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Sample records for cat auditory cortex

  1. Cross-correlations between three units in cat primary auditory cortex.

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    Eggermont, Jos J; Munguia, Raymundo; Shaw, Gregory

    2013-10-01

    Here we use a modification of the Joint-Peri-Stimulus-Time histogram (JPSTH) to investigate triple correlations between cat auditory cortex neurons. The modified procedure allowed the decomposition of the xy-pair correlation into a part that is due to the correlation of the x and y units with the trigger unit, and a remaining 'pair correlation'. We analyzed 16 sets of 15-minute duration stationary spontaneous recordings in primary auditory cortex (AI) with between 11 and 14 electrodes from 2 arrays of 8 electrodes each that provided spontaneous firing rates above 0.22 sp/s and for which reliable frequency-tuning curves could be obtained and the characteristic frequency (CF) was estimated. Thus we evaluated 11,282 conditional cross-correlation functions. The predictor for the conditional cross-correlation, calculated on the assumption that the trigger unit had no effect on the xy-pair correlation but using the same fraction of xy spikes, was equal to the conventional pair-wise correlation function between units xy. The conditional correlation of the xy-pair due to correlation of the x and/or y unit with the trigger unit decreased with the geometric mean distance of the xy pair to the trigger unit, but was independent of the pair cross-correlation coefficient. The conditional pair correlation coefficient was estimated at 78% of the measured pair correlation coefficient. Assuming a geometric decreasing effect of activities of units on other electrodes on the conditional correlation, we estimated the potential contribution of a large number of contributing units on the measured pair correlation at 35-50 of that correlation. This suggests that conventionally measured pair correlations in auditory cortex under ketamine anesthesia overestimate the 'true pair correlation', likely resulting from massive common input, by potentially up to a factor 2. PMID:23933479

  2. Spectrotemporal receptive fields during spindling and non-spindling epochs in cat primary auditory cortex.

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    Britvina, T; Eggermont, J J

    2008-07-17

    It was often thought that synchronized rhythmic epochs of spindle waves disconnect thalamo-cortical system from incoming sensory signals. The present study addresses this issue by simultaneous extracellular action potential and local field potential (LFP) recordings from primary auditory cortex of ketamine-anesthetized cats during spindling activity. We compared cortical spectrotemporal receptive fields (STRF) obtained during spindling and non-spindling epochs. The basic spectro-temporal parameters of "spindling" and "non-spindling" STRFs were similar. However, the peak-firing rate at the best frequency was significantly enhanced during spindling epochs. This enhancement was mainly caused by the increased probability of a stimulus to evoke spikes (effectiveness of stimuli) during spindling as compared with non-spindling epochs. Augmented LFPs associated with effective stimuli and increased single-unit pair correlations during spindling epochs suggested higher synchrony of thalamo-cortical inputs during spindling that resulted in increased effectiveness of stimuli presented during spindling activity. The neuronal firing rate, both stimulus-driven and spontaneous, was higher during spindling as compared with non-spindling epochs. Overall, our results suggests that thalamic cells during spindling respond to incoming stimuli-related inputs and, moreover, cause more powerful stimulus-related or spontaneous activation of the cortex. PMID:18515012

  3. Characterization of the blood-oxygen level-dependent (BOLD) response in cat auditory cortex using high-field fMRI.

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    Brown, Trecia A; Joanisse, Marc F; Gati, Joseph S; Hughes, Sarah M; Nixon, Pam L; Menon, Ravi S; Lomber, Stephen G

    2013-01-01

    Much of what is known about the cortical organization for audition in humans draws from studies of auditory cortex in the cat. However, these data build largely on electrophysiological recordings that are both highly invasive and provide less evidence concerning macroscopic patterns of brain activation. Optical imaging, using intrinsic signals or dyes, allows visualization of surface-based activity but is also quite invasive. Functional magnetic resonance imaging (fMRI) overcomes these limitations by providing a large-scale perspective of distributed activity across the brain in a non-invasive manner. The present study used fMRI to characterize stimulus-evoked activity in auditory cortex of an anesthetized (ketamine/isoflurane) cat, focusing specifically on the blood-oxygen-level-dependent (BOLD) signal time course. Functional images were acquired for adult cats in a 7 T MRI scanner. To determine the BOLD signal time course, we presented 1s broadband noise bursts between widely spaced scan acquisitions at randomized delays (1-12 s in 1s increments) prior to each scan. Baseline trials in which no stimulus was presented were also acquired. Our results indicate that the BOLD response peaks at about 3.5s in primary auditory cortex (AI) and at about 4.5 s in non-primary areas (AII, PAF) of cat auditory cortex. The observed peak latency is within the range reported for humans and non-human primates (3-4 s). The time course of hemodynamic activity in cat auditory cortex also occurs on a comparatively shorter scale than in cat visual cortex. The results of this study will provide a foundation for future auditory fMRI studies in the cat to incorporate these hemodynamic response properties into appropriate analyses of cat auditory cortex. PMID:23000258

  4. Encoding of temporal information by timing, rate, and place in cat auditory cortex.

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    Kazuo Imaizumi

    Full Text Available A central goal in auditory neuroscience is to understand the neural coding of species-specific communication and human speech sounds. Low-rate repetitive sounds are elemental features of communication sounds, and core auditory cortical regions have been implicated in processing these information-bearing elements. Repetitive sounds could be encoded by at least three neural response properties: 1 the event-locked spike-timing precision, 2 the mean firing rate, and 3 the interspike interval (ISI. To determine how well these response aspects capture information about the repetition rate stimulus, we measured local group responses of cortical neurons in cat anterior auditory field (AAF to click trains and calculated their mutual information based on these different codes. ISIs of the multiunit responses carried substantially higher information about low repetition rates than either spike-timing precision or firing rate. Combining firing rate and ISI codes was synergistic and captured modestly more repetition information. Spatial distribution analyses showed distinct local clustering properties for each encoding scheme for repetition information indicative of a place code. Diversity in local processing emphasis and distribution of different repetition rate codes across AAF may give rise to concurrent feed-forward processing streams that contribute differently to higher-order sound analysis.

  5. Comparison of LFP-Based and Spike-Based Spectro-Temporal Receptive Fields and Cross-Correlation in Cat Primary Auditory Cortex

    OpenAIRE

    Eggermont, Jos J.; Munguia, Raymundo; Pienkowski, Martin; Shaw, Greg

    2011-01-01

    Multi-electrode array recordings of spike and local field potential (LFP) activity were made from primary auditory cortex of 12 normal hearing, ketamine-anesthetized cats. We evaluated 259 spectro-temporal receptive fields (STRFs) and 492 frequency-tuning curves (FTCs) based on LFPs and spikes simultaneously recorded on the same electrode. We compared their characteristic frequency (CF) gradients and their cross-correlation distances. The CF gradient for spike-based FTCs was about twice that ...

  6. Encoding of Temporal Information by Timing, Rate, and Place in Cat Auditory Cortex

    OpenAIRE

    Imaizumi, Kazuo; Priebe, Nicholas J.; Sharpee, Tatyana O.; Cheung, Steven W.; Schreiner, Christoph E.

    2010-01-01

    A central goal in auditory neuroscience is to understand the neural coding of species-specific communication and human speech sounds. Low-rate repetitive sounds are elemental features of communication sounds, and core auditory cortical regions have been implicated in processing these information-bearing elements. Repetitive sounds could be encoded by at least three neural response properties: 1) the event-locked spike-timing precision, 2) the mean firing rate, and 3) the interspike interval (...

  7. Synaptic Basis for Cross-modal Plasticity: Enhanced Supragranular Dendritic Spine Density in Anterior Ectosylvian Auditory Cortex of the Early Deaf Cat.

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    Clemo, H Ruth; Lomber, Stephen G; Meredith, M Alex

    2016-04-01

    In the cat, the auditory field of the anterior ectosylvian sulcus (FAES) is sensitive to auditory cues and its deactivation leads to orienting deficits toward acoustic, but not visual, stimuli. However, in early deaf cats, FAES activity shifts to the visual modality and its deactivation blocks orienting toward visual stimuli. Thus, as in other auditory cortices, hearing loss leads to cross-modal plasticity in the FAES. However, the synaptic basis for cross-modal plasticity is unknown. Therefore, the present study examined the effect of early deafness on the density, distribution, and size of dendritic spines in the FAES. Young cats were ototoxically deafened and raised until adulthood when they (and hearing controls) were euthanized, the cortex stained using Golgi-Cox, and FAES neurons examined using light microscopy. FAES dendritic spine density averaged 0.85 spines/μm in hearing animals, but was significantly higher (0.95 spines/μm) in the early deaf. Size distributions and increased spine density were evident specifically on apical dendrites of supragranular neurons. In separate tracer experiments, cross-modal cortical projections were shown to terminate predominantly within the supragranular layers of the FAES. This distributional correspondence between projection terminals and dendritic spine changes indicates that cross-modal plasticity is synaptically based within the supragranular layers of the early deaf FAES. PMID:25274986

  8. 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...

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

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

    2016-03-01

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

  10. Comparison of LFP-based and spike-based spectro-temporal receptive fields and cross-correlation in cat primary auditory cortex.

    Directory of Open Access Journals (Sweden)

    Jos J Eggermont

    Full Text Available Multi-electrode array recordings of spike and local field potential (LFP activity were made from primary auditory cortex of 12 normal hearing, ketamine-anesthetized cats. We evaluated 259 spectro-temporal receptive fields (STRFs and 492 frequency-tuning curves (FTCs based on LFPs and spikes simultaneously recorded on the same electrode. We compared their characteristic frequency (CF gradients and their cross-correlation distances. The CF gradient for spike-based FTCs was about twice that for 2-40 Hz-filtered LFP-based FTCs, indicating greatly reduced frequency selectivity for LFPs. We also present comparisons for LFPs band-pass filtered between 4-8 Hz, 8-16 Hz and 16-40 Hz, with spike-based STRFs, on the basis of their marginal frequency distributions. We find on average a significantly larger correlation between the spike based marginal frequency distributions and those based on the 16-40 Hz filtered LFP, compared to those based on the 4-8 Hz, 8-16 Hz and 2-40 Hz filtered LFP. This suggests greater frequency specificity for the 16-40 Hz LFPs compared to those of lower frequency content. For spontaneous LFP and spike activity we evaluated 1373 pair correlations for pairs with >200 spikes in 900 s per electrode. Peak correlation-coefficient space constants were similar for the 2-40 Hz filtered LFP (5.5 mm and the 16-40 Hz LFP (7.4 mm, whereas for spike-pair correlations it was about half that, at 3.2 mm. Comparing spike-pairs with 2-40 Hz (and 16-40 Hz LFP-pair correlations showed that about 16% (9% of the variance in the spike-pair correlations could be explained from LFP-pair correlations recorded on the same electrodes within the same electrode array. This larger correlation distance combined with the reduced CF gradient and much broader frequency selectivity suggests that LFPs are not a substitute for spike activity in primary auditory cortex.

  11. Comparison of LFP-based and spike-based spectro-temporal receptive fields and cross-correlation in cat primary auditory cortex.

    Science.gov (United States)

    Eggermont, Jos J; Munguia, Raymundo; Pienkowski, Martin; Shaw, Greg

    2011-01-01

    Multi-electrode array recordings of spike and local field potential (LFP) activity were made from primary auditory cortex of 12 normal hearing, ketamine-anesthetized cats. We evaluated 259 spectro-temporal receptive fields (STRFs) and 492 frequency-tuning curves (FTCs) based on LFPs and spikes simultaneously recorded on the same electrode. We compared their characteristic frequency (CF) gradients and their cross-correlation distances. The CF gradient for spike-based FTCs was about twice that for 2-40 Hz-filtered LFP-based FTCs, indicating greatly reduced frequency selectivity for LFPs. We also present comparisons for LFPs band-pass filtered between 4-8 Hz, 8-16 Hz and 16-40 Hz, with spike-based STRFs, on the basis of their marginal frequency distributions. We find on average a significantly larger correlation between the spike based marginal frequency distributions and those based on the 16-40 Hz filtered LFP, compared to those based on the 4-8 Hz, 8-16 Hz and 2-40 Hz filtered LFP. This suggests greater frequency specificity for the 16-40 Hz LFPs compared to those of lower frequency content. For spontaneous LFP and spike activity we evaluated 1373 pair correlations for pairs with >200 spikes in 900 s per electrode. Peak correlation-coefficient space constants were similar for the 2-40 Hz filtered LFP (5.5 mm) and the 16-40 Hz LFP (7.4 mm), whereas for spike-pair correlations it was about half that, at 3.2 mm. Comparing spike-pairs with 2-40 Hz (and 16-40 Hz) LFP-pair correlations showed that about 16% (9%) of the variance in the spike-pair correlations could be explained from LFP-pair correlations recorded on the same electrodes within the same electrode array. This larger correlation distance combined with the reduced CF gradient and much broader frequency selectivity suggests that LFPs are not a substitute for spike activity in primary auditory cortex. PMID:21625385

  12. Auditory Connections and Functions of Prefrontal Cortex

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    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.

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

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    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

  14. Encoding frequency contrast in primate auditory cortex

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    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...

  15. Inhibition in the Human Auditory Cortex

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    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...

  16. Lateralization of auditory-cortex functions.

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    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

  17. Network and external perturbation induce burst synchronisation in cat cerebral cortex

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    Lameu, Ewandson L.; Borges, Fernando S.; Borges, Rafael R.; Batista, Antonio M.; Baptista, Murilo S.; Viana, Ricardo L.

    2016-05-01

    The brain of mammals are divided into different cortical areas that are anatomically connected forming larger networks which perform cognitive tasks. The cat cerebral cortex is composed of 65 areas organised into the visual, auditory, somatosensory-motor and frontolimbic cognitive regions. We have built a network of networks, in which networks are connected among themselves according to the connections observed in the cat cortical areas aiming to study how inputs drive the synchronous behaviour in this cat brain-like network. We show that without external perturbations it is possible to observe high level of bursting synchronisation between neurons within almost all areas, except for the auditory area. Bursting synchronisation appears between neurons in the auditory region when an external perturbation is applied in another cognitive area. This is a clear evidence that burst synchronisation and collective behaviour in the brain might be a process mediated by other brain areas under stimulation.

  18. Concentric scheme of monkey auditory cortex

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    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. 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...

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

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    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.

  1. Characterization of auditory synaptic inputs to gerbil perirhinal cortex

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    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. Auditory Cortex Basal Activity Modulates Cochlear Responses in Chinchillas

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    León, Alex; Elgueda, Diego; Silva, María A.; Hamamé, Carlos M.; Delano, Paul H.

    2012-01-01

    Background The auditory efferent system has unique neuroanatomical pathways that connect the cerebral cortex with sensory receptor cells. Pyramidal neurons located in layers V and VI of the primary auditory cortex constitute descending projections to the thalamus, inferior colliculus, and even directly to the superior olivary complex and to the cochlear nucleus. Efferent pathways are connected to the cochlear receptor by the olivocochlear system, which innervates outer hair cells and auditory...

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

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    Elsa van der Loo

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

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

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    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.

  5. The cat's meow: A high-field fMRI assessment of cortical activity in response to vocalizations and complex auditory stimuli.

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    Hall, Amee J; Butler, Blake E; Lomber, Stephen G

    2016-02-15

    Sensory systems are typically constructed in a hierarchical fashion such that lower level subcortical and cortical areas process basic stimulus features, while higher level areas reassemble these features into object-level representations. A number of anatomical pathway tracing studies have suggested that the auditory cortical hierarchy of the cat extends from a core region, consisting of the primary auditory cortex (A1) and the anterior auditory field (AAF), to higher level auditory fields that are located ventrally. Unfortunately, limitations on electrophysiological examination of these higher level fields have resulted in an incomplete understanding of the functional organization of the auditory cortex. Thus, the current study uses functional MRI in conjunction with a variety of simple and complex auditory stimuli to provide the first comprehensive examination of function across the entire cortical hierarchy. Auditory cortex function is shown to be largely lateralized to the left hemisphere, and is concentrated bilaterally in fields surrounding the posterior ectosylvian sulcus. The use of narrowband noise stimuli enables the visualization of tonotopic gradients in the posterior auditory field (PAF) and ventral posterior auditory field (VPAF) that have previously been unverifiable using fMRI and pure tones. Furthermore, auditory fields that are inaccessible to more invasive techniques, such as the insular (IN) and temporal (T) cortices, are shown to be selectively responsive to vocalizations. Collectively, these data provide a much needed functional correlate for anatomical examinations of the hierarchy of cortical structures within the cat auditory cortex. PMID:26658927

  6. Functional sex differences in human primary auditory cortex

    NARCIS (Netherlands)

    Ruytjens, Liesbet; Georgiadis, Janniko R.; Holstege, Gert; Wit, Hero P.; Albers, Frans W. J.; Willemsen, Antoon T. M.

    2007-01-01

    Background We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a bas

  7. Inhibition in the Human Auditory Cortex.

    Directory of Open Access Journals (Sweden)

    Koji Inui

    Full Text Available 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 observed by inserting a weak (5 dB increase for 1 ms prepulse. The time course of the inhibition evaluated by prepulses presented at 10-800 ms before the test stimulus showed at least two temporally distinct inhibitions peaking at approximately 20-60 and 600 ms that presumably reflected IPSPs by fast spiking, parvalbumin-positive cells and somatostatin-positive, Martinotti cells, respectively. In another experiment, we confirmed that the degree of the inhibition depended on the strength of the prepulse, but not on the amplitude of the prepulse-evoked cortical response, indicating that the prepulse-evoked excitatory response and prepulse-evoked inhibition reflected activation in two different pathways. Although many diseases such as schizophrenia may involve deficits in the inhibitory system, we do not have appropriate methods to evaluate them; therefore, the easy and non-invasive method described herein may be clinically useful.

  8. Functional sex differences in human primary auditory cortex

    International Nuclear Information System (INIS)

    We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a baseline (no auditory stimulation). We found a sex difference in activation of the left and right PAC when comparing music to noise. The PAC was more activated by music than by noise in both men and women. But this difference between the two stimuli was significantly higher in men than in women. To investigate whether this difference could be attributed to either music or noise, we compared both stimuli with the baseline and revealed that noise gave a significantly higher activation in the female PAC than in the male PAC. Moreover, the male group showed a deactivation in the right prefrontal cortex when comparing noise to the baseline, which was not present in the female group. Interestingly, the auditory and prefrontal regions are anatomically and functionally linked and the prefrontal cortex is known to be engaged in auditory tasks that involve sustained or selective auditory attention. Thus we hypothesize that differences in attention result in a different deactivation of the right prefrontal cortex, which in turn modulates the activation of the PAC and thus explains the sex differences found in the activation of the PAC. Our results suggest that sex is an important factor in auditory brain studies. (orig.)

  9. Functional sex differences in human primary auditory cortex

    Energy Technology Data Exchange (ETDEWEB)

    Ruytjens, Liesbet [University Medical Center Groningen, Department of Otorhinolaryngology, Groningen (Netherlands); University Medical Center Utrecht, Department Otorhinolaryngology, P.O. Box 85500, Utrecht (Netherlands); Georgiadis, Janniko R. [University of Groningen, University Medical Center Groningen, Department of Anatomy and Embryology, Groningen (Netherlands); Holstege, Gert [University of Groningen, University Medical Center Groningen, Center for Uroneurology, Groningen (Netherlands); Wit, Hero P. [University Medical Center Groningen, Department of Otorhinolaryngology, Groningen (Netherlands); Albers, Frans W.J. [University Medical Center Utrecht, Department Otorhinolaryngology, P.O. Box 85500, Utrecht (Netherlands); Willemsen, Antoon T.M. [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands)

    2007-12-15

    We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a baseline (no auditory stimulation). We found a sex difference in activation of the left and right PAC when comparing music to noise. The PAC was more activated by music than by noise in both men and women. But this difference between the two stimuli was significantly higher in men than in women. To investigate whether this difference could be attributed to either music or noise, we compared both stimuli with the baseline and revealed that noise gave a significantly higher activation in the female PAC than in the male PAC. Moreover, the male group showed a deactivation in the right prefrontal cortex when comparing noise to the baseline, which was not present in the female group. Interestingly, the auditory and prefrontal regions are anatomically and functionally linked and the prefrontal cortex is known to be engaged in auditory tasks that involve sustained or selective auditory attention. Thus we hypothesize that differences in attention result in a different deactivation of the right prefrontal cortex, which in turn modulates the activation of the PAC and thus explains the sex differences found in the activation of the PAC. Our results suggest that sex is an important factor in auditory brain studies. (orig.)

  10. Neurogenesis in the brain auditory pathway of a marsupial, the northern native cat (Dasyurus hallucatus)

    International Nuclear Information System (INIS)

    Neurogenesis in the auditory pathway of the marsupial Dasyurus hallucatus was studied. Intraperitoneal injections of tritiated thymidine (20-40 microCi) were made into pouch-young varying from 1 to 56 days pouch-life. Animals were killed as adults and brain sections were prepared for autoradiography and counterstained with a Nissl stain. Neurons in the ventral cochlear nucleus were generated prior to 3 days pouch-life, in the superior olive at 5-7 days, and in the dorsal cochlear nucleus over a prolonged period. Inferior collicular neurogenesis lagged behind that in the medial geniculate, the latter taking place between days 3 and 9 and the former between days 7 and 22. Neurogenesis began in the auditory cortex on day 9 and was completed by about day 42. Thus neurogenesis was complete in the medullary auditory nuclei before that in the midbrain commenced, and in the medial geniculate before that in the auditory cortex commenced. The time course of neurogenesis in the auditory pathway of the native cat was very similar to that in another marsupial, the brushtail possum. For both, neurogenesis occurred earlier than in eutherian mammals of a similar size but was more protracted

  11. Neurogenesis in the brain auditory pathway of a marsupial, the northern native cat (Dasyurus hallucatus)

    Energy Technology Data Exchange (ETDEWEB)

    Aitkin, L.; Nelson, J.; Farrington, M.; Swann, S. (Department of Physiology, Monash University, Melbourne (Australia))

    1991-07-08

    Neurogenesis in the auditory pathway of the marsupial Dasyurus hallucatus was studied. Intraperitoneal injections of tritiated thymidine (20-40 microCi) were made into pouch-young varying from 1 to 56 days pouch-life. Animals were killed as adults and brain sections were prepared for autoradiography and counterstained with a Nissl stain. Neurons in the ventral cochlear nucleus were generated prior to 3 days pouch-life, in the superior olive at 5-7 days, and in the dorsal cochlear nucleus over a prolonged period. Inferior collicular neurogenesis lagged behind that in the medial geniculate, the latter taking place between days 3 and 9 and the former between days 7 and 22. Neurogenesis began in the auditory cortex on day 9 and was completed by about day 42. Thus neurogenesis was complete in the medullary auditory nuclei before that in the midbrain commenced, and in the medial geniculate before that in the auditory cortex commenced. The time course of neurogenesis in the auditory pathway of the native cat was very similar to that in another marsupial, the brushtail possum. For both, neurogenesis occurred earlier than in eutherian mammals of a similar size but was more protracted.

  12. Altered intrinsic connectivity of the auditory cortex in congenital amusia.

    Science.gov (United States)

    Leveque, Yohana; Fauvel, Baptiste; Groussard, Mathilde; Caclin, Anne; Albouy, Philippe; Platel, Hervé; Tillmann, Barbara

    2016-07-01

    Congenital amusia, a neurodevelopmental disorder of music perception and production, has been associated with abnormal anatomical and functional connectivity in a right frontotemporal pathway. To investigate whether spontaneous connectivity in brain networks involving the auditory cortex is altered in the amusic brain, we ran a seed-based connectivity analysis, contrasting at-rest functional MRI data of amusic and matched control participants. Our results reveal reduced frontotemporal connectivity in amusia during resting state, as well as an overconnectivity between the auditory cortex and the default mode network (DMN). The findings suggest that the auditory cortex is intrinsically more engaged toward internal processes and less available to external stimuli in amusics compared with controls. Beyond amusia, our findings provide new evidence for the link between cognitive deficits in pathology and abnormalities in the connectivity between sensory areas and the DMN at rest. PMID:27009161

  13. 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

  14. Intrahemispheric cortico-cortical connections of the human auditory cortex.

    Science.gov (United States)

    Cammoun, Leila; Thiran, Jean Philippe; Griffa, Alessandra; Meuli, Reto; Hagmann, Patric; Clarke, Stephanie

    2015-11-01

    The human auditory cortex comprises the supratemporal plane and large parts of the temporal and parietal convexities. We have investigated the relevant intrahemispheric cortico-cortical connections using in vivo DSI tractography combined with landmark-based registration, automatic cortical parcellation and whole-brain structural connection matrices in 20 right-handed male subjects. On the supratemporal plane, the pattern of connectivity was related to the architectonically defined early-stage auditory areas. It revealed a three-tier architecture characterized by a cascade of connections from the primary auditory cortex to six adjacent non-primary areas and from there to the superior temporal gyrus. Graph theory-driven analysis confirmed the cascade-like connectivity pattern and demonstrated a strong degree of segregation and hierarchy within early-stage auditory areas. Putative higher-order areas on the temporal and parietal convexities had more widely spread local connectivity and long-range connections with the prefrontal cortex; analysis of optimal community structure revealed five distinct modules in each hemisphere. The pattern of temporo-parieto-frontal connectivity was partially asymmetrical. In conclusion, the human early-stage auditory cortical connectivity, as revealed by in vivo DSI tractography, has strong similarities with that of non-human primates. The modular architecture and hemispheric asymmetry in higher-order regions is compatible with segregated processing streams and lateralization of cognitive functions. PMID:25173473

  15. 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.

  16. Music perception and cognition following bilateral lesions of auditory cortex.

    Science.gov (United States)

    Tramo, M J; Bharucha, J J; Musiek, F E

    1990-01-01

    We present experimental and anatomical data from a case study of impaired auditory perception following bilateral hemispheric strokes. To consider the cortical representation of sensory, perceptual, and cognitive functions mediating tonal information processing in music, pure tone sensation thresholds, spectral intonation judgments, and the associative priming of spectral intonation judgments by harmonic context were examined, and lesion localization was analyzed quantitatively using straight-line two-dimensional maps of the cortical surface reconstructed from magnetic resonance images. Despite normal pure tone sensation thresholds at 250-8000 Hz, the perception of tonal spectra was severely impaired, such that harmonic structures (major triads) were almost uniformly judged to sound dissonant; yet, the associative priming of spectral intonation judgments by harmonic context was preserved, indicating that cognitive representations of tonal hierarchies in music remained intact and accessible. Brainprints demonstrated complete bilateral lesions of the transverse gyri of Heschl and partial lesions of the right and left superior temporal gyri involving 98 and 20% of their surface areas, respectively. In the right hemisphere, there was partial sparing of the planum temporale, temporoparietal junction, and inferior parietal cortex. In the left hemisphere, all of the superior temporal region anterior to the transverse gyrus and parts of the planum temporale, temporoparietal junction, inferior parietal cortex, and insula were spared. These observations suggest that (1) sensory, perceptual, and cognitive functions mediating tonal information processing in music are neurologically dissociable; (2) complete bilateral lesions of primary auditory cortex combined with partial bilateral lesions of auditory association cortex chronically impair tonal consonance perception; (3) cognitive functions that hierarchically structure pitch information and generate harmonic expectancies

  17. Fine functional organization of auditory cortex revealed by Fourier optical imaging

    OpenAIRE

    Kalatsky, Valery A.; Polley, Daniel B.; Merzenich, Michael M.; Schreiner, Christoph E.; Stryker, Michael P.

    2005-01-01

    We provide an overall view of the functional tonotopic organization of the auditory cortex in the rat. We apply a recently developed technique for acquiring intrinsic signal optical maps, Fourier imaging, in the rat auditory cortex. These highly detailed maps, derived in a several-minute-long recording procedure, delineate multiple auditory cortical areas and demonstrate their shapes, sizes, and tonotopic order. Beyond the primary auditory cortex, there are at least three distinct areas with ...

  18. 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

  19. 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...

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

    Directory of Open Access Journals (Sweden)

    Tomás Hromádka

    2008-01-01

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

  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. Cochlear injury and adaptive plasticity of the auditory cortex

    Directory of Open Access Journals (Sweden)

    ANNA R. eFETONI

    2015-02-01

    Full Text Available Growing evidence suggests that cochlear stressors as noise exposure and aging can induce homeostatic/maladaptive changes in the central auditory system from the brainstem to the cortex. Studies centered on such changes have revealed several mechanisms that operate in the context of sensory disruption after insult (noise trauma, drug- or age-related injury. The oxidative stress is central to current theories of induced sensory neural hearing loss and aging, and interventions to attenuate the hearing loss are based on antioxidant agent. The present review addresses the recent literature on the alterations in hair cells and spiral ganglion neurons due to noise-induced oxidative stress in the cochlea, as well on the impact of cochlear damage on the auditory cortex neurons. The emerging image emphasizes that noise-induced deafferentation and upward spread of cochlear damage is associated with the altered dendritic architecture of auditory pyramidal neurons. The cortical modifications may be reversed by treatment with antioxidants counteracting the cochlear redox imbalance. These findings open new therapeutic approaches to treat the functional consequences of the cortical reorganization following cochlear damage.

  3. Cochlear injury and adaptive plasticity of the auditory cortex.

    Science.gov (United States)

    Fetoni, Anna Rita; Troiani, Diana; Petrosini, Laura; Paludetti, Gaetano

    2015-01-01

    Growing evidence suggests that cochlear stressors as noise exposure and aging can induce homeostatic/maladaptive changes in the central auditory system from the brainstem to the cortex. Studies centered on such changes have revealed several mechanisms that operate in the context of sensory disruption after insult (noise trauma, drug-, or age-related injury). The oxidative stress is central to current theories of induced sensory-neural hearing loss and aging, and interventions to attenuate the hearing loss are based on antioxidant agent. The present review addresses the recent literature on the alterations in hair cells and spiral ganglion neurons due to noise-induced oxidative stress in the cochlea, as well on the impact of cochlear damage on the auditory cortex neurons. The emerging image emphasizes that noise-induced deafferentation and upward spread of cochlear damage is associated with the altered dendritic architecture of auditory pyramidal neurons. The cortical modifications may be reversed by treatment with antioxidants counteracting the cochlear redox imbalance. These findings open new therapeutic approaches to treat the functional consequences of the cortical reorganization following cochlear damage. PMID:25698966

  4. 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.

  5. Multi-sensory integration in brainstem and auditory cortex.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience

  6. The Representation of Prediction Error in Auditory Cortex

    Science.gov (United States)

    Rubin, Jonathan; Ulanovsky, Nachum; Tishby, Naftali

    2016-01-01

    To survive, organisms must extract information from the past that is relevant for their future. How this process is expressed at the neural level remains unclear. We address this problem by developing a novel approach from first principles. We show here how to generate low-complexity representations of the past that produce optimal predictions of future events. We then illustrate this framework by studying the coding of ‘oddball’ sequences in auditory cortex. We find that for many neurons in primary auditory cortex, trial-by-trial fluctuations of neuronal responses correlate with the theoretical prediction error calculated from the short-term past of the stimulation sequence, under constraints on the complexity of the representation of this past sequence. In some neurons, the effect of prediction error accounted for more than 50% of response variability. Reliable predictions often depended on a representation of the sequence of the last ten or more stimuli, although the representation kept only few details of that sequence. PMID:27490251

  7. Acoustic trauma-induced auditory cortex enhancement and tinnitus

    Institute of Scientific and Technical Information of China (English)

    Erin Laundrie; Wei Sun

    2014-01-01

    There is growing evidence suggests that noise-induced cochlear damage may lead to hyperexcitability in the central auditory system (CAS) which may give rise to tinnitus. However, the correlation between the onset of the neurophysiological changes in the CAS and the onset of tinnitus has not been well studied. To investigate this relationship, chronic electrodes were implanted into the auditory cortex (AC) and sound evoked activities were measured from awake rats before and after noise exposure. The auditory brainstem response (ABR) was used to assess the degree of noise-induced hearing loss. Tinnitus was evaluated by measuring gap-induced prepulse inhibition (gap-PPI). Rats were exposed monaurally to a high-intensity narrowband noise centered at 12 kHz at a level of 120 dB SPL for 1 h. After the noise exposure, all the rats developed either permanent (>2 weeks) or temporary (<3 days) hearing loss in the exposed ear(s). The AC amplitudes increased significantly 4 h after the noise exposure. Most of the exposed rats also showed decreased gap-PPI. The post-exposure AC enhancement showed a positive correlation with the amount of hearing loss. The onset of tinnitus-like behavior was happened after the onset of AC enhancement.

  8. Formation of associations in auditory cortex by slow changes of tonic firing.

    Science.gov (United States)

    Brosch, Michael; Selezneva, Elena; Scheich, Henning

    2011-01-01

    We review event-related slow firing changes in the auditory cortex and related brain structures. Two types of changes can be distinguished, namely increases and decreases of firing, lasting in the order of seconds. Triggering events can be auditory stimuli, reinforcers, and behavioral responses. Slow firing changes terminate with reinforcers and possibly with auditory stimuli and behavioral responses. A necessary condition for the emergence of slow firing changes seems to be that subjects have learnt that consecutive sensory or behavioral events are contingent on reinforcement. They disappear when the contingencies are no longer present. Slow firing changes in auditory cortex bear similarities with slow changes of neuronal activity that have been observed in subcortical parts of the auditory system and in other non-sensory brain structures. We propose that slow firing changes in auditory cortex provide a neuronal mechanism for anticipating, memorizing, and associating events that are related to hearing and of behavioral relevance. This may complement the representation of the timing and types of auditory and auditory-related events which may be provided by phasic responses in auditory cortex. The presence of slow firing changes indicates that many more auditory-related aspects of a behavioral procedure are reflected in the neuronal activity of auditory cortex than previously assumed. PMID:20488230

  9. 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...

  10. Diffusion tensor imaging and MR morphometry of the central auditory pathway and auditory cortex in aging

    Czech Academy of Sciences Publication Activity Database

    Profant, Oliver; Škoch, A.; Balogová, Zuzana; Tintěra, J.; Hlinka, Jaroslav; Syka, Josef

    2014-01-01

    Roč. 260, FEB 28 (2014), s. 87-97. ISSN 0306-4522 R&D Projects: GA ČR GAP304/10/1872; GA ČR(CZ) GBP304/12/G069; GA ČR GA13-23940S Grant ostatní: GA MŠk(CZ) Prvouk-P27/LF1/1 Institutional support: RVO:68378041 ; RVO:67985807 Keywords : presbycusis * aging * auditory cortex Subject RIV: FH - Neurology Impact factor: 3.357, year: 2014

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

    Directory of Open Access Journals (Sweden)

    Ling-Chia Chen

    2016-01-01

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

  12. Functional studies of the human auditory cortex, auditory memory and musical hallucinations

    International Nuclear Information System (INIS)

    Objectives. 1. To determine which areas of the cerebral cortex are activated stimulating the left ear with pure tones, and what type of stimulation occurs (eg. excitatory or inhibitory) in these different areas. 2. To use this information as an initial step to develop a normal functional data base for future studies. 3. To try to determine if there is a biological substrate to the process of recalling previous auditory perceptions and if possible, suggest a locus for auditory memory. Method. Brain perfusion single photon emission computerized tomography (SPECT) evaluation was conducted: 1-2) Using auditory stimulation with pure tones in 4 volunteers with normal hearing. 3) In a patient with bilateral profound hearing loss who had auditory perception of previous musical experiences; while injected with Tc99m HMPAO while she was having the sensation of hearing a well known melody. Results. Both in the patient with auditory hallucinations and the normal controls -stimulated with pure tones- there was a statistically significant increase in perfusion in Brodmann's area 39, more intense on the right side (right to left p < 0.05). With a lesser intensity there was activation in the adjacent area 40 and there was intense activation also in the executive frontal cortex areas 6, 8, 9, and 10 of Brodmann. There was also activation of area 7 of Brodmann; an audio-visual association area; more marked on the right side in the patient and the normal stimulated controls. In the subcortical structures there was also marked activation in the patient with hallucinations in both lentiform nuclei, thalamus and caudate nuclei also more intense in the right hemisphere, 5, 4.7 and 4.2 S.D. above the mean respectively and 5, 3.3, and 3 S.D. above the normal mean in the left hemisphere respectively. Similar findings were observed in normal controls. Conclusions. After auditory stimulation with pure tones in the left ear of normal female volunteers, there is bilateral activation of area 39

  13. 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.

  14. 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.

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

    Science.gov (United States)

    Brosch, Michael; Selezneva, Elena; Scheich, Henning

    2015-03-01

    This study aimed at a deeper understanding of which cognitive and motivational aspects of tasks affect auditory cortical activity. To this end we trained two macaque monkeys to perform two different tasks on the same audiovisual stimulus and to do this with two different sizes of water rewards. The monkeys had to touch a bar after a tone had been turned on together with an LED, and to hold the bar until either the tone (auditory task) or the LED (visual task) was turned off. In 399 multiunits recorded from core fields of auditory cortex we confirmed that during task engagement neurons responded to auditory and non-auditory stimuli that were task-relevant, such as light and water. We also confirmed that firing rates slowly increased or decreased for several seconds during various phases of the tasks. Responses to non-auditory stimuli and slow firing changes were observed during both the auditory and the visual task, with some differences between them. There was also a weak task-dependent modulation of the responses to auditory stimuli. In contrast to these cognitive aspects, motivational aspects of the tasks were not reflected in the firing, except during delivery of the water reward. In conclusion, the present study supports our previous proposal that there are two response types in the auditory cortex that represent the timing and the type of auditory and non-auditory elements of a auditory tasks as well the association between elements. PMID:25728179

  16. Spectral and Temporal Acoustic Features Modulate Response Irregularities within Primary Auditory Cortex Columns.

    Directory of Open Access Journals (Sweden)

    Andres Carrasco

    Full Text Available Assemblies of vertically connected neurons in the cerebral cortex form information processing units (columns that participate in the distribution and segregation of sensory signals. Despite well-accepted models of columnar architecture, functional mechanisms of inter-laminar communication remain poorly understood. Hence, the purpose of the present investigation was to examine the effects of sensory information features on columnar response properties. Using acute recording techniques, extracellular response activity was collected from the right hemisphere of eight mature cats (felis catus. Recordings were conducted with multichannel electrodes that permitted the simultaneous acquisition of neuronal activity within primary auditory cortex columns. Neuronal responses to simple (pure tones, complex (noise burst and frequency modulated sweeps, and ecologically relevant (con-specific vocalizations acoustic signals were measured. Collectively, the present investigation demonstrates that despite consistencies in neuronal tuning (characteristic frequency, irregularities in discharge activity between neurons of individual A1 columns increase as a function of spectral (signal complexity and temporal (duration acoustic variations.

  17. Pitch-induced responses in the right auditory cortex correlate with musical ability in normal listeners.

    Science.gov (United States)

    Puschmann, Sebastian; Özyurt, Jale; Uppenkamp, Stefan; Thiel, Christiane M

    2013-10-23

    Previous work compellingly shows the existence of functional and structural differences in human auditory cortex related to superior musical abilities observed in professional musicians. In this study, we investigated the relationship between musical abilities and auditory cortex activity in normal listeners who had not received a professional musical education. We used functional MRI to measure auditory cortex responses related to auditory stimulation per se and the processing of pitch and pitch changes, which represents a prerequisite for the perception of musical sequences. Pitch-evoked responses in the right lateral portion of Heschl's gyrus were correlated positively with the listeners' musical abilities, which were assessed using a musical aptitude test. In contrast, no significant relationship was found for noise stimuli, lacking any musical information, and for responses induced by pitch changes. Our results suggest that superior musical abilities in normal listeners are reflected by enhanced neural encoding of pitch information in the auditory system. PMID:23995293

  18. Evidence for functional abnormality in the right auditory cortex during musical hallucinations.

    Science.gov (United States)

    Kasai, K; Asada, T; Yumoto, M; Takeya, J; Matsuda, H

    1999-11-13

    Right auditory cortex dysfunction during musical hallucinations occurred in an 88-year-old woman, who was otherwise cognitively intact. We assessed this phenomenon with a combination of neuromagnetic and cerebral blood-flow measurements. PMID:10568580

  19. Sensory Responses during Sleep in Primate Primary and Secondary Auditory Cortex

    OpenAIRE

    Issa, Elias B.; Wang, Xiaoqin

    2008-01-01

    Most sensory stimuli do not reach conscious perception during sleep. It has been thought that the thalamus prevents the relay of sensory information to cortex during sleep, but the consequences for cortical responses to sensory signals in this physiological state remain unclear. We recorded from two auditory cortical areas downstream of the thalamus in naturally sleeping marmoset monkeys. Single neurons in primary auditory cortex either increased or decreased their responses during sleep comp...

  20. Dynamic modulation of short term synaptic plasticity in the auditory cortex: the role of norepinephrine

    OpenAIRE

    Humberto, Salgado; Francisco, García-Oscos; Lu, Dinh; Marco, Atzori

    2010-01-01

    Norepinephrine (NE) is an important modulator of neuronal activity in the auditory cortex. Using patch-clamp recording and a pair pulse protocol on an auditory cortex slice preparation we recently demonstrated that NE affects cortical inhibition in a layer-specific manner, by decreasing apical but increasing basal inhibition onto layer II/III pyramidal cell dendrites. In the present study we used a similar protocol to investigate the dependence of noradrenergic modulation of inhibition on sti...

  1. Auditory Spatial Coding Flexibly Recruits Anterior, but Not Posterior, Visuotopic Parietal Cortex

    OpenAIRE

    Michalka, Samantha W.; Rosen, Maya L.; Kong, Lingqiang; Shinn-Cunningham, Barbara G.; Somers, David C.

    2015-01-01

    Audition and vision both convey spatial information about the environment, but much less is known about mechanisms of auditory spatial cognition than visual spatial cognition. Human cortex contains >20 visuospatial map representations but no reported auditory spatial maps. The intraparietal sulcus (IPS) contains several of these visuospatial maps, which support visuospatial attention and short-term memory (STM). Neuroimaging studies also demonstrate that parietal cortex is activated during au...

  2. A rate code for sound azimuth in monkey auditory cortex: implications for human neuroimaging studies

    OpenAIRE

    Werner-Reiss, Uri; Jennifer M Groh

    2008-01-01

    Is sound location represented in the auditory cortex of humans and monkeys? Human neuroimaging experiments have had only mixed success at demonstrating sound location sensitivity in primary auditory cortex. This is in apparent conflict with studies in monkeys and other animals, where single-unit recording studies have found stronger evidence for spatial sensitivity. Does this apparent discrepancy reflect a difference between humans and animals, or does it reflect differences in the sensitivit...

  3. Auditory Spatial Coding Flexibly Recruits Anterior, but Not Posterior, Visuotopic Parietal Cortex.

    Science.gov (United States)

    Michalka, Samantha W; Rosen, Maya L; Kong, Lingqiang; Shinn-Cunningham, Barbara G; Somers, David C

    2016-03-01

    Audition and vision both convey spatial information about the environment, but much less is known about mechanisms of auditory spatial cognition than visual spatial cognition. Human cortex contains >20 visuospatial map representations but no reported auditory spatial maps. The intraparietal sulcus (IPS) contains several of these visuospatial maps, which support visuospatial attention and short-term memory (STM). Neuroimaging studies also demonstrate that parietal cortex is activated during auditory spatial attention and working memory tasks, but prior work has not demonstrated that auditory activation occurs within visual spatial maps in parietal cortex. Here, we report both cognitive and anatomical distinctions in the auditory recruitment of visuotopically mapped regions within the superior parietal lobule. An auditory spatial STM task recruited anterior visuotopic maps (IPS2-4, SPL1), but an auditory temporal STM task with equivalent stimuli failed to drive these regions significantly. Behavioral and eye-tracking measures rule out task difficulty and eye movement explanations. Neither auditory task recruited posterior regions IPS0 or IPS1, which appear to be exclusively visual. These findings support the hypothesis of multisensory spatial processing in the anterior, but not posterior, superior parietal lobule and demonstrate that recruitment of these maps depends on auditory task demands. PMID:26656996

  4. The effect of sequence repeat time on auditory cortex stimulation during phonetic discrimination

    OpenAIRE

    Shah, J. N.; Steinhoff, S; Mirzazade, S.; Zafiris, O.; Grosse-Ruyken, M. L.; Jäncke, R. K.; Zilles, K

    2000-01-01

    Acoustic noise generated by the MR scanner gradient system during fMRI studies of auditory function is a very significant potential confound. Despite these deleterious effects, fMRI of the auditory cortex has been successful and numerous practitioners have circumvented the problem of acoustic masking noise. In the context of auditory cortex fMRI, the sequence repeat time (TR) has the effect of altering the length of time during which the scanner is quiet. Indeed, the move to whole-brain fMRI ...

