Analyzing the role of adult hippocampal neurogenesis in contextual fear conditioning

Abstract

Event Abstract Back to Event Analyzing the role of adult hippocampal neurogenesis in contextual fear conditioning Michael R. Drew1*, Christine A. Denny1 and Rene Hen1 1 Columbia University, Department of Psychiatry, United States Recent studies suggest that adult hippocampal neurogenesis is required for contextual fear conditioning, a form of Pavlovian conditioning in which a spatial context is paired with an aversive stimulus such as footshock. Rodents in which adult neurogenesis was arrested acquired less fear of the shock-paired context than did controls, suggesting that adult-born hippocampal neurons are integral to context memory and/or other aspects of associative learning. However, the validity of this finding is questioned by other recent studies that failed to detect effects of arresting neurogenesis on contextual fear conditioning. In hopes of resolving the discrepancy, we evaluated the generality of contextual fear conditioning deficits induced by low-dose, targeted irradiation in mice, which produces a complete and lasting ablation of hippocampal neurogenesis, while sparing other neurogenic niches. We found that 1-trial contextual fear conditioning was more sensitive to the arrest of neurogenesis than was multiple-trial conditioning. In addition, deficits in 1-trial contextual fear conditioning were rescued when mice were provided with extra exposure to the conditioning context prior to training. The results suggest that neurogenesis is required only in procedures that demand rapid encoding of contextual information. The behavioral effects of irradiation were also highly time-dependent. The impairment in contextual fear conditioning was absent 2 weeks post-irradiation, suggesting that very young adult-born neurons are not required for this form of learning. By 6 weeks post-irradiation a significant impairment had appeared, but at 8 and 10 weeks post-irradiation, the impairment disappeared, suggesting that over time the brain compensates for the loss of adult neurogenesis. Our results suggest that contextual fear conditioning is sensitive to the arrest of adult neurogenesis, but only when the conditioning procedure demands rapid learning and is conducted within a limited window of time after the arrest of neurogenesis. Conference: 41st European Brain and Behaviour Society Meeting, Rhodes Island, Greece, 13 Sep - 18 Sep, 2009. Presentation Type: Oral Presentation Topic: Symposia lectures Citation: Drew MR, Denny CA and Hen R (2009). Analyzing the role of adult hippocampal neurogenesis in contextual fear conditioning. Conference Abstract: 41st European Brain and Behaviour Society Meeting. doi: 10.3389/conf.neuro.08.2009.09.022 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 04 Jun 2009; Published Online: 04 Jun 2009. * Correspondence: Michael R Drew, Columbia University, Department of Psychiatry, New York, United States, mrd001@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Michael R Drew Christine A Denny Rene Hen Google Michael R Drew Christine A Denny Rene Hen Google Scholar Michael R Drew Christine A Denny Rene Hen PubMed Michael R Drew Christine A Denny Rene Hen Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.