complex articulatory gestures in time-varying phonemes, the current study examined native Mandarin speakers' responses to auditory perturbations of their auditory feedback of the trajectory of the first formant frequency during their production of the triphthong ∕iau∕. On average, subjects adaptively adjusted their productions to partially compensate for the perturbations in auditory feedback. This result indicates that...

  19. Auditory and non-auditory effects of noise on health

    NARCIS (Netherlands)

    Basner, M.; Babisch, W.; Davis, A.; Brink, M.; Clark, C.; Janssen, S.A.; Stansfeld, S.

    2013-01-01

    Noise is pervasive in everyday life and can cause both auditory and non-auditory health eff ects. Noise-induced hearing loss remains highly prevalent in occupational settings, and is increasingly caused by social noise exposure (eg, through personal music players). Our understanding of molecular mec

  20. The impact of educational level on performance on auditory processing tests

    Directory of Open Access Journals (Sweden)

    Cristina F.B. Murphy

    2016-03-01

    Full Text Available Research has demonstrated that a higher level of education is associated with better performance on cognitive tests among middle-aged and elderly people. However, the effects of education on auditory processing skills have not yet been evaluated. Previous demonstrations of sensory-cognitive interactions in the aging process indicate the potential importance of this topic. Therefore, the primary purpose of this study was to investigate the performance of middle-aged and elderly people with different levels of formal education on auditory processing tests. A total of 177 adults with no evidence of cognitive, psychological or neurological conditions took part in the research. The participants completed a series of auditory assessments, including dichotic digit, frequency pattern and speech-in-noise tests. A working memory test was also performed to investigate the extent to which auditory processing and cognitive performance were associated. The results demonstrated positive but weak correlations between years of schooling and performance on all of the tests applied. The factor years of schooling was also one of the best predictors of frequency pattern and speech-in-noise test performance. Additionally, performance on the working memory, frequency pattern and dichotic digit tests was also correlated, suggesting that the influence of educational level on auditory processing performance might be associated with the cognitive demand of the auditory processing tests rather than auditory sensory aspects itself. Longitudinal research is required to investigate the causal relationship between educational level and auditory processing skills.

  1. Hypermnesia using auditory input.

    Science.gov (United States)

    Allen, J

    1992-07-01

    The author investigated whether hypermnesia would occur with auditory input. In addition, the author examined the effects of subjects' knowledge that they would later be asked to recall the stimuli. Two groups of 26 subjects each were given three successive recall trials after they listened to an audiotape of 59 high-imagery nouns. The subjects in the uninformed group were not told that they would later be asked to remember the words; those in the informed group were. Hypermnesia was evident, but only in the uninformed group. PMID:1447564

  2. Which People with Specific Language Impairment have Auditory Processing Deficits?

    Science.gov (United States)

    McArthur, G M; Bishop, D V M

    2004-02-01

    An influential theory attributes developmental disorders of language and literacy to low-level auditory perceptual difficulties. However, evidence to date has been inconsistent and contradictory. We investigated whether this mixed picture could be explained in terms of heterogeneity in the language-impaired population. In Experiment 1, the behavioural responses of 16 people with specific language impairment (SLI) and 16 control listeners (aged 10 to 19 years) to auditory backward recognition masking (ABRM) stimuli and unmasked tones indicated that a subgroup of people with SLI are less able to discriminate between the frequencies of sounds regardless of their rate of presentation. Further, these people tended to be the younger participants, and were characterised by relatively poor nonword reading. In Experiment 2, the auditory event-related potentials (ERPs) of the same groups to unmasked tones were measured. Listeners with SLI tended to have age-inappropriate waveforms in the N1-P2-N2 region, regardless of their auditory discrimination scores in Experiment 1. Together, these results suggest that SLI may be characterised by immature development of auditory cortex, such that adult-level frequency discrimination performance is attained several years later than normal. PMID:21038192

  3. 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.

  4. The Perception of Auditory Motion.

    Science.gov (United States)

    Carlile, Simon; Leung, Johahn

    2016-01-01

    The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception. PMID:27094029

  5. Lexical and Sublexical Feedback in Auditory Word Recognition.

    Science.gov (United States)

    Pitt, Mark A.; Samuel, Arthur G.

    1995-01-01

    Results from 3 experiments in auditory word recognition involving a total of 266 undergraduates supported interactive models of lexical processing, but required additional sublexical processes. The hypothesized sublexical mechanism is fast acting and frequency sensitive and produces top-down effects, but its operation has not yet been fully…

  6. Auditory Spectral Integration in the Perception of Static Vowels

    Science.gov (United States)

    Fox, Robert Allen; Jacewicz, Ewa; Chang, Chiung-Yun

    2011-01-01

    Purpose: To evaluate potential contributions of broadband spectral integration in the perception of static vowels. Specifically, can the auditory system infer formant frequency information from changes in the intensity weighting across harmonics when the formant itself is missing? Does this type of integration produce the same results in the lower…

  7. Auditory Long Latency Responses to Tonal and Speech Stimuli

    Science.gov (United States)

    Swink, Shannon; Stuart, Andrew

    2012-01-01

    Purpose: The effects of type of stimuli (i.e., nonspeech vs. speech), speech (i.e., natural vs. synthetic), gender of speaker and listener, speaker (i.e., self vs. other), and frequency alteration in self-produced speech on the late auditory cortical evoked potential were examined. Method: Young adult men (n = 15) and women (n = 15), all with…

  8. Modifying Directionality through Auditory System Scaling in a Robotic Lizard

    DEFF Research Database (Denmark)

    Shaikh, Danish; Hallam, John; Christensen-Dalsgaard, Jakob

    2010-01-01

    The peripheral auditory system of a lizard is strongly directional. This directionality is created by acoustical coupling of the two eardrums and is strongly dependent on characteristics of the middle ear, such as interaural distance, resonance frequency of the middle ear cavity and of the tympanum...

  9. The Auditory Skills Necessary for Echolocation: A New Explanation.

    Science.gov (United States)

    Carlson-Smith, C.; Wiener, W. R.

    1996-01-01

    This study employed an audiometric test battery with nine blindfolded undergraduate students to explore success factors in echolocation. Echolocation performance correlated significantly with several specific auditory measures. No relationship was found between high-frequency sensitivity and echolocation performance. (Author/PB)

  10. Cholinergic modulation of auditory steady-state response in the auditory cortex of the freely moving rat.

    Science.gov (United States)

    Zhang, J; Ma, L; Li, W; Yang, P; Qin, L

    2016-06-01

    As disturbance in auditory steady-state response (ASSR) has been consistently found in many neuropsychiatric disorders, such as autism spectrum disorder and schizophrenia, there is considerable interest in the development of translational rat models to elucidate the underlying neural and neurochemical mechanisms involved in ASSR. This is the first study to investigate the effects of the non-selective muscarinic antagonist scopolamine and the cholinesterase inhibitor donepezil (also in combination with scopolamine) on ASSR. We recorded the local field potentials through the chronic microelectrodes implanted in the auditory cortex of freely moving rat. ASSRs were recorded in response to auditory stimuli delivered over a range of frequencies (10-80Hz) and averaged over 60 trials. We found that a single dose of scopolamine produced a temporal attenuation in response to auditory stimuli; the most attenuation occurred at 40Hz. Time-frequency analysis revealed deficits in both power and phase-locking to 40Hz. Donepezil augmented 40-Hz steady-state power and phase-locking. Scopolamine combined with donepezil had an enhanced effect on the phase-locking, but not power of ASSR. These changes induced by cholinergic drugs suggest an involvement of muscarinic neurotransmission in auditory processing and provide a rodent model investigating the neurochemical mechanism of neurophysiological deficits seen in patients. PMID:26964684

  11. 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...

  12. Cortical oscillations in auditory perception and speech: evidence for two temporal windows in human auditory cortex

    Directory of Open Access Journals (Sweden)

    Huan eLuo

    2012-05-01

    Full Text Available Natural sounds, including vocal communication sounds, contain critical information at multiple time scales. Two essential temporal modulation rates in speech have been argued to be in the low gamma band (~20-80 ms duration information and the theta band (~150-300 ms, corresponding to segmental and syllabic modulation rates, respectively. On one hypothesis, auditory cortex implements temporal integration using time constants closely related to these values. The neural correlates of a proposed dual temporal window mechanism in human auditory cortex remain poorly understood. We recorded MEG responses from participants listening to non-speech auditory stimuli with different temporal structures, created by concatenating frequency-modulated segments of varied segment durations. We show that these non-speech stimuli with temporal structure matching speech-relevant scales (~25 ms and ~200 ms elicit reliable phase tracking in the corresponding associated oscillatory frequencies (low gamma and theta bands. In contrast, stimuli with non-matching temporal structure do not. Furthermore, the topography of theta band phase tracking shows rightward lateralization while gamma band phase tracking occurs bilaterally. The results support the hypothesis that there exists multi-time resolution processing in cortex on discontinuous scales and provide evidence for an asymmetric organization of temporal analysis (asymmetrical sampling in time, AST. The data argue for a macroscopic-level neural mechanism underlying multi-time resolution processing: the sliding and resetting of intrinsic temporal windows on privileged time scales.

  13. Musical experience, auditory perception and reading-related skills in children.

    Directory of Open Access Journals (Sweden)

    Karen Banai

    Full Text Available BACKGROUND: The relationships between auditory processing and reading-related skills remain poorly understood despite intensive research. Here we focus on the potential role of musical experience as a confounding factor. Specifically we ask whether the pattern of correlations between auditory and reading related skills differ between children with different amounts of musical experience. METHODOLOGY/PRINCIPAL FINDINGS: Third grade children with various degrees of musical experience were tested on a battery of auditory processing and reading related tasks. Very poor auditory thresholds and poor memory skills were abundant only among children with no musical education. In this population, indices of auditory processing (frequency and interval discrimination thresholds were significantly correlated with and accounted for up to 13% of the variance in reading related skills. Among children with more than one year of musical training, auditory processing indices were better, yet reading related skills were not correlated with them. A potential interpretation for the reduction in the correlations might be that auditory and reading-related skills improve at different rates as a function of musical training. CONCLUSIONS/SIGNIFICANCE: Participants' previous musical training, which is typically ignored in studies assessing the relations between auditory and reading related skills, should be considered. Very poor auditory and memory skills are rare among children with even a short period of musical training, suggesting musical training could have an impact on both. The lack of correlation in the musically trained population suggests that a short period of musical training does not enhance reading related skills of individuals with within-normal auditory processing skills. Further studies are required to determine whether the associations between musical training, auditory processing and memory are indeed causal or whether children with poor auditory and

  14. Auditory distance perception in humans: a review of cues, development, neuronal bases, and effects of sensory loss.

    Science.gov (United States)

    Kolarik, Andrew J; Moore, Brian C J; Zahorik, Pavel; Cirstea, Silvia; Pardhan, Shahina

    2016-02-01

    Auditory distance perception plays a major role in spatial awareness, enabling location of objects and avoidance of obstacles in the environment. However, it remains under-researched relative to studies of the directional aspect of sound localization. This review focuses on the following four aspects of auditory distance perception: cue processing, development, consequences of visual and auditory loss, and neurological bases. The several auditory distance cues vary in their effective ranges in peripersonal and extrapersonal space. The primary cues are sound level, reverberation, and frequency. Nonperceptual factors, including the importance of the auditory event to the listener, also can affect perceived distance. Basic internal representations of auditory distance emerge at approximately 6 months of age in humans. Although visual information plays an important role in calibrating auditory space, sensorimotor contingencies can be used for calibration when vision is unavailable. Blind individuals often manifest supranormal abilities to judge relative distance but show a deficit in absolute distance judgments. Following hearing loss, the use of auditory level as a distance cue remains robust, while the reverberation cue becomes less effective. Previous studies have not found evidence that hearing-aid processing affects perceived auditory distance. Studies investigating the brain areas involved in processing different acoustic distance cues are described. Finally, suggestions are given for further research on auditory distance perception, including broader investigation of how background noise and multiple sound sources affect perceived auditory distance for those with sensory loss. PMID:26590050

  15. Music-induced cortical plasticity and lateral inhibition in the human auditory cortex as foundations for tonal tinnitus treatment

    OpenAIRE

    Christo Pantev; Hidehiko Okamoto

    2013-01-01

    Over the past 15 years, we have studied plasticity in the human auditory cortex by means of magnetoencephalography (MEG). Two main topics nurtured our curiosity: the effects of musical training on plasticity in the auditory system, and the effects of lateral inhibition. One of our plasticity studies found that listening to notched music for 3 h inhibited the neuronal activity in the auditory cortex that corresponded to the center-frequency of the notch, suggesting suppression of neural activi...

  16. Emergence of tuning to natural stimulus statistics along the central auditory pathway.

    Directory of Open Access Journals (Sweden)

    Jose A Garcia-Lazaro

    Full Text Available We have previously shown that neurons in primary auditory cortex (A1 of anaesthetized (ketamine/medetomidine ferrets respond more strongly and reliably to dynamic stimuli whose statistics follow "natural" 1/f dynamics than to stimuli exhibiting pitch and amplitude modulations that are faster (1/f(0.5 or slower (1/f(2 than 1/f. To investigate where along the central auditory pathway this 1/f-modulation tuning arises, we have now characterized responses of neurons in the central nucleus of the inferior colliculus (ICC and the ventral division of the mediate geniculate nucleus of the thalamus (MGV to 1/f(γ distributed stimuli with γ varying between 0.5 and 2.8. We found that, while the great majority of neurons recorded from the ICC showed a strong preference for the most rapidly varying (1/f(0.5 distributed stimuli, responses from MGV neurons did not exhibit marked or systematic preferences for any particular γ exponent. Only in A1 did a majority of neurons respond with higher firing rates to stimuli in which γ takes values near 1. These results indicate that 1/f tuning emerges at forebrain levels of the ascending auditory pathway.

  17. 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

  18. Auditory perspective taking.

    Science.gov (United States)

    Martinson, Eric; Brock, Derek

    2013-06-01

    Effective communication with a mobile robot using speech is a difficult problem even when you can control the auditory scene. Robot self-noise or ego noise, echoes and reverberation, and human interference are all common sources of decreased intelligibility. Moreover, in real-world settings, these problems are routinely aggravated by a variety of sources of background noise. Military scenarios can be punctuated by high decibel noise from materiel and weaponry that would easily overwhelm a robot's normal speaking volume. Moreover, in nonmilitary settings, fans, computers, alarms, and transportation noise can cause enough interference to make a traditional speech interface unusable. This work presents and evaluates a prototype robotic interface that uses perspective taking to estimate the effectiveness of its own speech presentation and takes steps to improve intelligibility for human listeners. PMID:23096077

  19. Tactile feedback improves auditory spatial localization

    OpenAIRE

    Gori, Monica; Vercillo, Tiziana; Sandini, Giulio; Burr, David

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds b...

  20. Tactile feedback improves auditory spatial localization

    OpenAIRE

    Monica eGori; Tiziana eVercillo; Giulio eSandini; David eBurr

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial-bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds b...

  1. Regulation of a remote Sonic hedgehog forebrain enhancer by the Six3 homeoprotein

    Science.gov (United States)

    Jeong, Yongsu; Leskow, Federico Coluccio; El-Jaick, Kenia; Roessler, Erich; Muenke, Maximilian; Yocum, Anastasia; Dubourg, Christele; Li, Xue; Geng, Xin; Oliver, Guillermo; Epstein, Douglas J.

    2009-01-01

    The secreted morphogen, Sonic hedgehog (Shh) is a significant determinant of brain size and craniofacial morphology1–4. In humans, SHH haploinsufficiency results in holoprosencephaly (HPE)5, a defect in anterior midline formation. Despite the importance of maintaining SHH transcript levels above a critical threshold, we know little about the upstream regulators of SHH expression in the forebrain. Here we describe a combination of genetic and biochemical experiments to uncover a critical pair of cis and trans acting determinants of Shh forebrain expression. A rare nucleotide variant located 460kb upstream of SHH was discovered in an individual with HPE that resulted in the loss of Shh brain enhancer-2 (SBE2) activity in the hypothalamus of transgenic mouse embryos. Using a DNA affinity capture assay we screened SBE2 sequence for DNA binding proteins and identified members of the Six3/Six6 homeodomain family as candidate regulators of Shh transcription. Six3 and Six6 showed reduced binding affinity for the mutant compared to wild type SBE2 sequence. Moreover, HPE causing mutations in Six3 failed to bind and activate SBE2, whereas, Shh forebrain expression was unaltered in Six6−/− embryos. These data provide a direct link between Six3 and Shh regulation during normal forebrain development and in the pathogenesis of HPE. PMID:18836447

  2. Chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain.

    Directory of Open Access Journals (Sweden)

    Gerard Honig

    Full Text Available BACKGROUND: Serotonin (5-HT is a neurotransmitter with important roles in the regulation of neurobehavioral processes, particularly those regulating affect in humans. Drugs that potentiate serotonergic neurotransmission by selectively inhibiting the reuptake of serotonin (SSRIs are widely used for the treatment of psychiatric disorders. Although the regulation of serotonin synthesis may be an factor in SSRI efficacy, the effect of chronic SSRI administration on 5-HT synthesis is not well understood. Here, we describe effects of chronic administration of the SSRI citalopram (CIT on 5-HT synthesis and content in the mouse forebrain. METHODOLOGY/PRINCIPAL FINDINGS: Citalopram was administered continuously to adult male C57BL/6J mice via osmotic minipump for 2 days, 14 days or 28 days. Plasma citalopram levels were found to be within the clinical range. 5-HT synthesis was assessed using the decarboxylase inhibition method. Citalopram administration caused a suppression of 5-HT synthesis at all time points. CIT treatment also caused a reduction in forebrain 5-HIAA content. Following chronic CIT treatment, forebrain 5-HT stores were more sensitive to the depleting effects of acute decarboxylase inhibition. CONCLUSIONS/SIGNIFICANCE: Taken together, these results demonstrate that chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain. Furthermore, our results indicate that chronic 5-HT reuptake inhibition renders 5-HT brain stores more sensitive to alterations in serotonin synthesis. These results suggest that the regulation of 5-HT synthesis warrants consideration in efforts to develop novel antidepressant strategies.

  3. Effects of heavy ions on rabbit tissues: damage to the forebrain

    International Nuclear Information System (INIS)

    As part of a study of progressive radiation effects in normal tissues, the forebrains of New Zealand white rabbits (Oryctolagus cuniculus) (about 6 weeks old) were irradiated locally with single acute doses of 60Co γ-photons (LETsub(infinity)=0.3 keV/μm), Ne ions (LETsub(infinity)=35+-3 keV/μm) or Ar ions (LETsub(infinity)=90+-5 keV/μm). Other rabbits received fractionated doses of 60Co γ-photons according to a standard radiotherapeutic protocol. Irradiated rabbits and appropriately aged controls were sacrificed at selected intervals, and whole sagittal sections of their brains were examined for pathological changes. Forebrain damage was scored with subjective indices based on histological differences between the anterior (irradiated) and posterior (unirradiated) regions of the brain. Those indices ranged from zero (no apparent damage) to five (severe infarctions, etc.). At intermediate levels of forebrain damage, the relative biological effectiveness (r.b.e.) of each heavy ion was similar to that found for alopecia and cataractogenesis, and the early expression of the damage was also accelerated as the LETsub(infinity) increased. Late deterioration of the forebrain appeared also to be accelerated by increasing LETsub(infinity), although its accurate quantification was not possible because other priorities in the overall experimental design limited systematic sacrifice of the animals. (author)

  4. Effects of heavy ions on rabbit tissues: damage to the forebrain

    Energy Technology Data Exchange (ETDEWEB)

    Cox, A.B.; Keng, P.C.; Lee, A.C.; Lett, J.T. (Colorado State Univ., Fort Collins (USA). Dept. of Radiology and Radiation Biology)

    1982-10-01

    As part of a study of progressive radiation effects in normal tissues, the forebrains of New Zealand white rabbits (Oryctolagus cuniculus) (about 6 weeks old) were irradiated locally with single acute doses of /sup 60/Co ..gamma..-photons (LETsub(infinity)=0.3 keV/..mu..m), Ne ions (LETsub(infinity)=35+-3 keV/..mu..m) or Ar ions (LETsub(infinity)=90+-5 keV/..mu..m). Other rabbits received fractionated doses of /sup 60/Co ..gamma..-photons according to a standard radiotherapeutic protocol. Irradiated rabbits and appropriately aged controls were sacrificed at selected intervals, and whole sagittal sections of their brains were examined for pathological changes. Forebrain damage was scored with subjective indices based on histological differences between the anterior (irradiated) and posterior (unirradiated) regions of the brain. Those indices ranged from zero (no apparent damage) to five (severe infarctions, etc.). At intermediate levels of forebrain damage, the relative biological effectiveness (r.b.e.) of each heavy ion was similar to that found for alopecia and cataractogenesis, and the early expression of the damage was also accelerated as the LETsub(infinity) increased. Late deterioration of the forebrain appeared also to be accelerated by increasing LETsub(infinity), although its accurate quantification was not possible because other priorities in the overall experimental design limited systematic sacrifice of the animals.

  5. 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. PMID:26541581

  6. Auditory and non-auditory effects of noise on health

    OpenAIRE

    Basner, Mathias; Babisch, Wolfgang; Davis, Adrian; Brink, Mark; Clark, Charlotte; Janssen, Sabine; Stansfeld, Stephen

    2013-01-01

    Noise is pervasive in everyday life and can cause both auditory and non-auditory health effects. Noise-induced hearing loss remains highly prevalent in occupational settings, and is increasingly caused by social noise exposure (eg, through personal music players). Our understanding of molecular mechanisms involved in noise-induced hair-cell and nerve damage has substantially increased, and preventive and therapeutic drugs will probably become available within 10 years. Evidence of the non-aud...

  7. Listener orientation and spatial judgments of elevated auditory percepts

    Science.gov (United States)

    Parks, Anthony J.

    How do listener head rotations affect auditory perception of elevation? This investi-. gation addresses this in the hopes that perceptual judgments of elevated auditory. percepts may be more thoroughly understood in terms of dynamic listening cues. engendered by listener head rotations and that this phenomenon can be psychophys-. ically and computationally modeled. Two listening tests were conducted and a. psychophysical model was constructed to this end. The frst listening test prompted. listeners to detect an elevated auditory event produced by a virtual noise source. orbiting the median plane via 24-channel ambisonic spatialization. Head rotations. were tracked using computer vision algorithms facilitated by camera tracking. The. data were used to construct a dichotomous criteria model using factorial binary. logistic regression model. The second auditory test investigated the validity of the. historically supported frequency dependence of auditory elevation perception using. narrow-band noise for continuous and brief stimuli with fxed and free-head rotation. conditions. The data were used to construct a multinomial logistic regression model. to predict categorical judgments of above, below, and behind. Finally, in light. of the psychophysical data found from the above studies, a functional model of. elevation perception for point sources along the cone of confusion was constructed. using physiologically-inspired signal processing methods along with top-down pro-. cessing utilizing principles of memory and orientation. The model is evaluated using. white noise bursts for 42 subjects' head-related transfer functions. The investigation. concludes with study limitations, possible implications, and speculation on future. research trajectories.

  8. Modeling of Auditory Neuron Response Thresholds with Cochlear Implants

    Directory of Open Access Journals (Sweden)

    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.

  9. Spatial organization of tettigoniid auditory receptors: insights from neuronal tracing.

    Science.gov (United States)

    Strauß, Johannes; Lehmann, Gerlind U C; Lehmann, Arne W; Lakes-Harlan, Reinhard

    2012-11-01

    The auditory sense organ of Tettigoniidae (Insecta, Orthoptera) is located in the foreleg tibia and consists of scolopidial sensilla which form a row termed crista acustica. The crista acustica is associated with the tympana and the auditory trachea. This ear is a highly ordered, tonotopic sensory system. As the neuroanatomy of the crista acustica has been documented for several species, the most distal somata and dendrites of receptor neurons have occasionally been described as forming an alternating or double row. We investigate the spatial arrangement of receptor cell bodies and dendrites by retrograde tracing with cobalt chloride solution. In six tettigoniid species studied, distal receptor neurons are consistently arranged in double-rows of somata rather than a linear sequence. This arrangement of neurons is shown to affect 30-50% of the overall auditory receptors. No strict correlation of somata positions between the anterio-posterior and dorso-ventral axis was evident within the distal crista acustica. Dendrites of distal receptors occasionally also occur in a double row or are even massed without clear order. Thus, a substantial part of auditory receptors can deviate from a strictly straight organization into a more complex morphology. The linear organization of dendrites is not a morphological criterion that allows hearing organs to be distinguished from nonhearing sense organs serially homologous to ears in all species. Both the crowded arrangement of receptor somata and dendrites may result from functional constraints relating to frequency discrimination, or from developmental constraints of auditory morphogenesis in postembryonic development. PMID:22807283

  10. Modeling of Auditory Neuron Response Thresholds with Cochlear Implants.

    Science.gov (United States)

    Venail, Frederic; Mura, Thibault; Akkari, Mohamed; Mathiolon, Caroline; Menjot de Champfleur, Sophie; Piron, Jean Pierre; Sicard, Marielle; Sterkers-Artieres, Françoise; Mondain, Michel; Uziel, Alain

    2015-01-01

    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 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. PMID:26236725

  11. Probucol attenuates oxidative stress, energy starvation, and nitric acid production following transient forebrain ischemia in the rat hippocampus.

    Science.gov (United States)

    Al-Majed, Abdulhakeem A

    2011-01-01

    Oxidative stress and energy depletion are believed to participate in hippocampal neuronal damage after forebrain ischemia. This study has been initiated to investigate the potential neuroprotective effects of probucol, a lipid-lowering drug with strong antioxidant properties, against transient forebrain ischemia-induced neuronal damage and biochemical abnormalities in rat hippocampal CA1 region. Adult male Wistar albino rats were subjected to forebrain ischemia and injected with probucol for the next 7 successive days, and compared to controls. Forebrain ischemia resulted in a significant decrease in the number of intact neurons (77%), glutathione (GSH), and adenosine triphosphate (ATP), and a significant increase in thiobarbituric acid reactive substances (TBARS) and total nitrate/nitrite, (NO(x)) production in hippocampal tissues. The administration of probucol attenuated forebrain ischemia-induced neuronal damage, manifested as a complete reversal of the decrease in the number of intact neurons, ATP and GSH and the increase in TBARS and NO(x) in hippocampal tissues. This study demonstrates that probucol treatment abates forebrain ischemia-induced hippocampal neuronal loss, energy depletion, and oxidative stress in hippocampal CA1 region. Thus, probucol could be a promising neuroprotective agent in the treatment of forebrain ischemia. PMID:21904644

  12. Dopamine receptor activation modulates GABA neuron migration from the basal forebrain to the cerebral cortex.

    Science.gov (United States)

    Crandall, James E; McCarthy, Deirdre M; Araki, Kiyomi Y; Sims, John R; Ren, Jia-Qian; Bhide, Pradeep G

    2007-04-01

    GABA neurons of the cerebral cortex and other telencephalic structures are produced in the basal forebrain and migrate to their final destinations during the embryonic period. The embryonic basal forebrain is enriched in dopamine and its receptors, creating a favorable environment for dopamine to influence GABA neuron migration. However, whether dopamine receptor activation can influence GABA neuron migration is not known. We show that dopamine D1 receptor activation promotes and D2 receptor activation decreases GABA neuron migration from the medial and caudal ganglionic eminences to the cerebral cortex in slice preparations of embryonic mouse forebrain. Slice preparations from D1 or D2 receptor knock-out mouse embryos confirm the findings. In addition, D1 receptor electroporation into cells of the basal forebrain and pharmacological activation of the receptor promote migration of the electroporated cells to the cerebral cortex. Analysis of GABA neuron numbers in the cerebral wall of the dopamine receptor knock-out mouse embryos further confirmed the effects of dopamine receptor activation on GABA neuron migration. Finally, dopamine receptor activation mobilizes striatal neuronal cytoskeleton in a manner consistent with the effects on neuronal migration. These data show that impairing the physiological balance between D1 and D2 receptors can alter GABA neuron migration from the basal forebrain to the cerebral cortex. The intimate relationship between dopamine and GABA neuron development revealed here may offer novel insights into developmental disorders such as schizophrenia, attention deficit or autism, and fetal cocaine exposure, all of which are associated with dopamine and GABA imbalance. PMID:17409246

  13. Auditory Processing Disorder in Children

    Science.gov (United States)

    ... free publications Find organizations Related Topics Auditory Neuropathy Autism Spectrum Disorder: Communication Problems in Children Dysphagia Quick ... NIH… Turning Discovery Into Health ® National Institute on Deafness and Other Communication Disorders 31 Center Drive, MSC ...

  14. Auditory Processing Disorder (For Parents)

    Science.gov (United States)

    ... and school. A positive, realistic attitude and healthy self-esteem in a child with APD can work wonders. And kids with APD can go on to ... Parents MORE ON THIS TOPIC Auditory Processing Disorder Special ...

  15. Behavioral estimates of human frequency selectivity at low frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado

    low sound frequencies. As a consequence of our lack of knowledge, we cannot accurately model our perception of complex low-frequency sound (such as that emitted by wind turbines or industrial processes, which can easily produce annoyance) nor make meaningful predictions of our perception based on...... physical sound measurements. In this PhD thesis a detailed description of frequency selectivity at low frequencies is given. Different experiments have been performed to determine the properties of human auditory filters. Besides, loudness perception of low-frequency sinusoidal signals has been evaluated....... In the analysis of results, factors that may influence our perception of low-frequency sound have been considered. It was found that the relative sharpness of auditory filters is poor at low frequencies. However, their bandwidth decreases with decreasing frequency down to about 80 Hz. Below this, a...

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

    Science.gov (United States)

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

    2013-01-01

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

  17. Receptive field plasticity of neurons in rat auditory cortex

    Institute of Scientific and Technical Information of China (English)

    YANG Wenwei; GAO Lixia; SUN Xinde

    2004-01-01

    Using conventional electrophysiological technique, we investigated the plasticity of the frequency receptive fields (RF) of auditory cortex (AC) neurons in rats. In the AC, when the frequency difference between conditioning stimulus frequency (CSF) and the best frequency (BF) was in the range of 1-4 kHz, the frequency RF of AC neurons shifted. The smaller the differences between CSF and BF, the higher the probability of the RF shift and the greater the degree of the RF shift. To some extent, the plasticity of RF was dependent on the duration of the session of conditioning stimulus (CS). When the frequency difference between CSF and BF was bigger, the duration of the CS session needed to induce the plasticity was longer. The recovery time course of the frequency RF showed opposite changes after CS cessation.The RF shift could be induced by the frequency that was either higher or lower than the control BF, demonstrating no clear directional preference. The frequency RF of some neurons showed bidirectional shift, and the RF of other neurons showed single directional shift. The results suggest that the frequency RF plasticity of AC neurons could be considered as an ideal model for studying plasticity mechanism. The present study also provides important evidence for further study of learning and memory in auditory system.

  18. You can't stop the music: reduced auditory alpha power and coupling between auditory and memory regions facilitate the illusory perception of music during noise.

    Science.gov (United States)

    Müller, Nadia; Keil, Julian; Obleser, Jonas; Schulz, Hannah; Grunwald, Thomas; Bernays, René-Ludwig; Huppertz, Hans-Jürgen; Weisz, Nathan

    2013-10-01

    Our brain has the capacity of providing an experience of hearing even in the absence of auditory stimulation. This can be seen as illusory conscious perception. While increasing evidence postulates that conscious perception requires specific brain states that systematically relate to specific patterns of oscillatory activity, the relationship between auditory illusions and oscillatory activity remains mostly unexplained. To investigate this we recorded brain activity with magnetoencephalography and collected intracranial data from epilepsy patients while participants listened to familiar as well as unknown music that was partly replaced by sections of pink noise. We hypothesized that participants have a stronger experience of hearing music throughout noise when the noise sections are embedded in familiar compared to unfamiliar music. This was supported by the behavioral results showing that participants rated the perception of music during noise as stronger when noise was presented in a familiar context. Time-frequency data show that the illusory perception of music is associated with a decrease in auditory alpha power pointing to increased auditory cortex excitability. Furthermore, the right auditory cortex is concurrently synchronized with the medial temporal lobe, putatively mediating memory aspects associated with the music illusion. We thus assume that neuronal activity in the highly excitable auditory cortex is shaped through extensive communication between the auditory cortex and the medial temporal lobe, thereby generating the illusion of hearing music during noise. PMID:23664946

  19. Psychology of auditory perception.

    Science.gov (United States)

    Lotto, Andrew; Holt, Lori

    2011-09-01

    Audition is often treated as a 'secondary' sensory system behind vision in the study of cognitive science. In this review, we focus on three seemingly simple perceptual tasks to demonstrate the complexity of perceptual-cognitive processing involved in everyday audition. After providing a short overview of the characteristics of sound and their neural encoding, we present a description of the perceptual task of segregating multiple sound events that are mixed together in the signal reaching the ears. Then, we discuss the ability to localize the sound source in the environment. Finally, we provide some data and theory on how listeners categorize complex sounds, such as speech. In particular, we present research on how listeners weigh multiple acoustic cues in making a categorization decision. One conclusion of this review is that it is time for auditory cognitive science to be developed to match what has been done in vision in order for us to better understand how humans communicate with speech and music. WIREs Cogni Sci 2011 2 479-489 DOI: 10.1002/wcs.123 For further resources related to this article, please visit the WIREs website. PMID:26302301

  20. The role of auditory abilities in basic mechanisms of cognition in older adults

    Directory of Open Access Journals (Sweden)

    Massimo eGrassi

    2013-10-01

    Full Text Available The aim of this study was to assess age-related differences between young and older adults in auditory abilities and to investigate the relationship between auditory abilities and basic mechanisms of cognition in older adults. Although there is a certain consensus that the participant’s sensitivity to the absolute intensity of sounds (such as that measured via pure tone audiometry explains his/her cognitive performance, there is not yet much evidence that the participant’s auditory ability (i.e., the whole supra-threshold processing of sounds explains his/her cognitive performance. Twenty-eight young adults (age < 35, 26 young-old adults (65 ≤ age ≤75 and 28 old-old adults (age > 75 were presented with a set of tasks estimating several auditory abilities (i.e., frequency discrimination, intensity discrimination, duration discrimination, timbre discrimination, gap detection, amplitude modulation detection, and the absolute threshold for a 1 kHz pure tone and the participant’s working memory, cognitive inhibition, and processing speed. Results showed an age-related decline in both auditory and cognitive performance. Moreover, regression analyses showed that a subset of the auditory abilities (i.e., the ability to discriminate frequency, duration, timbre, and the ability to detect amplitude modulation explained a significant part of the variance observed in processing speed in older adults. Overall, the present results highlight the relationship between auditory abilities and basic mechanisms of cognition.

  1. Vibrotactile activation of the auditory cortices in deaf versus hearing adults.

    Science.gov (United States)

    Auer, Edward T; Bernstein, Lynne E; Sungkarat, Witaya; Singh, Manbir

    2007-05-01

    Neuroplastic changes in auditory cortex as a result of lifelong perceptual experience were investigated. Adults with early-onset deafness and long-term hearing aid experience were hypothesized to have undergone auditory cortex plasticity due to somatosensory stimulation. Vibrations were presented on the hand of deaf and normal-hearing participants during functional MRI. Vibration stimuli were derived from speech or were a fixed frequency. Higher, more widespread activity was observed within auditory cortical regions of the deaf participants for both stimulus types. Life-long somatosensory stimulation due to hearing aid use could explain the greater activity observed with deaf participants. PMID:17426591

  2. He hears, she hears: are there sex differences in auditory processing?

    Science.gov (United States)

    Yoder, Kathleen M; Phan, Mimi L; Lu, Kai; Vicario, David S

    2015-03-01

    Songbirds learn individually unique songs through vocal imitation and use them in courtship and territorial displays. Previous work has identified a forebrain auditory area, the caudomedial nidopallium (NCM), that appears specialized for discriminating and remembering conspecific vocalizations. In zebra finches (ZFs), only males produce learned vocalizations, but both sexes process these and other signals. This study assessed sex differences in auditory processing by recording extracellular multiunit activity at multiple sites within NCM. Juvenile female ZFs (n = 46) were reared in individual isolation and artificially tutored with song. In adulthood, songs were played back to assess auditory responses, stimulus-specific adaptation, neural bias for conspecific song, and memory for the tutor's song, as well as recently heard songs. In a subset of females (n = 36), estradiol (E2) levels were manipulated to test the contribution of E2, known to be synthesized in the brain, to auditory responses. Untreated females (n = 10) showed significant differences in response magnitude and stimulus-specific adaptation compared to males reared in the same paradigm (n = 9). In hormone-manipulated females, E2 augmentation facilitated the memory for recently heard songs in adulthood, but neither E2 augmentation (n = 15) nor E2 synthesis blockade (n = 9) affected tutor song memory or the neural bias for conspecific song. The results demonstrate subtle sex differences in processing communication signals, and show that E2 levels in female songbirds can affect the memory for songs of potential suitors, thus contributing to the process of mate selection. The results also have potential relevance to clinical interventions that manipulate E2 in human patients. PMID:25220950

  3. Brain Barriers and a Subpopulation of Astroglial Progenitors of Developing Human Forebrain Are Immunostained for the Glycoprotein YKL-40

    DEFF Research Database (Denmark)

    Bjørnbak, Camilla; Brøchner, Christian B; Larsen, Lars A;

    2014-01-01

    YKL-40, a glycoprotein involved in cell differentiation, has been associated with neurodevelopmental disorders, angiogenesis, neuroinflammation and glioblastomas. We evaluated YKL-40 protein distribution in the early human forebrain using double-labeling immunofluorescence and immunohistochemistr...

  4. Auditory and non-auditory effects of noise on health.

    Science.gov (United States)

    Basner, Mathias; Babisch, Wolfgang; Davis, Adrian; Brink, Mark; Clark, Charlotte; Janssen, Sabine; Stansfeld, Stephen

    2014-04-12

    Noise is pervasive in everyday life and can cause both auditory and non-auditory health effects. Noise-induced hearing loss remains highly prevalent in occupational settings, and is increasingly caused by social noise exposure (eg, through personal music players). Our understanding of molecular mechanisms involved in noise-induced hair-cell and nerve damage has substantially increased, and preventive and therapeutic drugs will probably become available within 10 years. Evidence of the non-auditory effects of environmental noise exposure on public health is growing. Observational and experimental studies have shown that noise exposure leads to annoyance, disturbs sleep and causes daytime sleepiness, affects patient outcomes and staff performance in hospitals, increases the occurrence of hypertension and cardiovascular disease, and impairs cognitive performance in schoolchildren. In this Review, we stress the importance of adequate noise prevention and mitigation strategies for public health. PMID:24183105

  5. Synaptic enrichment of microRNAs in adult mouse forebrain is related to structural features of their precursors

    OpenAIRE

    Smalheiser Neil R

    2008-01-01

    Abstract Within mouse forebrain, a subset of microRNAs are significantly enriched in synaptoneurosomes (a synaptic fraction containing pinched-off dendritic spines) and a subset are significantly depleted relative to total forebrain homogenate. Here I show that, as a group, the pre-miR hairpin precursors of synaptically enriched microRNAs exhibit significantly different structural features than those that are non-enriched or depleted. Precursors of synaptically enriched microRNAs tend to hav...

  6. Basal Forebrain Cholinergic Deficits Reduce Glucose Metabolism and Function of Cholinergic and GABAergic Systems in the Cingulate Cortex

    OpenAIRE

    Jeong, Da Un; Oh, Jin Hwan; Lee, Ji Eun; Lee, Jihyeon; Cho, Zang Hee; Chang, Jin Woo; Chang, Won Seok

    2015-01-01

    Purpose Reduced brain glucose metabolism and basal forebrain cholinergic neuron degeneration are common features of Alzheimer's disease and have been correlated with memory function. Although regions representing glucose hypometabolism in patients with Alzheimer's disease are targets of cholinergic basal forebrain neurons, the interaction between cholinergic denervation and glucose hypometabolism is still unclear. The aim of the present study was to evaluate glucose metabolism changes caused ...

  7. Individual differences in auditory abilities.

    Science.gov (United States)

    Kidd, Gary R; Watson, Charles S; Gygi, Brian

    2007-07-01

    Performance on 19 auditory discrimination and identification tasks was measured for 340 listeners with normal hearing. Test stimuli included single tones, sequences of tones, amplitude-modulated and rippled noise, temporal gaps, speech, and environmental sounds. Principal components analysis and structural equation modeling of the data support the existence of a general auditory ability and four specific auditory abilities. The specific abilities are (1) loudness and duration (overall energy) discrimination; (2) sensitivity to temporal envelope variation; (3) identification of highly familiar sounds (speech and nonspeech); and (4) discrimination of unfamiliar simple and complex spectral and temporal patterns. Examination of Scholastic Aptitude Test (SAT) scores for a large subset of the population revealed little or no association between general or specific auditory abilities and general intellectual ability. The findings provide a basis for research to further specify the nature of the auditory abilities. Of particular interest are results suggestive of a familiar sound recognition (FSR) ability, apparently specialized for sound recognition on the basis of limited or distorted information. This FSR ability is independent of normal variation in both spectral-temporal acuity and of general intellectual ability. PMID:17614500

  8. Interactions between auditory and somatosensory feedback for voice F0 control

    OpenAIRE

    Larson, Charles R.; Altman, Kenneth W.; Liu, Hanjun; Hain, Timothy C.

