Failure of interocular transfer in two types of learning in the crab Chasmagnathus

Abstract

Crabs (Chasmagnathus granulatus) were trained monocularly and then tested after 24 h, in order to study interocular transfer (IOT) in two habituation paradigms. 1) Habituation of the escape response to an iterated visual danger stimuli. Monocular crabs exhibited retention after 24 h when trained and tested with the same uncovered eye, but not with different uncovered eyes. 2) Habituation of the exploratory activity to a novel environment. This long term habituation of the exploratory activity is exhibited after 24 h in monocular animals trained and tested with the same uncovered eye but not with different uncovered eyes. An explanation of this failure of IOT will be discussed in terms of retrieval impairment due to a) a different perception of training and testing stimuli, b) lateralization of memory storage, or c) the existence of two symmetrical, independent and redundant lateral storage sites.