Reversible inactivation of hippocampus and dorsolateral striatum in C57BL/6 and DBA/2 inbred mice failed to show interaction between memory systems in these genotypes.
C57BL/6 and DBA/2 mice with cannulae inserted bilaterally in the dorsal hippocampus or the dorsolateral striatum were released from the south arm of a cross maze and trained to find food in the east arm. Probe trials on which mice were released from the north arm were given following short or prolonged training. Prior to the probe trials, mice received intra-hippocampal or intra-striatal injections of lidocaine or saline. Results show that saline-injected C57BL/6 were fundamentally place learners whereas saline-injected DBA/2 mice did not engage any predominant system. Inactivating the hippocampus or the dorsolateral striatum in C56BL/6 mice disrupted place learning without promoting response learning. Inactivating the same brain sites in DBA/2 mice did not affect their behaviour. Thus, contrary to that observed in rats, disrupting the neural substrate of one memory system can abolish learning in that system but does not promote the use of another system in these genotypes.
CNR Institute of Neuroscience, Laboratory of Psychobiology and Psychopharmacology, IRCCS S. Lucia Foundation, Via Ardeatina 306, 00179 Rome, Italy.
Silvia
S
Middei
Leonardo
L
Restivo
Carmelo
C
Sgobio
Enrica
E
Passino
Martine
M
Ammassari-Teule
D000704:Analysis of Variance; D000779:Anesthetics, Local / Q000009:adverse effects*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D003342:Corpus Striatum / Q000187:drug effects* / Q000502:physiology; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D008012:Lidocaine / Q000009:adverse effects*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008568:Memory / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D013037:Spatial Behavior / Q000187:drug effects; D013045:Species Specificity; D013997:Time Factors
D000779:Anesthetics, Local; D008012:Lidocaine