    2008-01-01

    Previous studies have demonstrated the importance of both kinesthetic and auditory feedback for control of voice fundamental frequency (F0). In the present study, a possible interaction between auditory feedback and kinesthetic feedback for control of voice F0 was tested by administering local anesthetic to the vocal folds in the presence of perturbations in voice pitch feedback. Responses to pitch-shifted voice feedback were larger when the vocal fold mucosa was anesthetized than during norm...

  9. Neural Representations of Complex Temporal Modulations in the Human Auditory Cortex

    OpenAIRE

    Ding, Nai; Simon, Jonathan Z.

    2009-01-01

    Natural sounds such as speech contain multiple levels and multiple types of temporal modulations. Because of nonlinearities of the auditory system, however, the neural response to multiple, simultaneous temporal modulations cannot be predicted from the neural responses to single modulations. Here we show the cortical neural representation of an auditory stimulus simultaneously frequency modulated (FM) at a high rate, fFM ≈ 40 Hz, and amplitude modulation (AM) at a slow rate, fAM

  10. Connecting the ear to the brain: molecular mechanisms of auditory circuit assembly

    OpenAIRE

    Appler, Jessica M; Goodrich, Lisa V.

    2011-01-01

    Our sense of hearing depends on precisely organized circuits that allow us to sense, perceive, and respond to complex sounds in our environment, from music and language to simple warning signals. Auditory processing begins in the cochlea of the inner ear, where sounds are detected by sensory hair cells and then transmitted to the central nervous system by spiral ganglion neurons, which faithfully preserve the frequency, intensity, and timing of each stimulus. During the assembly of auditory c...

  11. Forebrain-Specific Loss of BMPRII in Mice Reduces Anxiety and Increases Object Exploration.

    Directory of Open Access Journals (Sweden)

    Zofeyah L McBrayer

    Full Text Available To investigate the role of Bone Morphogenic Protein Receptor Type II (BMPRII in learning, memory, and exploratory behavior in mice, a tissue-specific knockout of BMPRII in the post-natal hippocampus and forebrain was generated. We found that BMPRII mutant mice had normal spatial learning and memory in the Morris water maze, but showed significantly reduced swimming speeds with increased floating behavior. Further analysis using the Porsolt Swim Test to investigate behavioral despair did not reveal any differences in immobility between mutants and controls. In the Elevated Plus Maze, BMPRII mutants and Smad4 mutants showed reduced anxiety, while in exploratory tests, BMPRII mutants showed more interest in object exploration. These results suggest that loss of BMPRII in the mouse hippocampus and forebrain does not disrupt spatial learning and memory encoding, but instead impacts exploratory and anxiety-related behaviors.

  12. Different auditory feedback control for echolocation and communication in horseshoe bats.

    Directory of Open Access Journals (Sweden)

    Ying Liu

    Full Text Available Auditory feedback from the animal's own voice is essential during bat echolocation: to optimize signal detection, bats continuously adjust various call parameters in response to changing echo signals. Auditory feedback seems also necessary for controlling many bat communication calls, although it remains unclear how auditory feedback control differs in echolocation and communication. We tackled this question by analyzing echolocation and communication in greater horseshoe bats, whose echolocation pulses are dominated by a constant frequency component that matches the frequency range they hear best. To maintain echoes within this "auditory fovea", horseshoe bats constantly adjust their echolocation call frequency depending on the frequency of the returning echo signal. This Doppler-shift compensation (DSC behavior represents one of the most precise forms of sensory-motor feedback known. We examined the variability of echolocation pulses emitted at rest (resting frequencies, RFs and one type of communication signal which resembles an echolocation pulse but is much shorter (short constant frequency communication calls, SCFs and produced only during social interactions. We found that while RFs varied from day to day, corroborating earlier studies in other constant frequency bats, SCF-frequencies remained unchanged. In addition, RFs overlapped for some bats whereas SCF-frequencies were always distinctly different. This indicates that auditory feedback during echolocation changed with varying RFs but remained constant or may have been absent during emission of SCF calls for communication. This fundamentally different feedback mechanism for echolocation and communication may have enabled these bats to use SCF calls for individual recognition whereas they adjusted RF calls to accommodate the daily shifts of their auditory fovea.

  13. Computational Perspectives on Forebrain Microcircuits Implicated in Reinforcement Learning, Action Selection, and Cognitive Control

    OpenAIRE

    Bullock, Daniel; Tan, Can Ozan; John, Yohan J.

    2009-01-01

    Abundant new information about signaling pathways in forebrain microcircuits presents many challenges, and opportunities for discovery, to computational neuroscientists who strive to bridge from microcircuits to flexible cognition and action. Accurate treatment of microcircuit pathways is especially critical for creating models that correctly predict the outcomes of candidate neurological therapies. Recent models are trying to specify how cortical circuits that enable planning and voluntary a...

  14. Attention, prediction and sequence learning : roles of the cholinergic basal forebrain and the retrosplenial cortex

    OpenAIRE

    Córdova, Christopher Andy

    2005-01-01

    Our ability to foresee and shape biologically important events relies on a combination of visuospatial attention, memory capacities, and an ability to learn new sequences of goal-directed action. A novel set of behavioral studies were conducted to investigate neurobiological processes that underlie selective attention and visuospatial sequence learning. The first experiment assessed a theorized computational role of basal forebrain cholinergic neurons in modulating attention by increasing sti...

  15. Alteration of Forebrain Neurogenesis after Cervical Spinal Cord Injury in the Adult Rat

    OpenAIRE

    ValeryAMatarazzo; PatrickGauthier

    2012-01-01

    Spinal cord injury (SCI) triggers a complex cellular response at the injury site, leading to the formation of a dense scar tissue. Despite this local tissue remodeling, the consequences of SCI at the cellular level in distant rostral sites (i.e. brain), remain unknown. In this study, we asked whether cervical SCI could alter cell dynamics in neurogenic areas of the adult rat forebrain. To this aim, we quantified BrdU incorporation and determined the phenotypes of newly generated cells (neuron...

  16. Intact working memory in the absence of forebrain neuronal glycine transporter 1

    OpenAIRE

    Dubroqua, Sylvain; Serrano, Lucas; Boison, Detlev; FELDON, JORAM; Gargiulo, Pascual A.; Yee, Benjamin K.

    2012-01-01

    Glycine transporter 1 (GlyT1) is a potential pharmacological target to ameliorate memory deficits attributable to N-methyl-d-aspartate receptor (NMDAR) hypofunction. Disruption of glycine-reuptake near excitatory synapses is expected to enhance NMDAR function by increasing glycine-B site occupancy. Genetic models with conditional GlyT1 deletion restricted to forebrain neurons have yielded several promising promnesic effects, yet its impact on working memory function remains essentially unansw...

  17. Frontal forebrain lesions : effects on the foraging and apomorphine pecking of pigeons

    OpenAIRE

    Wynne, Brigitte; Delius, Juan

    1996-01-01

    The role of the nucleus basalis prosencephali (Bas), a frontal forebrain structure peculiar to birds, in the control of forage pecking and apomorphine-induced pecking was investigated. In a quasi-natural grit-grain selection task bilateral coagulations of the Bas and the associated neostriatum frontolaterale (Nfl) caused a marked fall in grain per peck uptake and a simultaneous increase in grit per peck uptake. Bas lesions also has a reducing effect on the compulsive pecking elicited by syste...

  18. Regulation of a remote Sonic hedgehog forebrain enhancer by the Six3 homeoprotein

    OpenAIRE

    Jeong, Yongsu; Leskow, Federico Coluccio; El-Jaick, Kenia; Roessler, Erich; Muenke, Maximilian; Yocum, Anastasia; Dubourg, Christele; Li, Xue; Geng, Xin; Oliver, Guillermo; Epstein, Douglas J.

    2008-01-01

    The secreted morphogen, Sonic hedgehog (Shh) is a significant determinant of brain size and craniofacial morphology1–4. In humans, SHH haploinsufficiency results in holoprosencephaly (HPE)5, a defect in anterior midline formation. Despite the importance of maintaining SHH transcript levels above a critical threshold, we know little about the upstream regulators of SHH expression in the forebrain. Here we describe a combination of genetic and biochemical experiments to uncover a critical pair ...

  19. Activation of the Basal Forebrain by the Orexin/Hypocretin Neurons: Orexin International Symposium

    OpenAIRE

    Arrigoni, Elda; Mochizuki, Takatoshi; Scammell, Thomas E.

    2009-01-01

    The orexin neurons play an essential role in driving arousal and in maintaining normal wakefulness. Lack of orexin neurotransmission produces a chronic state of hypoarousal characterized by excessive sleepiness, frequent transitions between wake and sleep, and episodes of cataplexy. A growing body of research now suggests that the basal forebrain (BF) may be a key site through which the orexin-producing neurons promote arousal. Here we review anatomical, pharmacological and electrophysiologic...

  20. Brain-derived neurotrophic factor signaling is altered in the forebrain of Engrailed-2 knockout mice.

    Science.gov (United States)

    Zunino, G; Messina, A; Sgadò, P; Baj, G; Casarosa, S; Bozzi, Y

    2016-06-01

    Engrailed-2 (En2), a homeodomain transcription factor involved in regionalization and patterning of the midbrain and hindbrain regions has been associated to autism spectrum disorders (ASDs). En2 knockout (En2(-/-)) mice show ASD-like features accompanied by a significant loss of GABAergic subpopulations in the hippocampus and neocortex. Brain-derived neurotrophic factor (BDNF) is a crucial factor for the postnatal development of forebrain GABAergic neurons, and altered GABA signaling has been hypothesized to underlie the symptoms of ASD. Here we sought to determine whether interneuron loss in the En2(-/-) forebrain might be related to altered expression of BDNF and its signaling receptors. We first evaluated the expression of different BDNF mRNA isoforms in the neocortex and hippocampus of wild-type (WT) and En2(-/-) mice. Quantitative RT-PCR showed a marked down-regulation of several splicing variants of BDNF mRNA in the neocortex but not hippocampus of adult En2(-/-) mice, as compared to WT controls. Accordingly, levels of mature BDNF protein were lower in the neocortex but not hippocampus of En2(-/-) mice, as compared to WT. Increased levels of phosphorylated TrkB and decreased levels of p75 receptor were also detected in the neocortex of mutant mice. Accordingly, the expression of low density lipoprotein receptor (LDLR) and RhoA, two genes regulated via p75 was significantly altered in forebrain areas of mutant mice. These data indicate that BDNF signaling alterations might be involved in the anatomical changes observed in the En2(-/-) forebrain and suggest a pathogenic role of altered BDNF signaling in this mouse model of ASD. PMID:26987954

  1. Glucocorticoid receptor overexpression in forebrain: A mouse model of increased emotional lability

    OpenAIRE

    Wei, Qiang (Ethan); Lu, Xin-Yun; Liu, Li; Schafer, Gwen; Shieh, Kun-Ruey; Burke, Sharon; Robinson, Terry E; Watson, Stanley J.; Seasholtz, Audrey F.; Akil, Huda

    2004-01-01

    The molecular mechanisms that control the range and stability of emotions are unknown, yet this knowledge is critical for understanding mood disorders, especially bipolar illness. Here, we show that the glucocorticoid receptor (GR) modulates these features of emotional responsiveness. We generated transgenic mice overexpressing GR specifically in forebrain. These mice display a significant increase in anxiety-like and depressant-like behaviors relative to wild type. Yet, they are also superse...

  2. Forebrain Glucocorticoid Receptor Overexpression Increases Environmental Reactivity and Produces a Stress-Induced Spatial Discrimination Deficit

    OpenAIRE

    Hebda-Bauer, Elaine K.; Pletsch, Amy; Darwish, Hala; Fentress, Hugh; Simmons, Tracy A.; Wei, Qiang (Ethan); Watson, Stanley J.; Akil, Huda

    2010-01-01

    Reactivity to environmental stressors influences vulnerability to neurological and psychiatric illnesses, but little is known about molecular mechanisms that control this reactivity. Since mice with forebrain-specific glucocorticoid receptor overexpression (GRov mice) display anxiety-like behaviors in novel environments and have difficulty adjusting to change in memory tasks, we hypothesized that these may be facets of a broader phenotype of altered reactivity to environmental demands. Male G...

  3. Spine morphology of neurons in the Avian forebrain is affected by rearing conditions

    OpenAIRE

    Rollenhagen, Astrid; Bischof, Hans-Joachim

    1994-01-01

    An area of the caudal forebrain of male zebra finches, the Archi-Neostriatum caudale (ANC), which is active during arousal (Bischof and Herrmann, 1986, 1988), shows rearing-dependent changes in neuron morphology (Rollenhagen and Bischof, 1991). We demonstrate here that rearing conditions also affect the shape of spines of one of the four ANC neuron types. This neuron type was examined in birds reared under five different conditions - in isolation (1), caged (2), in the aviary (3), and with so...

  4. Sex differences in fear conditioning: a role of the forebrain mineralocorticoid receptor

    OpenAIRE

    ter Horst, Judith P.; Maaike H. van der Mark; E Ronald de Kloet; Oitzl, Melly S.

    2012-01-01

    Rationale : A recent study showed that a mineralocorticoid receptor (MR) gene variant, MR haplotype 2, was associated with higher levels of dispositional optimism, less thoughts of hopelessness, and lower risk of depression in women but not in men. Mice lacking the MR in the forebrain, MRCaMKCre mice, were generated to further investigate behavioral sex differences with and without the MR. Here, the hypothesis that sex differences would disappear after deletion of the MR was tested. Methods :...

  5. 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...

  6. Adaptation in the auditory system: an overview

    OpenAIRE

    David ePérez-González; Malmierca, Manuel S.

    2014-01-01

    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 s...

  7. Natural auditory scene statistics shapes human spatial hearing.

    Science.gov (United States)

    Parise, Cesare V; Knorre, Katharina; Ernst, Marc O

    2014-04-22

    Human perception, cognition, and action are laced with seemingly arbitrary mappings. In particular, sound has a strong spatial connotation: Sounds are high and low, melodies rise and fall, and pitch systematically biases perceived sound elevation. The origins of such mappings are unknown. Are they the result of physiological constraints, do they reflect natural environmental statistics, or are they truly arbitrary? We recorded natural sounds from the environment, analyzed the elevation-dependent filtering of the outer ear, and measured frequency-dependent biases in human sound localization. We find that auditory scene statistics reveals a clear mapping between frequency and elevation. Perhaps more interestingly, this natural statistical mapping is tightly mirrored in both ear-filtering properties and in perceived sound location. This suggests that both sound localization behavior and ear anatomy are fine-tuned to the statistics of natural auditory scenes, likely providing the basis for the spatial connotation of human hearing. PMID:24711409

  8. Short-term plasticity of the human auditory cortex.

    Science.gov (United States)

    Pantev, C; Wollbrink, A; Roberts, L E; Engelien, A; Lütkenhöner, B

    1999-09-18

    Magnetoencephalographic measurements (MEG) were used to examine the effect on the human auditory cortex of removing specific frequencies from the acoustic environment. Subjects listened for 3 h on three consecutive days to music "notched" by removal of a narrow frequency band centered on 1 kHz. Immediately after listening to the notched music, the neural representation for a 1-kHz test stimulus centered on the notch was found to be significantly diminished compared to the neural representation for a 0.5-kHz control stimulus centered one octave below the region of notching. The diminished neural representation for 1 kHz reversed to baseline between the successive listening sessions. These results suggest that rapid changes can occur in the tuning of neurons in the adult human auditory cortex following manipulation of the acoustic environment. A dynamic form of neural plasticity may underlie the phenomenon observed here. PMID:10526109

  9. Cell Death Atlas of the Postnatal Mouse Ventral Forebrain and Hypothalamus: Effects of Age and Sex

    Science.gov (United States)

    Ahern, Todd H.; Krug, Stefanie; Carr, Audrey V.; Murray, Elaine K.; Fitzpatrick, Emmett; Bengston, Lynn; McCutcheon, Jill; De Vries, Geert J.; Forger, Nancy G.

    2016-01-01

    Naturally occurring cell death is essential to the development of the mammalian nervous system. Although the importance of developmental cell death has been appreciated for decades, there is no comprehensive account of cell death across brain areas in the mouse. Moreover, several regional sex differences in cell death have been described for the ventral forebrain and hypothalamus, but it is not known how widespread the phenomenon is. We used immunohistochemical detection of activated caspase-3 to identify dying cells in the brains of male and female mice from postnatal day (P) 1 to P11. Cell death density, total number of dying cells, and regional volume were determined in 16 regions of the hypothalamus and ventral forebrain (the anterior hypothalamus, arcuate nucleus, anteroventral periventricular nucleus, medial preoptic nucleus, paraventricular nucleus, suprachiasmatic nucleus, and ventromedial nucleus of the hypothalamus; the basolateral, central, and medial amygdala; the lateral and principal nuclei of the bed nuclei of the stria terminalis; the caudate-putamen; the globus pallidus; the lateral septum; and the islands of Calleja). All regions showed a significant effect of age on cell death. The timing of peak cell death varied between P1 to P7, and the average rate of cell death varied tenfold among regions. Several significant sex differences in cell death and/or regional volume were detected. These data address large gaps in the developmental literature and suggest interesting region-specific differences in the prevalence and timing of cell death in the hypothalamus and ventral forebrain. PMID:23296992

  10. Forebrain neuroanatomy of the neonatal and juvenile dolphin (T. truncatus and S. coeruloalba).

    Science.gov (United States)

    Parolisi, Roberta; Peruffo, Antonella; Messina, Silvia; Panin, Mattia; Montelli, Stefano; Giurisato, Maristella; Cozzi, Bruno; Bonfanti, Luca

    2015-01-01

    Knowledge of dolphin functional neuroanatomy mostly derives from post-mortem studies and non-invasive approaches (i.e., magnetic resonance imaging), due to limitations in experimentation on cetaceans. As a consequence the availability of well-preserved tissues for histology is scarce, and detailed histological analyses are referred mainly to adults. Here we studied the neonatal/juvenile brain in two species of dolphins, the bottlenose dolphin (Tursiops truncatus) and the striped dolphin (Stenella coeruleoalba), with special reference to forebrain regions. We analyzed cell density in subcortical nuclei, white/gray matter ratio, and myelination in selected regions at different anterior-posterior levels of the whole dolphin brain at different ages, to better define forebrain neuroanatomy and the developmental stage of the dolphin brain around birth. The analyses were extended to the periventricular germinal layer and the cerebellum, whose delayed genesis of the granule cell layer is a hallmark of postnatal development in the mammalian nervous system. Our results establish an atlas of the young dolphin forebrain and, on the basis of occurrence/absence of delayed neurogenic layers, confirm the stage of advanced brain maturation in these animals with respect to most terrestrial mammals. PMID:26594155

  11. Heterogeneous patterns of oligodendroglial differentiation in the forebrain of the opossum Didelphis marsupialis.

    Science.gov (United States)

    Barradas, P C; Gomes, S S; Cavalcante, L A

    1998-01-01

    The differentiation of oligodendrocytes in the forebrain of the opossum (Didelphis marsupialis) has been studied by the immunohistochemical identification of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and by the autoradiographic detection of the uptake of 3H-thymidine. CNPase is expressed early in oligodendroglia somata and fibre sheaths (myelin) in the forebrain and its persistence in the cell bodies is regionally heterogeneous, being ephemeral in cells within the optic pathway, supraoptic decussation, and posterior commissure, of intermediate duration in the mamillo-thalamic fascicle, and stria medullaris, and long-lasting in other diencephalic and in telencephalic tracts. In the cerebral cortex, most CNPase+ cells have small somata and multiple processes (types I and II). CNPase-expressing oligodendrocytes are also regionally heterogeneous in terms of proliferative capability, which could not be detected in forebrain tracts or diencephalon, but has appeared in a small proportion of cells in the neocortical white matter and in the fimbria. Our findings provide additional evidence in favour of the heterogeneity of oligodendrocytes. PMID:9530996

  12. Alteration of forebrain neurogenesis after cervical spinal cord injury in the adult rat.

    Directory of Open Access Journals (Sweden)

    Marie-Solenne eFELIX

    2012-04-01

    Full Text Available Spinal cord injury (SCI triggers a complex cellular response at the injury site, leading to the formation of a dense scar tissue. Despite this local tissue remodeling, the consequences of SCI at the cellular level in distant rostral sites (i.e. brain, remain unknown. In this study, we asked whether cervical SCI could alter cell dynamics in neurogenic areas of the adult rat forebrain. To this aim, we quantified BrdU incorporation and determined the phenotypes of newly generated cells (neurons, astrocytes, or microglia during the subchronic and chronic phases of injury. We find that subchronic SCI leads to a reduction of BrdU incorporation and neurogenesis in the olfactory bulb and in the hippocampal dentate gyrus. By contrast, subchronic SCI triggers an increased BrdU incorporation in the dorsal vagal complex of the hindbrain, where most of the newly generated cells are identified as microglia. In chronic condition 90 days after SCI, BrdU incorporation returns to control levels in all regions examined, except in the hippocampus, where SCI produces a long-term reduction of neurogenesis, indicating that this structure is particularly sensitive to SCI. Finally, we observe that SCI triggers an acute inflammatory response in all brain regions examined, as well as a hippocampal-specific decline in BDNF levels, which could explain the SCI-mediated distant effects on forebrain neurogenesis. This study provides the first demonstration that forebrain neurogenesis is vulnerable to a distal SCI.

  13. Forebrain neuroanatomy of the neonatal and juvenile dolphin (T. truncatus & S. coeruloalba

    Directory of Open Access Journals (Sweden)

    Roberta eParolisi

    2015-11-01

    Full Text Available Knowledge of dolphin functional neuroanatomy mostly derives from post-mortem studies and non-invasive approaches (i.e. magnetic resonance imaging, due to limitations in experimentation on cetaceans. As a consequence the availability of well-preserved tissues for histology is scarce, and detailed histological analyses are referred mainly to adults. Here we studied the neonatal/juvenile brain in two species of dolphins, the bottlenose dolphin (Tursiops truncatus and the striped dolphin (Stenella coeruleoalba, with special reference to forebrain regions. We analyzed cell density in subcortical nuclei, white/grey matter ratio, and myelination in selected regions at different anterior-posterior levels of the whole dolphin brain at different ages, to better define forebrain neuroanatomy and the developmental stage of the dolphin brain around birth. The analysis were extended to the periventricular germinal layer and the cerebellum, whose delayed genesis of the granule cell layer is a hallmark of postnatal development in the mammalian nervous system. Our results establish an atlas of the young dolphin forebrain and, on the basis of occurrence/absence of delayed neurogenic layers, confirm the stage of advanced brain maturation in these animals with respect to most terrestrial mammals.

  14. Altered cholesterol biosynthesis causes precocious neurogenesis in the developing mouse forebrain.

    Science.gov (United States)

    Driver, Ashley M; Kratz, Lisa E; Kelley, Richard I; Stottmann, Rolf W

    2016-07-01

    We previously reported a mutation in the cholesterol biosynthesis gene, hydroxysteroid (17-beta) dehydrogenase 7 (Hsd17b7(rudolph)), that results in striking embryonic forebrain dysgenesis. Here we describe abnormal patterns of neuroprogenitor proliferation in the mutant forebrain, namely, a decrease in mitotic cells within the ventricular zone (VZ) and an increase through the remainder of the cortex by E11.5. Further evidence suggests mutant cells undergo abnormal interkinetic nuclear migration (IKNM). Furthermore, intermediate progenitors are increased at the expense of apical progenitors by E12.5, and post-mitotic neurons are expanded by E14.5. In vitro primary neuron culture further supports our model of accelerated cortical differentiation in the mutant. Combined administration of a statin and dietary cholesterol in utero achieved partial reversal of multiple developmental abnormalities in the Hsd17b7(rudolph) embryo, including the forebrain. These results suggest that abnormally increased levels of specific cholesterol precursors in the Hsd17b7(rudolph) embryo cause cortical dysgenesis by altering patterns of neurogenesis. PMID:26921468

  15. Visibility of speech articulation enhances auditory phonetic convergence.

    Science.gov (United States)

    Dias, James W; Rosenblum, Lawrence D

    2016-01-01

    Talkers automatically imitate aspects of perceived speech, a phenomenon known as phonetic convergence. Talkers have previously been found to converge to auditory and visual speech information. Furthermore, talkers converge more to the speech of a conversational partner who is seen and heard, relative to one who is just heard (Dias & Rosenblum Perception, 40, 1457-1466, 2011). A question raised by this finding is what visual information facilitates the enhancement effect. In the following experiments, we investigated the possible contributions of visible speech articulation to visual enhancement of phonetic convergence within the noninteractive context of a shadowing task. In Experiment 1, we examined the influence of the visibility of a talker on phonetic convergence when shadowing auditory speech either in the clear or in low-level auditory noise. The results suggest that visual speech can compensate for convergence that is reduced by auditory noise masking. Experiment 2 further established the visibility of articulatory mouth movements as being important to the visual enhancement of phonetic convergence. Furthermore, the word frequency and phonological neighborhood density characteristics of the words shadowed were found to significantly predict phonetic convergence in both experiments. Consistent with previous findings (e.g., Goldinger Psychological Review, 105, 251-279, 1998), phonetic convergence was greater when shadowing low-frequency words. Convergence was also found to be greater for low-density words, contrasting with previous predictions of the effect of phonological neighborhood density on auditory phonetic convergence (e.g., Pardo, Jordan, Mallari, Scanlon, & Lewandowski Journal of Memory and Language, 69, 183-195, 2013). Implications of the results for a gestural account of phonetic convergence are discussed. PMID:26358471

  16. Dipole source encoding and tracking by the goldfish auditory system

    OpenAIRE

    Coombs, Sheryl; Fay, Richard R.; Elepfandt, Andreas

    2010-01-01

    In goldfish and other otophysans, the Weberian ossicles mechanically link the saccule of the inner ear to the anterior swimbladder chamber (ASB). These structures are correlated with enhanced sound-pressure sensitivity and greater sensitivity at high frequencies (600–2000 Hz). However, surprisingly little is known about the potential impact of the ASB on other otolithic organs and about how auditory responses are modulated by discrete sources that change their location or orientation with res...

  17. Auditory Brainstem Circuits That Mediate the Middle Ear Muscle Reflex

    OpenAIRE

    Mukerji, Sudeep; Windsor, Alanna Marie; Lee, Daniel J.

    2010-01-01

    The middle ear muscle (MEM) reflex is one of two major descending systems to the auditory periphery. There are two middle ear muscles (MEMs): the stapedius and the tensor tympani. In man, the stapedius contracts in response to intense low frequency acoustic stimuli, exerting forces perpendicular to the stapes superstructure, increasing middle ear impedance and attenuating the intensity of sound energy reaching the inner ear (cochlea). The tensor tympani is believed to contract in response to ...

  18. Attentive, Affective, and Adaptive Behavior in the Cat: Sensory deprivation of the forebrain by lesions in the brain stem results in striking behavioral abnormalities.

    Science.gov (United States)

    Sprague, J M; Chambers, W W; Stellar, E

    1961-01-20

    Lesions of the lateral portion of the upper midbrain, involving medial, lateral, spinal, and trigeminal lemnisci primarily, result in a consistent syndrome of symptoms in the cat. (i) There is a marked sensory deficit, characterized mainly by sensory inattention and poor localization in the tactile, proprioceptive, auditory, gustatory, and nociceptive modalities, where direct pathways are interrupted. Similar defectsappear in vision and olfaction where no known direct or primary paths are interrupted. (ii) These cats are characterized by a lack of affect, showing little or no defensive and aggressive reaction to noxious and aversive situations and no response to pleasurable stimulation or solicitation of affection or petting. The animals are mute, lack facial expression, and show minimal autonomic responses. (iii) They show a hyperexploratory activity characterized by incessant, stereotyped wandering, sniffing, and visual searching, as though hallucinating. This behavior appears to be centrally directed and is very difficult to interrupt with environmental stimuli. (iv) They also demonstrate exaggerated oral activities: they snap in response to tactile stimulation of the lips, seizing and swallowing small objects even if inedible; they overeat; they hold objects too large to swallow (a mouse, a catnip ball) firmly clamped in the mouth for long periods of time; they mount and seize other animals (rat, cat, dog, monkey) by the back or the neck; they lick and chew the hair and skin of the back or tail incessantly when confined in a cage. In interpreting these results we emphasize the view that the syndrome is due chiefly to the extensive, specific, sensory deprivation produced by interruption of the lemnisci at the rostral midbrain. The relation of these findings to the effects of sensory isolation in man and animals, to the effects of midbrain lesions and neodecortication, to parietal lobe syndrome in primates, and to the behavior of autistic children is discussed

  19. On Optimality in Auditory Information Processing

    CERN Document Server

    Karlsson, M

    2000-01-01

    We study limits for the detection and estimation of weak sinusoidal signals in the primary part of the mammalian auditory system using a stochastic Fitzhugh-Nagumo (FHN) model and an action-reaction model for synaptic plasticity. Our overall model covers the chain from a hair cell to a point just after the synaptic connection with a cell in the cochlear nucleus. The information processing performance of the system is evaluated using so called phi-divergences from statistics which quantify a dissimilarity between probability measures and are intimately related to a number of fundamental limits in statistics and information theory (IT). We show that there exists a set of parameters that can optimize several important phi-divergences simultaneously and that this set corresponds to a constant quiescent firing rate (QFR) of the spiral ganglion neuron. The optimal value of the QFR is frequency dependent but is essentially independent of the amplitude of the signal (for small amplitudes). Consequently, optimal proce...

  20. Implications of blast exposure for central auditory function: A review

    Directory of Open Access Journals (Sweden)

    Frederick J. Gallun, PhD

    2012-10-01

    Full Text Available Auditory system functions, from peripheral sensitivity to central processing capacities, are all at risk from a blast event. Accurate encoding of auditory patterns in time, frequency, and space are required for a clear understanding of speech and accurate localization of sound sources in environments with background noise, multiple sound sources, and/or reverberation. Further work is needed to refine the battery of clinical tests sensitive to the sorts of central auditory dysfunction observed in individuals with blast exposure. Treatment options include low-gain hearing aids, remote-microphone technology, and auditory-training regimens, but clinical evidence does not yet exist for recommending one or more of these options. As this population ages, the natural aging process and other potential brain injuries (such as stroke and blunt trauma may combine with blast-related brain changes to produce a population for which the current clinical diagnostic and treatment tools may prove inadequate. It is important to maintain an updated understanding of the scope of the issues present in this population and to continue to identify those solutions that can provide measurable improvements in the lives of Veterans who have been exposed to high-intensity blasts during the course of their military service.

  1. Making and monitoring errors based on altered auditory feedback

    Directory of Open Access Journals (Sweden)

    Peter ePfordresher

    2014-08-01

    Full Text Available Previous research has demonstrated that altered auditory feedback (AAF disrupts music performance and causes disruptions in both action planning and the perception of feedback events. It has been proposed that this disruption occurs because of interference within a shared representation for perception and action (Pfordresher, 2006. Studies reported here address this claim from the standpoint of error monitoring. In Experiment 1 participants performed short melodies on a keyboard while hearing no auditory feedback, normal auditory feedback, or alterations to feedback pitch on some subset of events. Participants overestimated error frequency when AAF was present but not for normal feedback. Experiment 2 introduced a concurrent load task to determine whether error monitoring requires executive resources. Although the concurrent task enhanced the effect of AAF, it did not alter participants’ tendency to overestimate errors when AAF was present. A third correlational study addressed whether effects of AAF are reduced for a subset of the population who may lack the kind of perception/action associations that lead to AAF disruption: poor-pitch singers. Effects of manipulations similar to those presented in Experiments 1 and 2 were reduced for these individuals. We propose that these results are consistent with the notion that AAF interference is based on associations between perception and action within a forward internal model of auditory-motor relationships.

  2. Auditory intensity processing: Effect of MRI background noise.

    Science.gov (United States)

    Angenstein, Nicole; Stadler, Jörg; Brechmann, André

    2016-03-01

    Studies on active auditory intensity discrimination in humans showed equivocal results regarding the lateralization of processing. Whereas experiments with a moderate background found evidence for right lateralized processing of intensity, functional magnetic resonance imaging (fMRI) studies with background scanner noise suggest more left lateralized processing. With the present fMRI study, we compared the task dependent lateralization of intensity processing between a conventional continuous echo planar imaging (EPI) sequence with a loud background scanner noise and a fast low-angle shot (FLASH) sequence with a soft background scanner noise. To determine the lateralization of the processing, we employed the contralateral noise procedure. Linearly frequency modulated (FM) tones were presented monaurally with and without contralateral noise. During both the EPI and the FLASH measurement, the left auditory cortex was more strongly involved than the right auditory cortex while participants categorized the intensity of FM tones. This was shown by a strong effect of the additional contralateral noise on the activity in the left auditory cortex. This means a massive reduction in background scanner noise still leads to a significant left lateralized effect. This suggests that the reversed lateralization in fMRI studies with loud background noise in contrast to studies with softer background cannot be fully explained by the MRI background noise. PMID:26778471

  3. Tuned with a Tune: Talker Normalization via General Auditory Processes.

    Science.gov (United States)

    Laing, Erika J C; Liu, Ran; Lotto, Andrew J; Holt, Lori L

    2012-01-01

    Voices have unique acoustic signatures, contributing to the acoustic variability listeners must contend with in perceiving speech, and it has long been proposed that listeners normalize speech perception to information extracted from a talker's speech. Initial attempts to explain talker normalization relied on extraction of articulatory referents, but recent studies of context-dependent auditory perception suggest that general auditory referents such as the long-term average spectrum (LTAS) of a talker's speech similarly affect speech perception. The present study aimed to differentiate the contributions of articulatory/linguistic versus auditory referents for context-driven talker normalization effects and, more specifically, to identify the specific constraints under which such contexts impact speech perception. Synthesized sentences manipulated to sound like different talkers influenced categorization of a subsequent speech target only when differences in the sentences' LTAS were in the frequency range of the acoustic cues relevant for the target phonemic contrast. This effect was true both for speech targets preceded by spoken sentence contexts and for targets preceded by non-speech tone sequences that were LTAS-matched to the spoken sentence contexts. Specific LTAS characteristics, rather than perceived talker, predicted the results suggesting that general auditory mechanisms play an important role in effects considered to be instances of perceptual talker normalization. PMID:22737140

  4. Tuned with a tune: Talker normalization via general auditory processes

    Directory of Open Access Journals (Sweden)

    Erika J C Laing

    2012-06-01

    Full Text Available Voices have unique acoustic signatures, contributing to the acoustic variability listeners must contend with in perceiving speech, and it has long been proposed that listeners normalize speech perception to information extracted from a talker’s speech. Initial attempts to explain talker normalization relied on extraction of articulatory referents, but recent studies of context-dependent auditory perception suggest that general auditory referents such as the long-term average spectrum (LTAS of a talker’s speech similarly affect speech perception. The present study aimed to differentiate the contributions of articulatory/linguistic versus auditory referents for context-driven talker normalization effects and, more specifically, to identify the specific constraints under which such contexts impact speech perception. Synthesized sentences manipulated to sound like different talkers influenced categorization of a subsequent speech target only when differences in the sentences’ LTAS were in the frequency range of the acoustic cues relevant for the target phonemic contrast. This effect was true both for speech targets preceded by spoken sentence contexts and for targets preceded by nonspeech tone sequences that were LTAS-matched to the spoken sentence contexts. Specific LTAS characteristics, rather than perceived talker, predicted the results suggesting that general auditory mechanisms play an important role in effects considered to be instances of perceptual talker normalization.

  5. Auditory Pattern Recognition and Brief Tone Discrimination of Children with Reading Disorders

    Science.gov (United States)

    Walker, Marianna M.; Givens, Gregg D.; Cranford, Jerry L.; Holbert, Don; Walker, Letitia

    2006-01-01

    Auditory pattern recognition skills in children with reading disorders were investigated using perceptual tests involving discrimination of frequency and duration tonal patterns. A behavioral test battery involving recognition of the pattern of presentation of tone triads was used in which individual components differed in either frequency or…

  6. A review on auditory space adaptations to altered head-related cues

    Directory of Open Access Journals (Sweden)

    Catarina eMendonça

    2014-07-01

    Full Text Available In this article we present a review of current literature on adaptations to altered head-related auditory localization cues. Localization cues can be altered through ear blocks, ear molds, electronic hearing devices and altered head-related transfer functions. Three main methods have been used to induce auditory space adaptation: sound exposure, training with feedback, and explicit training. Adaptations induced by training, rather than exposure, are consistently faster. Studies on localization with altered head-related cues have reported poor initial localization, but improved accuracy and discriminability with training. Also, studies that displaced the auditory space by altering cue values reported adaptations in perceived source position to compensate for such displacements. Auditory space adaptations can last for a few months even without further contact with the learned cues. In most studies, localization with the subject’s own unaltered cues remained intact despite the adaptation to a second set of cues. Generalization is observed from trained to untrained sound source positions, but there is mixed evidence regarding cross-frequency generalization. Multiple brain areas might be involved in auditory space adaptation processes, but the auditory cortex may play a critical role. Auditory space plasticity may involve context-dependent cue reweighting.

  7. Modulation of learning and memory by the targeted deletion of the circadian clock gene Bmal1 in forebrain circuits.

    Science.gov (United States)

    Snider, Kaitlin H; Dziema, Heather; Aten, Sydney; Loeser, Jacob; Norona, Frances E; Hoyt, Kari; Obrietan, Karl

    2016-07-15

    A large body of literature has shown that the disruption of circadian clock timing has profound effects on mood, memory and complex thinking. Central to this time keeping process is the master circadian pacemaker located within the suprachiasmatic nucleus (SCN). Of note, within the central nervous system, clock timing is not exclusive to the SCN, but rather, ancillary oscillatory capacity has been detected in a wide range of cell types and brain regions, including forebrain circuits that underlie complex cognitive processes. These observations raise questions about the hierarchical and functional relationship between the SCN and forebrain oscillators, and, relatedly, about the underlying clock-gated synaptic circuitry that modulates cognition. Here, we utilized a clock knockout strategy in which the essential circadian timing gene Bmal1 was selectively deleted from excitatory forebrain neurons, whilst the SCN clock remained intact, to test the role of forebrain clock timing in learning, memory, anxiety, and behavioral despair. With this model system, we observed numerous effects on hippocampus-dependent measures of cognition. Mice lacking forebrain Bmal1 exhibited deficits in both acquisition and recall on the Barnes maze. Notably, loss of forebrain Bmal1 abrogated time-of-day dependent novel object location memory. However, the loss of Bmal1 did not alter performance on the elevated plus maze, open field assay, and tail suspension test, indicating that this phenotype specifically impairs cognition but not affect. Together, these data suggest that forebrain clock timing plays a critical role in shaping the efficiency of learning and memory retrieval over the circadian day. PMID:27091299

  8. Coding of auditory space

    OpenAIRE

    Konishi­, Masakazu

    2003-01-01

    Behavioral, anatomical, and physiological approaches can be integrated in the study of sound localization in barn owls. Space representation in owls provides a useful example for discussion of place and ensemble coding. Selectivity for space is broad and ambiguous in low-order neurons. Parallel pathways for binaural cues and for different frequency bands converge on high-order space-specific neurons, which encode space more precisely. An ensemble of broadly tuned place-coding neurons may conv...

  9. Psychophysiological reactivity to auditory Binaural Beats stimulation in the alpha and theta EEG brain-wave frequency bands: A randomized, double–blind and placebo–controlled study in human healthy young adult subjects

    OpenAIRE

    Pfaff, Hans Uwe

    2014-01-01

    Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Psicología, Departamento de Psicología Biológica y de la Salud. Fecha de lectura: 25-06-2014 Binaural beats are an acoustical illusion of the perception of a “virtual” third tone, fluctuating (i.e. beating) in its volume evoked by two carrier–sinusoids of same amplitudes, but slightly different frequencies f1 and f2, presented by stereo-headphones. Although this illusion was discovered as early as 1839 ...

  10. Psychoacoustic and cognitive aspects of auditory roughness: definitions, models, and applications

    Science.gov (United States)

    Vassilakis, Pantelis N.; Kendall, Roger A.