  5. Hemodynamic responses in human multisensory and auditory association cortex to purely visual stimulation

    Directory of Open Access Journals (Sweden)

    Baumann Simon

    2007-02-01

    Full Text Available Abstract Background Recent findings of a tight coupling between visual and auditory association cortices during multisensory perception in monkeys and humans raise the question whether consistent paired presentation of simple visual and auditory stimuli prompts conditioned responses in unimodal auditory regions or multimodal association cortex once visual stimuli are presented in isolation in a post-conditioning run. To address this issue fifteen healthy participants partook in a "silent" sparse temporal event-related fMRI study. In the first (visual control habituation phase they were presented with briefly red flashing visual stimuli. In the second (auditory control habituation phase they heard brief telephone ringing. In the third (conditioning phase we coincidently presented the visual stimulus (CS paired with the auditory stimulus (UCS. In the fourth phase participants either viewed flashes paired with the auditory stimulus (maintenance, CS- or viewed the visual stimulus in isolation (extinction, CS+ according to a 5:10 partial reinforcement schedule. The participants had no other task than attending to the stimuli and indicating the end of each trial by pressing a button. Results During unpaired visual presentations (preceding and following the paired presentation we observed significant brain responses beyond primary visual cortex in the bilateral posterior auditory association cortex (planum temporale, planum parietale and in the right superior temporal sulcus whereas the primary auditory regions were not involved. By contrast, the activity in auditory core regions was markedly larger when participants were presented with auditory stimuli. Conclusion These results demonstrate involvement of multisensory and auditory association areas in perception of unimodal visual stimulation which may reflect the instantaneous forming of multisensory associations and cannot be attributed to sensation of an auditory event. More importantly, we are able

  6. The olivocochlear reflex strength and cochlear sensitivity are independently modulated by auditory cortex microstimulation.

    Science.gov (United States)

    Dragicevic, Constantino D; Aedo, Cristian; León, Alex; Bowen, Macarena; Jara, Natalia; Terreros, Gonzalo; Robles, Luis; Delano, Paul H

    2015-04-01

    In mammals, efferent projections to the cochlear receptor are constituted by olivocochlear (OC) fibers that originate in the superior olivary complex. Medial and lateral OC neurons make synapses with outer hair cells and with auditory nerve fibers, respectively. In addition to the OC system, there are also descending projections from the auditory cortex that are directed towards the thalamus, inferior colliculus, cochlear nucleus, and superior olivary complex. Olivocochlear function can be assessed by measuring a brainstem reflex mediated by auditory nerve fibers, cochlear nucleus neurons, and OC fibers. Although it is known that the OC reflex is activated by contralateral acoustic stimulation and produces a suppression of cochlear responses, the influence of cortical descending pathways in the OC reflex is largely unknown. Here, we used auditory cortex electrical microstimulation in chinchillas to study a possible cortical modulation of cochlear and auditory nerve responses to tones in the absence and presence of contralateral noise. We found that cortical microstimulation produces two different peripheral modulations: (i) changes in cochlear sensitivity evidenced by amplitude modulation of cochlear microphonics and auditory nerve compound action potentials and (ii) enhancement or suppression of the OC reflex strength as measured by auditory nerve responses, which depended on the intersubject variability of the OC reflex. Moreover, both corticofugal effects were not correlated, suggesting the presence of two functionally different efferent pathways. These results demonstrate that auditory cortex electrical microstimulation independently modulates the OC reflex strength and cochlear sensitivity. PMID:25663383

  7. Representation of auditory-filter phase characteristics in the cortex of human listeners

    DEFF Research Database (Denmark)

    Rupp, A.; Sieroka, N.; Gutschalk, A.;

    2008-01-01

    Harmonic tone complexes with component phases, adjusted using a variant of a method proposed by Schroeder, can produce pure-tone masked thresholds differing by >20 dB. This phenomenon has been qualitatively explained by the phase characteristics of the auditory filters on the basilar membrane......, which differently affect the flat envelopes of the Schroeder-phase maskers. We examined the influence of auditory-filter phase characteristics on the neural representation in the auditory cortex by investigating cortical auditory evoked fields ( AEFs). We found that the P1m component exhibited larger...

  8. The Development and Activity-Dependent Expression of Aggrecan in the Cat Visual Cortex

    OpenAIRE

    Kind, P. C.; Sengpiel, F.; Beaver, C. J.; Crocker-Buque, A.; Kelly, G. M.; R. T. Matthews; Mitchell, D E

    2012-01-01

    The Cat-301 monoclonal antibody identifies aggrecan, a chondroitin sulfate proteoglycan in the cat visual cortex and dorsal lateral geniculate nucleus (dLGN). During development, aggrecan expression increases in the dLGN with a time course that matches the decline in plasticity. Moreover, examination of tissue from selectively visually deprived cats shows that expression is activity dependent, suggesting a role for aggrecan in the termination of the sensitive period. Here, we demonstrate for ...

  9. 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

  10. Dual streams of auditory afferents target multiple domains in the primate prefrontal cortex

    Science.gov (United States)

    Romanski, L. M.; Tian, B.; Fritz, J.; Mishkin, M.; Goldman-Rakic, P. S.; Rauschecker, J. P.

    2009-01-01

    ‘What’ and ‘where’ visual streams define ventrolateral object and dorsolateral spatial processing domains in the prefrontal cortex of nonhuman primates. We looked for similar streams for auditory–prefrontal connections in rhesus macaques by combining microelectrode recording with anatomical tract-tracing. Injection of multiple tracers into physiologically mapped regions AL, ML and CL of the auditory belt cortex revealed that anterior belt cortex was reciprocally connected with the frontal pole (area 10), rostral principal sulcus (area 46) and ventral prefrontal regions (areas 12 and 45), whereas the caudal belt was mainly connected with the caudal principal sulcus (area 46) and frontal eye fields (area 8a). Thus separate auditory streams originate in caudal and rostral auditory cortex and target spatial and non-spatial domains of the frontal lobe, respectively. PMID:10570492

  11. Functional maps of human auditory cortex: effects of acoustic features and attention.

    Directory of Open Access Journals (Sweden)

    David L Woods

    Full Text Available BACKGROUND: While human auditory cortex is known to contain tonotopically organized auditory cortical fields (ACFs, little is known about how processing in these fields is modulated by other acoustic features or by attention. METHODOLOGY/PRINCIPAL FINDINGS: We used functional magnetic resonance imaging (fMRI and population-based cortical surface analysis to characterize the tonotopic organization of human auditory cortex and analyze the influence of tone intensity, ear of delivery, scanner background noise, and intermodal selective attention on auditory cortex activations. Medial auditory cortex surrounding Heschl's gyrus showed large sensory (unattended activations with two mirror-symmetric tonotopic fields similar to those observed in non-human primates. Sensory responses in medial regions had symmetrical distributions with respect to the left and right hemispheres, were enlarged for tones of increased intensity, and were enhanced when sparse image acquisition reduced scanner acoustic noise. Spatial distribution analysis suggested that changes in tone intensity shifted activation within isofrequency bands. Activations to monaural tones were enhanced over the hemisphere contralateral to stimulation, where they produced activations similar to those produced by binaural sounds. Lateral regions of auditory cortex showed small sensory responses that were larger in the right than left hemisphere, lacked tonotopic organization, and were uninfluenced by acoustic parameters. Sensory responses in both medial and lateral auditory cortex decreased in magnitude throughout stimulus blocks. Attention-related modulations (ARMs were larger in lateral than medial regions of auditory cortex and appeared to arise primarily in belt and parabelt auditory fields. ARMs lacked tonotopic organization, were unaffected by acoustic parameters, and had distributions that were distinct from those of sensory responses. Unlike the gradual adaptation seen for sensory responses

  12. 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

  13. Early Hearing-Impairment Results in Crossmodal Reorganization of Ferret Core Auditory Cortex

    Directory of Open Access Journals (Sweden)

    M. Alex Meredith

    2012-01-01

    Full Text Available Numerous investigations of cortical crossmodal plasticity, most often in congenital or early-deaf subjects, have indicated that secondary auditory cortical areas reorganize to exhibit visual responsiveness while the core auditory regions are largely spared. However, a recent study of adult-deafened ferrets demonstrated that core auditory cortex was reorganized by the somatosensory modality. Because adult animals have matured beyond their critical period of sensory development and plasticity, it was not known if adult-deafening and early-deafening would generate the same crossmodal results. The present study used young, ototoxically-lesioned ferrets (n=3 that, after maturation (avg. = 173 days old, showed significant hearing deficits (avg. threshold = 72 dB SPL. Recordings from single-units (n=132 in core auditory cortex showed that 72% were activated by somatosensory stimulation (compared to 1% in hearing controls. In addition, tracer injection into early hearing-impaired core auditory cortex labeled essentially the same auditory cortical and thalamic projection sources as seen for injections in the hearing controls, indicating that the functional reorganization was not the result of new or latent projections to the cortex. These data, along with similar observations from adult-deafened and adult hearing-impaired animals, support the recently proposed brainstem theory for crossmodal plasticity induced by hearing loss.

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    Martina Wengenroth

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

  16. A unified framework for the organisation of the primate auditory cortex

    Directory of Open Access Journals (Sweden)

    Simon Baumann

    2013-04-01

    Full Text Available In nonhuman primates a scheme for the organisation of the auditory cortex is frequently used to localise auditory processes. The scheme allows a common basis for comparison of functional organisation across nonhuman primate species. However, although a body of functional and structural data in nonhuman primates supports an accepted scheme of nearly a dozen neighbouring functional areas, can this scheme be directly applied to humans? Attempts to expand the scheme of auditory cortical fields in humans have been severely hampered by a recent controversy about the organisation of tonotopic maps in humans, centred on two different models with radically different organisation. We point out observations that reconcile the previous models and suggest a distinct model in which the human cortical organisation is much more like that of other primates. This unified framework allows a more robust and detailed comparison of auditory cortex organisation across primate species including humans.

  17. Different patterns of auditory cortex activation revealed by functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    In the last few years, functional Magnetic Resonance Imaging (fMRI) has been widely accepted as an effective tool for mapping brain activities in both the sensorimotor and the cognitive field. The present work aims to assess the possibility of using fMRI methods to study the cortical response to different acoustic stimuli. Furthermore, we refer to recent data collected at Frankfurt University on the cortical pattern of auditory hallucinations. Healthy subjects showed broad bilateral activation, mostly located in the transverse gyrus of Heschl. The analysis of the cortical activation induced by different stimuli has pointed out a remarkable difference in the spatial and temporal features of the auditory cortex response to pulsed tones and pure tones. The activated areas during episodes of auditory hallucinations match the location of primary auditory cortex as defined in control measurements with the same patients and in the experiments on healthy subjects. (authors)

  18. Proximal vocal threat recruits the right voice-sensitive auditory cortex.

    Science.gov (United States)

    Ceravolo, Leonardo; Frühholz, Sascha; Grandjean, Didier

    2016-05-01

    The accurate estimation of the proximity of threat is important for biological survival and to assess relevant events of everyday life. We addressed the question of whether proximal as compared with distal vocal threat would lead to a perceptual advantage for the perceiver. Accordingly, we sought to highlight the neural mechanisms underlying the perception of proximal vs distal threatening vocal signals by the use of functional magnetic resonance imaging. Although we found that the inferior parietal and superior temporal cortex of human listeners generally decoded the spatial proximity of auditory vocalizations, activity in the right voice-sensitive auditory cortex was specifically enhanced for proximal aggressive relative to distal aggressive voices as compared with neutral voices. Our results shed new light on the processing of imminent danger signaled by proximal vocal threat and show the crucial involvement of the right mid voice-sensitive auditory cortex in such processing. PMID:26746180

  19. The Olivocochlear Reflex Strength and Cochlear Sensitivity are Independently Modulated by Auditory Cortex Microstimulation

    OpenAIRE

    Dragicevic, Constantino D.; Aedo, Cristian; León, Alex; Bowen, Macarena; Jara, Natalia; Terreros, Gonzalo; Robles, Luis; Delano, Paul H.

    2015-01-01

    In mammals, efferent projections to the cochlear receptor are constituted by olivocochlear (OC) fibers that originate in the superior olivary complex. Medial and lateral OC neurons make synapses with outer hair cells and with auditory nerve fibers, respectively. In addition to the OC system, there are also descending projections from the auditory cortex that are directed towards the thalamus, inferior colliculus, cochlear nucleus, and superior olivary complex. Olivocochlear function can be as...

  20. Age-related changes of structures in cerebellar cortex of cat

    Indian Academy of Sciences (India)

    Changzheng Zhang; Tianmiao Hua; Zaiman Zhu; Xun Luo

    2006-03-01

    We studied the structures of the cerebellar cortex of young adult and old cats for age-related changes, which were statistically analysed. Nissl staining was used to visualize the cortical neurons. The immunohistochemical method was used to display glial fibrillary acidic protein (GFAP)-immunoreactive (IR) astrocytes and neurofilament-immunoreactive (NF-IR) neurons. Under the microscope, the thickness of the cerebellar cortex was measured; and the density of neurons in all the layers as well as that of GFAP-IR cells in the granular layer was analysed. Compared with young adult cats, the thickness of the molecular layer and total cerebellar cortex was significantly decreased in old cats, and that of the granular layer increased. The density of neurons in each layer was significantly lower in old cats than in young adult ones. Astrocytes in old cats were significantly denser than in young adult ones, and accompanied by evident hypertrophy of the cell bodies and enhanced immunoreaction of GFAP substance. Purkinje cells (PCs) in old cats showed much fewer NF-IR dendrites than those in young adults. The above findings indicate a loss of neurons and decrease in the number of dendrites of the PCs in the aged cerebellar cortex, which might underlie the functional decline of afferent efficacy and information integration in the senescent cerebellum. An age-dependent enhancement of activity of the astrocytes may exert a protective effect on neurons in the aged cerebellum.

  1. Listen to Yourself: The Medial Prefrontal Cortex Modulates Auditory Alpha Power During Speech Preparation.

    Science.gov (United States)

    Müller, Nadia; Leske, Sabine; Hartmann, Thomas; Szebényi, Szabolcs; Weisz, Nathan

    2015-11-01

    How do we process stimuli that stem from the external world and stimuli that are self-generated? In the case of voice perception it has been shown that evoked activity elicited by self-generated sounds is suppressed compared with the same sounds played-back externally. We here wanted to reveal whether neural excitability of the auditory cortex-putatively reflected in local alpha band power--is modulated already prior to speech onset, and which brain regions may mediate such a top-down preparatory response. In the left auditory cortex we show that the typical alpha suppression found when participants prepare to listen disappears when participants expect a self-spoken sound. This suggests an inhibitory adjustment of auditory cortical activity already before sound onset. As a second main finding we demonstrate that the medial prefrontal cortex, a region known for self-referential processes, mediates these condition-specific alpha power modulations. This provides crucial insights into how higher-order regions prepare the auditory cortex for the processing of self-generated sounds. Furthermore, the mechanism outlined could provide further explanations to self-referential phenomena, such as "tickling yourself". Finally, it has implications for the so-far unsolved question of how auditory alpha power is mediated by higher-order regions in a more general sense. PMID:24904068

  2. Quantifying and comparing the pattern of thalamic and cortical projections to the posterior auditory field in hearing and deaf cats.

    Science.gov (United States)

    Butler, Blake E; Chabot, Nicole; Lomber, Stephen G

    2016-10-15

    Following sensory loss, compensatory crossmodal reorganization occurs such that the remaining modalities are functionally enhanced. For example, behavioral evidence suggests that peripheral visual localization is better in deaf than in normal hearing animals, and that this enhancement is mediated by recruitment of the posterior auditory field (PAF), an area that is typically involved in localization of sounds in normal hearing animals. To characterize the anatomical changes that underlie this phenomenon, we identified the thalamic and cortical projections to the PAF in hearing cats and those with early- and late-onset deafness. The retrograde tracer biotinylated dextran amine was deposited in the PAF unilaterally, to label cortical and thalamic afferents. Following early deafness, there was a significant decrease in callosal projections from the contralateral PAF. Late-deaf animals showed small-scale changes in projections from one visual cortical area, the posterior ectosylvian field (EPp), and the multisensory zone (MZ). With the exception of these minor differences, connectivity to the PAF was largely similar between groups, with the principle projections arising from the primary auditory cortex (A1) and the ventral division of the medial geniculate body (MGBv). This absence of large-scale connectional change suggests that the functional reorganization that follows sensory loss results from changes in synaptic strength and/or unmasking of subthreshold intermodal connections. J. Comp. Neurol. 524:3042-3063, 2016. © 2016 Wiley Periodicals, Inc. PMID:27019080

  3. 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...

  4. 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

  5. Formation and disruption of tonotopy in a large-scale model of the auditory cortex

    Czech Academy of Sciences Publication Activity Database

    Tomková, M.; Tomek, J.; Novák, Ondřej; Zelenka, Ondřej; Syka, Josef; Brom, C.

    2015-01-01

    Roč. 39, č. 2 (2015), s. 131-153. ISSN 0929-5313 R&D Projects: GA ČR(CZ) GAP303/12/1347 Institutional support: RVO:68378041 Keywords : auditory cortex * large-scale model * spiking neuron * oscillation * STDP * tonotopy Subject RIV: FH - Neurology Impact factor: 1.739, year: 2014

  6. Processing of acoustic motion in the auditory cortex of the rufous horseshoe bat, Rhinolophus rouxi

    OpenAIRE

    Firzlaff, Uwe

    2001-01-01

    This study investigated the representation of acoustic motion in different fields of auditory cortex of the rufous horseshoe bat, Rhinolophus rouxi. Motion in horizontal direction (azimuth) was simulated using successive stimuli with dynamically changing interaural intensity differences presented via earphones. The mechanisms underlying a specific sensitivity of neurons to the direction of motion were investigated using microiontophoretic application of γ-aminobutyric acid (GAB...

  7. The response properties of neurons in different fields of the auditory cortex in the rat

    Czech Academy of Sciences Publication Activity Database

    Profant, Oliver; Burianová, Jana; Syka, Josef

    2013-01-01

    Roč. 296, February (2013), s. 51-59. ISSN 0378-5955 R&D Projects: GA ČR(CZ) GAP303/12/1347; GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:68378041 Keywords : auditory cortex * fequency representation * axon terminals Subject RIV: FH - Neurology Impact factor: 2.848, year: 2013

  8. Inactivation of the left auditory cortex impairs temporal discrimination in the rat

    Czech Academy of Sciences Publication Activity Database

    Rybalko, Natalia; Šuta, Daniel; Popelář, Jiří; Syka, Josef

    2010-01-01

    Roč. 209, č. 1 (2010), s. 123-130. ISSN 0166-4328 R&D Projects: GA ČR GA309/07/1336; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390512 Keywords : auditory cortex * temporal discrimination * hemispheric lateralization Subject RIV: FH - Neurology Impact factor: 3.393, year: 2010

  9. Effect of a temporary inactivation of the auditory cortex on time resolution in the rat

    Czech Academy of Sciences Publication Activity Database

    Rybalko, Natalia; Syka, Josef

    Tübingen : IEB, 2005. s. 176. [42nd workshop on Inner Ear Biology. 18.9.2005-20.9.2005, Tübingen] R&D Projects: GA MZd NR8113; GA ČR GA309/04/1074 Institutional research plan: CEZ:AV0Z50390512 Keywords : auditory cortex Subject RIV: FH - Neurology

  10. Asymmetry in primary auditory cortex activity in tinnitus patients and controls

    NARCIS (Netherlands)

    Geven, L. I.; de Kleine, E.; Willemsen, A. T. M.; van Dijk, P.

    2014-01-01

    Tinnitus is a bothersome phantom sound percept and its neural correlates are not yet disentangled. Previously published papers, using [(18)F]-fluoro-deoxyglucose positron emission tomography (FDG-PET), have suggested an increased metabolism in the left primary auditory cortex in tinnitus patients. T

  11. Metabolic changes in the auditory cortex in presbycusis demonstrated by MR spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Profant, Oliver; Balogová, Zuzana; Dezortová, M.; Wagnerová, D.; Hájek, M.; Syka, Josef

    2013-01-01

    Roč. 48, č. 8 (2013), s. 795-800. ISSN 0531-5565 R&D Projects: GA ČR GAP304/10/1872 Grant ostatní: GA MZd(CZ) 00023001IKEM Institutional support: RVO:68378041 Keywords : Presbycusis * Auditory cortex * MR spectroscopy Subject RIV: FH - Neurology Impact factor: 3.529, year: 2013

  12. Effects of damage to auditory cortex on the discrimination of speech sounds by rats

    Czech Academy of Sciences Publication Activity Database

    Floody, O. R.; Ouda, Ladislav; Porter, B. A.; Kilgard, M. P.

    2010-01-01

    Roč. 101, č. 2 (2010), s. 260-268. ISSN 0031-9384 R&D Projects: GA ČR GA309/07/1336 Institutional research plan: CEZ:AV0Z50390703 Keywords : auditory cortex * brain lesions * prepulse inhibition Subject RIV: FH - Neurology Impact factor: 2.891, year: 2010

  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. Retrosplenial Cortex Is Required for the Retrieval of Remote Memory for Auditory Cues

    Science.gov (United States)

    Todd, Travis P.; Mehlman, Max L.; Keene, Christopher S.; DeAngeli, Nicole E.; Bucci, David J.

    2016-01-01

    The retrosplenial cortex (RSC) has a well-established role in contextual and spatial learning and memory, consistent with its known connectivity with visuo-spatial association areas. In contrast, RSC appears to have little involvement with delay fear conditioning to an auditory cue. However, all previous studies have examined the contribution of…

  15. Cooling of the auditory cortex modifies neuronal activity in the inferior colliculus in rats

    Czech Academy of Sciences Publication Activity Database

    Popelář, Jiří; Šuta, Daniel; Lindovský, Jiří; Bureš, Zbyněk; Pysaněnko, Kateryna; Chumak, Tetyana; Syka, Josef

    2016-01-01

    Roč. 332, feb (2016), s. 7-16. ISSN 0378-5955 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GAP303/12/1347 Institutional support: RVO:68378041 Keywords : auditory cortex * cooling * cortical inactivation * efferent system Subject RIV: ED - Physiology Impact factor: 2.968, year: 2014

  16. Variability and information content in auditory cortex spike trains during an interval-discrimination task.

    Science.gov (United States)

    Abolafia, Juan M; Martinez-Garcia, M; Deco, G; Sanchez-Vives, M V

    2013-11-01

    Processing of temporal information is key in auditory processing. In this study, we recorded single-unit activity from rat auditory cortex while they performed an interval-discrimination task. The animals had to decide whether two auditory stimuli were separated by either 150 or 300 ms and nose-poke to the left or to the right accordingly. The spike firing of single neurons in the auditory cortex was then compared in engaged vs. idle brain states. We found that spike firing variability measured with the Fano factor was markedly reduced, not only during stimulation, but also in between stimuli in engaged trials. We next explored if this decrease in variability was associated with an increased information encoding. Our information theory analysis revealed increased information content in auditory responses during engagement compared with idle states, in particular in the responses to task-relevant stimuli. Altogether, we demonstrate that task-engagement significantly modulates coding properties of auditory cortical neurons during an interval-discrimination task. PMID:23945780

  17. Speech sound discrimination training improves auditory cortex responses in a rat model of autism

    Directory of Open Access Journals (Sweden)

    Crystal T Engineer

    2014-08-01

    Full Text Available Children with autism often have language impairments and degraded cortical responses to speech. Extensive behavioral interventions can improve language outcomes and cortical responses. Prenatal exposure to the antiepileptic drug valproic acid (VPA increases the risk for autism and language impairment. Prenatal exposure to VPA also causes weaker and delayed auditory cortex responses in rats. In this study, we document speech sound discrimination ability in VPA exposed rats and document the effect of extensive speech training on auditory cortex responses. VPA exposed rats were significantly impaired at consonant, but not vowel, discrimination. Extensive speech training resulted in both stronger and faster anterior auditory field responses compared to untrained VPA exposed rats, and restored responses to control levels. This neural response improvement generalized to non-trained sounds. The rodent VPA model of autism may be used to improve the understanding of speech processing in autism and contribute to improving language outcomes.

  18. Multimodal Lexical Processing in Auditory Cortex Is Literacy Skill Dependent

    OpenAIRE

    McNorgan, Chris; Awati, Neha; Desroches, Amy S.; Booth, James R.

    2013-01-01

    Literacy is a uniquely human cross-modal cognitive process wherein visual orthographic representations become associated with auditory phonological representations through experience. Developmental studies provide insight into how experience-dependent changes in brain organization influence phonological processing as a function of literacy. Previous investigations show a synchrony-dependent influence of letter presentation on individual phoneme processing in superior temporal sulcus; others d...

  19. 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

  20. 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.

  1. Functional MR imaging of cerebral auditory cortex with linguistic and non-linguistic stimulation: preliminary study

    International Nuclear Information System (INIS)

    To obtain preliminary data for understanding the central auditory neural pathway by means of functional MR imaging (fMRI) of the cerebral auditory cortex during linguistic and non-linguistic auditory stimulation. In three right-handed volunteers we conducted fMRI of auditory cortex stimulation at 1.5 T using a conventional gradient-echo technique (TR/TE/flip angle: 80/60/40 deg). Using a pulsed tone of 1000 Hz and speech as non-linguistic and linguistic auditory stimuli, respectively, images-including those of the superior temporal gyrus of both hemispheres-were obtained in sagittal plases. Both stimuli were separately delivered binaurally or monoaurally through a plastic earphone. Images were activated by processing with homemade software. In order to analyze patterns of auditory cortex activation according to type of stimulus and which side of the ear was stimulated, the number and extent of activated pixels were compared between both temporal lobes. Biaural stimulation led to bilateral activation of the superior temporal gyrus, while monoaural stimulation led to more activation in the contralateral temporal lobe than in the ipsilateral. A trend toward slight activation of the left (dominant) temporal lobe in ipsilateral stimulation, particularly with a linguistic stimulus, was observed. During both biaural and monoaural stimulation, a linguistic stimulus produced more widespread activation than did a non-linguistic one. The superior temporal gyri of both temporal lobes are associated with acoustic-phonetic analysis, and the left (dominant) superior temporal gyrus is likely to play a dominant role in this processing. For better understanding of physiological and pathological central auditory pathways, further investigation is needed

  2. Simultaneous recording of rat auditory cortex and thalamus via a titanium-based, microfabricated, microelectrode device

    Science.gov (United States)

    McCarthy, P. T.; Rao, M. P.; Otto, K. J.

    2011-08-01

    Direct recording from sequential processing stations within the brain has provided opportunity for enhancing understanding of important neural circuits, such as the corticothalamic loops underlying auditory, visual, and somatosensory processing. However, the common reliance upon microwire-based electrodes to perform such recordings often necessitates complex surgeries and increases trauma to neural tissues. This paper reports the development of titanium-based, microfabricated, microelectrode devices designed to address these limitations by allowing acute recording from the thalamic nuclei and associated cortical sites simultaneously in a minimally invasive manner. In particular, devices were designed to simultaneously probe rat auditory cortex and auditory thalamus, with the intent of recording auditory response latencies and isolated action potentials within the separate anatomical sites. Details regarding the design, fabrication, and characterization of these devices are presented, as are preliminary results from acute in vivo recording.

  3. Measuring the dynamics of neural responses in primary auditory cortex

    OpenAIRE

    Depireux, Didier A; Simon, Jonathan Z.; Shamma, Shihab A.

    1998-01-01

    We review recent developments in the measurement of the dynamics of the response properties of auditory cortical neurons to broadband sounds, which is closely related to the perception of timbre. The emphasis is on a method that characterizes the spectro-temporal properties of single neurons to dynamic, broadband sounds, akin to the drifting gratings used in vision. The method treats the spectral and temporal aspects of the response on an equal footing.

  4. Processing of spatial sounds in human auditory cortex during visual, discrimination and 2-back tasks

    Directory of Open Access Journals (Sweden)

    TeemuRinne

    2014-07-01

    Full Text Available Previous imaging studies on the brain mechanisms of spatial hearing have mainly focused on sounds varying in the horizontal plane. In this study, we compared activations in human auditory cortex (AC and adjacent inferior parietal lobule (IPL to sounds varying in horizontal location, distance, or space (i.e., different rooms. In order to investigate both stimulus-dependent and task-dependent activations, these sounds were presented during visual discrimination, auditory discrimination, and auditory 2-back memory tasks. Consistent with previous studies, activations in AC were modulated by the auditory tasks. During both auditory and visual tasks, activations in AC were stronger to sounds varying in horizontal location than along other feature dimensions. However, in IPL, this enhancement was detected only during auditory tasks. Based on these results, we argue that IPL is not primarily involved in stimulus-level spatial analysis but that it may represent such information for more general processing when relevant to an active auditory task.

  5. Traversing Scales: Large Scale Simulation of the Cat Cortex Using Single Neuron Models

    Czech Academy of Sciences Publication Activity Database

    Vejmelka, Martin; Fründ, I.; Pillai, A.

    Berlin: Springer-Verlag, 2008 - (Graben, P.; Zhou, C.; Thiel, M.; Kurths, J.), s. 331-342. (Understanding Complex Systems). ISBN 978-3-540-73158-0 Institutional research plan: CEZ:AV0Z10300504 Keywords : cat cortex * large scale simulation * single neuron models * spiking models * complex networks * neural connectivity * signal propagation Subject RIV: IN - Informatics, Computer Science

  6. Delayed-alternation performance after selective lesions within the prefrontal cortex of the cat.

    Science.gov (United States)

    Markowitsch, H J; Pritzel, M; Kessler, J; Guldin, W; Freeman, R B

    1980-02-01

    On the basis of new neuroanatomical findings on relationships between subregions of the mediodorsal thalamic nucleus and the prefrontal cortex of the cat, it was attempted to investigate the relative importance of prefrontal subfields with the aim of obtaining evidence in favor of a functional inequality of different prefrontal subfields. Four areas, named presylvian (PRS), proreal (PR), dorsomedial (DM), and orbito-insular (OI) sectors, were ablated successfully in 30 adult animals. Performance of a 10-sec delayed-alternation task was compared pre- and postoperatively. Furthermore, most of the cats had to learn an extension of this task postoperatively, using a 20-sec delay period, and lastly, these animals were subjected to an extinction test. Significant performance differences were obtained between cats of different groups in all three tasks. Lesions of subregion PR, and even more of subregion PRS, led to severe behavioral deterioration, whereas lesions of subregion OI were without effect, when compared with the behavior of a sham-operated control group. PRS-cats, furthermore, showed motor disturbances during the first postoperative week. The results obtained suggest that it is possible to subdivide the cat's prefrontal cortex functionally. In addition, it is hypothesized that behavioral changes in cats of groups PRS and PR are due to an inability to use kinesthetic information properly. PMID:7284081

  7. Formation and disruption of tonotopy in a large-scale model of the auditory cortex.

    Science.gov (United States)

    Tomková, Markéta; Tomek, Jakub; Novák, Ondřej; Zelenka, Ondřej; Syka, Josef; Brom, Cyril

    2015-10-01

    There is ample experimental evidence describing changes of tonotopic organisation in the auditory cortex due to environmental factors. In order to uncover the underlying mechanisms, we designed a large-scale computational model of the auditory cortex. The model has up to 100 000 Izhikevich's spiking neurons of 17 different types, almost 21 million synapses, which are evolved according to Spike-Timing-Dependent Plasticity (STDP) and have an architecture akin to existing observations. Validation of the model revealed alternating synchronised/desynchronised states and different modes of oscillatory activity. We provide insight into these phenomena via analysing the activity of neuronal subtypes and testing different causal interventions into the simulation. Our model is able to produce experimental predictions on a cell type basis. To study the influence of environmental factors on the tonotopy, different types of auditory stimulations during the evolution of the network were modelled and compared. We found that strong white noise resulted in completely disrupted tonotopy, which is consistent with in vivo experimental observations. Stimulation with pure tones or spontaneous activity led to a similar degree of tonotopy as in the initial state of the network. Interestingly, weak white noise led to a substantial increase in tonotopy. As the STDP was the only mechanism of plasticity in our model, our results suggest that STDP is a sufficient condition for the emergence and disruption of tonotopy under various types of stimuli. The presented large-scale model of the auditory cortex and the core simulator, SUSNOIMAC, have been made publicly available. PMID:26344164

  8. Neural correlates of short-term memory in primate auditory cortex

    Directory of Open Access Journals (Sweden)

    JamesBigelow

    2014-08-01

    Full Text Available Behaviorally-relevant sounds such as conspecific vocalizations are often available for only a brief amount of time; thus, goal-directed behavior frequently depends on auditory short-term memory (STM. Despite its ecological significance, the neural processes underlying auditory STM remain poorly understood. To investigate the role of the auditory cortex in STM, single- and multi-unit activity was recorded from the primary auditory cortex (A1 of two monkeys performing an auditory STM task using simple and complex sounds. Each trial consisted of a sample and test stimulus separated by a 5-s retention interval. A brief wait period followed the test stimulus, after which subjects pressed a button if the sounds were identical (match trials or withheld button presses if they were different (nonmatch trials. A number of units exhibited significant changes in firing rate for portions of the retention interval, although these changes were rarely sustained. Instead, they were most frequently observed during the early and late portions of the retention interval, with inhibition being observed more frequently than excitation. At the population level, responses elicited on match trials were briefly suppressed early in the sound period relative to nonmatch trials. However, during the latter portion of the sound, firing rates increased significantly for match trials and remained elevated throughout the wait period. Related patterns of activity were observed in prior experiments from our lab in the dorsal temporal pole (dTP and prefrontal cortex (PFC of the same animals. The data suggest that early match suppression occurs in both A1 and the dTP, whereas later match enhancement occurs first in the PFC, followed by A1 and later in dTP. Because match enhancement occurs first in the PFC, we speculate that enhancement observed in A1 and dTP may reflect top-down feedback. Overall, our findings suggest that A1 forms part of the larger neural system recruited during

  9. 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...

  10. Neural Biomarkers for Dyslexia, ADHD, and ADD in the Auditory Cortex of Children.

    Science.gov (United States)

    Serrallach, Bettina; Groß, Christine; Bernhofs, Valdis; Engelmann, Dorte; Benner, Jan; Gündert, Nadine; Blatow, Maria; Wengenroth, Martina; Seitz, Angelika; Brunner, Monika; Seither, Stefan; Parncutt, Richard; Schneider, Peter; Seither-Preisler, Annemarie

    2016-01-01

    Dyslexia, attention deficit hyperactivity disorder (ADHD), and attention deficit disorder (ADD) show distinct clinical profiles that may include auditory and language-related impairments. Currently, an objective brain-based diagnosis of these developmental disorders is still unavailable. We investigated the neuro-auditory systems of dyslexic, ADHD, ADD, and age-matched control children (N = 147) using neuroimaging, magnetencephalography and psychoacoustics. All disorder subgroups exhibited an oversized left planum temporale and an abnormal interhemispheric asynchrony (10-40 ms) of the primary auditory evoked P1-response. Considering right auditory cortex morphology, bilateral P1 source waveform shapes, and auditory performance, the three disorder subgroups could be reliably differentiated with outstanding accuracies of 89-98%. We therefore for the first time provide differential biomarkers for a brain-based diagnosis of dyslexia, ADHD, and ADD. The method allowed not only allowed for clear discrimination between two subtypes of attentional disorders (ADHD and ADD), a topic controversially discussed for decades in the scientific community, but also revealed the potential for objectively identifying comorbid cases. Noteworthy, in children playing a musical instrument, after three and a half years of training the observed interhemispheric asynchronies were reduced by about 2/3, thus suggesting a strong beneficial influence of music experience on brain development. These findings might have far-reaching implications for both research and practice and enable a profound understanding of the brain-related etiology, diagnosis, and musically based therapy of common auditory-related developmental disorders and learning disabilities. PMID:27471442

  11. Neural Biomarkers for Dyslexia, ADHD, and ADD in the Auditory Cortex of Children

    Science.gov (United States)

    Serrallach, Bettina; Groß, Christine; Bernhofs, Valdis; Engelmann, Dorte; Benner, Jan; Gündert, Nadine; Blatow, Maria; Wengenroth, Martina; Seitz, Angelika; Brunner, Monika; Seither, Stefan; Parncutt, Richard; Schneider, Peter; Seither-Preisler, Annemarie

    2016-01-01

    Dyslexia, attention deficit hyperactivity disorder (ADHD), and attention deficit disorder (ADD) show distinct clinical profiles that may include auditory and language-related impairments. Currently, an objective brain-based diagnosis of these developmental disorders is still unavailable. We investigated the neuro-auditory systems of dyslexic, ADHD, ADD, and age-matched control children (N = 147) using neuroimaging, magnetencephalography and psychoacoustics. All disorder subgroups exhibited an oversized left planum temporale and an abnormal interhemispheric asynchrony (10–40 ms) of the primary auditory evoked P1-response. Considering right auditory cortex morphology, bilateral P1 source waveform shapes, and auditory performance, the three disorder subgroups could be reliably differentiated with outstanding accuracies of 89–98%. We therefore for the first time provide differential biomarkers for a brain-based diagnosis of dyslexia, ADHD, and ADD. The method allowed not only allowed for clear discrimination between two subtypes of attentional disorders (ADHD and ADD), a topic controversially discussed for decades in the scientific community, but also revealed the potential for objectively identifying comorbid cases. Noteworthy, in children playing a musical instrument, after three and a half years of training the observed interhemispheric asynchronies were reduced by about 2/3, thus suggesting a strong beneficial influence of music experience on brain development. These findings might have far-reaching implications for both research and practice and enable a profound understanding of the brain-related etiology, diagnosis, and musically based therapy of common auditory-related developmental disorders and learning disabilities. PMID:27471442

  12. Altered Neural Responses to Sounds in Primate Primary Auditory Cortex during Slow-Wave Sleep

    OpenAIRE

    Issa, Elias B.; Wang, Xiaoqin

    2011-01-01

    How sounds are processed by the brain during sleep is an important question for understanding how we perceive the sensory environment in this unique behavioral state. While human behavioral data have indicated selective impairments of sound processing during sleep, brain imaging and neurophysiology studies have reported that overall neural activity in auditory cortex during sleep is surprisingly similar to that during wakefulness. This responsiveness to external stimuli leaves open the questi...

  13. Discrimination of brief speech sounds is impaired in rats with auditory cortex lesions

    OpenAIRE

    Porter, Benjamin A.; Rosenthal, Tara R.; Ranasinghe, Kamalini G.; Kilgard, Michael P.

    2010-01-01

    Auditory cortex (AC) lesions impair complex sound discrimination. However, a recent study demonstrated spared performance on an acoustic startle response test of speech discrimination following AC lesions (Floody et al., 2010). The current study reports the effects of AC lesions on two operant speech discrimination tasks. AC lesions caused a modest and quickly recovered impairment in the ability of rats to discriminate consonant-vowel-consonant speech sounds. This result seems to suggest that...

  14. Integration of Auditory and Visual Communication Information in the Primate Ventrolateral Prefrontal Cortex

    OpenAIRE

    Sugihara, T.; Diltz, M. D.; Averbeck, B. B.; Romanski, L. M.

    2006-01-01

    The integration of auditory and visual stimuli is crucial for recognizing objects, communicating effectively, and navigating through our complex world. Although the frontal lobes are involved in memory, communication, and language, there has been no evidence that the integration of communication information occurs at the single-cell level in the frontal lobes. Here, we show that neurons in the macaque ventrolateral prefrontal cortex (VLPFC) integrate audiovisual communication stimuli. The mul...

  15. Tracking cortical entrainment in neural activity: Auditory processes in human temporal cortex

    OpenAIRE

    Thwaites, Andrew; Nimmo-Smith, Ian; Fonteneau, Elisabeth; Patterson, Roy D.; Buttery, Paula; Marslen-Wilson, William D.

    2015-01-01

    A primary objective for cognitive neuroscience is to identify how features of the sensory environment are encoded in neural activity. Current auditory models of loudness perception can be used to make detailed predictions about the neural activity of the cortex as an individual listens to speech. We used two such models (loudness-sones and loudness-phons), varying in their psychophysiological realism, to predict the instantaneous loudness contours produced by 480 isolated words. These two set...

  16. 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...

  17. 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...

  18. 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...

  19. Neurochemical correlates of. gamma. -aminobutyrate (GABA) inhibition in cat visual cortex

    Energy Technology Data Exchange (ETDEWEB)

    Balcar, V.J.; Dreher, B. (Univ. of Sydney (Australia))

    1990-01-01

    High affinity binding of ({sup 3}H){gamma}-aminobutyric acid (GABA) to neuronal membranes from different parts of cat visual cortex was tested for sensitivity to GABA{sub A} agonists isoguvacine and THIP, GABA{sub A} antagonist SR95531 and GABA{sub B} agonist baclofen. Some of the GABA{sub A}-binding sites were found to have a very low affinity for THIP, suggesting the presence and, possibly, uneven distribution of non-synaptic GABA{sub A} receptors in cat visual cortex. There were no differences in K{sub m} and V{sub max} values of high affinity uptake of GABA and in the potency of K{sup +}-stimulated release of GABA, between primary and association cortices. Consequently, the present results indicate that despite the anatomical and physiological differences between the primary and association feline visual cortices the neurochemical characteristics of GABAergic inhibition are very similar in the two regions.

  20. Neurochemical correlates of γ-aminobutyrate (GABA) inhibition in cat visual cortex

    International Nuclear Information System (INIS)

    High affinity binding of [3H]γ-aminobutyric acid (GABA) to neuronal membranes from different parts of cat visual cortex was tested for sensitivity to GABAA agonists isoguvacine and THIP, GABAA antagonist SR95531 and GABAB agonist baclofen. Some of the GABAA-binding sites were found to have a very low affinity for THIP, suggesting the presence and, possibly, uneven distribution of non-synaptic GABAA receptors in cat visual cortex. There were no differences in Km and Vmax values of high affinity uptake of GABA and in the potency of K+-stimulated release of GABA, between primary and association cortices. Consequently, the present results indicate that despite the anatomical and physiological differences between the primary and association feline visual cortices the neurochemical characteristics of GABAergic inhibition are very similar in the two regions

  1. 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

  2. Directional tunings independent of orientation in the primary visual cortex of the cat

    Institute of Scientific and Technical Information of China (English)

    陈垚; 李兵; 李宝旺; 刁云程

    2001-01-01

    A family of moving ‘random-line' patterns was developed and used to study the directional tuning of 91 single units in cat primary visual cortex (V1). The results suggest that, in addition to the well-known orientation-dependent mechanism, there is also some kind of orientation-independent mechanism underlying the direction selectivity. The directional tuning of the neurons varies in accordance with the increase of orientation or non-orientation element in the stimulus.

  3. Columnar Architecture Sculpted by GABA Circuits in Developing Cat Visual Cortex

    OpenAIRE

    Hensch, Takao K.; Stryker, Michael P.

    2004-01-01

    The mammalian visual cortex is organized into columns. Here, we examine cortical influences upon developing visual afferents in the cat by altering intrinsic γ-aminobutyric acid (GABA)–mediated inhibition with benzodiazepines. Local enhancement by agonist (diazepam) infusion did not perturb visual responsiveness, but did widen column spacing. An inverse agonist (DMCM) produced the opposite effect. Thus, intracortical inhibitory circuits shape the geometry of incoming thalamic arbors, suggesti...

  4. Visual responses in adult cat visual cortex depend on N-methyl-D-aspartate receptors.

    OpenAIRE

    Miller, K. D.; Chapman, B; Stryker, M.P.

    1989-01-01

    We have investigated the role of the N-methyl-D-aspartate (NMDA) receptor, a subtype of glutamate receptor, in the responses of cells in adult cat visual cortex. After intracortical infusion of the NMDA receptor antagonist DL-2-amino-5-phosphonovalerate (DL-APV) for one day, iontophoretic responses to NMDA, to kainate, and to quisqualate revealed a receptor blockade specific to NMDA receptors and extending several millimeters from the cannula. In this region, neuronal responses to visual stim...

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

    Directory of Open Access Journals (Sweden)

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

    Science.gov (United States)

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

    2013-06-01

    Electrical stimulation of the auditory nerve with a cochlear implant (CI) is the method of choice for treatment of severe-to-profound hearing loss. Understanding how the human auditory cortex responds to CI stimulation is important for advances in stimulation paradigms and rehabilitation strategies. In this study, auditory cortical responses to CI stimulation were recorded intracranially in a neurosurgical patient to examine directly the functional organization of the auditory cortex and compare the findings with those obtained in normal-hearing subjects. The subject was a bilateral CI user with a 20-year history of deafness and refractory epilepsy. As part of the epilepsy treatment, a subdural grid electrode was implanted over the left temporal lobe. Pure tones, click trains, sinusoidal amplitude-modulated noise, and speech were presented via the auxiliary input of the right CI speech processor. Additional experiments were conducted with bilateral CI stimulation. Auditory event-related changes in cortical activity, characterized by the averaged evoked potential and event-related band power, were localized to posterolateral superior temporal gyrus. Responses were stable across recording sessions and were abolished under general anesthesia. Response latency decreased and magnitude increased with increasing stimulus level. More apical intracochlear stimulation yielded the largest responses. Cortical evoked potentials were phase-locked to the temporal modulations of periodic stimuli and speech utterances. Bilateral electrical stimulation resulted in minimal artifact contamination. This study demonstrates the feasibility of intracranial electrophysiological recordings of responses to CI stimulation in a human subject, shows that cortical response properties may be similar to those obtained in normal-hearing individuals, and provides a basis for future comparisons with extracranial recordings. PMID:23519390

  7. Electrocorticographic Activation within Human Auditory Cortex during Dialog-Based Language and Cognitive Testing.

    Science.gov (United States)

    Nourski, Kirill V; Steinschneider, Mitchell; Rhone, Ariane E

    2016-01-01

    Current models of cortical speech and language processing include multiple regions within the temporal lobe of both hemispheres. Human communication, by necessity, involves complex interactions between regions subserving speech and language processing with those involved in more general cognitive functions. To assess these interactions, we utilized an ecologically salient conversation-based approach. This approach mandates that we first clarify activity patterns at the earliest stages of cortical speech processing. Therefore, we examined high gamma (70-150 Hz) responses within the electrocorticogram (ECoG) recorded simultaneously from Heschl's gyrus (HG) and lateral surface of the superior temporal gyrus (STG). Subjects were neurosurgical patients undergoing evaluation for treatment of medically intractable epilepsy. They performed an expanded version of the Mini-mental state examination (MMSE), which included additional spelling, naming, and memory-based tasks. ECoG was recorded from HG and the STG using multicontact depth and subdural electrode arrays, respectively. Differences in high gamma activity during listening to the interviewer and the subject's self-generated verbal responses were quantified for each recording site and across sites within HG and STG. The expanded MMSE produced widespread activation in auditory cortex of both hemispheres. No significant difference was found between activity during listening to the interviewer's questions and the subject's answers in posteromedial HG (auditory core cortex). A different pattern was observed throughout anterolateral HG and posterior and middle portions of lateral STG (non-core auditory cortical areas), where activity was significantly greater during listening compared to speaking. No systematic task-specific differences in the degree of suppression during speaking relative to listening were found in posterior and middle STG. Individual sites could, however, exhibit task-related variability in the degree of

  8. Electrocorticographic Activation within Human Auditory Cortex during Dialog-Based Language and Cognitive Testing

    Science.gov (United States)

    Nourski, Kirill V.; Steinschneider, Mitchell; Rhone, Ariane E.

