Habituation: It's not what you think it is.

In this review, we take a critical look at the methods used to document habituation and the theoretical assumptions that have been made about it. We point out problems associated with measuring habituation merely as a change over the course of repeated presentations of a stimulus. We argue that a common test procedure is essential to assess the relative magnitudes of habituation learning especially when different training procedures are examined. We further suggest that this would be required in order to draw meaningful conclusions about the conditions for optimizing habituation. We also challenge the view that habituation is nonassociative and consider the implications of various associative learning perspectives not only for context-specific habituation but for encoding a representation of the stimulus. We conclude with our recommendations for future research on habituation and we highlight the need to integrate behavioral and neurobiological studies.