SEARCH · PubMed Health

Results for “Auditory Perception”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources

PubMed2005

The hearing abilities of the prawn Palaemon serratus.

The mechanism of sound reception and the hearing abilities of the prawn (Palaemon serratus) have been studied using a combination of anatomical, electron microscopic and electrophysiological approaches, revealing that P. serratus is responsive to sounds ranging in frequency from 100 to 3000 Hz. It is the first time that the Auditory Brainstem Response (ABR) recording technique has been used on invertebrates, and the acquisition of hearing ability data from the present study adds valuable information to the inclusion of an entire sub-phylum of animals when assessing the potential impact of anthropogenic underwater sounds on marine organisms. Auditory evoked potentials were acquired from P. serratus, using two subcutaneous electrodes positioned in the carapace close to the supraesophageal ganglion and the statocyst (a small gravistatic organ located below the eyestalk on the peduncle of the bilateral antennules). The morphology of the statocyst receptors and the otic nerve pathways to the brain have also been studied, and reveal that P. serratus possesses an array of sensory hairs projecting from the floor of the statocyst into a mass of sand granules embedded in a gelatinous substance. It is the purpose of this work to show that the statocyst is responsive to sounds propagated through water from an air mounted transducer. The fundamental measure of the hearing ability of any organism possessing the appropriate receptor mechanism is its audiogram, which presents the lowest level of sound that the species can hear as a function of frequency. The statocyst of P. serratus is shown here to be sensitive to the motion of water particles displaced by low-frequency sounds ranging from 100 Hz up to 3000 Hz, with a hearing acuity similar to that of a generalist fish. Also, recorded neural waveforms were found to be similar in both amplitude and shape to those acquired from fish and higher vertebrates, when stimulated with low-frequency sound, and complete ablation of the electrophysiological response was achieved by removal of the statocyst.

Acoustic Stimulation↗

PubMed2004

Auditory temporal processes in normal-hearing individuals and in patients with auditory neuropathy.

OBJECTIVE: To study objectively auditory temporal processing in a group of normal hearing subjects and in a group of hearing-impaired individuals with auditory neuropathy (AN) using electrophysiological and psychoacoustic methods. METHODS: Scalp recorded evoked potentials were measured to brief silent intervals (gaps) varying between 2 and 50ms embedded in continuous noise. Latencies and amplitudes of N100 and P200 were measured and analyzed in two conditions: (1) active, when using a button in response to gaps; (2) passive, listening, but not responding. RESULTS: In normal subjects evoked potentials (N100/P200 components) were recorded in response to gaps as short as 5ms in both active and passive conditions. Gap evoked potentials in AN subjects appeared only with prolonged gap durations (10-50ms). There was a close association between gap detection thresholds measured psychoacoustically and electrophysiologically in both normals and in AN subjects. CONCLUSIONS: Auditory cortical potentials can provide objective measures of auditory temporal processes. SIGNIFICANCE: The combination of electrophysiological and psychoacoustic methods converged to provide useful objective measures for studying auditory cortical temporal processing in normals and hearing-impaired individuals. The procedure used may also provide objective measures of temporal processing for evaluating special populations such as children who may not be able to provide subjective responses.

Acoustic Stimulation↗

PubMed2006

Electrophysiological and behavioral evidence of auditory processing deficits in children with reading disorder.

OBJECTIVE: The aim of the research was to investigate auditory processing abilities in children with reading disorders using electrophysiological and behavioral tasks. METHODS: Differences in auditory processing between control, compensated (age appropriate reading skills with a history of reading disorder), and reading disordered groups were systematically investigated. RESULTS: The reading disorder group had significantly lower results than control and compensated reader groups for most tests in the reading and auditory processing test battery. All children with a reading disorder did not pass at least one behavioral test of auditory processing, and hence would be diagnosed clinically as having an auditory processing disorder (APD). The reading disorder group also had significantly smaller /ga/-evoked mismatch negativity (MMN) area than the control group. Compensated and control groups had similar results for the electrophysiological and behavioral auditory processing tests. Correlation analyses showed that reading fluency and accuracy and nonword scores (measured using Castle and Coltheart's word/nonword test) correlated significantly with most APD measures. CONCLUSIONS: The general profile of auditory processing deficits in children with reading disorder was a combination of deficits on frequency patterns (i.e. frequency pattern test) and absent or small /ga/-evoked MMN. Significant results from the correlation analyses support the co-morbidity of reading and auditory processing disorders. SIGNIFICANCE: Children with reading disorders are likely to have auditory processing disorders.

