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Title: Contributions of site- and sex-specific LTPs to everyday memory
Commentaries about long-term potentiation (LTP) generally proceed with an implicit assumption that largely the same physiological effect is sampled across different experiments. However, this is clearly not the case. We illustrate the point by comparing LTP in the CA3 projections to CA1 with the different forms of potentiation in the dentate gyrus. These studies lead to the hypothesis that specialized properties of CA1-LTP are adaptations for encoding unsupervised learning and episodic memory, whereas the dentate gyrus variants subserve learning that requires multiple trials and separation of overlapping bodies of information. Recent work has added sex as a second and somewhat surprising dimension along which LTP is also differentiated. Triggering events for CA1-LTP differ between the sexes and the adult induction threshold is significantly higher in females; these findings help explain why males have an advantage in spatial learning. Remarkably, the converse is true before puberty: Females have the lower LTP threshold and are better at spatial memory problems. A mechanism has been identified for the loss-of-function in females but not for the gain-of-function in males. We propose that the many and disparate demands of natural environments, with different processing requirements across ages and between sexes, led to the emergence of multiple LTPs. This article is part of a discussion meeting issue ‘Long-term potentiation: 50 years on’.  more » « less
Award ID(s):
1941216
PAR ID:
10526237
Author(s) / Creator(s):
; ;
Publisher / Repository:
The Royal Society Pubmishing
Date Published:
Journal Name:
Philosophical Transactions of the Royal Society B: Biological Sciences
Volume:
379
Issue:
1906
ISSN:
0962-8436
Subject(s) / Keyword(s):
Long-term potentiation synaptic plasticity dentate gyrus CA1 learning episodic memory
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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