Techniques for Use on.-Google Books Result Hearing in vertebrates: A psychophysics databook. Get this from a library! Hearing in vertebrates: a psychophysics databook. Richard R Fay Hearing in vertebrates: a psychophysics databook / Richard R. Fay The chapters of this volume review what is understood about the similarities and differences among mammals in their sense of hearing, defined behaviorally, .

The present investigation examined the effect of reverberation and noise on the perception of nonsense syllables by four groups of subjects: younger (≤35 years of age) and older (>60 years of age) listeners with mild-to-moderate sensorineural hearing loss; younger, normal-hearing individuals; and older adults with minimal peripheral hearing loss. Copies of the Nonsense Syllable Test (Resnick, Dubno, Huffnung, & Levitt, 1975) were re-recorded under four levels of reverberation (0.0, 0.6, 0.9, 1.3 s) in quiet and in cafeteria noise at + 10 dB S:N. Results suggest that both age and amount of pure-tone hearing loss contribute to senescent changes in the ability to understand noisy, reverberant speech: pure-tone threshold and age were correlated negatively with performance in reverberation plus noise, although age and pure-tone hearing loss were not correlated with each other. Further, many older adults with minimal amounts of peripheral hearing loss demonstrated difficulty understanding distorted consonants.

The ability of the two hemispheres of the brain to communicate with one another via the corpus callosum is important for a wide variety of sensory, motor, and cognitive functions, many of them communication related. Anatomical evidence suggests that aging results in structural changes in the corpus callosum and that the course over time of age-related changes in corpus callosum structure may depend on the gender of the individual. Further, it has been hypothesized that age- and gender-related changes in corpus callosum structure may result in concomitant decreased performance on tasks that are reliant on interhemispheric integrity. The purpose of this study was to investigate the effects of age and gender on auditory behavioral and visuomotor temporal indices of interhemispheric function across the life span of the normal adult. Results from 120 consistently right-handed adults from age 20 to 75 years revealed that interhemispheric integrity, as measured by dichotic listening, auditory temporal patterning, and visuomotor interhemispheric transfer time tasks, decreases relatively early in the adult life span (i.e., between the ages of 40 and 55 years) and shows no further decrease thereafter. In addition, the course over time of interhemispheric decline is different for men compared to women for some tasks. These findings suggest that decreased interhemispheric function may be a possible factor contributing to auditory and communication difficulties experienced by aging adults. In addition, results of this study hold implications for the clinical assessment of interhemispheric function in aging adults and for future research into the functional ramifications of decreased multimodality interhemispheric transfer.

The potential risk to hearing that mass-storage personal listening devices ͑PLDs͒ pose remains unclear. Previous research in this area has either focused on maximum outputs of these devices or on ear-canal measurements of listening levels that could not be compared to standards of occupational noise exposure. The purpose of this study was to compare two standard measurement protocols ͓ISO 11904-1 ͑2002͒, Switzerland; ISO 11904-2 ͑2004͒, Switzerland͔ for the measurement of preferred listening levels of PLD. Noise measurements, behavioral thresholds, and oral interviews were obtained from 30 ͑18-30 years͒ PLD users. Preferred listening levels for self-selected music were determined in quiet and background noise using a probe microphone, as well as in the DB-100 ear simulator mounted in KEMAR. The ear-canal measurements were compensated for diffuse-field. Only one of the subjects was found to be listening at hazardous levels once their reported daily usage was accounted for using industrial workplace standards. The variance across subjects was the smallest in the ear-canal measurements that were compensated for diffuse-field equivalence ͓ISO 11904-1 ͑2002͒, Switzerland͔. Seven subjects were found to be listening at levels above 85 dBA based on measurements obtained in the KEMAR and then compensated for diffuse-field equivalence.