Persistence of retrieval enhancement by amphetamine following scopolamine-induced amnesia.
Little information is available on the permanence of pharmacologically-induced retrieval enhancement following amnesia. This was studied by comparing the rate of forgetting of a memory reactivated by d-amphetamine after amnesia with spontaneous forgetting of undisturbed fear conditioning. Mice were treated with either saline or scopolamine before conditioning and retention was tested three days later. Scopolamine-treated mice received either saline or amphetamine before testing while the saline controls received a second saline injection. The scopolamine-saline group exhibited robust amnesia, whereas both saline-saline and scopolamine-amphetamine groups showed good retention. To test the persistence of these effects mice in the three groups were subdivided and given a second retention test either 1 day, 1 week or 1 month after the first test. Amphetamine was not administered before the second test. The scopolamine-saline mice continued to exhibit amnesia for up to 1 month while the scopolamine-amphetamine and saline-saline groups continued to show strong memory with only a modest decrement in performance by 1 month after the first test. These results show that amphetamine results in a permanent recovery from scopolamine amnesia.
Quartermain
D
D
Department of Neurology, New York University School of Medicine, NY.
Jung
H
H
D000647:Amnesia / Q000139:chemically induced* / Q000523:psychology; D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects; D003913:Dextroamphetamine / Q000494:pharmacology*; D008297:Male; D008568:Memory / Q000187:drug effects*; D051379:Mice; D012601:Scopolamine
D012601:Scopolamine; D003913:Dextroamphetamine