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J Jerger

Publications and source records attributed to J Jerger.

At least 55 records · Page 3Linked to original sources

Effect of handedness on the middle latency auditory evoked potential.

The effect of handedness on the middle latency response of the auditory evoked potential was investigated by testing 16 right-handed and 16 left-handed young adults with normal hearing. Each handedness group contained eight males and eight females. Peaks PO, N(a),P(a),Nb,and Pb showed a progressive, statistically significant latency increase in left-handed subjects when compared with right-handed subjects. The latency difference was 1.1 ms at peak P(a) and 3.6 ms at peak Pb. There was no significant latency difference between males and females. Topographic brain mapping showed that the distribution of positivity of wave Pb was similar to the distribution for wave P(a) in both right- and left-handed subjects.

Acoustic Stimulation↗

Some factors affecting assessment of hearing handicap in the elderly.

In 42 elderly hearing-impaired persons we compared the patient's self-assessment of hearing handicap with the assessment made by the patient's significant other. In general, patients tended to rate themselves as less handicapped than did their significant others. The difference was not affected by degree of loss but was affected by slope of loss and by the presence of central auditory processing deficit. Results support the value of the handicap assessment by the significant other in understanding the communication problems of the elderly patient.

Adult↗

Gender affects audiometric shape in presbyacusis.

A review of large-scale surveys of hearing over the past 50 years reveals a "gender-reversal" phenomenon in the average audiograms of the elderly. Above 1 kHz males show greater average loss than females, but below 1 kHz females show greater average loss than males. The effect increases with both age and degree of hearing loss. The difference is present whether or not the elderly persons complain of a hearing problem and remains after persons with a history of noise exposure are excluded from the analysis. A possible explanation, based on the greater likelihood of cardiovascular disease in the elderly female, is considered.

Aged↗

Case studies in binaural interference: converging evidence from behavioral and electrophysiologic measures.

We present four case reports of elderly hearing-impaired persons demonstrating a binaural interference effect. Performance measures were poorer when stimulation was binaural than when it was monaural. In the first case the effect is shown for aided speech recognition scores. In the second case it is shown in topographic brain maps of the middle-latency auditory evoked potential. In the third and fourth cases it is shown for both aided speech recognition and the middle-latency response. The effect may be analogous to the phenomenon of binocular rivalry in the visual domain.

Acoustic Stimulation↗

Age-related asymmetry on a cued-listening task.

We report results on a cued-listening task designed to simulate the listening problems commonly described by individuals with sensorineural hearing loss, especially those experienced by elderly persons. Against a background of multitalker babble, the subject detected targets embedded in continuous discourse. Noncoherent segments of this discourse were presented simultaneously from loudspeakers on the right and left sides. A signal light cued the side to be monitored during a listening trial. The overall difficulty of the task was manipulated by variation of the message to competition intensity ratio. A sequence of listening trials, half-cued to the right side, half cued to the left side, was executed at each of four message to competition intensity ratios. Nineteen young adults with normal hearing and 28 elderly persons with presbyacusic hearing loss were evaluated. All subjects, young and elderly, were able to complete the cued-listening task successfully. Results showed a small but significant right-side advantage in the young group and a substantial right-side advantage in the elderly group. The application of the testing technique to the evaluation of hearing aid performance is illustrated in two elderly persons.

Adult↗

Acoustic reflex abnormalities in cranial-cervical dystonia.

Previous anatomic and physiologic studies suggest brainstem dysfunction in cranial-cervical dystonia. To further explore this, we studied suprathreshold acoustic reflex waveforms in 15 such patients. A unique feature of this technique is its ability to reject movement artifacts before averaging the acoustic reflex waveforms. Thirteen patients (87%) showed some abnormality in reflex waveform morphology. There were both amplitude and latency abnormalities. These findings support the hypothesis that cranial-cervical dystonia reflects dysfunction of the brainstem.

Acoustic Stimulation↗

Phase coherence of the middle-latency response in the elderly.

We compared phase coherence of the auditory-evoked, middle-latency response (MLR) and the 40-Hz steady-state evoked potential (SSEP) in two groups of elderly listeners, matched for degree of audiometric hearing sensitivity loss. In group A, speech understanding was appropriate to the degree of audiometric sensitivity loss. In group B, speech understanding was disproportionately poor in relation to the degree of loss. In both modes of measurement (MLR and SSEP) phase coherence was significantly poorer in group B than in group A. In the case of MLR, maximum phase coherence was observed at the expected 40 Hz in group A, but at 30 Hz in group B. In the case of SSEP, maximum phase coherence was observed at 40 Hz in both groups but was poorer at almost all Fourier components in group B.

Acoustic Stimulation↗

Otoacoustic emissions, audiometric sensitivity loss, and speech understanding: a case study.

The clinical measurement of otoacoustic emissions can assist in differentiating between peripheral and central explanations for deficits in speech understanding. We present audiometric and distortion-product emission data in a case with sensorineural hearing loss and a deficit in speech understanding. The presence of evoked emissions argues against attributing the speech audiometric loss to cochlear defect.

Adult↗

Can age-related decline in speech understanding be explained by peripheral hearing loss?