    2016-01-01

    Current models of cortical speech and language processing include multiple regions within the temporal lobe of both hemispheres. Human communication, by necessity, involves complex interactions between regions subserving speech and language processing with those involved in more general cognitive functions. To assess these interactions, we utilized an ecologically salient conversation-based approach. This approach mandates that we first clarify activity patterns at the earliest stages of cortical speech processing. Therefore, we examined high gamma (70–150 Hz) responses within the electrocorticogram (ECoG) recorded simultaneously from Heschl’s gyrus (HG) and lateral surface of the superior temporal gyrus (STG). Subjects were neurosurgical patients undergoing evaluation for treatment of medically intractable epilepsy. They performed an expanded version of the Mini-mental state examination (MMSE), which included additional spelling, naming, and memory-based tasks. ECoG was recorded from HG and the STG using multicontact depth and subdural electrode arrays, respectively. Differences in high gamma activity during listening to the interviewer and the subject’s self-generated verbal responses were quantified for each recording site and across sites within HG and STG. The expanded MMSE produced widespread activation in auditory cortex of both hemispheres. No significant difference was found between activity during listening to the interviewer’s questions and the subject’s answers in posteromedial HG (auditory core cortex). A different pattern was observed throughout anterolateral HG and posterior and middle portions of lateral STG (non-core auditory cortical areas), where activity was significantly greater during listening compared to speaking. No systematic task-specific differences in the degree of suppression during speaking relative to listening were found in posterior and middle STG. Individual sites could, however, exhibit task-related variability in the

  9. 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.

  10. Wiener-Volterra characterization of neurons in primary auditory cortex using poisson-distributed impulse train inputs.

    Science.gov (United States)

    Pienkowski, Martin; Shaw, Greg; Eggermont, Jos J

    2009-06-01

    An extension of the Wiener-Volterra theory to a Poisson-distributed impulse train input was used to characterize the temporal response properties of neurons in primary auditory cortex (AI) of the ketamine-anesthetized cat. Both first- and second-order "Poisson-Wiener" (PW) models were tested on their predictions of temporal modulation transfer functions (tMTFs), which were derived from extracellular spike responses to periodic click trains with click repetition rates of 2-64 Hz. Second-order (i.e., nonlinear) PW fits to the measured tMTFs could be described as very good in a majority of cases (e.g., predictability >or=80%) and were almost always superior to first-order (i.e., linear) fits. In all sampled neurons, second-order PW kernels showed strong compressive nonlinearities (i.e., a depression of the impulse response) but never expansive nonlinearities (i.e., a facilitation of the impulse response). In neurons with low-pass tMTFs, the depression decayed exponentially with the interstimulus lag, whereas in neurons with band-pass tMTFs, the depression was typically double-peaked, and the second peak occurred at a lag that correlated with the neuron's best modulation frequency. It appears that modulation-tuning in AI arises in part from an interplay of two nonlinear processes with distinct time courses. PMID:19321635

  11. 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

  12. 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.

  13. Auditory-prefrontal axonal connectivity in the macaque cortex: quantitative assessment of processing streams.

    Science.gov (United States)

    Bezgin, Gleb; Rybacki, Konrad; van Opstal, A John; Bakker, Rembrandt; Shen, Kelly; Vakorin, Vasily A; McIntosh, Anthony R; Kötter, Rolf

    2014-08-01

    Primate sensory systems subserve complex neurocomputational functions. Consequently, these systems are organised anatomically in a distributed fashion, commonly linking areas to form specialised processing streams. Each stream is related to a specific function, as evidenced from studies of the visual cortex, which features rather prominent segregation into spatial and non-spatial domains. It has been hypothesised that other sensory systems, including auditory, are organised in a similar way on the cortical level. Recent studies offer rich qualitative evidence for the dual stream hypothesis. Here we provide a new paradigm to quantitatively uncover these patterns in the auditory system, based on an analysis of multiple anatomical studies using multivariate techniques. As a test case, we also apply our assessment techniques to more ubiquitously-explored visual system. Importantly, the introduced framework opens the possibility for these techniques to be applied to other neural systems featuring a dichotomised organisation, such as language or music perception. PMID:24980416

  14. Anatomical pathways for auditory memory II: information from rostral superior temporal gyrus to dorsolateral temporal pole and medial temporal cortex.

    Science.gov (United States)

    Muñoz-López, M; Insausti, R; Mohedano-Moriano, A; Mishkin, M; Saunders, R C

    2015-01-01

    Auditory recognition memory in non-human primates differs from recognition memory in other sensory systems. Monkeys learn the rule for visual and tactile delayed matching-to-sample within a few sessions, and then show one-trial recognition memory lasting 10-20 min. In contrast, monkeys require hundreds of sessions to master the rule for auditory recognition, and then show retention lasting no longer than 30-40 s. Moreover, unlike the severe effects of rhinal lesions on visual memory, such lesions have no effect on the monkeys' auditory memory performance. The anatomical pathways for auditory memory may differ from those in vision. Long-term visual recognition memory requires anatomical connections from the visual association area TE with areas 35 and 36 of the perirhinal cortex (PRC). We examined whether there is a similar anatomical route for auditory processing, or that poor auditory recognition memory may reflect the lack of such a pathway. Our hypothesis is that an auditory pathway for recognition memory originates in the higher order processing areas of the rostral superior temporal gyrus (rSTG), and then connects via the dorsolateral temporal pole to access the rhinal cortex of the medial temporal lobe. To test this, we placed retrograde (3% FB and 2% DY) and anterograde (10% BDA 10,000 mW) tracer injections in rSTG and the dorsolateral area 38 DL of the temporal pole. Results showed that area 38DL receives dense projections from auditory association areas Ts1, TAa, TPO of the rSTG, from the rostral parabelt and, to a lesser extent, from areas Ts2-3 and PGa. In turn, area 38DL projects densely to area 35 of PRC, entorhinal cortex (EC), and to areas TH/TF of the posterior parahippocampal cortex. Significantly, this projection avoids most of area 36r/c of PRC. This anatomical arrangement may contribute to our understanding of the poor auditory memory of rhesus monkeys. PMID:26041980

  15. Population response characteristics of intrinsic signals in the cat somatosensory cortex following canine mechanical stimulation.

    Science.gov (United States)

    Tao, Jianxiang; Wang, Jian; Li, Zhong; Meng, Jianjun; Yu, Hongbo

    2016-08-01

    Intrinsic signal optical imaging has been widely used to measure functional maps in various sensory cortices due to better spatial resolution and sensitivity for detecting cortical neuroplasticity. However, application of this technique in dentistry has not been reported. In this study, intrinsic signal optical imaging was used to investigate mechanically driven responses in the cat somatosensory cortex, when punctate mechanical stimuli were applied to maxillary canines. The global signal and its spatial organization pattern were obtained. Global signal strength gradually increased with stimulus strength. There was no significant difference in response strength between contralateral and ipsilateral mechanical stimulation. A slightly greater response was recorded in the sigmoidal gyrus than in the coronal gyrus. The cat somatosensory cortex activated by sensory inputs from mechanical stimulation of canines lacks both topographical and functional organization. It is not organized into columns that represent sensory input from each tooth or direction of stimulation. These results demonstrate that intrinsic signal optical imaging is a valid tool for investigating neural responses and neuroplasticity in the somatosensory cortex that represents teeth. PMID:27163378

  16. Functional Imaging of Human Vestibular Cortex Activity Elicited by Skull Tap and Auditory Tone Burst

    Science.gov (United States)

    Noohi, F.; Kinnaird, C.; Wood, S.; Bloomberg, J.; Mulavara, A.; Seidler, R.

    2016-01-01

    The current study characterizes brain activation in response to two modes of vestibular stimulation: skull tap and auditory tone burst. The auditory tone burst has been used in previous studies to elicit either the vestibulo-spinal reflex (saccular-mediated colic Vestibular Evoked Myogenic Potentials (cVEMP)), or the ocular muscle response (utricle-mediated ocular VEMP (oVEMP)). Some researchers have reported that air-conducted skull tap elicits both saccular and utricle-mediated VEMPs, while being faster and less irritating for the subjects. However, it is not clear whether the skull tap and auditory tone burst elicit the same pattern of cortical activity. Both forms of stimulation target the otolith response, which provides a measurement of vestibular function independent from semicircular canals. This is of high importance for studying otolith-specific deficits, including gait and balance problems that astronauts experience upon returning to earth. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation. Here we hypothesized that skull taps elicit similar patterns of cortical activity as the auditory tone bursts, and previous vestibular imaging studies. Subjects wore bilateral MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in the supine position, with eyes closed. Subjects received both forms of the stimulation in a counterbalanced fashion. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular system, resulting in the vestibular cortical response. Auditory tone bursts were also delivered for comparison. To validate our stimulation method, we measured the ocular VEMP outside of the scanner. This measurement showed that both skull tap and auditory

  17. 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

  18. 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.

  19. 听觉皮层信号处理%Information processing in auditory cortex

    Institute of Scientific and Technical Information of China (English)

    王晓勤

    2009-01-01

    In contrast to the visual system, the auditory system has longer subcortical pathways and more spiking synapses between the peripheral receptors and the cortex. This unique organization reflects the needs of the auditory system to extract behaviorally relevant information from a complex acoustic environment using strategies different from those used by other sensory systems. The neural representations of acoustic information in auditory cortex include two types of important transformations: the non-isomorphic transformation of acoustic features and the transformation from acoustical to perceptual dimensions. Neural representations in auditory cortex are also modulated by auditory feedback and vocal control signals during speaking or vocalization. The challenges facing auditory neuroscientists and biomedical engineers are to understand neural coding mechanisms in the brain underlying such transformations. I will use recent findings from my laboratory to illustrate how acoustic information is processed in the primate auditory cortex and discuss its implications for neural processing of speech and music in the brain as well as for the design of neural prosthetic devices such as cochlear implants. We have used a combination of neurophysiological techniques and quantitative engineering tools to investigate these problems.%听觉系统和视觉系统的不同之处在于:听觉系统在外周感受器和听皮层间具有更长的皮层下通路和更多的突触联系.该特殊结构反应了听觉系统从复杂听觉环境中提取与行为相关信号的机制与其他感觉系统不同.听皮层神经信号处理包括两种重要的转换机制,声音信号的非同构转换以及从声音感受到知觉层面的转换.听觉皮层神经编码机制同时也受到听觉反馈和语言或发声过程中发声信号的调控.听觉神经科学家和生物医学工程师所面临的挑战便是如何去理解大脑中这些转换的编码机制.我将会用我实验

  20. Perinatal exposure to a noncoplanar polychlorinated biphenyl alters tonotopy, receptive fields, and plasticity in rat primary auditory cortex

    OpenAIRE

    Kenet, T; Froemke, R. C.; Schreiner, C. E.; Pessah, I N; Merzenich, M. M.

    2007-01-01

    Noncoplanar polychlorinated biphenyls (PCBs) are widely dispersed in human environment and tissues. Here, an exemplar noncoplanar PCB was fed to rat dams during gestation and throughout three subsequent nursing weeks. Although the hearing sensitivity and brainstem auditory responses of pups were normal, exposure resulted in the abnormal development of the primary auditory cortex (A1). A1 was irregularly shaped and marked by internal nonresponsive zones, its topographic organization was grossl...

  1. Numbers of specific types of neuron in layer IVab of cat striate cortex.

    OpenAIRE

    Solnick, B; Davis, T L; Sterling, P

    1984-01-01

    Layer IVab of the visual cortex (area 17) of the cat contains about 51,400 neurons per mm3, including about 400-1200 per mm3 of each of three categories of neuron believed from previous work to represent discrete types. Each type forms about 0.5-1.5% of all the IVab neurons, which suggests that the total number of types in this layer might be much greater than previously supposed, perhaps as many as 50 or more. From their densities and estimates of their dendritic fields, we calculate that ea...

  2. Neuronal activity in primate prefrontal cortex related to goal-directed behavior during auditory working memory tasks.

    Science.gov (United States)

    Huang, Ying; Brosch, Michael

    2016-06-01

    Prefrontal cortex (PFC) has been documented to play critical roles in goal-directed behaviors, like representing goal-relevant events and working memory (WM). However, neurophysiological evidence for such roles of PFC has been obtained mainly with visual tasks but rarely with auditory tasks. In the present study, we tested roles of PFC in auditory goal-directed behaviors by recording local field potentials in the auditory region of left ventrolateral PFC while a monkey performed auditory WM tasks. The tasks consisted of multiple events and required the monkey to change its mental states to achieve the reward. The events were auditory and visual stimuli, as well as specific actions. Mental states were engaging in the tasks and holding task-relevant information in auditory WM. We found that, although based on recordings from one hemisphere in one monkey only, PFC represented multiple events that were important for achieving reward, including auditory and visual stimuli like turning on and off an LED, as well as bar touch. The responses to auditory events depended on the tasks and on the context of the tasks. This provides support for the idea that neuronal representations in PFC are flexible and can be related to the behavioral meaning of stimuli. We also found that engaging in the tasks and holding information in auditory WM were associated with persistent changes of slow potentials, both of which are essential for auditory goal-directed behaviors. Our study, on a single hemisphere in a single monkey, reveals roles of PFC in auditory goal-directed behaviors similar to those in visual goal-directed behaviors, suggesting that functions of PFC in goal-directed behaviors are probably common across the auditory and visual modality. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26874071

  3. Multitarget surgical neuromodulation: Combined C2 and auditory cortex implantation for tinnitus.

    Science.gov (United States)

    De Ridder, Dirk; Vanneste, Sven

    2015-03-30

    Tinnitus, as a phantom sound can express itself as a pure tone and as a noise-like sound. It is notoriously difficult to treat, and in medically, psychologically and audiologically intractable tinnitus patients sometimes intracranial electrodes overlying the auditory cortex are implanted. In this case report, we describe a patient who had a complete resolution of the pure tone component of his tinnitus by an auditory cortex implant, without any beneficial effect on the noise-like aspect of his tinnitus, even after changing the stimulation design to burst stimulation, which is known to treat noise-like tinnitus better than tonic stimulation. After an initial successful treatment of his noise-like component with transcutaneus electrical nerve stimulation, a wire electrode is inserted subcutaneously and connected to his internal pulse generator. With the dual stimulation his pure tone tinnitus remains abolished after 5 years of stimulation and his noise-like tinnitus is improved by 50%, from 8/10 to 4/10. This case report suggests that multi-target stimulation might be better than single target implantation in selected cases. PMID:25703225

  4. Source analysis of magnetic field responses from the human auditory cortex elicited by short speech sounds.

    Science.gov (United States)

    Kuriki, S; Okita, Y; Hirata, Y

    1995-01-01

    We made a detailed source analysis of the magnetic field responses that were elicited in the human brain by different monosyllabic speech sounds, including vowel, plosive, fricative, and nasal speech. Recordings of the magnetic field responses from a lateral area of the left hemisphere of human subjects were made using a multichannel SQUID magnetometer, having 37 field-sensing coils. A single source of the equivalent current dipole of the field was estimated from the spatial distribution of the evoked responses. The estimated sources of an N1m wave occurring at about 100 ms after the stimulus onset of different monosyllables were located close to each other within a 10-mm-sided cube in the three-dimensional space of the brain. Those sources registered on the magnetic resonance images indicated a restricted area in the auditory cortex, including Heschl's gyri in the superior temporal plane. In the spatiotemporal domain the sources exhibited apparent movements, among which anterior shift with latency increase on the anteroposterior axis and inferior shift on the inferosuperior axis were common in the responses to all monosyllables. However, selective movements that depended on the type of consonants were observed on the mediolateral axis; the sources of plosive and fricative responses shifted laterally with latency increase, but the source of the vowel response shifted medially. These spatiotemporal movements of the sources are discussed in terms of dynamic excitation of the cortical neurons in multiple areas of the human auditory cortex. PMID:7621933

  5. Distinct Subthreshold Mechanisms Underlying Rate-Coding Principles in Primate Auditory Cortex.

    Science.gov (United States)

    Gao, Lixia; Kostlan, Kevin; Wang, Yunyan; Wang, Xiaoqin

    2016-08-17

    A key computational principle for encoding time-varying signals in auditory and somatosensory cortices of monkeys is the opponent model of rate coding by two distinct populations of neurons. However, the subthreshold mechanisms that give rise to this computation have not been revealed. Because the rate-coding neurons are only observed in awake conditions, it is especially challenging to probe their underlying cellular mechanisms. Using a novel intracellular recording technique that we developed in awake marmosets, we found that the two types of rate-coding neurons in auditory cortex exhibited distinct subthreshold responses. While the positive-monotonic neurons (monotonically increasing firing rate with increasing stimulus repetition frequency) displayed sustained depolarization at high repetition frequency, the negative-monotonic neurons (opposite trend) instead exhibited hyperpolarization at high repetition frequency but sustained depolarization at low repetition frequency. The combination of excitatory and inhibitory subthreshold events allows the cortex to represent time-varying signals through these two opponent neuronal populations. PMID:27478016

  6. Auditory Cortex tACS and tRNS for Tinnitus: Single versus Multiple Sessions

    Directory of Open Access Journals (Sweden)

    Laura Claes

    2014-01-01

    Full Text Available Tinnitus is the perception of a sound in the absence of an external acoustic source, which often exerts a significant impact on the quality of life. Currently there is evidence that neuroplastic changes in both neural pathways are involved in the generation and maintaining of tinnitus. Neuromodulation has been suggested to interfere with these neuroplastic alterations. In this study we aimed to compare the effect of two upcoming forms of transcranial electrical neuromodulation: alternating current stimulation (tACS and random noise stimulation (tRNS, both applied on the auditory cortex. A database with 228 patients with chronic tinnitus who underwent noninvasive neuromodulation was retrospectively analyzed. The results of this study show that a single session of tRNS induces a significant suppressive effect on tinnitus loudness and distress, in contrast to tACS. Multiple sessions of tRNS augment the suppressive effect on tinnitus loudness but have no effect on tinnitus distress. In conclusion this preliminary study shows a possibly beneficial effect of tRNS on tinnitus and can be a motivation for future randomized placebo-controlled clinical studies with auditory tRNS for tinnitus. Auditory alpha-modulated tACS does not seem to be contributing to the treatment of tinnitus.

  7. Decoding four different sound-categories in the auditory cortex using functional near-infrared spectroscopy.

    Science.gov (United States)

    Hong, Keum-Shik; Santosa, Hendrik

    2016-03-01

    The ability of the auditory cortex in the brain to distinguish different sounds is important in daily life. This study investigated whether activations in the auditory cortex caused by different sounds can be distinguished using functional near-infrared spectroscopy (fNIRS). The hemodynamic responses (HRs) in both hemispheres using fNIRS were measured in 18 subjects while exposing them to four sound categories (English-speech, non-English-speech, annoying sounds, and nature sounds). As features for classifying the different signals, the mean, slope, and skewness of the oxy-hemoglobin (HbO) signal were used. With regard to the language-related stimuli, the HRs evoked by understandable speech (English) were observed in a broader brain region than were those evoked by non-English speech. Also, the magnitudes of the HbO signals evoked by English-speech were higher than those of non-English speech. The ratio of the peak values of non-English and English speech was 72.5%. Also, the brain region evoked by annoying sounds was wider than that by nature sounds. However, the signal strength for nature sounds was stronger than that for annoying sounds. Finally, for brain-computer interface (BCI) purposes, the linear discriminant analysis (LDA) and support vector machine (SVM) classifiers were applied to the four sound categories. The overall classification performance for the left hemisphere was higher than that for the right hemisphere. Therefore, for decoding of auditory commands, the left hemisphere is recommended. Also, in two-class classification, the annoying vs. nature sounds comparison provides a higher classification accuracy than the English vs. non-English speech comparison. Finally, LDA performs better than SVM. PMID:26828741

  8. Mirrored patterns of lateralized neuronal activation reflect old and new memories in the avian auditory cortex.

    Science.gov (United States)

    Olson, Elizabeth M; Maeda, Rie K; Gobes, Sharon M H

    2016-08-25

    In monolingual humans, language-related brain activation shows a distinct lateralized pattern, in which the left hemisphere is often dominant. Studies are not as conclusive regarding the localization of the underlying neural substrate for language in sequential language learners. Lateralization of the neural substrate for first and second language depends on a number of factors including proficiency and early experience with each language. Similar to humans learning speech, songbirds learn their vocalizations from a conspecific tutor early in development. Here, we show mirrored patterns of lateralization in the avian analog of the mammalian auditory cortex (the caudomedial nidopallium [NCM]) in sequentially tutored zebra finches (Taeniopygia guttata​) in response to their first tutor song, learned early in development, and their second tutor song, learned later in development. The greater the retention of song from their first tutor, the more right-dominant the birds were when exposed to that song; the more birds learned from their second tutor, the more left-dominant they were when exposed to that song. Thus, the avian auditory cortex may preserve lateralized neuronal traces of old and new tutor song memories, which are dependent on proficiency of song learning. There is striking resemblance in humans: early-formed language representations are maintained in the brain even if exposure to that language is discontinued. The switching of hemispheric dominance related to the acquisition of early auditory memories and subsequent encoding of more recent memories may be an evolutionary adaptation in vocal learners necessary for the behavioral flexibility to acquire novel vocalizations, such as a second language. PMID:27288718

  9. Functional segregation of monaural and binaural selectivity in the pallid bat auditory cortex.

    Science.gov (United States)

    Razak, Khaleel A

    2016-07-01

    Different fields of the auditory cortex can be distinguished by the extent and level tolerance of spatial selectivity. The mechanisms underlying the range of spatial tuning properties observed across cortical fields are unclear. Here, this issue was addressed in the pallid bat because its auditory cortex contains two segregated regions of response selectivity that serve two different behaviors: echolocation for obstacle avoidance and localization of prey-generated noise. This provides the unique opportunity to examine mechanisms of spatial properties in two functionally distinct regions. Previous studies have shown that spatial selectivity of neurons in the region selective for noise (noise-selective region, NSR) is level tolerant and shaped by interaural level difference (ILD) selectivity. In contrast, spatial selectivity of neurons in the echolocation region ('FM sweep-selective region' or FMSR) is strongly level dependent with many neurons responding to multiple distinct spatial locations for louder sounds. To determine the mechanisms underlying such level dependence, frequency, azimuth, rate-level responses and ILD selectivity were measured from the same FMSR neurons. The majority (∼75%) of FMSR neurons were monaural (ILD insensitive). Azimuth tuning curves expanded or split into multiple peaks with increasing sound level in a manner that was predicted by the rate-level response of neurons. These data suggest that azimuth selectivity of FMSR neurons depends more on monaural ear directionality and rate-level responses. The pallid bat cortex utilizes segregated monaural and binaural regions to process echoes and prey-generated noise. Together the pallid bat FMSR/NSR data provide mechanistic explanations for a broad range of spatial tuning properties seen across species. PMID:27233917

  10. Developmental Trajectories of Auditory Cortex Synaptic Structures and Gap-Prepulse Inhibition of Acoustic Startle Between Early Adolescence and Young Adulthood in Mice.

    Science.gov (United States)

    Moyer, Caitlin E; Erickson, Susan L; Fish, Kenneth N; Thiels, Edda; Penzes, Peter; Sweet, Robert A

    2016-05-01

    Cortical excitatory and inhibitory synapses are disrupted in schizophrenia, the symptoms of which often emerge during adolescence, when cortical excitatory synapses undergo pruning. In auditory cortex, a brain region implicated in schizophrenia, little is known about the development of excitatory and inhibitory synapses between early adolescence and young adulthood, and how these changes impact auditory cortex function. We used immunohistochemistry and quantitative fluorescence microscopy to quantify dendritic spines and GAD65-expressing inhibitory boutons in auditory cortex of early adolescent, late adolescent, and young adult mice. Numbers of spines decreased between early adolescence and young adulthood, during which time responses increased in an auditory cortex-dependent sensory task, silent gap-prepulse inhibition of the acoustic startle reflex (gap-PPI). Within-bouton GAD65 protein and GAD65-expressing bouton numbers decreased between late adolescence and young adulthood, a delay in onset relative to spine and gap-PPI changes. In mice lacking the spine protein kalirin, there were no significant changes in spine number, within-bouton GAD65 protein, or gap-PPI between adolescence and young adulthood. These results illustrate developmental changes in auditory cortex spines, inhibitory boutons, and auditory cortex function between adolescence and young adulthood, and provide insights into how disrupted adolescent neurodevelopment could contribute to auditory cortex synapse pathology and auditory impairments. PMID:25759333

  11. On the Nature of the Intrinsic Connectivity of the Cat Motor Cortex: Evidence for a Recurrent Neural Network Topology

    DEFF Research Database (Denmark)

    Capaday, Charles; Ethier, C; Brizzi, L;

    2009-01-01

    Capaday C, Ethier C, Brizzi L, Sik A, van Vreeswijk C, Gingras D. On the nature of the intrinsic connectivity of the cat motor cortex: evidence for a recurrent neural network topology. J Neurophysiol 102: 2131-2141, 2009. First published July 22, 2009; doi: 10.1152/jn.91319.2008. The details...... and functional significance of the intrinsic horizontal connections between neurons in the motor cortex (MCx) remain to be clarified. To further elucidate the nature of this intracortical connectivity pattern, experiments were done on the MCx of three cats. The anterograde tracer biocytin was ejected...

  12. TNF-A Levels throughout the Critical Period for Experience-Dependent Plasticity in the Rat Primary Auditory Cortex

    NARCIS (Netherlands)

    Man, WH; Madeira, Caroline; Zhou, Xiaoming; Merzenich, Michael M; Panizzutti, Rogerio

    2015-01-01

    Tumor necrosis factor- alpha (TNF-α) is likely to play a role in brain plasticity. To determine whether TNF-α levels change throughout a critical period of experience-dependent brain plasticity, we assessed these levels in the primary auditory cortex of rats before, during and after the critical per

  13. The effect of electrical stimulation of the auditory cortex on neuronal activity in the medial geniculate body of the rat

    Czech Academy of Sciences Publication Activity Database

    Moucha, R.; Popelář, Jiří; Šuta, Daniel; Kilgard, P.; Syka, Josef

    Prague : organizátor symposia, 2005. s. 109. [Conference of the Czech Neuroscience Society /5./, The Annual Meeting of the Network of European Neuroscience Institutes. 19.11.2005-21.11.2005, Prague] R&D Projects: GA ČR GA309/04/1074 Institutional research plan: CEZ:AV0Z50390512 Keywords : auditory cortex Subject RIV: FH - Neurology

  14. Physiological activation of the human cerebral cortex during auditory perception and speech revealed by regional increases in cerebral blood flow

    DEFF Research Database (Denmark)

    Lassen, N A; Friberg, L

    1988-01-01

    methods, that are based of the use of radioactive tracers, can be applied in the same manner for mapping cortex activity. In particular single photon tomography SPECT is readily applicable to clinical audiology, so that the cortical components of the auditory processing can be more closely investigated....

  15. Effects of stimulation parameters and electrode location on thresholds for epidural stimulation of cat motor cortex

    Science.gov (United States)

    Wongsarnpigoon, Amorn; Grill, Warren M.

    2011-12-01

    Epidural electrical stimulation (ECS) of the motor cortex is a developing therapy for neurological disorders. Both placement and programming of ECS systems may affect the therapeutic outcome, but the treatment parameters that will maximize therapeutic outcomes and minimize side effects are not known. We delivered ECS to the motor cortex of anesthetized cats and investigated the effects of electrode placement and stimulation parameters on thresholds for evoking motor responses in the contralateral forelimb. Thresholds were inversely related to stimulation frequency and the number of pulses per stimulus train. Thresholds were lower over the forelimb representation in motor cortex (primary site) than surrounding sites (secondary sites), and thresholds at sites 4 mm away. Electrode location and montage influenced the effects of polarity on thresholds: monopolar anodic and cathodic thresholds were not significantly different over the primary site, cathodic thresholds were significantly lower than anodic thresholds over secondary sites and bipolar thresholds were significantly lower with the anode over the primary site than with the cathode over the primary site. A majority of bipolar thresholds were either between or equal to the respective monopolar thresholds, but several bipolar thresholds were greater than or less than the monopolar thresholds of both the anode and cathode. During bipolar stimulation, thresholds were influenced by both electric field superposition and indirect, synaptically mediated interactions. These results demonstrate the influence of stimulation parameters and electrode location during cortical stimulation, and these effects should be considered during the programming of systems for therapeutic cortical stimulation.

  16. Avalanche Analysis from Multielectrode Ensemble Recordings in Cat, Monkey, and Human Cerebral Cortex during Wakefulness and Sleep

    OpenAIRE

    Nima eDehghani; Hatsopoulos, Nicholas G.; Haga, Zach D.; Rebecca eParker; Bradley eGreger; Eric eHalgren; Sydney S Cash; Alain eDestexhe

    2012-01-01

    Self-organized critical states are found in many natural systems, from earthquakes to forest fires, they have also been observed in neural systems, particularly, in neuronal cultures. However, the presence of critical states in the awake brain remains controversial. Here, we compared avalanche analyses performed on different in vivo preparations during wakefulness, slow-wave sleep, and REM sleep, using high density electrode arrays in cat motor cortex (96 electrodes), monkey motor cortex and ...

  17. Representations of specific acoustic patterns in the auditory cortex and hippocampus.

    Science.gov (United States)

    Kumar, Sukhbinder; Bonnici, Heidi M; Teki, Sundeep; Agus, Trevor R; Pressnitzer, Daniel; Maguire, Eleanor A; Griffiths, Timothy D

    2014-09-22

    Previous behavioural studies have shown that repeated presentation of a randomly chosen acoustic pattern leads to the unsupervised learning of some of its specific acoustic features. The objective of our study was to determine the neural substrate for the representation of freshly learnt acoustic patterns. Subjects first performed a behavioural task that resulted in the incidental learning of three different noise-like acoustic patterns. During subsequent high-resolution functional magnetic resonance imaging scanning, subjects were then exposed again to these three learnt patterns and to others that had not been learned. Multi-voxel pattern analysis was used to test if the learnt acoustic patterns could be 'decoded' from the patterns of activity in the auditory cortex and medial temporal lobe. We found that activity in planum temporale and the hippocampus reliably distinguished between the learnt acoustic patterns. Our results demonstrate that these structures are involved in the neural representation of specific acoustic patterns after they have been learnt. PMID:25100695

  18. Stimulus-invariant processing and spectrotemporal reverse correlation in primary auditory cortex.

    Science.gov (United States)

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

    2006-04-01

    The spectrotemporal receptive field (STRF) provides a versatile and integrated, spectral and temporal, functional characterization of single cells in primary auditory cortex (AI). In this paper, we explore the origin of, and relationship between, different ways of measuring and analyzing an STRF. We demonstrate that STRFs measured using a spectrotemporally diverse array of broadband stimuli-such as dynamic ripples, spectrotemporally white noise, and temporally orthogonal ripple combinations (TORCs)-are very similar, confirming earlier findings that the STRF is a robust linear descriptor of the cell. We also present a new deterministic analysis framework that employs the Fourier series to describe the spectrotemporal modulations contained in the stimuli and responses. Additional insights into the STRF measurements, including the nature and interpretation of measurement errors, is presented using the Fourier transform, coupled to singular-value decomposition (SVD), and variability analyses including bootstrap. The results promote the utility of the STRF as a core functional descriptor of neurons in AI. PMID:16518572

  19. Auditory sequence processing reveals evolutionarily conserved regions of frontal cortex in macaques and humans.

    Science.gov (United States)

    Wilson, Benjamin; Kikuchi, Yukiko; Sun, Li; Hunter, David; Dick, Frederic; Smith, Kenny; Thiele, Alexander; Griffiths, Timothy D; Marslen-Wilson, William D; Petkov, Christopher I

    2015-01-01

    An evolutionary account of human language as a neurobiological system must distinguish between human-unique neurocognitive processes supporting language and evolutionarily conserved, domain-general processes that can be traced back to our primate ancestors. Neuroimaging studies across species may determine whether candidate neural processes are supported by homologous, functionally conserved brain areas or by different neurobiological substrates. Here we use functional magnetic resonance imaging in Rhesus macaques and humans to examine the brain regions involved in processing the ordering relationships between auditory nonsense words in rule-based sequences. We find that key regions in the human ventral frontal and opercular cortex have functional counterparts in the monkey brain. These regions are also known to be associated with initial stages of human syntactic processing. This study raises the possibility that certain ventral frontal neural systems, which play a significant role in language function in modern humans, originally evolved to support domain-general abilities involved in sequence processing. PMID:26573340

  20. Processing of harmonics in the lateral belt of macaque auditory cortex.

    Science.gov (United States)

    Kikuchi, Yukiko; Horwitz, Barry; Mishkin, Mortimer; Rauschecker, Josef P

    2014-01-01

    Many speech sounds and animal vocalizations contain components, referred to as complex tones, that consist of a fundamental frequency (F0) and higher harmonics. In this study we examined single-unit activity recorded in the core (A1) and lateral belt (LB) areas of auditory cortex in two rhesus monkeys as they listened to pure tones and pitch-shifted conspecific vocalizations ("coos"). The latter consisted of complex-tone segments in which F0 was matched to a corresponding pure-tone stimulus. In both animals, neuronal latencies to pure-tone stimuli at the best frequency (BF) were ~10 to 15 ms longer in LB than in A1. This might be expected, since LB is considered to be at a hierarchically higher level than A1. On the other hand, the latency of LB responses to coos was ~10 to 20 ms shorter than to the corresponding pure-tone BF, suggesting facilitation in LB by the harmonics. This latency reduction by coos was not observed in A1, resulting in similar coo latencies in A1 and LB. Multi-peaked neurons were present in both A1 and LB; however, harmonically-related peaks were observed in LB for both early and late response components, whereas in A1 they were observed only for late components. Our results suggest that harmonic features, such as relationships between specific frequency intervals of communication calls, are processed at relatively early stages of the auditory cortical pathway, but preferentially in LB. PMID:25100935

  1. IMPAIRED PROCESSING IN THE PRIMARY AUDITORY CORTEX OF AN ANIMAL MODEL OF AUTISM

    Directory of Open Access Journals (Sweden)

    Renata eAnomal

    2015-11-01

    Full Text Available Autism is a neurodevelopmental disorder clinically characterized by deficits in communication, lack of social interaction and, repetitive behaviors with restricted interests. A number of studies have reported that sensory perception abnormalities are common in autistic individuals and might contribute to the complex behavioral symptoms of the disorder. In this context, hearing incongruence is particularly prevalent. Considering that some of this abnormal processing might stem from the unbalance of inhibitory and excitatory drives in brain circuitries, we used an animal model of autism induced by valproic acid (VPA during pregnancy in order to investigate the tonotopic organization of the primary auditory cortex (AI and its local inhibitory circuitry. Our results show that VPA rats have distorted primary auditory maps with over-representation of high frequencies, broadly tuned receptive fields and higher sound intensity thresholds as compared to controls. However, we did not detect differences in the number of parvalbumin-positive interneurons in AI of VPA and control rats. Altogether our findings show that neurophysiological impairments of hearing perception in this autism model occur independently of alterations in the number of parvalbumin-expressing interneurons. These data support the notion that fine circuit alterations, rather than gross cellular modification, could lead to neurophysiological changes in the autistic brain.

  2. Neural mechanism of activity spread in the cat motor cortex and its relation to the intrinsic connectivity

    DEFF Research Database (Denmark)

    Capaday, Charles; van Vreeswijk, Carl; Ethier, Christian;

    2011-01-01

    to be determined. To address these issues, an 8 x 8 microelectrode array was inserted in the forelimb area of the cat motor cortex (MCx). The centre of the array had a laser etched hole ∼500 {#956}m in diameter. A microiontophoretic pipette, with a tip diameter of 2–3 {#956}m, containing bicuculline methiodide...

  3. 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

  4. Asymmetries in the representation of space in the human auditory cortex depend on the global stimulus context.

    Science.gov (United States)

    Briley, Paul M; Goman, Adele M; Summerfield, A Quentin

    2016-03-01

    Studies on humans and other mammals have provided evidence for a two-channel or three-channel representation of horizontal space in the auditory system, with one channel maximally responsive to each of the left hemispace, the right hemispace and, possibly, the midline. Mammalian studies have suggested that the contralateral channel is larger in both cortices, but human studies have found this contralateral preference in only one of the cortices. However, human studies are in conflict as to whether the contralateral preference is in the left or the right auditory cortex, and there are a number of methodological differences that this conflict could be attributed to. A key difference between studies is the duration of the silent interval preceding each stimulus and any perception of sound-source movement that the absence of a silent interval creates. We presented auditory noises that alternated between -90° (left) and +90° (right) and recorded neural responses (event-related potentials) using electroencephalography. We randomly varied the duration of the silent interval preceding each stimulus to create a condition with an immediate (local) stimulus context similar to that used in a study reporting contralateral preference in the left auditory cortex, a condition with a local context similar to that in a study reporting contralateral preference in the right auditory cortex, and an intermediate condition. Surprisingly, we found that both auditory cortices exhibited a similarly strong contralateral preference under all conditions, with responses 27% greater, on average, to the contralateral than the ipsilateral space. This suggests that both the cortices can exhibit a contralateral preference, but whether these preferences manifest depends on the global, rather than the local, stimulus context. PMID:26730514

  5. Effect of Contrast on Visual Spatial Summation in Different Cell Categories in Cat Primary Visual Cortex.

    Directory of Open Access Journals (Sweden)

    Ke Chen

    Full Text Available Multiple cell classes have been found in the primary visual cortex, but the relationship between cell types and spatial summation has seldom been studied. Parvalbumin-expressing inhibitory interneurons can be distinguished from pyramidal neurons based on their briefer action potential durations. In this study, we classified V1 cells into fast-spiking units (FSUs and regular-spiking units (RSUs and then examined spatial summation at high and low contrast. Our results revealed that the excitatory classical receptive field and the suppressive non-classical receptive field expanded at low contrast for both FSUs and RSUs, but the expansion was more marked for the RSUs than for the FSUs. For most V1 neurons, surround suppression varied as the contrast changed from high to low. However, FSUs exhibited no significant difference in the strength of suppression between high and low contrast, although the overall suppression decreased significantly at low contrast for the RSUs. Our results suggest that the modulation of spatial summation by stimulus contrast differs across populations of neurons in the cat primary visual cortex.

  6. Processing of harmonics in the lateral belt of macaque auditory cortex

    Directory of Open Access Journals (Sweden)

    YukikoKikuchi

    2014-07-01

    Full Text Available Many speech sounds and animal vocalizations contain components, referred to as complex tones, that consist of a fundamental frequency (F0 and higher harmonics. In this study we examined single-unit activity recorded in the core (A1 and lateral belt (LB areas of auditory cortex in two rhesus monkeys as they listened to pure tones and pitch-shifted conspecific vocalizations (‘coos’. The latter consisted of complex-tone segments in which F0 was matched to a corresponding pure-tone stimulus. In both animals, neuronal latencies to pure-tone stimuli at the best frequency (BF were ~10 to 15 ms longer in LB than in A1. This might be expected, since LB is considered to be at a hierarchically higher level than A1. On the other hand, the latency of LB responses to coos was ~10 to 20 ms shorter than to the corresponding pure-tone BF, suggesting facilitation in LB by the harmonics. This latency reduction by coos was not observed in A1, resulting in similar coo latencies in A1 and LB. Multi-peaked neurons were present in both A1 and LB; however, harmonically-related peaks were observed in LB for both early and late response components, whereas in A1 they were observed only for late components. Our results suggest that harmonic features, such as relationships between specific frequency intervals of communication calls, are processed at relatively early stages of the auditory cortical pathway, but preferentially in LB.

  7. Activity-dependent structural plasticity after aversive experiences in amygdala and auditory cortex pyramidal neurons.

    Science.gov (United States)

    Gruene, Tina; Flick, Katelyn; Rendall, Sam; Cho, Jin Hyung; Gray, Jesse; Shansky, Rebecca

    2016-07-22

    The brain is highly plastic and undergoes changes in response to many experiences. Learning especially can induce structural remodeling of dendritic spines, which is thought to relate to memory formation. Classical Pavlovian fear conditioning (FC) traditionally pairs an auditory cue with an aversive footshock, and has been widely used to study neural processes underlying associative learning and memory. Past research has found dendritic spine changes after FC in several structures. But, due to heterogeneity of cells within brain structures and limitations of traditional neuroanatomical techniques, it is unclear if all cells included in analyses were actually active during learning processes, even if known circuits are isolated. In this study, we employed a novel approach to analyze structural plasticity explicitly in neurons activated by exposure to either cued or uncued footshocks. We used male and female Arc-dVenus transgenic mice, which express the Venus fluorophore driven by the activity-related Arc promoter, to identify neurons that were active during either scenario. We then targeted fluorescent microinjections to Arc+ and neighboring Arc- neurons in the basolateral area of the amygdala (BLA) and auditory association cortex (TeA). In both BLA and TeA, Arc+ neurons had reduced thin and mushroom spine densities compared to Arc- neurons. This effect was present in males and females alike and also in both cued and uncued shock groups. Overall, this study adds to our understanding of how neuronal activity affects structural plasticity, and represents a methodological advance in the ways we can directly relate structural changes to experience-related neural activity. PMID:27155146

  8. Characterizing spatial tuning functions of neurons in the auditory cortex of young and aged monkeys: A new perspective on old data.

    OpenAIRE

    James Engle; Gregg H Recanzone

    2013-01-01

    Age-related hearing deficits are a leading cause of disability among the aged. While some forms of hearing deficits are peripheral in origin, others are centrally mediated. One such deficit is the ability to localize sounds, a critical component for segregating different acoustic objects and events, which is dependent on the auditory cortex. Recent evidence indicates that in aged animals the normal sharpening of spatial tuning between neurons in primary auditory cortex to the caudal latera...

  9. Methylmercury intoxication and histochemical demonstration of NADPH-diaphorase activity in the striate cortex of adult cats

    OpenAIRE

    OLIVEIRA, R. B.; W. Gomes-Leal; J.L.M. do-Nascimento; C.W. Picanço-Diniz

    1998-01-01

    The effects of methylmercury (MeHg) on histochemical demonstration of the NADPH-diaphorase (NADPH-d) activity in the striate cortex were studied in 4 adult cats. Two animals were used as control. The contaminated animals received 50 ml milk containing 0.42 µg MeHg and 100 g fish containing 0.03 µg MeHg daily for 2 months. The level of MeHg in area 17 of intoxicated animals was 3.2 µg/g wet weight brain tissue. Two cats were perfused 24 h after the last dose (group 1) and the other animals wer...

  10. Is humanlike cytoarchitectural asymmetry present in another species with complex social vocalization? A stereologic analysis of mustached bat auditory cortex.

    Science.gov (United States)

    Sherwood, Chet C; Raghanti, Mary Ann; Wenstrup, Jeffrey J

    2005-05-31

    Considerable evidence suggests that left hemispheric lateralization for language comprehension in humans is associated with cortical microstructural asymmetries. However, despite the fact that left hemispheric dominance for the analysis of species-specific social vocalizations has been reported in several other species, little is known concerning microstructural asymmetries in auditory cortex of nonhumans. To test whether such neuroanatomical lateralization characterizes another species with complex social vocalizations, we performed stereologic analyses of Nissl-stained cells in layer III of area DSCF in mustached bats (Pteronotus parnellii). Area DSCF was selected because it contains neurons which are sensitive to several temporal features of conspecific vocalizations. Primary visual cortex (V1) was also studied as a comparative reference. We measured neuron densities, glial densities, and neuronal volumes in both hemispheres of 10 adult male bats. Results indicate that these variables are not significantly lateralized in area DSCF or V1. Additionally, magnopyramidal cells (i.e., the largest 10% of neurons from both hemispheres) were not asymmetric in their frequency of distribution at the population level. Although several individual bats had asymmetric neuron distributions, consistent hemispheric bias was not evident. Absence of population-level microstructural asymmetry in area DSCF of mustached bats suggests alternative evolutionary scenarios including: (1) microstructural lateralization of auditory cortical circuitry may be a unique adaptation for human language, and (2) the specialized biosonar function of mustached bat auditory cortex may require symmetrical cytoarchitectural structure. Resolution of these alternatives will require further data on the microstructure of auditory cortex in species with lateralized perception of acoustic social communication. PMID:15910775

  11. Ventral tegmental area activation promotes firing precision and strength through circuit inhibition in the primary auditory cortex

    OpenAIRE

    Yi Zhou

    2014-01-01

    The activation of the ventral tegmental area (VTA) can rebuild the tonotopic representation in the primary auditory cortex (A1), but the cellular mechanisms remain largely unknown. Here, we investigated the firing patterns and membrane potential dynamics of neurons in A1 under the influence of VTA activation using in vivo intracellular recording. We found that VTA activation can significantly reduce the variability of sound evoked responses and promote the firing precision and strength of A1 ...