    2010-02-01

    The term "auditory roughness" was first introduced in the 19th century to describe the buzzing, rattling auditory sensation accompanying narrow harmonic intervals (i.e. two tones with frequency difference in the range of ~15-150Hz, presented simultaneously). A broader definition and an overview of the psychoacoustic correlates of the auditory roughness sensation, also referred to as sensory dissonance, is followed by an examination of efforts to quantify it over the past one hundred and fifty years and leads to the introduction of a new roughness calculation model and an application that automates spectral and roughness analysis of sound signals. Implementation of spectral and roughness analysis is briefly discussed in the context of two pilot perceptual experiments, designed to assess the relationship among cultural background, music performance practice, and aesthetic attitudes towards the auditory roughness sensation.

  11. 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.

  12. Vocal matching and intensity of begging calls are associated with a forebrain song circuit in a generalist brood parasite.

    Science.gov (United States)

    Liu, Wan-Chun; Rivers, James W; White, David J

    2016-06-01

    Vocalizations produced by developing young early in life have simple acoustic features and are thought to be innate. Complex forms of early vocal learning are less likely to evolve in young altricial songbirds because the forebrain vocal-learning circuit is underdeveloped during the period when early vocalizations are produced. However, selective pressure experienced in early postnatal life may lead to early vocal learning that is likely controlled by a simpler brain circuit. We found the food begging calls produced by fledglings of the brown-headed cowbird (Molothrus ater), a generalist avian brood parasite, induced the expression of several immediate early genes and early circuit innervation in a forebrain vocal-motor pathway that is later used for vocal imitation. The forebrain neural activity was correlated with vocal intensity and variability of begging calls that appears to allow cowbirds to vocally match host nestmates. The begging-induced forebrain circuits we observed in fledgling cowbirds were not detected in nonparasitic passerines, including species that are close relatives to the cowbird. The involvement of forebrain vocal circuits during fledgling begging and its association with vocal learning plasticity may be an adaptation that provides young generalist brood parasites with a flexible signaling strategy to procure food from a wide range of heterospecific host parents. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 615-625, 2016. PMID:26335154

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

    Directory of Open Access Journals (Sweden)

    Roland Schaette

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

  14. Schizophrenic patients with or without auditory hallucination in the study of fraction amplitude of low-frequency fluctuation of resting state functional magnetic resonance imaging%精神分裂症有无幻听患者静息态功能磁共振比率低频振荡振幅的研究

    Institute of Scientific and Technical Information of China (English)

    陈诚; 王高华; 王惠玲; 蒋田仔; 周媛; 吴士豪; 黄欢; 邹寄林

    2015-01-01

    核的功能活动异常,为进一步揭示幻听产生的病理生理机制提供了神经影像基础.%Objective Using the fraction amplitude of low-frequency fluctuation (fALFF) of reststating fMRI to explore the characteristics of fALFF in schizophrenia with/without auditory hallucination and understand the pathological mechanism of brain function in schizophrenia with auditory hallucinations.Methods 49 schizophrenic patients (APG) with and 23 without auditory hallucination (NPG),81 healthy volunteers (NC) were included in the study.All subjects underwent rest-stating fMRI.Values of fALFF were calculated in the tape limit ranging from 0.01 Hz to 0.08 Hz.A one-way analysis of covariance,with group as fixed factor (whole-brain corrected),was conducted and followed by post hoc pairwise comparisons.Meanwhile,pearson correlation analyses were performed to further assess the relationships between these different regions of fALFF values and the Hoffman scores in patients with auditory hallucinations.Result (1) There were different on fALFF values among 3 groups in bilateral cerebellum posterior lobe,the left caudate,the left lentiform nucleus,bilateral middle frontal gyrus,bilateral anterior cingulate (AlphaSim corrected,P<0.05,voxel>21).(2)The fALFF values:Bilateral cerebellum posterior lobe:compared with NC (-1.10±0.35,-1.26±0.38),both APG(-0.83±0.40,-0.98±0.50) and NPG(-0.55±0.41,-0.62±0.40)showed increased fALFF (t=-4.009,-3.603,both P<0.05),but APG showed decreased fALFF (t=-2.782,-2.958,both P<0.05) than NPG;The left caudate:compared with NC,both APG and NPG showed increased fALFF (t=-4.51,-1.81,both P<0.05);The left lentiform nucleus:compared with NC (-0.32±0.40),APG (0.05±0.52) showed increased fALFF(t=-6.614,P<0.01),but NPG (-0.15±0.38) showed no difference;Bilateral middle frontal gyrus:compared with NPG,both APG (t=-4.051,-3.154)and NC (t=-6.645,-5.535)showed increased fALFF (all P<0.05);Bilateral anterior cingulate:Compared with NC

  15. Adaptation in the auditory system: an overview

    Directory of Open Access Journals (Sweden)

    David Pérez-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.

  16. Conceptual priming for realistic auditory scenes and for auditory words.

    Science.gov (United States)

    Frey, Aline; Aramaki, Mitsuko; Besson, Mireille

    2014-02-01

    Two experiments were conducted using both behavioral and Event-Related brain Potentials methods to examine conceptual priming effects for realistic auditory scenes and for auditory words. Prime and target sounds were presented in four stimulus combinations: Sound-Sound, Word-Sound, Sound-Word and Word-Word. Within each combination, targets were conceptually related to the prime, unrelated or ambiguous. In Experiment 1, participants were asked to judge whether the primes and targets fit together (explicit task) and in Experiment 2 they had to decide whether the target was typical or ambiguous (implicit task). In both experiments and in the four stimulus combinations, reaction times and/or error rates were longer/higher and the N400 component was larger to ambiguous targets than to conceptually related targets, thereby pointing to a common conceptual system for processing auditory scenes and linguistic stimuli in both explicit and implicit tasks. However, fine-grained analyses also revealed some differences between experiments and conditions in scalp topography and duration of the priming effects possibly reflecting differences in the integration of perceptual and cognitive attributes of linguistic and nonlinguistic sounds. These results have clear implications for the building-up of virtual environments that need to convey meaning without words. PMID:24378910

  17. Heritability of non-speech auditory processing skills.

    Science.gov (United States)

    Brewer, Carmen C; Zalewski, Christopher K; King, Kelly A; Zobay, Oliver; Riley, Alison; Ferguson, Melanie A; Bird, Jonathan E; McCabe, Margaret M; Hood, Linda J; Drayna, Dennis; Griffith, Andrew J; Morell, Robert J; Friedman, Thomas B; Moore, David R

    2016-08-01

    Recent insight into the genetic bases for autism spectrum disorder, dyslexia, stuttering, and language disorders suggest that neurogenetic approaches may also reveal at least one etiology of auditory processing disorder (APD). A person with an APD typically has difficulty understanding speech in background noise despite having normal pure-tone hearing sensitivity. The estimated prevalence of APD may be as high as 10% in the pediatric population, yet the causes are unknown and have not been explored by molecular or genetic approaches. The aim of our study was to determine the heritability of frequency and temporal resolution for auditory signals and speech recognition in noise in 96 identical or fraternal twin pairs, aged 6-11 years. Measures of auditory processing (AP) of non-speech sounds included backward masking (temporal resolution), notched noise masking (spectral resolution), pure-tone frequency discrimination (temporal fine structure sensitivity), and nonsense syllable recognition in noise. We provide evidence of significant heritability, ranging from 0.32 to 0.74, for individual measures of these non-speech-based AP skills that are crucial for understanding spoken language. Identification of specific heritable AP traits such as these serve as a basis to pursue the genetic underpinnings of APD by identifying genetic variants associated with common AP disorders in children and adults. PMID:26883091

  18. CBP regulates the differentiation of interneurons from ventral forebrain neural precursors during murine development.

    Science.gov (United States)

    Tsui, David; Voronova, Anastassia; Gallagher, Denis; Kaplan, David R; Miller, Freda D; Wang, Jing

    2014-01-15

    The mechanisms that regulate appropriate genesis and differentiation of interneurons in the developing mammalian brain are of significant interest not only because interneurons play key roles in the establishment of neural circuitry, but also because when they are deficient, this can cause epilepsy. In this regard, one genetic syndrome that is associated with deficits in neural development and epilepsy is Rubinstein-Taybi Syndrome (RTS), where the transcriptional activator and histone acetyltransferase CBP is mutated and haploinsufficient. Here, we have asked whether CBP is necessary for the appropriate genesis and differentiation of interneurons in the murine forebrain, since this could provide an explanation for the epilepsy that is associated with RTS. We show that CBP is expressed in neural precursors within the embryonic medial ganglionic eminence (MGE), an area that generates the vast majority of interneurons for the cortex. Using primary cultures of MGE precursors, we show that knockdown of CBP causes deficits in differentiation of these precursors into interneurons and oligodendrocytes, and that overexpression of CBP is by itself sufficient to enhance interneuron genesis. Moreover, we show that levels of the neurotransmitter synthesis enzyme GAD67, which is expressed in inhibitory interneurons, are decreased in the dorsal and ventral forebrain of neonatal CBP(+/-) mice, indicating that CBP plays a role in regulating interneuron development in vivo. Thus, CBP normally acts to ensure the differentiation of appropriate numbers of forebrain interneurons, and when its levels are decreased, this causes deficits in interneuron development, providing a potential explanation for the epilepsy seen in individuals with RTS. PMID:24247009

  19. Forebrain development in fetal MRI: evaluation of anatomical landmarks before gestational week 27

    Energy Technology Data Exchange (ETDEWEB)

    Schmook, Maria T.; Weber, Michael; Kasprian, Gregor; Nemec, Stefan; Prayer, Daniela [Medical University of Vienna, Department of Radiology/Division of Neuro- and Musculoskeletal Radiology, Vienna (Austria); Brugger, Peter C. [Medical University of Vienna, Integrative Morphology Group, Center for Anatomy and Cell Biology, Vienna (Austria); Krampl-Bettelheim, Elisabeth [Department of Obstetrics and Gynecology / Division of Obstetrics and Feto-maternal Medicine, Vienna (Austria)

    2010-06-15

    Forebrain malformations include some of the most severe developmental anomalies and require early diagnosis. The proof of normal or abnormal prosencephalic development may have an influence on further management in the event of a suspected fetal malformation. The purpose of this retrospective study was to evaluate the detectability of anatomical landmarks of forebrain development using in vivo fetal magnetic resonance imaging (MRI) before gestational week (gw) 27. MRI studies of 83 singleton fetuses (gw 16-26, average {+-}sd: gw 22 {+-} 2) performed at 1.5 Tesla were assessed. T2-weighted (w) fast spin echo, T1w gradient-echo and diffusion-weighted sequences were screened for the detectability of anatomical landmarks as listed below. The interhemispheric fissure, ocular bulbs, corpus callosum, infundibulum, chiasm, septum pellucidum (SP), profile, and palate were detectable in 95%, 95%, 89%, 87%, 82%, 81%, 78%, 78% of cases. Olfactory tracts were more easily delineated than bulbs and sulci (37% versus 18% and 8%), with significantly higher detection rates in the coronal plane. The pituitary gland could be detected on T1w images in 60% with an increasing diameter with gestational age (p=0.041). The delineation of olfactory tracts (coronal plane), chiasm, SP and pituitary gland were significantly increased after week 21 (p<0.05). Pathologies were found in 28% of cases. This study provides detection rates for anatomical landmarks of forebrain development with fetal MRI before gw 27. Several anatomical structures are readily detectable with routine fetal MRI sequences; thus, if these landmarks are not delineable, it should raise the suspicion of a pathology. Recommendations regarding favorable sequences/planes are provided. (orig.)

  20. Forebrain development in fetal MRI: evaluation of anatomical landmarks before gestational week 27

    International Nuclear Information System (INIS)

    Forebrain malformations include some of the most severe developmental anomalies and require early diagnosis. The proof of normal or abnormal prosencephalic development may have an influence on further management in the event of a suspected fetal malformation. The purpose of this retrospective study was to evaluate the detectability of anatomical landmarks of forebrain development using in vivo fetal magnetic resonance imaging (MRI) before gestational week (gw) 27. MRI studies of 83 singleton fetuses (gw 16-26, average ±sd: gw 22 ± 2) performed at 1.5 Tesla were assessed. T2-weighted (w) fast spin echo, T1w gradient-echo and diffusion-weighted sequences were screened for the detectability of anatomical landmarks as listed below. The interhemispheric fissure, ocular bulbs, corpus callosum, infundibulum, chiasm, septum pellucidum (SP), profile, and palate were detectable in 95%, 95%, 89%, 87%, 82%, 81%, 78%, 78% of cases. Olfactory tracts were more easily delineated than bulbs and sulci (37% versus 18% and 8%), with significantly higher detection rates in the coronal plane. The pituitary gland could be detected on T1w images in 60% with an increasing diameter with gestational age (p=0.041). The delineation of olfactory tracts (coronal plane), chiasm, SP and pituitary gland were significantly increased after week 21 (p<0.05). Pathologies were found in 28% of cases. This study provides detection rates for anatomical landmarks of forebrain development with fetal MRI before gw 27. Several anatomical structures are readily detectable with routine fetal MRI sequences; thus, if these landmarks are not delineable, it should raise the suspicion of a pathology. Recommendations regarding favorable sequences/planes are provided. (orig.)

  1. Delta opioid receptors expressed in forebrain GABAergic neurons are responsible for SNC80-induced seizures

    Science.gov (United States)

    CHUNG, Paul CHU SIN; BOEHRER, Annie; STEPHAN, Aline; MATIFAS, Audrey; SCHERRER, Gregory; DARCQ, Emmanuel; BEFORT, Katia; KIEFFER, Brigitte L.

    2014-01-01

    The delta opioid receptor (DOR) has raised much interest for the development of new therapeutic drugs, particularly to treat patients suffering from mood disorders and chronic pain. Unfortunately, the prototypal DOR agonist SNC80 induces mild epileptic seizures in rodents. Although recently developed agonists do not seem to show convulsant properties, mechanisms and neuronal circuits that support DOR-mediated epileptic seizures remain to be clarified. DORs are expressed throughout the nervous system. In this study we tested the hypothesis that SNC80-evoked seizures stem from DOR activity at the level of forebrain GABAergic transmission, whose inhibition is known to facilitate the development of epileptic seizures. We generated a conditional DOR knockout mouse line, targeting the receptor gene specifically in GABAergic neurons of the forebrain (Dlx-DOR). We measured effects of SNC80 (4.5, 9, 13.5 and 32 mg/kg), ARM390 (10, 30 and 60 mg/kg) or ADL5859 (30, 100 and 300 mg/kg) administration on electroencephalograms (EEGs) recorded in Dlx-DOR mice and their control littermates (Ctrl mice). SNC80 produced dose-dependent seizure events in Ctrl mice, but these effects were not detected in Dlx-DOR mice. As expected, ARM390 and ADL5859 did not trigger any detectable change in mice from both genotypes. These results demonstrate for the first time that SNC80-induced DOR activation induces epileptic seizures via direct inhibition of GABAergic forebrain neurons, and supports the notion of differential activities between first and second-generation DOR agonists. PMID:25447299

  2. Comparison of cochlear delay estimates using otoacoustic emissions and auditory brainstem responses

    DEFF Research Database (Denmark)

    Harte, James; Pigasse, Gilles; Dau, Torsten

    2009-01-01

    Different attempts have been made to directly measure frequency specific basilar membrane (BM) delays in animals, e.g., laser velocimetry of BM vibrations and auditory nerve fiber recordings. The present study uses otoacoustic emissions (OAEs) and auditory brainstem responses (ABRs) to estimate B...... synaptic delays. This allows a comparison between individual OAE and BM delays over a large frequency range in the same subjects, and offers support to the theory that OAEs are reflected from a tonotopic place and carried back to the cochlear base via a reverse traveling wave....

  3. Automaticity and Primacy of Auditory Streaming: Concurrent Subjective and Objective Measures

    OpenAIRE

    Billig, Alexander J.; Robert P Carlyon

    2015-01-01

    Two experiments used subjective and objective measures to study the automaticity and primacy of auditory streaming. Listeners heard sequences of “ABA–” triplets, where “A” and “B” were tones of different frequencies and “–” was a silent gap. Segregation was more frequently reported, and rhythmically deviant triplets less well detected, for a greater between-tone frequency separation and later in the sequence. In Experiment 1, performing a competing auditory task for the first part of the sequ...

  4. Evidence that leptin-induced weight loss requires activation of both forebrain and hindbrain receptors

    OpenAIRE

    Ruth B.S. Harris

    2013-01-01

    Previous studies with chronic decerebrate rats and rats infused with leptin into the 4th ventricle suggest that hindbrain leptin receptors attenuate the catabolic effect of forebrain leptin receptor activation. To test this further rats were fitted with both 3rd and 4th ventricle cannulae. They were infused for 12 days with different combinations of saline, low dose leptin or leptin receptor antagonist (leptin mutein protein). Infusion of 0.1 μg leptin/day into the 3rd ventricle or 0.6 μg lep...

  5. The forebrain of the blind cave fish Astyanax hubbsi (Characidae). I. General anatomy of the telencephalon.

    Science.gov (United States)

    Riedel, G

    1997-01-01

    This paper presents a survey of the cell groups in the telencephalon of the teleost Astyanax hubbsi, based on series of transverse sections stained with the Nissl-Klüver-Barrera and Bodian procedures. The work was conducted for two reasons. Firstly, it was intended to determine the contribution of the forebrain of blind cave fish to certain forms of behavior. An understanding of the anatomy of the telencephalic organization is essential for such a neuroethological approach. The second purpose was to provide the cytoarchitectural basis for the experimental analysis of the fiber connectivity of the telencephalon of A. hubbsi. Furthermore, information about the forebrain of characids is widely lacking, and this study may thus provide important knowledge about the cellular organization of characid forebrains for comparative anatomists. The brain of A. hubbsi is slender and elongated. Both optic nerves and optic tectum are reduced. Three longitudinal sulci-s. ypsiliformis, s. externus and s. limitans telencephali-can be distinguished in the telencephalon. A fiber lamina reaching from the s. externus to the s. limitans telencephali separates the area dorsalis (D) from the area ventralis telencephali (V). The two hemispheres are connected by fibers decussating in the anterior commissure. Although cross sections revealed no distinct fiber laminae between cytoarchitectonic components, 17 cell masses could be delineated: ten of these belong to D, seven to V. The topological analysis yielded the following results. The dorsal telencephalon D consists of three longitudinal columns, termed pars medialis (Dm), pars dorsalis and centralis (Dd and Dc) considered together, and par lateralis (Dl), which converge into a uniform posterior part (Dp). The columns can be divided into several subregions: Dm1 and Dm2, as well as Dlv and Dld, precommissurally, Dm3 and Dm4 postcommisurally. At polus posterior levels nucleus tenia can be identified. The ventral telencephalon (V) is arranged

  6. Tolerance of nestin+ cholinergic neurons in the basal forebrain against colchicine-induced cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Jing Yu; Kaihua Guo; Dongpei Li; Jinhai Duan; Juntao Zou; Junhua Yang; Zhibin Yao

    2011-01-01

    In the present study we injected colchicine into the lateral ventricle of Sprague-Dawley rats to investigate the effects of colchicine on the number of different-type neurons in the basal forebrain and to search for neurons resistant to injury. After colchicine injection, the number of nestin+ cholinergic neurons was decreased at 1 day, but increased at 3 days and peaked at 14-28 days. The quantity of nestin- cholinergic neurons, parvalbumin-positive neurons and choline acetyl transferase-positive neurons decreased gradually. Our results indicate that nestin+ cholinergic neurons possess better tolerance to colchicine-induced neurotoxicity.

  7. Inhibition of microRNA-181 reduces forebrain ischemia-induced neuronal loss

    OpenAIRE

    Moon, Jeong-mi; Xu, Lijun; Rona G Giffard

    2013-01-01

    MicroRNA (miRNA), miR-181a, is enriched in the brain, and inhibition of miR-181a reduced astrocyte death in vitro and infarct volume after stroke in vivo. This study investigated the role of miR-181a in neuronal injury in vitro and hippocampal neuronal loss in vivo after forebrain ischemia. miR-181a levels were altered by transfection with mimic or antagomir. N2a cells subjected to serum deprivation and oxidative stress showed less cell death when miR-181a was reduced and increased death when...

  8. Classification of Underwater Target Echoes Based on Auditory Perception Characteristics

    Institute of Scientific and Technical Information of China (English)

    Xiukun Li; Xiangxia Meng; Hang Liu; Mingye Liu

    2014-01-01

    In underwater target detection, the bottom reverberation has some of the same properties as the target echo, which has a great impact on the performance. It is essential to study the difference between target echo and reverberation. In this paper, based on the unique advantage of human listening ability on objects distinction, the Gammatone filter is taken as the auditory model. In addition, time-frequency perception features and auditory spectral features are extracted for active sonar target echo and bottom reverberation separation. The features of the experimental data have good concentration characteristics in the same class and have a large amount of differences between different classes, which shows that this method can effectively distinguish between the target echo and reverberation.

  9. Directionality of auditory nerve fiber responses to pure tone stimuli in the grassfrog, Rana temporaria. I. Spike rate responses

    DEFF Research Database (Denmark)

    Jørgensen, M B; Christensen-Dalsgaard, J

    1997-01-01

    We studied the directionality of spike rate responses of auditory nerve fibers of the grassfrog, Rana temporaria, to pure tone stimuli. All auditory fibers showed spike rate directionality. The strongest directionality was seen at low frequencies (200-400 Hz), where the spike rate could change by...

  10. Psychophysiological responses to auditory change.

    Science.gov (United States)

    Chuen, Lorraine; Sears, David; McAdams, Stephen

    2016-06-01

    A comprehensive characterization of autonomic and somatic responding within the auditory domain is currently lacking. We studied whether simple types of auditory change that occur frequently during music listening could elicit measurable changes in heart rate, skin conductance, respiration rate, and facial motor activity. Participants heard a rhythmically isochronous sequence consisting of a repeated standard tone, followed by a repeated target tone that changed in pitch, timbre, duration, intensity, or tempo, or that deviated momentarily from rhythmic isochrony. Changes in all parameters produced increases in heart rate. Skin conductance response magnitude was affected by changes in timbre, intensity, and tempo. Respiratory rate was sensitive to deviations from isochrony. Our findings suggest that music researchers interpreting physiological responses as emotional indices should consider acoustic factors that may influence physiology in the absence of induced emotions. PMID:26927928

  11. Auditory distraction and serial memory

    OpenAIRE

    Jones, D M; Hughes, Rob; Macken, W.J.

    2010-01-01

    One mental activity that is very vulnerable to auditory distraction is serial recall. This review of the contemporary findings relating to serial recall charts the key determinants of distraction. It is evident that there is one form of distraction that is a joint product of the cognitive characteristics of the task and of the obligatory cognitive processing of the sound. For sequences of sound, distraction appears to be an ineluctable product of similarity-of-process, specifically, the seria...

  12. Auditory learning: a developmental method.

    Science.gov (United States)

    Zhang, Yilu; Weng, Juyang; Hwang, Wey-Shiuan

    2005-05-01

    Motivated by the human autonomous development process from infancy to adulthood, we have built a robot that develops its cognitive and behavioral skills through real-time interactions with the environment. We call such a robot a developmental robot. In this paper, we present the theory and the architecture to implement a developmental robot and discuss the related techniques that address an array of challenging technical issues. As an application, experimental results on a real robot, self-organizing, autonomous, incremental learner (SAIL), are presented with emphasis on its audition perception and audition-related action generation. In particular, the SAIL robot conducts the auditory learning from unsegmented and unlabeled speech streams without any prior knowledge about the auditory signals, such as the designated language or the phoneme models. Neither available before learning starts are the actions that the robot is expected to perform. SAIL learns the auditory commands and the desired actions from physical contacts with the environment including the trainers. PMID:15940990

  13. Auditory sequence analysis and phonological skill.

    Science.gov (United States)

    Grube, Manon; Kumar, Sukhbinder; Cooper, Freya E; Turton, Stuart; Griffiths, Timothy D

    2012-11-01

    This work tests the relationship between auditory and phonological skill in a non-selected cohort of 238 school students (age 11) with the specific hypothesis that sound-sequence analysis would be more relevant to phonological skill than the analysis of basic, single sounds. Auditory processing was assessed across the domains of pitch, time and timbre; a combination of six standard tests of literacy and language ability was used to assess phonological skill. A significant correlation between general auditory and phonological skill was demonstrated, plus a significant, specific correlation between measures of phonological skill and the auditory analysis of short sequences in pitch and time. The data support a limited but significant link between auditory and phonological ability with a specific role for sound-sequence analysis, and provide a possible new focus for auditory training strategies to aid language development in early adolescence. PMID:22951739

  14. Development of Receiver Stimulator for Auditory Prosthesis

    OpenAIRE

    K. Raja Kumar; P. Seetha Ramaiah

    2010-01-01

    The Auditory Prosthesis (AP) is an electronic device that can provide hearing sensations to people who are profoundly deaf by stimulating the auditory nerve via an array of electrodes with an electric current allowing them to understand the speech. The AP system consists of two hardware functional units such as Body Worn Speech Processor (BWSP) and Receiver Stimulator. The prototype model of Receiver Stimulator for Auditory Prosthesis (RSAP) consists of Speech Data Decoder, DAC, ADC, constant...

  15. Auditory stimulation and cardiac autonomic regulation

    OpenAIRE

    Vitor E Valenti; Guida, Heraldo L.; Frizzo, Ana C F; Cardoso, Ana C. V.; Vanderlei, Luiz Carlos M; Luiz Carlos de Abreu

    2012-01-01

    Previous studies have already demonstrated that auditory stimulation with music influences the cardiovascular system. In this study, we described the relationship between musical auditory stimulation and heart rate variability. Searches were performed with the Medline, SciELO, Lilacs and Cochrane databases using the following keywords: "auditory stimulation", "autonomic nervous system", "music" and "heart rate variability". The selected studies indicated that there is a strong correlation bet...

  16. Behavioural and neural correlates of auditory attention

    OpenAIRE

    Roberts, Katherine Leonie

    2005-01-01

    The auditory attention skills of alterting, orienting, and executive control were assessed using behavioural and neuroimaging techniques. Initially, an auditory analgue of the visual attention network test (ANT) (FAN, McCandliss, Sommer, Raz, & Posner, 2002) was created and tested alongside the visual ANT in a group of 40 healthy subjects. The results from this study showed similarities between auditory and visual spatial orienting. An fMRI study was conducted to investigate whether the simil...

  17. Distribution of neurotensin/neuromedin N mRNA in rat forebrain: unexpected abundance in hippocampus and subiculum.

    OpenAIRE

    Alexander, M J; Miller, M.A.; Dorsa, D M; Bullock, B P; Melloni, R H; Dobner, P R; Leeman, S E

    1989-01-01

    We have used in situ hybridization to determine the regional distribution of mRNA encoding the neurotensin/neuromedin N (NT/N) precursor in the forebrain of the adult male rat. Cells containing NT/N mRNA are widely distributed in the forebrain. These areas include the septum, bed nucleus of the stria terminalis, preoptic area, hypothalamus, amygdala, accumbens nucleus, caudate-putamen, and piriform and retrosplenial cortex. In general, the regional distribution of NT/N mRNA corresponds to the...

  18. Effects of Methylphenidate (Ritalin) on Auditory Performance in Children with Attention and Auditory Processing Disorders.

    Science.gov (United States)

    Tillery, Kim L.; Katz, Jack; Keller, Warren D.

    2000-01-01

    A double-blind, placebo-controlled study examined effects of methylphenidate (Ritalin) on auditory processing in 32 children with both attention deficit hyperactivity disorder and central auditory processing (CAP) disorder. Analyses revealed that Ritalin did not have a significant effect on any of the central auditory processing measures, although…

  19. Seeing the song: left auditory structures may track auditory-visual dynamic alignment.

    Directory of Open Access Journals (Sweden)

    Julia A Mossbridge

    Full Text Available Auditory and visual signals generated by a single source tend to be temporally correlated, such as the synchronous sounds of footsteps and the limb movements of a walker. Continuous tracking and comparison of the dynamics of auditory-visual streams is thus useful for the perceptual binding of information arising from a common source. Although language-related mechanisms have been implicated in the tracking of speech-related auditory-visual signals (e.g., speech sounds and lip movements, it is not well known what sensory mechanisms generally track ongoing auditory-visual synchrony for non-speech signals in a complex auditory-visual environment. To begin to address this question, we used music and visual displays that varied in the dynamics of multiple features (e.g., auditory loudness and pitch; visual luminance, color, size, motion, and organization across multiple time scales. Auditory activity (monitored using auditory steady-state responses, ASSR was selectively reduced in the left hemisphere when the music and dynamic visual displays were temporally misaligned. Importantly, ASSR was not affected when attentional engagement with the music was reduced, or when visual displays presented dynamics clearly dissimilar to the music. These results appear to suggest that left-lateralized auditory mechanisms are sensitive to auditory-visual temporal alignment, but perhaps only when the dynamics of auditory and visual streams are similar. These mechanisms may contribute to correct auditory-visual binding in a busy sensory environment.

  20. Seeing the song: left auditory structures may track auditory-visual dynamic alignment.

    Science.gov (United States)

    Mossbridge, Julia A; Grabowecky, Marcia; Suzuki, Satoru

    2013-01-01

    Auditory and visual signals generated by a single source tend to be temporally correlated, such as the synchronous sounds of footsteps and the limb movements of a walker. Continuous tracking and comparison of the dynamics of auditory-visual streams is thus useful for the perceptual binding of information arising from a common source. Although language-related mechanisms have been implicated in the tracking of speech-related auditory-visual signals (e.g., speech sounds and lip movements), it is not well known what sensory mechanisms generally track ongoing auditory-visual synchrony for non-speech signals in a complex auditory-visual environment. To begin to address this question, we used music and visual displays that varied in the dynamics of multiple features (e.g., auditory loudness and pitch; visual luminance, color, size, motion, and organization) across multiple time scales. Auditory activity (monitored using auditory steady-state responses, ASSR) was selectively reduced in the left hemisphere when the music and dynamic visual displays were temporally misaligned. Importantly, ASSR was not affected when attentional engagement with the music was reduced, or when visual displays presented dynamics clearly dissimilar to the music. These results appear to suggest that left-lateralized auditory mechanisms are sensitive to auditory-visual temporal alignment, but perhaps only when the dynamics of auditory and visual streams are similar. These mechanisms may contribute to correct auditory-visual binding in a busy sensory environment. PMID:24194873

  1. Corticofugal modulation of peripheral auditory responses

    Directory of Open Access Journals (Sweden)

    Paul Hinckley Delano

    2015-09-01

    Full Text Available The auditory efferent system originates in the auditory cortex and projects to the medial geniculate body, inferior colliculus, cochlear nucleus and superior olivary complex reaching the cochlea through olivocochlear fibers. This unique neuronal network is organized in several afferent-efferent feedback loops including: the (i colliculo-thalamic-cortico-collicular, (ii cortico-(collicular-olivocochlear and (iii cortico-(collicular-cochlear nucleus pathways. Recent experiments demonstrate that blocking ongoing auditory-cortex activity with pharmacological and physical methods modulates the amplitude of cochlear potentials. In addition, auditory-cortex microstimulation independently modulates cochlear sensitivity and the strength of the olivocochlear reflex. In this mini-review, anatomical and physiological evidence supporting the presence of a functional efferent network from the auditory cortex to the cochlear receptor is presented. Special emphasis is given to the corticofugal effects on initial auditory processing, that is, on cochlear nucleus, auditory nerve and cochlear responses. A working model of three parallel pathways from the auditory cortex to the cochlea and auditory nerve is proposed.

  2. Corticofugal modulation of peripheral auditory responses.

    Science.gov (United States)

    Terreros, Gonzalo; Delano, Paul H

    2015-01-01

    The auditory efferent system originates in the auditory cortex and projects to the medial geniculate body (MGB), inferior colliculus (IC), cochlear nucleus (CN) and superior olivary complex (SOC) reaching the cochlea through olivocochlear (OC) fibers. This unique neuronal network is organized in several afferent-efferent feedback loops including: the (i) colliculo-thalamic-cortico-collicular; (ii) cortico-(collicular)-OC; and (iii) cortico-(collicular)-CN pathways. Recent experiments demonstrate that blocking ongoing auditory-cortex activity with pharmacological and physical methods modulates the amplitude of cochlear potentials. In addition, auditory-cortex microstimulation independently modulates cochlear sensitivity and the strength of the OC reflex. In this mini-review, anatomical and physiological evidence supporting the presence of a functional efferent network from the auditory cortex to the cochlear receptor is presented. Special emphasis is given to the corticofugal effects on initial auditory processing, that is, on CN, auditory nerve and cochlear responses. A working model of three parallel pathways from the auditory cortex to the cochlea and auditory nerve is proposed. PMID:26483647

  3. Agmatine protection against chlorpromazine-induced forebrain cortex injury in rats.

    Science.gov (United States)

    Dejanovic, Bratislav; Stevanovic, Ivana; Ninkovic, Milica; Stojanovic, Ivana; Lavrnja, Irena; Radicevic, Tatjana; Pavlovic, Milos

    2016-03-01

    This study was conducted to investigate whether agmatine (AGM) provides protection against oxidative stress induced by treatment with chlorpromazine (CPZ) in Wistar rats. In addition, the role of reactive oxygen species and efficiency of antioxidant protection in the brain homogenates of forebrain cortexes prepared 48 h after treatment were investigated. Chlorpromazine was applied intraperitoneally (i.p.) in single dose of 38.7 mg/kg body weight (BW) The second group was treated with both CPZ and AGM (75 mg/kg BW). The control group was treated with 0.9% saline solution in the same manner. All tested compounds were administered i.p. in a single dose. Rats were sacrificed by decapitation 48 h after treatment Treatment with AGM significantly attenuated the oxidative stress parameters and restored antioxidant capacity in the forebrain cortex. The data indicated that i.p. administered AGM exerted antioxidant action in CPZ-treated animals. Moreover, reactive astrocytes and microglia may contribute to secondary nerve-cell damage and participate in the balance of destructive vs. protective actions involved in the pathogenesis after poisoning. PMID:27051340

  4. Regulation of a remote Shh forebrain enhancer by the Six3 homeoprotein.

    Science.gov (United States)

    Jeong, Yongsu; Leskow, Federico Coluccio; El-Jaick, Kenia; Roessler, Erich; Muenke, Maximilian; Yocum, Anastasia; Dubourg, Christele; Li, Xue; Geng, Xin; Oliver, Guillermo; Epstein, Douglas J

    2008-11-01

    In humans, SHH haploinsufficiency results in holoprosencephaly (HPE), a defect in anterior midline formation. Despite the importance of maintaining SHH transcript levels above a critical threshold, we know little about the upstream regulators of SHH expression in the forebrain. Here we describe a rare nucleotide variant located 460 kb upstream of SHH in an individual with HPE that resulted in the loss of Shh brain enhancer-2 (SBE2) activity in the hypothalamus of transgenic mouse embryos. Using a DNA affinity-capture assay, we screened the SBE2 sequence for DNA-binding proteins and identified members of the Six3 and Six6 homeodomain family as candidate regulators of Shh transcription. Six3 showed reduced binding affinity for the mutant compared to the wild-type SBE2 sequence. Moreover, Six3 with HPE-causing alterations failed to bind and activate SBE2. These data suggest a direct link between Six3 and Shh regulation during normal forebrain development and in the pathogenesis of HPE. PMID:18836447

  5. A method of basal forebrain anatomical standardization for functional image analysis.

    Science.gov (United States)

    Buchsbaum, M S; Fallon, J H; Wei, T C; Guich, S; Spiegel-Cohen, J; Hamilton, M; Tang, C

    1998-12-14

    Functional as well as structural assessment of the basal forebrain has mostly focused on the dorsal caudate and putamen in axial slices where they are easily outlined or their centers located with stereotaxic methods. The more ventral extent of the basal forebrain, where the irregular form and indistinct boundaries of the nucleus accumbens and substantia innominata are difficult to trace and where the brain's ventral surface may contribute partial volume artifacts to measurement, has been less studied. We present a method based on coronal sections, landmarks placed on clearly visible anchor points, and the computational technique of thin-plate spline warping which allows the alignment of groups of individuals to common coordinates for pixel-by-pixel statistical mapping. The reliability of the landmarks across independent raters yields a median absolute difference of 1.3-1.6 mm. The validity of the method is confirmed by variance maps which reveal significant decreases in variance over spindle and bounding box alignment. PMID:10710168

  6. Norepinephrine is necessary for experience-dependent plasticity in the developing mouse auditory cortex.

    Science.gov (United States)

    Shepard, Kathryn N; Liles, L Cameron; Weinshenker, David; Liu, Robert C

    2015-02-11

    Critical periods are developmental windows during which the stimuli an animal encounters can reshape response properties in the affected system to a profound degree. Despite this window's importance, the neural mechanisms that regulate it are not completely understood. Pioneering studies in visual cortex initially indicated that norepinephrine (NE) permits ocular dominance column plasticity during the critical period, but later research has suggested otherwise. More recent work implicating NE in experience-dependent plasticity in the adult auditory cortex led us to re-examine the role of NE in critical period plasticity. Here, we exposed dopamine β-hydroxylase knock-out (Dbh(-/-)) mice, which lack NE completely from birth, to a biased acoustic environment during the auditory cortical critical period. This manipulation led to a redistribution of best frequencies (BFs) across auditory cortex in our control mice, consistent with prior work. By contrast, Dbh(-/-) mice failed to exhibit the expected redistribution of BFs, even though NE-deficient and NE-competent mice showed comparable auditory cortical organization when reared in a quiet colony environment. These data suggest that while intrinsic tonotopic patterning of auditory cortical circuitry occurs independently from NE, NE is required for critical period plasticity in auditory cortex. PMID:25673838

  7. The Experience of Patients with Schizophrenia Treated with Repetitive Transcranial Magnetic Stimulation for Auditory Hallucinations

    Directory of Open Access Journals (Sweden)

    Priya Subramanian

    2013-01-01

    Full Text Available Introduction. Auditory hallucinations are a common symptom experience of individuals with psychotic disorders and are often experienced as persistent, distressing, and disruptive. This case series examined the lived experiences of four individuals treated (successfully or unsuccessfully with low-frequency (1 Hz rTMS for auditory hallucinations. Methods. A phenomenological approach was used and modified to involve some predetermined data structuring to accommodate for expected cognitive impairments of participants and the impact of rTMS on auditory hallucinations. Data on thoughts and feelings in relation to the helpful, unhelpful, and other effects of rTMS on auditory hallucinations, on well-being, functioning, and the immediate environment were collected using semistructured interviews. Results. All four participants noted some improvements in their well-being following treatment and none reported a worsening of their symptoms. Only two participants noted an improvement in the auditory hallucinations and only one of them reported an improvement that was sustained after treatment completion. Conclusion. We suggest that there are useful findings in the study worth further exploration, specifically in relation to the role of an individual’s acceptance and ownership of the illness process in relation to this biomedical intervention. More mixed methods research is required to examine rTMS for auditory hallucinations.

  8. Estimating individual listeners’ auditory-filter bandwidth in simultaneous and non-simultaneous masking

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Caminade, Sabine; Strelcyk, Olaf;

    2010-01-01

    Frequency selectivity in the human auditory system is often measured using simultaneous masking of tones presented in notched noise. Based on such masking data, the equivalent rectangular bandwidth (ERB) of the auditory filters can be derived by applying the power spectrum model of masking...... and assuming a rounded-exponential filter shape. If a forward masking paradigm is used instead of simultaneous masking, filter estimates typically show significantly sharper tuning. This difference in frequency selectivity has commonly been related to spectral suppression mechanisms observed in the cochlea...... the reliability of the individual estimates, a statistical resampling method is applied. It is demonstrated that a rather large set of experimental data is required to reliably estimate auditory filter bandwidth, particularly in the case of simultaneous masking. The poor overall reliability of the filter...

