A circuit mechanism for differentiating positive and negative associations

The ability to differentiate stimuli predicting positive or negative outcomes is critical for survival, and perturbations of emotional processing underlie many psychiatric disease states. Synaptic plasticity in the basolateral amygdala complex (BLA) mediates the acquisition of associative memories,...

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Bibliographic Details
Main Authors: Namburi, Praneeth, Beyeler, Anna, Yorozu, Suzuko, Calhoon, Gwendolyn G., Wichmann, Romy, Holden, Stephanie S., Mertens, Kim L., Wickersham, Ian R., Gray, Jesse M., Halbert, Sarah, Anahtar, Melodi N., Felix-Ortiz, Ada Celis, Tye, Kay
Other Authors: Massachusetts Institute of Technology. Department of Biological Engineering
Format: Article
Language:en_US
Published: Nature Publishing Group 2016
Online Access:http://hdl.handle.net/1721.1/102520
https://orcid.org/0000-0003-2371-5706
https://orcid.org/0000-0002-1410-8675
https://orcid.org/0000-0003-0652-5652
https://orcid.org/0000-0002-4191-6926
https://orcid.org/0000-0002-4506-8813
Description
Summary:The ability to differentiate stimuli predicting positive or negative outcomes is critical for survival, and perturbations of emotional processing underlie many psychiatric disease states. Synaptic plasticity in the basolateral amygdala complex (BLA) mediates the acquisition of associative memories, both positive and negative. Different populations of BLA neurons may encode fearful or rewarding associations, but the identifying features of these populations and the synaptic mechanisms of differentiating positive and negative emotional valence have remained unknown. Here we show that BLA neurons projecting to the nucleus accumbens (NAc projectors) or the centromedial amygdala (CeM projectors) undergo opposing synaptic changes following fear or reward conditioning. We find that photostimulation of NAc projectors supports positive reinforcement while photostimulation of CeM projectors mediates negative reinforcement. Photoinhibition of CeM projectors impairs fear conditioning and enhances reward conditioning. We characterize these functionally distinct neuronal populations by comparing their electrophysiological, morphological and genetic features. Overall, we provide a mechanistic explanation for the representation of positive and negative associations within the amygdala.