Abstract:
Reaction time (RT) studies provide information about perceptual and post-perceptual information processing. A prior investigation found only small differences between the mean RTs of hearing-impaired (HI) and normal-hearing (NH) subjects performing a simple RT task with subjectively loud and soft tonal stimuli. The present study extended that group comparison to a choice RT task. Subjects with early-onset, moderate-to-severe sensorineural hearing impairments (N=8) and NH controls (N=14) made same--different judgments about digit pairs. In an auditory condition spoken digits were presented at two levels of loudness, representing the endpoints of a subject's dynamic range. In a visual condition digits were shown at the dimmest and brightest settings of a computer monitor. All subjects performed accurately in both modalities (>90% correct). Notable findings regarding RT were as follows: (1) The intensity variations had no significant effect for either group; (2) the two groups had comparable RTs in the visual condition; (3) the HI group was significantly slower in the auditory condition; and (4) subjects' auditory and visual performance were strongly correlated for the NH group but not for the HI group. Factors affecting group and individual differences will be discussed. [Work supported by NIH-NIDCD.]