Comparative effects of septo-hippocampal and caudate lesions on avoidance behavior in rats.

Abstract

LARGE BILATERAL HIPPOCAMPAL LESIONS PRODUCED THE SAME STABLE PATTERN OF EFFECTS AS SEPTAL LESIONS IN INCREASING SPONTANEOUS SHUTTLING AND IN FACILITATING DEVELOPMENT OF AVOIDANCE IN THE 2-WAY SHUTTLE BOX; IN BOTH CASES FACILITATION WAS ASSOCIATED WITH INCREASED INTERTRIAL ACTIVITY, REFLECTING REDUCTION IN FREEZING RESPONSES. LESS EXTENSIVE HIPPOCAMPAL DAMAGE REPRODUCED THE PATTERN, EXCEPT FOR INCREASED SPONTANEOUS ACTIVITY. FACILITATION IN AVOIDANCE AND ASSOCIATED REDUCTION IN FREEZING REFLECT DYSFUNCTIONS OF A COMMON SEPTO-HIPPOCAMPAL SYSTEM. ENHANCED REACTIVITY TO PHOTIC STIMULI, MORE CLOSELY LINKED TO SEPTAL DYSFUNCTION, COULD BE DISSOCIATED FROM OTHER PHENOMENA. CAUDATE AND NEOCORTICAL LESIONS, BY CONTRAST, IMPAIRED AVOIDANCE BEHAVIOR. (17 REF.) (PsycINFO Database Record (c) 2006 APA, all rights reserved)