Abstract
Single-cell activity was recorded in the dorsal subnucleus of the lateral amygdala (LAd) of freely behaving rats during Pavlovian fear conditioning, to determine the relationship between neuronal activity and behavioral learning. Neuronal responses elicited by the conditioned stimulus typically increased before behavioral fear was evident, supporting the hypothesis that neural changes in LAd account for the conditioning of behavior. Furthermore, two types of these rapidly modified cells were found. Some, located in the dorsal tip of LAd, exhibited short-latency responses (<20 ms) that were only transiently changed. A second class of cells, most commonly found in ventral regions of LAd, had longer latency responses, but maintained enhanced responding throughout training and even through extinction. These anatomically distinct cells in LAd may be differentially involved in the initiation of learning and long-term memory storage.
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Acknowledgements
This research was supported in part by NIH grants RO1 MH46516, KO2 MH00956, R37 MH38774 and F31 MH11659. The work was also supported by a grant from the W.M. Keck Foundation to N.Y.U.
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Repa, J., Muller, J., Apergis, J. et al. Two different lateral amygdala cell populations contribute to the initiation and storage of memory. Nat Neurosci 4, 724–731 (2001). https://doi.org/10.1038/89512
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DOI: https://doi.org/10.1038/89512
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