Acoustic Stimulation↗

PubMed2006

Acute and chronic effects of carbamazepine, phenytoin, valproate and vinpocetine on BAEP parameters and threshold in the guinea pig.

OBJECTIVE: To characterize the acute and chronic effects of the antiepileptic drugs (AEDs): carbamazepine (CBZ), phenytoin (PHT), valproic acid (VPA) and vinpocetine (VPC), at doses 20, 6, 30 and 2mg/kg, respectively, on the latencies and amplitudes of the waves of brainstem auditory evoked potentials (BAEPs) elicited by a supra-threshold stimulus alongside BAEP threshold. METHODS: BAEPs elicited by a stimulus of high (100dB nHL) intensity and BAEP thresholds were obtained at 4 and 8kHz: before, after the start of treatment, and following 28 days of a daily injection of the AEDs. RESULTS: After the start of treatment BAEPs were unchanged. After the long term treatment, CBZ and PHT increased P3 and P4 wave peak latencies and reduced P4 amplitude. Chronic VPA did not modify BAEP waves, and chronic VPC reduced P3 and P4 latencies. P1 and P2 were unchanged. BAEP thresholds at 4 and 8kHz were increased by CBZ, PHT and VPA, and decreased by VPC. CONCLUSIONS: The chronic administration of several AEDs modifies BAEP waves of retro-cochlear origin. SIGNIFICANCE: Alterations in the generators of the later waves of BAEPs underlie, in most cases, the changes in hearing sensitivity produced by the long term treatment with AEDs at therapeutic relevant doses.

Acoustic Stimulation↗

PubMed2004

Effects of the neonatal intensive care unit on auditory attention and distraction.

A theory is proposed that attention to acoustic signals is important for normal development and varies with background masking sounds. Specifically, the theory states that distractibility increases with decreasing predictability of the acoustic environment and with decreasing age. Literature from premature neonates, normal infants, preadolescent children, children with attention deficit disorders, and adults is reviewed. One conclusion is that an environment perceived by adults as predictable may be distracting for preterm infants. One recommendation for future research is to include measures of background acoustic predictability as independent variables or covariates in developmental studies.

Attention↗

PubMed2005

Coordination of bowing and fingering in violin playing.

Playing string instruments implies motor skills including asymmetrical interlimb coordination. How special is musical skill as compared to other bimanually coordinated, non-musical skillful performances? We succeeded for the first time to measure quantitatively bimanual coordination in violinists playing repeatedly a simple tone sequence. A motion analysis system was used to record finger and bow trajectories for assessing the temporal structure of finger-press, finger-lift (left hand), and bow stroke reversals (right arm). The main results were: (1) fingering consisted of serial and parallel (anticipatory) mechanisms; (2) synchronization between finger and bow actions varied from -12 ms to 60 ms, but these 'errors' were not perceived. The results suggest that (1) bow-finger synchronization varied by about 50 ms from perfect simultaneity, but without impairing auditory perception; (2) the temporal structure depends on a number of combinatorial mechanisms of bowing and fingering. These basic mechanisms were observed in all players, including all amateurs. The successful biomechanical measures of fingering and bowing open a vast practical field of assessing motor skills. Thus, objective assessment of larger groups of string players with varying musical proficiency, or of professional string players developing movement disorders, may be helpful in music education.

Adult↗

PubMed2005

Spatial representation of pitch height: the SMARC effect.

Through the preferential pairing of response positions to pitch, here we show that the internal representation of pitch height is spatial in nature and affects performance, especially in musically trained participants, when response alternatives are either vertically or horizontally aligned. The finding that our cognitive system maps pitch height onto an internal representation of space, which in turn affects motor performance even when this perceptual attribute is irrelevant to the task, extends previous studies on auditory perception and suggests an interesting analogy between music perception and mathematical cognition. Both the basic elements of mathematical cognition (i.e. numbers) and the basic elements of musical cognition (i.e. pitches), appear to be mapped onto a mental spatial representation in a way that affects motor performance.

Adult↗

PubMed2004

Pulse rate discrimination with deeply inserted electrode arrays.