  9. Evolutionary adaptations for the temporal processing of natural sounds by the anuran peripheral auditory system.

    Science.gov (United States)

    Schrode, Katrina M; Bee, Mark A

    2015-03-01

    Sensory systems function most efficiently when processing natural stimuli, such as vocalizations, and it is thought that this reflects evolutionary adaptation. Among the best-described examples of evolutionary adaptation in the auditory system are the frequent matches between spectral tuning in both the peripheral and central auditory systems of anurans (frogs and toads) and the frequency spectra of conspecific calls. Tuning to the temporal properties of conspecific calls is less well established, and in anurans has so far been documented only in the central auditory system. Using auditory-evoked potentials, we asked whether there are species-specific or sex-specific adaptations of the auditory systems of gray treefrogs (Hyla chrysoscelis) and green treefrogs (H. cinerea) to the temporal modulations present in conspecific calls. Modulation rate transfer functions (MRTFs) constructed from auditory steady-state responses revealed that each species was more sensitive than the other to the modulation rates typical of conspecific advertisement calls. In addition, auditory brainstem responses (ABRs) to paired clicks indicated relatively better temporal resolution in green treefrogs, which could represent an adaptation to the faster modulation rates present in the calls of this species. MRTFs and recovery of ABRs to paired clicks were generally similar between the sexes, and we found no evidence that males were more sensitive than females to the temporal modulation patterns characteristic of the aggressive calls used in male-male competition. Together, our results suggest that efficient processing of the temporal properties of behaviorally relevant sounds begins at potentially very early stages of the anuran auditory system that include the periphery. PMID:25617467

  10. Auditory hallucinations suppressed by etizolam in a patient with schizophrenia.

    Science.gov (United States)

    Benazzi, F; Mazzoli, M; Rossi, E

    1993-10-01

    A patient presented with a 15 year history of schizophrenia with auditory hallucinations. Though unresponsive to prolonged trials of neuroleptics, the auditory hallucinations disappeared with etizolam. PMID:7902201

  11. Perception of auditory, visual, and egocentric spatial alignment adapts differently to changes in eye position.

    Science.gov (United States)

    Cui, Qi N; Razavi, Babak; O'Neill, William E; Paige, Gary D

    2010-02-01

    Vision and audition represent the outside world in spatial synergy that is crucial for guiding natural activities. Input conveying eye-in-head position is needed to maintain spatial congruence because the eyes move in the head while the ears remain head-fixed. Recently, we reported that the human perception of auditory space shifts with changes in eye position. In this study, we examined whether this phenomenon is 1) dependent on a visual fixation reference, 2) selective for frequency bands (high-pass and low-pass noise) related to specific auditory spatial channels, 3) matched by a shift in the perceived straight-ahead (PSA), and 4) accompanied by a spatial shift for visual and/or bimodal (visual and auditory) targets. Subjects were tested in a dark echo-attenuated chamber with their heads fixed facing a cylindrical screen, behind which a mobile speaker/LED presented targets across the frontal field. Subjects fixated alternating reference spots (0, +/-20 degrees ) horizontally or vertically while either localizing targets or indicating PSA using a laser pointer. Results showed that the spatial shift induced by ocular eccentricity is 1) preserved for auditory targets without a visual fixation reference, 2) generalized for all frequency bands, and thus all auditory spatial channels, 3) paralleled by a shift in PSA, and 4) restricted to auditory space. Findings are consistent with a set-point control strategy by which eye position governs multimodal spatial alignment. The phenomenon is robust for auditory space and egocentric perception, and highlights the importance of controlling for eye position in the examination of spatial perception and behavior. PMID:19846626

  12. Dissociation of detection and discrimination of pure tones following bilateral lesions of auditory cortex.

    Directory of Open Access Journals (Sweden)

    Andrew R Dykstra

    Full Text Available It is well known that damage to the peripheral auditory system causes deficits in tone detection as well as pitch and loudness perception across a wide range of frequencies. However, the extent to which to which the auditory cortex plays a critical role in these basic aspects of spectral processing, especially with regard to speech, music, and environmental sound perception, remains unclear. Recent experiments indicate that primary auditory cortex is necessary for the normally-high perceptual acuity exhibited by humans in pure-tone frequency discrimination. The present study assessed whether the auditory cortex plays a similar role in the intensity domain and contrasted its contribution to sensory versus discriminative aspects of intensity processing. We measured intensity thresholds for pure-tone detection and pure-tone loudness discrimination in a population of healthy adults and a middle-aged man with complete or near-complete lesions of the auditory cortex bilaterally. Detection thresholds in his left and right ears were 16 and 7 dB HL, respectively, within clinically-defined normal limits. In contrast, the intensity threshold for monaural loudness discrimination at 1 kHz was 6.5 ± 2.1 dB in the left ear and 6.5 ± 1.9 dB in the right ear at 40 dB sensation level, well above the means of the control population (left ear: 1.6 ± 0.22 dB; right ear: 1.7 ± 0.19 dB. The results indicate that auditory cortex lowers just-noticeable differences for loudness discrimination by approximately 5 dB but is not necessary for tone detection in quiet. Previous human and Old-world monkey experiments employing lesion-effect, neurophysiology, and neuroimaging methods to investigate the role of auditory cortex in intensity processing are reviewed.

  13. Auditory Neural Prostheses – A Window to the Future

    Directory of Open Access Journals (Sweden)

    Mohan Kameshwaran

    2015-06-01

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

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

    Directory of Open Access Journals (Sweden)

    HeatherLChapin

    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.

  15. Narrow, duplicated internal auditory canal

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-05-01

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

  16. Auditory brainstem response in dolphins.

    OpenAIRE

    Ridgway, S. H.; Bullock, T H; Carder, D.A.; Seeley, R L; Woods, D.; Galambos, R

    1981-01-01

    We recorded the auditory brainstem response (ABR) in four dolphins (Tursiops truncatus and Delphinus delphis). The ABR evoked by clicks consists of seven waves within 10 msec; two waves often contain dual peaks. The main waves can be identified with those of humans and laboratory mammals; in spite of a much longer path, the latencies of the peaks are almost identical to those of the rat. The dolphin ABR waves increase in latency as the intensity of a sound decreases by only 4 microseconds/dec...

  17. Mismatch responses in the awake rat: evidence from epidural recordings of auditory cortical fields.

    Directory of Open Access Journals (Sweden)

    Fabienne Jung

    Full Text Available Detecting sudden environmental changes is crucial for the survival of humans and animals. In the human auditory system the mismatch negativity (MMN, a component of auditory evoked potentials (AEPs, reflects the violation of predictable stimulus regularities, established by the previous auditory sequence. Given the considerable potentiality of the MMN for clinical applications, establishing valid animal models that allow for detailed investigation of its neurophysiological mechanisms is important. Rodent studies, so far almost exclusively under anesthesia, have not provided decisive evidence whether an MMN analogue exists in rats. This may be due to several factors, including the effect of anesthesia. We therefore used epidural recordings in awake black hooded rats, from two auditory cortical areas in both hemispheres, and with bandpass filtered noise stimuli that were optimized in frequency and duration for eliciting MMN in rats. Using a classical oddball paradigm with frequency deviants, we detected mismatch responses at all four electrodes in primary and secondary auditory cortex, with morphological and functional properties similar to those known in humans, i.e., large amplitude biphasic differences that increased in amplitude with decreasing deviant probability. These mismatch responses significantly diminished in a control condition that removed the predictive context while controlling for presentation rate of the deviants. While our present study does not allow for disambiguating precisely the relative contribution of adaptation and prediction error processing to the observed mismatch responses, it demonstrates that MMN-like potentials can be obtained in awake and unrestrained rats.

  18. Auditory Perception, Suprasegmental Speech Processing, and Vocabulary Development in Chinese Preschoolers.

    Science.gov (United States)

    Wang, Hsiao-Lan S; Chen, I-Chen; Chiang, Chun-Han; Lai, Ying-Hui; Tsao, Yu

    2016-10-01

    The current study examined the associations between basic auditory perception, speech prosodic processing, and vocabulary development in Chinese kindergartners, specifically, whether early basic auditory perception may be related to linguistic prosodic processing in Chinese Mandarin vocabulary acquisition. A series of language, auditory, and linguistic prosodic tests were given to 100 preschool children who had not yet learned how to read Chinese characters. The results suggested that lexical tone sensitivity and intonation production were significantly correlated with children's general vocabulary abilities. In particular, tone awareness was associated with comprehensive language development, whereas intonation production was associated with both comprehensive and expressive language development. Regression analyses revealed that tone sensitivity accounted for 36% of the unique variance in vocabulary development, whereas intonation production accounted for 6% of the variance in vocabulary development. Moreover, auditory frequency discrimination was significantly correlated with lexical tone sensitivity, syllable duration discrimination, and intonation production in Mandarin Chinese. Also it provided significant contributions to tone sensitivity and intonation production. Auditory frequency discrimination may indirectly affect early vocabulary development through Chinese speech prosody. PMID:27519239

  19. Reducing auditory hypersensitivities in autistic spectrum disorders: Preliminary findings evaluating the Listening Project Protocol

    Directory of Open Access Journals (Sweden)

    Stephen W Porges

    2014-08-01

    Full Text Available Auditory hypersensitivities are a common feature of autism spectrum disorder (ASD. In the present study the effectiveness of a novel intervention, the Listening Project Protocol (LPP was evaluated in two trials conducted with children diagnosed with ASD. LPP was developed to reduce auditory hypersensitivities. LPP is based on a theoretical neural exercise model that uses computer altered acoustic stimulation to recruit the neural regulation of middle ear muscles. Features of the intervention stimuli were informed by basic research in speech and hearing sciences that has identified the specific acoustic frequencies necessary to understand speech, which must pass through middle ear structures before being processed by other components of the auditory system. LPP was hypothesized to reduce auditory hypersensitivities by increasing the neural tone to the middle ear muscles to functionally dampen competing sounds in frequencies lower than human speech. The trials demonstrated that LPP, when contrasted to control conditions, selectively reduced auditory hypersensitivities. These findings are consistent with the Polyvagal Theory, which emphasizes the role of the middle ear muscles in social communication.

  20. Auditory Processing Disorder and Foreign Language Acquisition

    Science.gov (United States)

    Veselovska, Ganna

    2015-01-01

    This article aims at exploring various strategies for coping with the auditory processing disorder in the light of foreign language acquisition. The techniques relevant to dealing with the auditory processing disorder can be attributed to environmental and compensatory approaches. The environmental one involves actions directed at creating a…

  1. The acute effects of alcohol on auditory thresholds

    Directory of Open Access Journals (Sweden)

    El Maaytah Mohammed

    2007-09-01

    Full Text Available Abstract Background There is very little knowledge about alcohol-induced hearing loss. Alcohol consumption and tolerance to loud noise is a well observed phenomenon as seen in the Western world where parties get noisier by the hour as the evening matures. This leads to increase in the referrals to the "hearing aid clinic" and the diagnosis of "cocktail party deafness" which may not necessarily be only due to presbyacusis or noise-induced hearing loss. Methods 30 healthy volunteers were recruited for this trial which took place in a controlled acoustic environment. Each of the individuals was required to consume a pre-set amount of alcohol and the hearing was tested (using full pure tone audiogram pre- and post- alcohol consumption over a broad range of 6 frequencies. Volunteers who achieve a minimum breath alcohol threshold level of 30 u/l had to have second audiogram testing. All the volunteers underwent timed psychometric and visuo-spatial skills tests to detect the effect of alcohol on the decision-making and psychomotor co-ordination. Results Our results showed that there was a positive association between increasing breath alcohol concentration and the magnitude of the increase in hearing threshold for most hearing frequencies. This was calculated by using the Pearson Regression Coefficient Ratio which was up to 0.6 for hearing at 1000 Hz. Over 90% of subjects had raised auditory thresholds in three or more frequencies; this was more marked in the lower frequencies. Conclusion Alcohol specifically blunts lower frequencies affecting the mostly 1000 Hz, which is the most crucial frequency for speech discrimination. In conclusion alcohol does appear to affect auditory thresholds with some frequencies being more affected than others.

  2. Distribution of neurotensin/neuromedin N mRNA in rat forebrain: Unexpected abundance in hippocampus and subiculum

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, M.J.; Miller, M.A.; Dorsa, D.M.; Bullock, B.P.; Helloni, R.H. Jr.; Dobner, P.R.; Leeman, S.E. (Univ. of Massachusetts Medical Center, Worcester (USA))

    1989-07-01

    The authors have used in situ hybridization to determine the regional distribution of mRNA encoding the neurotensin/neuromedin N (NT/N) precursor in the forebrain of the adult male rat. Cells containing NT/N mRNA are widely distributed in the forebrain. These areas include the septum, bed nucleus of the stria terminalis, preoptic area, hypothalamus, amygdala, accumbens nucleus, caudate-putamen, and piriform and retrosplenial cortex. In general, the regional distribution of NT/N mRNA corresponds to the previously determined distribution of neurotensin-immunoreactive cell bodies; however, several notable exceptions were observed. The most striking difference occurs specifically in the CA1 region of the hippocampus, where intense labeling is associated with the pyramidal cell layer despite the reported absence of neurotensin-immunoreactive cells in this region. A second major discrepancy between NT/N mRNA abundance and neurotensin-immunoreactivity occurs in the intensely labeled subiculum, a region that contains only scattered neurotensin-immunoreactive cells in the adult. These results suggest that, in specific regions of the forebrain, NT/N precursor is processed to yield products other than neurotensin. In addition, these results provide an anatomical basis for studying the physiological regulation of NT/N mRNA levels in the forebrain.

  3. Distribution of neurotensin/neuromedin N mRNA in rat forebrain: Unexpected abundance in hippocampus and subiculum

    International Nuclear Information System (INIS)

    The authors have used in situ hybridization to determine the regional distribution of mRNA encoding the neurotensin/neuromedin N (NT/N) precursor in the forebrain of the adult male rat. Cells containing NT/N mRNA are widely distributed in the forebrain. These areas include the septum, bed nucleus of the stria terminalis, preoptic area, hypothalamus, amygdala, accumbens nucleus, caudate-putamen, and piriform and retrosplenial cortex. In general, the regional distribution of NT/N mRNA corresponds to the previously determined distribution of neurotensin-immunoreactive cell bodies; however, several notable exceptions were observed. The most striking difference occurs specifically in the CA1 region of the hippocampus, where intense labeling is associated with the pyramidal cell layer despite the reported absence of neurotensin-immunoreactive cells in this region. A second major discrepancy between NT/N mRNA abundance and neurotensin-immunoreactivity occurs in the intensely labeled subiculum, a region that contains only scattered neurotensin-immunoreactive cells in the adult. These results suggest that, in specific regions of the forebrain, NT/N precursor is processed to yield products other than neurotensin. In addition, these results provide an anatomical basis for studying the physiological regulation of NT/N mRNA levels in the forebrain

  4. Developmental stress impairs performance on an association task in male and female songbirds, but impairs auditory learning in females only.

    Science.gov (United States)

    Farrell, Tara M; Morgan, Amanda; MacDougall-Shackleton, Scott A

    2016-01-01

    In songbirds, early-life environments critically shape song development. Many studies have demonstrated that developmental stress impairs song learning and the development of song-control regions of the brain in males. However, song has evolved through signaller-receiver networks and the effect stress has on the ability to receive auditory signals is equally important, especially for females who use song as an indicator of mate quality. Female song preferences have been the metric used to evaluate how developmental stress affects auditory learning, but preferences are shaped by many non-cognitive factors and preclude the evaluation of auditory learning abilities in males. To determine whether developmental stress specifically affects auditory learning in both sexes, we subjected juvenile European starlings, Sturnus vulgaris, to either an ad libitum or an unpredictable food supply treatment from 35 to 115 days of age. In adulthood, we assessed learning of both auditory and visual discrimination tasks. Females reared in the experimental group were slower than females in the control group to acquire a relative frequency auditory task, and slower than their male counterparts to acquire an absolute frequency auditory task. There was no difference in auditory performance between treatment groups for males. However, on the colour association task, birds from the experimental group committed more errors per trial than control birds. There was no correlation in performance across the cognitive tasks. Developmental stress did not affect all cognitive processes equally across the sexes. Our results suggest that the male auditory system may be more robust to developmental stress than that of females. PMID:26238792

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

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    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.

  6. Sex differences and endocrine regulation of auditory-evoked, neural responses in African clawed frogs (Xenopus).

    Science.gov (United States)

    Hall, Ian C; Woolley, Sarah M N; Kwong-Brown, Ursula; Kelley, Darcy B

    2016-01-01

    Mating depends on the accurate detection of signals that convey species identity and reproductive state. In African clawed frogs, Xenopus, this information is conveyed by vocal signals that differ in temporal patterns and spectral features between sexes and across species. We characterized spectral sensitivity using auditory-evoked potentials (AEPs), commonly known as the auditory brainstem response, in males and females of four Xenopus species. In female X. amieti, X. petersii, and X. laevis, peripheral auditory sensitivity to their species own dyad-two, species-specific dominant frequencies in the male advertisement call-is enhanced relative to males. Males were most sensitive to lower frequencies including those in the male-directed release calls. Frequency sensitivity was influenced by endocrine state; ovariectomized females had male-like auditory tuning while dihydrotestosterone-treated, ovariectomized females maintained female-like tuning. Thus, adult, female Xenopus demonstrate an endocrine-dependent sensitivity to the spectral features of conspecific male advertisement calls that could facilitate mating. Xenopus AEPs resemble those of other species in stimulus and level dependence, and in sensitivity to anesthetic (MS222). AEPs were correlated with body size and sex within some species. A frequency following response, probably encoded by the amphibian papilla, might facilitate dyad source localization via interaural time differences. PMID:26572136

  7. Auditory feedback affects perception of effort when exercising with a Pulley machine

    DEFF Research Database (Denmark)

    Bordegoni, Monica; Ferrise, Francesco; Grani, Francesco;

    2013-01-01

    In this paper we describe an experiment that investigates the role of auditory feedback in affecting the perception of effort when using a physical pulley machine. Specifically, we investigated whether variations in the amplitude and frequency content of the pulley sound affect perception of effo...

  8. Can auditory stady-state responses reflect place-specific cochlear dispersion?

    DEFF Research Database (Denmark)

    Paredes Gallardo, Andreu; Epp, Bastian; Dau, Torsten

    . Previous studies showed the applicability of auditory evoked potentials (AEP) to investigate cochlear dispersion along the basilar membrane (BM) (e.g. Dau et al., 2000). In contrast to those studies, the present study maximizes the response in a given frequency region, aiming to objectively estimate local...

  9. Prestimulus frontal-parietal coherence predicts auditory detection performance in rats

    OpenAIRE

    Herzog, Linnea; Salehi, Kia; Bohon, Kaitlin S.; Wiest, Michael C.

    2014-01-01

    Electrophysiology in primates has implicated long-range neural coherence as a potential mechanism for enhancing sensory detection. To test whether local synchronization and long-range neural coherence support detection performance in rats, we recorded local field potentials (LFPs) in frontal and parietal cortex while rats performed an auditory detection task. We observed significantly elevated power at multiple low frequencies (

  10. Tactile feedback improves auditory spatial localization.

    Science.gov (United States)

    Gori, Monica; Vercillo, Tiziana; Sandini, Giulio; Burr, David

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds before and after training, either with tactile feedback, verbal feedback, or no feedback. Audio thresholds were first measured with a spatial bisection task: subjects judged whether the second sound of a three sound sequence was spatially closer to the first or the third sound. The tactile feedback group underwent two audio-tactile feedback sessions of 100 trials, where each auditory trial was followed by the same spatial sequence played on the subject's forearm; auditory spatial bisection thresholds were evaluated after each session. In the verbal feedback condition, the positions of the sounds were verbally reported to the subject after each feedback trial. The no feedback group did the same sequence of trials, with no feedback. Performance improved significantly only after audio-tactile feedback. The results suggest that direct tactile feedback interacts with the auditory spatial localization system, possibly by a process of cross-sensory recalibration. Control tests with the subject rotated suggested that this effect occurs only when the tactile and acoustic sequences are spatially congruent. Our results suggest that the tactile system can be used to recalibrate the auditory sense of space. These results encourage the possibility of designing rehabilitation programs to help blind persons establish a robust auditory sense of space, through training with the tactile modality. PMID:25368587

  11. Tactile feedback improves auditory spatial localization

    Directory of Open Access Journals (Sweden)

    Monica eGori

    2014-10-01

    Full Text Available Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial-bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014. To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds before and after training, either with tactile feedback, verbal feedback or no feedback. Audio thresholds were first measured with a spatial bisection task: subjects judged whether the second sound of a three sound sequence was spatially closer to the first or the third sound. The tactile-feedback group underwent two audio-tactile feedback sessions of 100 trials, where each auditory trial was followed by the same spatial sequence played on the subject’s forearm; auditory spatial bisection thresholds were evaluated after each session. In the verbal-feedback condition, the positions of the sounds were verbally reported to the subject after each feedback trial. The no-feedback group did the same sequence of trials, with no feedback. Performance improved significantly only after audio-tactile feedback. The results suggest that direct tactile feedback interacts with the auditory spatial localization system, possibly by a process of cross-sensory recalibration. Control tests with the subject rotated suggested that this effect occurs only when the tactile and acoustic sequences are spatially coherent. Our results suggest that the tactile system can be used to recalibrate the auditory sense of space. These results encourage the possibility of designing rehabilitation programs to help blind persons establish a robust auditory sense of space, through training with the tactile modality.

  12. THE EFFECTS OF SALICYLATE ON AUDITORY EVOKED POTENTIAL AMPLITWDE FROM THE AUDITORY CORTEX AND AUDITORY BRAINSTEM

    Institute of Scientific and Technical Information of China (English)

    Brian Sawka; SUN Wei

    2014-01-01

    Tinnitus has often been studied using salicylate in animal models as they are capable of inducing tempo-rary hearing loss and tinnitus. Studies have recently observed enhancement of auditory evoked responses of the auditory cortex (AC) post salicylate treatment which is also shown to be related to tinnitus like behavior in rats. The aim of this study was to observe if enhancements of the AC post salicylate treatment are also present at structures in the brainstem. Four male Sprague Dawley rats with AC implanted electrodes were tested for both AC and auditory brainstem response (ABR) recordings pre and post 250 mg/kg intraperitone-al injections of salicylate. The responses were recorded as the peak to trough amplitudes of P1-N1 (AC), ABR wave V, and ABR waveⅡ. AC responses resulted in statistically significant enhancement of ampli-tude at 2 hours post salicylate with 90 dB stimuli tone bursts of 4, 8, 12, and 20 kHz. Wave V of ABR re-sponses at 90 dB resulted in a statistically significant reduction of amplitude 2 hours post salicylate and a mean decrease of amplitude of 31%for 16 kHz. WaveⅡamplitudes at 2 hours post treatment were signifi-cantly reduced for 4, 12, and 20 kHz stimuli at 90 dB SPL. Our results suggest that the enhancement chang-es of the AC related to salicylate induced tinnitus are generated superior to the level of the inferior colliculus and may originate in the AC.

  13. 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. PMID:21413843

  14. Basic Auditory Processing Deficits in Dyslexia: Systematic Review of the Behavioral and Event-Related Potential/Field Evidence

    Science.gov (United States)

    Hämäläinen, Jarmo A.; Salminen, Hanne K.; Leppänen, Paavo H. T.

    2013-01-01

    A review of research that uses behavioral, electroencephalographic, and/or magnetoencephalographic methods to investigate auditory processing deficits in individuals with dyslexia is presented. Findings show that measures of frequency, rise time, and duration discrimination as well as amplitude modulation and frequency modulation detection were…

  15. GRK5 Deficiency Leads to Selective Basal Forebrain Cholinergic Neuronal Vulnerability

    Science.gov (United States)

    He, Minchao; Singh, Prabhakar; Cheng, Shaowu; Zhang, Qiang; Peng, Wei; Ding, XueFeng; Li, Longxuan; Liu, Jun; Premont, Richard T.; Morgan, Dave; Burns, Jeffery M.; Swerdlow, Russell H.; Suo, William Z.

    2016-01-01

    Why certain diseases primarily affect one specific neuronal subtype rather than another is a puzzle whose solution underlies the development of specific therapies. Selective basal forebrain cholinergic (BFC) neurodegeneration participates in cognitive impairment in Alzheimer’s disease (AD), yet the underlying mechanism remains elusive. Here, we report the first recapitulation of the selective BFC neuronal loss that is typical of human AD in a mouse model termed GAP. We created GAP mice by crossing Tg2576 mice that over-express the Swedish mutant human β-amyloid precursor protein gene with G protein-coupled receptor kinase-5 (GRK5) knockout mice. This doubly defective mouse displayed significant BFC neuronal loss at 18 months of age, which was not observed in either of the singly defective parent strains or in the wild type. Along with other supporting evidence, we propose that GRK5 deficiency selectively renders BFC neurons more vulnerable to degeneration. PMID:27193825

  16. Adolescent Intermittent Alcohol Exposure: Deficits in Object Recognition Memory and Forebrain Cholinergic Markers.

    Directory of Open Access Journals (Sweden)

    H Scott Swartzwelder

    Full Text Available The long-term effects of intermittent ethanol exposure during adolescence (AIE are of intensive interest and investigation. The effects of AIE on learning and memory and the neural functions that drive them are of particular interest as clinical findings suggest enduring deficits in those cognitive domains in humans after ethanol abuse during adolescence. Although studies of such deficits after AIE hold much promise for identifying mechanisms and therapeutic interventions, the findings are sparse and inconclusive. The present results identify a specific deficit in memory function after AIE and establish a possible neural mechanism of that deficit that may be of translational significance. Male rats (starting at PND-30 received exposure to AIE (5g/kg, i.g. or vehicle and were allowed to mature into adulthood. At PND-71, one group of animals was assessed using the spatial-temporal object recognition (stOR test to evaluate memory function. A separate group of animals was used to assess the density of cholinergic neurons in forebrain areas Ch1-4 using immunohistochemistry. AIE exposed animals manifested deficits in the temporal component of the stOR task relative to controls, and a significant decrease in the number of ChAT labeled neurons in forebrain areas Ch1-4. These findings add to the growing literature indicating long-lasting neural and behavioral effects of AIE that persist into adulthood and indicate that memory-related deficits after AIE depend upon the tasks employed, and possibly their degree of complexity. Finally, the parallel finding of diminished cholinergic neuron density suggests a possible mechanism underlying the effects of AIE on memory and hippocampal function as well as possible therapeutic or preventive strategies for AIE.

  17. Spontaneous release of acetylcholine and acetylhomocholine from mouse forebrain minces: cytoplasmic or vesicular origin

    International Nuclear Information System (INIS)

    The objective of this study was to determine the subcellular origin of cholinergic transmitter released spontaneously from mouse forebrain minces. To accomplish this objective, minces were pretreated in ionic media and then loaded with [14C]homocholine, an analog of choline, to form the false transmitter [14Cy]acetylhomocholine [( 14C]AHCh). The ratio of the false transmitter [14C]AHCh to the true transmitter ACh was then used as an index of cholinergic transmitter contents for both the cytoplasmic (S3) and vesicle-bound (P3) fractions. Three different pretreatment procedures were used to cause the following changes in S3 and P3 false to true transmitter ratios prior to spontaneous release: 1) a small increase in the S3 ratio of [14C]AHCh to acetylcholine (ACh) and a large increase in the P3 ratio of [14C] AHCh to ACh; 2) a decrease in the S3 ratio of [14C]AHCh to ACh and an increase in the P3 ratio of [14C]AHCh to ACh; 3) an increase in the P3 ratio of [14C]AHCh to ACh without affecting the S3 ratio of [14C]AHCh to ACh. The influence of each pretreatment on these subcellular ratios was then compared with its influence on the spontaneous release ratio of [14C]AHCh to ACh. In all 3 instances, the influence of pretreatment on the ratio of spontaneously released false and true cholinergic transmitters from minces coincided with the effect of pretreatment on the pre-release ratio of false to true transmitter in the S3 fraction. These results suggest that much of the cholinergic transmitter which is spontaneously released from mouse forebrain occurs from the cytoplasmic fraction

  18. A Comparison of Three Auditory Discrimination-Perception Tests

    Science.gov (United States)

    Koenke, Karl

    1978-01-01

    Comparisons were made between scores of 52 third graders on three measures of auditory discrimination: Wepman's Auditory Discrimination Test, the Goldman-Fristoe Woodcock (GFW) Test of Auditory Discrimination, and the Kimmell-Wahl Screening Test of Auditory Perception (STAP). (CL)

  19. Encoding voice fundamental frequency into vibrotactile frequency.

    Science.gov (United States)

    Rothenberg, M; Molitor, R D

    1979-10-01

    Measured in this study was the ability of eight hearing and five deaf subjects to identify the stress pattern in a short sentence from the variation in voice fundamental frequency (F0), when presented aurally (for hearing subjects) and when transformed into vibrotactile pulse frequency. Various transformations from F0 to pulse frequency were tested in an attempt to determine an optimum transformation, the amount of F0 information that could be transmitted, and what the limitations in the tactile channel might be. The results indicated that a one- or two-octave reduction of F0 vibrotactile frequency (transmitting every second or third glottal pulse) might result in a significant ability to discriminate the intonation patterns associated with moderate-to-strong patterns of sentence stress in English. However, accurate reception of the details of the intonation pattern may require a slower than normal pronounciation because of an apparent temporal indeterminacy of about 200 ms in the perception of variations in vibrotactile frequency. A performance deficit noted for the two prelingually, profoundly deaf subjects with marginally discriminable encodings offers some support for our previous hypothesis that there is a natural association between auditory pitch and perceived vibrotactile frequency. PMID:159917

  20. Mechanisms and streams for processing of “what” and “where” in auditory cortex

    OpenAIRE

    Rauschecker, Josef P; Tian, Biao

    2000-01-01

    The functional specialization and hierarchical organization of multiple areas in rhesus monkey auditory cortex were examined with various types of complex sounds. Neurons in the lateral belt areas of the superior temporal gyrus were tuned to the best center frequency and bandwidth of band-passed noise bursts. They were also selective for the rate and direction of linear frequency modulated sweeps. Many neurons showed a preference for a limited number of species-specifi...

  1. Auditory Connections and Functions of Prefrontal Cortex

    Directory of Open Access Journals (Sweden)

    BethanyPlakke

    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.

  2. Functional Neurochemistry of the Auditory System

    Directory of Open Access Journals (Sweden)

    Nourollah Agha Ebrahimi

    1993-03-01

    Full Text Available Functional Neurochemistry is one of the fields of studies in the auditory system which has had an outstanding development in the recent years. Many of the findings in the mentioned field had led not only the basic auditory researches but also the clinicians to new points of view in audiology.Here, we are aimed at discussing the latest investigations in the Functional Neurochemistry of the auditory system and have focused this review mainly on the researches which will arise flashes of hope for future clinical studies

  3. Auditory Neuropathy/Dyssynchrony in Biotinidase Deficiency

    Science.gov (United States)

    Yaghini, Omid

    2016-01-01

    Biotinidase deficiency is a disorder inherited autosomal recessively showing evidence of hearing loss and optic atrophy in addition to seizures, hypotonia, and ataxia. In the present study, a 2-year-old boy with Biotinidase deficiency is presented in which clinical symptoms have been reported with auditory neuropathy/auditory dyssynchrony (AN/AD). In this case, transient-evoked otoacoustic emissions showed bilaterally normal responses representing normal function of outer hair cells. In contrast, acoustic reflex test showed absent reflexes bilaterally, and visual reinforcement audiometry and auditory brainstem responses indicated severe to profound hearing loss in both ears. These results suggest AN/AD in patients with Biotinidase deficiency. PMID:27144235

  4. Functional Neurochemistry of the Auditory System

    OpenAIRE

    Nourollah Agha Ebrahimi

    1993-01-01

    Functional Neurochemistry is one of the fields of studies in the auditory system which has had an outstanding development in the recent years. Many of the findings in the mentioned field had led not only the basic auditory researches but also the clinicians to new points of view in audiology.Here, we are aimed at discussing the latest investigations in the Functional Neurochemistry of the auditory system and have focused this review mainly on the researches which will arise flashes of hope f...

  5. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    Directory of Open Access Journals (Sweden)

    Zahra Shahidipour

    2014-01-01

    Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

  6. Deep transcranial magnetic stimulation for the treatment of auditory hallucinations: a preliminary open-label study

    Directory of Open Access Journals (Sweden)

    Zangen Abraham

    2011-02-01

    Full Text Available Abstract Background Schizophrenia is a chronic and disabling disease that presents with delusions and hallucinations. Auditory hallucinations are usually expressed as voices speaking to or about the patient. Previous studies have examined the effect of repetitive transcranial magnetic stimulation (TMS over the temporoparietal cortex on auditory hallucinations in schizophrenic patients. Our aim was to explore the potential effect of deep TMS, using the H coil over the same brain region on auditory hallucinations. Patients and methods Eight schizophrenic patients with refractory auditory hallucinations were recruited, mainly from Beer Ya'akov Mental Health Institution (Tel Aviv university, Israel ambulatory clinics, as well as from other hospitals outpatient populations. Low-frequency deep TMS was applied for 10 min (600 pulses per session to the left temporoparietal cortex for either 10 or 20 sessions. Deep TMS was applied using Brainsway's H1 coil apparatus. Patients were evaluated using the Auditory Hallucinations Rating Scale (AHRS as well as the Scale for the Assessment of Positive Symptoms scores (SAPS, Clinical Global Impressions (CGI scale, and the Scale for Assessment of Negative Symptoms (SANS. Results This preliminary study demonstrated a significant improvement in AHRS score (an average reduction of 31.7% ± 32.2% and to a lesser extent improvement in SAPS results (an average reduction of 16.5% ± 20.3%. Conclusions In this study, we have demonstrated the potential of deep TMS treatment over the temporoparietal cortex as an add-on treatment for chronic auditory hallucinations in schizophrenic patients. Larger samples in a double-blind sham-controlled design are now being preformed to evaluate the effectiveness of deep TMS treatment for auditory hallucinations. Trial registration This trial is registered with clinicaltrials.gov (identifier: NCT00564096.

  7. Modulation of auditory cortex response to pitch variation following training with microtonal melodies.

    Science.gov (United States)

    Zatorre, Robert J; Delhommeau, Karine; Zarate, Jean Mary

    2012-01-01

    We tested changes in cortical functional response to auditory patterns in a configural learning paradigm. We trained 10 human listeners to discriminate micromelodies (consisting of smaller pitch intervals than normally used in Western music) and measured covariation in blood oxygenation signal to increasing pitch interval size in order to dissociate global changes in activity from those specifically associated with the stimulus feature that was trained. A psychophysical staircase procedure with feedback was used for training over a 2-week period. Behavioral tests of discrimination ability performed before and after training showed significant learning on the trained stimuli, and generalization to other frequencies and tasks; no learning occurred in an untrained control group. Before training the functional MRI data showed the expected systematic increase in activity in auditory cortices as a function of increasing micromelody pitch interval size. This function became shallower after training, with the maximal change observed in the right posterior auditory cortex. Global decreases in activity in auditory regions, along with global increases in frontal cortices also occurred after training. Individual variation in learning rate was related to the hemodynamic slope to pitch interval size, such that those who had a higher sensitivity to pitch interval variation prior to learning achieved the fastest learning. We conclude that configural auditory learning entails modulation in the response of auditory cortex to the trained stimulus feature. Reduction in blood oxygenation response to increasing pitch interval size suggests that fewer computational resources, and hence lower neural recruitment, is associated with learning, in accord with models of auditory cortex function, and with data from other modalities. PMID:23227019

  8. Modulation of auditory cortex response to pitch variation following training with microtonal melodies

    Directory of Open Access Journals (Sweden)

    Robert J Zatorre

    2012-12-01

    Full Text Available We tested changes in cortical functional response to auditory configural learning by training ten human listeners to discriminate micromelodies (consisting of smaller pitch intervals than normally used in Western music. We measured covariation in blood oxygenation signal to increasing pitch-interval size in order to dissociate global changes in activity from those specifically associated with the stimulus feature of interest. A psychophysical staircase procedure with feedback was used for training over a two-week period. Behavioral tests of discrimination ability performed before and after training showed significant learning on the trained stimuli, and generalization to other frequencies and tasks; no learning occurred in an untrained control group. Before training the functional MRI data showed the expected systematic increase in activity in auditory cortices as a function of increasing micromelody pitch-interval size. This function became shallower after training, with the maximal change observed in the right posterior auditory cortex. Global decreases in activity in auditory regions, along with global increases in frontal cortices also occurred after training. Individual variation in learning rate was related to the hemodynamic slope to pitch-interval size, such that those who had a higher sensitivity to pitch-interval variation prior to learning achieved the fastest learning. We conclude that configural auditory learning entails modulation in the response of auditory cortex specifically to the trained stimulus feature. Reduction in blood oxygenation response to increasing pitch-interval size suggests that fewer computational resources, and hence lower neural recruitment, is associated with learning, in accord with models of auditory cortex function, and with data from other modalities.

  9. Deficit of auditory temporal processing in children with dyslexia-dysgraphia

    Directory of Open Access Journals (Sweden)

    Sima Tajik

    2012-12-01

    Full Text Available Background and Aim: Auditory temporal processing reveals an important aspect of auditory performance, in which a deficit can prevent the child from speaking, language learning and reading. Temporal resolution, which is a subgroup of temporal processing, can be evaluated by gap-in-noise detection test. Regarding the relation of auditory temporal processing deficits and phonologic disorder of children with dyslexia-dysgraphia, the aim of this study was to evaluate these children with the gap-in-noise (GIN test.Methods: The gap-in-noise test was performed on 28 normal and 24 dyslexic-dysgraphic children, at the age of 11-12 years old. Mean approximate threshold and percent of corrected answers were compared between the groups.Results: The mean approximate threshold and percent of corrected answers of the right and left ear had no significant difference between the groups (p>0.05. The mean approximate threshold of children with dyslexia-dysgraphia (6.97 ms, SD=1.09 was significantly (p<0.001 more than that of the normal group (5.05 ms, SD=0.92. The mean related frequency of corrected answers (58.05, SD=4.98% was less than normal group (69.97, SD=7.16% (p<0.001.Conclusion: Abnormal temporal resolution was found in children with dyslexia-dysgraphia based on gap-in-noise test. While the brainstem and auditory cortex are responsible for auditory temporal processing, probably the structural and functional differences of these areas in normal and dyslexic-dysgraphic children lead to abnormal coding of auditory temporal information. As a result, auditory temporal processing is inevitable.

  10. Neural Representation of Concurrent Vowels in Macaque Primary Auditory Cortex123

    Science.gov (United States)

    Micheyl, Christophe; Steinschneider, Mitchell

    2016-01-01

    Abstract Successful speech perception in real-world environments requires that the auditory system segregate competing voices that overlap in frequency and time into separate streams. Vowels are major constituents of speech and are comprised of frequencies (harmonics) that are integer multiples of a common fundamental frequency (F0). The pitch and identity of a vowel are determined by its F0 and spectral envelope (formant structure), respectively. When two spectrally overlapping vowels differing in F0 are presented concurrently, they can be readily perceived as two separate “auditory objects” with pitches at their respective F0s. A difference in pitch between two simultaneous vowels provides a powerful cue for their segregation, which in turn, facilitates their individual identification. The neural mechanisms underlying the segregation of concurrent vowels based on pitch differences are poorly understood. Here, we examine neural population responses in macaque primary auditory cortex (A1) to single and double concurrent vowels (/a/ and /i/) that differ in F0 such that they are heard as two separate auditory objects with distinct pitches. We find that neural population responses in A1 can resolve, via a rate-place code, lower harmonics of both single and double concurrent vowels. Furthermore, we show that the formant structures, and hence the identities, of single vowels can be reliably recovered from the neural representation of double concurrent vowels. We conclude that A1 contains sufficient spectral information to enable concurrent vowel segregation and identification by downstream cortical areas.

  11. Physiological Measures of Auditory Function

    Science.gov (United States)

    Kollmeier, Birger; Riedel, Helmut; Mauermann, Manfred; Uppenkamp, Stefan

    When acoustic signals enter the ears, they pass several processing stages of various complexities before they will be perceived. The auditory pathway can be separated into structures dealing with sound transmission in air (i.e. the outer ear, ear canal, and the vibration of tympanic membrane), structures dealing with the transformation of sound pressure waves into mechanical vibrations of the inner ear fluids (i.e. the tympanic membrane, ossicular chain, and the oval window), structures carrying mechanical vibrations in the fluid-filled inner ear (i.e. the cochlea with basilar membrane, tectorial membrane, and hair cells), structures that transform mechanical oscillations into a neural code, and finally several stages of neural processing in the brain along the pathway from the brainstem to the cortex.

  12. Psychophysical and neural correlates of noised-induced tinnitus in animals: Intra- and inter-auditory and non-auditory brain structure studies.

