Jane A. Baran

Gin (gaps-in-noise) Test Performance In Subjects With Confirmed Central Auditory Nervous System Involvement

Objective: The purpose of the present study was to investigate the value of a new gap detection procedure called Gaps-In-Noise (GIN) for assessment of temporal resolution in a clinical population. Design: The test consists of 0 to 3 silent intervals ranging from 2 to 20 msec embedded in 6-sec segments of white noise. The location, number, and duration of the gaps per noise segment vary throughout the test for a total of 60 gaps presented in each of four lists. The GIN procedure was administered to 50 normal-hearing listeners (group I) and 18 subjects with confirmed neurological involvement of the central auditory nervous system (group II). Results: Results showed mean approximated gap detection thresholds of 4.8 msec for the left ear and 4.9 msec for the right ear for group I. In comparison, results for group II demonstrated a statistically significant increase in gap detection thresholds, with approximated thresholds of 7.8 msec and 8.5 msec being noted for the left and right ears, respectively. Significant mean differences were also observed in the overall performance scores (i.e., the identification of the presence of the gaps within the noise segments) of the two groups of subjects. Finally, psychometric functions, although similar for short and long duration gaps, were highly different for gaps in the 4- to 10-msec range for the two groups. Conclusions: A variety of psychoacoustic procedures are available to assess temporal resolution; however, the clinical use of these procedures is minimal at best. Results of the present study show that the GIN test holds promise as a clinically useful tool in the assessment of temporal resolution in the clinical arena.

Duration Pattern Recognition in Normal Subjects and Patients with Cerebral and Cochlear Lesions

Three groups of subjects were tested on a duration pattern recognition task. The groups included normal subjects, subjects with cochlear hearing loss, and subjects with lesions involving but not limited to the auditory areas of the cerebrum. Results indicated no significant difference in pattern recognition between the normal subjects and subjects with cochlear hearing loss. However, the subjects with cerebral lesions performed significantly more poorly than either the normal subjects or those with cochlear hearing loss. In comparing pattern recognition performance for the ears ipsilateral and contralateral to the lesioned hemispheres no differences were noted. Rather, when a central lesion was present, both ears generally yielded abnormal scores.

Desempenho de adultos jovens normais em dois testes de resolução temporal

BACKGROUND temporal auditory processing is defined as the perception of sound or of sound alteration within a restricted time interval and is considered a fundamental ability for the auditory perception of verbal and non verbal sounds, for the perception of music, rhythm, periodicity and in the discrimination of pitch, duration and of phonemes. AIM to compare the performance of normal Brazilian adults in two temporal resolution tests: the Gaps-in-Noise Test (GIN) and the Random Gap Detection Test (RGDT), and to analyze potential differences of performance in these two tests. METHOD twenty-five college students with normal hearing (11 males and 14 females) and no history of educational, neurological and/or language problems, underwent the GIN and RGDT at 40dB SL. RESULTS statistically significant gender effects for both tests were found, with female participants showing poorer performance on both temporal processing tests. In addition, a comparative analysis of the results obtained in the GIN and RGDT revealed significant differences in the threshold measures derived for these two tests. In general, significantly better gap detection thresholds were observed for both male and female participants on the GIN test when compared to the results obtained for the RGDT. CONCLUSION male participants presented better performances on both RGDT and GIN, when compared to the females. There were no differences in performance between right and left ears on the GIN test. Participants of the present investigation, males and females, performed better on the GIN when compared to the RGDT. The GIN presented advantages over the RGDT, not only in terms of clinical validity and sensibility, but also in terms of application and scoring.

Hemispheric Specialization In Processing Intonation Contours

Abstract Hemispheric specialization in processing linguistic and non-linguistic intonation contours during sentence processing was examined in four experiments using subjects with unilateral left (LHD) or right hemisphere damage (RHD). When subjects were asked to identify intonation contours as questions or statements in semantically neutral sentences, the LHD group demonstrated a significantly poorer performance than the control group. No significant differences were found between the RHD and control groups. When subjects were asked to identify syntactically ambiguous sentences through the perception of intonation cues located at syntactic boundaries the same pattern of results emerged. In discriminating between the aforementioned segmentally identical sentences, no significant differences were found between groups. However, when the segmental information was degraded and subjects were asked to discriminate between isolated prosodic structures, the RHD group demonstrated a significantly poorer performanc...

Central auditory assessment: thirty years of challenge and change.