  12. 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...

  13. Suppression to visual, auditory and gustatory stimuli habituates normally in rats with excitotoxic lesions of the perirhinal cortex

    OpenAIRE

    Robinson, Jasper; Sanderson, David J.; Aggleton, John P.; Jenkins, Trisha A.

    2009-01-01

    In 3 habituation experiments, rats with excitotoxic lesions of the perirhinal cortex were found to be indistinguishable from control rats. Two of the habituation experiments examined the habituation of suppression of responding on an appetitive, instrumental baseline. One of those experiments used stimuli selected from the visual modality (lights), the other used auditory stimuli. The third experiment examined habituation of suppression of novel-flavored water consumption. In contrast to the ...

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Response of SII cortex to ipsilateral, contralateral and bilateral flutter stimulation in the cat

    Directory of Open Access Journals (Sweden)

    Favorov Oleg

    2005-02-01

    Full Text Available Abstract Background A distinctive property of SII is that it is the first cortical stage of the somatosensory projection pathway that integrates information arising from both sides of the body. However, there is very little known about how inputs across the body mid-line are processed within SII. Results Optical intrinsic signal imaging was used to evaluate the response of primary somatosensory cortex (SI and SII in the same hemisphere to 25 Hz sinusoidal vertical skin displacement stimulation ("skin flutter" applied contralaterally, ipsilaterally, and bilaterally to the central pads of the forepaws. A localized increase in absorbance in both SI and SII was evoked by both contralateral and bilateral flutter stimulation. Ipsilateral flutter stimulation evoked a localized increase in absorbance in SII, but not in SI. The SII region that responded with an increase in absorbance to ipsilateral stimulation was posterior to the region in which absorbance increased maximally in response to stimulation of the contralateral central pad. Additionally, in the posterior SII region that responded maximally to ipsilateral stimulation of the central pad, bilateral central pad stimulation approximated a linear summation of the SII responses to independent stimulation of the contralateral and ipsilateral central pads. Conversely, in anterior SII (the region that responded maximally to contralateral stimulation, bilateral stimulation was consistently less than the response evoked from the contralateral central pad. Conclusions The results indicate that two regions located at neighboring, but distinctly different A-P levels of the anterior ectosylvian gyrus process input from opposite sides of the body midline in very different ways. The results suggest that the SII cortex, in the cat, can be subdivided into at least two functionally distinct regions and that these functionally distinct regions demonstrate a laterality preference within SII.

  16. Mapping the after-effects of theta burst stimulation on the human auditory cortex with functional imaging.

    Science.gov (United States)

    Andoh, Jamila; Zatorre, Robert J

    2012-01-01

    Auditory cortex pertains to the processing of sound, which is at the basis of speech or music-related processing. However, despite considerable recent progress, the functional properties and lateralization of the human auditory cortex are far from being fully understood. Transcranial Magnetic Stimulation (TMS) is a non-invasive technique that can transiently or lastingly modulate cortical excitability via the application of localized magnetic field pulses, and represents a unique method of exploring plasticity and connectivity. It has only recently begun to be applied to understand auditory cortical function. An important issue in using TMS is that the physiological consequences of the stimulation are difficult to establish. Although many TMS studies make the implicit assumption that the area targeted by the coil is the area affected, this need not be the case, particularly for complex cognitive functions which depend on interactions across many brain regions. One solution to this problem is to combine TMS with functional Magnetic resonance imaging (fMRI). The idea here is that fMRI will provide an index of changes in brain activity associated with TMS. Thus, fMRI would give an independent means of assessing which areas are affected by TMS and how they are modulated. In addition, fMRI allows the assessment of functional connectivity, which represents a measure of the temporal coupling between distant regions. It can thus be useful not only to measure the net activity modulation induced by TMS in given locations, but also the degree to which the network properties are affected by TMS, via any observed changes in functional connectivity. Different approaches exist to combine TMS and functional imaging according to the temporal order of the methods. Functional MRI can be applied before, during, after, or both before and after TMS. Recently, some studies interleaved TMS and fMRI in order to provide online mapping of the functional changes induced by TMS. However, this

  17. [Effects of ketamine and urethane on stimulation-induced c-fos expression in neurons of cat visual cortex].

    Science.gov (United States)

    Wang, Ke; Zhu, Hui; Chen, Cui-Yun; Li, Peng; Jin, Cai-Hong; Wang, Zi-Lu; Jiang, San; Hua, Tian-Miao

    2013-12-01

    The effects of ketamine and urethane on neuronal activities remain in debate. As a member of immediate early genes family, the expression of c-fos is stimulation dependent and could be treated as an index to evaluate the strength of neural activities. In this study, SABC immunohistochemical techniques were applied to compare the c-fos expression in neurons of the primary visual cortex (V1) of cats and therefore, to evaluate the effects of acute anesthesia with ketamine HCl and uethane on inhibiting neural activities. Our results showed that compared with control cats, there were no significant differences with the average densities of Nissl-stained V1 neurons in each cortical layers of either urethane or ketamine anesthetized cats. In urethane anesthetized cats, neither the average densities nor the immunoreactive intensities of c-fos positive V1 neurons showed significant difference with that of control ones. However, both the average densities and immunoreactive intensities of c-fos positive V1 neurons in ketamine anesthetized cats decreased significantly compared with that of control and urethane anesthetized cats. These results suggested that ketamine has strong inhibitory effects on the activities of visual cortical neurons, whereas urethane did not. PMID:24415690

  18. Oxidative metabolic activity of cerebral cortex after fluid-percussion head injury in the cat.

    Science.gov (United States)

    Duckrow, R B; LaManna, J C; Rosenthal, M; Levasseur, J E; Patterson, J L

    1981-05-01

    To assess the metabolic and vascular effects of head trauma, fluid-percussion pressure waves were transmitted to the brains of anesthetized, paralyzed, and artificially ventilated cats. Changes in the redox state of cytochrome a,a3, and relative local blood volume were measured in situ by dual-wavelength reflection spectrophotometry of the cortical surface viewed through an acrylic cranial window implanted within the closed skull. Initial fluid-percussion impacts of 0.5 to 2.8 atm peak pressure produced consistent transient oxidation of cytochrome a,a3 and increases of cortical blood volume. These changes occurred despite the presence of transient posttraumatic hypotension i some cases. Also, impact-induced alterations of vascular tone occurred, independent of the presence or absence of transient hypertension in the posttraumatic period. These data demonstrate that hypoxia does not play a role in the immediate posttraumatic period in cerebral cortex, and are consistent with the idea that after injury there is increased cortical energy conservation. These data also support the concept that head trauma alters the relationship of metabolism and cerebral circulation in the period immediately after injury. PMID:7229699

  19. Effects of weak amplitude-modulated microwave fields on calcium efflux from awake cat cerebral cortex

    International Nuclear Information System (INIS)

    Calcium (45Ca2+) efflux was studied from preloaded cortex in cats immobilized under local anesthesia, and exposed to a 3.0-mW/cm2 450-MHz field, sinusoidally amplitude modulated at 16 Hz modulation depth 85%). Tissue dosimetry showed a field of 33 V/m in the interhemispheric fissure (rate of energy deposition 0.29 W/kg). Field exposure lasted 60 min. By comparison with controls, efflux curves from field exposed brains were disrupted by waves of increased 45Ca2+ efflux. These waves were irregular in amplitude and duration, but many exhibited periods of 20-30 min. They continued into the postexposure period. Binomial probability analysis indicates that the field-exposed efflux curves constitute a different population from controls at a confidence level of 0.96. In about 70% of cases, initiation of field exposure was followed by increased end-tidal CO2 excretion for about 5 min. However, hypercapnea induced by hypoventilation did not elicit increased 45Ca2+ efflux. Thus this increase with exposure does not appear to arise as a secondary effect of raised cerebral CO2 levels. Radioactivity measurements in cortical samples after superfusion showed 45Ca2+ penetration at about 1.7 mm/hr, consistent with diffusion of the ion in free solution

  20. Feedforward and feedback projections of caudal belt and parabelt areas of auditory cortex: refining the hierarchical model

    Directory of Open Access Journals (Sweden)

    TroyAHackett

    2014-04-01

    Full Text Available Our working model of the primate auditory cortex recognizes three major regions (core, belt, parabelt, subdivided into thirteen areas. The connections between areas are topographically ordered in a manner consistent with information flow along two major anatomical axes: core-belt-parabelt and caudal-rostral. Remarkably, most of the connections supporting this model were revealed using retrograde tracing techniques. Little is known about laminar circuitry, as anterograde tracing of axon terminations has rarely been used. The purpose of the present study was to examine the laminar projections of three areas of auditory cortex, pursuant to analysis of all areas. The selected areas were: middle lateral belt (ML; caudomedial belt (CM; and caudal parabelt (CPB. Injections of anterograde tracers yielded data consistent with major features of our model, and also new findings that compel modifications. Results supporting the model were: 1 feedforward projection from ML and CM terminated in CPB; 2 feedforward projections from ML and CPB terminated in rostral areas of the belt and parabelt; and 3 feedback projections typified inputs to the core region from belt and parabelt. At odds with the model was the convergence of feedforward inputs into rostral medial belt from ML and CPB. This was unexpected since CPB is at a higher stage of the processing hierarchy, with mainly feedback projections to all other belt areas. Lastly, extending the model, feedforward projections from CM, ML, and CPB overlapped in the temporal parietal occipital area (TPO in the superior temporal sulcus, indicating significant auditory influence on sensory processing in this region. The combined results refine our working model and highlight the need to complete studies of the laminar inputs to all areas of auditory cortex. Their documentation is essential for developing informed hypotheses about the neurophysiological influences of inputs to each layer and area.

  1. Avalanche analysis from multi-electrode ensemble recordings in cat, monkey and human cerebral cortex during wakefulness and sleep.

    Directory of Open Access Journals (Sweden)

    Nima eDehghani

    2012-08-01

    Full Text Available Self-organized critical states are found in many natural systems, from earthquakes to forest fires, they have also been observed in neural systems, particularly, in neuronal cultures. However, the presence of critical states in the awake brain remains controversial. Here, we compared avalanche analyses performed on different in vivo preparations during wakefulness, slow-wave sleep and REM sleep, using high-density electrode arrays in cat motor cortex (96 electrodes, monkey motor cortex and premotor cortex and human temporal cortex (96 electrodes in epileptic patients. In neuronal avalanches defined from units (up to 160 single units, the size of avalanches never clearly scaled as power-law, but rather scaled exponentially or displayed intermediate scaling. We also analyzed the dynamics of local field potentials (LFPs and in particular LFP negative peaks (nLFPs among the different electrodes (up to 96 sites in temporal cortex or up to 128 sites in adjacent motor and pre-motor cortices. In this case, the avalanches defined from nLFPs displayed power-law scaling in double logarithmic representations, as reported previously in monkey. However, avalanche defined as positive LFP (pLFP peaks, which are less directly related to neuronal firing, also displayed apparent power-law scaling. Closer examination of this scaling using the more reliable cumulative distribution function (CDF and other rigorous statistical measures, did not confirm power-law scaling. The same pattern was seen for cats, monkey and human, as well as for different brain states of wakefulness and sleep. We also tested other alternative distributions. Multiple exponential fitting yielded optimal fits of the avalanche dynamics with bi-exponential distributions. Collectively, these results show no clear evidence for power-law scaling or self-organized critical states in the awake and sleeping brain of mammals, from cat to man.

  2. Morphological properties of nociceptive and non-nociceptive neurons in primary somatic cerebral cortex (SI) of cat

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    With the techniques of intracellular recording and labelling, we investigated pain sensation and modulation of the somatic cortical cortex at the neuron's level. After observing the evoked potentials from stimulating the saphenous nerves (SN) of 654 neurons in SI area of the cats, we labelled 30 of the neurons with Neurobiotin to preserve the distribution and the morphologic characteristics of the neurons in the cortex. Based on the tridimensional reconstruction in addition to the eletrophysiological functions, we found clear morphological distinctions between nociceptive and non-nociceptive neurons (P<0.01). This result provided new experimental material to illustrate the function of nociceptive neurons in somatosensory cortex (SI) and presented further evidence to support the "specificity theory" of pain sensation in terms of morphology.

  3. Descending projections from auditory cortex to excitatory and inhibitory cells in the nucleus of the brachium of the inferior colliculus

    Directory of Open Access Journals (Sweden)

    Jeffrey Garrett Mellott

    2014-10-01

    Full Text Available Descending projections from the auditory cortex (AC terminate in subcortical auditory centers from the medial geniculate nucleus (MG to the cochlear nucleus, allowing the AC to modulate the processing of acoustic information at many levels of the auditory system. The nucleus of the brachium of the inferior colliculus (NBIC is a large midbrain auditory nucleus that is a target of these descending cortical projections. The NBIC is a source of several auditory projections, including an ascending projection to the MG. This ascending projection appears to originate from both excitatory and inhibitory NBIC cells, but whether the cortical projections contact either of these cell groups is unknown. In this study, we first combined retrograde tracing and immunochemistry for glutamic acid decarboxylase (GAD, a marker of GABAergic cells to identify GABAergic and non-GABAergic NBIC projections to the MG. Our first result is that GAD-immunopositive cells constitute ~17% of the NBIC to MG projection. We then used anterograde labeling and electron microscopy to examine the AC projection to the NBIC. Our second result is that cortical boutons in the NBIC form synapses with round vesicles and asymmetric synapses, consistent with excitatory effects. Finally, we combined fluorescent anterograde labeling of corticofugal axons with immunochemistry and retrograde labeling of NBIC cells that project to the MG. These final results suggest first that AC axons contact both GAD-negative and GAD-positive NBIC cells and, second, that some of cortically-contacted cells project to the MG. Overall, the results imply that corticofugal projections can modulate both excitatory and inhibitory ascending projections from the NBIC to the auditory thalamus.

  4. Cats

    Science.gov (United States)

    ... those experienced by humans. Cats that hunt wild rodents and rabbits in the western, particularly the southwestern, ... caused by a fungus that can infect skin, hair, and nails of both people and animals. Ringworm ...

  5. Early auditory experience-induced composition/ratio changes of N-methyl-D-aspartate receptor subunit expression and effects of D-2-amino-5-phosphonovaleric acid chronic blockade in rat auditory cortex.

    Science.gov (United States)

    Cui, Yilei; Zhang, Jiping; Cai, Rui; Sun, Xinde

    2009-04-01

    Auditory function can be affected by many factors, including environment and experience. In this study, we investigated whether early auditory experience mediates the regulation of the composition/ratio changes of the N-methyl-D-aspartic acid (NMDA) receptor subunits during development of the rat auditory cortex. We found that early sound exposure can increase expression of the NMDA receptor subunits and increase the composition/ratios of NMDA receptor subunits during the postnatal critical period. D-2-amino-5-phosphonovaleric acid (D-APV) could block and reverse the auditory experience-mediated changes, and there were marked reductions in expression levels and the composition/ratios of NMDA receptor subunits. These results indicate that the experience-dependent plasticity of the auditory cortex in the critical period during postnatal development has a marked influence on NMDA receptor expression in the rat and that changes in NMDA receptor subunit composition/ratios might mediate the early auditory experience-dependent plasticity crucial to auditory function. PMID:19025773

  6. [Connections between the posterior lateral nucleus of the thalamus and the cortex of the cat suprasylvian gyrus].

    Science.gov (United States)

    Artemenko, D P; Mamonets, T M; Fomovskiĭ, B I

    1975-01-01

    Responses of neurons in the thalamic nucleus lateralis posterior (LP) to the stimulation of area 5b and 21 of the suprasylvian gyrus were studied in unanesthetized immobilized cats. Antidromic responses of these neurons indicate the existence of a direct pathways from LP to area 5b and 21. Such pathways are more extensive to area 5b. Relatively long latencies (1.2--60.0 ms) of antidromic responses show that axons of these neurons are slowly conducting (0.3--16.6 m/s). Short-latent 2--3 ms orthodromic responses to LP neurons indicate the existence of a direct pathway from the suprasylvian cortex to LP. Input to LP from area 5b is more powerful than from area 21. The converence of volleys from both areas is seen in 44% of investigated neurons. The stimulation of the suprasylvian cortex evokes postsynaptic inhibition in the most LP neurons. PMID:1207832

  7. Hierarchical computation in the canonical auditory cortical circuit

    OpenAIRE

    Atencio, Craig A.; Sharpee, Tatyana O.; Schreiner, Christoph E.

    2009-01-01

    Sensory cortical anatomy has identified a canonical microcircuit underlying computations between and within layers. This feed-forward circuit processes information serially from granular to supragranular and to infragranular layers. How this substrate correlates with an auditory cortical processing hierarchy is unclear. We recorded simultaneously from all layers in cat primary auditory cortex (AI) and estimated spectrotemporal receptive fields (STRFs) and associated nonlinearities. Spike-trig...

  8. Hearing Loss Alters Serotonergic Modulation of Intrinsic Excitability in Auditory Cortex

    OpenAIRE

    Rao, Deepti; Basura, Gregory J.; Roche, Joseph; Daniels, Scott; Mancilla, Jaime G.; Manis, Paul B.

    2010-01-01

    Sensorineural hearing loss during early childhood alters auditory cortical evoked potentials in humans and profoundly changes auditory processing in hearing-impaired animals. Multiple mechanisms underlie the early postnatal establishment of cortical circuits, but one important set of developmental mechanisms relies on the neuromodulator serotonin (5-hydroxytryptamine [5-HT]). On the other hand, early sensory activity may also regulate the establishment of adultlike 5-HT receptor expression an...

  9. Auditory Evoked Fields Elicited by Spectral, Temporal, and Spectral–Temporal Changes in Human Cerebral Cortex

    OpenAIRE

    ChristoPantev; HidehikoOkamoto

    2012-01-01

    Natural sounds contain complex spectral components, which are temporally modulated as time-varying signals. Recent studies have suggested that the auditory system encodes spectral and temporal sound information differently. However, it remains unresolved how the human brain processes sounds containing both spectral and temporal changes. In the present study, we investigated human auditory evoked responses elicited by spectral, temporal, and spectral-temporal sound changes by means of magnetoe...

  10. 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

  11. Auditory brain-stem evoked potentials in cat after kainic acid induced neuronal loss. I. Superior olivary complex.

    Science.gov (United States)

    Zaaroor, M; Starr, A

    1991-01-01

    Auditory brain-stem potentials (ABRs) were studied in cats for up to 45 days after kainic acid had been injected unilaterally or bilaterally into the superior olivary complex (SOC) to produce neuronal destruction while sparing fibers of passage and the terminals of axons of extrinsic origin connecting to SOC neurons. The components of the ABR in cat were labeled by their polarity at the vertex (P, for positive) and their order of appearance (the arabic numerals 1, 2, etc.). Component P1 can be further subdivided into 2 subcomponents labeled P1a and P1b. The correspondences we have assumed between the ABR components in cat and man are indicated by providing a Roman numeral designation for the human component in parentheses following the feline notation, e.g., P4 (V). With bilateral SOC destruction, there was a significant and marked attenuation of waves P2 (III), P3 (IV), P4 (V), P5 (VI), and the sustained potential shift (SPS) amounting to as much as 80% of preoperative values. Following unilateral SOC destruction the attenuation of many of these same ABR components, in response to stimulation of either ear, was up to 50%. No component of the ABR was totally abolished even when the SOC was lesioned 100% bilaterally. In unilaterally lesioned cats with extensive neuronal loss (greater than 75%) the latencies of the components beginning at P3 (IV) were delayed to stimulation of the ear ipsilateral to the injection site but not to stimulation of the ear contralateral to the injection. Binaural interaction components of the ABR were affected in proportion to the attenuation of the ABR. These results are compatible with multiple brain regions contributing to the generation of the components of the ABR beginning with P2 (III) and that components P3 (IV), P4 (V), and P5 (VI) and the sustained potential shift depend particularly on the integrity of the neurons of the SOC bilaterally. The neurons of the lateral subdivision (LSO) and the medial nucleus of the trapezoid body

  12. Modulatory Effects of Spectral Energy Contrasts on Lateral Inhibition in the Human Auditory Cortex: An MEG Study

    Science.gov (United States)

    Stein, Alwina; Engell, Alva; Okamoto, Hidehiko; Wollbrink, Andreas; Lau, Pia; Wunderlich, Robert; Rudack, Claudia; Pantev, Christo

    2013-01-01

    We investigated the modulation of lateral inhibition in the human auditory cortex by means of magnetoencephalography (MEG). In the first experiment, five acoustic masking stimuli (MS), consisting of noise passing through a digital notch filter which was centered at 1 kHz, were presented. The spectral energy contrasts of four MS were modified systematically by either amplifying or attenuating the edge-frequency bands around the notch (EFB) by 30 dB. Additionally, the width of EFB amplification/attenuation was varied (3/8 or 7/8 octave on each side of the notch). N1m and auditory steady state responses (ASSR), evoked by a test stimulus with a carrier frequency of 1 kHz, were evaluated. A consistent dependence of N1m responses upon the preceding MS was observed. The minimal N1m source strength was found in the narrowest amplified EFB condition, representing pronounced lateral inhibition of neurons with characteristic frequencies corresponding to the center frequency of the notch (NOTCH CF) in secondary auditory cortical areas. We tested in a second experiment whether an even narrower bandwidth of EFB amplification would result in further enhanced lateral inhibition of the NOTCH CF. Here three MS were presented, two of which were modified by amplifying 1/8 or 1/24 octave EFB width around the notch. We found that N1m responses were again significantly smaller in both amplified EFB conditions as compared to the NFN condition. To our knowledge, this is the first study demonstrating that the energy and width of the EFB around the notch modulate lateral inhibition in human secondary auditory cortical areas. Because it is assumed that chronic tinnitus is caused by a lack of lateral inhibition, these new insights could be used as a tool for further improvement of tinnitus treatments focusing on the lateral inhibition of neurons corresponding to the tinnitus frequency, such as the tailor-made notched music training. PMID:24349019

  13. Bimodal stimulus timing-dependent plasticity in primary auditory cortex is altered after noise exposure with and without tinnitus.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2015-12-01

    Central auditory circuits are influenced by the somatosensory system, a relationship that may underlie tinnitus generation. In the guinea pig dorsal cochlear nucleus (DCN), pairing spinal trigeminal nucleus (Sp5) stimulation with tones at specific intervals and orders facilitated or suppressed subsequent tone-evoked neural responses, reflecting spike timing-dependent plasticity (STDP). Furthermore, after noise-induced tinnitus, bimodal responses in DCN were shifted from Hebbian to anti-Hebbian timing rules with less discrete temporal windows, suggesting a role for bimodal plasticity in tinnitus. Here, we aimed to determine if multisensory STDP principles like those in DCN also exist in primary auditory cortex (A1), and whether they change following noise-induced tinnitus. Tone-evoked and spontaneous neural responses were recorded before and 15 min after bimodal stimulation in which the intervals and orders of auditory-somatosensory stimuli were randomized. Tone-evoked and spontaneous firing rates were influenced by the interval and order of the bimodal stimuli, and in sham-controls Hebbian-like timing rules predominated as was seen in DCN. In noise-exposed animals with and without tinnitus, timing rules shifted away from those found in sham-controls to more anti-Hebbian rules. Only those animals with evidence of tinnitus showed increased spontaneous firing rates, a purported neurophysiological correlate of tinnitus in A1. Together, these findings suggest that bimodal plasticity is also evident in A1 following noise damage and may have implications for tinnitus generation and therapeutic intervention across the central auditory circuit. PMID:26289461

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

    Science.gov (United States)

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

    2015-10-01

    Auditory deprivation and the restoration of hearing via a cochlear implant (CI) can induce functional plasticity in auditory cortical areas. How these plastic changes affect the ability to integrate combined auditory (A) and visual (V) information is not yet well understood. In the present study, we used electroencephalography (EEG) to examine whether age, temporary deafness and altered sensory experience with a CI can affect audio-visual (AV) interactions in post-lingually deafened CI users. Young and elderly CI users and age-matched NH listeners performed a speeded response task on basic auditory, visual and audio-visual stimuli. Regarding the behavioral results, a redundant signals effect, that is, faster response times to cross-modal (AV) than to both of the two modality-specific stimuli (A, V), was revealed for all groups of participants. Moreover, in all four groups, we found evidence for audio-visual integration. Regarding event-related responses (ERPs), we observed a more pronounced visual modulation of the cortical auditory response at N1 latency (approximately 100 ms after stimulus onset) in the elderly CI users when compared with young CI users and elderly NH listeners. Thus, elderly CI users showed enhanced audio-visual binding which may be a consequence of compensatory strategies developed due to temporary deafness and/or degraded sensory input after implantation. These results indicate that the combination of aging, sensory deprivation and CI facilitates the coupling between the auditory and the visual modality. We suggest that this enhancement in multisensory interactions could be used to optimize auditory rehabilitation, especially in elderly CI users, by the application of strong audio-visually based rehabilitation strategies after implant switch-on. PMID:26302946

  15. Three dimensional morphometric analyses of axon terminals early changes induced by methylmercury intoxication in the adult cat striate cortex.

    Science.gov (United States)

    de Oliveira, Ricardo Bezerra; Gomes Leal, Wallace; Picanço-Diniz, Domingos Luis Wanderley; Torres Neto, João Bento; Lins, Nara; Malm, Olaf; Picanço-Diniz, Cristovam W

    2008-12-01

    The aim of the present report is to investigate in detail morphometric changes of axon terminals of area 17 of adult cat induced by methylmercury intoxication. Six adult male cats (Felix catus), with 12 h day-light cycle and ad libitum water and food regimen, received a single dose of MeHgCl (6.4 mg/kg) dissolved in milk, whereas control subjects (n=6) received only milk. After 30 days, biocytin iontophoretic injections were done into the area 17, (Horsley-Clark coordinates between AP 3.0-6.0) on the crown of the lateral gyrus, near the border with area 18. MeHg and inorganic Hg (Hgi) concentrations were measured in the brain parenchyma of intoxicated cats and corresponded on average to 1.39+/-0.3 and 6.79+/-0.6 ppm (mean+/-s.e.m.) respectively. Twenty four hours after iontophoresis, aldehyde fixed brain sections (200 microm thick), were processed to reveal biocytin labeled terminals. Axonal microscopic 3D reconstructions using Neurolucida software (Microbright Systems Inc.) allowed estimations of boutons, branching points and segment densities for each terminal. Cluster analysis of morphometric axonal features from control and intoxicated group revealed, two distinct axon families (Type I and II) as described elsewhere. Total density values of boutons, branching points and segment densities of intoxicated group, decreased 81, 59 and 91% respectively, as compared to the control group (ANOVA two-way, Bonferroni a priori test pintoxication in the visual cortex. PMID:18835550

  16. Auditory evoked fields elicited by spectral, temporal, and spectral-temporal changes in human cerebral cortex

    Directory of Open Access Journals (Sweden)

    ChristoPantev

    2012-05-01

    Full Text Available Natural sounds contain complex spectral components, which are temporally modulated as time-varying signals. Recent studies have suggested that the auditory system encodes spectral and temporal sound information differently. However, it remains unresolved how the human brain processes sounds containing both spectral and temporal changes. In the present study, we investigated human auditory evoked responses elicited by spectral, temporal, and spectral-temporal sound changes by means of magnetoencephalography (MEG. The auditory evoked responses elicited by the spectral-temporal change were very similar to those elicited by the spectral change, but those elicited by the temporal change were delayed by 30 – 50 ms and differed from the others in morphology. The results suggest that human brain responses corresponding to spectral sound changes precede those corresponding to temporal sound changes, even when the spectral and temporal changes occur simultaneously.

  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. Auditory brain-stem evoked potentials in cat after kainic acid induced neuronal loss. II. Cochlear nucleus.

    Science.gov (United States)

    Zaaroor, M; Starr, A

    1991-01-01

    Auditory brain-stem potentials (ABRs) were studied in cats for up to 6 weeks after kainic acid had been injected unilaterally into the cochlear nucleus (CN) producing extensive neuronal destruction. The ABR components were labeled by the polarity at the vertex (P, for positive) and their order of appearance (the arabic numerals 1, 2, etc.). Component P1 can be further subdivided into 2 subcomponents, P1a and P1b. The assumed correspondence between the ABR components in cat and man is indicated by providing human Roman numeral designations in parentheses following the feline notation, e.g., P2 (III). To stimulation of the ear ipsilateral to the injection, the ABR changes consisted of a loss of components P2 (III) and P3 (IV), and an attenuation and prolongation of latency of components P4 (V) and P5 (VI). The sustained potential shift from which the components arose was not affected. Wave P1a (I) was also slightly but significantly attenuated compatible with changes of excitability of nerve VIII in the cochlea secondary to cochlear nucleus destruction. Unexpectedly, to stimulation of the ear contralateral to the injection side, waves P2 (III), P3 (IV), and P4 (V) were also attenuated and delayed in latency but to a lesser degree than to stimulation of the ear ipsilateral to the injection. Changes in binaural interaction of the ABR following cochlear nucleus lesions were similar to those produced in normal animals by introducing a temporal delay of the input to one ear. The results of the present set of studies using kainic acid to induce neuronal loss in auditory pathway when combined with prior lesion and recording experiments suggest that each of the components of the ABR requires the integrity of an anatomically diffuse system comprising a set of neurons, their axons, and the neurons on which they terminate. Disruption of any portion of the system will alter the amplitude and/or the latency of that component. PMID:1716569

  19. Asymmetrical interhemispheric connections develop in cat visual cortex after early unilateral convergent strabismus: Anatomy, physiology and mechanisms

    Directory of Open Access Journals (Sweden)

    Emmanuel eBui Quoc

    2012-01-01

    Full Text Available In the mammalian primary visual cortex, the corpus callosum contributes to the unification of the visual hemifields that project to the two hemispheres. Its development depends on visual experience. When the latter is abnormal, callosal connections must undergo dramatic anatomical and physiological changes. However, such data are sparse and incomplete. Thus, little is known about the consequences of abnormal postnatal visual experience on the development of callosal connections and their role in unifying representation of the two hemifields. Here, the effects of early unilateral convergent strabismus (a model of abnormal visual experience were fully characterized with respect to the development of the callosal connections in cat visual cortex, an experimental model for humans. Electrophysiological responses and 3D reconstruction of single callosal axons show that abnormally asymmetrical callosal connections develop after unilateral convergent strabismus, resulting from an extension of axonal branches of specific orders in the hemisphere ipsilateral to the deviated eye and a decreased number of nodes and terminals in the other (ipsilateral to the non deviated eye. Furthermore this asymmetrical organization prevents the establishment of a unifying representation of the two visual hemifields. As a general rule, we suggest that crossed and uncrossed retino-geniculo-cortical pathways contribute in succession to the development of the callosal maps in visual cortex.

  20. Recording of neuronal activity in the rat auditory cortex with chronic multielectrode probe

    Czech Academy of Sciences Publication Activity Database

    Popelář, Jiří; Grécová, Jolana; Nikitin, N.I.; Rybalko, Natalia; Syka, Josef

    Geneva : Federation of European Neurosciences Societies, 2008. 188.20. [FENS. Forum of European Neuroscience /6./. 12.07.2008-16.07.2008, Geneva] R&D Projects: GA ČR GA309/07/1336; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390512 Keywords : Sensory and motor systems * Auditory Subject RIV: FH - Neurology

  1. Auditory Attraction: Activation of Visual Cortex by Music and Sound in Williams Syndrome

    Science.gov (United States)

    Thornton-Wells, Tricia A.; Cannistraci, Christopher J.; Anderson, Adam W.; Kim, Chai-Youn; Eapen, Mariam; Gore, John C.; Blake, Randolph; Dykens, Elisabeth M.

    2010-01-01

    Williams syndrome is a genetic neurodevelopmental disorder with a distinctive phenotype, including cognitive-linguistic features, nonsocial anxiety, and a strong attraction to music. We performed functional MRI studies examining brain responses to musical and other types of auditory stimuli in young adults with Williams syndrome and typically…

  2. Specificity of auditory-guided visual perceptual learning suggests crossmodal plasticity in early visual cortex

    OpenAIRE

    Beer, Anton L.; Watanabe, Takeo

    2009-01-01

    Sounds modulate visual perception. Blind humans show altered brain activity in early visual cortex. However, it is still unclear whether crossmodal activity in visual cortex results from unspecific top-down feedback, a lack of visual input, or genuinely reflects crossmodal interactions at early sensory levels. We examined how sounds affect visual perceptual learning in sighted adults. Visual motion discrimination was tested prior to and following eight sessions in which observers were exposed...

  3. Temporal encoding precision of bat auditory neurons tuned to target distance deteriorates on the way to the cortex.

    Science.gov (United States)

    Macías, Silvio; Hechavarría, Julio C; Kössl, Manfred

    2016-03-01

    During echolocation, bats estimate distance to avoid obstacles and capture moving prey. The primary distance cue is the delay between the bat's emitted echolocation pulse and the return of an echo. In the bat's auditory system, echo delay-tuned neurons that only respond to pulse-echo pairs having a specific echo delay serve target distance calculation. Accurate prey localization should benefit from the spike precision in such neurons. Here we show that delay-tuned neurons in the inferior colliculus of the mustached bat respond with higher temporal precision, shorter latency and shorter response duration than those of the auditory cortex. Based on these characteristics, we suggest that collicular neurons are best suited for a fast and accurate response that could lead to fast behavioral reactions while cortical neurons, with coarser temporal precision and longer latencies and response durations could be more appropriate for integrating acoustic information over time. The latter could be important for the formation of biosonar images. PMID:26785850

  4. Trajectory of the main GABAergic interneuron populations from early development to old age in the rat primary auditory cortex

    Directory of Open Access Journals (Sweden)

    Lydia eOuellet

    2014-06-01

    Full Text Available In both humans and rodents, decline in cognitive function is a hallmark of the aging process, the basis for this decrease has yet to be fully characterized. However, using aged rodent models, deficits in auditory processing have been associated with significant decreases in inhibitory signaling attributed to a loss of GABAergic interneurons. Not only are these interneurons crucial for pattern detection and other large-scale population dynamics, but they have also been linked to mechanisms mediating plasticity and learning, making them a prime candidate for study and modelling of modifications to cortical communication pathways in neurodegenerative diseases. Using the rat primary auditory cortex (A1 as a model, we probed the known markers of GABAergic interneurons with immunohistological methods, using antibodies against gamma aminobutyric acid (GABA, parvalbumin (PV, somatostatin (SOM, calretinin (CR, vasoactive intestinal peptide (VIP, choline acetyltransferase (ChAT, neuropeptide Y (NPY and cholecystokinin (CCK to document the changes observed in interneuron populations across the rat’s lifespan. This analysis provided strong evidence that several but not all GABAergic neurons were affected by the aging process, showing most dramatic changes in expression of parvalbumin (PV and somatostatin (SOM expression. With this evidence, we show how understanding these trajectories of cell counts may be factored into a simple model to quantify changes in inhibitory signalling across the course of life, which may be applied as a framework for creating more advanced simulations of interneuronal implication in normal cerebral processing, normal aging, or pathological processes.

  5. Lateralization of Music Processing with Noises in the Auditory Cortex: An fNIRS Study

    OpenAIRE

    Hendrik eSantosa; Melissa Jiyoun Hong; Keum-Shik eHong

    2014-01-01

    The present study is to determine the effects of background noise on the hemispheric lateralization in music processing by exposing fourteen subjects to four different auditory environments: music segments only, noise segments only, music+noise segments, and the entire music interfered by noise segments. The hemodynamic responses in both hemispheres caused by the perception of music in 10 different conditions were measured using functional near-infrared spectroscopy. As a feature to distingui...

  6. Lateralization of music processing with noises in the auditory cortex: an fNIRS study

    OpenAIRE

    Santosa, Hendrik; Hong, Melissa Jiyoun; Hong, Keum-Shik

    2014-01-01

    The present study is to determine the effects of background noise on the hemispheric lateralization in music processing by exposing 14 subjects to four different auditory environments: music segments only, noise segments only, music + noise segments, and the entire music interfered by noise segments. The hemodynamic responses in both hemispheres caused by the perception of music in 10 different conditions were measured using functional near-infrared spectroscopy. As a feature to distinguish s...

  7. Exploring the extent and function of higher-order auditory cortex in rhesus monkeys.

    Science.gov (United States)

    Poremba, Amy; Mishkin, Mortimer

    2007-07-01

    Just as cortical visual processing continues far beyond the boundaries of early visual areas, so too does cortical auditory processing continue far beyond the limits of early auditory areas. In passively listening rhesus monkeys examined with metabolic mapping techniques, cortical areas reactive to auditory stimulation were found to include the entire length of the superior temporal gyrus (STG) as well as several other regions within the temporal, parietal, and frontal lobes. Comparison of these widespread activations with those from an analogous study in vision supports the notion that audition, like vision, is served by several cortical processing streams, each specialized for analyzing a different aspect of sensory input, such as stimulus quality, location, or motion. Exploration with different classes of acoustic stimuli demonstrated that most portions of STG show greater activation on the right than on the left regardless of stimulus class. However, there is a striking shift to left-hemisphere "dominance" during passive listening to species-specific vocalizations, though this reverse asymmetry is observed only in the region of temporal pole. The mechanism for this left temporal pole "dominance" appears to be suppression of the right temporal pole by the left hemisphere, as demonstrated by a comparison of the results in normal monkeys with those in split-brain monkeys. PMID:17321703

  8. 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

  9. Interplay of orientation selectivity and the power of low- and high-gamma bands in the cat primary visual cortex.

    Science.gov (United States)

    Bharmauria, Vishal; Bachatene, Lyes; Ouelhazi, Afef; Cattan, Sarah; Chanauria, Nayan; Etindele-Sosso, Faustin Armel; Rouat, Jean; Molotchnikoff, Stéphane

    2016-05-01

    Gamma oscillations are ubiquitous in brain and are believed to be inevitable for information processing in brain. Here, we report that distinct bands (low, 30-40Hz and high gamma, 60-80Hz) of stimulus-triggered gamma oscillations are systematically linked to the orientation selectivity index (OSI) of neurons in the cat primary visual cortex. The gamma-power is high for the highly selective neurons in the low-gamma band, whereas it is high for the broadly selective neurons in the high-gamma band. We suggest that the low-gamma band is principally implicated in feed-forward excitatory flow, whereas the high-gamma band governs the flow of this excitation. PMID:27033667

  10. The auditory cross-section (AXS) test battery: A new way to study afferent/efferent relations linking body periphery (ear, voice, heart) with brainstem and cortex

    Science.gov (United States)

    Lauter, Judith

    2002-05-01

    Several noninvasive methods are available for studying the neural bases of human sensory-motor function, but their cost is prohibitive for many researchers and clinicians. The auditory cross section (AXS) test battery utilizes relatively inexpensive methods, yet yields data that are at least equivalent, if not superior in some applications, to those generated by more expensive technologies. The acronym emphasizes access to axes-the battery makes it possible to assess dynamic physiological relations along all three body-brain axes: rostro-caudal (afferent/efferent), dorso-ventral, and right-left, on an individually-specific basis, extending from cortex to the periphery. For auditory studies, a three-level physiological ear-to-cortex profile is generated, utilizing (1) quantitative electroencephalography (qEEG); (2) the repeated evoked potentials version of the auditory brainstem response (REPs/ABR); and (3) otoacoustic emissions (OAEs). Battery procedures will be explained, and sample data presented illustrating correlated multilevel changes in ear, voice, heart, brainstem, and cortex in response to circadian rhythms, and challenges with substances such as antihistamines and Ritalin. Potential applications for the battery include studies of central auditory processing, reading problems, hyperactivity, neural bases of voice and speech motor control, neurocardiology, individually-specific responses to medications, and the physiological bases of tinnitus, hyperacusis, and related treatments.

  11. The effects of acute alcohol exposure on the response properties of neurons in visual cortex area 17 of cats

    International Nuclear Information System (INIS)

    Physiological and behavioral studies have demonstrated that a number of visual functions such as visual acuity, contrast sensitivity, and motion perception can be impaired by acute alcohol exposure. The orientation- and direction-selective responses of cells in primary visual cortex are thought to participate in the perception of form and motion. To investigate how orientation selectivity and direction selectivity of neurons are influenced by acute alcohol exposure in vivo, we used the extracellular single-unit recording technique to examine the response properties of neurons in primary visual cortex (A17) of adult cats. We found that alcohol reduces spontaneous activity, visual evoked unit responses, the signal-to-noise ratio, and orientation selectivity of A17 cells. In addition, small but detectable changes in both the preferred orientation/direction and the bandwidth of the orientation tuning curve of strongly orientation-biased A17 cells were observed after acute alcohol administration. Our findings may provide physiological evidence for some alcohol-related deficits in visual function observed in behavioral studies.

  12. Increased neural correlations in primate auditory cortex during slow-wave sleep

    OpenAIRE

    Issa, Elias B.; Wang, Xiaoqin

    2013-01-01

    During sleep, changes in brain rhythms and neuromodulator levels in cortex modify the properties of individual neurons and the network as a whole. In principle, network-level interactions during sleep can be studied by observing covariation in spontaneous activity between neurons. Spontaneous activity, however, reflects only a portion of the effective functional connectivity that is activated by external and internal inputs (e.g., sensory stimulation, motor behavior, and mental activity), and...

  13. The Emergence of Contrast-Invariant Orientation Tuning in Simple Cells of Cat Visual Cortex

    OpenAIRE

    Finn, Ian M.; Priebe, Nicholas J.; Ferster, David

    2007-01-01

    Simple cells in primary visual cortex exhibit contrast-invariant orientation tuning, in seeming contradiction to feed-forward models relying on lateral geniculate nucleus (LGN) input alone. Contrast invariance has therefore been thought to depend on the presence of intracortical lateral inhibition. In vivo intracellular recordings instead suggest that contrast invariance can be explained by three properties of the excitatory pathway. 1) Depolarizations evoked by orthogonal stimuli are determi...

  14. ON AND OFF DOMAINS OF GENICULATE AFFERENTS IN CAT PRIMARY VISUAL CORTEX

    OpenAIRE

    Jin, J. Z.; Weng, C.; Yeh, C. I.; Gordon, J A; RUTHAZER, E.S.; Stryker, M.P.; Swadlow, H A; Alonso, J M

    2007-01-01

    On- and off-center geniculate afferents form two major channels of visual processing that are thought to converge in the primary visual cortex. However, humans with severely reduced on-responses can have normal visual acuity when tested in a white background, which indicates that off-channels can function relatively independently of on-channels under certain conditions. Consistent with this functional independence of channels, here we demonstrate that on- and off-center geniculate afferents s...

  15. A Postnatal Critical Period for Orientation Plasticity in the Cat Visual Cortex

    OpenAIRE

    Shigeru Tanaka; Toshiki Tani; Jérôme Ribot; Kazunori O'Hashi; Kazuyuki Imamura

    2009-01-01

    Orientation selectivity of primary visual cortical neurons is an important requisite for shape perception. Although numerous studies have been previously devoted to a question of how orientation selectivity is established and elaborated in early life, how the susceptibility of orientation plasticity to visual experience changes in time remains unclear. In the present study, we showed a postnatal sensitive period profile for the modifiability of orientation selectivity in the visual cortex of ...

  16. The responses to illusory contours of neurons in cortex areas 17 and 18 of the cats

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Responses to illusory contours (ICs) were sampled from neurons incortical areas 17 and 18 of the anesthetized cats. For ICs sensitive cells, the differences of receptive field properties were compared when ICs and real contour stimuli were applied. Two hundred orientation or direction selective cells were studied. We find that about 42 percent of these cells were the ICs sensitive cells. Although their orientation or direction tuning curves to ICs bar and real bars were similar, the response modes (especially latency and time course) were different. The cells' responses to ICs were independent of the spatial phases of sinusoidal gratings, which composed the ICs. The cells' optimal spatial frequency to composing gratings the ICs was much higher than the one to moving gratings. Therefore, these cells really responded to the ICs rather than the line ends of composing gratings. For some kinds of velocity-tuning cells, the optimal velocity to moving ICs bar was much lower than the optimal velocity to moving bars. The present results demonstrate that some cells in areas 17 and 18 of cats have the ability to respond to ICs and have different response properties of the receptive fields to ICs and luminance boundaries via different neural mechanisms.

  17. Transient down-regulation of sound-induced c-Fos protein expression in the inferior colliculus after ablation of the auditory cortex

    OpenAIRE

    Cheryl Clarkson; José M Juíz; Merchán, Miguel A.