    Science.gov (United States)

    Zhang, Jinsheng; Luo, Hao; Pace, Edward; Li, Liang; Liu, Bin

    2016-04-01

    Tinnitus, a ringing in the ear or head without an external sound source, is a prevalent health problem. It is often associated with a number of limbic-associated disorders such as anxiety, sleep disturbance, and emotional distress. Thus, to investigate tinnitus, it is important to consider both auditory and non-auditory brain structures. This paper summarizes the psychophysical, immunocytochemical and electrophysiological evidence found in rats or hamsters with behavioral evidence of tinnitus. Behaviorally, we tested for tinnitus using a conditioned suppression/avoidance paradigm, gap detection acoustic reflex behavioral paradigm, and our newly developed conditioned licking suppression paradigm. Our new tinnitus behavioral paradigm requires relatively short baseline training, examines frequency specification of tinnitus perception, and achieves sensitive tinnitus testing at an individual level. To test for tinnitus-related anxiety and cognitive impairment, we used the elevated plus maze and Morris water maze. Our results showed that not all animals with tinnitus demonstrate anxiety and cognitive impairment. Immunocytochemically, we found that animals with tinnitus manifested increased Fos-like immunoreactivity (FLI) in both auditory and non-auditory structures. The manner in which FLI appeared suggests that lower brainstem structures may be involved in acute tinnitus whereas the midbrain and cortex are involved in more chronic tinnitus. Meanwhile, animals with tinnitus also manifested increased FLI in non-auditory brain structures that are involved in autonomic reactions, stress, arousal and attention. Electrophysiologically, we found that rats with tinnitus developed increased spontaneous firing in the auditory cortex (AC) and amygdala (AMG), as well as intra- and inter-AC and AMG neurosynchrony, which demonstrate that tinnitus may be actively produced and maintained by the interactions between the AC and AMG. PMID:26299842

  13. Seeing the Song: Left Auditory Structures May Track Auditory-Visual Dynamic Alignment

    OpenAIRE

    Mossbridge, Julia A.; Grabowecky, Marcia; Suzuki, Satoru

    2013-01-01

    Auditory and visual signals generated by a single source tend to be temporally correlated, such as the synchronous sounds of footsteps and the limb movements of a walker. Continuous tracking and comparison of the dynamics of auditory-visual streams is thus useful for the perceptual binding of information arising from a common source. Although language-related mechanisms have been implicated in the tracking of speech-related auditory-visual signals (e.g., speech sounds and lip movements), it i...

  14. AUDITORY CORTICAL PLASTICITY: DOES IT PROVIDE EVIDENCE FOR COGNITIVE PROCESSING IN THE AUDITORY CORTEX?

    OpenAIRE

    Irvine, Dexter R. F.

    2007-01-01

    The past 20 years have seen substantial changes in our view of the nature of the processing carried out in auditory cortex. Some processing of a cognitive nature, previously attributed to higher order “association” areas, is now considered to take place in auditory cortex itself. One argument adduced in support of this view is the evidence indicating a remarkable degree of plasticity in the auditory cortex of adult animals. Such plasticity has been demonstrated in a wide range of paradigms, i...

  15. Spontaneous high-gamma band activity reflects functional organization of auditory cortex in the awake macaque.

    Science.gov (United States)

    Fukushima, Makoto; Saunders, Richard C; Leopold, David A; Mishkin, Mortimer; Averbeck, Bruno B

    2012-06-01

    In the absence of sensory stimuli, spontaneous activity in the brain has been shown to exhibit organization at multiple spatiotemporal scales. In the macaque auditory cortex, responses to acoustic stimuli are tonotopically organized within multiple, adjacent frequency maps aligned in a caudorostral direction on the supratemporal plane (STP) of the lateral sulcus. Here, we used chronic microelectrocorticography to investigate the correspondence between sensory maps and spontaneous neural fluctuations in the auditory cortex. We first mapped tonotopic organization across 96 electrodes spanning approximately two centimeters along the primary and higher auditory cortex. In separate sessions, we then observed that spontaneous activity at the same sites exhibited spatial covariation that reflected the tonotopic map of the STP. This observation demonstrates a close relationship between functional organization and spontaneous neural activity in the sensory cortex of the awake monkey. PMID:22681693

  16. Voiced-speech representation by an analog silicon model of the auditory periphery.

    Science.gov (United States)

    Liu, W; Andreou, A G; Goldstein, M H

    1992-01-01

    An analog CMOS integration of a model for the auditory periphery is presented. The model consists of middle ear, basilar membrane, and hair cell/synapse modules which are derived from neurophysiological studies. The circuit realization of each module is discussed, and experimental data of each module's response to sinusoidal excitation are given. The nonlinear speech processing capabilities of the system are demonstrated using the voiced syllable |ba|. The multichannel output of the silicon model corresponds to the time-varying instantaneous firing rates of auditory nerve fibers that have different characteristic frequencies. These outputs are similar to the physiologically obtained responses. The actual implementation uses subthreshold CMOS technology and analog continuous-time circuits, resulting in a real-time, micropower device with potential applications as a preprocessor of auditory stimuli. PMID:18276451

  17. Vibration-induced auditory-cortex activation in a congenitally deaf adult.

    Science.gov (United States)

    Levänen, S; Jousmäki, V; Hari, R

    1998-07-16

    Considerable changes take place in the number of cerebral neurons, synapses and axons during development, mainly as a result of competition between different neural activities [1-4]. Studies using animals suggest that when input from one sensory modality is deprived early in development, the affected neural structures have the potential to mediate functions for the remaining modalities [5-8]. We now show that similar potential exists in the human auditory system: vibrotactile stimuli, applied on the palm and fingers of a congenitally deaf adult, activated his auditory cortices. The recorded magnetoencephalographic (MEG) signals also indicated that the auditory cortices were able to discriminate between the applied 180 Hz and 250 Hz vibration frequencies. Our findings suggest that human cortical areas, normally subserving hearing, may process vibrotactile information in the congenitally deaf. PMID:9705933

  18. Changes in regional cerebral blood flow during auditory cognitive tasks

    International Nuclear Information System (INIS)

    In order to investigate the relation between auditory cognitive function and regional brain activation, we measured the changes in the regional cerebral blood flow (CBF) using positron emission tomography (PET) during the 'odd-ball' paradigm in ten normal healthy volunteers. The subjects underwent 3 tasks, twice for each, while the evoked potential was recorded. In these tasks, the auditory stimulus was a series of pure tones delivered every 1.5 sec binaurally at 75 dB from the earphones. Task A: the stimulus was a series of tones with 1000 Hz only, and the subject was instructed to only hear. Task B: the stimulus was a series of tones with 1000 Hz only, and the subject was instructed to push the button on detecting a tone. Task C: the stimulus was a series of pure tones delivered every 1.5 sec binaurally at 75 dB with a frequency of 1000 Hz (non-target) in 80% and 2000 Hz (target) in 20% at random, and the subject was instructed to push the button on detecting a target tone. The event related potential (P300) was observed in task C (Pz: 334.3±19.6 msec). At each task, the CBF was measured using PET with i.v. injection of 1.5 GBq of O-15 water. The changes in CBF associated with auditory cognition was evaluated by the difference between the CBF images in task C and B. Localized increase was observed in the anterior cingulate cortex (in all subjects), the bilateral associate auditory cortex, the prefrontal cortex and the parietal cortex. The latter three areas had a large individual variation in the location of foci. These results suggested the role of those cortical areas in auditory cognition. The anterior cingulate was most activated (15.0±2.24% of global CBF). This region was not activated in the condition of task B minus task A. The anterior cingulate is a part of Papez's circuit that is related to memory and other higher cortical function. These results suggested that this area may play an important role in cognition as well as in attention. (author)

  19. Differential coding of conspecific vocalizations in the ventral auditory cortical stream.

    Science.gov (United States)

    Fukushima, Makoto; Saunders, Richard C; Leopold, David A; Mishkin, Mortimer; Averbeck, Bruno B

    2014-03-26

    The mammalian auditory cortex integrates spectral and temporal acoustic features to support the perception of complex sounds, including conspecific vocalizations. Here we investigate coding of vocal stimuli in different subfields in macaque auditory cortex. We simultaneously measured auditory evoked potentials over a large swath of primary and higher order auditory cortex along the supratemporal plane in three animals chronically using high-density microelectrocorticographic arrays. To evaluate the capacity of neural activity to discriminate individual stimuli in these high-dimensional datasets, we applied a regularized multivariate classifier to evoked potentials to conspecific vocalizations. We found a gradual decrease in the level of overall classification performance along the caudal to rostral axis. Furthermore, the performance in the caudal sectors was similar across individual stimuli, whereas the performance in the rostral sectors significantly differed for different stimuli. Moreover, the information about vocalizations in the caudal sectors was similar to the information about synthetic stimuli that contained only the spectral or temporal features of the original vocalizations. In the rostral sectors, however, the classification for vocalizations was significantly better than that for the synthetic stimuli, suggesting that conjoined spectral and temporal features were necessary to explain differential coding of vocalizations in the rostral areas. We also found that this coding in the rostral sector was carried primarily in the theta frequency band of the response. These findings illustrate a progression in neural coding of conspecific vocalizations along the ventral auditory pathway. PMID:24672012

  20. Size and synchronization of auditory cortex promotes musical, literacy, and attentional skills in children.

    Science.gov (United States)

    Seither-Preisler, Annemarie; Parncutt, Richard; Schneider, Peter

    2014-08-13

    Playing a musical instrument is associated with numerous neural processes that continuously modify the human brain and may facilitate characteristic auditory skills. In a longitudinal study, we investigated the auditory and neural plasticity of musical learning in 111 young children (aged 7-9 y) as a function of the intensity of instrumental practice and musical aptitude. Because of the frequent co-occurrence of central auditory processing disorders and attentional deficits, we also tested 21 children with attention deficit (hyperactivity) disorder [AD(H)D]. Magnetic resonance imaging and magnetoencephalography revealed enlarged Heschl's gyri and enhanced right-left hemispheric synchronization of the primary evoked response (P1) to harmonic complex sounds in children who spent more time practicing a musical instrument. The anatomical characteristics were positively correlated with frequency discrimination, reading, and spelling skills. Conversely, AD(H)D children showed reduced volumes of Heschl's gyri and enhanced volumes of the plana temporalia that were associated with a distinct bilateral P1 asynchrony. This may indicate a risk for central auditory processing disorders that are often associated with attentional and literacy problems. The longitudinal comparisons revealed a very high stability of auditory cortex morphology and gray matter volumes, suggesting that the combined anatomical and functional parameters are neural markers of musicality and attention deficits. Educational and clinical implications are considered. PMID:25122894

  1. Positive and negative reinforcement activate human auditory cortex

    Directory of Open Access Journals (Sweden)

    Tina Weis

    2013-12-01

    Full Text Available Prior studies suggest that reward modulates neural activity in sensory cortices, but less is known about punishment. We used functional magnetic resonance imaging and an auditory discrimination task, where participants had to judge the duration of frequency modulated tones. In one session correct performance resulted in financial gains at the end of the trial, in a second session incorrect performance resulted in financial loss. Incorrect performance in the rewarded as well as correct performance in the punishment condition resulted in a neutral outcome. The size of gains and losses was either low or high (10 or 50 Euro cent depending on the direction of frequency modulation. We analyzed neural activity at the end of the trial, during reinforcement, and found increased neural activity in auditory cortex when gaining a financial reward as compared to gaining no reward and when avoiding financial loss as compared to receiving a financial loss. This was independent on the size of gains and losses. A similar pattern of neural activity for both gaining a reward and avoiding a loss was also seen in right middle temporal gyrus, bilateral insula and pre-supplemental motor area, here however neural activity was lower after correct responses compared to incorrect responses. To summarize, this study shows that the activation of sensory cortices, as previously shown for gaining a reward is also seen during avoiding a loss.

  2. Angiotensin type 1a receptors in the forebrain subfornical organ facilitate leptin-induced weight loss through brown adipose tissue thermogenesis

    Directory of Open Access Journals (Sweden)

    Colin N. Young

    2015-04-01

    Conclusions: These data identify a novel interaction between angiotensin-II and leptin in the control of BAT thermogenesis and body weight, and highlight a previously unrecognized role for the forebrain SFO in metabolic regulation.

  3. Auditory and speech processing and reading development in Chinese school children: behavioural and ERP evidence.

    Science.gov (United States)

    Meng, Xiangzhi; Sai, Xiaoguang; Wang, Cixin; Wang, Jue; Sha, Shuying; Zhou, Xiaolin

    2005-11-01

    By measuring behavioural performance and event-related potentials (ERPs) this study investigated the extent to which Chinese school children's reading development is influenced by their skills in auditory, speech, and temporal processing. In Experiment 1, 102 normal school children's performance in pure tone temporal order judgment, tone frequency discrimination, temporal interval discrimination and composite tone pattern discrimination was measured. Results showed that children's auditory processing skills correlated significantly with their reading fluency, phonological awareness, word naming latency, and the number of Chinese characters learned. Regression analyses found that tone temporal order judgment, temporal interval discrimination and composite tone pattern discrimination could account for 32% of variance in phonological awareness. Controlling for the effect of phonological awareness, auditory processing measures still contributed significantly to variance in reading fluency and character naming. In Experiment 2, mismatch negativities (MMN) in event-related brain potentials were recorded from dyslexic children and the matched normal children, while these children listened passively to Chinese syllables and auditory stimuli composed of pure tones. The two groups of children did not differ in MMN to stimuli deviated in pure tone frequency and Chinese lexical tones. But dyslexic children showed smaller MMN to stimuli deviated in initial consonants or vowels of Chinese syllables and to stimuli deviated in temporal information of composite tone patterns. These results suggested that Chinese dyslexic children have deficits in auditory temporal processing as well as in linguistic processing and that auditory and temporal processing is possibly as important to reading development of children in a logographic writing system as in an alphabetic system. PMID:16355749

  4. Neural entrainment to rhythmically-presented auditory, visual and audio-visual speech in children

    Directory of Open Access Journals (Sweden)

    Alan James Power

    2012-07-01

    Full Text Available Auditory cortical oscillations have been proposed to play an important role in speech perception. It is suggested that the brain may take temporal ‘samples’ of information from the speech stream at different rates, phase-resetting ongoing oscillations so that they are aligned with similar frequency bands in the input (‘phase locking’. Information from these frequency bands is then bound together for speech perception. To date, there are no explorations of neural phase-locking and entrainment to speech input in children. However, it is clear from studies of language acquisition that infants use both visual speech information and auditory speech information in learning. In order to study neural entrainment to speech in typically-developing children, we use a rhythmic entrainment paradigm (underlying 2 Hz or delta rate based on repetition of the syllable ba, presented in either the auditory modality alone, the visual modality alone, or as auditory-visual speech (via a talking head. To ensure attention to the task, children aged 13 years were asked to press a button as fast as possible when the ba stimulus violated the rhythm for each stream type. Rhythmic violation depended on delaying the occurrence of a ba in the isochronous stream. Neural entrainment was demonstrated for all stream types, and individual differences in standardized measures of language processing were related to auditory entrainment at the theta rate. Further, there was significant modulation of the preferred phase of auditory entrainment in the theta band when visual speech cues were present, indicating cross-modal phase resetting. The rhythmic entrainment paradigm developed here offers a method for exploring individual differences in oscillatory phase locking during development. In particular, a method for assessing neural entrainment and cross-modal phase resetting would be useful for exploring developmental learning difficulties thought to involve temporal sampling

  5. Modulatory Effects of Attention on Lateral Inhibition in the Human Auditory Cortex.

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    Alva Engell

    Full Text Available Reduced neural processing of a tone is observed when it is presented after a sound whose spectral range closely frames the frequency of the tone. This observation might be explained by the mechanism of lateral inhibition (LI due to inhibitory interneurons in the auditory system. So far, several characteristics of bottom up influences on LI have been identified, while the influence of top-down processes such as directed attention on LI has not been investigated. Hence, the study at hand aims at investigating the modulatory effects of focused attention on LI in the human auditory cortex. In the magnetoencephalograph, we present two types of masking sounds (white noise vs. withe noise passing through a notch filter centered at a specific frequency, followed by a test tone with a frequency corresponding to the center-frequency of the notch filter. Simultaneously, subjects were presented with visual input on a screen. To modulate the focus of attention, subjects were instructed to concentrate either on the auditory input or the visual stimuli. More specific, on one half of the trials, subjects were instructed to detect small deviations in loudness in the masking sounds while on the other half of the trials subjects were asked to detect target stimuli on the screen. The results revealed a reduction in neural activation due to LI, which was larger during auditory compared to visual focused attention. Attentional modulations of LI were observed in two post-N1m time intervals. These findings underline the robustness of reduced neural activation due to LI in the auditory cortex and point towards the important role of attention on the modulation of this mechanism in more evaluative processing stages.

  6. Multi-Scale Entrainment of Coupled Neuronal Oscillations in Primary Auditory Cortex.

    Science.gov (United States)

    O'Connell, M N; Barczak, A; Ross, D; McGinnis, T; Schroeder, C E; Lakatos, P

    2015-01-01

    Earlier studies demonstrate that when the frequency of rhythmic tone sequences or streams is task relevant, ongoing excitability fluctuations (oscillations) of neuronal ensembles in primary auditory cortex (A1) entrain to stimulation in a frequency dependent way that sharpens frequency tuning. The phase distribution across A1 neuronal ensembles at time points when attended stimuli are predicted to occur reflects the focus of attention along the spectral attribute of auditory stimuli. This study examined how neuronal activity is modulated if only the temporal features of rhythmic stimulus streams are relevant. We presented macaques with auditory clicks arranged in 33 Hz (gamma timescale) quintets, repeated at a 1.6 Hz (delta timescale) rate. Such multi-scale, hierarchically organized temporal structure is characteristic of vocalizations and other natural stimuli. Monkeys were required to detect and respond to deviations in the temporal pattern of gamma quintets. As expected, engagement in the auditory task resulted in the multi-scale entrainment of delta- and gamma-band neuronal oscillations across all of A1. Surprisingly, however, the phase-alignment, and thus, the physiological impact of entrainment differed across the tonotopic map in A1. In the region of 11-16 kHz representation, entrainment most often aligned high excitability oscillatory phases with task-relevant events in the input stream and thus resulted in response enhancement. In the remainder of the A1 sites, entrainment generally resulted in response suppression. Our data indicate that the suppressive effects were due to low excitability phase delta oscillatory entrainment and the phase amplitude coupling of delta and gamma oscillations. Regardless of the phase or frequency, entrainment appeared stronger in left A1, indicative of the hemispheric lateralization of auditory function. PMID:26696866

  7. Multi-scale entrainment of coupled neuronal oscillations in primary auditory cortex.

    Directory of Open Access Journals (Sweden)

    Monica Noelle O'Connell

    2015-12-01

    Full Text Available Earlier studies demonstrate that when the frequency of rhythmic tone sequences or streams is task relevant, ongoing excitability fluctuations (oscillations of neuronal ensembles in primary auditory cortex (A1 entrain to stimulation in a frequency dependent way that sharpens frequency tuning. The phase distribution across A1 neuronal ensembles at time points when attended stimuli are predicted to occur reflects the focus of attention along the spectral attribute of auditory stimuli. This study examined how neuronal activity is modulated if only the temporal features of rhythmic stimulus streams are relevant. We presented macaques with auditory clicks arranged in 33 Hz (gamma timescale quintets, repeated at a 1.6 Hz (delta timescale rate. Such multi-scale, hierarchically organized temporal structure is characteristic of vocalizations and other natural stimuli. Monkeys were required to detect and respond to deviations in the temporal pattern of gamma quintets. As expected, engagement in the auditory task resulted in the multi-scale entrainment of delta- and gamma-band neuronal oscillations across all of A1. Surprisingly, however, the phase-alignment, and thus, the physiological impact of entrainment differed across the tonotopic map in A1. In the region of 11-16 kHz representation, entrainment most often aligned high excitability oscillatory phases with task-relevant events in the input stream and thus resulted in response enhancement. In the remainder of the A1 sites, entrainment generally resulted in response suppression. Our data indicate that the suppressive effects were due to low excitability phase delta oscillatory entrainment and the phase amplitude coupling of delta and gamma oscillations. Regardless of the phase or frequency, entrainment appeared stronger in left A1, indicative of the hemispheric lateralization of auditory function.

  8. In search of an auditory engram

    Science.gov (United States)

    Fritz, Jonathan; Mishkin, Mortimer; Saunders, Richard C.

    2005-01-01

    Monkeys trained preoperatively on a task designed to assess auditory recognition memory were impaired after removal of either the rostral superior temporal gyrus or the medial temporal lobe but were unaffected by lesions of the rhinal cortex. Behavioral analysis indicated that this result occurred because the monkeys did not or could not use long-term auditory recognition, and so depended instead on short-term working memory, which is unaffected by rhinal lesions. The findings suggest that monkeys may be unable to place representations of auditory stimuli into a long-term store and thus question whether the monkey's cerebral memory mechanisms in audition are intrinsically different from those in other sensory modalities. Furthermore, it raises the possibility that language is unique to humans not only because it depends on speech but also because it requires long-term auditory memory. PMID:15967995

  9. Auditory stimulation and cardiac autonomic regulation

    Directory of Open Access Journals (Sweden)

    Vitor E. Valenti

    2012-08-01

    Full Text Available Previous studies have already demonstrated that auditory stimulation with music influences the cardiovascular system. In this study, we described the relationship between musical auditory stimulation and heart rate variability. Searches were performed with the Medline, SciELO, Lilacs and Cochrane databases using the following keywords: "auditory stimulation", "autonomic nervous system", "music" and "heart rate variability". The selected studies indicated that there is a strong correlation between noise intensity and vagal-sympathetic balance. Additionally, it was reported that music therapy improved heart rate variability in anthracycline-treated breast cancer patients. It was hypothesized that dopamine release in the striatal system induced by pleasurable songs is involved in cardiac autonomic regulation. Musical auditory stimulation influences heart rate variability through a neural mechanism that is not well understood. Further studies are necessary to develop new therapies to treat cardiovascular disorders.

  10. Environment for Auditory Research Facility (EAR)

    Data.gov (United States)

    Federal Laboratory Consortium — EAR is an auditory perception and communication research center enabling state-of-the-art simulation of various indoor and outdoor acoustic environments. The heart...

  11. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    ArjenAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  12. Effect of omega-3 on auditory system

    Directory of Open Access Journals (Sweden)

    Vida Rahimi

    2014-01-01

    Full Text Available Background and Aim: Omega-3 fatty acid have structural and biological roles in the body 's various systems . Numerous studies have tried to research about it. Auditory system is affected a s well. The aim of this article was to review the researches about the effect of omega-3 on auditory system.Methods: We searched Medline , Google Scholar, PubMed, Cochrane Library and SID search engines with the "auditory" and "omega-3" keywords and read textbooks about this subject between 19 70 and 20 13.Conclusion: Both excess and deficient amounts of dietary omega-3 fatty acid can cause harmful effects on fetal and infant growth and development of brain and central nervous system esspesially auditory system. It is important to determine the adequate dosage of omega-3.

  13. Corticofugal modulation of peripheral auditory responses

    OpenAIRE

    Terreros, Gonzalo; Delano, Paul H.

    2015-01-01

    The auditory efferent system originates in the auditory cortex and projects to the medial geniculate body (MGB), inferior colliculus (IC), cochlear nucleus (CN) and superior olivary complex (SOC) reaching the cochlea through olivocochlear (OC) fibers. This unique neuronal network is organized in several afferent-efferent feedback loops including: the (i) colliculo-thalamic-cortico-collicular; (ii) cortico-(collicular)-OC; and (iii) cortico-(collicular)-CN pathways. Recent experiments demonstr...

  14. Corticofugal modulation of peripheral auditory responses

    OpenAIRE

    Paul Hinckley Delano

    2015-01-01

    The auditory efferent system originates in the auditory cortex and projects to the medial geniculate body, inferior colliculus, cochlear nucleus and superior olivary complex reaching the cochlea through olivocochlear fibers. This unique neuronal network is organized in several afferent-efferent feedback loops including: the (i) colliculo-thalamic-cortico-collicular, (ii) cortico-(collicular)-olivocochlear and (iii) cortico-(collicular)-cochlear nucleus pathways. Recent experiments demonstrate...

  15. Auditory memory function in expert chess players

    OpenAIRE

    Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

    2015-01-01

    Background: Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert...

  16. Music perception, pitch, and the auditory system

    OpenAIRE

    McDermott, Josh H.; Oxenham, Andrew J.

    2008-01-01

    The perception of music depends on many culture-specific factors, but is also constrained by properties of the auditory system. This has been best characterized for those aspects of music that involve pitch. Pitch sequences are heard in terms of relative, as well as absolute, pitch. Pitch combinations give rise to emergent properties not present in the component notes. In this review we discuss the basic auditory mechanisms contributing to these and other perceptual effects in music.

  17. Auditory brain-stem responses in syphilis.

    OpenAIRE

    Rosenhall, U; Roupe, G

    1981-01-01

    Analysis of auditory brain-stem electrical responses (BSER) provides an effective means of detecting lesions in the auditory pathways. In the present study the wave patterns were analysed in 11 patients with secondary or latent syphilis with no clinical symptoms referrable to the central nervous system and in two patients with congenital syphilis and general paralysis. Decreased amplitudes and prolonged latencies occurred frequently in patients with secondary and with advanced syphilis. This ...

  18. Auditory sequence analysis and phonological skill

    OpenAIRE

    Grube, Manon; Kumar, Sukhbinder; Cooper, Freya E.; Turton, Stuart; Griffiths, Timothy D

    2012-01-01

    This work tests the relationship between auditory and phonological skill in a non-selected cohort of 238 school students (age 11) with the specific hypothesis that sound-sequence analysis would be more relevant to phonological skill than the analysis of basic, single sounds. Auditory processing was assessed across the domains of pitch, time and timbre; a combination of six standard tests of literacy and language ability was used to assess phonological skill. A significant correlation between ...

  19. Kv2.2: A Novel Molecular Target to Study the Role of Basal Forebrain GABAergic Neurons in the Sleep-Wake Cycle

    Science.gov (United States)

    Hermanstyne, Tracey O.; Subedi, Kalpana; Le, Wei Wei; Hoffman, Gloria E.; Meredith, Andrea L.; Mong, Jessica A.; Misonou, Hiroaki

    2013-01-01

    Study Objectives: The basal forebrain (BF) has been implicated as an important brain region that regulates the sleep-wake cycle of animals. Gamma-aminobutyric acidergic (GABAergic) neurons are the most predominant neuronal population within this region. However, due to the lack of specific molecular tools, the roles of the BF GABAergic neurons have not been fully elucidated. Previously, we have found high expression levels of the Kv2.2 voltage-gated potassium channel on approximately 60% of GABAergic neurons in the magnocellular preoptic area and horizontal limb of the diagonal band of Broca of the BF and therefore proposed it as a potential molecular target to study this neuronal population. In this study, we sought to determine the functional roles of the Kv2.2-expressing neurons in the regulation of the sleep-wake cycle. Design: Sleep analysis between two genotypes and within each genotype before and after sleep deprivation. Setting: Animal sleep research laboratory. Participants: Adult mice. Wild-type and Kv2.2 knockout mice with C57/BL6 background. Interventions: EEG/EMG recordings from the basal state and after sleep-deprivation which was induced by mild aggitation for 6 h. Results: Immunostaining of a marker of neuronal activity indicates that these Kv2.2-expressing neurons appear to be preferentially active during the wake state. Therefore, we tested whether Kv2.2-expressing neurons in the BF are involved in arousal using Kv2.2-deficient mice. BF GABAergic neurons exhibited augmented expression of c-Fos. These knockout mice exhibited longer consolidated wake bouts than wild-type littermates, and that phenotype was further exacerbated by sleep deprivation. Moreover, in-depth analyses of their cortical electroencephalogram revealed a significant decrease in the delta-frequency activity during the nonrapid eye movement sleep state. Conclusions: These results revealed the significance of Kv2.2-expressing neurons in the regulation of the sleep-wake cycle

  20. Speech Evoked Auditory Brainstem Response in Stuttering

    Directory of Open Access Journals (Sweden)

    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.

  1. Analysis of heart rate variability during auditory stimulation periods in patients with schizophrenia.

    Science.gov (United States)

    Akar, Saime Akdemir; Kara, Sadık; Latifoğlu, Fatma; Bilgiç, Vedat

    2015-02-01

    The vulnerability-stress model is a hypothesis for symptom development in schizophrenia patients who are generally characterized by cardiac autonomic dysfunction. Therefore, measures of heart rate variability (HRV) have been widely used in schizophrenics for assessing altered cardiac autonomic regulations. The goal of this study was to analyze HRV of schizophrenia patients and healthy control subjects with exposure to auditory stimuli. More specifically, this study examines whether schizophrenia patients may exhibit distinctive time and frequency domain parameters of HRV from control subjects during at rest and auditory stimulation periods. Photoplethysmographic signals were used in the analysis of HRV. Nineteen schizophrenic patients and twenty healthy control subjects were examined during rest periods, while exposed to periods of white noise (WN) and relaxing music. Results indicate that HRV in patients was lower than that of control subjects indicating autonomic dysfunction throughout the entire experiment. In comparison with control subjects, patients with schizophrenia exhibited lower high-frequency power and a higher low-frequency to high-frequency ratio. Moreover, while WN stimulus decreased parasympathetic activity in healthy subjects, no significant changes in heart rate and frequency-domain HRV parameters were observed between the auditory stimulation and rest periods in schizophrenia patients. We can conclude that HRV can be used as a sensitive index of emotion-related sympathetic activity in schizophrenia patients. PMID:24831932

  2. Deletion of glycine transporter 1 (GlyT1) in forebrain neurons facilitates reversal learning: Enhanced cognitive adaptability?

    OpenAIRE

    Singer, Philipp; Boison, Detlev; Möhler, Hanns; FELDON, JORAM; Yee, Benjamin K.

    2009-01-01

    Local availability of glycine near N-methyl-d-aspartate receptors (NMDARs) is partly regulated by neuronal glycine transporter 1 (GlyT1), which can therefore modulate NMDAR function because binding to the glycine site of the NMDAR is necessary for channel activation. Disrupting GlyT1 in forebrain neurons has been shown to enhance Pavlovian conditioning and object recognition memory. Here, we reported that the same genetic manipulation facilitated reversal learning in the water maze test of re...

  3. Long-lasting novelty-induced neuronal reverberation during slow-wave sleep in multiple forebrain areas.

    OpenAIRE

    Ribeiro Sidarta; Gervasoni Damien; Soares Ernesto S; Zhou Yi; Lin Shih-Chieh; Pantoja Janaina; Lavine Michael; Nicolelis Miguel A. L

    2004-01-01

    The discovery of experience-dependent brain reactivation during both slow-wave (SW) and rapid eye-movement (REM) sleep led to the notion that the consolidation of recently acquired memory traces requires neural replay during sleep. To date, however, several observations continue to undermine this hypothesis. To address some of these objections, we investigated the effects of a transient novel experience on the long-term evolution of ongoing neuronal activity in the rat forebrain. We observed ...

  4. ESC-Derived Basal Forebrain Cholinergic Neurons Ameliorate the Cognitive Symptoms Associated with Alzheimer’s Disease in Mouse Models

    Directory of Open Access Journals (Sweden)

    Wei Yue

    2015-11-01

    Full Text Available Degeneration of basal forebrain cholinergic neurons (BFCNs is associated with cognitive impairments of Alzheimer’s disease (AD, implying that BFCNs hold potentials in exploring stem cell-based replacement therapy for AD. However, studies on derivation of BFCNs from embryonic stem cells (ESCs are limited, and the application of ESC-derived BFCNs remains to be determined. Here, we report on differentiation approaches for directing both mouse and human ESCs into mature BFCNs. These ESC-derived BFCNs exhibit features similar to those of their in vivo counterparts and acquire appropriate functional properties. After transplantation into the basal forebrain of AD model mice, ESC-derived BFCN progenitors predominantly differentiate into mature cholinergic neurons that functionally integrate into the endogenous basal forebrain cholinergic projection system. The AD mice grafted with mouse or human BFCNs exhibit improvements in learning and memory performances. Our findings suggest a promising perspective of ESC-derived BFCNs in the development of stem cell-based therapies for treatment of AD.

  5. Astaxanthin limits fish oil-related oxidative insult in the anterior forebrain of Wistar rats: putative anxiolytic effects?

    Science.gov (United States)

    Mattei, Rita; Polotow, Tatiana G; Vardaris, Cristina V; Guerra, Beatriz A; Leite, José Roberto; Otton, Rosemari; Barros, Marcelo P

    2011-09-01

    The habitual consumption of marine fish is largely associated to human mental health. Fish oil is particularly rich in n-3 polyunsaturated fatty acids that are known to play a role in several neuronal and cognitive functions. In parallel, the orange-pinkish carotenoid astaxanthin (ASTA) is found in salmon and displays important antioxidant and anti-inflammatory properties. Many neuronal dysfunctions and anomalous psychotic behavior (such as anxiety, depression, etc.) have been strongly related to the higher sensitivity of cathecolaminergic brain regions to oxidative stress. Thus, the aim of this work was to study the combined effect of ASTA and fish oil on the redox status in plasma and in the monoaminergic-rich anterior forebrain region of Wistar rats with possible correlations with the anxiolytic behavior. Upon fish oil supplementation, the downregulation of superoxide dismutase and catalase activities combined to increased "free" iron content resulted in higher levels of lipid and protein oxidation in the anterior forebrain of animals. Such harmful oxidative modifications were hindered by concomitant supplementation with ASTA despite ASTA-related antioxidant protection was mainly observed in plasma. Although it is clear that ASTA properly crosses the brain-blood barrier, our data also address a possible indirect role of ASTA in restoring basal oxidative conditions in anterior forebrain of animals: by improving GSH-based antioxidant capacity of plasma. Preliminary anxiolytic tests performed in the elevated plus maze are in alignment with our biochemical observations. PMID:21619892

  6. Asymmetric transfer of auditory perceptual learning

    Directory of Open Access Journals (Sweden)

    SygalAmitay

    2012-11-01

    Full Text Available Perceptual skills can improve dramatically even with minimal practice. A major and practical benefit of learning, however, is in transferring the improvement on the trained task to untrained tasks or stimuli, yet the mechanisms underlying this process are still poorly understood. Reduction of internal noise has been proposed as a mechanism of perceptual learning, and while we have evidence that frequency discrimination (FD learning is due to a reduction of internal noise, the source of that noise was not determined. In this study, we examined whether reducing the noise associated with neural phase locking to tones can explain the observed improvement in behavioural thresholds. We compared FD training between two tone durations (15 and 100 ms that straddled the temporal integration window of auditory nerve fibers upon which computational modeling of phase locking noise was based. Training on short tones resulted in improved FD on probe tests of both the long and short tones. Training on long tones resulted in improvement only on the long tones. Simulations of FD learning, based on the computational model and on signal detection theory, were compared with the behavioral FD data. We found that improved fidelity of phase locking accurately predicted transfer of learning from short to long tones, but also predicted transfer from long to short tones. The observed lack of transfer from long to short tones suggests the involvement of a second mechanism. Training may have increased the temporal integration window which could not transfer because integration time for the short tone is limited by its duration. Current learning models assume complex relationships between neural populations that represent the trained stimuli. In contrast, we propose that training-induced enhancement of the signal-to-noise ratio offers a parsimonious explanation of learning and transfer that easily accounts for asymmetric transfer of learning.

  7. Music-induced cortical plasticity and lateral inhibition in the human auditory cortex as foundations for tonal tinnitus treatment

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    Christo Pantev

    2012-06-01

    Full Text Available Over the past 15 years, we have studied plasticity in the human auditory cortex by means of magnetoencephalography (MEG. Two main topics nurtured our curiosity: the effects of musical training on plasticity in the auditory system, and the effects of lateral inhibition. One of our plasticity studies found that listening to notched music for three hours inhibited the neuronal activity in the auditory cortex that corresponded to the center-frequency of the notch, suggesting suppression of neural activity by lateral inhibition. Crucially, the overall effects of lateral inhibition on human auditory cortical activity were stronger than the habituation effects. Based on these results we developed a novel treatment strategy for tonal tinnitus - tailor-made notched music training (TMNMT. By notching the music energy spectrum around the individual tinnitus frequency, we intended to attract lateral inhibition to auditory neurons involved in tinnitus perception. So far, the training strategy has been evaluated in two studies. The results of the initial long-term controlled study (12 months supported the validity of the treatment concept: subjective tinnitus loudness and annoyance were significantly reduced after TMNMT but not when notching spared the tinnitus frequencies. Correspondingly, tinnitus-related auditory evoked fields (AEFs were significantly reduced after training. The subsequent short-term (5 days training study indicated that training was more effective in the case of tinnitus frequencies ≤ 8 kHz compared to tinnitus frequencies > 8 kHz, and that training should be employed over a long-term in order to induce more persistent effects. Further development and evaluation of TMNMT therapy are planned. A goal is to transfer this novel, completely non-invasive, and low-cost treatment approach for tonal tinnitus into routine clinical practice.

  8. Compensation of F0 and formant frequencies in a real-time pitch-perturbation paradigm

    DEFF Research Database (Denmark)

    Eckey, Andreas; MacDonald, Ewen

    2015-01-01

    While producing speech, talkers monitor both somatosensory and auditory feedback. Many studies have demonstrated that if auditory feedback is manipulated in real-time (e.g., using an effects processor to shift the frequency spectrum), subjects compensate by modifying their F0 in the direction opp...

  9. Improvement of auditory hallucinations and reduction of primary auditory area's activation following TMS

    International Nuclear Information System (INIS)

    Background: In the present case study, improvement of auditory hallucinations following transcranial magnetic stimulation (TMS) therapy was investigated with respect to activation changes of the auditory cortices. Methods: Using functional magnetic resonance imaging (fMRI), activation of the auditory cortices was assessed prior to and after a 4-week TMS series of the left superior temporal gyrus in a schizophrenic patient with medication-resistant auditory hallucinations. Results: Hallucinations decreased slightly after the third and profoundly after the fourth week of TMS. Activation in the primary auditory area decreased, whereas activation in the operculum and insula remained stable. Conclusions: Combination of TMS and repetitive fMRI is promising to elucidate the physiological changes induced by TMS.

  10. External auditory canal carcinoma treatment

    International Nuclear Information System (INIS)

    External auditory canal (EAC) carcinomas are relatively rare conditions lack on established treatment strategy. We analyzed a treatment modalities and outcome in 32 cases of EAC squamous cell carcinoma treated between 1980 and 2008. Subjects-17 men and 15 women ranging from 33 to 92 years old (average: 66) were divided by Arriaga's tumor staging into 12 T1, 5 T2, 6 T3, and 9 T4. Survival was calculated by the Kaplan-Meier method. Disease-specific 5-year survival was 100% for T1, T2, 44% for T3, and 33% for T4. In contrast to 100% 5-year survival for T1+T2 cancer, the 5-year survival for T3+T4 cancer was 37% with high recurrence due to positive surgical margins. The first 22 years of the 29 years surveyed, we performed surgery mainly, and irradiation or chemotherapy was selected for early disease or cases with positive surgical margins as postoperative therapy. During the 22-years, 5-year survival with T3+T4 cancer was 20%. After we started superselective intra-arterial (IA) rapid infusion chemotherapy combined with radiotherapy in 2003, we achieved negative surgical margins for advanced disease, and 5-year survival for T3+T4 cancer rise to 80%. (author)

  11. Automatic teleaudiometry: a low cost method to auditory screening

    Directory of Open Access Journals (Sweden)

    Campelo, Victor Eulálio Sousa

    2010-03-01

    Full Text Available Introduction: The auditory screening' benefits has been demonstrated, however these programs has been restricted to the big centers. Objectives: (a Developing a auditory screening method to distance; (b Testing its accuracy and comparing to the screening audiometry test (AV. Method: The teleaudiometry (TA, consists in a developed software, installed in a computer with phone TDH39. It was realized a study in series in 73 individuals between 17 and 50 years, being 57,%% of the female sex, they were randomly selected between patients and companions of the Hospital das Clínicas. Before were subjected to a symptom questionnaire and otoscopy, the individuals realized the tests of TA AV, with scanning in 20dB in the frequencies of 1,2 and 4kHz following the ASHA (1997 protocol and to the gold standard test of audiometry of pure tones in soundproof booth in aleatory order. Results: the TA has lasted average 125+11s and the AV 65+18s. 69 individuals (94,5% declaring to be found difficult or very easy to performing the TA and 61 (83,6% have considered easy or very easy the AV. The accuracy results of TA and AV were respectively: sensibility (86,7% / 86,7%, specificity (75,9%/ 72,4% and negative predictive value (95,7% / 95,5%, positive predictive value (48,1% / 55,2%. Conclusion: The teleaudiometry has showed a good option as an auditory screening method, presenting accuracy next to screening audiometry. In comparison with this method, the teleaudiometry has presented a similar sensibility, major specificity, negative predictive value and endurance time and, under positive predictive value.

  12. Basal forebrain motivational salience signal enhances cortical processing and decision speed

    Directory of Open Access Journals (Sweden)

    Sylvina M Raver

    2015-10-01

    Full Text Available The basal forebrain (BF contains major projections to the cerebral cortex, and plays a well-documented role in arousal, attention, decision-making, and in modulating cortical activity. BF neuronal degeneration is an early event in Alzheimer’s disease and dementias, and occurs in normal cognitive aging. While the BF is best known for its population of cortically projecting cholinergic neurons, the region is anatomically and neurochemically diverse, and also contains prominent populations of non-cholinergic projection neurons. In recent years, increasing attention has been dedicated to these non-cholinergic BF neurons in order to better understand how non-cholinergic BF circuits control cortical processing and behavioral performance. In this review, we focus on a unique population of putative non-cholinergic BF neurons that encodes the motivational salience of stimuli with a robust ensemble bursting response. We review recent studies that describe the specific physiological and functional characteristics of these BF salience-encoding neurons in behaving animals. These studies support the unifying hypothesis whereby BF salience-encoding neurons act as a gain modulation mechanism of the decision-making process to enhance cortical processing of behaviorally relevant stimuli, and thereby facilitate faster and more precise behavioral responses. This function of BF salience-encoding neurons represents a critical component in determining which incoming stimuli warrant an animal’s attention, and is therefore a fundamental and early requirement of behavioral flexibility.

