Memory impairment after incomplete pharmacological kindling

Abstract

In rats trained to run for food reinforcement, kindling was reproduced by daily injections of subconvulsant doses of picrotoxin until the stage of recurrent clonic seizures. Subsequent behavioral test revealed no difference between kindled and control rats in retention and retrieval of memory traces. However these groups differed significantly in the dynamics and pattern of extinction: kindled animals needed much more time to stop running under conditions of non-reinforcement. A relearning test showed that kindling did not affect learning ability. Weakened inhibition after incomplete pharmacological kindling is indicative of a congnitive dysfunction characteristic of early stages of epilepsy.