1993 Volume 36 Issue 6 Pages 751-756
Reaction time and response accuracy under a two-tone discrimination (odd ball) task were measured in nine cochlear implant recipients. The age of the subjects ranged from 17 to 70 and the mean was 53.7 years. Two different pitch tones were offered to the subject in random order. When the stimulus was rare-target, the subject was asked to lift of the thumb finger. Frequent-nontarget tones was 1000Hz, wheres the rare-target tones were 2000Hz, 1500Hz or 1200Hz tone during each block. As the result, the recipients decreased an ability to pitch detection. The avaraged reaction time was 382ms and the response accuracy was 91.7% when the rare tone was 2000Hz. When the frequency of target tone became closer to the frequent tone, the false response and reaction time increased significantly (P<0.05, t-test). There was a great inter-individual difference in the ability of frequency discrimination. The response accuracy showed significant correlation with the score of the speech tracking test (p<0.05). These data suggest that this measure may be useful in assessing their auditory discrimination ability.