  13. NKCC1 controls GABAergic signaling and neuroblast migration in the postnatal forebrain

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    Murray Kerren

    2011-02-01

    Full Text Available Abstract From an early postnatal period and throughout life there is a continuous production of olfactory bulb (OB interneurons originating from neuronal precursors in the subventricular zone. To reach the OB circuits, immature neuroblasts migrate along the rostral migratory stream (RMS. In the present study, we employed cultured postnatal mouse forebrain slices and used lentiviral vectors to label neuronal precursors with GFP and to manipulate the expression levels of the Na-K-2Cl cotransporter NKCC1. We investigated the role of this Cl- transporter in different stages of postnatal neurogenesis, including neuroblast migration and integration in the OB networks once they have reached the granule cell layer (GCL. We report that NKCC1 activity is necessary for maintaining normal migratory speed. Both pharmacological and genetic manipulations revealed that NKCC1 maintains high [Cl-]i and regulates the resting membrane potential of migratory neuroblasts whilst its functional expression is strongly reduced at the time cells reach the GCL. As in other developing systems, NKCC1 shapes GABAA-dependent signaling in the RMS neuroblasts. Also, we show that NKCC1 controls the migration of neuroblasts in the RMS. The present study indeed indicates that the latter effect results from a novel action of NKCC1 on the resting membrane potential, which is independent of GABAA-dependent signaling. All in all, our findings show that early stages of the postnatal recruitment of OB interneurons rely on precise, orchestrated mechanisms that depend on multiple actions of NKCC1.

  14. Antagonist of the amylin receptor blocks beta-amyloid toxicity in rat cholinergic basal forebrain neurons.

    Science.gov (United States)

    Jhamandas, Jack H; MacTavish, David

    2004-06-16

    Salvage of cholinergic neurons in the brain through a blockade of the neurotoxic effects of amyloidbeta protein (Abeta) is one of the major, but still elusive, therapeutic goals of current research in Alzheimer's disease (AD). To date, no receptor has been unequivocally identified for Abeta. Human amylin, which acts via a receptor composed of the calcitonin receptor-like receptor and a receptor-associated membrane protein, possesses amyloidogenic properties and has a profile of neurotoxicity that is strikingly similar to Abeta. In this study, using primary cultures of rat cholinergic basal forebrain neurons, we show that acetyl-[Asn30, Tyr32] sCT(8-37) (AC187), an amylin receptor antagonist, blocks Abeta-induced neurotoxicity. Treatment of cultures with AC187 before exposure to Abeta results in significantly improved neuronal survival as judged by MTT and live-dead cell assays. Quantitative measures of Abeta-evoked apoptotic cell death, using Hoechst and phosphotidylserine staining, confirm neuroprotective effects of AC187. We also demonstrate that AC187 attenuates the activation of initiator and effector caspases that mediate Abeta-induced apoptotic cell death. These data are the first to show that expression of Abeta toxicity may occur through the amylin receptor and suggest a novel therapeutic target for the treatment of AD. PMID:15201330

  15. Large-Scale Network Organisation in the Avian Forebrain: A Connectivity Matrix and Theoretical Analysis

    Directory of Open Access Journals (Sweden)

    Murray eShanahan

    2013-07-01

    Full Text Available Many species of birds, including pigeons, possess demonstrable cognitive capacities, and some are capable of cognitive feats matching those of apes. Since mammalian cortex is laminar while the avian telencephalon is nucleated, it is natural to ask whether the brains of these two cognitively capable taxa, despite their apparent anatomical dissimilarities, might exhibit common principles of organisation on some level. Complementing recent investigations of macro-scale brain connectivity in mammals, including humans and macaques, we here present the first large-scale wiring diagram for the forebrain of a bird. Using graph theory, we show that the pigeon telencephalon is organised along similar lines to that of a mammal. Both are modular, small-world networks with a connective core of hub nodes that includes prefrontal-like and hippocampal structures. These hub nodes are, topologically speaking, the most central regions of the pigeon's brain, as well as being the most richly connected, implying a crucial role in information flow. Overall, our analysis suggests that indeed, despite the absence of cortical layers and close to 300 million years of separate evolution, the connectivity of the avian brain conforms to the same organisational principles as the mammalian brain.

  16. Birds have primate-like numbers of neurons in the forebrain.

    Science.gov (United States)

    Olkowicz, Seweryn; Kocourek, Martin; Lučan, Radek K; Porteš, Michal; Fitch, W Tecumseh; Herculano-Houzel, Suzana; Němec, Pavel

    2016-06-28

    Some birds achieve primate-like levels of cognition, even though their brains tend to be much smaller in absolute size. This poses a fundamental problem in comparative and computational neuroscience, because small brains are expected to have a lower information-processing capacity. Using the isotropic fractionator to determine numbers of neurons in specific brain regions, here we show that the brains of parrots and songbirds contain on average twice as many neurons as primate brains of the same mass, indicating that avian brains have higher neuron packing densities than mammalian brains. Additionally, corvids and parrots have much higher proportions of brain neurons located in the pallial telencephalon compared with primates or other mammals and birds. Thus, large-brained parrots and corvids have forebrain neuron counts equal to or greater than primates with much larger brains. We suggest that the large numbers of neurons concentrated in high densities in the telencephalon substantially contribute to the neural basis of avian intelligence. PMID:27298365

  17. Differential vascular permeability along the forebrain ventricular neurogenic niche in the adult murine brain.

    Science.gov (United States)

    Colín-Castelán, Dannia; Ramírez-Santos, Jesús; Gutiérrez-Ospina, Gabriel

    2016-02-01

    Adult neurogenesis is influenced by blood-borne factors. In this context, greater or lesser vascular permeability along neurogenic niches would expose differentially neural stem cells (NSCs), transit amplifying cells (TACs), and neuroblasts to such factors. Here we evaluate endothelial cell morphology and vascular permeability along the forebrain neurogenic niche in the adult brain. Our results confirm that the subventricular zone (SVZ) contains highly permeable, discontinuous blood vessels, some of which allow the extravasation of molecules larger than those previously reported. In contrast, the rostral migratory stream (RMS) and the olfactory bulb core (OBc) display mostly impermeable, continuous blood vessels. These results imply that NSCs, TACs, and neuroblasts located within the SVZ are exposed more readily to blood-borne molecules, including those with very high molecular weights, than those positioned along the RMS and the OBc, subregions in which every stage of neurogenesis also takes place. These observations suggest that the existence of specialized vascular niches is not a precondition for neurogenesis to occur; specialized vascular beds might be essential for keeping high rates of proliferation and/or differential differentiation of neural precursors located at distinct domains. PMID:26492830

  18. Quantitative autoradiography of muscarinic and benzodiazepine receptors in the forebrain of the turtle, Pseudemys scripta

    International Nuclear Information System (INIS)

    The distribution of muscarinic and benzodiazepine receptors was investigated in the turtle forebrain by the technique of in vitro receptor autoradiography. Muscarinic binding sites were labeled with 1 nM 3H-quinuclidinyl benzilate (3H-QNB), and benzodiazepine sites were demonstrated with the aid of 1 nM 3H-flunitrazepam (3H-FLU). Autoradiograms generated on 3H-Ultrofilm apposed to tissue slices revealed regionally specific distributions of muscarinic and benzodiazepine binding sites that are comparable with those for mammalian brain. Dense benzodiazepine binding was found in the anterior olfactory nucleus, the lateral and dorsal cortices, and the dorsal ventricular ridge (DVR), a structure with no clear mammalian homologue. Muscarinic binding sites were most dense in the striatum, accumbens, DVR, lateral geniculate, and the anterior olfactory nucleus. Cortical binding sites were studied in greater detail by quantitative analysis of autoradiograms generated by using emulsion-coated coverslips. Laminar gradients of binding were observed that were specific for each radioligand; 3H-QNB sites were most dense in the inner molecular layer in all cortical regions, whereas 3H-FLU binding was generally most concentrated in the outer molecular layer and was least dense through all layers in the dorsomedial cortex. Because pyramidal cells are arranged in register in turtle cortex, the laminar patterns of receptor binding may reflect different receptor density gradients along pyramidal cell dendrites

  19. N-methyl-D-aspartate/phencyclidine receptor complex of rat forebrain: Purification and biochemical characterization

    International Nuclear Information System (INIS)

    The N-methyl-D-aspartate NMDA/phencyclidine (PCP) receptor from rat forebrain was solubilized with sodium cholate and purified by affinity chromatography on amino-PCP-agarose. A 3,700-fold purification was achieved. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and dithiothreitol revealed four major bands of Mr 67,000, 57,000, 46,000, and 33,000. [3H]Azido-PCP was irreversibly incorporated into each of these bands after UV irradiation. The dissociation constant (Kd) of [1-(2-thienyl)cyclohexyl]piperidine ([3H]TCP) binding to the purified NMDA/PCP receptor was 120 nM. The maximum specific binding (Bmax) for [3H]TCP binding was 3.3 nmol/mg of protein. The pharmacological profile of the purified receptor complex was similar to that of the membranal and soluble receptors. The binding of [3H]TCP to the purified receptor was modulated by the NMDA receptor ligands glutamate, glycine, and NMDA

  20. Activation of the hypothalamic paraventricular nucleus by forebrain hypertonicity selectively increases tonic vasomotor sympathetic nerve activity.

    Science.gov (United States)

    Holbein, Walter W; Toney, Glenn M

    2015-03-01

    We recently reported that mean arterial pressure (MAP) is maintained in water-deprived rats by an irregular tonic component of vasomotor sympathetic nerve activity (SNA) that is driven by neuronal activity in the hypothalamic paraventricular nucleus (PVN). To establish whether generation of tonic SNA requires time-dependent (i.e., hours or days of dehydration) neuroadaptive responses or can be abruptly generated by even acute circuit activation, forebrain sympathoexcitatory osmosensory inputs to PVN were stimulated by infusion (0.1 ml/min, 10 min) of hypertonic saline (HTS; 1.5 M NaCl) through an internal carotid artery (ICA). Whereas isotonic saline (ITS; 0.15 M NaCl) had no effect (n = 5), HTS increased (P phosphonovaleric acid (AP5; n = 6) had similar effects. Analysis of respiratory rhythmic bursting of sSNA revealed that ICA HTS increased mean voltage (P < 0.001) without affecting the amplitude of inspiratory or expiratory bursts. Analysis of cardiac rhythmic sSNA likewise revealed that ICA HTS increased mean voltage. Cardiac rhythmic sSNA oscillation amplitude was also increased, which is consistent with activation of arterial baroreceptor during the accompanying pressor response. Increased mean sSNA voltage by HTS was blocked by prior PVN inhibition (muscimol) and blockade of PVN NMDA receptors (AP5). We conclude that even acute glutamatergic activation of PVN (i.e., by hypertonicity) is sufficient to selectively increase a tonic component of vasomotor SNA. PMID:25519737

  1. Cognitive Correlates of Basal Forebrain Atrophy and Associated Cortical Hypometabolism in Mild Cognitive Impairment.

    Science.gov (United States)

    Grothe, Michel J; Heinsen, Helmut; Amaro, Edson; Grinberg, Lea T; Teipel, Stefan J

    2016-06-01

    Degeneration of basal forebrain (BF) cholinergic nuclei is associated with cognitive decline, and this effect is believed to be mediated by neuronal dysfunction in the denervated cortical areas. MRI-based measurements of BF atrophy are increasingly being used as in vivo surrogate markers for cholinergic degeneration, but the functional implications of reductions in BF volume are not well understood. We used high-resolution MRI, fluorodeoxyglucose-positron emission tomography (PET), and neuropsychological test data of 132 subjects with mild cognitive impairment (MCI) and 177 cognitively normal controls to determine associations between BF atrophy, cortical hypometabolism, and cognitive deficits. BF atrophy in MCI correlated with both impaired memory function and attentional control deficits, whereas hippocampus volume was more specifically associated with memory deficits. BF atrophy was also associated with widespread cortical hypometabolism, and path analytic models indicated that hypometabolism in domain-specific cortical networks mediated the association between BF volume and cognitive dysfunction. The presence of cortical amyloid pathology, as assessed using AV45-PET, did not significantly interact with the observed associations. These data underline the potential of multimodal imaging markers to study structure-function-cognition relationships in the living human brain and provide important in vivo evidence for an involvement of the human BF in cortical activity and cognitive function. PMID:25840425

  2. Efficacy of auditory training in elderly subjects

    Directory of Open Access Journals (Sweden)

    Aline Albuquerque Morais

    2015-05-01

    Full Text Available Auditory training (AT  has been used for auditory rehabilitation in elderly individuals and is an effective tool for optimizing speech processing in this population. However, it is necessary to distinguish training-related improvements from placebo and test-retest effects. Thus, we investigated the efficacy of short-term auditory training (acoustically controlled auditory training - ACAT in elderly subjects through behavioral measures and P300. Sixteen elderly individuals with APD received an initial evaluation (evaluation 1 - E1 consisting of behavioral and electrophysiological tests (P300 evoked by tone burst and speech sounds to evaluate their auditory processing. The individuals were divided into two groups. The Active Control Group [ACG (n=8] underwent placebo training. The Passive Control Group [PCG (n=8] did not receive any intervention. After 12 weeks, the subjects were  revaluated (evaluation 2 - E2. Then, all of the subjects underwent ACAT. Following another 12 weeks (8 training sessions, they underwent the final evaluation (evaluation 3 – E3. There was no significant difference between E1 and E2 in the behavioral test [F(9.6=0,.6 p=0.92, λ de Wilks=0.65] or P300 [F(8.7=2.11, p=0.17, λ de Wilks=0.29] (discarding the presence of placebo effects and test-retest. A significant improvement was observed between the pre- and post-ACAT conditions (E2 and E3 for all auditory skills according to the behavioral methods [F(4.27=0.18, p=0.94, λ de Wilks=0.97]. However, the same result was not observed for P300 in any condition. There was no significant difference between P300 stimuli. The ACAT improved the behavioral performance of the elderly for all auditory skills and was an effective method for hearing rehabilitation.

  3. Effects of an Auditory Lateralization Training in Children Suspected to Central Auditory Processing Disorder

    Science.gov (United States)

    Lotfi, Yones; Moosavi, Abdollah; Bakhshi, Enayatollah; Sadjedi, Hamed

    2016-01-01

    Background and Objectives Central auditory processing disorder [(C)APD] refers to a deficit in auditory stimuli processing in nervous system that is not due to higher-order language or cognitive factors. One of the problems in children with (C)APD is spatial difficulties which have been overlooked despite their significance. Localization is an auditory ability to detect sound sources in space and can help to differentiate between the desired speech from other simultaneous sound sources. Aim of this research was investigating effects of an auditory lateralization training on speech perception in presence of noise/competing signals in children suspected to (C)APD. Subjects and Methods In this analytical interventional study, 60 children suspected to (C)APD were selected based on multiple auditory processing assessment subtests. They were randomly divided into two groups: control (mean age 9.07) and training groups (mean age 9.00). Training program consisted of detection and pointing to sound sources delivered with interaural time differences under headphones for 12 formal sessions (6 weeks). Spatial word recognition score (WRS) and monaural selective auditory attention test (mSAAT) were used to follow the auditory lateralization training effects. Results This study showed that in the training group, mSAAT score and spatial WRS in noise (p value≤0.001) improved significantly after the auditory lateralization training. Conclusions We used auditory lateralization training for 6 weeks and showed that auditory lateralization can improve speech understanding in noise significantly. The generalization of this results needs further researches.

  4. Adaptive auditory feedback control of the production of formant trajectories in the Mandarin triphthong /iau/ and its pattern of generalization.

    Science.gov (United States)

    Cai, Shanqing; Ghosh, Satrajit S; Guenther, Frank H; Perkell, Joseph S

    2010-10-01

    In order to test whether auditory feedback is involved in the planning of complex articulatory gestures in time-varying phonemes, the current study examined native Mandarin speakers' responses to auditory perturbations of their auditory feedback of the trajectory of the first formant frequency during their production of the triphthong /iau/. On average, subjects adaptively adjusted their productions to partially compensate for the perturbations in auditory feedback. This result indicates that auditory feedback control of speech movements is not restricted to quasi-static gestures in monophthongs as found in previous studies, but also extends to time-varying gestures. To probe the internal structure of the mechanisms of auditory-motor transformations, the pattern of generalization of the adaptation learned on the triphthong /iau/ to other vowels with different temporal and spatial characteristics (produced only under masking noise) was tested. A broad but weak pattern of generalization was observed; the strength of the generalization diminished with increasing dissimilarity from /iau/. The details and implications of the pattern of generalization are examined and discussed in light of previous sensorimotor adaptation studies of both speech and limb motor control and a neurocomputational model of speech motor control. PMID:20968374

  5. Modification of computational auditory scene analysis (CASA) for noise-robust acoustic feature

    Science.gov (United States)

    Kwon, Minseok

    While there have been many attempts to mitigate interferences of background noise, the performance of automatic speech recognition (ASR) still can be deteriorated by various factors with ease. However, normal hearing listeners can accurately perceive sounds of their interests, which is believed to be a result of Auditory Scene Analysis (ASA). As a first attempt, the simulation of the human auditory processing, called computational auditory scene analysis (CASA), was fulfilled through physiological and psychological investigations of ASA. CASA comprised of Zilany-Bruce auditory model, followed by tracking fundamental frequency for voice segmentation and detecting pairs of onset/offset at each characteristic frequency (CF) for unvoiced segmentation. The resulting Time-Frequency (T-F) representation of acoustic stimulation was converted into acoustic feature, gammachirp-tone frequency cepstral coefficients (GFCC). 11 keywords with various environmental conditions are used and the robustness of GFCC was evaluated by spectral distance (SD) and dynamic time warping distance (DTW). In "clean" and "noisy" conditions, the application of CASA generally improved noise robustness of the acoustic feature compared to a conventional method with or without noise suppression using MMSE estimator. The intial study, however, not only showed the noise-type dependency at low SNR, but also called the evaluation methods in question. Some modifications were made to capture better spectral continuity from an acoustic feature matrix, to obtain faster processing speed, and to describe the human auditory system more precisely. The proposed framework includes: 1) multi-scale integration to capture more accurate continuity in feature extraction, 2) contrast enhancement (CE) of each CF by competition with neighboring frequency bands, and 3) auditory model modifications. The model modifications contain the introduction of higher Q factor, middle ear filter more analogous to human auditory system

  6. In-air hearing of a diving duck: A comparison of psychoacoustic and auditory brainstem response thresholds.

    Science.gov (United States)

    Crowell, Sara E; Wells-Berlin, Alicia M; Therrien, Ronald E; Yannuzzi, Sally E; Carr, Catherine E

    2016-05-01

    Auditory sensitivity was measured in a species of diving duck that is not often kept in captivity, the lesser scaup. Behavioral (psychoacoustics) and electrophysiological [the auditory brainstem response (ABR)] methods were used to measure in-air auditory sensitivity, and the resulting audiograms were compared. Both approaches yielded audiograms with similar U-shapes and regions of greatest sensitivity (2000-3000 Hz). However, ABR thresholds were higher than psychoacoustic thresholds at all frequencies. This difference was least at the highest frequency tested using both methods (5700 Hz) and greatest at 1000 Hz, where the ABR threshold was 26.8 dB higher than the behavioral measure of threshold. This difference is commonly reported in studies involving many different species. These results highlight the usefulness of each method, depending on the testing conditions and availability of the animals. PMID:27250191

  7. Dynamics of distraction: competition among auditory streams modulates gain and disrupts inter-trial phase coherence in the human electroencephalogram.

    Directory of Open Access Journals (Sweden)

    Karla D Ponjavic-Conte

    Full Text Available Auditory distraction is a failure to maintain focus on a stream of sounds. We investigated the neural correlates of distraction in a selective-listening pitch-discrimination task with high (competing speech or low (white noise distraction. High-distraction impaired performance and reduced the N1 peak of the auditory Event-Related Potential evoked by probe tones. In a series of simulations, we explored two theories to account for this effect: disruption of sensory gain or a disruption of inter-trial phase consistency. When compared to these simulations, our data were consistent with both effects of distraction. Distraction reduced the gain of the auditory evoked potential and disrupted the inter-trial phase consistency with which the brain responds to stimulus events. Tones at a non-target, unattended frequency were more susceptible to the effects of distraction than tones within an attended frequency band.

  8. Dynamics of distraction: competition among auditory streams modulates gain and disrupts inter-trial phase coherence in the human electroencephalogram.

    Science.gov (United States)

    Ponjavic-Conte, Karla D; Hambrook, Dillon A; Pavlovic, Sebastian; Tata, Matthew S

    2013-01-01

    Auditory distraction is a failure to maintain focus on a stream of sounds. We investigated the neural correlates of distraction in a selective-listening pitch-discrimination task with high (competing speech) or low (white noise) distraction. High-distraction impaired performance and reduced the N1 peak of the auditory Event-Related Potential evoked by probe tones. In a series of simulations, we explored two theories to account for this effect: disruption of sensory gain or a disruption of inter-trial phase consistency. When compared to these simulations, our data were consistent with both effects of distraction. Distraction reduced the gain of the auditory evoked potential and disrupted the inter-trial phase consistency with which the brain responds to stimulus events. Tones at a non-target, unattended frequency were more susceptible to the effects of distraction than tones within an attended frequency band. PMID:23326548

  9. Auditory and motor imagery modulate learning in music performance

    Science.gov (United States)

    Brown, Rachel M.; Palmer, Caroline

    2013-01-01

    Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians' encoding (during Learning, as they practiced novel melodies), and retrieval (during Recall of those melodies). Pianists learned melodies by listening without performing (auditory learning) or performing without sound (motor learning); following Learning, pianists performed the melodies from memory with auditory feedback (Recall). During either Learning (Experiment 1) or Recall (Experiment 2), pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced) and temporal regularity (variability of quarter-note interonset intervals) were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists' pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2). Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1): Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2): Higher auditory imagery skill predicted greater temporal regularity during Recall in the presence of

  10. Auditory and motor imagery modulate learning in music performance.

    Science.gov (United States)

    Brown, Rachel M; Palmer, Caroline

    2013-01-01

    Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians' encoding (during Learning, as they practiced novel melodies), and retrieval (during Recall of those melodies). Pianists learned melodies by listening without performing (auditory learning) or performing without sound (motor learning); following Learning, pianists performed the melodies from memory with auditory feedback (Recall). During either Learning (Experiment 1) or Recall (Experiment 2), pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced) and temporal regularity (variability of quarter-note interonset intervals) were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists' pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2). Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1): Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2): Higher auditory imagery skill predicted greater temporal regularity during Recall in the presence of

  11. Acute Auditory Stimulation with Different Styles of Music Influences Cardiac Autonomic Regulation in Men

    Directory of Open Access Journals (Sweden)

    Sheila Ap. F. da Silva

    2014-09-01

    Full Text Available Background: No clear evidence is available in the literature regarding the acute effect of different styles of music on cardiac autonomic control. Objectives: The present study aimed to evaluate the acute effects of classical baroque and heavy metal musical auditory stimulation on Heart Rate Variability (HRV in healthy men. Patients and Methods: In this study, HRV was analyzed regarding time (SDNN, RMSSD, NN50, and pNN50 and frequency domain (LF, HF, and LF / HF in 12 healthy men. HRV was recorded at seated rest for 10 minutes. Subsequently, the participants were exposed to classical baroque or heavy metal music for five minutes through an earphone at seated rest. After exposure to the first song, they remained at rest for five minutes and they were again exposed to classical baroque or heavy metal music. The music sequence was random for each individual. Standard statistical methods were used for calculation of means and standard deviations. Besides, ANOVA and Friedman test were used for parametric and non-parametric distributions, respectively. Results: While listening to heavy metal music, SDNN was reduced compared to the baseline (P = 0.023. In addition, the LF index (ms2 and nu was reduced during exposure to both heavy metal and classical baroque musical auditory stimulation compared to the control condition (P = 0.010 and P = 0.048, respectively. However, the HF index (ms2 was reduced only during auditory stimulation with music heavy metal (P = 0.01. The LF/HF ratio on the other hand decreased during auditory stimulation with classical baroque music (P = 0.019. Conclusions: Acute auditory stimulation with the selected heavy metal musical auditory stimulation decreased the sympathetic and parasympathetic modulation on the heart, while exposure to a selected classical baroque music reduced sympathetic regulation on the heart.

  12. The Effect of Adaptation on the Tuning Curves of Rat Auditory Cortex

    Science.gov (United States)

    Parto Dezfouli, Mohsen; Daliri, Mohammad Reza

    2015-01-01

    Repeated stimulus causes a specific suppression of neuronal responses, which is so-called as Stimulus-Specific Adaptation (SSA). This effect can be recovered when the stimulus changes. In the auditory system SSA is a well-known phenomenon that appears at different levels of the mammalian auditory pathway. In this study, we explored the effects of adaptation to a particular stimulus on the auditory tuning curves of anesthetized rats. We used two sequences and compared the responses of each tone combination in these two conditions. First sequence consists of different pure tone combinations that were presented randomly. In the second one, the same stimuli of the first sequence were presented in the context of an adapted stimulus (adapter) that occupied 80% of sequence probability. The population results demonstrated that the adaptation factor decreased the frequency response area and made a change in the tuning curve to shift it unevenly toward the higher thresholds of tones. The local field potentials and multi-unit activity responses have indicated that the neural activities strength of the adapted frequency has been suppressed as well as with lower suppression in neighboring frequencies. This aforementioned reduction changed the characteristic frequency of the tuning curve. PMID:25719404

  13. Auditory Model Identification Using REVCOR Method

    Directory of Open Access Journals (Sweden)

    Lamia Bouafif

    2014-08-01

    Full Text Available Auditory models are very useful in many applications such as speech coding and compression, cochlea prosthesis, and audio watermarking. In this paper we will develop a new auditory model based on the REVCOR method. This technique is based on the estimation of the impulse response of a suitable filter characterizing the auditory neuron and the cochlea. The first step of our study is focused on the development of a mathematical model based on the gammachirp system. This model is then programmed, implemented and simulated under Matlab. The obtained results are compared with the experimental values (REVCOR experiments for the validation and a better optimization of the model parameters. Two objective criteria are used in order to optimize the audio model estimation which are the SNR (signal to noise ratio and the MQE (mean quadratic error. The simulation results demonstrated that for the auditory model, only a reduced number of channels are excited (from 3 to 6. This result is very interesting for auditory implants because only significant channels will be stimulated. Besides, this simplifies the electronic implementation and medical intervention.

  14. 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.

  15. Expression and function of scleraxis in the developing auditory system.

    Directory of Open Access Journals (Sweden)

    Zoe F Mann

    Full Text Available A study of genes expressed in the developing inner ear identified the bHLH transcription factor Scleraxis (Scx in the developing cochlea. Previous work has demonstrated an essential role for Scx in the differentiation and development of tendons, ligaments and cells of chondrogenic lineage. Expression in the cochlea has been shown previously, however the functional role for Scx in the cochlea is unknown. Using a Scx-GFP reporter mouse line we examined the spatial and temporal patterns of Scx expression in the developing cochlea between embryonic day 13.5 and postnatal day 25. Embryonically, Scx is expressed broadly throughout the cochlear duct and surrounding mesenchyme and at postnatal ages becomes restricted to the inner hair cells and the interdental cells of the spiral limbus. Deletion of Scx results in hearing impairment indicated by elevated auditory brainstem response (ABR thresholds and diminished distortion product otoacoustic emission (DPOAE amplitudes, across a range of frequencies. No changes in either gross cochlear morphology or expression of the Scx target genes Col2A, Bmp4 or Sox9 were observed in Scx(-/- mutants, suggesting that the auditory defects observed in these animals may be a result of unidentified Scx-dependent processes within the cochlea.

  16. The effect of background music in auditory health persuasion

    NARCIS (Netherlands)

    Elbert, Sarah; Dijkstra, Arie

    2013-01-01

    In auditory health persuasion, threatening information regarding health is communicated by voice only. One relevant context of auditory persuasion is the addition of background music. There are different mechanisms through which background music might influence persuasion, for example through mood (

  17. Musical experience shapes top-down auditory mechanisms: evidence from masking and auditory attention performance.

    Science.gov (United States)

    Strait, Dana L; Kraus, Nina; Parbery-Clark, Alexandra; Ashley, Richard

    2010-03-01

    A growing body of research suggests that cognitive functions, such as attention and memory, drive perception by tuning sensory mechanisms to relevant acoustic features. Long-term musical experience also modulates lower-level auditory function, although the mechanisms by which this occurs remain uncertain. In order to tease apart the mechanisms that drive perceptual enhancements in musicians, we posed the question: do well-developed cognitive abilities fine-tune auditory perception in a top-down fashion? We administered a standardized battery of perceptual and cognitive tests to adult musicians and non-musicians, including tasks either more or less susceptible to cognitive control (e.g., backward versus simultaneous masking) and more or less dependent on auditory or visual processing (e.g., auditory versus visual attention). Outcomes indicate lower perceptual thresholds in musicians specifically for auditory tasks that relate with cognitive abilities, such as backward masking and auditory attention. These enhancements were observed in the absence of group differences for the simultaneous masking and visual attention tasks. Our results suggest that long-term musical practice strengthens cognitive functions and that these functions benefit auditory skills. Musical training bolsters higher-level mechanisms that, when impaired, relate to language and literacy deficits. Thus, musical training may serve to lessen the impact of these deficits by strengthening the corticofugal system for hearing. PMID:20018234

  18. Electrophysiological correlates of auditory change detection and change deafness in complex auditory scenes.

    Science.gov (United States)

    Puschmann, Sebastian; Sandmann, Pascale; Ahrens, Janina; Thorne, Jeremy; Weerda, Riklef; Klump, Georg; Debener, Stefan; Thiel, Christiane M

    2013-07-15

    Change deafness describes the failure to perceive even intense changes within complex auditory input, if the listener does not attend to the changing sound. Remarkably, previous psychophysical data provide evidence that this effect occurs independently of successful stimulus encoding, indicating that undetected changes are processed to some extent in auditory cortex. Here we investigated cortical representations of detected and undetected auditory changes using electroencephalographic (EEG) recordings and a change deafness paradigm. We applied a one-shot change detection task, in which participants listened successively to three complex auditory scenes, each of them consisting of six simultaneously presented auditory streams. Listeners had to decide whether all scenes were identical or whether the pitch of one stream was changed between the last two presentations. Our data show significantly increased middle-latency Nb responses for both detected and undetected changes as compared to no-change trials. In contrast, only successfully detected changes were associated with a later mismatch response in auditory cortex, followed by increased N2, P3a and P3b responses, originating from hierarchically higher non-sensory brain regions. These results strengthen the view that undetected changes are successfully encoded at sensory level in auditory cortex, but fail to trigger later change-related cortical responses that lead to conscious perception of change. PMID:23466938

  19. What determines auditory distraction? On the roles of local auditory changes and expectation violations.

    Directory of Open Access Journals (Sweden)

    Jan P Röer

    Full Text Available Both the acoustic variability of a distractor sequence and the degree to which it violates expectations are important determinants of auditory distraction. In four experiments we examined the relative contribution of local auditory changes on the one hand and expectation violations on the other hand in the disruption of serial recall by irrelevant sound. We present evidence for a greater disruption by auditory sequences ending in unexpected steady state distractor repetitions compared to auditory sequences with expected changing state endings even though the former contained fewer local changes. This effect was demonstrated with piano melodies (Experiment 1 and speech distractors (Experiment 2. Furthermore, it was replicated when the expectation violation occurred after the encoding of the target items (Experiment 3, indicating that the items' maintenance in short-term memory was disrupted by attentional capture and not their encoding. This seems to be primarily due to the violation of a model of the specific auditory distractor sequences because the effect vanishes and even reverses when the experiment provides no opportunity to build up a specific neural model about the distractor sequence (Experiment 4. Nevertheless, the violation of abstract long-term knowledge about auditory regularities seems to cause a small and transient capture effect: Disruption decreased markedly over the course of the experiments indicating that participants habituated to the unexpected distractor repetitions across trials. The overall pattern of results adds to the growing literature that the degree to which auditory distractors violate situation-specific expectations is a more important determinant of auditory distraction than the degree to which a distractor sequence contains local auditory changes.

  20. What Determines Auditory Distraction? On the Roles of Local Auditory Changes and Expectation Violations

    Science.gov (United States)

    Röer, Jan P.; Bell, Raoul; Buchner, Axel

    2014-01-01

    Both the acoustic variability of a distractor sequence and the degree to which it violates expectations are important determinants of auditory distraction. In four experiments we examined the relative contribution of local auditory changes on the one hand and expectation violations on the other hand in the disruption of serial recall by irrelevant sound. We present evidence for a greater disruption by auditory sequences ending in unexpected steady state distractor repetitions compared to auditory sequences with expected changing state endings even though the former contained fewer local changes. This effect was demonstrated with piano melodies (Experiment 1) and speech distractors (Experiment 2). Furthermore, it was replicated when the expectation violation occurred after the encoding of the target items (Experiment 3), indicating that the items' maintenance in short-term memory was disrupted by attentional capture and not their encoding. This seems to be primarily due to the violation of a model of the specific auditory distractor sequences because the effect vanishes and even reverses when the experiment provides no opportunity to build up a specific neural model about the distractor sequence (Experiment 4). Nevertheless, the violation of abstract long-term knowledge about auditory regularities seems to cause a small and transient capture effect: Disruption decreased markedly over the course of the experiments indicating that participants habituated to the unexpected distractor repetitions across trials. The overall pattern of results adds to the growing literature that the degree to which auditory distractors violate situation-specific expectations is a more important determinant of auditory distraction than the degree to which a distractor sequence contains local auditory changes. PMID:24400081

  1. Applied research in auditory data representation

    Science.gov (United States)

    Frysinger, Steve P.

    1990-08-01

    A class of data displays, characterized generally as Auditory Data Representation, is described and motivated. This type of data representation takes advantage of the tremendous pattern recognition capability of the human auditory channel. Audible displays offer an alternative means of conveying quantitative data to the analyst to facilitate information extraction, and are successfully used alone and in conjunction with visual displays. The Auditory Data Representation literature is reviewed, along with elements of the allied fields of investigation, Psychoacoustics and Musical Perception. A methodology for applied research in this field, based upon the well-developed discipline of psychophysics, is elaborated using a recent experiment as a case study. This method permits objective estimation of a data representation technique by comparing it to alternative displays for the pattern recognition task at hand. The psychophysical threshold of signal to noise level, for constant pattern recognition performance, is the measure of display effectiveness.

  2. Cooperative dynamics in auditory brain response

    CERN Document Server

    Kwapien, J; Liu, L C; Ioannides, A A

    1998-01-01

    Simultaneous estimates of the activity in the left and right auditory cortex of five normal human subjects were extracted from Multichannel Magnetoencephalography recordings. Left, right and binaural stimulation were used, in separate runs, for each subject. The resulting time-series of left and right auditory cortex activity were analysed using the concept of mutual information. The analysis constitutes an objective method to address the nature of inter-hemispheric correlations in response to auditory stimulations. The results provide a clear evidence for the occurrence of such correlations mediated by a direct information transport, with clear laterality effects: as a rule, the contralateral hemisphere leads by 10-20ms, as can be seen in the average signal. The strength of the inter-hemispheric coupling, which cannot be extracted from the average data, is found to be highly variable from subject to subject, but remarkably stable for each subject.

  3. A Circuit for Motor Cortical Modulation of Auditory Cortical Activity

    OpenAIRE

    Nelson, Anders; Schneider, David M.; Takatoh, Jun; Sakurai, Katsuyasu; Wang, Fan; Mooney, Richard

    2013-01-01

    Normal hearing depends on the ability to distinguish self-generated sounds from other sounds, and this ability is thought to involve neural circuits that convey copies of motor command signals to various levels of the auditory system. Although such interactions at the cortical level are believed to facilitate auditory comprehension during movements and drive auditory hallucinations in pathological states, the synaptic organization and function of circuitry linking the motor and auditory corti...

  4. Auditory and motor imagery modulate learning in music performance

    Directory of Open Access Journals (Sweden)

    Rachel M. Brown

    2013-07-01

    Full Text Available Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians’ encoding (during Learning, as they practiced novel melodies, and retrieval (during Recall of those melodies. Pianists learned melodies by listening without performing (auditory learning or performing without sound (motor learning; following Learning, pianists performed the melodies from memory with auditory feedback (Recall. During either Learning (Experiment 1 or Recall (Experiment 2, pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced and temporal regularity (variability of quarter-note interonset intervals were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists’ pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2. Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1: Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2: Higher auditory imagery skill predicted greater temporal regularity during Recall in the

  5. Functional neuroanatomy of auditory scene analysis in Alzheimer's disease

    OpenAIRE

    Golden, Hannah L.; Jennifer L. Agustus; Johanna C. Goll; Downey, Laura E; Mummery, Catherine J.; Jonathan M Schott; Crutch, Sebastian J.; Jason D Warren

    2015-01-01

    Auditory scene analysis is a demanding computational process that is performed automatically and efficiently by the healthy brain but vulnerable to the neurodegenerative pathology of Alzheimer's disease. Here we assessed the functional neuroanatomy of auditory scene analysis in Alzheimer's disease using the well-known ‘cocktail party effect’ as a model paradigm whereby stored templates for auditory objects (e.g., hearing one's spoken name) are used to segregate auditory ‘foreground’ and ‘back...

  6. Behavioral correlates of auditory streaming in rhesus macaques

    OpenAIRE

    Christison-Lagay, Kate L.; Cohen, Yale E.

    2013-01-01

    Perceptual representations of auditory stimuli (i.e., sounds) are derived from the auditory system’s ability to segregate and group the spectral, temporal, and spatial features of auditory stimuli—a process called “auditory scene analysis”. Psychophysical studies have identified several of the principles and mechanisms that underlie a listener’s ability to segregate and group acoustic stimuli. One important psychophysical task that has illuminated many of these principles and mechanisms is th...

  7. Auditory ERP response to successive stimuli in infancy

    OpenAIRE

    Chen, Ao; Peter, Varghese; Burnham, Denis

    2016-01-01

    Background. Auditory Event-Related Potentials (ERPs) are useful for understanding early auditory development among infants, as it allows the collection of a relatively large amount of data in a short time. So far, studies that have investigated development in auditory ERPs in infancy have mainly used single sounds as stimuli. Yet in real life, infants must decode successive rather than single acoustic events. In the present study, we tested 4-, 8-, and 12-month-old infants’ auditory ERPs to m...

  8. Auditory Neuropathy Spectrum Disorder Masquerading as Social Anxiety

    OpenAIRE

    Behere, Rishikesh V.; Rao, Mukund G.; Mishra, Shree; Varambally, Shivarama; Nagarajarao, Shivashankar; Bangalore N Gangadhar

    2015-01-01

    The authors report a case of a 47-year-old man who presented with treatment-resistant anxiety disorder. Behavioral observation raised clinical suspicion of auditory neuropathy spectrum disorder. The presence of auditory neuropathy spectrum disorder was confirmed on audiological investigations. The patient was experiencing extreme symptoms of anxiety, which initially masked the underlying diagnosis of auditory neuropathy spectrum disorder. Challenges in diagnosis and treatment of auditory neur...

  9. Deep transcranial magnetic stimulation add-on for the treatment of auditory hallucinations: a double-blind study

    Directory of Open Access Journals (Sweden)

    Rosenberg Oded

    2012-05-01

    Full Text Available Abstract Background About 25% of schizophrenia patients with auditory hallucinations are refractory to pharmacotherapy and electroconvulsive therapy. We conducted a deep transcranial magnetic stimulation (TMS pilot study in order to evaluate the potential clinical benefit of repeated left temporoparietal cortex stimulation in these patients. The results were encouraging, but a sham-controlled study was needed to rule out a placebo effect. Methods A total of 18 schizophrenic patients with refractory auditory hallucinations were recruited, from Beer Yaakov MHC and other hospitals outpatient populations. Patients received 10 daily treatment sessions with low-frequency (1 Hz for 10 min deep TMS applied over the left temporoparietal cortex, using the H1 coil at the intensity of 110% of the motor threshold. Procedure was either real or sham according to patient randomization. Patients were evaluated via the Auditory Hallucinations Rating Scale, Scale for the Assessment of Positive Symptoms-Negative Symptoms, Clinical Global Impressions, and Quality of Life Questionnaire. Results In all, 10 patients completed the treatment (10 TMS sessions. Auditory hallucination scores of both groups improved; however, there was no statistical difference in any of the scales between the active and the sham treated groups. Conclusions Low-frequency deep TMS to the left temporoparietal cortex using the protocol mentioned above has no statistically significant effect on auditory hallucinations or the other clinical scales measured in schizophrenic patients. Trial Registration Clinicaltrials.gov identifier: NCT00564096.

