Cortico-hippocampal Schemas Enable NMDAR-Independent Fear Conditioning in Rats.

Autor:	Finnie PSB; Psychology Department, McGill University, 1205 Avenue Drive Penfield, Montreal, QC H3A 1B1, Canada., Gamache K; Psychology Department, McGill University, 1205 Avenue Drive Penfield, Montreal, QC H3A 1B1, Canada., Protopoulos M; Psychology Department, McGill University, 1205 Avenue Drive Penfield, Montreal, QC H3A 1B1, Canada., Sinclair E; Psychology Department, McGill University, 1205 Avenue Drive Penfield, Montreal, QC H3A 1B1, Canada., Baker AG; Psychology Department, McGill University, 1205 Avenue Drive Penfield, Montreal, QC H3A 1B1, Canada., Wang SH; Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building GU507c, Edinburgh EH16 4SB, UK. Electronic address: s.wang@ed.ac.uk., Nader K; Psychology Department, McGill University, 1205 Avenue Drive Penfield, Montreal, QC H3A 1B1, Canada. Electronic address: karim.nader@mcgill.ca.
Jazyk:	angličtina
Zdroj:	Current biology : CB [Curr Biol] 2018 Sep 24; Vol. 28 (18), pp. 2900-2909.e5. Date of Electronic Publication: 2018 Sep 06.
DOI:	10.1016/j.cub.2018.07.037
Abstrakt:	The neurobiology of memory formation has been studied primarily in experimentally naive animals, but the majority of learning unfolds on a background of prior experience. Considerable evidence now indicates that the brain processes initial and subsequent learning differently. In rodents, a first instance of contextual fear conditioning requires NMDA receptor (NMDAR) activation in the dorsal hippocampus, but subsequent conditioning to another context does not. This shift may result from a change in molecular plasticity mechanisms or in the information required to learn the second task. To clarify how related events are encoded, it is critical to identify which aspect of a first task engages NMDAR-independent learning and the brain regions that maintain this state. Here, we show in rats that the requirement for NMDARs in hippocampus depends neither on prior exposure to context nor footshock alone but rather on the procedural similarity between two conditioning tasks. Importantly, NMDAR-independent learning requires the memory of the first task to remain hippocampus dependent. Furthermore, disrupting memory maintenance in the anterior cingulate cortex after the first task also reinstates NMDAR dependency. These results reveal cortico-hippocampal interactions supporting experience-dependent learning. (Copyright © 2018 Elsevier Ltd. All rights reserved.)
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu