Clustered c-Fos Activation in Rat Hippocampus at the Acquisition Stage of Appetitive Instrumental Learning

作     者：Olga E. Svarnik Yuri I. Alexandrov Konstantin V. Anokhin 

作者机构：Institute of Psychology Russian Academy of Sciences Moscow Russia Department of Neuroscience National Research Center “Kurchatov Institute” Moscow Russia P. K. Anokhin Institute of Normal Physiology Russian Academy of Medical Sciences Moscow Russia 

出 版 物：《Journal of Behavioral and Brain Science》 (行为与脑科学期刊（英文）)

年 卷 期：2015年第5卷第3期

页      面：69-80页

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：Fos Hippocampus Clusters Neuron Learning 

摘      要：To address the issue of how hippocampal neurons are involved into learning progress, we studied c-Fos expression in rat hippocampal subfields at different stages of appetitive instrumental learning. To model the first stage of learning, we pre-trained animals to approach the lever to obtain the food, and then made this behavior ineffective by not reinforcing it during the last session (“mismatch group). Another group just acquired lever-pressing behavior at that day (“acquisition group). Animals of the third group performed this well-trained behavior (“performance group). The number of Fos-positive neurons in all hippocampal regions of the “mismatch group animals was higher than in the ones of the home cage control group animals. The number of Fos-positive neurons was increased in CA1 and CA3 areas, but not in the dentate gyrus of both the “acquisition and “performance group animals as compared with the control group. We also found segmented c-Fos expression, which was more evident in “acquisition group animals. Thus, our results suggest that during the first (mismatch) stage of learning hippocampal neurons are activated in an equally distributed manner. The following clustered pattern of activated CA1 neurons during the acquisition stage may reflect specialization of these neurons in respect to the specific lever-pressing behavior.