PMID- 11718885
DA - 20011123
DCOM- 20020111
IS - 0166-4328
VI - 127
IP - 1-2
DP - 2001 Dec 14
TI - Re-evaluation of the spatial memory deficits induced by hippocampal short lasting inactivation reveals the need for cortical co-operation.
PG - 71-9 AB - Evidence has accumulated that the rat hippocampus plays a central role in spatial memory. In complement to lesion studies, reversible lidocaine-induced inactivations have been used to investigate the time-course of the memory processes mediated by the hippocampus. A number of studies suggest that, in some conditions, the hippocampus is not necessary for online acquisition of spatial information. To test this hypothesis, we examined the effects of bilateral lidocaine-induced inactivations of the dorsal hippocampus in the acquisition of new spatial information. After initial learning of a place navigation task in the water maze, rats were tested for acquisition of a new platform location and received injections of lidocaine in the hippocampus prior to each daily four-trial block. The training blocks were separated by a 24-h period allowing the hippocampus to recover from inactivation. The results show that lidocaine-injected rats were able to learn the new platform location like controls. Inactivations, however, was found to induce a within-block learning impairment. This suggests that the hippocampus can perform off-line processing and that another structure is able to handle spatial information during hippocampal inactivations. Parietal-lesioned rats that received an injection of lidocaine were still able to learn the new platform location suggesting that the parietal cortex does not sustain this role. Overall, our results suggest that the hippocampus is not necessary for all stages of memory formation and co-operates with other brain, possibly cortical, structures which remain to be determined.
AD - Centre de Recherche en Neurosciences Cognitives (CRNC), Centre National de
la Recherche Scientifique (CNRS), 31 Chemin Joseph Aiguier, 13402
Marseille Cedex 20, France.
FAU - Parron, C
AU - Parron C
FAU - Poucet, B
AU - Poucet B
FAU - Save, E
AU - Save E
LA - eng
PT - Journal Article
CY - Netherlands
TA - Behav Brain Res
JID - 8004872
RN - 0 (Anesthetics, Local)
RN - 137-58-6 (Lidocaine)
SB - IM
MH - Anesthetics, Local/administration & dosage
MH - Animal
MH - Hippocampus/drug effects/*physiology
MH - Lidocaine/administration & dosage
MH - Memory/drug effects/*physiology
MH - Memory, Short-Term/physiology
MH - Models, Neurological
MH - Parietal Lobe/drug effects/*physiology
MH - Rats
MH - *Space Perception
MH - Time Factors
EDAT- 2001/11/24 10:00
MHDA- 2002/01/12 10:01
AID - S0166432801003576 [pii]
PST - ppublish
SO - Behav Brain Res 2001 Dec 14;127(1-2):71-9.