Fig. 3.

Locomotor activity (mean number of beam interruptions per 10 min ± SEM; n = 8–10 per group) in a novel environment of sham-operated or neonatal MPFC-lesioned animals tested either at PD35 or PD56. Locomotor activity was determined as described in Materials and Methods. At PD35, lesioned animals did not differ from sham-operated animals at any testing interval. In contrast, at PD56, lesioned rats were more active than the sham-operated rats during the first 10 min of exploration (*p < 0.05).