  10. Electrophysiological mismatch response recorded in awake pigeons from the avian functional equivalent of the primary auditory cortex.

    Science.gov (United States)

    Schall, Ulrich; Müller, Bernhard W; Kärgel, Christian; Güntürkün, Onur

    2015-03-25

    The neural response to occasional variations in acoustic stimuli in a regular sequence of sounds generates an N-methyl-D-aspartate receptor-modulated event-related potential in primates and rodents in the primary auditory cortex known as mismatch negativity (MMN). The current study investigated MMN in pigeons (Columba livia L) through intracranial recordings from Field L of the caudomedial nidopallium, the avian functional equivalent of the mammalian primary auditory cortex. Auditory evoked field potentials were recorded from awake birds using a low-frequency (800 Hz) and high-frequency (1400 Hz) deviant auditory oddball procedure with deviant-as-standard (flip-flop design) and multiple-standard control conditions. An MMN-like field potential was recorded and blocked with systemic 5 mg/kg ketamine administration. Our results are similar to human and rodent findings of an MMN-like event-related potential in birds suggestive of similar auditory sensory memory mechanisms in birds and mammals that are homologue from a common ancestor 300 million years ago or resulted from convergent evolution. PMID:25646582

  11. Failed stabilization for long-term potentiation in the auditory cortex of FMR1 knockout mice.

    Directory of Open Access Journals (Sweden)

    Sungchil Yang

    Full Text Available Fragile X syndrome is a developmental disorder that affects sensory systems. A null mutation of the Fragile X Mental Retardation protein 1 (Fmr1 gene in mice has varied effects on developmental plasticity in different sensory systems, including normal barrel cortical plasticity, altered ocular dominance plasticity and grossly impaired auditory frequency map plasticity. The mutation also has different effects on long-term synaptic plasticity in somatosensory and visual cortical neurons, providing insights on how it may differentially affect the sensory systems. Here we present evidence that long-term potentiation (LTP is impaired in the developing auditory cortex of the Fmr1 knockout (KO mice. This impairment of synaptic plasticity is consistent with impaired frequency map plasticity in the Fmr1 KO mouse. Together, these results suggest a potential role of LTP in sensory map plasticity during early sensory development.

  12. Utilising reinforcement learning to develop strategies for driving auditory neural implants

    Science.gov (United States)

    Lee, Geoffrey W.; Zambetta, Fabio; Li, Xiaodong; Paolini, Antonio G.

    2016-08-01

    Objective. In this paper we propose a novel application of reinforcement learning to the area of auditory neural stimulation. We aim to develop a simulation environment which is based off real neurological responses to auditory and electrical stimulation in the cochlear nucleus (CN) and inferior colliculus (IC) of an animal model. Using this simulator we implement closed loop reinforcement learning algorithms to determine which methods are most effective at learning effective acoustic neural stimulation strategies. Approach. By recording a comprehensive set of acoustic frequency presentations and neural responses from a set of animals we created a large database of neural responses to acoustic stimulation. Extensive electrical stimulation in the CN and the recording of neural responses in the IC provides a mapping of how the auditory system responds to electrical stimuli. The combined dataset is used as the foundation for the simulator, which is used to implement and test learning algorithms. Main results. Reinforcement learning, utilising a modified n-Armed Bandit solution, is implemented to demonstrate the model’s function. We show the ability to effectively learn stimulation patterns which mimic the cochlea’s ability to covert acoustic frequencies to neural activity. Time taken to learn effective replication using neural stimulation takes less than 20 min under continuous testing. Significance. These results show the utility of reinforcement learning in the field of neural stimulation. These results can be coupled with existing sound processing technologies to develop new auditory prosthetics that are adaptable to the recipients current auditory pathway. The same process can theoretically be abstracted to other sensory and motor systems to develop similar electrical replication of neural signals.

  13. Auditory Brainstem Response Improvements in Hyperbillirubinemic Infants

    Science.gov (United States)

    Abdollahi, Farzaneh Zamiri; Manchaiah, Vinaya; Lotfi, Yones

    2016-01-01

    Background and Objectives Hyperbillirubinemia in infants have been associated with neuronal damage including in the auditory system. Some researchers have suggested that the bilirubin-induced auditory neuronal damages may be temporary and reversible. This study was aimed at investigating the auditory neuropathy and reversibility of auditory abnormalities in hyperbillirubinemic infants. Subjects and Methods The study participants included 41 full term hyperbilirubinemic infants (mean age 39.24 days) with normal birth weight (3,200-3,700 grams) that admitted in hospital for hyperbillirubinemia and 39 normal infants (mean age 35.54 days) without any hyperbillirubinemia or other hearing loss risk factors for ruling out maturational changes. All infants in hyperbilirubinemic group had serum bilirubin level more than 20 milligram per deciliter and undergone one blood exchange transfusion. Hearing evaluation for each infant was conducted twice: the first one after hyperbilirubinemia treatment and before leaving hospital and the second one three months after the first hearing evaluation. Hearing evaluations included transient evoked otoacoustic emission (TEOAE) screening and auditory brainstem response (ABR) threshold tracing. Results The TEOAE and ABR results of control group and TEOAE results of the hyperbilirubinemic group did not change significantly from the first to the second evaluation. However, the ABR results of the hyperbilirubinemic group improved significantly from the first to the second assessment (p=0.025). Conclusions The results suggest that the bilirubin induced auditory neuronal damage can be reversible over time so we suggest that infants with hyperbilirubinemia who fail the first hearing tests should be reevaluated after 3 months of treatment. PMID:27144228

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

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel

    A loudspeaker-based virtual auditory environment (VAE) has been developed to provide a realistic versatile research environment for investigating the auditory signal processing in real environments, i.e., considering multiple sound sources and room reverberation. The VAE allows a full control of...... the acoustic scenario in order to systematically study the auditory processing of reverberant sounds. It is based on the ODEON software, which is state-of-the-art software for room acoustic simulations developed at Acoustic Technology, DTU. First, a MATLAB interface to the ODEON software has been...

  15. Can comodulation masking release occur when frequency changes could promote perceptual segregation of the on-frequency and flanking bands?

    DEFF Research Database (Denmark)

    Verhey, Jesko L; Epp, Bastian; Stasiak, Arkadiusz;

    2013-01-01

    A common characteristic of natural sounds is that the level fluctuations in different frequency regions are coherent. The ability of the auditory system to use this comodulation is shown when a sinusoidal signal is masked by a masker centred at the signal frequency (on-frequency masker, OFM) and...... bands relative to the inhibitory areas (as seen in physiological recordings using stationary flanking bands). Preliminary physiological results in the cochlear nucleus of the Guinea pig show that a correlate of CMR can also be found at this level of the auditory pathway with sweeping flanking bands....

  16. Auditory Hypersensitivity in Children with Autism Spectrum Disorders

    Science.gov (United States)

    Lucker, Jay R.

    2013-01-01

    A review of records was completed to determine whether children with auditory hypersensitivities have difficulty tolerating loud sounds due to auditory-system factors or some other factors not directly involving the auditory system. Records of 150 children identified as not meeting autism spectrum disorders (ASD) criteria and another 50 meeting…

  17. AN EVALUATION OF AUDITORY LEARNING IN FILIAL IMPRINTING

    NARCIS (Netherlands)

    BOLHUIS, JJ; VANKAMPEN, HS

    1992-01-01

    The characteristics of auditory learning in filial imprinting in precocial birds are reviewed. Numerous studies have demonstrated that the addition of an auditory stimulus improves following of a visual stimulus. This paper evaluates whether there is genuine auditory imprinting, i.e. the formation o

  18. Auditory Stream Biasing in Children with Reading Impairments

    Science.gov (United States)

    Ouimet, Tialee; Balaban, Evan

    2010-01-01

    Reading impairments have previously been associated with auditory processing differences. We examined "auditory stream biasing", a global aspect of auditory temporal processing. Children with reading impairments, control children and adults heard a 10 s long stream-bias-inducing sound sequence (a repeating 1000 Hz tone) and a test sequence (eight…

  19. Auditory issues in handheld land mine detectors

    Science.gov (United States)

    Vause, Nancy L.; Letowski, Tomasz R.; Ferguson, Larry G.; Mermagen, Timothy J.

    1999-08-01

    Most handled landmine detection systems use tones or other simple acoustic signals to provide detector information to the operator. Such signals are not necessarily the best carriers of information about the characteristics of hidden objects. To be effective, the auditory signals must present the information in a manner that the operator can comfortably and efficiently, the auditory signals must present the information in a manner that the operator can comfortably and efficiently interpret under stress and high mental load. The signals must also preserve their audibility and specific properties in various adverse acoustic environments. This paper will present several issues on optimizing the audio display interface between the operator and machine.

  20. Auditory Perception of Statistically Blurred Sound Textures

    DEFF Research Database (Denmark)

    McWalter, Richard Ian; MacDonald, Ewen; Dau, Torsten

    Sound textures have been identified as a category of sounds which are processed by the peripheral auditory system and captured with running timeaveraged statistics. Although sound textures are temporally homogeneous, they offer a listener with enough information to identify and differentiate...... sources. This experiment investigated the ability of the auditory system to identify statistically blurred sound textures and the perceptual relationship between sound textures. Identification performance of statistically blurred sound textures presented at a fixed blur increased over those presented as a...... gradual blur. The results suggests that the correct identification of sound textures is influenced by the preceding blurred stimulus. These findings draw parallels to the recognition of blurred images....

  1. 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...

  2. Higher sensitivity to cadmium induced cell death of basal forebrain cholinergic neurons: A cholinesterase dependent mechanism

    International Nuclear Information System (INIS)

    Cadmium is an environmental pollutant, which is a cause of concern because it can be greatly concentrated in the organism causing severe damage to a variety of organs including the nervous system which is one of the most affected. Cadmium has been reported to produce learning and memory dysfunctions and Alzheimer like symptoms, though the mechanism is unknown. On the other hand, cholinergic system in central nervous system (CNS) is implicated on learning and memory regulation, and it has been reported that cadmium can affect cholinergic transmission and it can also induce selective toxicity on cholinergic system at peripheral level, producing cholinergic neurons loss, which may explain cadmium effects on learning and memory processes if produced on central level. The present study is aimed at researching the selective neurotoxicity induced by cadmium on cholinergic system in CNS. For this purpose we evaluated, in basal forebrain region, the cadmium toxic effects on neuronal viability and the cholinergic mechanisms related to it on NS56 cholinergic mourine septal cell line. This study proves that cadmium induces a more pronounced, but not selective, cell death on acetylcholinesterase (AChE) on cholinergic neurons. Moreover, MTT and LDH assays showed a dose dependent decrease of cell viability in NS56 cells. The ACh treatment of SN56 cells did not revert cell viability reduction induced by cadmium, but siRNA transfection against AChE partially reduced it. Our present results provide new understanding of the mechanisms contributing to the harmful effects of cadmium on the function and viability of neurons, and the possible relevance of cadmium in the pathogenesis of neurodegenerative diseases

  3. The Forebrain Song System Mediates Predictive Call Timing in Female and Male Zebra Finches.

    Science.gov (United States)

    Benichov, Jonathan I; Benezra, Sam E; Vallentin, Daniela; Globerson, Eitan; Long, Michael A; Tchernichovski, Ofer

    2016-02-01

    The dichotomy between vocal learners and non-learners is a fundamental distinction in the study of animal communication. Male zebra finches (Taeniopygia guttata) are vocal learners that acquire a song resembling their tutors', whereas females can only produce innate calls. The acoustic structure of short calls, produced by both males and females, is not learned. However, these calls can be precisely coordinated across individuals. To examine how birds learn to synchronize their calls, we developed a vocal robot that exchanges calls with a partner bird. Because birds answer the robot with stereotyped latencies, we could program it to disrupt each bird's responses by producing calls that are likely to coincide with the bird's. Within minutes, the birds learned to avoid this disruptive masking (jamming) by adjusting the timing of their responses. Notably, females exhibited greater adaptive timing plasticity than males. Further, when challenged with complex rhythms containing jamming elements, birds dynamically adjusted the timing of their calls in anticipation of jamming. Blocking the song system cortical output dramatically reduced the precision of birds' response timing and abolished their ability to avoid jamming. Surprisingly, we observed this effect in both males and females, indicating that the female song system is functional rather than vestigial. We suggest that descending forebrain projections, including the song-production pathway, function as a general-purpose sensorimotor communication system. In the case of calls, it enables plasticity in vocal timing to facilitate social interactions, whereas in the case of songs, plasticity extends to developmental changes in vocal structure. PMID:26774786

  4. Topographic organization of the basal forebrain projections to the perirhinal, postrhinal, and entorhinal cortex in rats.

    Science.gov (United States)

    Kondo, Hideki; Zaborszky, Laszlo

    2016-08-15

    Previous studies have shown that the basal forebrain (BF) modulates cortical activation via its projections to the entire cortical mantle. However, the organization of these projections is only partially understood or, for certain areas, unknown. In this study, we examined the topographic organization of cholinergic and noncholinergic projections from the BF to the perirhinal, postrhinal, and entorhinal cortex by using retrograde tracing combined with choline acetyltransferase (ChAT) immunohistochemistry in rats. The perirhinal and postrhinal cortex receives major cholinergic and noncholinergic input from the caudal BF, including the caudal globus pallidus and substantia innominata and moderate input from the horizontal limb of the diagonal band, whereas the entorhinal cortex receives major input from the rostral BF, including the medial septum and the vertical and horizontal limbs of the diagonal band. In the perirhinal cases, cholinergic projection neurons are distributed more caudally in the caudal globus pallidus than noncholinergic projection neurons. Compared with the perirhinal cases, the distribution of cholinergic and noncholinergic neurons projecting to the postrhinal cortex shifts slightly caudally in the caudal globus pallidus. The distribution of cholinergic and noncholinergic neurons projecting to the lateral entorhinal cortex extends more caudally in the BF than to the medial entorhinal cortex. The ratio of ChAT-positive projection neurons to total projection neurons is higher in the perirhinal/postrhinal cases (26-48%) than in the entorhinal cases (13-30%). These results indicate that the organization of cholinergic and noncholinergic projections from the BF to the parahippocampal cortex is more complex than previously described. J. Comp. Neurol. 524:2503-2515, 2016. © 2016 Wiley Periodicals, Inc. PMID:26780730

  5. How musical expertise shapes speech perception: Evidence from auditory classification images

    OpenAIRE

    Léo Varnet; Tianyun Wang; Chloe Peter; Fanny Meunier; Michel Hoen

    2015-01-01

    It is now well established that extensive musical training percolates to higher levels of cognition, such as speech processing. However, the lack of a precise technique to investigate the specific listening strategy involved in speech comprehension has made it difficult to determine how musicians’ higher performance in non-speech tasks contributes to their enhanced speech comprehension. The recently developed Auditory Classification Image approach reveals the precise time-frequency regions us...

  6. Mapping procedures can produce non-centered auditory images in bilateral cochlear implantees

    OpenAIRE

    Goupell, Matthew J.; Kan, Alan; Litovsky, Ruth Y.

    2013-01-01

    Good localization accuracy depends on an auditory spatial map that provides consistent binaural information across frequency and level. This study investigated whether mapping bilateral cochlear implants (CIs) independently contributes to distorted perceptual spatial maps. In a meta-analysis, interaural level differences necessary to perceptually center sound images were calculated for 127 pitch-matched pairs of electrodes; many needed large current adjustments to be perceptually centered. In...

  7. Burst firing is a neural code in an insect auditory system

    OpenAIRE

    Eyherabide, Hugo G.; Rokem, Ariel; Herz, Andreas V. M.; Samengo, Inés

    2008-01-01

    Various classes of neurons alternate between high-frequency discharges and silent intervals. This phenomenon is called burst firing. To analyze burst activity in an insect system, grasshopper auditory receptor neurons were recorded in vivo for several distinct stimulus types. The experimental data show that both burst probability and burst characteristics are strongly influenced by temporal modulations of the acoustic stimulus. The tendency to burst, hence, is not only determined by cell-intr...

  8. Perception of Auditory, Visual, and Egocentric Spatial Alignment Adapts Differently to Changes in Eye Position

    OpenAIRE

    Cui, Qi N; Razavi, Babak; O'Neill, William E.; Paige, Gary D.

    2009-01-01

    Vision and audition represent the outside world in spatial synergy that is crucial for guiding natural activities. Input conveying eye-in-head position is needed to maintain spatial congruence because the eyes move in the head while the ears remain head-fixed. Recently, we reported that the human perception of auditory space shifts with changes in eye position. In this study, we examined whether this phenomenon is 1) dependent on a visual fixation reference, 2) selective for frequency bands (...

  9. THE EFFECTS OF EXPERIMENTAL HYDROPS VERSUS INCREASED INTRACOCHLEAR PRESSURE ON AUDITORY FUNCTION IN THE GUINEA PIG

    OpenAIRE

    Horner, K; Cazals, Y.

    1990-01-01

    In order to investigate the physiological consequences of hydrops on auditory function an animal model has been developed in which endolymphatic hydrops is surgically induced and electrophysiological responses are monitored preceeding during and following hydrops induction. These studies have revealed that experimental hydrops systematically results in a fluctuant low frequency hearing loss (below 4 kHz) which is apparent within a few days of surgery. After about two months there is in additi...

  10. Increased Signal Complexity Improves the Breadth of Generalization in Auditory Perceptual Learning

    OpenAIRE

    Brown, David J.; Proulx, Michael J.

    2013-01-01

    Perceptual learning can be specific to a trained stimulus or optimally generalized to novel stimuli with the breadth of generalization being imperative for how we structure perceptual training programs. Adapting an established auditory interval discrimination paradigm to utilise complex signals, we trained human adults on a standard interval for either 2, 4, or 10 days. We then tested the standard, alternate frequency, interval, and stereo input conditions to evaluate the rapidity of specifi...

  11. Social Calls Exhibit a Distributed Consensus Map in the Auditory Cortex of Mustached Bats

    OpenAIRE

    Jagmeet S Kanwal; Ohlemiller, Kevin K.

    2012-01-01

    During echolocation in mustached bats, Pteronotus parnellii, target distance is computed from pulse-echo delays and size and velocity are computed from relative shifts in amplitude and frequency, respectively, of the pulse from the echo. Several decades of research has shown that the representation of a moving physical target at any time is distributed across multiple areas (e.g., DSCF, CF/CF and FM-FM) in the auditory cortex of mustached bats (Suga, 1984). Previous studies of call processi...

  12. Ganglioneuroma of the Internal Auditory Canal Presenting as a Vestibular Schwannoma

    OpenAIRE

    Bekelis, Kimon; Meiklejohn, Duncan A; Missios, Symeon; Harris, Brent; Saunders, James E; Erkmen, Kadir

    2011-01-01

    In most series, 90% of cerebellopontine angle tumors are vestibular schwannomas. Meningiomas and epidermoid tumors follow with decreased frequency. Ganglioneuroma is a benign tumor usually found in the retroperitoneum and posterior mediastinum. We report a case of a 21-year-old man with gradual sensorineural hearing loss and a minimally enhancing lesion of the internal auditory canal, which was excised through a middle fossa approach and found histologically to be a ganglioneuroma. Like vesti...

  13. Prestimulus frontal-parietal coherence predicts auditory detection performance in rats

    Science.gov (United States)

    Herzog, Linnea; Salehi, Kia; Bohon, Kaitlin S.

    2014-01-01

    Electrophysiology in primates has implicated long-range neural coherence as a potential mechanism for enhancing sensory detection. To test whether local synchronization and long-range neural coherence support detection performance in rats, we recorded local field potentials (LFPs) in frontal and parietal cortex while rats performed an auditory detection task. We observed significantly elevated power at multiple low frequencies (motor state. PMID:24572093

  14. Electrically evoked auditory nerve responses in the cochlea with normal outer hair cells

    OpenAIRE

    Ren, Tianying; Guo, Menghe; He, Wenxuan; Miller, Josef M.; Nuttall, Alfred L.

    2009-01-01

    As hybrid cochlear implant devices are increasingly used for restoring hearing in patients with residual hearing it is important to understand electrically evoked responses in cochleae having functional hair cells. To test the hypothesis that extracochlear electrical stimulation (EES) from sinusoidal current can provoke an auditory nerve response with normal frequency selectivity, the EES-evoked compound action potential (ECAP) was investigated in this study. Brief sinusoidal electrical curre...

  15. Stimulus Complexity and Categorical Effects in Human Auditory Cortex: An Activation Likelihood Estimation Meta-Analysis

    OpenAIRE

    Samson, Fabienne; Zeffiro, Thomas A.; Toussaint, Alain; Belin, Pascal

    2011-01-01

    Investigations of the functional organization of human auditory cortex typically examine responses to different sound categories. An alternative approach is to characterize sounds with respect to their amount of variation in the time and frequency domains (i.e., spectral and temporal complexity). Although the vast majority of published studies examine contrasts between discrete sound categories, an alternative complexity-based taxonomy can be evaluated through meta-analysis. In a quantitative...

  16. A test battery measuring auditory capabilities of listening panels

    DEFF Research Database (Denmark)

    Ghani, Jody; Ellermeier, Wolfgang; Zimmer, Karin

    2005-01-01

    battery of tests covering a larger range of auditory capabilities in order to assess individual listeners. The format of all tests is kept as 'objective' as possible by using a three-alternative forced-choice paradigm in which the subject must choose which of the sound samples is different, thus keeping...... the instruction to the subjects simple and common for all tests. Both basic (e.g. frequency discrimination) and complex (e.g. profile analysis) psychoacoustic tests are covered in the battery and a threshold of discrimination or detection is obtained for each test. Data were collected on 24 listeners...... who had been recruited for participation in an expert listening panel for evaluating the sound quality of hi-fi audio systems. The test battery data were related to the actual performance of the listeners when judging the degradation in quality produced by audio codecs....

  17. Effects of Delayed Auditory Feedback in Stuttering Patterns

    Directory of Open Access Journals (Sweden)

    Janeth Hernández Jaramillo

    2014-05-01

    Full Text Available The present study corresponds to a single subject design, analyzes the patterns of stuttering in the speech corpus in various oral language tasks, under the conditions of use or non-use of Delayed Auditory Feedback (DAF, in order to establish the effect of the DAF in the frequency of occur¬rence and type of dysrhythmia. The study concludes the positive effect of the DAF, with a rate of return of 25 % on the errors of fluency, with variation depending on the type of oral production task. This in turn suggests that 75 % of the disfluency or linked with top encode failures or not susceptible to resolve or compensated by the DAF. The authors discuss the implications of these findings for therapeutic intervention in stuttering.

  18. Assessment of visual, auditory, and kinesthetic learning style among undergraduate nursing students

    Directory of Open Access Journals (Sweden)

    Radhwan Hussein Ibrahim

    2015-12-01

    Full Text Available Background: Learning styles refer to the ability of learner to perceive and process information in learning situations. The ability to understand students’ learning styles can increase the educational outcomes. VAK (Visual, auditory, kinesthetic learning style is one of the learning style in which students use three of sensory perception to receive information. Teachers can incorporate these learning styles in their classroom activities so that students are competent to be successful in their courses. The purpose of this study is to assess Visual, Auditory, and Kinesthetic learning style among undergraduate nursing students. Methods: A descriptive study was carried out; the study was conducted during the period of 3rd. November, 2013-15, March, 2014, in two Nursing Colleges at Universities of Mosul and Kirkuk. A stratified random sampling was used for data collection. The target population was an undergraduate nursing students (210 students (60 male and 150 female. Statistical Package for the Social Science (SPSS, Chi-square, Frequencies and Percentage was used for data analysis. The results: the findings reveal that Visual, Auditory, and Kinesthetic learning style of the study sample was (40.0%, (29.5%, and 30.5% respectively. Females preferred auditory learning style (30.3% more than males (27.3%, while males preferred kinesthetic learning style (32.3% more than females (29.8%. Recommendation: The researcher recommended that nurse educators should aware of learning styles of the students and provide teaching style to be matched with their learning style.

  19. Auditory degeneration after exposure to toluene in two genotypes of mice

    Energy Technology Data Exchange (ETDEWEB)

    Li Hasheng (Karolinska Inst., Stockholm (Sweden). Dept. of Physiology 2); Johnson, A.C.; Hoeglund, G. (Karolinska Inst., Stockholm (Sweden). Dept. of Physiology 2 National Inst. of Occupational Health, Solna (Sweden). Dept. of Neuromedicine); Borg, E. (Karolinska Inst., Stockholm (Sweden). Dept. of Physiology Karolinska Hospital, Stockholm (Sweden). Dept. of Audiology Oerebro Medical Center Hospital (Sweden). Dept. of Audiology)

    1992-07-01

    Two inbred strains of mice, CBA/Ca (with a moderate hearing loss starting late in life) and C57BL/6J (with an early onset of spontaneous auditory degeneration), were exposed to toluene by inhalation (1000 ppm, 12 h/day, 7 days) at either 1 or 6 months of age. Thresholds of auditory brainstem response (ABR) were measured 3-5 days after exposure and assessed repeatedly up to the age of 16 months (C57) or 23 months (CBA). Both strains of mice exposed to toluene at 1 month of age showed a mild loss of sensitivity at a high frequency (31.5 kHz) shortly after exposure. With increasing age, toluene exposure had little effect on the aging process of the auditory system in CBA mice but accelerated age-related hearing loss in C57 mice. The results indicate that toluene exposure can aggravate auditory deterioration only in mice with a strong genetic predisposition to spontaneously precocious age-related hearing loss. (orig.).

  20. 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.

  1. Visceral hyperalgesia induced by forebrain-specific suppression of native Kv7/KCNQ/M-current in mice

    Directory of Open Access Journals (Sweden)

    Bian Xiling

    2011-10-01

    Full Text Available Abstract Background Dysfunction of brain-gut interaction is thought to underlie visceral hypersensitivity which causes unexplained abdominal pain syndromes. However, the mechanism by which alteration of brain function in the brain-gut axis influences the perception of visceral pain remains largely elusive. In this study we investigated whether altered brain activity can generate visceral hyperalgesia. Results Using a forebrain specific αCaMKII promoter, we established a line of transgenic (Tg mice expressing a dominant-negative pore mutant of the Kv7.2/KCNQ2 channel which suppresses native KCNQ/M-current and enhances forebrain neuronal excitability. Brain slice recording of hippocampal pyramidal neurons from these Tg mice confirmed the presence of hyperexcitable properties with increased firing. Behavioral evaluation of Tg mice exhibited increased sensitivity to visceral pain induced by intraperitoneal (i.p. injection of either acetic acid or magnesium sulfate, and intracolon capsaicin stimulation, but not cutaneous sensation for thermal or inflammatory pain. Immunohistological staining showed increased c-Fos expression in the somatosensory SII cortex and insular cortex of Tg mice that were injected intraperitoneally with acetic acid. To mimic the effect of cortical hyperexcitability on visceral hyperalgesia, we injected KCNQ/M channel blocker XE991 into the lateral ventricle of wild type (WT mice. Intracerebroventricular injection of XE991 resulted in increased writhes of WT mice induced by acetic acid, and this effect was reversed by co-injection of the channel opener retigabine. Conclusions Our findings provide evidence that forebrain hyperexcitability confers visceral hyperalgesia, and suppression of central hyperexcitability by activation of KCNQ/M-channel function may provide a therapeutic potential for treatment of abdominal pain syndromes.

  2. Transgenic up-regulation of alpha-CaMKII in forebrain leads to increased anxiety-like behaviors and aggression

    Directory of Open Access Journals (Sweden)

    Hasegawa Shunsuke

    2009-03-01

    Full Text Available Abstract Background Previous studies have demonstrated essential roles for alpha-calcium/calmodulin-dependent protein kinase II (alpha-CaMKII in learning, memory and long-term potentiation (LTP. However, previous studies have also shown that alpha-CaMKII (+/- heterozygous knockout mice display a dramatic decrease in anxiety-like and fearful behaviors, and an increase in defensive aggression. These findings indicated that alpha-CaMKII is important not only for learning and memory but also for emotional behaviors. In this study, to understand the roles of alpha-CaMKII in emotional behavior, we generated transgenic mice overexpressing alpha-CaMKII in the forebrain and analyzed their behavioral phenotypes. Results We generated transgenic mice overexpressing alpha-CaMKII in the forebrain under the control of the alpha-CaMKII promoter. In contrast to alpha-CaMKII (+/- heterozygous knockout mice, alpha-CaMKII overexpressing mice display an increase in anxiety-like behaviors in open field, elevated zero maze, light-dark transition and social interaction tests, and a decrease in locomotor activity in their home cages and novel environments; these phenotypes were the opposite to those observed in alpha-CaMKII (+/- heterozygous knockout mice. In addition, similarly with alpha-CaMKII (+/- heterozygous knockout mice, alpha-CaMKII overexpressing mice display an increase in aggression. However, in contrast to the increase in defensive aggression observed in alpha-CaMKII (+/- heterozygous knockout mice, alpha-CaMKII overexpressing mice display an increase in offensive aggression. Conclusion Up-regulation of alpha-CaMKII expression in the forebrain leads to an increase in anxiety-like behaviors and offensive aggression. From the comparisons with previous findings, we suggest that the expression levels of alpha-CaMKII are associated with the state of emotion; the expression level of alpha-CaMKII positively correlates with the anxiety state and strongly affects

  3. Reduced brain perfusion in basal forebrain associated with cognitive decline in Alzheimer's diseases: a Tc-99m HMPAO SPECT study

    International Nuclear Information System (INIS)

    Aim: Reduction of regional cerebral blood flow (rCBF) in various cerebral regions and decline of cognitive function have been reported in Alzheimer's disease (AD) patients. The aim of this study was to identify the brain areas showing correlation between longitudinal changes of rCBFs and decline of general mental function, measured by Mini-Mental State Examination (MMSE) in probable Alzheimer's disease patients. Materials and Methods: Nine probable AD patients according to NINCDS-ADRDA criteria and DSM-IV were studied with Tc-99m HMPAO SPECT at an initial point and at the follow-up after a period of average 1.8 year. MMSE score was obtained in both occasions (average MMSE 16.4 at initial study; average MMSE = 8.1 at follow-up). Single SPECT was performed in 30 age-matched normal controls. Each SPECT image was normalized to the cerebellar activity. Using statistical parametric mapping (SPM99), correlation was analyzed between individual changes in rCBF of two SPECT scans and the MMSE scores at the time of each study in AD patients. In addition, the SPECT images of the initial study and the follow-up study were compared with SPECT images of the age-matched normal group respectively. Results: Significant correlation between longitudinal changes of rCBFs and MMSE scores was found in left basal forebrain region including substantia innominata (x, y, z = -24, 16, -23; P < .05, corrected). Within a short follow-up period of 1.8 years, cerebral hypoperfusion extended to various cortical regions from bilateral temporo-parietal to bilateral frontal regions and cingulate cortex, compared to normal controls. Conclusion: The decline of cognitive function in individual AD patients was correlated with rCBF reduction in left basal forebrain. This finding supports the cholinergic hypothesis of AD since hypoperfusion in basal forebrain region might indicate deterioration of cholinergic neurons in nucleus basalis of Meynert or substantia innominata

  4. Long-term delivery of nerve growth factor by encapsulated cell biodelivery in the Göttingen minipig basal forebrain

    DEFF Research Database (Denmark)

    Fjord-Larsen, L; Kusk, P; Tornøe, Jens;

    2010-01-01

    , capable of local delivery of NGF. The clinical device, named NsG0202, houses an NGF-secreting cell line (NGC-0295), which is derived from a human retinal pigment epithelial (RPE) cell line, stably genetically modified to secrete NGF. Bioactivity and correct processing of NGF was confirmed in vitro. Ns......G0202 devices were implanted in the basal forebrain of Göttingen minipigs and the function and retrievability were evaluated after 7 weeks, 6 and 12 months. All devices were implanted and retrieved without associated complications. They were physically intact and contained a high number of viable and...

  5. Evidence that bovine forebrain embryonic zinc finger-like gene influences immune response associated with mastitis resistance

    OpenAIRE

    Sugimoto, Mayumi; Fujikawa, Akira; Womack, James E.; Sugimoto, Yoshikazu

    2006-01-01

    Mastitis, a mammary gland inflammation in response to bacterial infection, is a major problem in the dairy industry. We found that cows susceptible to mastitis have a three-base insertion in a glycine-coding stretch of the gene for forebrain embryonic zinc finger-like (FEZL), a transcription factor with a role in neuronal development. Mastitis induces FEZL expression in mammary glands, and induced FEZL promotes expression of the axon-attracting molecule semaphorin 5A (SEMA5A) through a GCAG s...

  6. Alterations in subcellular expression of acid-sensing ion channels in the rat forebrain following chronic amphetamine administration

    OpenAIRE

    Suman, Ajay; Mehta, Bhavi; Guo, Ming-Lei; Chu, Xiang-Ping; Fibuch, Eugene E.; Mao, Li-Min; WANG, John Q.

    2010-01-01

    Acid-sensing ion channels (ASICs) are densely expressed in broad areas of mammalian brains and actively modulate synaptic transmission and a variety of neuronal activities. To explore whether ASICs are linked to addictive properties of drugs of abuse, we investigated the effect of the psychostimulant amphetamine on subcellular ASIC expression in the rat forebrain in vivo. Repeated administration of amphetamine (once daily for 7 days, 1.25 mg/kg for days 1/7, 4 mg/kg for days 2–6) induced typi...

  7. The behavioral impact of auditory and visual oddball distracters in a visual and auditory categorization tasks

    OpenAIRE

    Alicia Leiva

    2011-01-01

    Past cross-modal oddball studies have shown that participants respond slower to visual targets following the presentation of an unexpected change in a stream of auditory distracters. In the present study we examined the extent to which this novelty distraction may transcend the sensory distinction between distracter and target. In separate blocks of trials, participants categorized digits presented auditorily or visually in the face of visual or auditory standard and oddball distracters. The ...

  8. Reading adn Auditory-Visual Equivalences

    Science.gov (United States)

    Sidman, Murray

    1971-01-01

    A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…

  9. The Goldilocks Effect in Infant Auditory Attention

    Science.gov (United States)

    Kidd, Celeste; Piantadosi, Steven T.; Aslin, Richard N.

    2014-01-01

    Infants must learn about many cognitive domains (e.g., language, music) from auditory statistics, yet capacity limits on their cognitive resources restrict the quantity that they can encode. Previous research has established that infants can attend to only a subset of available acoustic input. Yet few previous studies have directly examined infant…

  10. Development of Receiver Stimulator for Auditory Prosthesis

    Directory of Open Access Journals (Sweden)

    K. Raja Kumar

    2010-05-01

    Full Text Available The Auditory Prosthesis (AP is an electronic device that can provide hearing sensations to people who are profoundly deaf by stimulating the auditory nerve via an array of electrodes with an electric current allowing them to understand the speech. The AP system consists of two hardware functional units such as Body Worn Speech Processor (BWSP and Receiver Stimulator. The prototype model of Receiver Stimulator for Auditory Prosthesis (RSAP consists of Speech Data Decoder, DAC, ADC, constant current generator, electrode selection logic, switch matrix and simulated electrode resistance array. The laboratory model of speech processor is designed to implement the Continuous Interleaved Sampling (CIS speech processing algorithm which generates the information required for electrode stimulation based on the speech / audio data. Speech Data Decoder receives the encoded speech data via an inductive RF transcutaneous link from speech processor. Twelve channels of auditory Prosthesis with selectable eight electrodes for stimulation of simulated electrode resistance array are used for testing. The RSAP is validated by using the test data generated by the laboratory prototype of speech processor. The experimental results are obtained from specific speech/sound tests using a high-speed data acquisition system and found satisfactory.

  11. Preferred levels of auditory danger signals.

    Science.gov (United States)

    Zera, J; Nagórski, A

    2000-01-01

    An important issue at the design stage of the auditory danger signal for a safety system is the signal audibility under various conditions of background noise. The auditory danger signal should be clearly audible but it should not be too loud to avoid fright, startling effects, and nuisance complaints. Criteria for designing auditory danger signals are the subject of the ISO 7731 (International Organization for Standardization [ISO], 1986) international standard and the EN 457 European standard (European Committee for Standardization [CEN], 1992). It is required that the A-weighted sound pressure level of the auditory danger signal is higher in level than the background noise by 15 dB. In this paper, the results of an experiment are reported, in which listeners adjusted most preferred levels of 3 danger signals (tone, sweep, complex sound) in the presence of a noise background (pink noise and industrial noise). The measurements were done for 60-, 70-, 80-, and 90-dB A-weighted levels of noise. Results show that for 60-dB level of noise the most preferred level of the danger signal is 10 to 20 dB above the noise level. However, for 90-dB level of noise, listeners selected a level of the danger signal that was equal to the noise level. Results imply that the criterion in the existing standards is conservative as it requires the level of the danger signal to be higher than the level of noise regardless of the noise level. PMID:10828157

  12. Lateralization of auditory-cortex functions.

    Science.gov (United States)

    Tervaniemi, Mari; Hugdahl, Kenneth

    2003-12-01

    In the present review, we summarize the most recent findings and current views about the structural and functional basis of human brain lateralization in the auditory modality. Main emphasis is given to hemodynamic and electromagnetic data of healthy adult participants with regard to music- vs. speech-sound encoding. Moreover, a selective set of behavioral dichotic-listening (DL) results and clinical findings (e.g., schizophrenia, dyslexia) are included. It is shown that human brain has a strong predisposition to process speech sounds in the left and music sounds in the right auditory cortex in the temporal lobe. Up to great extent, an auditory area located at the posterior end of the temporal lobe (called planum temporale [PT]) underlies this functional asymmetry. However, the predisposition is not bound to informational sound content but to rapid temporal information more common in speech than in music sounds. Finally, we obtain evidence for the vulnerability of the functional specialization of sound processing. These altered forms of lateralization may be caused by top-down and bottom-up effects inter- and intraindividually In other words, relatively small changes in acoustic sound features or in their familiarity may modify the degree in which the left vs. right auditory areas contribute to sound encoding. PMID:14629926

  13. Self-affirmation in auditory persuasion

    NARCIS (Netherlands)

    Elbert, Sarah; Dijkstra, Arie

    2011-01-01

    Persuasive health information can be presented through an auditory channel. Curiously enough, the effect of voice cues in health persuasion has hardly been studied. Research concerning visual persuasive messages showed that self-affirmation results in a more open-minded reaction to threatening infor

  14. Late Maturation of Auditory Perceptual Learning

    Science.gov (United States)

    Huyck, Julia Jones; Wright, Beverly A.

    2011-01-01

    Adults can improve their performance on many perceptual tasks with training, but when does the response to training become mature? To investigate this question, we trained 11-year-olds, 14-year-olds and adults on a basic auditory task (temporal-interval discrimination) using a multiple-session training regimen known to be effective for adults. The…

  15. Affective priming with auditory speech stimuli

    NARCIS (Netherlands)

    J. Degner

    2011-01-01

    Four experiments explored the applicability of auditory stimulus presentation in affective priming tasks. In Experiment 1, it was found that standard affective priming effects occur when prime and target words are presented simultaneously via headphones similar to a dichotic listening procedure. In

  16. Integration and segregation in auditory scene analysis

    Science.gov (United States)

    Sussman, Elyse S.

    2005-03-01

    Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

  17. Auditory confrontation naming in Alzheimer's disease.

    Science.gov (United States)

    Brandt, Jason; Bakker, Arnold; Maroof, David Aaron

    2010-11-01

    Naming is a fundamental aspect of language and is virtually always assessed with visual confrontation tests. Tests of the ability to name objects by their characteristic sounds would be particularly useful in the assessment of visually impaired patients, and may be particularly sensitive in Alzheimer's disease (AD). We developed an auditory naming task, requiring the identification of the source of environmental sounds (i.e., animal calls, musical instruments, vehicles) and multiple-choice recognition of those not identified. In two separate studies mild-to-moderate AD patients performed more poorly than cognitively normal elderly on the auditory naming task. This task was also more difficult than two versions of a comparable visual naming task, and correlated more highly with Mini-Mental State Exam score. Internal consistency reliability was acceptable, although ROC analysis revealed auditory naming to be slightly less successful than visual confrontation naming in discriminating AD patients from normal participants. Nonetheless, our auditory naming task may prove useful in research and clinical practice, especially with visually impaired patients. PMID:20981630

  18. Auditory risk estimates for youth target shooting

    Science.gov (United States)

    Meinke, Deanna K.; Murphy, William J.; Finan, Donald S.; Lankford, James E.; Flamme, Gregory A.; Stewart, Michael; Soendergaard, Jacob; Jerome, Trevor W.