Speech audiometric scores were compared across the age range from 50 to 90 years in 137 subjects selected in such a way that average audiometric thresholds were matched across four age groups. Thus any age-related changes in speech audiometric scores could not be attributed to age-related differences in peripheral hearing sensitivity. Four speech audiometric measures were studied; phonemically-balanced words (PB), Speech Perception in Noise (SPIN) test for both high- and low-predictability sentences, and the Synthetic Sentence Identification (SSI) test. There was an age trend for all four speech measures but only the change in SSI (30%) was statistically significant. The argument that the change in SSI can be explained by subtle changes in the auditory periphery, not reflected in audiometric thresholds, is weakened by the fact that the change in SSI was greater than the change in either of the two monosyllabic word tests (PB and SPIN-low). The argument that the change in SSI can be explained by concomitant cognitive decline is not supported by correlations among SSI performance and any of several neuropsychological measures of cognitive function in the same subjects. Finally, the lack of a significant interactive effect between hearing sensitivity level and cognitive status does not support a model in which a peripherally degraded speech signal interacts with a deficit in cognitive function to produce the decline in speech audiometric scores. We conclude that the observed age-related decline in SSI performance cannot be satisfactorily explained by peripheral hearing sensitivity loss.

Aged↗

Correlational analysis of speech audiometric scores, hearing loss, age, and cognitive abilities in the elderly.

A battery of speech audiometric measures and a battery of neuropsychological measures were administered to 200 elderly individuals with varying degrees of pure-tone sensitivity loss. Results were analyzed from the standpoint of the extent to which variation in speech audiometric scores could be predicted by knowledge of pure-tone hearing level, age, and cognitive status. For the four monotic test procedures (PB, SPIN-Low, SPIN-High, and SSI) degree of hearing loss bore the strongest relation to speech recognition score. Cognitive status accounted for little of the variance in any of these four speech audiometric scores. In the case of the single dichotic test procedure (DSI), both degree of hearing loss and speed of mental processing, as measured by the Digit Symbol subtest of the WAIS-R, accounted for significant variance. Finally, age accounted for significant unique variance only in the SSI score.

Aged↗

Effect of linguistic interference on sentence identification.

This study was designed to investigate the extent to which continuous speech competition, in sentence identification paradigm, produces linguistic interference over and above acoustic masking. We evaluated performance on the Synthetic Sentence Identification (SSI) test in 24 bilingual speakers of English and Spanish under four experimental conditions: (1) target and competition both in English, (2) target and competition both in Spanish, (3) target in English, competition in Spanish, and (4) target in Spanish, competition in English. After controlling for the effects of acoustic masking, results showed significantly better performance in conditions when target and competition were in different languages (interlingual interference) than when target and competition were in the same language (intralingual interference). The difference in performance is attributed to the effects of greater linguistic interference when target and competition were in the same language.

Acoustics↗

Central auditory processing disorder: a case study.

We carried out extensive audiologic, electrophysiologic, and neuropsychologic testing on a young woman who complained that she had difficulty hearing in her educational environment. Conventional audiometric results, including pure-tone, speech, and immittance audiometry, were all within normal limits. The subject performed normally on tests involving the processing of rapidly changing temporal information, interaural time and intensity difference detection, and both absolute and relative sound localization. Early, middle, late and task-related auditory evoked potentials were essentially normal, although some asymmetry was observed in the middle latency (MLR) and late (LVR) responses. There was, however, a consistent left-ear deficit on dichotic sentence identification, on threshold and suprathreshold speech measures in the left sound field when various types of competition were delivered in the right sound field, and on cued-target identification in the left sound field in the presence of multitalker babble. Results suggest a central auditory processing disorder characterized by an asymmetric problem in the processing of binaural, noncoherent signals in auditory space. When auditory space was structured such that the target was directed to the left ear, and the competition to the right ear, unwanted background was less successfully suppressed than when the physical arrangement was reversed.

Acoustic Impedance Tests↗

Analysis of gender differences in the auditory brainstem response.

This study examined the effects of hormones, head size, and oral temperatures on latencies and amplitudes of the auditory brainstem response in 10 young women, 10 young men, and 5 postmenopausal women. Significant gender differences between men's and women's auditory brainstem responses were confirmed. Men showed longer latencies and smaller amplitudes than women. Results showed that oral temperature has little effect on auditory brainstem response latencies and amplitudes. Head size affects waves III, V, and the amplitude of wave V, but is not entirely responsible for the gender latency difference. By examining young women with normal monthly hormonal cycles, significant changes in the absolute latencies of wave V were observed. These changes were correlated with hormonal changes as measured from venous blood samples. It was concluded that the etiology of the gender difference is a combination of hormonal and head-size differences.

Adult↗

The prevalence of central presbyacusis in a clinical population.

To evaluate the prevalence of central auditory disorder as a function of aging, we analyzed speech audiometric test results on 700 patients, 100 patients from each of seven half-decades beginning at age 50 years. In addition, we evaluated the extent to which prevalence estimates could be explained by the effect of hearing loss on measures of central auditory processing and the difference in prevalence of central presbyacusis between a clinical sample and a nonclinical sample. Results showed that the prevalence of central presbyacusis increased with age and that the highest prevalence was a striking 95 percent in the 80+ year age group. Results also showed that, even when degree of hearing loss and ability to perform the speech audiometric task were equated, the prevalence of central presbyacusis increased systematically with age. Finally, results showed that the prevalence was lower in the nonclinical sample than in the clinical sample at all ages, but that a substantial amount of central presbyacusis existed in the nonclinical subjects, especially in the oldest age groups.

Adult↗

The separability of central auditory and cognitive deficits: implications for the elderly.

After viral encephalitis a 40-year-old man showed both central auditory deficit and severe cognitive deficits. The asymmetric central auditory deficit was revealed by speech audiometry. The effect could be explained neither by peripheral sensitivity loss nor by cognitive status. Results highlight the separability of central auditory and cognitive deficits. Implications for the elderly are discussed.

Adult↗