In this paper we discuss some of the major developments that have occurred in the field of central auditory assessment over the past 30 years. We discuss both the psychophysical and the electrophysiological procedures that have been used for either research and/or clinical purposes. Case illustrations from our own clinical experience are also provided. Finally, we conclude by suggesting directions for future research.

The Dichotic Rhyme Task - Results In Split-brain Patients

Monosyllabic rhyme words were dichotically presented to normal and complete split-brain subjects. In the normal adult population, only one of the words in the dichotic condition was identified. Hence, normal performance was about 50%, with a small but significant right-ear advantage. The split-brain patients yielded the expected marked left deficit, as seen on other dichotic speech tests, and demonstrated a right-ear enhancement, producing a large interear difference. This right-ear enhancement on the dichotic rhyme task (DRT) may suggest a release from central auditory competition in the left hemisphere. The dichotic rhyme tasks normative data results and sensitivity to lack of callosal transmission make it worthy of further clinical and basic research.

Central Auditory Function following Anterior Sectioning of the Corpus Callosum

This paper describes auditory findings for eight patients with anterior sections of the corpus callosum. Peripheral (pure tone and speech recognition) and five central auditory tests were administered to each of the eight patients prior to surgery and then again approximately 2 weeks after surgery. The central tests administered included a low-pass filtered speech test, the frequency patterns perception test, and three dichotic speech tests. Mean scores for the peripheral tests fell grossly within the normal range preoperatively and showed little change postoperatively. Similarly, scores on the central tests, though somewhat more variable, did not show any obvious differences upon pre-and postsurgical comparison. A comparison of these results with those reported previously for patients with complete commissurotomies (Musiek, Kibbe, and Baran. Semin Hear 1984;5:219–29) revealed that as a group, patients with anterior sections of the corpus callosum showed fewer postsurgery deficits than did the subjects with complete commissurotomies. The lack of an apparent auditory effect in the anterior group is believed to have an anatomical basis.

Gaps-in-noise (GIN©) test results in children with and without reading disabilities and phonological processing deficits.

Abstract Objective: To determine if the gaps-in-noise (GIN©) test could differentiate children with dyslexia and significant phonological awareness deficits from a group of children with normal reading skills. Design: A prospective study of GIN test performance in two groups of children. Participants were administered routine audiological tests, a phonological processing test, and an auditory temporal resolution test (GIN test). Statistical testing was completed to determine if significant differences existed between groups on GIN test results and phonological processing measures, and to examine potential relationships between these test measures. Routine clinical analysis procedures examined the performance of the two groups from a clinical perspective. Study sample: Participants included 61 children between the ages of 8 years, 1 month and 9 years, 11 months, separated into two groups: children with dyslexia and significant phonological deficits (Group I); normal-reading peers with age-appropriate phonological skills (Group II). Results: Children in Group I showed longer gap detection (GD) thresholds and lower gap identification scores than did the children in Group II. Results of statistical and clinical testing revealed significant differences between the groups. Conclusion: An auditory temporal processing deficit is a factor to be considered in children presenting with dyslexia and phonological processing disorders.

Central deafness: an audiological case study.

Cases of central deafness are rare but they can be most informative about the function and dysfunction of the central auditory nervous system. Previous information on the anatomy, physiology, and terminology related to central deafness is reviewed and a patient with central deafness is profiled. The patient suffered bilateral cerebrovascular accidents (CVAs) compromising Heschls gyrus and some adjacent neural tissue on both sides of the brain. At 18 months post CVAs, this patient could not understand speech presented solely through the auditory modality. Environmental sounds were perceived, but rarely recognized. Pure-tone testing revealed a severe-to-profound hearing loss bilaterally, but otoacoustic emissions, acoustic reflexes, and the auditory brainstem response were essentially within normal ranges for both ears. Middle late and late auditory potentials were compromised, yielding complex modifications of the waveforms. These findings and the compromised vascular anatomy in this case are detailed in this article.

New developments in the assessment and management of auditory processing disorders

This paper discusses three new developments in the assessment and management of auditory professing disorders (APD) that hold great potential for clinical application in the future. These developments include: 1) the introduction of a new test of temporal resolution (a gap detection test), which promises to fill a void in the current APD assessment arena; 2) the development of a novel intervention approach designed to facilitate resolution of ear differences noted during dichotic speech testing; and 3) the application of electrophysiological test measures to document the efficacy of auditory training programs as rehabilitative strategies. Each of these developments will be described and the available data to support its use in the assessment and/or management of individuals with APD will be discussed.