Protective effect of under-reinforcement of passive avoidance against scopolamine-induced amnesia.
Administration of antimuscarinic drugs induces amnesia of aversively motivated behaviors. However, when relatively high intensities of footshock are used during training (over-reinforcement), animals become protected against such amnesic state. Moreover, the protective effect is established in a none-or-all fashion, i.e., within a series of increasing intensities a minute augmentation of footshock intensity is sufficient to reach the protective threshold. In the present experiment it was found that very low intensities of aversive stimulation (under-reinforcement), sufficient to produce learning, also protected animals from scopolamine-induced amnesia. These results suggest that acetylcholine is critically involved in memory consolidation of passive avoidance, but only within a limited range of training intensities.
Quirarte
G L
GL
Facultad de Psicología, Universidad de Guadalajara, México.
Cruz-Morales
S E
SE
Diaz del Guante
M A
MA
Garcia
M
M
Prado-Alcalá
R A
RA
D000647:Amnesia / Q000139:chemically induced / Q000523:psychology*; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D008297:Male; D018727:Muscarinic Antagonists; D051381:Rats; D017208:Rats, Wistar; D012055:Reinforcement Schedule; D012601:Scopolamine
D018727:Muscarinic Antagonists; D012601:Scopolamine