DIFFERENTIAL EFFECTS OF HIPPOCAMPAL LESIONS UPON SEQUENTIAL TASKS AND MAZE LEARNING BY RAT

The performance of 19 male hooded Long-Evans rats with hippocampal lesions, neocortically ablated controls, and unoperated controls was compared by 2 measures designed to test the generality of perseveration interpretations of hippocampal-lesion effects. A 3rd measure was undertaken to clarify the nature of the deficit shown in a complex maze by rats with hippocampal lesions. The Ss with hippocampal damage learned to alternate lever pressing and other complex patterns of lever pressing more rapidly than did controls. When compared to controls in a Lashley-III maze, Ss with hippocampal lesions made significantly more errors which involved failure to turn into a door, but made no more errors of turning in the wrong direction. The results are interpreted as contrary to a completely strict response-perseveration explanation of hippocampal-lesion effects. (16 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.