Pulse rate difference limen (PRDL) and amplitude modulation difference limen (AMDL) were assessed as a function of base rate and cochlear electrode location in seven (three for AMDL) subjects implanted with the MED-EL COMBI 40+ implant. The MED-EL COMBI 40+ electrode array allows deep insertion of the electrode up to the apex of the cochlea to minimize the rate/place mismatch for pulse rates below 500 pps. A three interval, two alternative forced-choice procedure with feedback was used to measure the difference limen. The base rate was in the range between 200 and 800 pps. The carrier rate for the AMDL measurement was 5081 pps. The PRDL increased with increasing base pulse rate. At 200 pps the average PRDL measured at the apical electrode amounted to 48.7 pps, at 400 pps the average PRDL reached 206.6 pps. No significant difference between PRDL obtained from apical or basal electrodes could be observed. AMDL was higher than PRDL at all tested base rates. The ability to discriminate rate changes is limited to base rates up to about 283 pps. The results indicate that rate changes smaller than a major third do not elicit distinguishable auditory perceptions in electrical hearing. The absence of a difference between apical and basal electrode locations indicates that a reduction of the rate/place mismatch does not improve discrimination performance.

Adult↗

PubMed2005

Development of the human fetal cochlear nerve: a morphometric study.

Ontogenesis of the human peripheral auditory pathway is relatively less explored. While the distal part of the auditory perception apparatus (i.e. the cochlea) received attention, studies on the neural element carrying information to the brainstem (i.e. the cochlear nerve) are scarce. In the present study, axonal differentiation, maturation and myelination of the distal end of the human cochlear nerve (CN) were assessed using light and electron microscopy. Seven human fetuses of 12, 15, 18, 20, 22, 28 and 38 weeks' gestation (WG) were analyzed. Light microscopy revealed nerve fascicles as early as 12 WG, initially arranged loosely but later compacted by 18 WG. Myelinated fibers were clearly detected at 28 WG. Ultrastructurally, at 12 WG developing Schwann cells were present between the thin unmyelinated axons. At 15 WG, the fascicular arrangement was distinct with blood vessels in the perineurium. The maximum number of axons was found at 20 WG, which subsequently reduced to reach the adult level at 22 WG. The myelinated axons in the CN were first observed on the left side at 20 WG, following which the number and proportion of myelinated axons increased until term, incorporating both small and large axons. The right CN lagged behind in maturation. Axon size also increased with age. Thus, the maturation of the human CN commences during the mid-gestation period and produces exuberant axons that are eventually pruned at a time when axons start to myelinate. During this developmental period the human CN maintains maturational asymmetry, the functional consequences of which remain to be elucidated.

Axons↗

PubMed2005

Compression estimates using behavioral and otoacoustic emission measures.

Cochlear compression in normal-hearing listeners was estimated at octave frequencies from 250 to 4000 Hz using a forward-masking paradigm. Temporal masking curves (TMCs) for a 10-dB SL signal were obtained with two maskers -- one equal in frequency to the signal and another an octave below the signal. The ratio of the slope of the off-frequency function to that of the mid-level portion of the on-frequency function was computed as an estimate of the amount of compression at each frequency. Compression was less frequency selective at low frequencies, so an average of the off-frequency slopes at high frequencies (1000, 2000, and 4000 Hz) was used in computing the ratio for each signal frequency. Results indicated strong compression (approximately 0.15-0.30) at all frequencies using the averaged off-frequency slopes, indicating little difference in compression across frequencies. Distortion product otoacoustic emission (DPOAE) input-output (I-O) functions were obtained for each subject at 1000, 2000, and 4000 Hz. The slopes of the DPOAE I-O functions and the psychophysical growth rates were similar to one another, reinforcing the assumption that the forward-masking procedure is providing an estimate of cochlear compression, at least at frequencies from 1000 to 4000 Hz.

Acoustic Impedance Tests↗

PubMed2005

Auditory nerve representation of naturally-produced vowels with variable acoustics.

