Habituation and retention of habituation in the leech (Macrobdella decora).

Abstract

Studied habituation of movement responses by 20 leeches in 2 experiments using light onset and water current as stimuli. Ss habituated to light onset and retained habituation for at least 2 successive 24-hr periods. Habituation to water current was influenced in the expected way by ITI. Ss habituated in fewer trials with a 30-sec ITI than with a 60-sec ITI. Response facilitation appeared early in habituation in both experiments and is discussed in terms of sensitization and response interference. Base rates of responding in the absence of specific eliciting stimuli were zero. Results are considered in terms of generality of processes associated with habituation and previous findings with species of annelids. (PsycINFO Database Record (c) 2006 APA, all rights reserved)