Local rates of cerebral glucose utilization (LCGU) were determined in adult rats submitted to electroconvulsive shock (ECS) treatment. One group of rats (n = 5) received a single ECS, a second group (n = 5) was treated once daily for 7 days. A third group (n = 5) of unshocked rats served as control. LCGU measurements were performed one day after either the single or the last ECS. Following a single ECS, most of the 45 brain regions examined exhibited lower rates of LCGU than controls, in contrast after repeated ECS treatment the metabolic activity results increased in segments of the hippocampus. The results indicate that repeated ECS treatment selectively increases metabolic rates within the hippocampus, a structure of the limbic system thought to be related to affective disorders and memory.