DIFFERENTIAL INVOLVEMENT OF THE RIGHT AND LEFT AMYGDALAE IN EXPRESSION OF MEMORY FOR AVERSIVELY MOTIVATED TRAINING

The present study investigated possible lateralization of amygdala inv olvement in memory for aversively motivated training. Rats with bilate ral cannulae aimed at the amygdalae were trained in a one-trial inhibi tory avoidance task. Twenty-four h or 10 days later, animals received bilateral pre-test microinjections of either vehicle, 2% lidocaine, or unilateral infusions of each simultaneously. Five min after the infus ions, retention was tested. Retention latencies of rats given bilatera l lidocaine or unilateral lidocaine into only the right amygdala were significantly lower than controls. These results suggest that the righ t and left amygdalae may make differential contributions to the expres sion of memory, and that the contribution of the right amygdala may be more important to the expression of memory for aversively motivated t raining.