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Updated: Jun 18, 2026

Ex Vivo Optogenetic Dissection of Fear Circuits in Brain Slices
Published on: April 5, 2016
Nuclear disconnection within the amygdala reveals a direct pathway to fear
Stephanie A Jimenez1, Stephen Maren
1Neuroscience Program, University of Michigan, Ann Arbor, Michigan 48109-1043, USA.
Abstract:
It is widely believed that a descending serial circuit consisting of neural projections from the basolateral complex (BLA) to the central nucleus (CEA) of the amygdala mediates fear expression. Here we directly test this hypothesis and show that disconnecting the BLA and CEA with asymmetric neurotoxic lesions after Pavlovian fear conditioning in rats completely abolishes the expression of conditional freezing. These results demonstrate that neural projections from the BLA to CEA are essential for the expression of learned fear responses.
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