Effects of electrical stimulation of rat limbic system and midbrain reticular formation upon short- and long-term memory

Rats were given electrical stimulation of the midbrain reticular formation, hippocampus or amygdala 4 sec after receiving a footshock contingent upon a barpress response. They were retested for memory of the shock 64 sec or 24 hr after the footshock. The animals that received midbrain reticular formation stimulation showed amnesia at 64-sec retest and memory at 24-hr retest. In contrast, animals that received hippocampal brain stimulation showed memory at 64-sec retest and amnesia at 24-hr retest. Animals that received amygdala brain stimulation showed amnesia at both 64-sec and 24-hr retest. The data support a dual parallel processing model of memory.