This investigation compared the encoding of naturally-produced, whispered and normally-voiced vowels by auditory nerve fibers. Speech syllables containing the vowels /open o/ and /ae/ were produced by two female speakers and presented at three intensities to ketamine-anesthetized chinchillas. Six different representations of the spectral components in the vowels in the responses of the auditory nerve fibers were evaluated. For both normal and whispered vowels over a 30 dB range, the formant peaks in the vowel were best displayed using rate-place representations. The spectral detail in the vowel was revealed by average localized synchronized rates (ALSR) and autocorrelations of individual peristimulus time histograms. The average localized interval rates (ALIR), autocorrelations of ensemble responses, and autocorrelations of individual spike trains demonstrated poor representations of vowel spectra, although the frequency components of normally-voiced vowels had better representations than those of whispered vowels. These analyses suggest that rate-based and synchronization-based measures yields two very different pieces of information, but only a normalized rate-based measure consistently identified the formants of both the whispered and normally-voiced vowels.

Acoustic Stimulation↗

PubMed2006

A quantitative analysis of psychometric functions for different auditory tasks in gerbils.

The psychometric function relates the probability of a correct response to the variation of a physical stimulus parameter. In many perceptual tasks one point on this function is defined by a more or less arbitrary threshold criterion and threshold is used to study the effects of various treatments or age. Besides threshold, the shape of the psychometric function provides additional information. The variability of internal (neural) noise and the sensorineural transduction function will affect the shape of the psychometric function and may, therefore, reveal important features in the processing of stimulus characteristics. Here we analyze the effect of age on psychometric functions from gerbils: (A) for the detection of a tone or noise pulse in silence which is generally regarded as a measure of cochlear function and (B) for a gap detection task, investigating aspects of temporal processing that involve the ascending auditory pathway. Our data show that the slope of the psychometric function for the detection of tone and noise pulses in silence is independent of age and threshold. In contrast, the steepness of the psychometric function is decreased in gerbils with impaired temporal resolution. We discuss these observations in the context of physiological data from young and old animals.

Acoustic Stimulation↗

PubMed2006

Auditory abilities of speakers who persisted, or recovered, from stuttering.

OBJECTIVE: The purpose of this study was to see whether participants who persist in their stutter have poorer sensitivity in a backward masking task compared to those participants who recover from their stutter. DESIGN: The auditory sensitivity of 30 children who stutter was tested on absolute threshold, simultaneous masking, backward masking with a broadband and with a notched noise masker. The participants had been seen and diagnosed as stuttering at least 1 year before their 12th birthday. The participants were assessed again at age 12 plus to establish whether their stutter had persisted or recovered. Persistence or recovery was based on participant's, parent's and researcher's assessment and Riley's [Riley, G. D. (1994). Stuttering severity instrument for children and adults (3rd ed.). Austin, TX: Pro-Ed.] Stuttering Severity Instrument-3. Based on this assessment, 12 speakers had persisted and 18 had recovered from stuttering. RESULTS: Thresholds differed significantly between persistent and recovered groups for the broadband backward-masked stimulus (thresholds being higher for the persistent group). CONCLUSIONS: Backward masking performance at teenage is one factor that distinguishes speakers who persist in their stutter from those who recover. Education objectives: Readers of this article should: (1) explain why auditory factors have been implicated in stuttering; (2) summarise the work that has examined whether peripheral, and/or central, hearing are problems in stuttering; (3) explain how the hearing ability of persistent and recovered stutterers may differ; (4) discuss how hearing disorders have been implicated in other language disorders.

Adolescent↗

PubMed2004

Evaluation of hearing and auditory nerve function by combining ABR, DPOAE and eABR tests into a single recording session.

In this article, we describe an efficient method for testing both auditory receptor and auditory nerve function in a single recording session. Auditory receptor function is tested in response to pure tone, tone burst and click acoustic stimuli (i.e. distortion products of otoacoustic emissions, DPOAE; and auditory-evoked brainstem responses, ABR). The function of the auditory neurons and nerve is measured in response to direct electric current stimulation (i.e. electrically evoked auditory brainstem responses, eABR). All measurements were obtained from anesthetized laboratory rats during single recording sessions using hardware and software stimulation and analysis programs developed by Intelligent Hearing Systems, Miami, FL.

Acoustic Stimulation↗

PubMed2006

Intensity dependence of auditory-evoked cortical potentials in fibromyalgia patients: a test of the generalized hypervigilance hypothesis.

