Learning twice is different from learning once and from learning more.
The rat hippocampus plays a crucial role in the consolidation of a variety of memories, including that for a one trial inhibitory avoidance learning task in which stepping down from a platform is associated with a footshock. Here we show that this is the case regardless of the intensity of the footshock used and hence, of the strength of the learned response. However, additional learning produced by a second training session in this task does not involve the hippocampus but, instead, the striatum. Memory consolidation of the second trial requires glutamate alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate, N-methyl-D-aspartate and metabotropic receptors, activation of signaling pathways, gene expression and protein synthesis in the striatum, as are required in the hippocampus during memory consolidation of the first trial.
Cammarota
M
M
Laboratorio de Neuroreceptores, Instituto de Biología Celular y Neurociencias Prof. Dr. Eduardo de Robertis, Facultad de Medicina, Universidad de Buenos Aires, Paraguay, Ciudad Autónoma de Buenos Aires CP 1121, Argentina.
Bevilaqua
L R M
LR
Köhler
C
C
Medina
J H
JH
Izquierdo
Iván
I
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001522:Behavior, Animal; D001596:Benzylamines / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000502:physiology*; D004004:Dichlororibofuranosylbenzimidazole / Q000494:pharmacology; D004597:Electroshock / Q000009:adverse effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005108:Extinction, Psychological / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007858:Learning / Q000187:drug effects / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D011810:Quinoxalines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000502:physiology; D012153:Retention, Psychology / Q000187:drug effects*; D018709:Statistics, Nonparametric; D013449:Sulfonamides / Q000494:pharmacology; D013997:Time Factors; D014633:Valine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000096926:Benzenesulfonamides
D001596:Benzylamines; D004004:Dichlororibofuranosylbenzimidazole; D004791:Enzyme Inhibitors; D018691:Excitatory Amino Acid Antagonists; D011810:Quinoxalines; D016194:Receptors, N-Methyl-D-Aspartate; D013449:Sulfonamides; D014633:Valine; C072105:KN 93; D000096926:Benzenesulfonamides; C056723:FG 9041; C056639:2-amino-5-phosphopentanoic acid