Abstract:

Recently the term ``plasticity'' has been used in discussions of certain changes in human listeners' abilities to detect, discriminate, and identify simple and complex sounds. In some cases this appears to be merely an effort to use language appropriate to the Zeitgeist. To conclude that any specific neuroanatomical or neurophysiological change is responsible for improved or changed psychophysical performance requires that physiological measurements be made on the same subjects before and after the behavioral changes occur. That is rarely done. There are, however, useful contributions to the understanding of neural plasticity that might be made by a thorough study of the time course of auditory perceptual learning for various tasks and classes of stimuli. More relevant psychophysical data can be collected when long periods of training on a single psychophysical task are followed by tests on other tasks, making it possible to estimate the range of stimuli and tasks to which the learning has generalized. Studies meeting these criteria demonstrate great variation in the time course of auditory learning and in its specificity. [Prepared with the support of NIH/NIDCD.]