Auditory Cortical Areas

While these effects must be interpreted cautiously due to the small sample sizes, they indicate that functional responses in auditory cortical areas are altered by visual deprivation and that intramodal auditory plasticity may underlie previously reported auditory advantages observed in the blind..  

However, these effects were modulated by stimulus frequency, as attempting to ignore auditory information resulted in the obligatory recruitment of auditory cortical areas during infrequent (0.5 Hz) stimulation. Robust ARMs were observed in both visual and auditory cortical areas at higher frequencies (2 Hz), indicating that participants effectively allocated attention to more rapidly presented targets.  

The auditory cortical areas examined included the anterior auditory field (AAF), primary auditory cortex (AI), dorsal zone (DZ), secondary auditory cortex (AII), field of the rostral suprasylvian sulcus (FRS), field anterior ectosylvian sulcus (FAES) and the posterior auditory field (PAF).  

A statistically significant stimulus type by repetition interaction was found in various bilateral auditory cortical areas, demonstrating either HR suppression and enhancement for repeated spoken words and pseudowords, respectively, or word-specific repetition suppression without any significant effects for pseudowords.  

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.  

Primary and secondary auditory cortical areas were inactivated by cooling.  

The present data add to growing evidence of multisensory convergence in cortical areas previously considered to be 'unimodal', and also indicate that auditory cortical areas differ in this respect..  

Structural equation modeling revealed increased influence of bilateral auditory cortical areas on right frontal areas during shifted speech, indicating that projections from auditory error cells in posterior superior temporal cortex to motor correction cells in right frontal cortex mediate auditory feedback control of speech..  

Low-level auditory cortical areas, however, showed comparatively little amplification of changes that crossed category boundaries.  

Substantial deficits were found only in animals with lesions that included secondary as well as primary auditory cortical areas.  

Another group of ferrets received larger lesions, encompassing both primary and nonprimary auditory cortical areas, and showed a greater deficit with performance being impaired for long- and short-duration (500- and 40-ms, respectively) stimuli.  

These data indicate that multisensory convergence and integration are features common to all auditory cortical areas but are especially prevalent in higher areas..  

This could possibly imply a stronger early amygdala activation in these participants, which then mediates the development of conditioning-related reorganization in auditory cortical areas..  

No significant retrograde labeling was found in auditory cortical areas.  

This network included the primary motor and somatosensory cortices, auditory cortical areas, supplementary motor area (SMA), the precentral gyrus of the insula, and portions of the thalamus, basal ganglia, and cerebellum.  

The main finding was increased activation with increasing level in cochlear nucleus, superior olive, inferior colliculus, medial geniculate body and auditory cortical areas.  

In accordance to previous studies, we found activation clusters bilaterally in visual, somatosensory, vestibular and auditory cortical areas for the contrast eyes-closed vs.  

This observation is consistent with the proposal that musical hallucinations represent abnormal spontaneous activity in auditory cortical areas beyond the primary auditory cortex.  

After the treatment period, spontaneous and stimulus-evoked activity from the somatosensory, visual and auditory cortical areas was recorded.  

The aim of the present study is to find out, by means of whole-scalp magnetoencephalography (MEG), whether vibrotactile stimulation alone would activate human auditory cortical areas.  

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.  

There was no significant change observed in the coherence between Broca's and Wernicke's areas, but a significant increase was observed in coherence between the left and right superior temporal cortices during AHs compared with non-AHs, suggesting increased bilateral coherence between auditory cortical areas.  

Most people intuitively understand what it means to "hear a tune in your head." Converging evidence now indicates that auditory cortical areas can be recruited even in the absence of sound and that this corresponds to the phenomenological experience of imagining music.  

This finding is similar to those of enhanced processing of tones in right auditory cortical areas and of rapid stimuli on the left, given strong crossed connections from ear to brain.  

The results of this study therefore implicate right anterior auditory cortical areas in making pitch judgements relative to tones that were heard previously.  

The results also provide a straightforward neural account of learned aspects of perceptual distortion near sound categories: Sounds from the center of a category are more difficult to discriminate from each other than sounds near category boundaries because they are represented by fewer cells in the auditory cortical areas..  

The goal of this study was to determine the temporal response properties of different auditory cortical areas in humans. Phase-locked neural responses are recorded in four auditory cortical areas with intracerebral electrodes, and modulation transfer functions (MTFs) are computed from these responses.  

We recorded field potentials with epidural electrodes placed above the auditory cortical areas of cats.  

