STRAIN-DEPENDENT ESCAPE DEFICIT IN 2 RAT MODELS OF LEARNED HELPLESSNESS

The shuttle box escape deficit produced by prior inescapable shock (IS ) or by escapable shock (ES) was investigated in Koltushi high- (KHA) and low-avoidance (KLA) rat strains, genetically selected on the basis of divergent acquisition of a conditioned avoidance response in a two -way shuttle box. IS enhanced escape failures only in KHA rats. In con trast, ES produce escape deficit only in KLA rats. These data suggest that the learned helplessness interpretation of escape deficit might b e relevant only when IS is administered to KHA rats. In the case of KL A rats exposed to ES, escape deficit represents a coping behavior.