UNLABELLED: On the basis of recent evidence concerning the amplification of incoming stimulation in fibromyalgia (FM) patients, it has been proposed that a generalized hypervigilance of painful and nonpainful sensations may be at the root of this disorder. So far, research into this issue has been inconclusive, possibly owing to the lack of agreement as to the operational definition of "generalized hypervigilance" and to the lack of robust objective measures characterizing the sensory style of FM patients. In this study, we recorded auditory-evoked potentials (AEPs) elicited by tones of increasing intensity (60, 70, 80, 90, and 105 dB) in 27 female FM patients and 25 healthy controls. Fibromyalgia patients presented shorter N1 and P2 latencies and a stronger intensity dependence of their AEPs. Both results suggest that FM patients may be hypervigilant to sensory stimuli, especially when very loud tones are used. The most noteworthy difference between patients and control subjects is at the highest stimulus intensity, for which far more patients maintained increased N1-P2 amplitudes in relation to the 90-dB tones. The larger AEP amplitudes to the 105-dB tones suggest that defects in an inhibitory system protecting against overstimulation may be a crucial factor in the pathophysiology of FM. Because a stronger loudness dependence of AEPs has been related to weak serotonergic transmission, it is hypothesized that for many FM patients deficient inhibition of the response to noxious and intense auditory stimuli may be due to a serotonergic deficit. PERSPECTIVE: The study of auditory-evoked potentials in response to tones of increasing intensity in FM patients may help to clarify the pathophysiology of this disorder, especially regarding the role of inhibition deficits involving serotonergic dysfunction, and may be a useful tool to guide the pharmacologic treatment of FM patients.

Acoustic Stimulation↗

PubMed2006

Perceptual identification and acoustic measures of the resonant voice based on "Lessac's Y-Buzz"--a preliminary study with actors.

This study aimed to verify whether the resonant voice based on Lessac's Y-Buzz can be perceived by listeners as resonant and different from habitual voice and to compare them to determine whether this sound exploration improves the vocal production. Nine newly graduated actors, six men and three women without voice complaints, were the subjects. They received a session of Lessac's Y-Buzz training from the primary investigator. Before training, they were asked to sustain the vowel /i/ at comfortable frequency and habitual loudness. After training, they were requested to sustain the Y-Buzz they had learned at a comfortable frequency and habitual loudness. Three speech-language pathologists (SLP) trained in voice developed an auditory-perceptive analysis. The pre- and posttraining voice samples were randomly spliced together, edited, and presented in pairs to perceptual judges who were asked to identify the most resonant of the pair. The voice samples were also acoustically compared through the Hoarseness Diagram and acoustic measures using the VoxMetria Software (CTS, version 2.0s, Brazil). The Y-Buzz trials were identified as resonant voice in 74% of the comparisons. The acoustic measures showed a statistically significant decrease of irregularity (P = 0.002) and shimmer (P = 0.38). The Hoarseness Diagram demonstrated how the resonant voice moved toward the normality for irregularity and noise components. The results showed that the resonant voice based on the Y-Buzz can be identified as resonant and different from normal voicing in the same subject, and it apparently implies a better vocal production demonstrating a significant decrease of shimmer and irregularity through the Hoarseness Diagram evaluation.

Adolescent↗

PubMed2004

Auditory sensory gating deficit in abstinent chronic alcoholics.

P50 event-related potential was studied in abstinent chronic alcoholics to determine whether they had normal sensory gating. Repeated tones were presented to 17 recently detoxified chronic alcoholic patients and 17 healthy subjects while EEG was recorded. Low-resolution tomography (LORETA) was performed to obtain cerebral sources of P50. Abstinent chronic alcoholics showed reduced P50 sensory gating. Present results suggest an inhibitory deficit in early pre-attentive auditory sensory processing in chronic alcoholism.

Acoustic Stimulation↗

PubMed2005

The effects of antioxidants in the senescent auditory cortex.

We investigated whether a 2-month dietary supplementation of antioxidants, in the form of blueberry phytochemicals, could reverse or retard the age-related decline in temporal processing speed observed in the aged rat. To this end, extracellular single unit responses to frequency modulated (FM) sweeps were recorded in the primary auditory cortex (AI) of aged rats that had been placed on either a blueberry-supplemented or control diet 2 months prior to the physiological recordings. Results showed that most cells recorded from the blueberry-fed rats responded most vigorously to fast FM sweeps, similar to that observed in young rats. In contrast, the majority of cells recorded from the control rats showed a preference for slow FM sweep rates. These results suggest that age-related changes in temporal processing speed in A1 may be reversed by dietary supplementation of blueberry phytochemicals.

Action Potentials↗