Time course of auditory perceptual learning.

The time course of auditory perceptual learning can vary from one hour to more than a year, depending on the task, the complexity of the sounds, and the level of stimulus uncertainty under which the tasks are learned. Previous studies are reviewed which show that longer training is required to identify sounds than to discriminate between them, while the least time-consuming task is to learn to detect a sound's presence. The time course of each of these tasks is greatly extended for complex sounds compared to those for single tones. The learning of a speech-like code would thus be expected to require longer training than the employed in previous psychoacoustic research. The consequences of this fact for the exploitation of residual hearing are briefly discussed.