Habituation of the orienting reflex (OR) is typically treated as a kind of stimulus learning. Results of 3 experiments employing the GSR indicate, however, that (1) stimuli which have behavioral associates produce greater ORs than those which do not; (2) new behavioral associations produce greater ORs than old associations, i.e., selective habituation occurs to response characteristics; and (3) level of ORs across habituation trials is a direct function of the amount of response information to be encoded. It appears that the neuronal model of a stimulus includes the characteristics of associated responses. (PsycINFO Database Record (c) 2006 APA, all rights reserved)