[Improvement in the retrieval of a system of conditioned reflexes elaborated during rat ontogeny and administration of ACTH4-7].

A chain of two conditioned reflexes was elaborated in prepubertal rats from 2 to 6 weeks of age. Then the nature of amnesia was studied after an interval of 2 weeks. The system of motor food-procuring conditioned reflexes, disturbed by the interval was reestablished almost completely by ACTH4-7 administration before testing. A deficit of retrieval is supposed to be the cause of amnesia in prepubertal rats. Analysis of erroneous movements during the restoration of motor skill showed that information less essential for food getting suffered to a greater extent and it was not restored by ACTH4-7 administration. The retrieval disturbance did not depend on the degree of stability of the motor skill and the age of its acquisition.