    2010-01-01

    We tested whether lesions of the excitatory glutamatergic projection from the auditory cortex to the inferior colliculus induce plastic changes in neurons of this nucleus. Changes in neuronal activation in the inferior colliculus deprived unilaterally of the cortico-collicular projection were assessed by quantitative c-Fos immunocytochemistry. Densitometry and stereology measures of sound-induced c-Fos immunoreactivity in the inferior colliculus showed diminished labeling at 1, 15, 90 and 1...

  18. Methylmercury intoxication and histochemical demonstration of NADPH-diaphorase activity in the striate cortex of adult cats

    Directory of Open Access Journals (Sweden)

    Oliveira R.B.

    1998-01-01

    Full Text Available The effects of methylmercury (MeHg on histochemical demonstration of the NADPH-diaphorase (NADPH-d activity in the striate cortex were studied in 4 adult cats. Two animals were used as control. The contaminated animals received 50 ml milk containing 0.42 µg MeHg and 100 g fish containing 0.03 µg MeHg daily for 2 months. The level of MeHg in area 17 of intoxicated animals was 3.2 µg/g wet weight brain tissue. Two cats were perfused 24 h after the last dose (group 1 and the other animals were perfused 6 months later (group 2. After microtomy, sections were processed for NADPHd histochemistry procedures using the malic enzyme method. Dendritic branch counts were performed from camera lucida drawings for control and intoxicated animals (N = 80. Average, standard deviation and Student t-test were calculated for each data group. The concentrations of mercury (Hg in milk, fish and brain tissue were measured by acid digestion of samples, followed by reduction of total Hg in the digested sample to metallic Hg using stannous chloride followed by atomic fluorescence analysis. Only group 2 revealed a reduction of the neuropil enzyme activity and morphometric analysis showed a reduction in dendritic field area and in the number of distal dendrite branches of the NADPHd neurons in the white matter (P<0.05. These results suggest that NADPHd neurons in the white matter are more vulnerable to the long-term effects of MeHg than NADPHd neurons in the gray matter.

  19. Direct current induced short-term modulation of the left dorsolateral prefrontal cortex while learning auditory presented nouns

    Directory of Open Access Journals (Sweden)

    Meyer Martin

    2009-07-01

    Full Text Available Abstract Background Little is known about the contribution of transcranial direct current stimulation (tDCS to the exploration of memory functions. The aim of the present study was to examine the behavioural effects of right or left-hemisphere frontal direct current delivery while committing to memory auditory presented nouns on short-term learning and subsequent long-term retrieval. Methods Twenty subjects, divided into two groups, performed an episodic verbal memory task during anodal, cathodal and sham current application on the right or left dorsolateral prefrontal cortex (DLPFC. Results Our results imply that only cathodal tDCS elicits behavioural effects on verbal memory performance. In particular, left-sided application of cathodal tDCS impaired short-term verbal learning when compared to the baseline. We did not observe tDCS effects on long-term retrieval. Conclusion Our results imply that the left DLPFC is a crucial area involved in short-term verbal learning mechanisms. However, we found further support that direct current delivery with an intensity of 1.5 mA to the DLPFC during short-term learning does not disrupt longer lasting consolidation processes that are mainly known to be related to mesial temporal lobe areas. In the present study, we have shown that the tDCS technique has the potential to modulate short-term verbal learning mechanism.

  20. Lateralization of music processing with noises in the auditory cortex: an fNIRS study

    Science.gov (United States)

    Santosa, Hendrik; Hong, Melissa Jiyoun; Hong, Keum-Shik

    2014-01-01

    The present study is to determine the effects of background noise on the hemispheric lateralization in music processing by exposing 14 subjects to four different auditory environments: music segments only, noise segments only, music + noise segments, and the entire music interfered by noise segments. The hemodynamic responses in both hemispheres caused by the perception of music in 10 different conditions were measured using functional near-infrared spectroscopy. As a feature to distinguish stimulus-evoked hemodynamics, the difference between the mean and the minimum value of the hemodynamic response for a given stimulus was used. The right-hemispheric lateralization in music processing was about 75% (instead of continuous music, only music segments were heard). If the stimuli were only noises, the lateralization was about 65%. But, if the music was mixed with noises, the right-hemispheric lateralization has increased. Particularly, if the noise was a little bit lower than the music (i.e., music level 10~15%, noise level 10%), the entire subjects showed the right-hemispheric lateralization: This is due to the subjects' effort to hear the music in the presence of noises. However, too much noise has reduced the subjects' discerning efforts. PMID:25538583

  1. A network for sensory-motor integration: what happens in the auditory cortex during piano playing without acoustic feedback?

    Science.gov (United States)

    Baumann, Simon; Koeneke, Susan; Meyer, Martin; Lutz, Kai; Jäncke, Lutz

    2005-12-01

    Playing a musical instrument requires efficient auditory as well as motor processing. We provide evidence for the existence of a neuronal network of secondary and higher-order areas belonging to the auditory and motor modality that is important in the integration of auditory and motor domains. PMID:16597763

  2. Effects of torque disturbances on elbow joint movements evoked in unanesthetized cats by microstimulation of the motor cortex.

    Science.gov (United States)

    Kostyukov, A I; Tal'nov, A N

    1991-01-01

    Flexion and extension movements were evoked in the elbow joint of unanesthetized cats by intracortical microstimulation (ICMS) applied to deep layers of the motor cortex (areas 4 and 6). Pulse trains with duration up to 3-4 s, current intensities of 15-50 microA and rates of approximately 100/s were used. Cortically evoked movements (CEMs) were tested mechanically by applying servo-controlled torque disturbances to the joint. The disturbances consisted of two reciprocating sinusoidal pulses of torque with fixed frequencies (1.2 or 3.2 Hz). A pronounced torque-angle hysteresis with long-lasting after-effects was revealed in the presence of the torque disturbances that opposed the CEMs and/or assisted them. Two parameters were introduced to describe the mechanical testing of the CEMs quantitatively: (1) the resulting stiffness (RS) defined during the forward and reverse phases of the disturbed movement as a ratio between the amplitudes of torque wave and the overall change of angle at these phases; (2) uncertainty index (UI) defined as the subtraction of forward and reverse angle changes, which was normalized by the first of these two values. RS was shown to be dependent on the immediate past movement history of the joint, it increased with changes in the direction of movement, and its magnitude during such changes could be several times higher than when the disturbance was in the same direction as the movement.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2065744

  3. Synchrony between orientation-selective neurons is modulated during adaptation-induced plasticity in cat visual cortex

    Directory of Open Access Journals (Sweden)

    Shumikhina Svetlana

    2008-07-01

    Full Text Available Abstract Background Visual neurons respond essentially to luminance variations occurring within their receptive fields. In primary visual cortex, each neuron is a filter for stimulus features such as orientation, motion direction and velocity, with the appropriate combination of features eliciting maximal firing rate. Temporal correlation of spike trains was proposed as a potential code for linking the neuronal responses evoked by various features of a same object. In the present study, synchrony strength was measured between cells following an adaptation protocol (prolonged exposure to a non-preferred stimulus which induce plasticity of neurons' orientation preference. Results Multi-unit activity from area 17 of anesthetized adult cats was recorded. Single cells were sorted out and (1 orientation tuning curves were measured before and following 12 min adaptation and 60 min after adaptation (2 pairwise synchrony was measured by an index that was normalized in relation to the cells' firing rate. We first observed that the prolonged presentation of a non-preferred stimulus produces attractive (58% and repulsive (42% shifts of cell's tuning curves. It follows that the adaptation-induced plasticity leads to changes in preferred orientation difference, i.e. increase or decrease in tuning properties between neurons. We report here that, after adaptation, the neuron pairs that shared closer tuning properties display a significant increase of synchronization. Recovery from adaptation was accompanied by a return to the initial synchrony level. Conclusion We conclude that synchrony reflects the similarity in neurons' response properties, and varies accordingly when these properties change.

  4. Age-related decrease in the mitochondrial sirtuin deacetylase Sirt3 expression associated with ROS accumulation in the auditory cortex of the mimetic aging rat model.

    Directory of Open Access Journals (Sweden)

    Lingling Zeng

    Full Text Available Age-related dysfunction of the central auditory system, also known as central presbycusis, can affect speech perception and sound localization. Understanding the pathogenesis of central presbycusis will help to develop novel approaches to prevent or treat this disease. In this study, the mechanisms of central presbycusis were investigated using a mimetic aging rat model induced by chronic injection of D-galactose (D-Gal. We showed that malondialdehyde (MDA levels were increased and manganese superoxide dismutase (SOD2 activity was reduced in the auditory cortex in natural aging and D-Gal-induced mimetic aging rats. Furthermore, mitochondrial DNA (mtDNA 4834 bp deletion, abnormal ultrastructure and cell apoptosis in the auditory cortex were also found in natural aging and D-Gal mimetic aging rats. Sirt3, a mitochondrial NAD+-dependent deacetylase, has been shown to play a crucial role in controlling cellular reactive oxygen species (ROS homeostasis. However, the role of Sirt3 in the pathogenesis of age-related central auditory cortex deterioration is still unclear. Here, we showed that decreased Sirt3 expression might be associated with increased SOD2 acetylation, which negatively regulates SOD2 activity. Oxidative stress accumulation was likely the result of low SOD2 activity and a decline in ROS clearance. Our findings indicate that Sirt3 might play an essential role, via the mediation of SOD2, in central presbycusis and that manipulation of Sirt3 expression might provide a new approach to combat aging and oxidative stress-related diseases.

  5. Slow wave changes in amygdala to visual, auditory, and social stimuli following lesions of the inferior temporal cortex in squirrel monkey (Saimiri sciureus).

    Science.gov (United States)

    Kling, A S; Lloyd, R L; Perryman, K M

    1987-01-01

    Radiotelemetry of slow wave activity of the amygdala was recorded under a variety of conditions. Power, and the percentage of power in the delta band, increased in response to stimulation. Recordings of monkey vocalizations and slides of ethologically relevant, natural objects produced a greater increase in power than did control stimuli. The responses to auditory stimuli increased when these stimuli were presented in an unrestrained, group setting, yet the responses to the vocalizations remained greater than those following control stimuli. Both the natural auditory and visual stimuli produced a reliable hierarchy with regard to the magnitude of response. Following lesions of inferior temporal cortex, these two hierarchies are disrupted, especially in the auditory domain. Further, these same stimuli, when presented after the lesion, produced a decrease, rather than an increase, in power. Nevertheless, the power recorded from the natural stimuli was still greater than that recorded from control stimuli in that the former produced less of a decrease in power, following the lesion, than did the latter. These data, in conjunction with a parallel report on evoked potentials in the amygdala, before and after cortical lesions, lead us to conclude that sensory information, particularly auditory, available to the amygdala, following the lesion, is substantially the same, and that it is the interpretation of this information, by the amygdala, which is altered by the cortical lesion. PMID:3566692

  6. Supplementary motor area and primary auditory cortex activation in an expert break-dancer during the kinesthetic motor imagery of dance to music.

    Science.gov (United States)

    Olshansky, Michael P; Bar, Rachel J; Fogarty, Mary; DeSouza, Joseph F X

    2015-01-01

    The current study used functional magnetic resonance imaging to examine the neural activity of an expert dancer with 35 years of break-dancing experience during the kinesthetic motor imagery (KMI) of dance accompanied by highly familiar and unfamiliar music. The goal of this study was to examine the effect of musical familiarity on neural activity underlying KMI within a highly experienced dancer. In order to investigate this in both primary sensory and motor planning cortical areas, we examined the effects of music familiarity on the primary auditory cortex [Heschl's gyrus (HG)] and the supplementary motor area (SMA). Our findings reveal reduced HG activity and greater SMA activity during imagined dance to familiar music compared to unfamiliar music. We propose that one's internal representations of dance moves are influenced by auditory stimuli and may be specific to a dance style and the music accompanying it. PMID:25301352

  7. The mode of synaptic activation of pyramidal neurons in the cat primary somatosensory cortex: an intracellular HRP study.

    Science.gov (United States)

    Yamamoto, T; Samejima, A; Oka, H

    1990-01-01

    A total of 141 pyramidal neurons in the cat primary somatosensory cortex (SI) were recorded intracellularly under Nembutal anesthesia (7 in layer II, 43 in layer III, 8 in layer IV, 58 in layer V and 25 in layer VI). Most neurons were identified by intracellular staining with HRP, though some layer V pyramidal neurons were identified only electrophysiologically with antidromic activation of medullary pyramid (PT) or pontine nuclear (PN) stimulation. Excitatory synaptic potentials (EPSPs) were analyzed with stimulation of the superficial radial nerve (SR), the ventral posterolateral nucleus (VPL) in the thalamus and the thalamic radiation (WM). The pyramidal neurons in layers III and IV received EPSPs at the shortest latency: 9.1 +/- 2.1 ms (Mean +/- S.D.) for SR and 1.6 +/- 0.7 ms for VPL stimulation. Layer II pyramidal neurons also responded at a short latency to VPL stimulation (1.7 +/- 0.5 ms), though their mean latencies for SR-induced EPSPs were relatively longer (10.6 +/- 1.9 ms). The mean latencies were much longer in layers V and VI pyramidal neurons (10.2 +/- 2.4 ms and 2.9 +/- 1.5 ms in layer V pyramidal neurons and 9.9 +/- 2.5 ms and 2.8 +/- 1.6 ms in layer VI pyramidal ones, respectively for SR and VPL stimulation). The comparison of the latencies between VPL and WM stimulation indicates that most layer III-IV pyramidal neurons and some pyramidal cells in layers II, V and VI received monosynaptic inputs from VPL. These findings are consistent with morphological data on the laminar distribution of thalamocortical fibers, i.e., thalamocortical fibers terminate mainly in the deeper part of layers III and IV with some collaterals in layers V, VI and II-I. The time-sequences of the latencies of VPL-EPSPs indicate that corticocortical and/or transcallosal neurons (pyramidal neurons in layers II and III) fire first and are followed by firing of the output neurons projecting to the subcortical structures (pyramidal neurons in layers V and VI). PMID:2358022

  8. Differential effects of prenatal chronic high-decibel noise and music exposure on the excitatory and inhibitory synaptic components of the auditory cortex analog in developing chicks (Gallus gallus domesticus).

    Science.gov (United States)

    Kumar, V; Nag, T C; Sharma, U; Jagannathan, N R; Wadhwa, S

    2014-06-01

    Proper development of the auditory cortex depends on early acoustic experience that modulates the balance between excitatory and inhibitory (E/I) circuits. In the present social and occupational environment exposure to chronic loud sound in the form of occupational or recreational noise, is becoming inevitable. This could especially disrupt the functional auditory cortex development leading to altered processing of complex sound and hearing impairment. Here we report the effects of prenatal chronic loud sound (110-dB sound pressure level (SPL)) exposure (rhythmic [music] and arrhythmic [noise] forms) on the molecular components involved in regulation of the E/I balance in the developing auditory cortex analog/Field L (AuL) in domestic chicks. Noise exposure at 110-dB SPL significantly enhanced the E/I ratio (increased expression of AMPA receptor GluR2 subunit and glutamate with decreased expression of GABA(A) receptor gamma 2 subunit and GABA), whereas loud music exposure maintained the E/I ratio. Expressions of markers of synaptogenesis, synaptic stability and plasticity i.e., synaptophysin, PSD-95 and gephyrin were reduced with noise but increased with music exposure. Thus our results showed differential effects of prenatal chronic loud noise and music exposures on the E/I balance and synaptic function and stability in the developing auditory cortex. Loud music exposure showed an overall enrichment effect whereas loud noise-induced significant alterations in E/I balance could later impact the auditory function and associated cognitive behavior. PMID:24721732

  9. Characterizing spatial tuning functions of neurons in the auditory cortex of young and aged monkeys: A new perspective on old data.

    Directory of Open Access Journals (Sweden)

    James eEngle

    2013-01-01

    Full Text Available Age-related hearing deficits are a leading cause of disability among the aged. While some forms of hearing deficits are peripheral in origin, others are centrally mediated. One such deficit is the ability to localize sounds, a critical component for segregating different acoustic objects and events, which is dependent on the auditory cortex. Recent evidence indicates that in aged animals the normal sharpening of spatial tuning between neurons in primary auditory cortex to the caudal lateral field does not occur as it does in younger animals. As a decrease in inhibition with aging is common in the ascending auditory system, it is possible that this lack of spatial tuning sharpening is due to a decrease in inhibition at different periods within the response. It is also possible that spatial tuning was decreased as a consequence of reduced inhibition at non-best locations. In this report we found that aged animals did have greater activity throughout the response period, but primarily during the onset of the response. This was most prominent at non-best directions, consistent with the hypothesis that inhibition is a primary mechanism to sharpen spatial tuning curves. We also noted that in aged animals the latency of the response was much shorter than in younger animals, consistent with a decrease in pre-onset inhibition. These results can be interpreted in the context of a failure of the timing and efficiency of feed-forward thalamo-cortical and cortico-cortical circuits in aged animals. Such a mechanism, if generalized across cortical areas, could play a major role in age-related cognitive decline.

  10. Alcohol abuse and HIV infection have additive effects on frontal cortex function as measured by auditory evoked potential P3A latency.

    Science.gov (United States)

    Fein, G; Biggins, C A; MacKay, S

    1995-02-01

    Both alcohol and human immunodeficiency virus (HIV) infection have been shown to produce central nervous system (CNS) morbidity in frontal brain regions. The degree to which the CNS morbidity in HIV infection, as it affects frontal cortex function, may be preferentially increased by alcohol abuse was examined using the auditory P3A evoked potential. The P3A indexes an orienting response, maximal over frontal cortex that occurs when novel nontarget stimuli are presented in the midst of a target detection paradigm. Four groups of subjects were compared: HIV+ alcohol abusers, HIV+ light/nondrinkers, HIV- alcohol abusers, and HIV- light/nondrinkers. The alcohol abuser and light/nondrinker HIV+ groups were matched on percent CD4 lymphocytes, insuring that the results reflected specific CNS effects and were not a result of differences between the groups in the degree of systemic immune suppression. Alcohol abuse and HIV infection had at least additive effects on P3A latency, consistent with alcohol abuse worsening the effect of HIV disease on frontal cortex function. Post-hoc analyses suggested that concomitant alcohol abuse results in the effects of HIV infection on P3A latency becoming manifest earlier in the HIV disease process. PMID:7727627

  11. 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...

  12. Early Cross-Modal Interactions in Auditory and Visual Cortex Underlie a Sound-Induced Visual Illusion

    OpenAIRE

    Mishra, Jyoti; Martinez, Antigona; Sejnowski, Terrence J.; Hillyard, Steven A.

    2007-01-01

    When a single flash of light is presented interposed between two brief auditory stimuli separated by 60 –100 ms, subjects typically report perceiving two flashes (Shams et al., 2000, 2002). We investigated the timing and localization of the cortical processes that underlie this illusory flash effect in 34 subjects by means of 64-channel recordings of event-related potentials (ERPs). A difference ERP calculated to isolate neural activity associated with the illusory second flash revealed an ea...

  13. The GABAA receptor α and β subunits but not the density of muscimol binding sites are altered in the auditory-linguistic association cortex of subjects with schizophrenia

    International Nuclear Information System (INIS)

    Full text: An increase in the density of postsynaptic GABAA receptors has recently been reported in the prefrontal cortex of subjects with schizophrenia. This increase has been hypothesised to represent an up-regulation in response a decrease in the density of GABAergic interneurons. In order to determine whether the GABAA receptor is also altered in the auditory-linguistic association cortex of the schizophrenic brain, we used quantitative autoradiography to measure the density of that receptor in tissue obtained at autopsy from 20 control subjects and 20 subjects with schizophrenia matched for sex and age. The density of GABAA receptors was measured as the difference in the binding of the specific ligand [3H]muscimol (100 nM) in the presence or in the absence of 105 M SR95531. There was no significant difference in the density of [3H]muscimol binding between tissue from schizophrenic (554.9±20,5 fmol/mg TE) and non-schizophrenic (580.1±26.2 fmol/mg TE) subjects. The abundance of the α and β subunits of the GABAA receptor was also measured in particulate membranes prepared from tissue from 6 control and 6 schizophrenic subjects using Western blots. Detection with monoclonal antibodies and chemiluminescence showed that in tissue from control subjects, there was a significant correlation between the levels of α and β subunits (r=0.817, p=0.047). However, there was no such correlation in tissue from schizophrenic subjects (r=0.265, p=0.61), where in 2 subjects large levels of β-subunit were not matched by similar levels of α subunit. These preliminary results suggest mat there may be a failure for up-regulated GABAA receptor subunits to assemble into functional receptors in this brain region for some subjects with schizophrenia. Copyright (1998) Australian Neuroscience Society

  14. 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...

  15. A realistic neural mass model of the cortex with laminar-specific connections and synaptic plasticity - evaluation with auditory habituation.

    Directory of Open Access Journals (Sweden)

    Peng Wang

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

  16. The study of diffusion weighted imaging and MR spectroscopy in auditory cortex and related area of prelingual hearing-loss patients

    International Nuclear Information System (INIS)

    Objective: To study the time-dependent changes and mechanisms of auditory cortex in prelingual sensorineural hearing loss. Methods: Two groups (9-12, 19-22-year-old) of heating-loss patients and matched normal hearing subjects received MR diffusion and MRS examination. The ROI for ADC measurement were placed on the Heschl gyms (HG), and for NAA/Cr, Cho/Cr on the superior temporal gyrus(STG). Results: There was no statistical difference among groups both in the NAA/Cr and Cho/Cr (P>0.05), Left side NAA/Cr 2.46±0.51, 2.49±0.52, 2.26±0.33; Right side NAA/Cr 2.26±0.46, 2.44±0.45, 2.27±0.46. Left side Cho/Cr 0.88±0.21, 0.92±0.18, 0.87±0.13; Right side Cho/Cr 0.88±0.18, 0.87±0.22, 0.81±0.16. There was statistical difference of ADC value among normal hearing subjects and 9-12, 19-22-year-old heating-loss patients (F=4.42, P2/s, Right side (848±73), (880±61), (902±52) mm2/s. Conclusion: Compared with the normal hearing, the ADC value increased in 20-year-length of deafness. The NAA/Cr and Cho/Cr of STG showed no changes among the three groups. (authors)

  17. 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 ...

  18. 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

  19. Resting-state functional connectivity MRI in observation on auditory cortex in normal hearing subjects%静息态功能磁共振成像观察正常人听觉皮层功能

    Institute of Scientific and Technical Information of China (English)

    李晶; 杨明; 刘斌; 张光玉; 杨小庆; 吴旻; 黄志纯; 季慧

    2012-01-01

    Objective To evaluate the positive and negative connectivity of auditory cortex with whole brain in normal subjects with functional connectivity MRI in resting state. Methods Functional connectivity MRI and echo-planar imaging sequence were employed in 44 normal subjects in resting state. Bilateral A I s were applied as ROIs, and the positive and negative correlation brain mappings were obtained between the primary auditory cortex and the whole brain, respectively. Results Each ROI was positively correlated with the bilateral AⅠ , AⅡ insula, supplementary motor area and gyri cingu-li, mainly in the ipsilateral areas. However, the right thalamus was also found to be positively correlated with the right A I . Negative correlation maps were found in the posterior cingulate cortex/precuneus, medial frontal cortex and bilateral inferior parietal lobule, which shared some resemblance to the default mode network. Bilateral A I s were also significantly negatively correlated with the cerebellum. Conclusion Functional connectivity brain maps of auditory cortex can be acquired satisfactorily using resting state functional MRL The positive functional connectivity is mainly limited in the auditory cortex, and negative correlation maps shares some resemblance to the default mode network.z%目的 探讨正常人听觉皮层与全脑的正相关及负相关的功能连接.方法 采用静息态下平面回波成像技术采集44名健康受试者fMRI数据,分别以左侧及右侧AⅠ区为种子点,用功能连接的方法观察左、右大脑初级听觉皮层与全脑的正相关及负相关功能连接脑图.结果 分别以双侧AⅠ区为种子点时,正激活的脑网络主要包含双侧AⅠ、AⅡ、岛叶、辅助运动区及扣带回,以同侧为主;与右侧AⅠ区相关的正激活脑区还包括同侧背侧丘脑.与双侧AⅠ区相关的负激活脑网络与脑默认网络大体一致,主要包括双侧后扣带回/楔前叶、额叶内侧回、顶下小叶,

  20. 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.

  1. 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

  2. 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 ...

  3. 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...

  4. Extinction, applied after retrieval of auditory fear memory, selectively increases zinc-finger protein 268 and phosphorylated ribosomal protein S6 expression in prefrontal cortex and lateral amygdala.

    Science.gov (United States)

    Tedesco, Vincenzo; Roquet, Rheall F; DeMis, John; Chiamulera, Cristiano; Monfils, Marie-H

    2014-11-01

    Retrieval of consolidated memories induces a labile phase during which memory can be disrupted or updated through a reconsolidation process. A central component of behavioral updating during reconsolidation using a retrieval-extinction manipulation (Ret+Ext) is the synaptic removal of a calcium-permeable-α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (CP-AMPARs) in the lateral amygdala-a metabotropic GluR1 receptor (mGluR1) dependent mechanism. In the present study, we investigate the effect of Ret+Ext on the expression of molecular markers that could play a role in the reconsolidation process. Specifically, we tested the effects of Ret+Ext on the global expression of zinc-finger 268 protein (Zif268), a marker previously found to be implicated in memory reconsolidation, to confirm its occurrence after retrieval (Ret) and Ret+Ext. We also evaluated the global expression of phosphorylated ribosomal protein S6 (rpS6P), here proposed as a marker of the mGluR1-mediated memory process induced by Ret+Ext. The expression of both markers (zif268, rpS6P) was assessed by immunolocalization in prelimbic cortex (PRL), infralimbic cortex (IL), ventral subdivision of the lateral amygdala (LA) and hippocampus CA1 (CA1) in fear-conditioned rats. Our results showed that retrieval and Ret+Ext, but not extinction alone, increased Zif268 expression in prefrontal cortex and lateral amygdala. Ret+Ext, but not retrieval, retrieval followed by context exposure or extinction alone, increased the expression of rpS6P in prefrontal cortex and LA. In summary, (i) Zif268 increased after retrieval confirming that reconsolidation is engaged in our conditions, (ii) Zif268 increased after Ret+Ext confirming that it does not simply reflect an extinction or reconsolidation disruption (Zif268 level of expression should be lower in both cases) and (iii) rpS6P increased after Ret+Ext, but not after extinction, suggesting, as expected, a potential mGluR1 mediated molecular mechanism specific

  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. Voxel based statistical analysis method for microPET studies to assess the cerebral glucose metabolism in cat deafness model: comparison to ROI based method

    International Nuclear Information System (INIS)

    Imaging research on the brain of sensory-deprived cats using small animal PET scanner has gained interest since the abundant information about the sensory system of ths animal is available and close examination of the brain is possible due to larger size of its brain than mouse or rat. In this study, we have established the procedures for 3D voxel-based statistical analysis (SPM) of FDG PET image of cat brain, and confirmed using ROI based-method. FDG PET scans of 4 normal and 4 deaf cats were acquired for 30 minutes using microPET R4 scanner. Only the brain cortices were extracted using a masking and threshold method to facilitate spatial normalization. After spatial normalization and smoothing, 3D voxel-wise and ROI based t-test were performed to identify the regions with significant different FDG uptake between the normal and deaf cats. In ROI analysis, 26 ROIs were drawn on both hemispheres, and regional mean pixel value in each ROI was normalized to the global mean of the brain. Cat brains were spatially normalized well onto the target brain due to the removal of background activity. When cerebral glucose metabolism of deaf cats were compared to the normal controls after removing the effects of the global count, the glucose metabolism in the auditory cortex, head of caudate nucleus, and thalamus in both hemispheres of the deaf cats was significantly lower than that of the controls (P<0.01). No area showed a significantly increased metabolism in the deaf cats even in higher significance level (P<0.05). ROI analysis also showed significant reduction of glucose metabolism in the same region. This study established and confirmed a method for voxel-based analysis of animal PET data of cat brain, which showed high localization accuracy and specificity and was useful for examining the cerebral glucose metabolism in a cat cortical deafness model

  7. Voxel based statistical analysis method for microPET studies to assess the cerebral glucose metabolism in cat deafness model: comparison to ROI based method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Su; Lee, Jae Sung; Park, Min Hyun; Lee, Jong Jin; Kang, Hye Jin; Lee, Hyo Jeong; Oh, Seung Ha; Kim, Chong Sun; Jung, June Key; Lee, Myung Chul; Lee, Dong Soo [Seoul National University College of Medicine, Seoul (Korea, Republic of); Lim, Sang Moo [KIRAMS, Seoul (Korea, Republic of)

    2005-07-01

    Imaging research on the brain of sensory-deprived cats using small animal PET scanner has gained interest since the abundant information about the sensory system of ths animal is available and close examination of the brain is possible due to larger size of its brain than mouse or rat. In this study, we have established the procedures for 3D voxel-based statistical analysis (SPM) of FDG PET image of cat brain, and confirmed using ROI based-method. FDG PET scans of 4 normal and 4 deaf cats were acquired for 30 minutes using microPET R4 scanner. Only the brain cortices were extracted using a masking and threshold method to facilitate spatial normalization. After spatial normalization and smoothing, 3D voxel-wise and ROI based t-test were performed to identify the regions with significant different FDG uptake between the normal and deaf cats. In ROI analysis, 26 ROIs were drawn on both hemispheres, and regional mean pixel value in each ROI was normalized to the global mean of the brain. Cat brains were spatially normalized well onto the target brain due to the removal of background activity. When cerebral glucose metabolism of deaf cats were compared to the normal controls after removing the effects of the global count, the glucose metabolism in the auditory cortex, head of caudate nucleus, and thalamus in both hemispheres of the deaf cats was significantly lower than that of the controls (P<0.01). No area showed a significantly increased metabolism in the deaf cats even in higher significance level (P<0.05). ROI analysis also showed significant reduction of glucose metabolism in the same region. This study established and confirmed a method for voxel-based analysis of animal PET data of cat brain, which showed high localization accuracy and specificity and was useful for examining the cerebral glucose metabolism in a cat cortical deafness model.

  8. Dramatic loss of Ube3A expression during aging of the mammalian cortex

    Directory of Open Access Journals (Sweden)

    Kathryn M Murphy

    2010-05-01

    Full Text Available Neurobiological studies of aging are beginning to link functional changes with a loss of experience-dependent plasticity. In the visual system, age-related functional changes include decreases in visual acuity, orientation selectivity, motion perception, and ocular dominance plasticity. A recent paper has shown that Ube3A, an E3 ubiquitin ligase that is absent in Angelman's Syndrome, is required for experience-dependent plasticity during development of the visual cortex. Knocking out Ube3A during development leads to rigidity of ocular dominance plasticity that is strikingly similar to the reduced plasticity seen in older animals. Furthermore, ubiquitin ligases have been linked with age-related neurodegenerative disorders and longevity. Ubiquitin ligases selectively mark proteins for degradation, and a balance between synaptic proteins and their degradation is important for neural transmission and plasticity. This led us to ask whether normal aging is characterized by a loss of Ube3A in the cortex. We used Western blot analysis in order to quantify Ube3A expression across the life span of humans, macaque monkeys, and cats. We found that Ube3A expression declines across the lifespan in human, monkey, and cat cortex. The losses were substantial (50-80% in all areas studied which includes V1, V3, V4, frontal, and auditory cortex. In addition, when compared with other synaptic proteins there was a selective loss of Ube3A in human cortex. The progressive loss of Ube3A expression during cortical aging is an important new finding. Furthermore, the selective loss of Ube3A in human cortex highlights a specific vulnerability in human brain aging that may signify a dramatic shift in cortical function and plasticity.

  9. 小鼠初级听皮质神经元的强度调谐特性与机制分析%Intensity Tuning of Neurons in The Primary Auditory Cortex of Albino Mouse

    Institute of Scientific and Technical Information of China (English)

    齐巧珍; 佀文娟; 罗峰; 王欣

    2013-01-01

    强度是声音的基本参数之一,听神经元的强度调谐在听觉信息处理方面具有重要意义.以往研究发现γ-氨基丁酸(γ-aminobutyric acid,GABA)能抑制性输入在强度调谐的形成过程中起重要作用,但对抑制性输入与局部神经回路之间的关系并不清楚.本实验通过在体细胞外电生理记录和神经药理学方法,分析了小鼠初级听皮质神经元的强度调谐特性,结果显示:单调型神经元在声刺激强度自中等强度增高时潜伏期缩短(P<0.05)且发放持续时间延长(P<0.05),非单调型神经元在声刺激强度自最佳强度增高时潜伏期不变且发放持续时间缩短(P<0.01).注射GABA能阻断剂荷包牡丹碱(bicuculline,Bic)后,39.3%的神经元强度调谐类型不变,42.9%的神经元非单调性减弱,17.9%的神经元非单调性增强.表明GABA能抑制并非是形成非单调性的唯一因素,兴奋性输入本身的非单调性和高阈值非GABA能抑制的激活也可能在其中发挥作用.推测由兴奋性和抑制性输入所构成的局部神经功能回路及其整合决定了听皮质神经元的强度调谐特性.%Cortical neurons that are tuned to sound intensity (non-monotonic neurons) are very important for processing auditory information. Considering the fact that all auditory nerve fibers have monotonical responses, inhibition in the primary auditory cortex (AI) is essential for intensity tuning. By using free field sound stimulation and in vivo extracellular recording, the present study investigated the intensity-tuning properties in AI neurons of mouse (Mus musculus, Km). We also examined the effect of cortical application of the GABAa receptor antagonist bicuculline on AI intensity tuning in order to indentify the possible source of inhibition. The intensity-tuning curves were recorded in 72 AI neurons among which 28 showed monotonic responses and 44 showed non-monotonic responses. In non-monotonic neurons, there was no

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

    DEFF Research Database (Denmark)

    Parving, A; Salomon, G; Elberling, Claus;

    1980-01-01

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

  11. 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.

  12. 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 ...

  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. Cat Scan

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> A man takes his motionless dog to the vet."Doc,I think my dog is dead.”The vet looks the dog over, goes into a backroom,and comes out with a cat.He places the caton the table next to the dog.The cat walks aroundand sniffs at the dog.The dog does not move.The

  16. 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

  17. Fundamental deficits of auditory perception in Wernicke’s aphasia

    OpenAIRE

    Robson, Holly; Grube, Manon; Lambon Ralph, Matthew; Griffiths, Timothy; Sage, Karen

    2012-01-01

    Objective: This work investigates the nature of the comprehension impairment in Wernicke’s aphasia, by examining the relationship between deficits in auditory processing of fundamental, non-verbal acoustic stimuli and auditory comprehension. Wernicke’s aphasia, a condition resulting in severely disrupted auditory comprehension, primarily occurs following a cerebrovascular accident (CVA) to the left temporo-parietal cortex. Whilst damage to posterior superior temporal areas is associated wit...

  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. Cat scratch disease (image)

    Science.gov (United States)

    Cat scratch disease is an infectious illness associated with cat scratches, bites, or exposure to cat saliva, causing chronic swelling of the lymph nodes. Cat scratch disease is possibly the most common cause of ...

  20. Cat's Claw

    Science.gov (United States)

    ... R S T U V W X Y Z Cat's Claw Share: On This Page Introduction What the ... More Information Key References © Steven Foster Common Names: cat’s claw, uña de gato Latin Name: Uncaria tomentosa, ...

  1. A quantitative comparison of the hemispheric, areal, and laminar origins of sensory and motor cortical projections to the superior colliculus of the cat.

    Science.gov (United States)

    Butler, Blake E; Chabot, Nicole; Lomber, Stephen G

    2016-09-01

    The superior colliculus (SC) is a midbrain structure central to orienting behaviors. The organization of descending projections from sensory cortices to the SC has garnered much attention; however, rarely have projections from multiple modalities been quantified and contrasted, allowing for meaningful conclusions within a single species. Here, we examine corticotectal projections from visual, auditory, somatosensory, motor, and limbic cortices via retrograde pathway tracers injected throughout the superficial and deep layers of the cat SC. As anticipated, the majority of cortical inputs to the SC originate in the visual cortex. In fact, each field implicated in visual orienting behavior makes a substantial projection. Conversely, only one area of the auditory orienting system, the auditory field of the anterior ectosylvian sulcus (fAES), and no area involved in somatosensory orienting, shows significant corticotectal inputs. Although small relative to visual inputs, the projection from the fAES is of particular interest, as it represents the only bilateral cortical input to the SC. This detailed, quantitative study allows for comparison across modalities in an animal that serves as a useful model for both auditory and visual perception. Moreover, the differences in patterns of corticotectal projections between modalities inform the ways in which orienting systems are modulated by cortical feedback. J. Comp. Neurol. 524:2623-2642, 2016. © 2016 Wiley Periodicals, Inc. PMID:26850989

  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 Catalogue of Anatomical Fugitive Sheets: Cat. 49-62

    OpenAIRE

    1999-01-01

    Images Cat. 50 Cat. 51 Cat. 53 Cat. 54 Cat. 55 (a) Cat. 55 (b) Cat. 56 Cat. 57: 1 Cat. 57: 2 Cat. 57: 3 Cat. 57: 4 Cat. 59: 1 Cat. 59: 2 Cat. 59: 3 Cat. 59: 4 Cat. 60 Cat. 61 Cat. 62: 1 (a) Cat. 62: 1 (b) Cat. 62: 2 (a) Cat. 62: 2 (b)

  4. A Catalogue of Anatomical Fugitive Sheets: Cat. 26-48

    OpenAIRE

    1999-01-01

    Images Cat. 26: 1 (a) Cat. 26: 1 (b) Cat. 26: 2 (a) Cat. 26: 2(b) Cat. 27: 1 (a) Cat. 27: 1 (b) Cat. 27: 2 (a) Cat. 27: 2 (b) Cat. 28 Cat. 29: 2 (a) Cat. 29: 2 (b) Cat. 30: 1 Cat. 30: 2 Cat. 30: 3 Cat. 33 Cat. 34: 1 Cat. 34: 2 Cat. 35: 1 Cat. 35: 2 Cat. 35: 3 Cat. 36 Cat. 37 Cat. 38: 1 Cat. 38: 2 Cat. 40 Cat. 42 Cat. 43 Cat. 44 Cat. 45: 1 Cat. 45: 2 Cat. 46 Cat. 47: 1 Cat. 47: 2 Cat. 47: 3 Cat. 48: 1 Cat. 48: 2 Cat. 48: 3

  5. 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

  6. 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

  7. Specialized prefrontal “auditory fields”: organization of primate prefrontal-temporal pathways

    Directory of Open Access Journals (Sweden)

    MariaMedalla

    2014-04-01

    Full Text Available No other modality is more frequently represented in the prefrontal cortex than the auditory, but the role of auditory information in prefrontal functions is not well understood. Pathways from auditory association cortices reach distinct sites in the lateral, orbital, and medial surfaces of the prefrontal cortex in rhesus monkeys. Among prefrontal areas, frontopolar area 10 has the densest interconnections with auditory association areas, spanning a large antero-posterior extent of the superior temporal gyrus from the temporal pole to auditory parabelt and belt regions. Moreover, auditory pathways make up the largest component of the extrinsic connections of area 10, suggesting a special relationship with the auditory modality. Here we review anatomic evidence showing that frontopolar area 10 is indeed the main frontal “auditory field” as the major recipient of auditory input in the frontal lobe and chief source of output to auditory cortices. Area 10 is thought to be the functional node for the most complex cognitive tasks of multitasking and keeping track of information for future decisions. These patterns suggest that the auditory association links of area 10 are critical for complex cognition. The first part of this review focuses on the organization of prefrontal-auditory pathways at the level of the system and the synapse, with a particular emphasis on area 10. Then we explore ideas on how the elusive role of area 10 in complex cognition may be related to the specialized relationship with auditory association cortices.

  8. Central auditory development in children with cochlear implants: clinical implications.

    Science.gov (United States)

    Sharma, Anu; Dorman, Michael F

    2006-01-01

    A common finding in developmental neurobiology is that stimulation must be delivered to a sensory system within a narrow window of time (a sensitive period) during development in order for that sensory system to develop normally. Experiments with congenitally deaf children have allowed us to establish the existence and time limits of a sensitive period for the development of central auditory pathways in humans. Using the latency of cortical auditory evoked potentials (CAEPs) as a measure we have found that central auditory pathways are maximally plastic for a period of about 3.5 years. If the stimulation is delivered within that period CAEP latencies reach age-normal values within 3-6 months after stimulation. However, if stimulation is withheld for more than 7 years, CAEP latencies decrease significantly over a period of approximately 1 month following the onset of stimulation. They then remain constant or change very slowly over months or years. The lack of development of the central auditory system in congenitally deaf children implanted after 7 years is correlated with relatively poor development of speech and language skills [Geers, this vol, pp 50-65]. Animal models suggest that the primary auditory cortex may be functionally decoupled from higher order auditory cortex due to restricted development of inter- and intracortical connections in late-implanted children [Kral and Tillein, this vol, pp 89-108]. Another aspect of plasticity that works against late-implanted children is the reorganization of higher order cortex by other sensory modalities (e.g. vision). The hypothesis of decoupling of primary auditory cortex from higher order auditory cortex in children deprived of sound for a long time may explain the speech perception and oral language learning difficulties of children who receive an implant after the end of the sensitive period. PMID:16891837

  9. 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

  10. Effects of the Bee Venom Herbal Acupuncture on the Neurotransmitters of the Rat Brain Cortex

    Directory of Open Access Journals (Sweden)

    Hyoung-Seok Yun

    2001-02-01

    Full Text Available In order to study the effects of bee venom Herbal Acupuncture on neurotransmitters in the rat brain cortex, herbal acupuncture with bee venom group and normal saline group was performed at LI4 bilaterally of the rat. the average optical density of neurotransmitters from the cerebral cortex was analysed 30 minutes after the herbal aqupuncture, by the immunohistochemistry. The results were as follows: 1. The density of NADPH-diaphorase in bee venom group was increased significantly at the motor cortex, visual cortex, auditory cortex, cingulate cortex, retrosplenial cortex and perirhinal cortex compared to the normal saline group. 2. The average optical density of vasoactive intestinal peptide in bee venom group had significant changes at the insular cortex, retrosplenial cortex and perirhinal cortex, compared to the normal saline group. 3. The average optical density of neuropeptide-Y in bee venom group increased significantly at the visual cortex and cingulate cortex, compared to the normal saline group.

  11. The auditory and non-auditory brain areas involved in tinnitus. An emergent property of multiple parallel overlapping subnetworks.

    Science.gov (United States)

    Vanneste, Sven; De Ridder, Dirk

    2012-01-01

    Tinnitus is the perception of a sound in the absence of an external sound source. It is characterized by sensory components such as the perceived loudness, the lateralization, the tinnitus type (pure tone, noise-like) and associated emotional components, such as distress and mood changes. Source localization of quantitative electroencephalography (qEEG) data demonstrate the involvement of auditory brain areas as well as several non-auditory brain areas such as the anterior cingulate cortex (dorsal and subgenual), auditory cortex (primary and secondary), dorsal lateral prefrontal cortex, insula, supplementary motor area, orbitofrontal cortex (including the inferior frontal gyrus), parahippocampus, posterior cingulate cortex and the precuneus, in different aspects of tinnitus. Explaining these non-auditory brain areas as constituents of separable subnetworks, each reflecting a specific aspect of the tinnitus percept increases the explanatory power of the non-auditory brain areas involvement in tinnitus. Thus, the unified percept of tinnitus can be considered an emergent property of multiple parallel dynamically changing and partially overlapping subnetworks, each with a specific spontaneous oscillatory pattern and functional connectivity signature. PMID:22586375

  12. The auditory and non-auditory brain areas involved in tinnitus. An emergent property of multiple parallel overlapping subnetworks.

    Directory of Open Access Journals (Sweden)

    Sven Vanneste

    2012-05-01

    Full Text Available Tinnitus is the perception of a sound in the absence of an external sound source. It is characterized by sensory components such as the perceived loudness, the lateralization, the tinnitus type (pure tone, noise-like and associated emotional components, such as distress and mood changes. Source localization of qEEG data demonstrate the involvement of auditory brain areas as well as several non-auditory brain areas such as the anterior cingulate cortex (dorsal and subgenual, auditory cortex (primary and secondary, dorsal lateral prefrontal cortex, insula, supplementary motor area, orbitofrontal cortex (including the inferior frontal gyrus, parahippocampus, posterior cingulate cortex and the precuneus, in different aspects of tinnitus. Explaining these non-auditory brain areas as constituents of separable subnetworks, each reflecting a specific aspect of the tinnitus percept increases the explanatory power of the non-auditory brain areas involvement in tinnitus. Thus the unified percept of tinnitus can be considered an emergent property of multiple parallel dynamically changing and partially overlapping subnetworks, each with a specific spontaneous oscillatory pattern and functional connectivity signature.

  13. Prefrontal activity predicts monkeys' decisions during an auditory category task

    Directory of Open Access Journals (Sweden)

    Jung Hoon Lee

    2009-06-01

    Full Text Available The neural correlates that relate auditory categorization to aspects of goal-directed behavior, such as decision-making, are not well understood. Since the prefrontal cortex plays an important role in executive function and the categorization of auditory objects, we hypothesized that neural activity in the prefrontal cortex (PFC should predict an animal's behavioral reports (decisions during a category task. To test this hypothesis, we tested PFC activity that was recorded while monkeys categorized human spoken words (Russ et al., 2008b. We found that activity in the ventrolateral PFC, on average, correlated best with the monkeys' choices than with the auditory stimuli. This finding demonstrates a direct link between PFC activity and behavioral choices during a non-spatial auditory task.