The purpose of the present study was to define auditory cortical areas in the dog on the basis of thalamocortical connectivity patterns.  

RALDH3-expressing cortical regions include most of the limbic lobe, with strongest expression in the anterior cingulate cortex, medial and lateral secondary visual cortices, auditory cortical areas, the secondary motor cortex and some association areas.  

We examine the functional characteristics of auditory cortical areas that are sensitive to spatial cues in the human brain, and determine whether they can be dissociated from parietal lobe mechanisms.  

Connections between the amygdala and auditory cortical areas TC, and the rostral, intermediate and caudal regions of area TA (TAr, TAi and TAc, respectively) in the macaque monkey (Macaca fuscata and Macaca nemestrina) were investigated following placements of cortical deposits of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP).  

We argue that the auditory cortices in the two hemispheres are relatively specialized, such that temporal resolution is better in left auditory cortical areas and spectral resolution is better in right auditory cortical areas.  

These results from the cat's auditory cortex, as well as more limited results from nonhuman primates, suggest a model in which the location of any particular sound source is represented in a distributed fashion within individual auditory cortical areas and among multiple cortical areas..  

The results suggests that (a) voice priming is mediated to a large extent by frequency characteristics of a particular voice, rather than by articulatory and other 'sequential' features that are eliminated in backward speech; (b) priming affects the processing of voices in auditory cortical areas within 200 ms after voice onset; and (c) explicit recognition of a voice in the priming phase is not a necessary condition for priming to occur..  

A multiplexed coding of complex sound is proposed whereby the contours set up widespread synchrony across those neurons in all auditory cortical areas that are activated by the texture of sound..  

Compared to monaurally stimulated normal-hearing subjects, the AEPs recorded from central electrode sites located over auditory cortical areas showed significant increases in inter-hemispheric waveform cross-correlation coefficients, and in inter-hemispheric AEP peak amplitude correlations.  

We studied the connections of eleven auditory cortical areas with the claustrum and the endopiriform nucleus in the cat, by means of cortical injections of either wheat germ agglutinin conjugated to horseradish peroxidase, or biotinylated dextran amines. These findings suggest that the intermediate region of the claustrum integrates inputs from all auditory cortical areas, and then sends the result of such processing back to every auditory cortical field.  

Nd-Frequency and Nd-Human Location waves had distinct scalp distributions, consistent with generation in different auditory cortical areas.  

The unilateral deafness in patients with GET was associated with expansion of auditory cortical areas responsive to tones delivered to the good ear.  

It is suggested that tinnitus is processed in primary, secondary and integrative auditory cortical areas.  

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.  

Our findings indicate that auditory cortical areas of human adults undergo functional reorganization following peripheral alteration of the sensory input entering the CNS.  

RESULTS: In the volunteers, audiovisual stimulation caused significant rCMRglc increases in visual and auditory cortical areas but significant decreases in frontal areas.  

Response properties of auditory cortical neurons measured in anesthetized preparations have provided important information on the physiological differences between neurons in different auditory cortical areas.  

Previous lesion and functional imaging studies in humans suggest a greater involvement of right rather than left auditory cortical areas in certain aspects of pitch processing. These findings support a specialization of function linked to right auditory cortical areas for the processing of pitch direction, and specifically suggest a dissociation between simple sensory discrimination and higher order perception..  

In the auditory cortex (AC), most prominently in the secondary area Te2, the number of Fos-like positive cells differed between "learning" and "control" rats, suggesting that the auditory cortical areas may be involved in the encoding of the behavioural significance of the acoustic stimuli..  

The first class of giant terminal was labeled after injections of biotinylated dextran amines (BDA) in seven auditory cortical areas.  

They also displayed enhanced N1 and P2 voltages, which may reflect the simultaneous activation of two different populations of neurons in the auditory cortical areas.  

The organization of these connections is discussed in relationship to the functional role of the auditory cortical areas..  

This study investigates the degree of similarity of three different auditory cortical areas with respect to the coding of periodic stimuli.  

The projection from 11 auditory cortical areas onto the subdivisions of the inferior colliculus was studied in adult cats by using two different anterograde tracers to label cortico-collicular (CC) axon terminals.  

Listening to musical tones resulted in similar patterns of increased cerebral blood flow in auditory cortical areas in both groups, as expected.  

Succinate dehydrogenase histochemistry provides a simple method for identifying auditory cortical areas and should be of use in future physiological studies.  

