Genetics, septal lesions, and avoidance behavior in mice

Abstract

Frequently, physiological experiments fail to consider the genetic constitution of experimental subjects. The present series of experiments was designed to examine how strain of mouse interacts with brain damage on avoidance behavior. In a series of four experiments three strains of male mice (RF/J, C57BL/6J, and Binghamton-Heterogeneous (HET)) received either septal lesions or control surgery, and then were trained in avoidance tasks. In Experiment 1, the two-way active avoidance performance of both the C57 and HET lesion groups was superior to that of their respective controls. However, the RF lesion and control groups performed at almost identical levels. In Experiment 2, intertrial interval (ITI) shuttle responses were punished in the two-way active avoidance situation. Again, only the C57 and HET mice with septal lesions showed facilitated and improved two-way active avoidance behavior across days. RF lesion animals were initially superior to their control counterparts, but did not improve over days. Differential patterns of shuttle activity also were observed across the different strain and surgery groups. In Experiments 3 and 4, mice were trained on a step-through and water deprivation passive avoidance task, respectively. Mice with lesions were inferior to their control counterparts except that C57 mice with septal lesions were not deficient in performance relative to controls. The implications of genetic interactions with brain damage are discussed.