  14. Schroedinger's cat

    International Nuclear Information System (INIS)

    The issue is to seek quantum interference effects in an arbitrary field, in particular in psychology. For this a digest of quantum mechanics over finite-n-dimensional Hilbert space is invented. In order to match crude data not only von Neumann's mixed states are used but also a parallel notion of unsharp tests. The mathematically styled text (and earlier work on multibin tests, designated MB) deals largely with these new tests. Quantum psychology itself is only given a foundation. It readily engenders objections; its plausibility is developed gradually, in interlocking essays. There is also the empirically definite proposal that (state, test, outcome)-indexed counts be gathered to record data, then fed to a 'matrix format' (MF) search for quantum models. A previously proposed experiment in visual perception which has since failed to find significant quantum correlations, is discussed. The suspicion that quantum mechanics is all around goes beyond MF, and 'Schroedinger's cat' symbolizes this broader perspective. (author)

  15. FUNCTIONAL AND STRUCTURAL CHANGES THROUGHOUT THE AUDITORY SYSTEM FOLLOWING CONGENITAL AND EARLY-ONSET DEAFNESS: IMPLICATIONS FOR HEARING RESTORATION

    OpenAIRE

    Lomber, Stephen G.

    2013-01-01

    The absence of auditory input, particularly during development, causes widespread changes in the structure and function of the auditory system, extending from peripheral structures into auditory cortex. In humans, the consequences of these changes are far-reaching and often include detriments to language acquisition, and associated psychosocial issues. Much of what is currently known about the nature of deafness-related changes to auditory structures comes from studies of congenitally deaf ...

  16. Functional and structural changes throughout the auditory system following congenital and early-onset deafness: implications for hearing restoration

    OpenAIRE

    Butler, Blake E.; Lomber, Stephen G.

    2013-01-01

    The absence of auditory input, particularly during development, causes widespread changes in the structure and function of the auditory system, extending from peripheral structures into auditory cortex. In humans, the consequences of these changes are far-reaching and often include detriments to language acquisition, and associated psychosocial issues. Much of what is currently known about the nature of deafness-related changes to auditory structures comes from studies of congenitally deaf or...

  17. Postnatal development of synaptic properties of the GABAergic projection from the inferior colliculus to the auditory thalamus

    OpenAIRE

    Venkataraman, Yamini; Bartlett, Edward L.

    2013-01-01

    The development of auditory temporal processing is important for processing complex sounds as well as for acquiring reading and language skills. Neuronal properties and sound processing change dramatically in auditory cortex neurons after the onset of hearing. However, the development of the auditory thalamus or medial geniculate body (MGB) has not been well studied over this critical time window. Since synaptic inhibition has been shown to be crucial for auditory temporal processing, this st...

  18. The Effects of Auditory Contrast Tuning upon Speech Intelligibility

    Science.gov (United States)

    Killian, Nathan J.; Watkins, Paul V.; Davidson, Lisa S.; Barbour, Dennis L.

    2016-01-01

    We have previously identified neurons tuned to spectral contrast of wideband sounds in auditory cortex of awake marmoset monkeys. Because additive noise alters the spectral contrast of speech, contrast-tuned neurons, if present in human auditory cortex, may aid in extracting speech from noise. Given that this cortical function may be underdeveloped in individuals with sensorineural hearing loss, incorporating biologically-inspired algorithms into external signal processing devices could provide speech enhancement benefits to cochlear implantees. In this study we first constructed a computational signal processing algorithm to mimic auditory cortex contrast tuning. We then manipulated the shape of contrast channels and evaluated the intelligibility of reconstructed noisy speech using a metric to predict cochlear implant user perception. Candidate speech enhancement strategies were then tested in cochlear implantees with a hearing-in-noise test. Accentuation of intermediate contrast values or all contrast values improved computed intelligibility. Cochlear implant subjects showed significant improvement in noisy speech intelligibility with a contrast shaping procedure.

  19. 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.

  20. 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.

  1. Cat and Dog Bites

    Science.gov (United States)

    MENU Return to Web version Cat and Dog Bites Cat and Dog Bites How should I take care of a bite from a cat or a dog? Whether from a family pet or a neighborhood stray, cat and dog bites are common. Here are some things you ...

  2. Activity changes of the cat paraventricular hypothalamus during stressor exposure

    DEFF Research Database (Denmark)

    Kristensen, Morten Pilgaard; Rector, David M; Poe, Gina R;

    2004-01-01

    Dorso-medial paraventricular hypothalamus (PVH) activity was assessed by light scattering procedures in freely behaving cats during auditory stressor exposure. Acoustic noise (> 95dB) raised plasma ACTH concentrations, somatic muscle tonus, respiratory frequency and cardiac rates; PVH activity...

  3. 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...

  4. Comparison of Auditory Evoked Potentials in Heterosexual, Homosexual, and Bisexual Males and Females

    OpenAIRE

    McFadden, Dennis; Champlin, Craig A.

    2000-01-01

    The auditory evoked potentials (AEPs) elicited by click stimuli were measured in heterosexual, homosexual, and bisexual males and females having normal hearing sensitivity. Estimates of latency and/or amplitude were extracted for nine peaks having latencies of about 2–240 ms, which are presumed to correspond to populations of neurons located from the auditory nerve through auditory cortex. For five of the 19 measures obtained, the mean latency or amplitude for the 57 homosexual and bisexual f...

  5. Incorporating Midbrain Adaptation to Mean Sound Level Improves Models of Auditory Cortical Processing

    OpenAIRE

    Harper, NS; Willmore, BDB; Schnupp, JWH; King, AJ; Schoppe, O

    2016-01-01

    Adaptation to stimulus statistics, such as the mean level and contrast of recently- heard sounds, has been demonstrated at various levels of the auditory pathway. It allows the nervous system to operate over the wide range of intensities and contrasts found in the natural world. Yet, current standard models of the response properties of auditory neurons do not incorporate such adaptation. Here, we present a model of neural responses in the ferret auditory cortex (the I...

  6. Diffusion tensor imaging of dolphin brains reveals direct auditory pathway to temporal lobe

    OpenAIRE

    Berns, Gregory S.; Cook, Peter F.; Foxley, Sean; Jbabdi, Saad; Miller, Karla L.; Marino, Lori

    2015-01-01

    The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes' auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this...

  7. Expression of cytoskeletal neurofilament protein in the somatosensory, visual and auditory cortices of rat

    Czech Academy of Sciences Publication Activity Database

    Druga, R.; Syka, Josef

    Geneva : Federation of European Neurosciences Societies, 2008. s. 188.8. [FENS. Forum of European Neuroscience /6./. 12.07.2008-16.07.2008, Geneva] R&D Projects: GA ČR GA309/07/1336; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390512 Keywords : Auditory * Auditory cortex Subject RIV: FH - Neurology

  8. 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

  9. Suppression of phase synchronisation in network based on cat's brain

    Science.gov (United States)

    Lameu, Ewandson L.; Borges, Fernando S.; Borges, Rafael R.; Iarosz, Kelly C.; Caldas, Iberê L.; Batista, Antonio M.; Viana, Ricardo L.; Kurths, Jürgen

    2016-04-01

    We have studied the effects of perturbations on the cat's cerebral cortex. According to the literature, this cortex structure can be described by a clustered network. This way, we construct a clustered network with the same number of areas as in the cat matrix, where each area is described as a sub-network with a small-world property. We focus on the suppression of neuronal phase synchronisation considering different kinds of perturbations. Among the various controlling interventions, we choose three methods: delayed feedback control, external time-periodic driving, and activation of selected neurons. We simulate these interventions to provide a procedure to suppress undesired and pathological abnormal rhythms that can be associated with many forms of synchronisation. In our simulations, we have verified that the efficiency of synchronisation suppression by delayed feedback control is higher than external time-periodic driving and activation of selected neurons of the cat's cerebral cortex with the same coupling strengths.

  10. Cat Scratch Disease

    Science.gov (United States)

    Cat scratch disease (CSD) is an illness caused by the bacterium Bartonella henselae. Almost half of all cats carry the infection ... symptoms of CSD, call your doctor. Centers for Disease Control and Prevention

  11. Cat Scratch Disease

    Science.gov (United States)

    Cat scratch disease (CSD) is an illness caused by the bacterium Bartonella henselae. Almost half of all cats carry the infection at some ... Poor appetite For people with weak immune systems, CSD may cause more serious problems. The best way ...

  12. 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

  13. Psychophysical and Neural Correlates of Auditory Attraction and Aversion

    Science.gov (United States)

    Patten, Kristopher Jakob

    This study explores the psychophysical and neural processes associated with the perception of sounds as either pleasant or aversive. The underlying psychophysical theory is based on auditory scene analysis, the process through which listeners parse auditory signals into individual acoustic sources. The first experiment tests and confirms that a self-rated pleasantness continuum reliably exists for 20 various stimuli (r = .48). In addition, the pleasantness continuum correlated with the physical acoustic characteristics of consonance/dissonance (r = .78), which can facilitate auditory parsing processes. The second experiment uses an fMRI block design to test blood oxygen level dependent (BOLD) changes elicited by a subset of 5 exemplar stimuli chosen from Experiment 1 that are evenly distributed over the pleasantness continuum. Specifically, it tests and confirms that the pleasantness continuum produces systematic changes in brain activity for unpleasant acoustic stimuli beyond what occurs with pleasant auditory stimuli. Results revealed that the combination of two positively and two negatively valenced experimental sounds compared to one neutral baseline control elicited BOLD increases in the primary auditory cortex, specifically the bilateral superior temporal gyrus, and left dorsomedial prefrontal cortex; the latter being consistent with a frontal decision-making process common in identification tasks. The negatively-valenced stimuli yielded additional BOLD increases in the left insula, which typically indicates processing of visceral emotions. The positively-valenced stimuli did not yield any significant BOLD activation, consistent with consonant, harmonic stimuli being the prototypical acoustic pattern of auditory objects that is optimal for auditory scene analysis. Both the psychophysical findings of Experiment 1 and the neural processing findings of Experiment 2 support that consonance is an important dimension of sound that is processed in a manner that aids

  14. 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

  15. Visual discrimination learning under switching procedure in visually deprived cats.

    Science.gov (United States)

    Zernicki, B

    1999-04-01

    Previous studies have shown that fine visual discrimination learning is severely impaired in cats binocularly deprived in the early period of life (BD cats) and also somewhat in control cats reared with open eyes in the limited laboratory environment (C cats) compared with cats reared in a normal rural environment (N cats). It was concluded that visual deprivation impairs perceptual learning. In the present study discriminative stimuli were dissimilar and so the task was perceptually easy, but using a switching procedure made it associatively difficult. In regular trials a gate with a grating pattern was positive and a blank gate negative, whereas in switching trials the meaning of the gates was reversed. The switching stimulus was intermittent light in some stages of training and intermittent tone in others. Learning was severely impaired in BD cats and somewhat in C cats and the deficit was similar under visual and auditory switching. Thus, early visual deprivation impairs associative learning. The impairment probably includes associations between switching stimulus and instrumental responses and configural associations between switching stimulus and discriminative stimuli. PMID:10212071

  16. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Snowboarding, Skating Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  17. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Here's Help White House Lunch Recipes Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  18. Discospondylitis in a cat

    International Nuclear Information System (INIS)

    The incidence and causative agents of discospondylitis in cats are unknown. This report describes a cat with radiologic changes consistent with discospondylitis and concurrent urinary tract infection. As in dogs, discospondylitis should be the primary rule out for vertebral end plate lysis in cats

  19. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that ...

  20. State- and trait-related alterations of motor cortex excitability in tinnitus patients

    OpenAIRE

    Schecklmann, Martin; Landgrebe, Michael; Kleinjung, Tobias; Frank, Elmar; Rupprecht, Rainer; Sand, Philipp G.; Eichhammer, Peter; Hajak, Göran; Langguth, Berthold

    2014-01-01

    Chronic tinnitus is a brain network disorder with involvement of auditory and non-auditory areas. Repetitive transcranial magnetic stimulation (rTMS) over the temporal cortex has been investigated for the treatment of tinnitus. Several small studies suggest that motor cortex excitability is altered in people with tinnitus. We retrospectively analysed data from 231 patients with chronic tinnitus and 120 healthy controls by pooling data from different studies. Variables of interest were resting...

  1. 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

  2. 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.

  3. 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.

  4. Pure word deafness with auditory object agnosia after bilateral lesion of the superior temporal sulcus.

    Science.gov (United States)

    Gutschalk, Alexander; Uppenkamp, Stefan; Riedel, Bernhard; Bartsch, Andreas; Brandt, Tobias; Vogt-Schaden, Marlies

    2015-12-01

    Based on results from functional imaging, cortex along the superior temporal sulcus (STS) has been suggested to subserve phoneme and pre-lexical speech perception. For vowel classification, both superior temporal plane (STP) and STS areas have been suggested relevant. Lesion of bilateral STS may conversely be expected to cause pure word deafness and possibly also impaired vowel classification. Here we studied a patient with bilateral STS lesions caused by ischemic strokes and relatively intact medial STPs to characterize the behavioral consequences of STS loss. The patient showed severe deficits in auditory speech perception, whereas his speech production was fluent and communication by written speech was grossly intact. Auditory-evoked fields in the STP were within normal limits on both sides, suggesting that major parts of the auditory cortex were functionally intact. Further studies showed that the patient had normal hearing thresholds and only mild disability in tests for telencephalic hearing disorder. Prominent deficits were discovered in an auditory-object classification task, where the patient performed four standard deviations below the control group. In marked contrast, performance in a vowel-classification task was intact. Auditory evoked fields showed enhanced responses for vowels compared to matched non-vowels within normal limits. Our results are consistent with the notion that cortex along STS is important for auditory speech perception, although it does not appear to be entirely speech specific. Formant analysis and single vowel classification, however, appear to be already implemented in auditory cortex on the STP. PMID:26343343

  5. Assessment of auditory cortical function in cochlear implant patients using 15O PET

    International Nuclear Information System (INIS)

    Full text: Cochlear implantation has been an extraordinarily successful method of restoring hearing and the potential for full language development in pre-lingually and post-lingually deaf individuals (Gibson 1996). Post-lingually deaf patients, who develop their hearing loss later in life, respond best to cochlear implantation within the first few years of their deafness, but are less responsive to implantation after several years of deafness (Gibson 1996). In pre-lingually deaf children, cochlear implantation is most effect in allowing the full development language skills when performed within a critical period, in the first 8 years of life. These clinical observations suggest considerable neural plasticity of the human auditory cortex in acquiring and retaining language skills (Gibson 1996, Buchwald 1990). Currently, electrocochleography is used to determine the integrity of the auditory pathways to the auditory cortex. However, the functional integrity of the auditory cortex cannot be determined by this method. We have defined the extent of activation of the auditory cortex and auditory association cortex in 6 normal controls and 6 cochlear implant patients using 15O PET functional brain imaging methods. Preliminary results have indicated the potential clinical utility of 15O PET cortical mapping in the pre-surgical assessment and post-surgical follow up of cochlear implant patients. Copyright (1998) Australian Neuroscience Society

  6. Adiponectin mRNA Expression in the Cat (Felis domesticus

    Directory of Open Access Journals (Sweden)

    Angela L. Lusby

    2010-01-01

    Full Text Available Problem statement: Adiponectin is a hormone expressed from adipose tissue in people, rodents and dogs. Adiponectin has anti-inflammatory action with beneficial effects on cardiovascular health and insulin sensitivity. With increasing fat mass, adiponectin concentrations paradoxically decrease. Adiponectin’s role in metabolism and diabetes mellitus is of interest in feline medicine because cats are susceptible to developing type II diabetes with weight gain. This study determined relative amounts of adiponectin mRNA expression from various body tissues and organs in domestic cats. Approach: Two intact male cats and one intact female cat were evaluated post-mortem. All cats were estimated to be young adults and had lean body conditions. Tissues samples from inguinal subcutaneous adipose, visceral mesenteric adipose, liver, skeletal muscle, cardiac muscle, aorta, stomach fundus, duodenum, pancreas, thyroid gland, adrenal gland (cortex and medulla and renal cortex were collected and frozen. Following RNA extraction, adiponectin mRNA expression of each tissue was detected using Reverse Transcriptase (RT real-time (Q PCR. Results: Visceral adipose tissue had the highest level of expression, averaging 12% higher than subcutaneous adipose. All other tissues had negligible levels of expression compared to adipose samples. Conclusion: This study provided a valuable step for adiponectin research in cats by determining which tissues express this hormone. Cats differ from human beings by expressing higher levels of adiponectin in visceral compared to subcutaneous fat. The metabolic impact of this expression pattern is not known and provides a basis for future research.

  7. Temporal asymmetries in auditory coding and perception reflect multi-layered nonlinearities.

    Science.gov (United States)

    Deneux, Thomas; Kempf, Alexandre; Daret, Aurélie; Ponsot, Emmanuel; Bathellier, Brice

    2016-01-01

    Sound recognition relies not only on spectral cues, but also on temporal cues, as demonstrated by the profound impact of time reversals on perception of common sounds. To address the coding principles underlying such auditory asymmetries, we recorded a large sample of auditory cortex neurons using two-photon calcium imaging in awake mice, while playing sounds ramping up or down in intensity. We observed clear asymmetries in cortical population responses, including stronger cortical activity for up-ramping sounds, which matches perceptual saliency assessments in mice and previous measures in humans. Analysis of cortical activity patterns revealed that auditory cortex implements a map of spatially clustered neuronal ensembles, detecting specific combinations of spectral and intensity modulation features. Comparing different models, we show that cortical responses result from multi-layered nonlinearities, which, contrary to standard receptive field models of auditory cortex function, build divergent representations of sounds with similar spectral content, but different temporal structure. PMID:27580932

  8. Pulmonary thromboembolism in cats.

    Science.gov (United States)

    Schermerhorn, Thomas; Pembleton-Corbett, Julie R; Kornreich, Bruce

    2004-01-01

    Pulmonary thromboembolism (PTE) is rarely diagnosed in cats, and the clinical features of the disease are not well known. PTE was diagnosed at postmortem examination in 17 cats, a prevalence of 0.06% over a 24-year period. The age of affected cats ranged from 10 months to 18 years, although young (10 years) cats were more commonly affected than were middle-aged cats. Males and females were equally affected. The majority of cats with PTE (n = 16) had concurrent disease, which was often severe. The most common diseases identified in association with PTE were neoplasia, anemia of unidentified cause, and pancreatitis. Cats with glomerulonephritis, encephalitis, pneumonia, heart disease, and hepatic lipidosis were also represented in this study. Most cats with PTE demonstrated dyspnea and respiratory distress before death or euthanasia, but PTE was not recognized ante mortem in any cat studied. In conclusion, PTE can affect cats of any age and is associated with a variety of systemic and inflammatory disorders. It is recommended that the same clinical criteria used to increase the suspicion of PTE in dogs should also be applied to cats. PMID:15320593

  9. A Catalogue of Anatomical Fugitive Sheets: Cat. 1-10

    OpenAIRE

    1999-01-01

    Images Cat. 1 Cat. 2 (a) Cat. 2 (b) Cat. 2 (c) Cat. 2 (d) Cat. 2 (e) Cat. 2 (f) Cat. 3: 1 (a) Cat. 3: 1 (b) Cat. 3: 2 (a) Cat. 3: 2 (b) Cat. 4: 1 Cat. 4: 2 Cat. 6: 1 (a) Cat. 6: 1 (b) Cat. 6: 2 (a) Cat. 6: 2 (b) Cat. 7: 1 (a) Cat. 7: 1 (b) Cat. 7: 2 (a) Cat. 7: 2 (b) Cat. 8: 1 Cat. 9: 1 Cat. 9: 2 Cat. 10: 1 Cat. 10: 2

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

    Science.gov (United States)

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

    2015-07-01

    Conventionally, sensory systems are viewed as separate entities, each with its own physiological process serving a different purpose. However, many functions require integrative inputs from multiple sensory systems and sensory intersection and convergence occur throughout the central nervous system. The neural processes for hearing perception undergo significant modulation by the two other major sensory systems, vision and somatosensation. This synthesis occurs at every level of the ascending auditory pathway: the cochlear nucleus, inferior colliculus, medial geniculate body and the auditory cortex. In this review, we explore the process of multisensory integration from (1) anatomical (inputs and connections), (2) physiological (cellular responses), (3) functional and (4) pathological aspects. We focus on the convergence between auditory and somatosensory inputs in each ascending auditory station. This review highlights the intricacy of sensory processing and offers a multisensory perspective regarding the understanding of sensory disorders. PMID:25526698

  11. 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.

  12. Functional neuroanatomy of auditory scene analysis in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Hannah L. Golden

    2015-01-01

    Full Text Available 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 ‘background’. Patients with typical amnestic Alzheimer's disease (n = 13 and age-matched healthy individuals (n = 17 underwent functional 3T-MRI using a sparse acquisition protocol with passive listening to auditory stimulus conditions comprising the participant's own name interleaved with or superimposed on multi-talker babble, and spectrally rotated (unrecognisable analogues of these conditions. Name identification (conditions containing the participant's own name contrasted with spectrally rotated analogues produced extensive bilateral activation involving superior temporal cortex in both the AD and healthy control groups, with no significant differences between groups. Auditory object segregation (conditions with interleaved name sounds contrasted with superimposed name sounds produced activation of right posterior superior temporal cortex in both groups, again with no differences between groups. However, the cocktail party effect (interaction of own name identification with auditory object segregation processing produced activation of right supramarginal gyrus in the AD group that was significantly enhanced compared with the healthy control group. The findings delineate an altered functional neuroanatomical profile of auditory scene analysis in Alzheimer's disease that may constitute a novel computational signature of this neurodegenerative pathology.

  13. Functional neuroanatomy of auditory scene analysis in Alzheimer's disease.

    Science.gov (United States)

    Golden, Hannah L; Agustus, Jennifer L; Goll, Johanna C; Downey, Laura E; Mummery, Catherine J; Schott, Jonathan M; Crutch, Sebastian J; Warren, Jason D

    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 'background'. Patients with typical amnestic Alzheimer's disease (n = 13) and age-matched healthy individuals (n = 17) underwent functional 3T-MRI using a sparse acquisition protocol with passive listening to auditory stimulus conditions comprising the participant's own name interleaved with or superimposed on multi-talker babble, and spectrally rotated (unrecognisable) analogues of these conditions. Name identification (conditions containing the participant's own name contrasted with spectrally rotated analogues) produced extensive bilateral activation involving superior temporal cortex in both the AD and healthy control groups, with no significant differences between groups. Auditory object segregation (conditions with interleaved name sounds contrasted with superimposed name sounds) produced activation of right posterior superior temporal cortex in both groups, again with no differences between groups. However, the cocktail party effect (interaction of own name identification with auditory object segregation processing) produced activation of right supramarginal gyrus in the AD group that was significantly enhanced compared with the healthy control group. The findings delineate an altered functional neuroanatomical profile of auditory scene analysis in Alzheimer's disease that may constitute a novel computational signature of this neurodegenerative pathology. PMID:26029629

  14. A Catalogue of Anatomical Fugitive Sheets: Cat. 11-25

    OpenAIRE

    1999-01-01

    Images Cat. 11 (a) Cat. 11 (b) Cat. 11 (c) Cat. 11 (d) Cat. 12: 1 (a) Cat. 12: 1 (b) Cat. 12: 2 (a) Cat. 12: 2 (b) Cat. 13 Cat. 14 (a) Cat. 14 (b) Cat. 14 (c) Cat. 15 (a) Cat. 15 (b) Cat. 17: 1 Cat. 17: 2 Cat. 18: 1 Cat. 18: 2 Cat. 19: 1 (a) Cat. 19: 1 (b) Cat. 19: 2 (a) Cat. 19: 2 (b) Cat. 20: 1 Cat. 20: 2 (a) Cat. 20: 2 (b) Cat. 21 (a) Cat. 21 (b) Cat. 21 (c) Cat. 21 (d) Cat. 21 (e) Cat. 22 Cat. 24: 1 and 2 Cat. 25: 1 Cat. 25: 2 Cat. 25: 3 Cat. 25: 4

  15. 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.

  16. A tortoiseshell male cat

    DEFF Research Database (Denmark)

    Pedersen, A. S.; Berg, Lise Charlotte; Almstrup, Kristian;

    2014-01-01

    Tortoiseshell coat color is normally restricted to female cats due to X-linkage of the gene that encodes the orange coat color. Tortoiseshell male cats do, however, occur at a low frequency among tortoiseshell cats because of chromosome aberrations similar to the Klinefelter syndrome in man...... tissue from a tortoiseshell male cat referred to us. Chromosome analysis using RBA-banding consistently revealed a 39,XXY karyotype. Histological examinations of testis biopsies from this cat showed degeneration of the tubules, hyperplasia of the interstitial tissue, and complete loss of germ cells....... Immunostaining using anti-vimentin and anti-VASA (DDX4) showed that only Sertoli cells and no germ cells were observed in the testicular tubules. As no sign of spermatogenesis was detected, we conclude that this is a classic case of a sterile, male tortoiseshell cat with a 39,XXY chromosome complement. © 2013 S...

  17. Modality-specific involvement of occipital cortex in the early blind

    NARCIS (Netherlands)

    Lubbe, van der R.H.J.; Mierlo, van C.M.; Postma, A.

    2008-01-01

    What happens in occipital cortex when neuronal activity is no longer evoked by regular visual stimulation? Studying brain activity induced by tactile and auditory stimuli in the blind may provide an answer. Several studies indicate that occipital cortex in the blind is recruited in simple tasks, lik

  18. 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

  19. 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

  20. Diffusion tensor imaging of dolphin brains reveals direct auditory pathway to temporal lobe.

    Science.gov (United States)

    Berns, Gregory S; Cook, Peter F; Foxley, Sean; Jbabdi, Saad; Miller, Karla L; Marino, Lori

    2015-07-22

    The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes' auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of 'associative' regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here, we used a novel diffusion tensor imaging (DTI) sequence in archival post-mortem brains of a common dolphin (Delphinus delphis) and a pantropical dolphin (Stenella attenuata) to map their sensory and motor systems. Using thalamic parcellation based on traditionally defined regions for the primary visual (V1) and auditory cortex (A1), we found distinct regions of the thalamus connected to V1 and A1. But in addition to suprasylvian-A1, we report here, for the first time, the auditory cortex also exists in the temporal lobe, in a region near cetacean-A2 and possibly analogous to the primary auditory cortex in related terrestrial mammals (Artiodactyla). Using probabilistic tract tracing, we found a direct pathway from the inferior colliculus to the medial geniculate nucleus to the temporal lobe near the sylvian fissure. Our results demonstrate the feasibility of post-mortem DTI in archival specimens to answer basic questions in comparative neurobiology in a way that has not previously been possible and shows a link between the cetacean auditory system and those of terrestrial mammals. Given that fresh cetacean specimens are relatively rare, the ability to measure connectivity in archival specimens opens up a plethora of possibilities for investigating neuroanatomy in cetaceans and other species

  1. Neuromagnetic evidence for early auditory restoration of fundamental pitch.

    Directory of Open Access Journals (Sweden)

    Philip J Monahan

    Full Text Available BACKGROUND: Understanding the time course of how listeners reconstruct a missing fundamental component in an auditory stimulus remains elusive. We report MEG evidence that the missing fundamental component of a complex auditory stimulus is recovered in auditory cortex within 100 ms post stimulus onset. METHODOLOGY: Two outside tones of four-tone complex stimuli were held constant (1200 Hz and 2400 Hz, while two inside tones were systematically modulated (between 1300 Hz and 2300 Hz, such that the restored fundamental (also knows as "virtual pitch" changed from 100 Hz to 600 Hz. Constructing the auditory stimuli in this manner controls for a number of spectral properties known to modulate the neuromagnetic signal. The tone complex stimuli only diverged on the value of the missing fundamental component. PRINCIPAL FINDINGS: We compared the M100 latencies of these tone complexes to the M100 latencies elicited by their respective pure tone (spectral pitch counterparts. The M100 latencies for the tone complexes matched their pure sinusoid counterparts, while also replicating the M100 temporal latency response curve found in previous studies. CONCLUSIONS: Our findings suggest that listeners are reconstructing the inferred pitch by roughly 100 ms after stimulus onset and are consistent with previous electrophysiological research suggesting that the inferential pitch is perceived in early auditory cortex.

  2. 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...

  3. Activity of the motor cortex during scratching.

    Science.gov (United States)

    Sirota, Mikhail G; Pavlova, Galina A; Beloozerova, Irina N

    2006-02-01

    In awake cats sitting with the head restrained, scratching was evoked using stimulation of the ear. Cats scratched the shoulder area, consistently failing to reach the ear. Kinematics of the hind limb movements and the activity of ankle muscles, however, were similar to those reported earlier in unrestrained cats. The activity of single neurons in the hind limb representation of the motor cortex, including pyramidal tract neurons (PTNs), was examined. During the protraction stage of the scratch response, the activity in 35% of the neurons increased and in 50% decreased compared with rest. During the rhythmic stage, the motor cortex population activity was approximately two times higher compared with rest, because the activity of 53% of neurons increased and that of 33% decreased in this stage. The activity of 61% of neurons was modulated in the scratching rhythm. The average depth of frequency modulation was 12.1 +/- 5.3%, similar to that reported earlier for locomotion. The phases of activity of different neurons were approximately evenly distributed over the scratch cycle. There was no simple correlation between resting receptive field properties and the activity of neurons during the scratch response. We conclude that the motor cortex participates in both the protraction and the rhythmic stages of the scratch response. PMID:16236789

  4. Auditory Cortical Plasticity Drives Training-Induced Cognitive Changes in Schizophrenia.

    Science.gov (United States)

    Dale, Corby L; Brown, Ethan G; Fisher, Melissa; Herman, Alexander B; Dowling, Anne F; Hinkley, Leighton B; Subramaniam, Karuna; Nagarajan, Srikantan S; Vinogradov, Sophia

    2016-01-01

    Schizophrenia is characterized by dysfunction in basic auditory processing, as well as higher-order operations of verbal learning and executive functions. We investigated whether targeted cognitive training of auditory processing improves neural responses to speech stimuli, and how these changes relate to higher-order cognitive functions. Patients with schizophrenia performed an auditory syllable identification task during magnetoencephalography before and after 50 hours of either targeted cognitive training or a computer games control. Healthy comparison subjects were assessed at baseline and after a 10 week no-contact interval. Prior to training, patients (N = 34) showed reduced M100 response in primary auditory cortex relative to healthy participants (N = 13). At reassessment, only the targeted cognitive training patient group (N = 18) exhibited increased M100 responses. Additionally, this group showed increased induced high gamma band activity within left dorsolateral prefrontal cortex immediately after stimulus presentation, and later in bilateral temporal cortices. Training-related changes in neural activity correlated with changes in executive function scores but not verbal learning and memory. These data suggest that computerized cognitive training that targets auditory and verbal learning operations enhances both sensory responses in auditory cortex as well as engagement of prefrontal regions, as indexed during an auditory processing task with low demands on working memory. This neural circuit enhancement is in turn associated with better executive function but not verbal memory. PMID:26152668

  5. A Mediating Role of the Premotor Cortex in Phoneme Segmentation

    Science.gov (United States)

    Sato, Marc; Tremblay, Pascale; Gracco, Vincent L.

    2009-01-01

    Consistent with a functional role of the motor system in speech perception, disturbing the activity of the left ventral premotor cortex by means of repetitive transcranial magnetic stimulation (rTMS) has been shown to impair auditory identification of syllables that were masked with white noise. However, whether this region is crucial for speech…

  6. That Fat Cat

    Science.gov (United States)

    Lambert, Phyllis Gilchrist

    2012-01-01

    This activity began with a picture book, Nurit Karlin's "Fat Cat On a Mat" (HarperCollins; 1998). The author and her students started their project with a 5-inch circular template for the head of their cats. They reviewed shapes as they drew the head and then added the ears and nose, which were triangles. Details to the face were added when…

  7. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Dictionary of Medical Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, ... Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A ...

  8. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Skiing, Snowboarding, Skating Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de ...

  9. Auditory Integration Training

    Directory of Open Access Journals (Sweden)

    Zahra Jafari

    2002-07-01

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

  10. CAT questions and answers

    International Nuclear Information System (INIS)

    This document, prepared in February 1993, addresses the most common questions asked by APS Collaborative Access Teams (CATs). The answers represent the best judgment on the part of the APS at this time. In some cases, details are provided in separate documents to be supplied by the APS. Some of the answers are brief because details are not yet available. The questions are separated into five categories representing different aspects of CAT interactions with the APS: (1) Memorandum of Understanding (MOU), (2) CAT Beamline Review and Construction, (3) CAT Beamline Safety, (4) CAT Beamline Operations, and (5) Miscellaneous. The APS plans to generate similar documents as needed to both address new questions and clarify answers to present questions

  11. Auditory Neuropathy: Findings of Behavioral, Physiological and Neurophysiological Tests

    Directory of Open Access Journals (Sweden)

    Mohammad Farhadi

    2006-12-01

    Full Text Available Background and Aim: Auditory neuropathy (AN can be diagnosed by abnormal auditory brainstem response (ABR, in the presence of normal cochlear microphonic (CM and otoacoustic emissions (OAEs.The aim of this study was to investigate the ABR and other electrodiagnostic test results of 6 patients suspicious to AN with problems in speech recognition. Materials and Methods: this cross sectional study was conducted on 6 AN patients with different ages evaluated by pure tone audiometry, speech discrimination score (SDS , immittance audiometry. ElectroCochleoGraphy , ABR, middle latency response (MLR, Late latency response (LLR, and OAEs. Results: Behavioral pure tone audiometric tests showed moderate to profound hearing loss. SDS was so poor which is not in accordance with pure tone thresholds. All patients had normal tympanogram but absent acoustic reflexes. CMs and OAEs were within normal limits. There was no contra lateral suppression of OAEs. None of cases had normal ABR or MLR although LLR was recorded in 4. Conclusion: All patients in this study are typical cases of auditory neuropathy. Despite having abnormal input, LLR remains normal that indicates differences in auditory evoked potentials related to required neural synchrony. These findings show that auditory cortex may play a role in regulating presentation of deficient signals along auditory pathways in primary steps.

  12. 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 ...

  13. [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

  14. Hierarchical and serial processing in the spatial auditory cortical pathway is degraded by natural aging

    OpenAIRE

    Juarez-Salinas, Dina L.; Engle, James R.; Navarro, Xochi O.; Gregg H Recanzone

    2010-01-01

    The compromised abilities to localize sounds and to understand speech are two hallmark deficits in aged individuals. The auditory cortex is necessary for these processes, yet we know little about how normal aging affects these early cortical fields. In this study, we recorded the spatial tuning of single neurons in primary (area A1) and secondary (area CL) auditory cortical areas in young and aged alert rhesus macaques. We found that the neurons of aged animals had greater spontaneous and dri...

  15. Neural Coding of Sound Intensity and Loudness in the Human Auditory System

    OpenAIRE

    Röhl, Markus; Uppenkamp, Stefan

    2012-01-01

    Inter-individual differences in loudness sensation of 45 young normal-hearing participants were employed to investigate how and at what stage of the auditory pathway perceived loudness, the perceptual correlate of sound intensity, is transformed into neural activation. Loudness sensation was assessed by categorical loudness scaling, a psychoacoustical scaling procedure, whereas neural activation in the auditory cortex, inferior colliculi, and medial geniculate bodies was investigated with fun...

  16. Effect of aging on GAD levels in the central auditory system of the rat

    Czech Academy of Sciences Publication Activity Database

    Burianová, Jana; Ouda, Ladislav; Profant, Martin; Syka, Josef

    Geneva : Federation of European Neurosciences Societies, 2008. s. 188.6. [FENS. Forum of European Neuroscience /6./. 12.07.2008-16.07.2008, Geneva] R&D Projects: GA ČR GA309/07/1336; GA MZd NR8113; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390512 Keywords : Auditory * Auditory cortex Subject RIV: FH - Neurology

  17. Polarity-specific transcranial direct current stimulation disrupts auditory pitch learning.

    Science.gov (United States)

    Matsushita, Reiko; Andoh, Jamila; Zatorre, Robert J

    2015-01-01

    Transcranial direct current stimulation (tDCS) is attracting increasing interest because of its potential for therapeutic use. While its effects have been investigated mainly with motor and visual tasks, less is known in the auditory domain. Past tDCS studies with auditory tasks demonstrated various behavioral outcomes, possibly due to differences in stimulation parameters, task-induced brain activity, or task measurements used in each study. Further research, using well-validated tasks is therefore required for clarification of behavioral effects of tDCS on the auditory system. Here, we took advantage of findings from a prior functional magnetic resonance imaging study, which demonstrated that the right auditory cortex is modulated during fine-grained pitch learning of microtonal melodic patterns. Targeting the right auditory cortex with tDCS using this same task thus allowed us to test the hypothesis that this region is causally involved in pitch learning. Participants in the current study were trained for 3 days while we measured pitch discrimination thresholds using microtonal melodies on each day using a psychophysical staircase procedure. We administered anodal, cathodal, or sham tDCS to three groups of participants over the right auditory cortex on the second day of training during performance of the task. Both the sham and the cathodal groups showed the expected significant learning effect (decreased pitch threshold) over the 3 days of training; in contrast we observed a blocking effect of anodal tDCS on auditory pitch learning, such that this group showed no significant change in thresholds over the 3 days. The results support a causal role for the right auditory cortex in pitch discrimination learning. PMID:26041982

  18. Dynamic faces speed up the onset of auditory cortical spiking responses during vocal detection

    OpenAIRE

    Chandrasekaran, Chandramouli; Lemus, Luis; Asif A Ghazanfar

    2013-01-01

    We combine facial motion with voices to help us hear better, but the role that low-level sensory areas such as the auditory cortex may play in this process is unclear. We combined a vocalization detection task with auditory cortical physiology in monkeys to bridge this epistemic gap. Surprisingly, and contrary to previous assumptions and hypotheses, changes in firing rate had no clear relationship to the detection advantage that dynamic faces provided when listening for vocalizations. Instead...

  19. Polarity-Specific Transcranial Direct Current Stimulation Disrupts Auditory Pitch Learning

    Directory of Open Access Journals (Sweden)

    Reiko eMatsushita

    2015-05-01

    Full Text Available Transcranial direct current stimulation (tDCS is attracting increasing interest because of its potential for therapeutic use. While its effects have been investigated mainly with motor and visual tasks, less is known in the auditory domain. Past tDCS studies with auditory tasks demonstrated various behavioural outcomes, possibly due to differences in stimulation parameters or task measurements used in each study. Further research using well-validated tasks are therefore required for clarification of behavioural effects of tDCS on the auditory system. Here, we took advantage of findings from a prior functional magnetic resonance imaging study, which demonstrated that the right auditory cortex is modulated during fine-grained pitch learning of microtonal melodic patterns. Targeting the right auditory cortex with tDCS using this same task thus allowed us to test the hypothesis that this region is causally involved in pitch learning. Participants in the current study were trained for three days while we measured pitch discrimination thresholds using microtonal melodies on each day using a psychophysical staircase procedure. We administered anodal, cathodal, or sham tDCS to three groups of participants over the right auditory cortex on the second day of training during performance of the task. Both the sham and the cathodal groups showed the expected significant learning effect (decreased pitch threshold over the three days of training; in contrast we observed a blocking effect of anodal tDCS on auditory pitch learning, such that this group showed no significant change in thresholds over the three days. The results support a causal role for the right auditory cortex in pitch discrimination learning.

  20. Orientation-tuned surround suppression in mouse visual cortex

    NARCIS (Netherlands)

    Self, Matthew W; Lorteije, Jeannette A M; Vangeneugden, Joris; van Beest, Enny H; Grigore, Mihaela E; Levelt, Christiaan N; Heimel, J.A.; Roelfsema, Pieter R

    2014-01-01

    The firing rates of neurons in primary visual cortex (V1) are suppressed by large stimuli, an effect known as surround suppression. In cats and monkeys, the strength of suppression is sensitive to orientation; responses to regions containing uniform orientations are more suppressed than those contai

  1. 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.

  2. Changes in the axonal conduction velocity of pyramidal tract neurons in the aged cat.

    Science.gov (United States)

    Xi, M C; Liu, R H; Engelhardt, J K; Morales, F R; Chase, M H

    1999-01-01

    The present study was undertaken to determine whether age-dependent changes in axonal conduction velocity occur in pyramidal tract neurons. A total of 260 and 254 pyramidal tract neurons were recorded extracellularly in the motor cortex of adult control and aged cats, respectively. These cells were activated antidromically by electrical stimulation of the medullary pyramidal tract. Fast- and slow-conducting neurons were identified according to their axonal conduction velocity in both control and aged cats. While 51% of pyramidal tract neurons recorded in the control cats were fast conducting (conduction velocity greater than 20 m/s), only 26% of pyramidal tract neurons in the aged cats were fast conducting. There was a 43% decrease in the median conduction velocity for the entire population of pyramidal tract neurons in aged cats when compared with that of pyramidal tract neurons in the control cats (P cats. However, the regression slope was significantly reduced in aged cats. This reduction was due to the appearance of a group of pyramidal tract neurons with relatively shorter spike durations but slower axonal conduction velocities in the aged cat. Sample intracellular data confirmed the above results. These observations form the basis for the following conclusions: (i) there is a decrease in median conduction velocity of pyramidal tract neurons in aged cats; (ii) the reduction in the axonal conduction velocity of pyramidal tract neurons in aged cats is due, in part, to fibers that previously belonged to the fast-conducting group and now conduct at slower velocity. PMID:10392844

  3. StreamCat

    Data.gov (United States)

    U.S. Environmental Protection Agency — The StreamCat Dataset provides summaries of natural and anthropogenic landscape features for ~2.65 million streams, and their associated catchments, within the...

  4. Neural correlates of auditory temporal predictions during sensorimotor synchronization

    Directory of Open Access Journals (Sweden)

    Nadine ePecenka

    2013-08-01

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

  5. Visual-induced expectations modulate auditory cortical responses

    OpenAIRE

    van Wassenhove, Virginie; Grzeczkowski, Lukasz

    2015-01-01

    Active sensing has important consequences on multisensory processing (Schroeder et al., 2010). Here, we asked whether in the absence of saccades, the position of the eyes and the timing of transient color changes of visual stimuli could selectively affect the excitability of auditory cortex by predicting the “where” and the “when” of a sound, respectively. Human participants were recorded with magnetoencephalography (MEG) while maintaining the position of their eyes on the left, right, or cen...

  6. Haemobartonellosis in Van Cats

    OpenAIRE

    AKKAN, Hasan Altan; Karaca, Mehmet; TÜTÜNCÜ, Mehmet

    2005-01-01

    The present study was conducted to determine prevalence of Haemobartonella felis in Van cats. 121 Van cats (82 female, 39 male, aged 1-9 years) were the materials of the study. To determine biochemical and haematological parameters, 2 ml blood with and without anticoagulant were taken according to technique from vena cephalica antebrachii. H. felis was detected in blood smears preparations of 18 (14.88%) by Papenheim staining. Among biochemical parameters aspartate amino transferase (AST), al...

  7. Resolving Schrodinger's cat

    OpenAIRE

    Hobson, Art

    2016-01-01

    Schrodinger's famous cat has long been misunderstood. According to quantum theory and experiments with entangled systems, an entangled state such as the Schrodinger's cat state is neither a superposition of states of either subsystem nor a superposition of compound states of the composite system, but rather a nonlocal superposition of correlations between pairs of states of the two subsystems. The entangled post-measurement state that results from an ideal measurement is not paradoxical, but ...

  8. Cardiac Biomarkers in Hyperthyroid Cats

    OpenAIRE

    Sangster, Jodi Kirsten

    2013-01-01

    Background: Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT-proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been as extensively investigated in hyperthyroidism.Hypothesis: Plasma NT-proBNP and cTNI concentrations are higher in cats with primary cardiac disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats.Animals: Twenty-three hyperthyr...

  9. Cardiac Biomarkers in Hyperthyroid Cats

    OpenAIRE

    Sangster, J.K.; Panciera, D L; Abbott, J.A.; Zimmerman, K.C.; Lantis, A.C.

    2013-01-01

    Background Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT‐proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been extensively investigated in hyperthyroidism. Hypothesis Plasma NT‐proBNP and cTNI concentrations are higher in cats with primary myocardial disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats. Animals Twenty‐three hyperthyro...

  10. 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.

  11. The Effects of Auditory Contrast Tuning upon Speech Intelligibility.

    Science.gov (United States)

    Killian, Nathan J; Watkins, Paul V; Davidson, Lisa S; Barbour, Dennis L

    2016-01-01

    We have previously identified neurons tuned to spectral contrast of wideband sounds in auditory cortex of awake marmoset monkeys. Because additive noise alters the spectral contrast of speech, contrast-tuned neurons, if present in human auditory cortex, may aid in extracting speech from noise. Given that this cortical function may be underdeveloped in individuals with sensorineural hearing loss, incorporating biologically-inspired algorithms into external signal processing devices could provide speech enhancement benefits to cochlear implantees. In this study we first constructed a computational signal processing algorithm to mimic auditory cortex contrast tuning. We then manipulated the shape of contrast channels and evaluated the intelligibility of reconstructed noisy speech using a metric to predict cochlear implant user perception. Candidate speech enhancement strategies were then tested in cochlear implantees with a hearing-in-noise test. Accentuation of intermediate contrast values or all contrast values improved computed intelligibility. Cochlear implant subjects showed significant improvement in noisy speech intelligibility with a contrast shaping procedure. PMID:27555826

  12. 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.

  13. Plasticity of the human auditory cortex related to musical training.

    Science.gov (United States)

    Pantev, Christo; Herholz, Sibylle C

    2011-11-01

    During the last decades music neuroscience has become a rapidly growing field within the area of neuroscience. Music is particularly well suited for studying neuronal plasticity in the human brain because musical training is more complex and multimodal than most other daily life activities, and because prospective and professional musicians usually pursue the training with high and long-lasting commitment. Therefore, music has increasingly been used as a tool for the investigation of human cognition and its underlying brain mechanisms. Music relates to many brain functions like perception, action, cognition, emotion, learning and memory and therefore music is an ideal tool to investigate how the human brain is working and how different brain functions interact. Novel findings have been obtained in the field of induced cortical plasticity by musical training. The positive effects, which music in its various forms has in the healthy human brain are not only important in the framework of basic neuroscience, but they also will strongly affect the practices in neuro-rehabilitation. PMID:21763342

  14. Functional Changes in the Human Auditory Cortex in Ageing

    Czech Academy of Sciences Publication Activity Database

    Profant, Oliver; Tintěra, J.; Balogová, Zuzana; Ibrahim, I.; Jílek, Milan; Syka, Josef

    2015-01-01

    Roč. 10, č. 3 (2015), e0116692. E-ISSN 1932-6203 R&D Projects: GA ČR GAP304/10/1872; GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:68378041 Keywords : age-related-changes * hearing-loss * hemispheric-asymmetry * speech-perception * elderly listeners * cognitive decline * neural mechanisms * working-memory * older-adults * presbycusis Subject RIV: FH - Neurology Impact factor: 3.234, year: 2014

  15. 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

  16. 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...

  17. 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...

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

    Directory of Open Access Journals (Sweden)

    Feng eRong

    2011-05-01

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

  19. 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

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

    Science.gov (United States)

    Kikuchi, Yukiko; Horwitz, Barry; Mishkin, Mortimer

    2010-09-29

    Connectional anatomical evidence suggests that the auditory core, containing the tonotopic areas A1, R, and RT, constitutes the first stage of auditory cortical processing, with feedforward projections from core outward, first to the surrounding auditory belt and then to the parabelt. Connectional evidence also raises the possibility that the core itself is serially organized, with feedforward projections from A1 to R and with additional projections, although of unknown feed direction, from R to RT. We hypothesized that area RT together with more rostral parts of the supratemporal plane (rSTP) form the anterior extension of a rostrally directed stimulus quality processing stream originating in the auditory core area A1. Here, we analyzed auditory responses of single neurons in three different sectors distributed caudorostrally along the supratemporal plane (STP): sector I, mainly area A1; sector II, mainly area RT; and sector III, principally RTp (the rostrotemporal polar area), including cortex located 3 mm from the temporal tip. Mean onset latency of excitation responses and stimulus selectivity to monkey calls and other sounds, both simple and complex, increased progressively from sector I to III. Also, whereas cells in sector I responded with significantly higher firing rates to the "other" sounds than to monkey calls, those in sectors II and III responded at the same rate to both stimulus types. The pattern of results supports the proposal that the STP contains a rostrally directed, hierarchically organized auditory processing stream, with gradually increasing stimulus selectivity, and that this stream extends from the primary auditory area to the temporal pole. PMID:20881120

  1. Postnatal development of the endbulb of Held in congenitally deaf cats

    Directory of Open Access Journals (Sweden)

    Christa A Baker

    2010-05-01

    Full Text Available The endbulbs of Held are formed by the ascending branches of myelinated auditory nerve fibers and represent one of the largest synaptic endings in the brain. Normally, these endings are highly branched and each can form up to 1000 dome-shaped synapses. The deaf white cat is a model of congenital deafness involving a type of cochleosaccular degeneration that mimics the Scheibe deformity in humans. Mature deaf white cats exhibit reduced endbulb branching, hypertrophy of postsynaptic densities (PSDs, and changes in synaptic vesicle density. Because cats are essentially deaf at birth, we wanted to determine if the progression of brain abnormalities was linked in time to the failure of normal hearing development. The rationale was that the lack of sound-evoked activity would trigger pathologic change in deaf kittens. The cochleae of deaf cats did not exhibit abnormal morphology at birth. After the first postnatal week, however, the presence of a collapsed scala media signaled the difference between deaf and hearing cats. By working backwards in age, endbulbs of deaf cats expressed flattened and elongated PSDs and increased synaptic vesicle density as compared to normal endbulbs. These differences are present at birth in some white kittens, presaging deafness despite their normal cochlear histology. We speculate that hearing pathology is signaled by a perinatal loss of spontaneous bursting activity in auditory nerve fibers or perhaps by some factor released by hair cell synapses before obliteration of the organ of Corti.

  2. Salicylate-Induced Auditory Perceptual Disorders and Plastic Changes in Nonclassical Auditory Centers in Rats

    Directory of Open Access Journals (Sweden)

    Guang-Di Chen

    2014-01-01

    Full Text Available Previous studies have shown that sodium salicylate (SS activates not only central auditory structures, but also nonauditory regions associated with emotion and memory. To identify electrophysiological changes in the nonauditory regions, we recorded sound-evoked local field potentials and multiunit discharges from the striatum, amygdala, hippocampus, and cingulate cortex after SS-treatment. The SS-treatment produced behavioral evidence of tinnitus and hyperacusis. Physiologically, the treatment significantly enhanced sound-evoked neural activity in the striatum, amygdala, and hippocampus, but not in the cingulate. The enhanced sound evoked response could be linked to the hyperacusis-like behavior. Further analysis showed that the enhancement of sound-evoked activity occurred predominantly at the midfrequencies, likely reflecting shifts of neurons towards the midfrequency range after SS-treatment as observed in our previous studies in the auditory cortex and amygdala. The increased number of midfrequency neurons would lead to a relative higher number of total spontaneous discharges in the midfrequency region, even though the mean discharge rate of each neuron may not increase. The tonotopical overactivity in the midfrequency region in quiet may potentially lead to tonal sensation of midfrequency (the tinnitus. The neural changes in the amygdala and hippocampus may also contribute to the negative effect that patients associate with their tinnitus.

  3. E-Z-CAT

    International Nuclear Information System (INIS)

    A new barium sulphate suspension, E-Z-CAT, for use as an oral contrast medium at computed tomography of the abdomen has been compared with the commonly used water-soluble iodinated contrast medium Gastrografin as regards patient tolerance and diagnostic information. The investigation was conducted as an unpaired randomized single-blind study in 100 consecutive patients. E-Z-CAT seems to be preferred because of its better taste, its lesser tendency to cause diarrhoea, and for usage in patients who are known to be hypersensitive to iodinated contrast media. The diagnostic information was the same for both contrast media. (Auth.)

  4. ServCat Sensitivity Guidelines

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This guide covers sensitivity in ServCat. This document provides technical guidance on how sensitivity fields work in ServCat, and provides suggestions on what...

  5. 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.

  6. 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

  7. Feature- and object-based attentional modulation in the human auditory "where" pathway.

    Science.gov (United States)

    Krumbholz, Katrin; Eickhoff, Simon B; Fink, Gereon R

    2007-10-01

    Attending to a visual stimulus feature, such as color or motion, enhances the processing of that feature in the visual cortex. Moreover, the processing of the attended object's other, unattended, features is also enhanced. Here, we used functional magnetic resonance imaging to show that attentional modulation in the auditory system may also exhibit such feature- and object-specific effects. Specifically, we found that attending to auditory motion increases activity in nonprimary motion-sensitive areas of the auditory cortical "where" pathway. Moreover, activity in these motion-sensitive areas was also increased when attention was directed to a moving rather than a stationary sound object, even when motion was not the attended feature. An analysis of effective connectivity revealed that the motion-specific attentional modulation was brought about by an increase in connectivity between the primary auditory cortex and nonprimary motion-sensitive areas, which, in turn, may have been mediated by the paracingulate cortex in the frontal lobe. The current results indicate that auditory attention can select both objects and features. The finding of feature-based attentional modulation implies that attending to one feature of a sound object does not necessarily entail an exhaustive processing of the object's unattended features. PMID:18271742

  8. 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.

  9. Cat Scratch Disease (For Parents)

    Science.gov (United States)

    ... Tropical Delight: Melon Smoothie Pregnant? Your Baby's Growth Cat Scratch Disease KidsHealth > For Parents > Cat Scratch Disease Print A A A Text Size ... Doctor en español Enfermedad por arañazo de gato Cat scratch disease is a bacterial infection that a ...

  10. Tracheal collapse in two cats

    International Nuclear Information System (INIS)

    Two cats examined bronchoscopically to discover the cause of tracheal collapse were found to have tracheal obstruction cranial to the collapse. Cats with this unusual sign should be examined bronchoscopically to ascertain whether there is an obstruction, as the cause in these 2 cats was distinct from the diffuse airway abnormality that causes tracheal collapse in dogs

  11. Membranous nephropathy in sibling cats.

    Science.gov (United States)

    Nash, A S; Wright, N G

    1983-08-20

    Membranous nephropathy was diagnosed in two sibling cats from the same household. Both cases presented with the nephrotic syndrome but 33 months elapsed before the second cat became ill, by which time the first cat had been in full clinical remission for over a year. PMID:6623883

  12. 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 (

  13. Taxonomy Icon Data: domestic cat [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available domestic cat ... Felis silvestris cat us Chordata/Vertebrata/Mammalia/Theria/Eutheria/Carnivora Felis ... _silvestris_cat us_L.png Felis_silvestris_cat us_NL.png Felis_silves ... tris_cat us_S.png Felis_silvestris_cat us_NS.png http://biosc ...

  14. Getting a CAT Scan

    Medline Plus

    Full Text Available ... More Quizzes Kids' Dictionary of Medical Words En Español What Other Kids Are Reading Back-to-School ... Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands ...

  15. Chemodectoma in a cat

    International Nuclear Information System (INIS)

    A 10-year-old, spayed female, domestic shorthair cat was presented for evaluation of a thoracic mass. Radiographs demonstrated a 4 by 5-cm mass dorsal to the heart. Cytology of specimens obtained by ultrasound-guided needle aspiration was compatible with a neuroendocrine tumor. Scintigraphy, thoracic exploratory, and histology were used to identify the mass as an aortic body chemodectoma

  16. Coxofemoral luxations in cats

    International Nuclear Information System (INIS)

    In a retrospective study, 79 untreated luxations of the coxofemoral joint in cats were recorded over a 12-year period. Twenty-nine of these cases were available for follow-up, of which 13 were re-examined clinically and radiologically. It was found that the maximum incidence of the injury occurred from one to three years of age. Follow-up radiographs showed that the cats had developed nearthroses of various degrees located dorsally on the ilium. The degree of nearthrosis formation was not consistently correlated with the length of the observation time. Radiological signs of decreased bone density of the proximal femur may be caused by reduced weightbearing related to changes in biomechanical function and altered blood supply in the luxated limb. Almost two-thirds of the re-examined animals presented some kind of locomotor dysfunction on clinical examination. Limb function improved with time. The best clinical results appeared to be in cats that were immature at the time of injury and developed nearthrosis similar to a normal coxofemoral joint. All the cats available to this study showed acceptable functional results and had a normal level of activity according to the owners

  17. Getting a CAT Scan

    Medline Plus

    Full Text Available ... More Quizzes Kids' Dictionary of Medical Words En Español What Other Kids Are Reading Movie: Digestive System ... Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands ...

  18. The Fishing Cat

    Institute of Scientific and Technical Information of China (English)

    孙雅飞; 乐伟国

    2008-01-01

    @@ 一、故事内容 A cat goes fishing every day. He wants to eat fish, but he can't catch any fish. One day, he goes to the river as usual. Suddenly, a fish comes out. He catches the fish and putsthe fish in the basket. He's very happy, but he forgest to put the lid on the basket.

  19. Oligopsonistic Cats and Dogs

    OpenAIRE

    Dewit, Dr. Gerda; Leahy, Dr. Dermot

    2005-01-01

    We study the strategic investment behaviour of oligopsonistic rivals in the labour market. Under wage competition, firms play "puppy dog" with productivityaugmenting investment and "fat cat" with supply-enhancing investment. Under employment competition, investing strategically always involves playing "top dog".

  20. Developing Neocortex Organization and Connectivity in Cats Revealed by Direct Correlation of Diffusion Tractography and Histology

    OpenAIRE

    Takahashi, Emi; Dai, Guangping; Glenn D. Rosen; Wang, Ruopeng; Ohki, Kenichi; Rebecca D. Folkerth; Galaburda, Albert M.; Wedeen, Van J.; P. Ellen Grant

    2010-01-01

    The immature cortex (cortical plate [CP]) and underlying subplate (SP), a transient cell layer just below the CP, play critical roles in the formation of intracerebral connections. The purpose of this study was to examine the diffusion characteristics of the developing cortex and subcortical structures and compare to histology. We obtained high-resolution diffusion spectrum images of postnatal day (P) 0 (newborn), P35 (pediatric), and P100 (adult) cat brains, performed tractography analysis, ...

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

    Science.gov (United States)

    Furman-Haran, Edna; Arzi, Anat; Levkovitz, Yechiel; Malach, Rafael

    2016-01-01

    Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI) during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM) sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG) cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations. PMID:27310812

  2. [The auditory pathway: levels of integration of information and principal neurotransmitters].

    Science.gov (United States)

    Hernández-Zamora, Edgar; Poblano, Adrián

    2014-01-01

    In this paper we studied the central auditory pathway (CAP) from an anatomical, physiological and neurochemical standpoint, from the inner ear, brainstem, thalamus to the temporal auditory cortex. The characteristics of the spiral ganglion of Corti, auditory nerve, cochlear nuclei, superior olivary complex, lateral lemniscus, inferior colliculus, medial geniculate body, and auditory cortex, including the auditory efferent pathway, are given. CAP is described as the electrical impulses, travelling through axons, allowing ions to enter a neuron and vesicles with neurotransmitters (NT) and then released into synaptic space. The NT changes the functioning of the cells; when attached to specific receptors on the next nerve cell, NT-receiver union causes input of ions through Gap sites, resulting in a postsynaptic potential that is spread over all CAP. In addition, the effects of the NT are not limited to the transmission, but as trophic agents that promote the formation of new neural networks. Even the anatomy, physiology, neurochemical aspects, and the different types of synapses are not fully understood to comprehend the organization of the CAP, but remain under investigation because of the relevance for the treatment of various central auditory disorders. PMID:25275847

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

    Directory of Open Access Journals (Sweden)

    Meytal Wilf

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

  4. "Visual" Cortex Responds to Spoken Language in Blind Children

    OpenAIRE

    Bedny, Marina; Richardson, Hilary; Saxe, Rebecca R.

    2015-01-01

    Plasticity in the visual cortex of blind individuals provides a rare window into the mechanisms of cortical specialization. In the absence of visual input, occipital (“visual”) brain regions respond to sound and spoken language. Here, we examined the time course and developmental mechanism of this plasticity in blind children. Nineteen blind and 40 sighted children and adolescents (4–17 years old) listened to stories and two auditory control conditions (unfamiliar foreign speech, and music). ...

  5. 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…

  6. The insular cortex: a comparative perspective.

    Science.gov (United States)

    Butti, Camilla; Hof, Patrick R

    2010-06-01

    The human insular cortex is involved in a variety of viscerosensory, visceromotor, and interoceptive functions, and plays a role in complex processes such as emotions, music, and language. Across mammals, the insula has considerable morphologic variability. We review the structure and connectivity of the insula in laboratory animals (mouse, domestic cat, macaque monkey), and we present original data on the morphology and cytoarchitecture of insular cortex in less common species including a large carnivore (the Atlantic walrus, Odobenus rosmarus), two artiodactyls (the pigmy hippopotamus, Hexaprotodon liberiensis, and the Western bongo, Tragelaphus eurycerus), two cetaceans (the beluga whale, Delphinapterus leucas, and the minke whale, Balaenoptera acutorostrata), and a sirenian (the Florida manatee, Trichechus manatus latirostris). The insula shows substantial variability in shape, extent, and gyral and sulcal patterns, as well as differences in laminar organization, cellular specialization, and structural association with the claustrum. Our observations reveal that the insular cortex is extremely variable among mammals. These differences could be related to the role exerted by specific and selective pressures on cortical structure during evolution. We conclude that it is not possible to identify a general model of organization for the mammalian insular cortex. PMID:20512368

  7. Acquisition, Analyses and Interpretation of fMRI Data: A Study on the Effective Connectivity in Human Primary Auditory Cortices

    International Nuclear Information System (INIS)

    A study on the effective connectivity characteristics in auditory cortices was conducted on five healthy Malay male subjects with the age of 20 to 40 years old using functional magnetic resonance imaging (fMRI), statistical parametric mapping (SPM5) and dynamic causal modelling (DCM). A silent imaging paradigm was used to reduce the scanner sound artefacts on functional images. The subjects were instructed to pay attention to the white noise stimulus binaurally given at intensity level of 70 dB higher than the hearing level for normal people. Functional specialisation was studied using Matlab-based SPM5 software by means of fixed effects (FFX), random effects (RFX) and conjunction analyses. Individual analyses on all subjects indicate asymmetrical bilateral activation between the left and right auditory cortices in Brodmann areas (BA)22, 41 and 42 involving the primary and secondary auditory cortices. The three auditory areas in the right and left auditory cortices are selected for the determination of the effective connectivity by constructing 9 network models. The effective connectivity is determined on four out of five subjects with the exception of one subject who has the BA22 coordinates located too far from BA22 coordinates obtained from group analysis. DCM results showed the existence of effective connectivity between the three selected auditory areas in both auditory cortices. In the right auditory cortex, BA42 is identified as input centre with unidirectional parallel effective connectivities of BA42→BA41and BA42→BA22. However, for the left auditory cortex, the input is BA41 with unidirectional parallel effective connectivities of BA41→BA42 and BA41→BA22. The connectivity between the activated auditory areas suggests the existence of signal pathway in the auditory cortices even when the subject is listening to noise. (author)

  8. 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

  9. Impact of morphometry, myelinization and synaptic current strength on spike conduction in human and cat spiral ganglion neurons.

    Directory of Open Access Journals (Sweden)

    Frank Rattay

    Full Text Available BACKGROUND: Our knowledge about the neural code in the auditory nerve is based to a large extent on experiments on cats. Several anatomical differences between auditory neurons in human and cat are expected to lead to functional differences in speed and safety of spike conduction. METHODOLOGY/PRINCIPAL FINDINGS: Confocal microscopy was used to systematically evaluate peripheral and central process diameters, commonness of myelination and morphology of spiral ganglion neurons (SGNs along the cochlea of three human and three cats. Based on these morphometric data, model analysis reveales that spike conduction in SGNs is characterized by four phases: a postsynaptic delay, constant velocity in the peripheral process, a presomatic delay and constant velocity in the central process. The majority of SGNs are type I, connecting the inner hair cells with the brainstem. In contrast to those of humans, type I neurons of the cat are entirely myelinated. Biophysical model evaluation showed delayed and weak spikes in the human soma region as a consequence of a lack of myelin. The simulated spike conduction times are in accordance with normal interwave latencies from auditory brainstem response recordings from man and cat. Simulated 400 pA postsynaptic currents from inner hair cell ribbon synapses were 15 times above threshold. They enforced quick and synchronous spiking. Both of these properties were not present in type II cells as they receive fewer and much weaker (∼26 pA synaptic stimuli. CONCLUSIONS/SIGNIFICANCE: Wasting synaptic energy boosts spike initiation, which guarantees the rapid transmission of temporal fine structure of auditory signals. However, a lack of myelin in the soma regions of human type I neurons causes a large delay in spike conduction in comparison with cat neurons. The absent myelin, in combination with a longer peripheral process, causes quantitative differences of temporal parameters in the electrically stimulated human cochlea

  10. Short- and long-term habituation of auditory event-related potentials in the rat [v1; ref status: indexed, http://f1000r.es/1l3

    Directory of Open Access Journals (Sweden)

    Kestutis Gurevicius

    2013-09-01

    Full Text Available An auditory oddball paradigm in humans generates a long-duration cortical negative potential, often referred to as mismatch negativity. Similar negativity has been documented in monkeys and cats, but it is controversial whether mismatch negativity also exists in awake rodents. To this end, we recorded cortical and hippocampal evoked responses in rats during alert immobility under a typical passive oddball paradigm that yields mismatch negativity in humans. The standard stimulus was a 9 kHz tone and the deviant either 7 or 11 kHz tone in the first condition. We found no evidence of a sustained potential shift when comparing evoked responses to standard and deviant stimuli. Instead, we found repetition-induced attenuation of the P60 component of the combined evoked response in the cortex, but not in the hippocampus. The attenuation extended over three days of recording and disappeared after 20 intervening days of rest. Reversal of the standard and deviant tones resulted is a robust enhancement of the N40 component not only in the cortex but also in the hippocampus. Responses to standard and deviant stimuli were affected similarly. Finally, we tested the effect of scopolamine in this paradigm. Scopolamine attenuated cortical N40 and P60 as well as hippocampal P60 components, but had no specific effect on the deviant response. We conclude that in an oddball paradigm the rat demonstrates repetition-induced attenuation of mid-latency responses, which resembles attenuation of the N1-component of human auditory evoked potential, but no mismatch negativity.

  11. Prostatic carcinoma in two cats

    International Nuclear Information System (INIS)

    Clinical, radiological and pathological features of two cats with prostatic carcinoma are reported. In both cats the presenting history included signs of lower urinary tract disease with haematuria and dysuria. Prostatomegaly was visible radiographically in one cat; an irregular intraprostatic urethra was seen on retrograde contrast urethrography in both cats. In one of the cats, neoplasia was suspected on the basis of a transurethral catheter biopsy. Following a poor response to palliative treatment in both cases, euthanasia was performed with histological confirmation of the diagnosis

  12. The Cat nRules

    CERN Document Server

    Mould, R A

    2004-01-01

    The nRules that are developed in another paper are applied to two versions of the Schrodinger cat experiment. In version I the initially conscious cat is made unconscious by a mechanism that is initiated by a radioactive decay. In version II the initially unconscious cat is awakened by a mechanism that is initiated by a radioactive decay. In both cases an observer is permitted to check the statues of the cat at any time during the experiment. In all cases the nRules correctly and unambiguously predict the conscious experience of the cat and the observer. Keywords: brain states of observer, stochastic choice, state reduction, wave collapse.

  13. 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)

  14. Effects of parietal TMS on visual and auditory processing at the primary cortical level -- a concurrent TMS-fMRI study

    DEFF Research Database (Denmark)

    Leitão, Joana; Thielscher, Axel; Werner, Sebastian; Pohmann, Rolf; Noppeney, Uta

    2013-01-01

    inputs (and vice versa). This concurrent transcranial magnetic stimulation-functional magnetic resonance imaging (TMS-fMRI) study applied repetitive TMS trains at no, low, and high intensity over right intraparietal sulcus (IPS) and vertex to investigate top-down influences on visual and auditory...... cortices under 3 sensory contexts: visual, auditory, and no stimulation. IPS-TMS increased activations in auditory cortices irrespective of sensory context as a result of direct and nonspecific auditory TMS side effects. In contrast, IPS-TMS modulated activations in the visual cortex in a state......-dependent fashion: it deactivated the visual cortex under no and auditory stimulation but amplified the BOLD response to visual stimulation. However, only the response amplification to visual stimulation was selective for IPS-TMS, while the deactivations observed for IPS- and Vertex-TMS resulted from crossmodal...

  15. 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.

  16. Genetic testing in domestic cats.

    Science.gov (United States)

    Lyons, Leslie A

    2012-12-01

    Varieties of genetic tests are currently available for the domestic cat that support veterinary health care, breed management, species identification, and forensic investigations. Approximately thirty-five genes contain over fifty mutations that cause feline health problems or alterations in the cat's appearance. Specific genes, such as sweet and drug receptors, have been knocked-out of Felidae during evolution and can be used along with mtDNA markers for species identification. Both STR and SNP panels differentiate cat race, breed, and individual identity, as well as gender-specific markers to determine sex of an individual. Cat genetic tests are common offerings for commercial laboratories, allowing both the veterinary clinician and the private owner to obtain DNA test results. This article will review the genetic tests for the domestic cat, and their various applications in different fields of science. Highlighted are genetic tests specific to the individual cat, which are a part of the cat's genome. PMID:22546621

  17. Positron Emission Tomography Imaging Reveals Auditory and Frontal Cortical Regions Involved with Speech Perception and Loudness Adaptation.

    Directory of Open Access Journals (Sweden)

    Georg Berding

    Full Text Available Considerable progress has been made in the treatment of hearing loss with auditory implants. However, there are still many implanted patients that experience hearing deficiencies, such as limited speech understanding or vanishing perception with continuous stimulation (i.e., abnormal loudness adaptation. The present study aims to identify specific patterns of cerebral cortex activity involved with such deficiencies. We performed O-15-water positron emission tomography (PET in patients implanted with electrodes within the cochlea, brainstem, or midbrain to investigate the pattern of cortical activation in response to speech or continuous multi-tone stimuli directly inputted into the implant processor that then delivered electrical patterns through those electrodes. Statistical parametric mapping was performed on a single subject basis. Better speech understanding was correlated with a larger extent of bilateral auditory cortex activation. In contrast to speech, the continuous multi-tone stimulus elicited mainly unilateral auditory cortical activity in which greater loudness adaptation corresponded to weaker activation and even deactivation. Interestingly, greater loudness adaptation was correlated with stronger activity within the ventral prefrontal cortex, which could be up-regulated to suppress the irrelevant or aberrant signals into the auditory cortex. The ability to detect these specific cortical patterns and differences across patients and stimuli demonstrates the potential for using PET to diagnose auditory function or dysfunction in implant patients, which in turn could guide the development of appropriate stimulation strategies for improving hearing rehabilitation. Beyond hearing restoration, our study also reveals a potential role of the frontal cortex in suppressing irrelevant or aberrant activity within the auditory cortex, and thus may be relevant for understanding and treating tinnitus.

  18. Positron Emission Tomography Imaging Reveals Auditory and Frontal Cortical Regions Involved with Speech Perception and Loudness Adaptation.

    Science.gov (United States)

    Berding, Georg; Wilke, Florian; Rode, Thilo; Haense, Cathleen; Joseph, Gert; Meyer, Geerd J; Mamach, Martin; Lenarz, Minoo; Geworski, Lilli; Bengel, Frank M; Lenarz, Thomas; Lim, Hubert H

    2015-01-01

    Considerable progress has been made in the treatment of hearing loss with auditory implants. However, there are still many implanted patients that experience hearing deficiencies, such as limited speech understanding or vanishing perception with continuous stimulation (i.e., abnormal loudness adaptation). The present study aims to identify specific patterns of cerebral cortex activity involved with such deficiencies. We performed O-15-water positron emission tomography (PET) in patients implanted with electrodes within the cochlea, brainstem, or midbrain to investigate the pattern of cortical activation in response to speech or continuous multi-tone stimuli directly inputted into the implant processor that then delivered electrical patterns through those electrodes. Statistical parametric mapping was performed on a single subject basis. Better speech understanding was correlated with a larger extent of bilateral auditory cortex activation. In contrast to speech, the continuous multi-tone stimulus elicited mainly unilateral auditory cortical activity in which greater loudness adaptation corresponded to weaker activation and even deactivation. Interestingly, greater loudness adaptation was correlated with stronger activity within the ventral prefrontal cortex, which could be up-regulated to suppress the irrelevant or aberrant signals into the auditory cortex. The ability to detect these specific cortical patterns and differences across patients and stimuli demonstrates the potential for using PET to diagnose auditory function or dysfunction in implant patients, which in turn could guide the development of appropriate stimulation strategies for improving hearing rehabilitation. Beyond hearing restoration, our study also reveals a potential role of the frontal cortex in suppressing irrelevant or aberrant activity within the auditory cortex, and thus may be relevant for understanding and treating tinnitus. PMID:26046763

  19. 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

  20. The cat is out of the bag

    KAUST Repository

    Ananthanarayanan, Rajagopal

    2009-01-01

    In the quest for cognitive computing, we have built a massively parallel cortical simulator, C2, that incorporates a number of innovations in computation, memory, and communication. Using C2 on LLNL\\'s Dawn Blue Gene/P supercomputer with 147, 456 CPUs and 144 TB of main memory, we report two cortical simulations - at unprecedented scale - that effectively saturate the entire memory capacity and refresh it at least every simulated second. The first simulation consists of 1.6 billion neurons and 8.87 trillion synapses with experimentally-measured gray matter thalamocortical connectivity. The second simulation has 900 million neurons and 9 trillion synapses with probabilistic connectivity. We demonstrate nearly perfect weak scaling and attractive strong scaling. The simulations, which incorporate phenomenological spiking neurons, individual learning synapses, axonal delays, and dynamic synaptic channels, exceed the scale of the cat cortex, marking the dawn of a new era in the scale of cortical simulations. Copyright 2009 ACM.

  1. The Cheshire Cat revisited

    CERN Document Server

    Vento, V

    1998-01-01

    The concept of effective field theory leads in a natural way to a construction principle for phenomenological sensible models known under the name of the Cheshire Cat Principle. We review its formulation in the chiral bag scenario and discuss its realization for the flavor singlet axial charge. Quantum effects inside the chiral bag induce a color anomaly which requires a compensating surface term to prevent breakdown of color gauge invariance. The presence of this surface term allows one to derive in a gauge-invariant way a chiral-bag version of the Shore-Veneziano two-component formula for the flavor-singlet axial charge of the proton. We show that one can obtain a striking Cheshire-Cat phenomenon with a negligibly small singlet axial charge.

  2. Sensory experience modifies feature map relationships in visual cortex.

    Science.gov (United States)

    Cloherty, Shaun L; Hughes, Nicholas J; Hietanen, Markus A; Bhagavatula, Partha S; Goodhill, Geoffrey J; Ibbotson, Michael R

    2016-01-01

    The extent to which brain structure is influenced by sensory input during development is a critical but controversial question. A paradigmatic system for studying this is the mammalian visual cortex. Maps of orientation preference (OP) and ocular dominance (OD) in the primary visual cortex of ferrets, cats and monkeys can be individually changed by altered visual input. However, the spatial relationship between OP and OD maps has appeared immutable. Using a computational model we predicted that biasing the visual input to orthogonal orientation in the two eyes should cause a shift of OP pinwheels towards the border of OD columns. We then confirmed this prediction by rearing cats wearing orthogonally oriented cylindrical lenses over each eye. Thus, the spatial relationship between OP and OD maps can be modified by visual experience, revealing a previously unknown degree of brain plasticity in response to sensory input. PMID:27310531

  3. Sensory experience modifies feature map relationships in visual cortex

    Science.gov (United States)

    Cloherty, Shaun L; Hughes, Nicholas J; Hietanen, Markus A; Bhagavatula, Partha S

    2016-01-01

    The extent to which brain structure is influenced by sensory input during development is a critical but controversial question. A paradigmatic system for studying this is the mammalian visual cortex. Maps of orientation preference (OP) and ocular dominance (OD) in the primary visual cortex of ferrets, cats and monkeys can be individually changed by altered visual input. However, the spatial relationship between OP and OD maps has appeared immutable. Using a computational model we predicted that biasing the visual input to orthogonal orientation in the two eyes should cause a shift of OP pinwheels towards the border of OD columns. We then confirmed this prediction by rearing cats wearing orthogonally oriented cylindrical lenses over each eye. Thus, the spatial relationship between OP and OD maps can be modified by visual experience, revealing a previously unknown degree of brain plasticity in response to sensory input. DOI: http://dx.doi.org/10.7554/eLife.13911.001 PMID:27310531

  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 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

  6. The orbitofrontal cortex and beyond: from affect to decision-making.

    Science.gov (United States)

    Rolls, Edmund T; Grabenhorst, Fabian

    2008-11-01

    The orbitofrontal cortex represents the reward or affective value of primary reinforcers including taste, touch, texture, and face expression. It learns to associate other stimuli with these to produce representations of the expected reward value for visual, auditory, and abstract stimuli including monetary reward value. The orbitofrontal cortex thus plays a key role in emotion, by representing the goals for action. The learning process is stimulus-reinforcer association learning. Negative reward prediction error neurons are related to this affective learning. Activations in the orbitofrontal cortex correlate with the subjective emotional experience of affective stimuli, and damage to the orbitofrontal cortex impairs emotion-related learning, emotional behaviour, and subjective affective state. With an origin from beyond the orbitofrontal cortex, top-down attention to affect modulates orbitofrontal cortex representations, and attention to intensity modulates representations in earlier cortical areas of the physical properties of stimuli. Top-down word-level cognitive inputs can bias affective representations in the orbitofrontal cortex, providing a mechanism for cognition to influence emotion. Whereas the orbitofrontal cortex provides a representation of reward or affective value on a continuous scale, areas beyond the orbitofrontal cortex such as the medial prefrontal cortex area 10 are involved in binary decision-making when a choice must be made. For this decision-making, the orbitofrontal cortex provides a representation of each specific reward in a common currency. PMID:18824074

  7. 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.

  8. Orientation-tuned surround suppression in mouse visual cortex

    OpenAIRE

    Self, Matthew W.; Lorteije, Jeannette A. M.; Vangeneugden, Joris; van Beest, Enny H; Grigore, Mihaela E; Levelt, Christiaan N.; Heimel, J.A.; Roelfsema, Pieter R.

    2014-01-01

    The firing rates of neurons in primary visual cortex (V1) are suppressed by large stimuli, an effect known as surround suppression. In cats and monkeys, the strength of suppression is sensitive to orientation; responses to regions containing uniform orientations are more suppressed than those containing orientation contrast. This effect is thought to be important for scene segmentation, but the underlying neural mechanisms are poorly understood. We asked whether it is possible to study these ...

  9. Adaptive filtering enhances information transmission in visual cortex

    OpenAIRE

    Sharpee, Tatyana O.; Sugihara, Hiroki; Kurgansky, Andrei V.; Rebrik, Sergei P.; Stryker, Michael P.; Miller, Kenneth D.

    2006-01-01

    Sensory neuroscience seeks to understand how the brain encodes natural environments. However, neural coding has largely been studied using simplified stimuli. In order to assess whether the brain’s coding strategy depends on the stimulus ensemble, we apply a new information-theoretic method that allows unbiased calculation of neural filters (receptive fields) from responses to natural scenes or other complex signals with strong multipoint correlations. In the cat primary visual cortex we comp...

  10. Source localization of auditory evoked potentials after cochlear implantation.

    Science.gov (United States)

    Debener, Stefan; Hine, Jemma; Bleeck, Stefan; Eyles, Julie

    2008-01-01

    Little is known about how the auditory cortex adapts to artificial input as provided by a cochlear implant (CI). We report the case of a 71-year-old profoundly deaf man, who has successfully used a unilateral CI for 4 years. Independent component analysis (ICA) of 61-channel EEG recordings could separate CI-related artifacts from auditory-evoked potentials (AEPs), even though it was the perfectly time-locked CI stimulation that caused the AEPs. AEP dipole source localization revealed contralaterally larger amplitudes in the P1-N1 range, similar to normal hearing individuals. In contrast to normal hearing individuals, the man with the CI showed a 20-ms shorter N1 latency ipsilaterally. We conclude that ICA allows the detailed study of AEPs in CI users. PMID:17910729

  11. 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

  12. 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.

  13. Local cloning of CAT states

    International Nuclear Information System (INIS)

    In this Letter we analyze the (im)possibility of the exact cloning of orthogonal three-qubit CAT states under local operation and classical communication (LOCC) with the help of a restricted entangled state. We also classify the three-qubit CAT states that can (not) be cloned under LOCC restrictions and extend the results to the n-qubit case. -- Highlights: → We analyze the (im)possibility of exact cloning of orthogonal CAT states under LOCC. → We also classify the set of CAT states that can(not) be cloned by LOCC. → No set of orthogonal CAT states can be cloned by LOCC with help of similar CAT state. → Any two orthogonal n-qubit GHZ-states can be cloned by LOCC with help of a GHZ state.

  14. Persistent Angiogenesis in the Autism Brain: An Immunocytochemical Study of Postmortem Cortex, Brainstem and Cerebellum

    Science.gov (United States)

    Azmitia, E. C.; Saccomano, Z. T.; Alzoobaee, M. F.; Boldrini, M.; Whitaker-Azmitia, P. M.

    2016-01-01

    In the current work, we conducted an immunocytochemical search for markers of ongoing neurogenesis (e.g. nestin) in auditory cortex from postmortem sections of autism spectrum disorder (ASD) and age-matched control donors. We found nestin labeling in cells of the vascular system, indicating blood vessels plasticity. Evidence of angiogenesis was…

  15. 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

  16. Environmental Enrichment for Indoor Cats

    OpenAIRE

    Herron, Meghan E.; Buffington, C. A. Tony

    2010-01-01

    Recommendations to cat owners to house their cats indoors confer the responsibility to provide conditions that ensure good health and welfare. Cats maintain their natural behaviors, such as scratching, chewing, and elimination, while living indoors, and they may develop health and behavior problems when deprived of appropriate environmental outlets for these behaviors. This article divides the environment into five basic “systems” to enable identification of features that may benefit from imp...

  17. Hypereosinophilic syndrome in two cats.

    Science.gov (United States)

    Takeuchi, Yoshinori; Matsuura, Shinobu; Fujino, Yasuhito; Nakajima, Mayumi; Takahashi, Masashi; Nakashima, Ko; Sakai, Yusuke; Uetsuka, Koji; Ohno, Koichi; Nakayama, Hiroyuki; Tsujimoto, Hajime

    2008-10-01

    Two cats showing chronic vomiting, diarrhea and weight loss were found to have leukocytosis with marked eosinophilia. Both cats were diagnosed with hypereosinophilic syndrome by the findings of increased eosinophils and their precursors in the bone marrow, eosinophilic infiltration into multiple organs, and exclusion of other causes for eosinophilia. Although cytoreductive chemotherapy with hydroxycarbamide and prednisolone was performed, these two cats died 48 days and 91 days after the initial presentation. PMID:18981665

  18. Environmental enrichment for indoor cats.

    Science.gov (United States)

    Herron, Meghan E; Buffington, C A Tony

    2010-12-01

    Recommendations to cat owners to house their cats indoors confer the responsibility to provide conditions that ensure good health and welfare. Cats maintain their natural behaviors, such as scratching, chewing, and elimination, while living indoors, and they may develop health and behavior problems when deprived of appropriate environmental outlets for these behaviors. This article divides the environment into five basic "systems" to enable identification of features that may benefit from improvement. It also addresses practical means of meeting cats' needs in each of these systems. PMID:21882164

  19. The Cat nRules

    OpenAIRE

    Mould, Richard A

    2004-01-01

    The nRules that are developed in another paper are applied to two versions of the Schrodinger cat experiment. In version I the initially conscious cat is made unconscious by a mechanism that is initiated by a radioactive decay. In version II the initially unconscious cat is awakened by a mechanism that is initiated by a radioactive decay. In both cases an observer is permitted to check the statues of the cat at any time during the experiment. In all cases the nRules correctly and unambiguousl...

  20. Functional and effective connectivity in an fMRI study of an auditory-related task.

    Science.gov (United States)

    Caclin, Anne; Fonlupt, Pierre

    2006-05-01

    This study investigates the sets of brain areas that are functionally connected during an auditory goal-directed task. We used a paradigm including a resting state condition and an active condition, which consisted in active listening to the footsteps of walking humans. The regional brain activity was measured using fMRI and the adjusted values of activity in brain regions involved in the task were analysed using both principal component analysis and structural equation modelling. A first set of connected areas includes regions located in Heschl's gyrus, planum temporale, posterior superior temporal sulcus (in the so-called 'social cognition' area), and parietal lobe. This network could be responsible for the perceptual integration of the auditory signal. A second set encompassing frontal regions is related to attentional control. Dorsolateral- and medial-prefrontal cortex have mutual negative influences which are similar to those described during a visual goal-directed task [T. Chaminade & P. Fonlupt (2003) Eur. J. Neurosci., 18, 675-679.]. Moreover, the dorsolateral prefrontal cortex (DLPFC) exerts a positive influence on the auditory areas during the task, as well as a strong negative influence on the visual areas. These results show that: (i) the negative influence between the medial and lateral parts of the frontal cortex during a goal-directed task is not dependent on the input modality (visual or auditory), and (ii) the DLPFC activates the pathway of the relevant sensory modality and inhibits the nonrelevant sensory modality pathway. PMID:16706860

  1. 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...

  2. Music training relates to the development of neural mechanisms of selective auditory attention.

    Science.gov (United States)

    Strait, Dana L; Slater, Jessica; O'Connell, Samantha; Kraus, Nina

    2015-04-01

    Selective attention decreases trial-to-trial variability in cortical auditory-evoked activity. This effect increases over the course of maturation, potentially reflecting the gradual development of selective attention and inhibitory control. Work in adults indicates that music training may alter the development of this neural response characteristic, especially over brain regions associated with executive control: in adult musicians, attention decreases variability in auditory-evoked responses recorded over prefrontal cortex to a greater extent than in nonmusicians. We aimed to determine whether this musician-associated effect emerges during childhood, when selective attention and inhibitory control are under development. We compared cortical auditory-evoked variability to attended and ignored speech streams in musicians and nonmusicians across three age groups: preschoolers, school-aged children and young adults. Results reveal that childhood music training is associated with reduced auditory-evoked response variability recorded over prefrontal cortex during selective auditory attention in school-aged child and adult musicians. Preschoolers, on the other hand, demonstrate no impact of selective attention on cortical response variability and no musician distinctions. This finding is consistent with the gradual emergence of attention during this period and may suggest no pre-existing differences in this attention-related cortical metric between children who undergo music training and those who do not. PMID:25660985

  3. Music training relates to the development of neural mechanisms of selective auditory attention

    Directory of Open Access Journals (Sweden)

    Dana L. Strait

    2015-04-01

    Full Text Available Selective attention decreases trial-to-trial variability in cortical auditory-evoked activity. This effect increases over the course of maturation, potentially reflecting the gradual development of selective attention and inhibitory control. Work in adults indicates that music training may alter the development of this neural response characteristic, especially over brain regions associated with executive control: in adult musicians, attention decreases variability in auditory-evoked responses recorded over prefrontal cortex to a greater extent than in nonmusicians. We aimed to determine whether this musician-associated effect emerges during childhood, when selective attention and inhibitory control are under development. We compared cortical auditory-evoked variability to attended and ignored speech streams in musicians and nonmusicians across three age groups: preschoolers, school-aged children and young adults. Results reveal that childhood music training is associated with reduced auditory-evoked response variability recorded over prefrontal cortex during selective auditory attention in school-aged child and adult musicians. Preschoolers, on the other hand, demonstrate no impact of selective attention on cortical response variability and no musician distinctions. This finding is consistent with the gradual emergence of attention during this period and may suggest no pre-existing differences in this attention-related cortical metric between children who undergo music training and those who do not.

  4. Flexibility and Stability in Sensory Processing Revealed Using Visual-to-Auditory Sensory Substitution.

    Science.gov (United States)

    Hertz, Uri; Amedi, Amir

    2015-08-01

    The classical view of sensory processing involves independent processing in sensory cortices and multisensory integration in associative areas. This hierarchical structure has been challenged by evidence of multisensory responses in sensory areas, and dynamic weighting of sensory inputs in associative areas, thus far reported independently. Here, we used a visual-to-auditory sensory substitution algorithm (SSA) to manipulate the information conveyed by sensory inputs while keeping the stimuli intact. During scan sessions before and after SSA learning, subjects were presented with visual images and auditory soundscapes. The findings reveal 2 dynamic processes. First, crossmodal attenuation of sensory cortices changed direction after SSA learning from visual attenuations of the auditory cortex to auditory attenuations of the visual cortex. Secondly, associative areas changed their sensory response profile from strongest response for visual to that for auditory. The interaction between these phenomena may play an important role in multisensory processing. Consistent features were also found in the sensory dominance in sensory areas and audiovisual convergence in associative area Middle Temporal Gyrus. These 2 factors allow for both stability and a fast, dynamic tuning of the system when required. PMID:24518756

  5. Evoked potentials in immobilized cats to a combination of clicks with painful electrocutaneous stimuli

    Science.gov (United States)

    Gilinskiy, M. A.; Korsakov, I. A.

    1979-01-01

    Averaged evoked potentials in the auditory, somatosensory, and motor cortical zones, as well as in the mesencephalic reticular formation were recorded in acute experiments on nonanesthetized, immobilized cats. Omission of the painful stimulus after a number of pairings resulted in the appearance of a delayed evoked potential, often resembling the late phases of the response to the painful stimulus. The characteristics of this response are discussed in comparison with conditioned changes of the sensory potential amplitudes.

  6. cats and dogs

    Institute of Scientific and Technical Information of China (English)

    颜玉秀

    2003-01-01

    有这样一则英语成语:“To rain cats anddogs.”如果望文生义,则会被译为“下猫下狗”,因而会弄出许多笑话来,这应当是值得引以为戒的。其实这句成语的真正含义是:“下倾盆大雨”。那么下雨为什么会与cats和dogs联系在一起呢?