The results suggest that different auditory cortical areas have different temporal integration times, and that these functions vary as a function of tone frequency..  

The role of firing-rate and firing synchrony within and between three auditory cortical areas in coding complex sounds was investigated.  

Two further experiments suggest that these auditory cortical areas are not engaged when an individual is viewing nonlinguistic facial movements but appear to be activated by silent meaningless speechlike movements (pseudospeech).  

The EEG recorded in the KM rats hippocampus, caudate nucleus, central medial thalamic nucleus, somato-sensory, visual and auditory cortical areas, were analysed.  

This study investigated differentiation of Macaca fuscata auditory thalamus into chemically defined nuclei forming relays to auditory cortical areas. The thalamus was stained immunocytochemically for parvalbumin and 28 kDa calbindin in normals and in brains in which retrogradely transported tracers were injected into middle layers of auditory cortical areas or applied to the cortical surface.  

The connections of the auditory cortical areas with the posterior cingulate cortex in the macaque monkey were examined by retrograde and anterograde tracing methods using wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP).  

In the cat, the non-laminated portions of the MG are also known to project to the amygdala, as well as to the auditory cortical areas surrounding the primary auditory area.  

Auditory cortex with visual input did not make ectopic connections with visual cortex, but maintained its connections with other auditory cortical areas.  

Classical conditioning specifically modifies receptive fields in primary and secondary auditory cortical areas to favor the frequency of a tone signal over other frequencies, including tuning shifts toward, or to, this frequency.  

Morphological characteristics of the neurons of the auditory cortical areas of the rhesus monkey were investigated using Golgi and horseradish peroxidase methods.  

The origin and laminar arrangement of the homolateral and callosal projections to the anterior (AAF), primary (AI), posterior (PAF) and secondary (AII) auditory cortical areas were studied in the cat by means of electrophysiological recording and WGA-HRP tracing techniques.  

This specialization of posterior auditory cortical areas can be related to previous observations indicating that the anterior and posterior regions of the auditory cortex differ from each other by their response properties to sounds and their pattern of connectivity with the auditory thalamus and the claustrum..  

Therefore, the results of the present study show that the major extrinsic projections of the cat's visual and auditory cortical areas with subcortical structures are present by the eighth week of gestation, and that the origins and terminations of many of these projections are arranged topologically..  

A monosynaptic, bilateral connection, between morphophysiological auditory cortical areas and the nucleus of the oculomotor nerve was established by means of contemporary silver impregnation methods and radioautographical technique.  

AII injections also labeled cells in other auditory cortex subdivisions, including the posterior ectosylvian, ventroposterior, temporal, and dorsal auditory zone/suprasylvian fringe cortical areas, and in some non-auditory cortical areas.  

The major extrinsic projections to and from the visual and auditory cortical areas were examined in 4-day-old kittens using axonal transport of horseradish peroxidase (HRP) and/or tritiated proline. The results of the present study indicate that most or all of the major extrinsic connections of the kitten's visual and auditory cortical areas are present neonatally, and that both the cells of origin and the axonal targets are arranged topographically much like those of adult cats.  

In chronic experiments on cats dependence was studied of amplitudes and temporal parametres of evoked potentials (EPs) in the sensorimotor, parietal and auditory cortical areas on the frequency of tonal bursts 0.5-6.3 kHz.  

Impairment of the ability to localize a moving acoustic image was studied in animal (dogs) following experimental ablation of the auditory cortical areas, and in patients following unilateral electro-shock seizures and focal injuries of the temporal cortex.  

Each of fields A, AI, P, and VP is connected with the other three in the same hemisphere as well as with a number of other auditory cortical areas.  

The procedure maximizes the probability of locating and identifying auditory cortical areas during the chronic unit recording sessions and of identifying individual electrode tracks in subsequent histologic examination.  

The paper presents characteristics of evoked potentials appearing in response to afferent stimuli in the dolphin visual and auditory cortical areas.  

It was found that in intact animals auditory cortical areas are constantly involved in brain integrations whereas parietal ones show periodical participation (EPs in the parietal cortical area accompany some pairings of signal stimulus with reinforcement).  

The interrelationships of stimulation thresholds in the auditory cortical areas AI, AII, and Ep were studied in chronic experiments on cats.  

Evoked potentials (EP) in the somatosensory and auditory cortical areas were studied in four dogs against the background of a retarded defensive instrumental conditioned reflex to clicks.  

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