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Two different lateral amygdala cell populations contribute to the initiation and storage of memory

Nature Neuroscience volume 4, pages 724–731 (2001)Cite this article

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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Figure 1: Behavioral measures of conditioned fear.
Figure 2: Photomicrograph of a thionin-stained brain section from a representative rat, showing electrode tract and lesion site in LAd.
Figure 3: Neuronal plasticity during early extinction, for all cells.
Figure 4: Neuronal plasticity during conditioning, for all cells.
Figure 5: Latency and time course of neuronal plasticity.
Figure 6: Acquisition of neuronal versus behavioral measures of learning.
Figure 7: Persistence of neuronal plasticity during conditioning.
Figure 8: Breakdown of transiently plastic versus long-lasting plastic cells, by latency of plasticity and anatomical location.

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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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  1. W.M. Keck Foundation Laboratory of Neurobiology, Center for Neural Science, New York University, 4 Washington Place, Room 809, New York, 10003, New York, USA

    J. Christopher Repa, Jeff Muller, John Apergis, Theresa M. Desrochers, Yu Zhou & Joseph E. LeDoux

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Correspondence to J. Christopher Repa.

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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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