Three remarks on perceptual learning.

This essay makes three points. (1) From the failure of perceptual learning to transfer when stimulus parameters are changed, it cannot necessarily be concluded that the site of learning is distal: rather, the learning may be central and the specificity may lie in what is learnt. (2) Mere exposure to a stimulus may not be sufficient for learning: even in the absence of explicit feedback, other sources of information are often available in a perceptual learning task. (3) Procedural learning may sometimes be apparent only after a delay: this phenomenon has a long history and is known as reminiscence.