4.3 Article

Dorsal hippocampus is necessary for novel learning but sufficient for subsequent similar learning

Journal

HIPPOCAMPUS
Volume 22, Issue 11, Pages 2157-2170

Publisher

WILEY
DOI: 10.1002/hipo.22036

Keywords

consolidation; voltage-dependent calcium channel blocker; GABA receptor agonist; protein synthesis inhibition; NMDA receptor antagonist

Categories

Funding

  1. NSERC [RGPIN 249880-11]
  2. CIHR [MOP-74672]
  3. CFI [9527]
  4. Caledonian Research Fellowship (Royal Society of Edinburgh, UK)
  5. EWR Steacie Fellow
  6. William Dawson Chair

Ask authors/readers for more resources

Our current understanding of brain mechanisms involved in learning and memory has been derived largely from studies using experimentally naive animals. However, it is becoming increasingly clear that not all identified mechanisms may generalize to subsequent learning. For example, N-methyl-D-aspartate glutamate (NMDA) receptors in the dorsal hippocampus are required for contextual fear conditioning in naive animals but not in animals previously trained in a similar task. Here we investigated how animals learn contextual fear conditioning for a second timea response which is not due to habituation or generalization. We found that dorsal hippocampus infusions of voltage-dependent calcium channel blockers or the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) agonist impaired the first, not the second contextual learning. Only manipulations of the entire hippocampus led to an impairment in second learning. Specifically, inactivation of either the dorsal or ventral hippocampus caused the remaining portion of the hippocampus to acquire and consolidate the second learning. Thus, dorsal hippocampus seems necessary for initial contextual fear conditioning, but either the dorsal or ventral hippocampus is sufficient for subsequent conditioning in a different context. Together, these findings suggest that prior training experiences can change how the hippocampus processes subsequent similar learning. (c) 2012 Wiley Periodicals, Inc.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.3
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available