  7. Altered cortical activity in prelingually deafened cochlear implant users following long periods of auditory deprivation.

    Science.gov (United States)

    Lammers, Marc J W; Versnel, Huib; van Zanten, Gijsbert A; Grolman, Wilko

    2015-02-01

    Auditory stimulation during childhood is critical for the development of the auditory cortex in humans and with that for hearing in adulthood. Age-related changes in morphology and peak latencies of the cortical auditory evoked potential (CAEP) have led to the use of this cortical response as a biomarker of auditory cortical maturation including studies of cortical development after deafness and subsequent cochlear implantation. To date, it is unknown whether prelingually deaf adults, with early onset deafness (before the age of 2 years) and who received a cochlear implant (CI) only during adulthood, would display absent or aberrant CAEP waveforms as predicted from CAEP studies in late implanted prelingually deaf children. In the current study, CAEP waveforms were recorded in response to electric stimuli in prelingually deaf adults, who received their CI after the age of 21 years. Waveform morphology and peak latencies were compared to the CAEP responses obtained in postlingually deaf adults, who became deaf after the age of 16. Unexpectedly, typical CAEP waveforms with adult-like P1-N1-P2 morphology could be recorded in the prelingually deaf adult CI users. On visual inspection, waveform morphology was comparable to the CAEP waveforms recorded in the postlingually deaf CI users. Interestingly, however, latencies of the N1 peak were significantly shorter and amplitudes were significantly larger in the prelingual group than in the postlingual group. The presence of the CAEP together with an early and large N1 peak might represent activation of the more innate and less complex components of the auditory cortex of the prelingually deaf CI user, whereas the CAEP in postlingually deaf CI users might reflect activation of the mature neural network still present in these patients. The CAEPs may therefore be helpful in the assessment of developmental state of the auditory cortex. PMID:25315357

  8. EzCatDB: M00143 [EzCatDB

    Lifescience Database Archive (English)

    Full Text Available http://ezcatdb.cbrc.jp/EzCatDB/search/get.do?dbcode=M00143 EzCatDB M00143 0) { response = "?" + ... 1995 Volume 34 Pages 955-64 Authors Mimeault M, De Lean ... A, Lafleur M, Bonenfant D, Fournier A Title Evalua ...

  9. Toxoplasmosis: An Important Message for Cat Owners

    Science.gov (United States)

    ... role do cats play in the spread of toxoplasmosis? Cats get Toxoplasma infection by eating infected rodents, ... an infected cat may have defecated. What is toxoplasmosis? Toxoplasmosis is an infection caused by a microscopic ...

  10. Prefrontal cortex based sex differences in tinnitus perception: same tinnitus intensity, same tinnitus distress, different mood.

    Directory of Open Access Journals (Sweden)

    Sven Vanneste

    Full Text Available BACKGROUND: Tinnitus refers to auditory phantom sensation. It is estimated that for 2% of the population this auditory phantom percept severely affects the quality of life, due to tinnitus related distress. Although the overall distress levels do not differ between sexes in tinnitus, females are more influenced by distress than males. Typically, pain, sleep, and depression are perceived as significantly more severe by female tinnitus patients. Studies on gender differences in emotional regulation indicate that females with high depressive symptoms show greater attention to emotion, and use less anti-rumination emotional repair strategies than males. METHODOLOGY: The objective of this study was to verify whether the activity and connectivity of the resting brain is different for male and female tinnitus patients using resting-state EEG. CONCLUSIONS: Females had a higher mean score than male tinnitus patients on the BDI-II. Female tinnitus patients differ from male tinnitus patients in the orbitofrontal cortex (OFC extending to the frontopolar cortex in beta1 and beta2. The OFC is important for emotional processing of sounds. Increased functional alpha connectivity is found between the OFC, insula, subgenual anterior cingulate (sgACC, parahippocampal (PHC areas and the auditory cortex in females. Our data suggest increased functional connectivity that binds tinnitus-related auditory cortex activity to auditory emotion-related areas via the PHC-sgACC connections resulting in a more depressive state even though the tinnitus intensity and tinnitus-related distress are not different from men. Comparing male tinnitus patients to a control group of males significant differences could be found for beta3 in the posterior cingulate cortex (PCC. The PCC might be related to cognitive and memory-related aspects of the tinnitus percept. Our results propose that sex influences in tinnitus research cannot be ignored and should be taken into account in functional

  11. Accelerator programme at CAT

    International Nuclear Information System (INIS)

    The Accelerator Programme at the Centre for Advanced Technology (CAT), Indore, has very broad based concept under which all types of accelerators are to be taken up for design and fabrication. This centre will be housing a wide variety of accelerators to serve as a common facility for the universities, national laboratories in addition to laboratories under the Department of Atomic Energy. In the first phase of the programme, a series of electron accelerators are designed and fabricated. They are synchrotron radiation sources of 450 MeV (INDUS-I) and of 2 GeV (INDUS-II), microtron upto energy of 20 MeV, linear accelerator upto 20 MeV, and DC Accelerator for industrial irradiation upto 750 KeV and 20 KW. A proton accelerator of 300 MeV with 20 MeV linac injector is also designed. CAT is also developing a strong base for support technologies like ultra high vacuum, radio frequency and microwaves, DC pulsed and superconducting magnets, power supplies and controls etc. These technologies are very useful for other industrial applications also. To develop user groups to utilise INDUS-II synchrotron radiation source, a batch production of rotating Anode X-ray generators with power supplies has been initiated. So also, the sputter ion pumps, electron guns, turbo molecular pumps are brought into batch production. (author)

  12. The Neurophysiology of Auditory Hallucinations – A Historic and Contemporary Review

    Directory of Open Access Journals (Sweden)

    Remko evan Lutterveld

    2011-05-01

    Full Text Available Electroencephalography (EEG and magnetoencephalography (MEG are two techniques that distinguish themselves from other neuroimaging methodologies through their ability to directly measure brain-related activity and their high temporal resolution. A large body of research has applied these techniques to study auditory hallucinations. Across a variety of approaches, the left superior temporal cortex is consistently reported to be involved in this symptom. Moreover, there is increasing evidence that a failure in corollary discharge, i.e. a neural signal originating in frontal speech areas that indicates to sensory areas that forthcoming thought is self-generated, may underlie the experience of auditory hallucinations

  13. Auditory Cortical Deactivation during Speech Production and following Speech Perception: An EEG investigation of the temporal dynamics of the auditory alpha rhythm

    OpenAIRE

    David E Jenson; Bowers, Andrew L.

    2015-01-01

    Sensorimotor integration within the dorsal stream enables online monitoring of speech. Jenson et al. (2014) used independent component analysis (ICA) and event related spectral perturbation (ERSP) analysis of EEG data to describe anterior sensorimotor (e.g., premotor cortex; PMC) activity during speech perception and production. The purpose of the current study was to identify and temporally map neural activity from posterior (i.e., auditory) regions of the dorsal stream in the same tasks. ...

  14. Auditory cortical deactivation during speech production and following speech perception: an EEG investigation of the temporal dynamics of the auditory alpha rhythm

    OpenAIRE

    Jenson, David; Harkrider, Ashley W.; Thornton, David; Bowers, Andrew L.; Saltuklaroglu, Tim

    2015-01-01

    Sensorimotor integration (SMI) across the dorsal stream enables online monitoring of speech. Jenson et al. (2014) used independent component analysis (ICA) and event related spectral perturbation (ERSP) analysis of electroencephalography (EEG) data to describe anterior sensorimotor (e.g., premotor cortex, PMC) activity during speech perception and production. The purpose of the current study was to identify and temporally map neural activity from posterior (i.e., auditory) regions of the dors...

  15. CONTRACT ADMINISTRATIVE TRACKING SYSTEM (CATS)

    Science.gov (United States)

    The Contract Administrative Tracking System (CATS) was developed in response to an ORD NHEERL, Mid-Continent Ecology Division (MED)-recognized need for an automated tracking and retrieval system for Cost Reimbursable Level of Effort (CR/LOE) Contracts. CATS is an Oracle-based app...

  16. College Students and Their Cats

    Science.gov (United States)

    Weinstein, Lawrence; Alexander, Ralph

    2010-01-01

    Twenty-two Siamese and 32 mixed breed cats' personalities were rated by their respective college student owners and compared. Further, the owners' self rated personality traits were correlated with the pets'; significant Siamese and Mixed differences and correlations were obtained. These are the first data to examine breed of cat on a personality…

  17. [Glomerulonephritis in dogs and cats].

    Science.gov (United States)

    Reinacher, M; Frese, K

    1991-04-01

    Immunohistology and special staining of plastic sections allow diagnosis and differentiation of subtypes of glomerulonephritis in dogs. Frequency and clinical importance of these forms of glomerulonephritis vary significantly. In cats, glomerulonephritis occurs frequently in FIV-positive cats but is rare in animals suffering from persistent FeLV infection or FIP. PMID:2068715

  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. 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

  20. 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...

  1. 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...

  2. Peritoneopericardial diaphragmatic hernia in cats

    International Nuclear Information System (INIS)

    Peritoneopericardial diaphragmatic hernia in a cat is often an incidental finding on a routine thoracic or abdominal radiograph. Clinical signs are nonspecific-usually respiratory (dyspnea) or gastrointestinal(vomiting or diarrhea). Some of the cats with this anomaly are asymptomatic. The physical examination may be normal: muffled heart sounds are the most common abnormality noted during a physical examination. Cats of many breeds are affected, although 26% of reported cases were inPersians. Age of the cat at diagnosis ranged from 6 days to 14 years. Thirty of the 52 reported cases were in females. Diagnostic studies used to confirm the diagnosis included echocardiography, upper gastrointestinal study, ultrasonography, angiography, positive-contrast peritoneography, and laparotomy. Surgical correction was reportedly successful in 22 of 25 cats

  3. 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...

  4. 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.

  5. Estimation of the synaptic input firing rates and characterization of the stimulation effects in an auditory neuron

    Czech Academy of Sciences Publication Activity Database

    Kobayashi, R.; He, J.; Lánský, Petr

    2015-01-01

    Roč. 9, May 18 (2015), s. 59. ISSN 1662-5188 R&D Projects: GA ČR(CZ) GA15-08066S Institutional support: RVO:67985823 Keywords : synaptic inputs * statistical inference * state-space models * intracellular recordings * auditory cortex Subject RIV: BD - Theory of Information Impact factor: 2.201, year: 2014

  6. There's no ball without noise: cats' prediction of an object from noise.

    Science.gov (United States)

    Takagi, Saho; Arahori, Minori; Chijiiwa, Hitomi; Tsuzuki, Mana; Hataji, Yuya; Fujita, Kazuo

    2016-09-01

    We used an expectancy violation procedure to ask whether cats could use a causal rule to infer the presence of an unseen object on hearing the noise it made inside a container and predict its appearance when the container was turned over. We presented cats with either an object dropping out of an opaque container or no object dropping out (turning-over phase) after producing either a rattling sound by shaking the container with the object inside, or no sound (shaking phase). The cats were then allowed to freely explore the experimental environment (exploration phase). The relation between the sound and the object matched with physical laws in half of the trials (congruent condition) and mismatched in the other half (incongruent condition). Inferring the presence of an unseen object from the noise was predicted to result in longer looking time in the incongruent condition. The prediction was supported by the cats' behavior during the turning-over phase. The results suggest that cats used a causal-logical understanding of auditory stimuli to predict the appearance of invisible objects. The ecology of cats' natural hunting style may favor the ability for inference on the basis of sounds. PMID:27299293

  7. 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 ...

  8. 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 ...

  9. Animal models of spontaneous activity in the healthy and impaired auditory system

    Directory of Open Access Journals (Sweden)

    Jos J Eggermont

    2015-04-01

    Full Text Available Spontaneous neural activity in the auditory nerve fibers and in auditory cortex in healthy animals is discussed with respect to the question: Is spontaneous activity noise or information carrier? The studies reviewed suggest strongly that spontaneous activity is a carrier of information. Subsequently, I review the numerous findings in the impaired auditory system, particularly with reference to noise trauma and tinnitus. Here the common assumption is that tinnitus reflects increased noise in the auditory system that among others affects temporal processing and interferes with the gap-startle reflex, which is frequently used as a behavioral assay for tinnitus. It is, however, more likely that the increased spontaneous activity in tinnitus, firing rate as well as neural synchrony, carries information that shapes the activity of downstream structures, including non-auditory ones, and leading to the tinnitus percept. The main drivers of that process are bursting and synchronous firing, which facilitates transfer of activity across synapses, and allows formation of auditory objects, such as tinnitus

  10. Response properties of cat AMLS neurons to optic flow stimuli

    Institute of Scientific and Technical Information of China (English)

    LI; Baowang(李宝旺); LI; Bing(李兵); CHEN; Hui(陈辉); XU; Ying(徐颖); DIAO; Yuncheng(刁云程)

    2002-01-01

    Spiral and translation stimuli were used to investigate the response properties of cat AMLS (anteromedial lateral suprasylvian area) neurons to optic flow. The overwhelming majority of cells could be significantly excited by the two modes of stimuli and most responsive cells displayed obvious direction selectivity. It is the first time to find a visual area in mammalian brain preferring rotation stimuli. Two representative hypotheses are discussed here on the neural mechanism of optic flow analysis in visual cortex, and some new viewpoints are proposed to explain the experimental results.

  11. Like herding cats.

    Science.gov (United States)

    Muller-Smith, P

    1997-12-01

    In an effort to be a good manager, it is easy to lose sight of the fact that knowledge workers require a unique approach from their manager. Because nurses are independent and capable individuals that prosper in an environment that recognizes them as knowledge workers, nurse managers often find that traditional management techniques are not sufficient. Trying to manage all of the nurses on a unit as a single group is much like trying to herd cats. It might be less frustrating for the nurse manager to lead gently rather than manage with a firm hand. Warren Bennis suggests that this approach may provide a valuable key to successfully managing in a world of constant change. PMID:9464034

  12. Cat Ownership Perception and Caretaking Explored in an Internet Survey of People Associated with Cats

    OpenAIRE

    Zito, Sarah; Vankan, Dianne; Bennett, Pauleen; Paterson, Mandy; Phillips, Clive J. C.

    2015-01-01

    People who feed cats that they do not perceive they own (sometimes called semi-owners) are thought to make a considerable contribution to unwanted cat numbers because the cats they support are generally not sterilized. Understanding people’s perception of cat ownership and the psychology underlying cat semi-ownership could inform approaches to mitigate the negative effects of cat semi-ownership. The primary aims of this study were to investigate cat ownership perception and to examine its ass...

  13. Enhancement and distortion in the temporal representation of sounds in the ventral cochlear nucleus of chinchillas and cats.

    Directory of Open Access Journals (Sweden)

    Alberto Recio-Spinoso

    Full Text Available A subset of neurons in the cochlear nucleus (CN of the auditory brainstem has the ability to enhance the auditory nerve's temporal representation of stimulating sounds. These neurons reside in the ventral region of the CN (VCN and are usually known as highly synchronized, or high-sync, neurons. Most published reports about the existence and properties of high-sync neurons are based on recordings performed on a VCN output tract--not the VCN itself--of cats. In other species, comprehensive studies detailing the properties of high-sync neurons, or even acknowledging their existence, are missing.Examination of the responses of a population of VCN neurons in chinchillas revealed that a subset of those neurons have temporal properties similar to high-sync neurons in the cat. Phase locking and entrainment--the ability of a neuron to fire action potentials at a certain stimulus phase and at almost every stimulus period, respectively--have similar maximum values in cats and chinchillas. Ranges of characteristic frequencies for high-sync neurons in chinchillas and cats extend up to 600 and 1000 Hz, respectively. Enhancement of temporal processing relative to auditory nerve fibers (ANFs, which has been shown previously in cats using tonal and white-noise stimuli, is also demonstrated here in the responses of VCN neurons to synthetic and spoken vowel sounds.Along with the large amount of phase locking displayed by some VCN neurons there occurs a deterioration in the spectral representation of the stimuli (tones or vowels. High-sync neurons exhibit a greater distortion in their responses to tones or vowels than do other types of VCN neurons and auditory nerve fibers.Standard deviations of first-spike latency measured in responses of high-sync neurons are lower than similar values measured in ANFs' responses. This might indicate a role of high-sync neurons in other tasks beyond sound localization.

  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. Short colon in a cat

    International Nuclear Information System (INIS)

    An 11-year-old male Japanese domestic cat was referred to the veterinary hospital with a chronic diarrhea and signs of pain and vocalization when defecating. The cat has discharged unformed feces throughout his life. Morphological diagnosis of short colon was made radiographically after barium enema. The ileocolic junction and cecum was located to the left of the midline at the proximal end of the descending colon. Additional endoscopic examination demonstrated the difference in visual structures of the mucosal surface and in histological structures on mucosal biopsy specimens, between the colon and ileum. This is the first report of short colon in a cat in Japan

  16. 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

  17. Fundamentals of ServCat

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This training manual for the U.S. Fish and Wildlife Service Catalog (ServCat) provides detailed instructions on searching for records, creating records, and...

  18. NRPC ServCat priorities

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document lists the Natural Resource Program Centers priority ServCat documents. It is recommended that these documents which include annual narrative reports,...

  19. Localized Brain Activation Related to the Strength of Auditory Learning in a Parrot

    OpenAIRE

    Hiroko Eda-Fujiwara; Takuya Imagawa; Masanori Matsushita; Yasushi Matsuda; Hiro-Aki Takeuchi; Ryohei Satoh; Aiko Watanabe; Zandbergen, Matthijs A.; Kazuchika Manabe; Takashi Kawashima; Johan J Bolhuis

    2012-01-01

    Parrots and songbirds learn their vocalizations from a conspecific tutor, much like human infants acquire spoken language. Parrots can learn human words and it has been suggested that they can use them to communicate with humans. The caudomedial pallium in the parrot brain is homologous with that of songbirds, and analogous to the human auditory association cortex, involved in speech processing. Here we investigated neuronal activation, measured as expression of the protein product of the imm...

  20. 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

  1. Spectrotemporal processing differences between auditory cortical fast-spiking and regular-spiking neurons

    OpenAIRE

    Atencio, Craig A.; Schreiner, Christoph E

    2008-01-01

    Excitatory pyramidal neurons and inhibitory interneurons constitute the main elements of cortical circuitry and have distinctive morphologic and electrophysiological properties. Here, we differentiate them by analyzing the time course of their action potentials (APs) and characterizing their receptive field properties in auditory cortex. Pyramidal neurons have longer APs and discharge as Regular-Spiking Units (RSUs), while basket and chandelier cells, which are inhibitory interneurons, have s...

  2. Effect of stimulation of trigeminal ganglion on regional cerebral blood flow in cats

    International Nuclear Information System (INIS)

    Regional cerebral blood flow was studied in the cat, with and without trigeminal ganglion stimulation, by the intravenous injection of the tracer [14C]iodoantipyrine and subsequent regional brain dissection. Electrical activation of the trigeminal ganglion led to a selective increase in regional blood flow in the frontal and parietal cortex that was bilateral without change in the posterior cortex, deep cerebral nuclei, white matter, or brain stem. Unilateral intracranial section of the facial nerve blocked the response in the ipsilateral frontal and parietal cortex, whereas bilateral facial nerve section blocked the contralateral frontal cortical response. The contralateral parietal cortical increase in blood flow was not affected by facial nerve section and may thus represent the result of metabolic activation of sensory cortex

  3. Properties of squeezed Schroedinger cats

    International Nuclear Information System (INIS)

    In this article we investigate some statistical properties of the even and odd squeezed (squeezed Schroedinger cat) states. The quasi-probability distribution functions especially W(α) and Q(α) are calculated and discussed for these states. The phase distribution function is discussed. A generation scheme is proposed for either the squeezed generalized Schroedinger cat, or the squeezed number state. (author). 35 refs, 5 figs

  4. Seizures and epilepsy in cats

    OpenAIRE

    Moore SA

    2014-01-01

    Sarah A Moore Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, OH, USA Abstract: Seizures are a common presenting complaint in cats, although causes and options for the treatment of seizures in this species have been historically poorly described in the veterinary literature. Seizure manifestation in cats may be different than what is typically seen in dogs, but the underlying causes of seizure activity are the same. These include primary epilepsies, structura...

  5. Echocardiographic Findings in 11 Cats with Acromegaly

    OpenAIRE

    Myers, J A; Lunn, K.F.; Bright, J.M.

    2014-01-01

    Background Information regarding cardiac changes in domestic cats with acromegaly is limited. Hypothesis/Objectives The objective of this study was to describe the echocardiographic findings in cats with acromegaly. Animals Eighteen cats diagnosed with acromegaly at Colorado State University between 2008 and 2012. Of these 18 cats, 11 had echocardiography performed. Methods A retrospective review of medical records was made to identify cats with acromegaly that also had echocardiography perfo...

  6. Schrodinger's cat: much ado about nothing

    CERN Document Server

    Ionicioiu, Radu

    2016-01-01

    In this note I briefly discuss the Schrodinger's cat Gedankenexperiment. By analysing the information flow in the system I show that no entanglement exists between the atom and the cat. The atom and the cat are connected only through a classical information channel (detector clicks $\\rightarrow$ poison is released $\\rightarrow$ cat is dead). No amount of local operations and classical communication can entangle the atom and the cat. Consequently, the paradox disappears.

  7. Acquired retinal folds in the cat.

    Science.gov (United States)

    MacMillan, A D

    1976-06-01

    Retinal folds were found in 5 cats. The apparent cause of the folding was varied: in 1 cat the folds appeared after a localized retinal detachment; in 2 cats the condition accompanied other intraocular abnormalities associated with feline infectious peritonitis; 1 cat had active keratitis, and the retinal changes were thought to have been injury related; and 1 cat, bilaterally affected, had chronic glomerulonephritis. PMID:945253

  8. 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

  9. Primary hypoadrenocorticism in ten cats.

    Science.gov (United States)

    Peterson, M E; Greco, D S; Orth, D N

    1989-01-01

    Primary hypoadrenocorticism was diagnosed in ten young to middle-aged cats of mixed breeding. Five of the cats were male, and five were female. Historic signs included lethargy (n = 10), anorexia (n = 10), weight loss (n = 9), vomiting (n = 4), and polyuria (n = 3). Dehydration (n = 9), hypothermia (n = 8), prolonged capillary refill time (n = 5), weak pulse (n = 5), collapse (n = 3), and sinus bradycardia (n = 2) were found on physical examination. Results of initial laboratory tests revealed anemia (n = 3), absolute lymphocytosis (n = 2), absolute eosinophilia (n = 1), and azotemia and hyperphosphatemia (n = 10). Serum electrolyte changes included hyponatremia (n = 10), hyperkalemia (n = 9), hypochloremia (n = 9), and hypercalcemia (n = 1). The diagnosis of primary adrenocortical insufficiency was established on the basis of results of adrenocorticotropic hormone (ACTH) stimulation tests (n = 10) and endogenous plasma ACTH determinations (n = 7). Initial therapy for hypoadrenocorticism included intravenous administration of 0.9% saline and dexamethasone and intramuscular administration of desoxycorticosterone acetate in oil. Three cats were euthanatized shortly after diagnosis because of poor clinical response. Results of necropsy examination were unremarkable except for complete destruction of both adrenal cortices. Seven cats were treated chronically with oral prednisone or intramuscular methylprednisolone acetate for glucocorticoid supplementation and with oral fludrocortisone acetate or intramuscular injections of repository desoxycorticosterone pivalate for mineralocorticoid replacement. One cat died after 47 days of therapy from unknown causes; the other six cats are still alive and well after 3 to 70 months of treatment. PMID:2469793

  10. Auditory fMRI of Sound Intensity and Loudness for Unilateral Stimulation.

    Science.gov (United States)

    Behler, Oliver; Uppenkamp, Stefan

    2016-01-01

    We report a systematic exploration of the interrelation of sound intensity, ear of entry, individual loudness judgments, and brain activity across hemispheres, using auditory functional magnetic resonance imaging (fMRI). The stimuli employed were 4 kHz-bandpass filtered noise stimuli, presented monaurally to each ear at levels from 37 to 97 dB SPL. One diotic condition and a silence condition were included as control conditions. Normal hearing listeners completed a categorical loudness scaling procedure with similar stimuli before auditory fMRI was performed. The relationship between brain activity, as inferred from blood oxygenation level dependent (BOLD) contrasts, and both sound intensity and loudness estimates were analyzed by means of linear mixed effects models for various anatomically defined regions of interest in the ascending auditory pathway and in the cortex. The results indicate distinct functional differences between midbrain and cortical areas as well as between specific regions within auditory cortex, suggesting a systematic hierarchy in terms of lateralization and the representation of sensory stimulation and perception. PMID:27080657

  11. 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

  12. Mesotelioma pleural com metástase renal em gato Pleural mesothelioma with renal metastasis in a cat

    Directory of Open Access Journals (Sweden)

    A.M. Piacenti

    2004-08-01

    Full Text Available It has been described the anatomopathological and immunohistochemical characteristics of a multinodular neoplasm distributed in the parietal and visceral pleurae, pericardium, thoracic portion of the diaphragm and renal cortex of an eight year-old, female, mixed breed, cat. Based on the anatomopathological and immunohistochemical findings it was firmed the diagnosis of biphasic pleural mesotelioma with renal metastasis.

  13. Regulating prefrontal cortex activation

    DEFF Research Database (Denmark)

    Aznar, Susana; Klein, Anders Bue

    2013-01-01

    The prefrontal cortex (PFC) is involved in mediating important higher-order cognitive processes such as decision making, prompting thereby our actions. At the same time, PFC activation is strongly influenced by emotional reactions through its functional interaction with the amygdala and the stria...

  14. 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.

  15. 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...

  16. Reported cat bites in Dallas: characteristics of the cats, the victims, and the attack events.

    OpenAIRE

    Wright, J C

    1990-01-01

    Associated with the increased popularity of cats as pets in American households has been an increase in the number of cat bites reported to health departments. Bite reports from Dallas, TX, for 1985 were analyzed for different aspects of the cat bite event, including characteristics of the cats, the people bitten, the wounds, and the attack events. Cat bites and scratches constituted 25 percent of the 2,494 reported animal bites. Biting cats were typically stray females. People 21 to 35 years...

  17. Cat Ownership Perception and Caretaking Explored in an Internet Survey of People Associated with Cats.

    Directory of Open Access Journals (Sweden)

    Sarah Zito

    Full Text Available People who feed cats that they do not perceive they own (sometimes called semi-owners are thought to make a considerable contribution to unwanted cat numbers because the cats they support are generally not sterilized. Understanding people's perception of cat ownership and the psychology underlying cat semi-ownership could inform approaches to mitigate the negative effects of cat semi-ownership. The primary aims of this study were to investigate cat ownership perception and to examine its association with human-cat interactions and caretaking behaviours. A secondary aim was to evaluate a definition of cat semi-ownership (including an association time of ≥1 month and frequent feeding, revised from a previous definition proposed in the literature to distinguish cat semi-ownership from casual interactions with unowned cats. Cat owners and semi-owners displayed similar types of interactions and caretaking behaviours. Nevertheless, caretaking behaviours were more commonly displayed towards owned cats than semi-owned cats, and semi-owned cats were more likely to have produced kittens (p<0.01. All interactions and caretaking behaviours were more likely to be displayed towards cats in semi-ownership relationships compared to casual interaction relationships. Determinants of cat ownership perception were identified (p<0.05 and included association time, attachment, perceived cat friendliness and health, and feelings about unowned cats, including the acceptability of feeding unowned cats. Encouraging semi-owners to have the cats they care for sterilized may assist in reducing the number of unwanted kittens and could be a valuable alternative to trying to prevent semi-ownership entirely. Highly accessible semi-owner "gatekeepers" could help to deliver education messages and facilitate the provision of cat sterilization services to semi-owners. This research enabled semi-ownership to be distinguished from casual interaction relationships and can assist

  18. Modeling auditory-nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

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

    2014-01-01

    Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electricaltransduction in the inner ear. Trains of biphasic, charge-balanced pulses (anodic and cathodic) areused as stimuli to avoid damage of the tissue. The pulses of either polarity are capable of producing...... andcathodic stimulation of the AN of cat [4]. The models' responses to the electrical pulses of variousshapes [5] were also analyzed. It was found that, while the models can account for the ring rates inresponse to various biphasic pulse shapes, they fail to correctly describe the timing of AP in response to...... monophasic pulses. Strategies for improving the model performance with respect to correct AP timing are discussed. Eventually, a model that is able to account for correct spike timing in electrichearing will be useful for objective evaluation and improvement of CI stimulation strategies....

  19. Utility of MR imaging in cat-scratch neuroretinitis

    International Nuclear Information System (INIS)

    About 80% of cat-scratch disease (CSD) infections occur in children, and CSD neuroretinitis (optic neuropathy with retinal exudates in a ''macular star'' pattern) mostly occurs in children and young adults. A recent study suggested that CSD optic neuropathy has specific features on MR imaging. However, MR imaging findings in CSD neuroretinitis are not well described in the pediatric literature. We present a patient with CSD neuroretinitis in whom these specific MR imaging features preceded the macular star, a funduscopic finding strongly suggestive of neuroretinitis. This case demonstrates how knowledge of these features is important in the appropriate diagnostic work-up of optic neuropathy. MR imaging also incidentally revealed neuritis of another cranial nerve in the auditory canal - a rare manifestation of CSD. (orig.)

  20. 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.

  1. Role of creatine in sensitivity and function of the auditory and vestibular system

    Directory of Open Access Journals (Sweden)

    Vahid Moradi

    2015-02-01

    Full Text Available Background and Aim: Creatine plays an important role in the regulation of cellular energy in high energy demand organs such as the inner ear. It is also believed to play a protective role. This article reviewed the mechanisms and effects of creatine on the auditory and vestibular systems.Recent Findings: Creatine transporters and creatine kinase enzymes are involved in converting creatine to creatine phosphate. Phosphate is a fuel cell available in the cochlear and vestibular hair cells and the protective cells, striavascularis, peripheral and central neural pathways to the auditory cortex. It provides essential ATP for auditory and vestibular system performance. Creatine kinase prevents cochlear damage by regulating the metabolism of energy in marginal layers of the striavascularis and preventing free radical production in stressful situations. It also plays an important role in vestibular compensation. Creatine kinase dysfunction leads to an increase in the threshold of auditory brainstem potentials and a reduction in vestibular performance. The use of creatine improves vestibular evoked myogenic potentials and neurologic symptoms.Conclusion: Creatine and creatine kinase protein is essential for normal hearing and balance function and sensitivity. Creatine kinase deficiency impairs the functioning of these two systems; however, creatine consumption may boost the sensitivity of the vestibular system and neurological performance. Effects of the creatine consumption on the auditory system have not yet been examined.

  2. Evaluation of embryonic alcoholism from auditory event-related potential in fetal rats

    Institute of Scientific and Technical Information of China (English)

    梁勇; 王正敏; 屈卫东

    2004-01-01

    @@ Auditory event-related potential (AERP) is a kind of electroencephalography that measures the responses of perception, memory and judgement to special acoustic stimulation in the auditory cortex. AERP can be recorded with not only active but also passive mode. The active and passive recording modes of AERP have been shown a possible application in animals.1,2 Alcohol is a substance that can markedly affect the conscious reaction of human. Recently, AERP has been applied to study the effects of alcohol on the auditory centers of the brain. Some reports have shown dose-dependent differences in latency, amplitude, responsibility and waveform of AERP between persons who have and have not take in alcohol.3,4 The epidemiological investigations show that the central nervous function of the offspring of alcohol users might be also affected.5,6 Because the clinic research is limited by certain factors, several animal models have been applied to examine the influences of alcohol on consciousness with AERP. In the present study, young rats were exposed to alcohol during fetal development and AERP as indicator was recorded to monitor the central auditory function, and its mechanisms and characteristics of effects of the fetal alcoholism on auditory center function in rats were analyzed and discussed.

  3. Neuronal connectivity and interactions between the auditory and limbic systems. Effects of noise and tinnitus.

    Science.gov (United States)

    Kraus, Kari Suzanne; Canlon, Barbara

    2012-06-01

    Acoustic experience such as sound, noise, or absence of sound induces structural or functional changes in the central auditory system but can also affect limbic regions such as the amygdala and hippocampus. The amygdala is particularly sensitive to sound with valence or meaning, such as vocalizations, crying or music. The amygdala plays a central role in auditory fear conditioning, regulation of the acoustic startle response and can modulate auditory cortex plasticity. A stressful acoustic stimulus, such as noise, causes amygdala-mediated release of stress hormones via the HPA-axis, which may have negative effects on health, as well as on the central nervous system. On the contrary, short-term exposure to stress hormones elicits positive effects such as hearing protection. The hippocampus can affect auditory processing by adding a temporal dimension, as well as being able to mediate novelty detection via theta wave phase-locking. Noise exposure affects hippocampal neurogenesis and LTP in a manner that affects structural plasticity, learning and memory. Tinnitus, typically induced by hearing malfunctions, is associated with emotional stress, depression and anatomical changes of the hippocampus. In turn, the limbic system may play a role in the generation as well as the suppression of tinnitus indicating that the limbic system may be essential for tinnitus treatment. A further understanding of auditory-limbic interactions will contribute to future treatment strategies of tinnitus and noise trauma. PMID:22440225

  4. Prenatal music stimulation facilitates the postnatal functional development of the auditory as well as visual system in chicks (Gallus domesticus)

    Indian Academy of Sciences (India)

    Saborni Roy; Tapas C Nag; Ashish Datt Upadhyay; Rashmi Mathur; Suman Jain

    2014-03-01

    Rhythmic sound or music is known to improve cognition in animals and humans. We wanted to evaluate the effects of prenatal repetitive music stimulation on the remodelling of the auditory cortex and visual Wulst in chicks. Fertilized eggs (0 day) of white leghorn chicken (Gallus domesticus) during incubation were exposed either to music or no sound from embryonic day 10 until hatching. Auditory and visual perceptual learning and synaptic plasticity, as evident by synaptophysin and PSD-95 expression, were done at posthatch days (PH) 1, 2 and 3. The number of responders was significantly higher in the music stimulated group as compared to controls at PH1 in both auditory and visual preference tests. The stimulated chicks took significantly lesser time to enter and spent more time in the maternal area in both preference tests. A significantly higher expression of synaptophysin and PSD-95 was observed in the stimulated group in comparison to control at PH1-3 both in the auditory cortex and visual Wulst. A significant inter-hemispheric and gender-based difference in expression was also found in all groups. These results suggest facilitation of postnatal perceptual behaviour and synaptic plasticity in both auditory and visual systems following prenatal stimulation with complex rhythmic music.

  5. 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.

  6. Synchronization of oscillatory neuronal responses between striate and extrastriate visual cortical areas of the cat.

    OpenAIRE

    Engel, A K; Kreiter, A K; König, P; Singer, W.

    1991-01-01

    Recent studies have shown that neurons in area 17 of cat visual cortex display oscillatory responses which can synchronize across spatially separate orientation columns. Here, we demonstrate that unit responses recorded from the posteromedial lateral suprasylvian area, a visual association area specialized for the analysis of motion, also exhibit an oscillatory temporal structure. Cross-correlation analysis of unit responses reveals that cells in area 17 and the posteromedial lateral suprasyl...

  7. Auditory cortical deactivation during speech production and following speech perception: an EEG investigation of the temporal dynamics of the auditory alpha rhythm.

    Science.gov (United States)

    Jenson, David; Harkrider, Ashley W; Thornton, David; Bowers, Andrew L; Saltuklaroglu, Tim

    2015-01-01

    Sensorimotor integration (SMI) across the dorsal stream enables online monitoring of speech. Jenson et al. (2014) used independent component analysis (ICA) and event related spectral perturbation (ERSP) analysis of electroencephalography (EEG) data to describe anterior sensorimotor (e.g., premotor cortex, PMC) activity during speech perception and production. The purpose of the current study was to identify and temporally map neural activity from posterior (i.e., auditory) regions of the dorsal stream in the same tasks. Perception tasks required "active" discrimination of syllable pairs (/ba/ and /da/) in quiet and noisy conditions. Production conditions required overt production of syllable pairs and nouns. ICA performed on concatenated raw 68 channel EEG data from all tasks identified bilateral "auditory" alpha (α) components in 15 of 29 participants localized to pSTG (left) and pMTG (right). ERSP analyses were performed to reveal fluctuations in the spectral power of the α rhythm clusters across time. Production conditions were characterized by significant α event related synchronization (ERS; pFDR < 0.05) concurrent with EMG activity from speech production, consistent with speech-induced auditory inhibition. Discrimination conditions were also characterized by α ERS following stimulus offset. Auditory α ERS in all conditions temporally aligned with PMC activity reported in Jenson et al. (2014). These findings are indicative of speech-induced suppression of auditory regions, possibly via efference copy. The presence of the same pattern following stimulus offset in discrimination conditions suggests that sensorimotor contributions following speech perception reflect covert replay, and that covert replay provides one source of the motor activity previously observed in some speech perception tasks. To our knowledge, this is the first time that inhibition of auditory regions by speech has been observed in real-time with the ICA/ERSP technique. PMID:26500519

  8. On Schr\\"odinger's cat

    CERN Document Server

    de Silva, Nalin

    2010-01-01

    Schr\\"odinger's cat appears to have been harassed in a chamber during the past eighty years or so by interpreting the role of the observer as a person, who sets an experiment and then observes results, may be after some time. The realist position tells us that the physical processes would take place independent of the observer with well defined properties, whereas the positivist position wants us to believe that nothing can be said of a system when it is not being observed. In this paper we question both these positions and also the assumption that the atom and the cat are entangled and further whether the atom could be considered to be in a state of decay and not decay. We let the cat either out of the bag (chamber) or rest in peace with or without the atom or the observer.

  9. Cat Ownership Perception and Caretaking Explored in an Internet Survey of People Associated with Cats.

    Science.gov (United States)

    Zito, Sarah; Vankan, Dianne; Bennett, Pauleen; Paterson, Mandy; Phillips, Clive J C

    2015-01-01

    People who feed cats that they do not perceive they own (sometimes called semi-owners) are thought to make a considerable contribution to unwanted cat numbers because the cats they support are generally not sterilized. Understanding people's perception of cat ownership and the psychology underlying cat semi-ownership could inform approaches to mitigate the negative effects of cat semi-ownership. The primary aims of this study were to investigate cat ownership perception and to examine its association with human-cat interactions and caretaking behaviours. A secondary aim was to evaluate a definition of cat semi-ownership (including an association time of ≥1 month and frequent feeding), revised from a previous definition proposed in the literature to distinguish cat semi-ownership from casual interactions with unowned cats. Cat owners and semi-owners displayed similar types of interactions and caretaking behaviours. Nevertheless, caretaking behaviours were more commonly displayed towards owned cats than semi-owned cats, and semi-owned cats were more likely to have produced kittens (pcats in semi-ownership relationships compared to casual interaction relationships. Determinants of cat ownership perception were identified (pcat friendliness and health, and feelings about unowned cats, including the acceptability of feeding unowned cats. Encouraging semi-owners to have the cats they care for sterilized may assist in reducing the number of unwanted kittens and could be a valuable alternative to trying to prevent semi-ownership entirely. Highly accessible semi-owner "gatekeepers" could help to deliver education messages and facilitate the provision of cat sterilization services to semi-owners. This research enabled semi-ownership to be distinguished from casual interaction relationships and can assist welfare and government agencies to identify cat semi-owners in order to develop strategies to address this source of unwanted cats. PMID:26218243

  10. Cognition without Cortex.

    Science.gov (United States)

    Güntürkün, Onur; Bugnyar, Thomas

    2016-04-01

    Assumptions on the neural basis of cognition usually focus on cortical mechanisms. Birds have no cortex, but recent studies in parrots and corvids show that their cognitive skills are on par with primates. These cognitive findings are accompanied by neurobiological discoveries that reveal avian and mammalian forebrains are homologous, and show similarities in connectivity and function down to the cellular level. But because birds have a large pallium, but no cortex, a specific cortical architecture cannot be a requirement for advanced cognitive skills. During the long parallel evolution of mammals and birds, several neural mechanisms for cognition and complex behaviors may have converged despite an overall forebrain organization that is otherwise vastly different. PMID:26944218

  11. Spatial Stream Segregation by Cats.

    Science.gov (United States)

    Javier, Lauren K; McGuire, Elizabeth A; Middlebrooks, John C

    2016-06-01

    Listeners can perceive interleaved sequences of sounds from two or more sources as segregated streams. In humans, physical separation of sound sources is a major factor enabling such stream segregation. Here, we examine spatial stream segregation with a psychophysical measure in domestic cats. Cats depressed a pedal to initiate a target sequence of brief sound bursts in a particular rhythm and then released the pedal when the rhythm changed. The target bursts were interleaved with a competing sequence of bursts that could differ in source location but otherwise were identical to the target bursts. This task was possible only when the sources were heard as segregated streams. When the sound bursts had broad spectra, cats could detect the rhythm change when target and competing sources were separated by as little as 9.4°. Essentially equal levels of performance were observed when frequencies were restricted to a high, 4-to-25-kHz, band in which the principal spatial cues presumably were related to sound levels. When the stimulus band was restricted from 0.4 to 1.6 kHz, leaving interaural time differences as the principal spatial cue, performance was severely degraded. The frequency sensitivity of cats in this task contrasts with that of humans, who show better spatial stream segregation with low- than with high-frequency sounds. Possible explanations for the species difference includes the smaller interaural delays available to cats due to smaller sizes of their heads and the potentially greater sound-level cues available due to the cat's frontally directed pinnae and higher audible frequency range. PMID:26993807

  12. The Nucleon as a Holographic Cheshire Cat

    OpenAIRE

    Zahed, Ismail

    2014-01-01

    The Cheshire cat principle emerges naturally from the holographic approach of the nucleon in terms of a bulk instanton. The cat hides in the holographic direction. I briefly review the one-nucleon problem in the holographic limit.

  13. The nucleon as a holographic Cheshire cat

    International Nuclear Information System (INIS)

    The Cheshire cat principle emerges naturally from the holographic approach of the nucleon in terms of a bulk instanton. The cat hides in the holographic direction. I briefly review the one-nucleon problem in the holographic limit

  14. Cerebral cysticercosis in a cat : clinical communication

    Directory of Open Access Journals (Sweden)

    E.V. Schwan

    2002-07-01

    Full Text Available The metacestode of Taenia solium, Cysticercus cellulosae, was recovered from the brain of a cat showing central nervous clinical signs ante mortem. This is the first record of cerebral cysticercosis in a cat in South Africa.

  15. Osteolysis in cat-scratch fever

    International Nuclear Information System (INIS)

    The osteolysis associated with cat-scratch fever resembles more ominous conditions. The combination of osteolysis and unilateral regional adenopathy in a child or adolescent should suggest cat-scratch disease. Bone scans and CT verified the diagnosis

  16. Dipylidium (Dog and Cat Flea Tapeworm) FAQs

    Science.gov (United States)

    ... if my pet has a tapeworm infection? Although cats and dogs are rarely ill as a result of a ... and outdoor environments. Have your veterinarian treat your dogs and cats promptly if they have tapeworms. Clean up after ...

  17. ServCat Document Selection Guidelines

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The ServCat document selection guidelines were developed for selecting appropriate documents to upload into ServCat. When beginning to upload documents into...

  18. Sensory gating, inhibition control and gamma oscillations in the human somatosensory cortex

    OpenAIRE

    Chia-Hsiung Cheng; Chan, Pei-Ying S.; Niddam, David M.; Shang-Yueh Tsai; Shih-Chieh Hsu; Chia-Yih Liu

    2016-01-01

    Inhibiting the responses to irrelevant stimuli is an essential component of human cognitive function. Pre-attentive auditory sensory gating (SG), an attenuated neural activation to the second identical stimulus, has been found to be related to the performance of higher-hierarchical brain function. However, it remains unclear whether other cortical regions, such as somatosensory cortex, also possess similar characteristics, or if such a relationship is modality-specific. This study used magnet...

  19. Revisiting the Role of Infralimbic Cortex in Fear Extinction with Optogenetics

    OpenAIRE

    Do-Monte, Fabricio H; Manzano-Nieves, Gabriela; Quiñones-Laracuente, Kelvin; Ramos-Medina, Liorimar; Quirk, Gregory J.

    2015-01-01

    Previous rodent studies have implicated the infralimbic (IL) subregion of the medial prefrontal cortex in extinction of auditory fear conditioning. However, these studies used pharmacological inactivation or electrical stimulation techniques, which lack temporal precision and neuronal specificity. Here, we used an optogenetic approach to either activate (with channelrhodopsin) or silence (with halorhodopsin) glutamatergic IL neurons during conditioned tones delivered in one of two phases: ext...

  20. Functional gradients through the cortex, multisensory integration and scaling laws in brain dynamics

    OpenAIRE

    Gonzalo-Fonrodona, Isabel

    2008-01-01

    In the context of the increasing number of works on multisensory and cross-modal effects in cerebral processing, a review is made on the functional model of human brain proposed by Justo Gonzalo (1910-1986), in relation to what he called central syndrome (caused by unilateral lesion in the parieto-occipital cortex, equidistant from the visual, tactile and auditory projection areas). The syndrome is featured by a bilateral, symmetric and multisensory involvement, and by a functional depression...