Impairment of active avoidance in rats with unilateral hypothalamic lesion.

Male albino rats with unilateral hypothalamic (ULH) lesion on either the right or left side were trained to acquire active shock avoidance in a two-way shuttle box. With 20 trials in a session per day, either group scored responses below 50% by the 8th day, while intact rats attained the criterion of 80% correct responses by the 5th day. It is concluded that intact lateral hypothalamic areas are essential for successful learning of active shock avoidance.