    2015-01-01

    Objective To characterize the impulse noise exposure and auditory risk for youth recreational firearm users engaged in outdoor target shooting events. The youth shooting positions are typically standing or sitting at a table, which places the firearm closer to the ground or reflective surface when compared to adult shooters. Design Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit suggested by the World Health Organization (1999) for children. Study sample Impulses were generated by 26 firearm/ammunition configurations representing rifles, shotguns, and pistols used by youth. Measurements were obtained relative to a youth shooter’s left ear. Results All firearms generated peak levels that exceeded the 120 dB peak limit suggested by the WHO for children. In general, shooting from the seated position over a tabletop increases the peak levels, LAeq8 and reduces the unprotected maximum permissible exposures (MPEs) for both rifles and pistols. Pistols pose the greatest auditory risk when fired over a tabletop. Conclusion Youth should utilize smaller caliber weapons, preferably from the standing position, and always wear hearing protection whenever engaging in shooting activities to reduce the risk for auditory damage. PMID:24564688

  19. Biological impact of auditory expertise across the life span: musicians as a model of auditory learning.

    Science.gov (United States)

    Strait, Dana L; Kraus, Nina

    2014-02-01

    Experience-dependent characteristics of auditory function, especially with regard to speech-evoked auditory neurophysiology, have garnered increasing attention in recent years. This interest stems from both pragmatic and theoretical concerns as it bears implications for the prevention and remediation of language-based learning impairment in addition to providing insight into mechanisms engendering experience-dependent changes in human sensory function. Musicians provide an attractive model for studying the experience-dependency of auditory processing in humans due to their distinctive neural enhancements compared to nonmusicians. We have only recently begun to address whether these enhancements are observable early in life, during the initial years of music training when the auditory system is under rapid development, as well as later in life, after the onset of the aging process. Here we review neural enhancements in musically trained individuals across the life span in the context of cellular mechanisms that underlie learning, identified in animal models. Musicians' subcortical physiologic enhancements are interpreted according to a cognitive framework for auditory learning, providing a model in which to study mechanisms of experience-dependent changes in human auditory function. PMID:23988583

  20. McGurk illusion recalibrates subsequent auditory perception.

    Science.gov (United States)

    Lüttke, Claudia S; Ekman, Matthias; van Gerven, Marcel A J; de Lange, Floris P

    2016-01-01

    Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of 'ada'. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we asked whether the altered auditory perception due to the McGurk illusion affects subsequent auditory perception, i.e. whether this process of fusion may cause a recalibration of the auditory boundaries between phonemes. Participants categorized auditory and audiovisual speech stimuli as /aba/, /ada/ or /aga/ while activity patterns in their auditory cortices were recorded using fMRI. Interestingly, following a McGurk illusion, an auditory /aba/ was more often misperceived as 'ada'. Furthermore, we observed a neural counterpart of this recalibration in the early auditory cortex. When the auditory input /aba/ was perceived as 'ada', activity patterns bore stronger resemblance to activity patterns elicited by /ada/ sounds than when they were correctly perceived as /aba/. Our results suggest that upon experiencing the McGurk illusion, the brain shifts the neural representation of an /aba/ sound towards /ada/, culminating in a recalibration in perception of subsequent auditory input. PMID:27611960

  1. Characterization of auditory synaptic inputs to gerbil perirhinal cortex

    Directory of Open Access Journals (Sweden)

    Vibhakar C Kotak

    2015-08-01

    Full Text Available The representation of acoustic cues involves regions downstream from the auditory cortex (ACx. One such area, the perirhinal cortex (PRh, processes sensory signals containing mnemonic information. Therefore, our goal was to assess whether PRh receives auditory inputs from the auditory thalamus (MG and ACx in an auditory thalamocortical brain slice preparation and characterize these afferent-driven synaptic properties. When the MG or ACx was electrically stimulated, synaptic responses were recorded from the PRh neurons. Blockade of GABA-A receptors dramatically increased the amplitude of evoked excitatory potentials. Stimulation of the MG or ACx also evoked calcium transients in most PRh neurons. Separately, when fluoro ruby was injected in ACx in vivo, anterogradely labeled axons and terminals were observed in the PRh. Collectively, these data show that the PRh integrates auditory information from the MG and ACx and that auditory driven inhibition dominates the postsynaptic responses in a non-sensory cortical region downstream from the auditory cortex.

  2. Patterned Tone Sequences Reveal Non-Linear Interactions in Auditory Spectrotemporal Receptive Fields in the Inferior Colliculus

    OpenAIRE

    BRIMIJOIN, W. OWEN; O'Neill, William E.

    2010-01-01

    Linear measures of auditory receptive fields do not always fully account for a neuron's response to spectrotemporally-complex signals such as frequency-modulated sweeps (FM) and communication sounds. A possible source of this discrepancy is cross-frequency interactions, common response properties which may be missed by linear receptive fields but captured using two-tone masking. Using a patterned tonal sequence that included a balanced set of all possible tone-to-tone transitions, we have her...

  3. Listening to tailor-made notched music reduces tinnitus loudness and tinnitus-related auditory cortex activity

    OpenAIRE

    Okamoto, Hidehiko; Stracke, Henning; Stoll, Wolfgang; Pantev, Christo

    2009-01-01

    Maladaptive auditory cortex reorganization may contribute to the generation and maintenance of tinnitus. Because cortical organization can be modified by behavioral training, we attempted to reduce tinnitus loudness by exposing chronic tinnitus patients to self-chosen, enjoyable music, which was modified (“notched”) to contain no energy in the frequency range surrounding the individual tinnitus frequency. After 12 months of regular listening, the target patient group (n = 8) showed significan...

  4. Prediction of hearing thresholds: Comparison of cortical evoked response audiometry and auditory steady state response audiometry techniques

    OpenAIRE

    Wong, LLN; Yeung, KNK

    2007-01-01

    The present study evaluated how well auditory steady state response (ASSR) and tone burst cortical evoked response audiometry (CERA) thresholds predict behavioral thresholds in the same participants. A total of 63 ears were evaluated. For ASSR testing, 100% amplitude modulated and 10% frequency modulated tone stimuli at a modulation frequency of 40Hz were used. Behavioral thresholds were closer to CERA thresholds than ASSR thresholds. ASSR and CERA thresholds were closer to behavioral thresho...

  5. The Essential Complexity of Auditory Receptive Fields.

    Science.gov (United States)

    Thorson, Ivar L; Liénard, Jean; David, Stephen V

    2015-12-01

    Encoding properties of sensory neurons are commonly modeled using linear finite impulse response (FIR) filters. For the auditory system, the FIR filter is instantiated in the spectro-temporal receptive field (STRF), often in the framework of the generalized linear model. Despite widespread use of the FIR STRF, numerous formulations for linear filters are possible that require many fewer parameters, potentially permitting more efficient and accurate model estimates. To explore these alternative STRF architectures, we recorded single-unit neural activity from auditory cortex of awake ferrets during presentation of natural sound stimuli. We compared performance of > 1000 linear STRF architectures, evaluating their ability to predict neural responses to a novel natural stimulus. Many were able to outperform the FIR filter. Two basic constraints on the architecture lead to the improved performance: (1) factorization of the STRF matrix into a small number of spectral and temporal filters and (2) low-dimensional parameterization of the factorized filters. The best parameterized model was able to outperform the full FIR filter in both primary and secondary auditory cortex, despite requiring fewer than 30 parameters, about 10% of the number required by the FIR filter. After accounting for noise from finite data sampling, these STRFs were able to explain an average of 40% of A1 response variance. The simpler models permitted more straightforward interpretation of sensory tuning properties. They also showed greater benefit from incorporating nonlinear terms, such as short term plasticity, that provide theoretical advances over the linear model. Architectures that minimize parameter count while maintaining maximum predictive power provide insight into the essential degrees of freedom governing auditory cortical function. They also maximize statistical power available for characterizing additional nonlinear properties that limit current auditory models. PMID:26683490

  6. Cytotoxicity of synthetic cannabinoids on primary neuronal cells of the forebrain: the involvement of cannabinoid CB{sub 1} receptors and apoptotic cell death

    Energy Technology Data Exchange (ETDEWEB)

    Tomiyama, Ken-ichi; Funada, Masahiko, E-mail: mfunada@ncnp.go.jp

    2014-01-01

    The abuse of herbal products containing synthetic cannabinoids has become an issue of public concern. The purpose of this paper was to evaluate the acute cytotoxicity of synthetic cannabinoids on mouse brain neuronal cells. Cytotoxicity induced by synthetic cannabinoid (CP-55,940, CP-47,497, CP-47,497-C8, HU-210, JWH-018, JWH-210, AM-2201, and MAM-2201) was examined using forebrain neuronal cultures. These synthetic cannabinoids induced cytotoxicity in the forebrain cultures in a concentration-dependent manner. The cytotoxicity was suppressed by preincubation with the selective CB{sub 1} receptor antagonist AM251, but not with the selective CB{sub 2} receptor antagonist AM630. Furthermore, annexin-V-positive cells were found among the treated forebrain cells. Synthetic cannabinoid treatment induced the activation of caspase-3, and preincubation with a caspase-3 inhibitor significantly suppressed the cytotoxicity. These synthetic cannabinoids induced apoptosis through a caspase-3-dependent mechanism in the forebrain cultures. Our results indicate that the cytotoxicity of synthetic cannabinoids towards primary neuronal cells is mediated by the CB{sub 1} receptor, but not by the CB{sub 2} receptor, and further suggest that caspase cascades may play an important role in the apoptosis induced by these synthetic cannabinoids. In conclusion, excessive synthetic cannabinoid abuse may present a serious acute health concern due to neuronal damage or deficits in the brain. - Highlights: • Synthetic cannabinoids (classical cannabinoids, non-classical cannabinoids, and aminoalkylindole derivatives) induce cytotoxicity in mouse forebrain cultures. • Synthetic cannabinoid-induced cytotoxicity towards forebrain cultures is mediated by the CB{sub 1} receptor, but not by the CB{sub 2} receptor, and involves caspase-dependent apoptosis. • A high concentration of synthetic cannabinoids may be toxic to neuronal cells that express CB{sub 1} receptors.

  7. Cytotoxicity of synthetic cannabinoids on primary neuronal cells of the forebrain: the involvement of cannabinoid CB1 receptors and apoptotic cell death

    International Nuclear Information System (INIS)

    The abuse of herbal products containing synthetic cannabinoids has become an issue of public concern. The purpose of this paper was to evaluate the acute cytotoxicity of synthetic cannabinoids on mouse brain neuronal cells. Cytotoxicity induced by synthetic cannabinoid (CP-55,940, CP-47,497, CP-47,497-C8, HU-210, JWH-018, JWH-210, AM-2201, and MAM-2201) was examined using forebrain neuronal cultures. These synthetic cannabinoids induced cytotoxicity in the forebrain cultures in a concentration-dependent manner. The cytotoxicity was suppressed by preincubation with the selective CB1 receptor antagonist AM251, but not with the selective CB2 receptor antagonist AM630. Furthermore, annexin-V-positive cells were found among the treated forebrain cells. Synthetic cannabinoid treatment induced the activation of caspase-3, and preincubation with a caspase-3 inhibitor significantly suppressed the cytotoxicity. These synthetic cannabinoids induced apoptosis through a caspase-3-dependent mechanism in the forebrain cultures. Our results indicate that the cytotoxicity of synthetic cannabinoids towards primary neuronal cells is mediated by the CB1 receptor, but not by the CB2 receptor, and further suggest that caspase cascades may play an important role in the apoptosis induced by these synthetic cannabinoids. In conclusion, excessive synthetic cannabinoid abuse may present a serious acute health concern due to neuronal damage or deficits in the brain. - Highlights: • Synthetic cannabinoids (classical cannabinoids, non-classical cannabinoids, and aminoalkylindole derivatives) induce cytotoxicity in mouse forebrain cultures. • Synthetic cannabinoid-induced cytotoxicity towards forebrain cultures is mediated by the CB1 receptor, but not by the CB2 receptor, and involves caspase-dependent apoptosis. • A high concentration of synthetic cannabinoids may be toxic to neuronal cells that express CB1 receptors

  8. Brian hears: online auditory processing using vectorisation over channels

    Directory of Open Access Journals (Sweden)

    Bertrand eFontaine

    2011-07-01

    Full Text Available The human cochlea includes about 3000 inner hair cells which filter sounds at frequencies between 20 Hz and 20 kHz. This massively parallel frequency analysis is reflected in models of auditory processing, which are often based on banks of filters. However, existing implementations do not exploit this parallelism. Here we propose algorithms to simulate these models by vectorising computation over frequency channels, which are implemented in Brian Hears, a library for the spiking neural network simulator package Brian. This approach allows us to use high-level programming languages such as Python, as the cost of interpretation becomes negligible. This makes it possible to define and simulate complex models in a simple way, while all previous implementations were model-specific. In addition, we show that these algorithms can be naturally parallelised using graphics processing units, yielding substantial speed improvements. We demonstrate these algorithms with several state-of-the-art cochlear models, and show that they compare favorably with existing, less flexible, implementations.

  9. [Novel calretinin-positive cells with polymorphous spines in the mouse forebrain during early postnatal ontogenesis].

    Science.gov (United States)

    Revishchin, A V; Okhotin, V E; Pavlova, G V

    2009-01-01

    Using an immunocytochemical method for calretinin (CR) detection, we have earlier described (Morfologiya, 2009 v. 135. No. 3, p. 7-19) the population of previously unknown mono- and bipolar cells with polymorphous spines (PS) covering their cell bodies and processes, in adult mice forebrain structures adjacent to anterior horn of lateral ventricle. CR-positive spiny (CR+PS) cells were negative to GAD67 and were detected in the white matter and in layers V and VI of frontal area of dorsomedial cortex close to the cingulum, in in rostro-dorsal part of the caudate nucleus-putamen complex, anterior olfactory nucleus and in subependymal layer of the dorso-lateral angle of the lateral ventricle. In this work, the distribution of these cells in 7-day-old mice was studied. Comparative topographical analysis of definitive and early CR+PS cells demonstrated that in 7-day-old mice CR+PS cells were absent from the areas of their localization in adult animals - anterior olfactory nucleus, cortical plate and inner portion of neostriatum. Meanwhile, some CR+PS-like cells were detected in 7-day-old mice inside the rostral migratory route, close to neostriatum anterior boundary, along the dorsal border between neostriatum and corpus callosum, subependymal layer of lateral wall of the lateral ventricle, and in the cingulum area. These findings are indicative of the possible postnatal appearance of CR+PS cells. To test this hypothesis, the experiments were conducted in which bromodeoxyuridine (BrdU) was administered to the mice on their postnatal days 2-4 with the subsequent study of the brain sections of these animals sacrificed on their postnatal day 20. Double immunolabeling of these sections for CR and BrdU has detected the presence of CR+PS cells that contained postnatally administered BrdU. These results strongly suggest that, at least, some portion of CR+PS cells have their mitosis postnatally. It may be assumed, that CR+PS cells migrate to the sites of their distribution in

  10. New calretinin-positive cells with polymorphous spines in the mouse forebrain during early postnatal ontogeny.

    Science.gov (United States)

    Revishchin, A V; Okhotin, V E; Pavlova, G V

    2010-10-01

    Immunohistochemical studies of calretinin (CR) in forebrain structures adjacent to the anterior horn of the lateral ventricle in adult mice allowed us to detect a population of previously unknown mono- and bipolar cells whose bodies and processes were coated with polymorphous spines (PS) (Morfologiya, 135, No. 3, 7-19 (2009)). CR-positive spiny (CR(+)PS) cells did not contain GAD67 and were located in the white matter and layers V-VI of the frontal area of the dorsomedial cortex close to the cingulum, the rostrodorsal part of the caudate-putamen, the anterior olfactory nucleus, and the subependyma of the dorsolateral angle of the lateral ventricle. We report here studies of the distribution of these cells in seven-day-old mice. Comparative topographic analysis of definitive and early CR(+)PS cells showed that in seven-day-old mice, CR(+)PS cells were absent from the sites at which they were seen in adults, i.e., the anterior olfactory cortex, the cortical plate, and the inner part of the neostriatum. In addition, small numbers of CR(+)PS-like cells were seen at this age within the dorsal migration pathway, at the anterior margin of the neostriatum, along the dorsal border of the neostriatum with the corpus callosum, in the subependymal layer of the lateral wall of the lateral ventricle, and in the cingulum area. These data demonstrate that CR(+)PS cells may have a postnatal origin. Experiments to verify this hypothesis were performed using postnatal administration of bromodeoxyuridine (BrdU) to mice aged 2-4 days, followed by assessment of brain sections fixed at age 20 days. Double immunolabeling of sections for CR and BrdU demonstrated the presence of CR(+)PS cells containing postnatally supplied BrdU. These data provide evidence that at least some CR(+)PS cells undergo mitosis at postnatal age. In all probability, during the period from 7 to 20 days of postnatal development, CR(+)PS cells migrate to the sites that they occupy in adult animals. PMID:20721693

  11. Time-lapse imaging of neuroblast migration in acute slices of the adult mouse forebrain.

    Science.gov (United States)

    Khlghatyan, Jivan; Saghatelyan, Armen

    2012-01-01

    the stationary and migratory phases is crucial for the unambiguous interpretation of results. We also performed multiple z-step acquisitions to monitor neuroblasts migration in 3D. Wide-field fluorescent imaging has been used extensively to visualize neuronal migration. Here, we describe detailed protocol for labeling neuroblasts, performing real-time video-imaging of neuroblast migration in acute slices of the adult mouse forebrain, and analyzing cell migration. While the described protocol exemplified the migration of neuroblasts in the adult RMS, it can also be used to follow cell migration in embryonic and early postnatal brains. PMID:23007608

  12. Auralization of CFD Vorticity Using an Auditory Illusion

    Science.gov (United States)

    Volpe, C. R.

    2005-12-01

    , the simple approach of mapping clockwise and counterclockwise rotations to actual pitch increases and decreases, eventually results in sounds that the listener cannot hear. In this alternate presentation using an auditory illusion, repeated rotations of a stream-tube are replaced with continual increases or decreases in apparent pitch. These apparent pitch changes can continue without bound, yet never exceed the range of frequencies that the listener can hear. The effectiveness of this presentation technique has been studied, and empirical results, obtained through formal user testing and statistical analysis, are presented. These results demonstrate that an aural data presentation using an auditory illusion can improve performance in locating key data characteristics, a task that demonstrates a certain level of understanding of the data. The experiments show that this holds true even when the user expresses a subjective preference and greater confidence in a visual presentation. The CFD data used in the research comes from a number of different industrial domains, but the advantages of this technique could be equally applicable to the study of earth sciences involving fluid mechanics, such as atmospheric or ocean sciences. Furthermore, the approach is applicable not only to CFD data, but to any type of data in which a quantity that is cyclic in nature, such as orientation, needs to be presented. Although the techniques and tools were originally developed with scientists and engineers in mind, they can also be used to aid students, particularly those who are visually impaired or who have difficulty interpreting certain spatial relationships visually.

  13. Relationship between the anterior forebrain mesocircuit and the default mode network in the structural bases of disorders of consciousness

    Directory of Open Access Journals (Sweden)

    Nicholas D. Lant

    2016-01-01

    Full Text Available The specific neural bases of disorders of consciousness (DOC are still not well understood. Some studies have suggested that functional and structural impairments in the default mode network may play a role in explaining these disorders. In contrast, others have proposed that dysfunctions in the anterior forebrain mesocircuit involving striatum, globus pallidus, and thalamus may be the main underlying mechanism. Here, we provide the first report of structural integrity of fiber tracts connecting the nodes of the mesocircuit and the default mode network in 8 patients with DOC. We found evidence of significant damage to subcortico-cortical and cortico-cortical fibers, which were more severe in vegetative state patients and correlated with clinical severity as determined by Coma Recovery Scale—Revised (CRS-R scores. In contrast, fiber tracts interconnecting subcortical nodes were not significantly impaired. Lastly, we found significant damage in all fiber tracts connecting the precuneus with cortical and subcortical areas. Our results suggest a strong relationship between the default mode network – and most importantly the precuneus – and the anterior forebrain mesocircuit in the neural basis of the DOC.

  14. Distribution of 125I-neurotensin binding sites in human forebrain: Comparison with the localization of acetylcholinesterase

    International Nuclear Information System (INIS)

    The distribution of 125I-neurotensin binding sites was compared with that of acetylcholinesterase reactivity in the human basal forebrain by using combined light microscopic radioautography/histochemistry. High 125I-neurotensin binding densities were observed in the bed nucleus of the stria terminalis, islands of Calleja, claustrum, olfactory tubercle, and central nucleus of the amygdala; lower levels were seen in the caudate, putamen, medial septum, diagonal band nucleus, and nucleus basalis of Meynert. Adjacent sections processed for cholinesterase histochemistry demonstrated a regional overlap between the distribution of labeled neurotensin binding sites and that of intense acetylcholinesterase staining in all of the above regions, except in the bed nucleus of the stria terminalis, claustrum, and central amygdaloid nucleus, where dense 125I-neurotensin labeling was detected over areas containing only weak to moderate cholinesterase staining. At higher magnification, 125I-neurotensin-labeled binding sites in the islands of Calleja, supraoptic nucleus of the hypothalamus, medial septum, diagonal band nucleus, and nucleus basalis of Meynert were selectively associated with neuronal perikarya found to be cholinesterase-positive in adjacent sections. Moderate 125I-neurotensin binding was also apparent over the cholinesterase-reactive neuropil of these latter three regions. These data suggest that neurotensin (NT) may directly influence the activity of magnocellular cholinergic neurons in the human basal forebrain, and may be involved in the physiopathology of dementing disorders such as Alzheimer's disease, in which these neurons have been shown to be affected

  15. Genome-wide analysis of epigenomic alterations in fetal mouse forebrain after exposure to low doses of bisphenol A.

    Science.gov (United States)

    Yaoi, Takeshi; Itoh, Kyoko; Nakamura, Keiko; Ogi, Hiroshi; Fujiwara, Yasuhiro; Fushiki, Shinji

    2008-11-21

    Bisphenol A (BPA) is one of endocrine disrupting chemicals, being distributed widely in the environment. We have been studying the low dose effects of BPA on murine forebrain development. Here, we have investigated the genome-wide effect of maternal exposure to BPA on the epigenome in mouse forebrain at E12.5 and at E14.5. We scanned CpG methylation status in 2500 NotI loci, representing 48 (de)methylated unique loci. Methylation status in most of them was primarily developmental stage-dependent. Each of almost all cloned NotI loci was located in a CpG island (CGI) adjacent to 5' end of the transcriptional unit. The mRNA expression of two functionally related genes changed with development as well as the exposure to BPA. In both genes, changes at the transcriptional level correlated well with the changes in NotI methylation status. Taken together, epigenetic alterations in promoter-associated CGIs after exposure to BPA may underlie some effects on brain development. PMID:18804091

  16. EEG phase reset due to auditory attention: an inverse time-scale approach

    International Nuclear Information System (INIS)

    We propose a novel tool to evaluate the electroencephalograph (EEG) phase reset due to auditory attention by utilizing an inverse analysis of the instantaneous phase for the first time. EEGs were acquired through auditory attention experiments with a maximum entropy stimulation paradigm. We examined single sweeps of auditory late response (ALR) with the complex continuous wavelet transform. The phase in the frequency band that is associated with auditory attention (6–10 Hz, termed as theta–alpha border) was reset to the mean phase of the averaged EEGs. The inverse transform was applied to reconstruct the phase-modified signal. We found significant enhancement of the N100 wave in the reconstructed signal. Analysis of the phase noise shows the effects of phase jittering on the generation of the N100 wave implying that a preferred phase is necessary to generate the event-related potential (ERP). Power spectrum analysis shows a remarkable increase of evoked power but little change of total power after stabilizing the phase of EEGs. Furthermore, by resetting the phase only at the theta border of no attention data to the mean phase of attention data yields a result that resembles attention data. These results show strong connections between EEGs and ERP, in particular, we suggest that the presentation of an auditory stimulus triggers the phase reset process at the theta–alpha border which leads to the emergence of the N100 wave. It is concluded that our study reinforces other studies on the importance of the EEG in ERP genesis

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

    Directory of Open Access Journals (Sweden)

    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.

  18. An exploration of spatial auditory BCI paradigms with different sounds: music notes versus beeps.

    Science.gov (United States)

    Huang, Minqiang; Daly, Ian; Jin, Jing; Zhang, Yu; Wang, Xingyu; Cichocki, Andrzej

    2016-06-01

    Visual brain-computer interfaces (BCIs) are not suitable for people who cannot reliably maintain their eye gaze. Considering that this group usually maintains audition, an auditory based BCI may be a good choice for them. In this paper, we explore two auditory patterns: (1) a pattern utilizing symmetrical spatial cues with multiple frequency beeps [called the high low medium (HLM) pattern], and (2) a pattern utilizing non-symmetrical spatial cues with six tones derived from the diatonic scale [called the diatonic scale (DS) pattern]. These two patterns are compared to each other in terms of accuracy to determine which auditory pattern is better. The HLM pattern uses three different frequency beeps and has a symmetrical spatial distribution. The DS pattern uses six spoken stimuli, which are six notes solmizated as "do", "re", "mi", "fa", "sol" and "la", and derived from the diatonic scale. These six sounds are distributed to six, spatially distributed, speakers. Thus, we compare a BCI paradigm using beeps with another BCI paradigm using tones on the diatonic scale, when the stimuli are spatially distributed. Although no significant differences are found between the ERPs, the HLM pattern performs better than the DS pattern: the online accuracy achieved with the HLM pattern is significantly higher than that achieved with the DS pattern (p = 0.0028). PMID:27275376

  19. A computational model of the auditory periphery for speech and hearing research. I. Ascending path.

    Science.gov (United States)

    Giguère, C; Woodland, P C

    1994-01-01

    A dual analog/digital model of the ascending path through the entire auditory periphery is described. The analog representation consists of the concatenation of electrical circuit submodels for (a) the diffraction of the external ear system; (b) the propagation through the concha and auditory canal; (c) the transmission through the middle ear; (d) the basilar membrane motion and cochlear hydrodynamics; (e) the fast motile mechanism of the outer hair cells; and (f) the neural transduction process of the inner hair cells. Time-domain numerical solutions are obtained by applying the technique of wave digital filtering onto the resulting analog circuit. The present version of the model reproduces the sound pressure gain at the eardrum for lateral sound incidence, the vibration characteristics of the stapes, and the low-frequency attenuation provided by the stapedial muscle. Source elements in the cochlear module provide level-dependent basilar membrane tuning curves leading to dynamic compression of input signals near the characteristic frequency/place. The output is the tonotopic distribution of firing activity in the auditory nerve. A companion article addresses the modeling of the descending paths [C. Giguère and P. C. Woodland, J. Acoust, Soc. Am. 94, 343-349 (1993)]. PMID:8120244

  20. Music for the birds: effects of auditory enrichment on captive bird species.

    Science.gov (United States)

    Robbins, Lindsey; Margulis, Susan W

    2016-01-01

    With the increase of mixed species exhibits in zoos, targeting enrichment for individual species may be problematic. Often, mammals may be the primary targets of enrichment, yet other species that share their environment (such as birds) will unavoidably be exposed to the enrichment as well. The purpose of this study was to determine if (1) auditory stimuli designed for enrichment of primates influenced the behavior of captive birds in the zoo setting, and (2) if the specific type of auditory enrichment impacted bird behavior. Three different African bird species were observed at the Buffalo Zoo during exposure to natural sounds, classical music and rock music. The results revealed that the average frequency of flying in all three bird species increased with naturalistic sounds and decreased with rock music (F = 7.63, df = 3,6, P = 0.018); vocalizations for two of the three species (Superb Starlings and Mousebirds) increased (F = 18.61, df = 2,6, P = 0.0027) in response to all auditory stimuli, however one species (Lady Ross's Turacos) increased frequency of duetting only in response to rock music (X(2) = 18.5, df = 2, P influence behavior in non-target species as well, in this case leading to increased activity by birds. PMID:26749511

  1. Monitoramento auditivo na ototoxidade Auditory monitoring in ototoxicity

    Directory of Open Access Journals (Sweden)

    Lilian Cassia Bornia Jacob

    2006-12-01

    pertaining literature analysis identified two procedures often used worldwide for the early detection of auditory lesions induced by ototoxic pharmaceutical drugs: high-frequency audiometry and evoked otoacoustic emissions. Both allow early identification of hearing disorders before changes are seen in conventional pure-tone audiometry and, consequently, before speech understanding is compromised. CONCLUSION: we suggest a hearing monitoring protocol, considering the patient’s capability to respond to behavioral tests and monitoring timing (first test/follow up. For cancer patients, hearing monitoring should be performed in the patient’s treatment venue.

  2. 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.

  3. Hyperactive auditory processing in Williams syndrome: Evidence from auditory evoked potentials.

    Science.gov (United States)

    Zarchi, Omer; Avni, Chen; Attias, Josef; Frisch, Amos; Carmel, Miri; Michaelovsky, Elena; Green, Tamar; Weizman, Abraham; Gothelf, Doron

    2015-06-01

    The neurophysiologic aberrations underlying the auditory hypersensitivity in Williams syndrome (WS) are not well defined. The P1-N1-P2 obligatory complex and mismatch negativity (MMN) response were investigated in 18 participants with WS, and the results were compared with those of 18 age- and gender-matched typically developing (TD) controls. Results revealed significantly higher amplitudes of both the P1-N1-P2 obligatory complex and the MMN response in the WS participants than in the TD controls. The P1-N1-P2 complex showed an age-dependent reduction in the TD but not in the WS participants. Moreover, high P1-N1-P2 complex was associated with low verbal comprehension scores in WS. This investigation demonstrates that central auditory processing is hyperactive in WS. The increase in auditory brain responses of both the obligatory complex and MMN response suggests aberrant processes of auditory encoding and discrimination in WS. Results also imply that auditory processing may be subjected to a delayed or diverse maturation and may affect the development of high cognitive functioning in WS. PMID:25603839

  4. Personal Computer Based Clinical Programming Software for Auditory Prostheses

    Directory of Open Access Journals (Sweden)

    K. Rajakumar

    2009-01-01

    Full Text Available Auditory Prostheses (AP are widely used electronic devices for patients suffering with severe to profound senosorineural deafness by electrically stimulating the auditory nerve using an electrode array surgically placed in the inner ear. AP mainly contains external Body Worn Speech Processor (BWSP and internal Implantable Receiver Stimulator (IRS. BWSP receives an external sound or speech and generates encoded speech data bits for transmission to IRS via radio frequency transcutaneous link for excitation of electrode array. After surgical placement electrode array in the inner ear, BWSP should be fine tuned to achieve the 80-100% speech reception abilities of patient by an audiologist. Problem statement: Basic objective of this research was to develop a simple personal computer based user friendly hardware and software interface to fine tune the BWSP to achieve the best possible speech reception abilities of each individual patient. Approach: Tuning process involved several tasks such as identifying the active electrode contacts, determination of detection and pain thresholds of each active electrode and loads these values into BWSP by reprogramming the BWSP. This study contracted with development of easy and simple user friendly hardware and software interface for audiologist to perform post operation tuning procedures. A microcontroller based impedance telemetry with bidirectional RF transceiver was developed as a hardware interface between PC and IRS. The clinical programming software was developed using VB.NET 2008 to perform the post-operative tuning procedures such as (i impedance measurement, (ii fitting to determine the threshold and comfort levels for each active electrodes and (iii reprogramming the speech processor. Results: Simple hardware and software interfaces for audiologist were constructed and tested with laboratory model BWSP and IRS using simulated resistance electrode array. All the functional aspects were tested and results

  5. Spectro-temporal analysis of complex sounds in the human auditory system

    DEFF Research Database (Denmark)

    Piechowiak, Tobias

    2009-01-01

    audibility when embedded in similar background interferers, a phenomenon referred to as comodulation masking release (CMR). Knowledge of the auditory processing of amplitude modulations provides therefore crucial information for a better understanding of how the auditory system analyses acoustic scenes. The......Most sounds encountered in our everyday life carry information in terms of temporal variations of their envelopes. These envelope variations, or amplitude modulations, shape the basic building blocks for speech, music, and other complex sounds. Often a mixture of such sounds occurs in natural...... acoustic scenes, with each of the sounds having its own characteristic pattern of amplitude modulations. Complex sounds, such as speech, share the same amplitude modulations across a wide range of frequencies. This "comodulation" is an important characteristic of these sounds since it can enhance their...

  6. Profiles of hippocampal neuron activity during auditory discrimination cognition in guinea pigs

    Institute of Scientific and Technical Information of China (English)

    GAO Jie; LUO Jun; XIONG Ying; YANG Ce; WANG Yong-tang; SUI Jian-feng

    2007-01-01

    Objective: To clarify the firing characteristics of the hippocampal pyramidal cells and interneurons in the auditory discrimination cognition. Methods: Thirteen guinea pigs were studied by the paired (active cognition group, n=10) or unpaired (passive cognition group, n=3) training with 1 kHz (CS+)and 500 Hz tones (CS-) and the air puff (US) applied 250 ms after the CS+ onset. Results: In active group, 32 pyramidal cells showed exciting response to the CS+ tone, 16 cells inhibited response and 4 cells revealed no response to the high frequency tone and18 interneurons almost unchanged. In passive group, the pyramidal cells responded to the tone casually and 10 out of the 13 interneurons remained invariably. Conclusion: The result suggests that the pyramidal cells play a major role in coding auditory information by the networks, and the interneuons may modulate it via forward and feedback.

  7. Implicit temporal expectation attenuates auditory attentional blink.

    Directory of Open Access Journals (Sweden)

    Dawei Shen

    Full Text Available Attentional blink (AB describes a phenomenon whereby correct identification of a first target impairs the processing of a second target (i.e., probe nearby in time. Evidence suggests that explicit attention orienting in the time domain can attenuate the AB. Here, we used scalp-recorded, event-related potentials to examine whether auditory AB is also sensitive to implicit temporal attention orienting. Expectations were set up implicitly by varying the probability (i.e., 80% or 20% that the probe would occur at the +2 or +8 position following target presentation. Participants showed a significant AB, which was reduced with the increased probe probability at the +2 position. The probe probability effect was paralleled by an increase in P3b amplitude elicited by the probe. The results suggest that implicit temporal attention orienting can facilitate short-term consolidation of the probe and attenuate auditory AB.

  8. Delayed auditory feedback in polyglot simultaneous interpreters.

    Science.gov (United States)

    Fabbro, F; Darò, V

    1995-03-01

    Twelve polyglot students of simultaneous interpretation and 12 controls (students of the faculty of Medicine) were submitted to a task of verbal fluency under amplified normal auditory feedback (NAF) and under three delayed auditory feedback (DAF) conditions with three different delay intervals (150, 200, and 250 msec). The control group showed a significant reduction in verbal fluency and a significant increase in the number of mistakes in all three DAF conditions. The interpreters' group, however, did not show any significant speech disruption neither in the subjects' mother tongue (L1) nor in their second language (L2) across all DAF conditions. Interpreters' general high verbal fluency along with their ability to pay less attention to their own verbal output make them more resistant to the interfering effects of DAF on speech. PMID:7757448

  9. Central auditory neurons have composite receptive fields.

    Science.gov (United States)

    Kozlov, Andrei S; Gentner, Timothy Q

    2016-02-01

    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. PMID:26787894

  10. 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.

  11. Auditory plasticity and speech motor learning

    OpenAIRE

    Nasir, Sazzad M.; Ostry, David J.

    2009-01-01

    Is plasticity in sensory and motor systems linked? Here, in the context of speech motor learning and perception, we test the idea sensory function is modified by motor learning and, in particular, that speech motor learning affects a speaker's auditory map. We assessed speech motor learning by using a robotic device that displaced the jaw and selectively altered somatosensory feedback during speech. We found that with practice speakers progressively corrected for the mechanical perturbation a...

  12. Inhibition in the Human Auditory Cortex

    OpenAIRE

    Koji Inui; Kei Nakagawa; Makoto Nishihara; Eishi Motomura; Ryusuke Kakigi

    2016-01-01

    Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI) in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observe...

  13. Implicit Temporal Expectation Attenuates Auditory Attentional Blink

    OpenAIRE

    Shen, Dawei; Alain, Claude

    2012-01-01

    Attentional blink (AB) describes a phenomenon whereby correct identification of a first target impairs the processing of a second target (i.e., probe) nearby in time. Evidence suggests that explicit attention orienting in the time domain can attenuate the AB. Here, we used scalp-recorded, event-related potentials to examine whether auditory AB is also sensitive to implicit temporal attention orienting. Expectations were set up implicitly by varying the probability (i.e., 80% or 20%) that the ...

  14. Adult age effects in auditory statistical learning

    OpenAIRE

    Neger, T.M.; Rietveld, A.C.M.; Janse, E.

    2015-01-01

    Statistical learning plays a key role in language processing, e.g., for speech segmentation. Older adults have been reported to show less statistical learning on the basis of visual input than younger adults. Given age-related changes in perception and cognition, we investigated whether statistical learning is also impaired in the auditory modality in older compared to younger adults and whether individual learning ability is associated with measures of perceptual (i.e., hearing sensitivity) ...

  15. Spontaneous activity in the developing auditory system.

    Science.gov (United States)

    Wang, Han Chin; Bergles, Dwight E

    2015-07-01

    Spontaneous electrical activity is a common feature of sensory systems during early development. This sensory-independent neuronal activity has been implicated in promoting their survival and maturation, as well as growth and refinement of their projections to yield circuits that can rapidly extract information about the external world. Periodic bursts of action potentials occur in auditory neurons of mammals before hearing onset. This activity is induced by inner hair cells (IHCs) within the developing cochlea, which establish functional connections with spiral ganglion neurons (SGNs) several weeks before they are capable of detecting external sounds. During this pre-hearing period, IHCs fire periodic bursts of Ca(2+) action potentials that excite SGNs, triggering brief but intense periods of activity that pass through auditory centers of the brain. Although spontaneous activity requires input from IHCs, there is ongoing debate about whether IHCs are intrinsically active and their firing periodically interrupted by external inhibitory input (IHC-inhibition model), or are intrinsically silent and their firing periodically promoted by an external excitatory stimulus (IHC-excitation model). There is accumulating evidence that inner supporting cells in Kölliker's organ spontaneously release ATP during this time, which can induce bursts of Ca(2+) spikes in IHCs that recapitulate many features of auditory neuron activity observed in vivo. Nevertheless, the role of supporting cells in this process remains to be established in vivo. A greater understanding of the molecular mechanisms responsible for generating IHC activity in the developing cochlea will help reveal how these events contribute to the maturation of nascent auditory circuits. PMID:25296716

  16. Predictive uncertainty in auditory sequence processing

    OpenAIRE

    Niels Chr.Hansen; MarcusT.Pearce

    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 e...

  17. Stroke caused auditory attention deficits in children

    Directory of Open Access Journals (Sweden)

    Karla Maria Ibraim da Freiria Elias

    2013-01-01

    Full Text Available OBJECTIVE: To verify the auditory selective attention in children with stroke. METHODS: Dichotic tests of binaural separation (non-verbal and consonant-vowel and binaural integration - digits and Staggered Spondaic Words Test (SSW - were applied in 13 children (7 boys, from 7 to 16 years, with unilateral stroke confirmed by neurological examination and neuroimaging. RESULTS: The attention performance showed significant differences in comparison to the control group in both kinds of tests. In the non-verbal test, identifications the ear opposite the lesion in the free recall stage was diminished and, in the following stages, a difficulty in directing attention was detected. In the consonant- vowel test, a modification in perceptual asymmetry and difficulty in focusing in the attended stages was found. In the digits and SSW tests, ipsilateral, contralateral and bilateral deficits were detected, depending on the characteristics of the lesions and demand of the task. CONCLUSION: Stroke caused auditory attention deficits when dealing with simultaneous sources of auditory information.

  18. Concentric scheme of monkey auditory cortex

    Science.gov (United States)

    Kosaki, Hiroko; Saunders, Richard C.; Mishkin, Mortimer

    2003-04-01

    The cytoarchitecture of the rhesus monkey's auditory cortex was examined using immunocytochemical staining with parvalbumin, calbindin-D28K, and SMI32, as well as staining for cytochrome oxidase (CO). The results suggest that Kaas and Hackett's scheme of the auditory cortices can be extended to include five concentric rings surrounding an inner core. The inner core, containing areas A1 and R, is the most densely stained with parvalbumin and CO and can be separated on the basis of laminar patterns of SMI32 staining into lateral and medial subdivisions. From the inner core to the fifth (outermost) ring, parvalbumin staining gradually decreases and calbindin staining gradually increases. The first ring corresponds to Kaas and Hackett's auditory belt, and the second, to their parabelt. SMI32 staining revealed a clear border between these two. Rings 2 through 5 extend laterally into the dorsal bank of the superior temporal sulcus. The results also suggest that the rostral tip of the outermost ring adjoins the rostroventral part of the insula (area Pro) and the temporal pole, while the caudal tip adjoins the ventral part of area 7a.

  19. 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. PMID:24715297

  20. 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.