Cholinergic transmission in the dorsal hippocampus modulates trace but not delay fear conditioning.


Journal Article

Although cholinergic mechanisms have been widely implicated in learning and memory processes, few studies have investigated the specific contribution of hippocampal cholinergic transmission during trace fear conditioning, a form of associative learning involving a temporal gap between two stimuli. Microinfusions of scopolamine, a muscarinic receptor antagonist, into the dorsal hippocampus (DH) produced dose-dependent impairment in the acquisition and expression of a conditioned response (CR) following trace fear conditioning with a tone conditioned stimulus (CS) and a footshock unconditioned stimulus (US) in rats. The same infusions, however, had no effect on delay conditioning, general activity, pain sensitivity or attentional modulation. Moreover, scopolamine infusions attenuated phosphorylation of extracellular signal-regulated kinase (ERK) in the amygdala, indicating that cholinergic signals in the DH are important for trace fear conditioning. Taken together, the current study provides evidence that cholinergic neurotransmission in the DH is essential for the cellular processing of CS-US association in the amygdala when the two stimuli are temporally disconnected.

Full Text

Duke Authors

Cited Authors

  • Pang, M-H; Kim, N-S; Kim, I-H; Kim, H; Kim, H-T; Choi, J-S

Published Date

  • September 2010

Published In

Volume / Issue

  • 94 / 2

Start / End Page

  • 206 - 213

PubMed ID

  • 20685338

Pubmed Central ID

  • 20685338

Electronic International Standard Serial Number (EISSN)

  • 1095-9564

International Standard Serial Number (ISSN)

  • 1074-7427

Digital Object Identifier (DOI)

  • 10.1016/j.nlm.2010.05.008


  • eng