Abstract
How sensory information is transformed by learning into adaptive behaviors is a fundamental question in neuroscience. Studies of auditory fear conditioning have revealed much about the formation and expression of emotional memories and have provided important insights into this question. Classical work focused on the amygdala as a central structure for fear conditioning. Recent advances, however, have identified new circuits and neural coding strategies mediating fear learning and the expression of fear behaviors. One area of research has identified key brain regions and neuronal coding mechanisms that regulate the formation, specificity and strength of fear memories. Other work has discovered critical circuits and neuronal dynamics by which fear memories are expressed through a medial prefrontal cortex pathway and coordinated activity across interconnected brain regions. Here we review these recent advances alongside prior work to provide a working model of the extended circuits and neuronal coding mechanisms mediating fear learning and memory.
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Acknowledgements
We thank T.C. Bienvenu, R.R. Rozeske and J. Ormond for helpful comments on the manuscript. This work was supported by grants to C.H. from the French National Research Agency (ANR-2010-BLAN-1442-01; ANR-10-EQPX-08 OPTOPATH; LABEX BRAIN ANR 10-LABX-43), the European Research Council under the European Union's Seventh Framework Program (FP7/2007-2013)/ERC grant agreement no. 281168, the Conseil Regional d'Aquitaine, and by grants to J.P.J. from MEXT (Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS)), Strategic Research Program for Brain Sciences (11041047) and Grants-in-Aid for Scientific Research (25710003, 25116531).
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Herry, C., Johansen, J. Encoding of fear learning and memory in distributed neuronal circuits. Nat Neurosci 17, 1644–1654 (2014). https://doi.org/10.1038/nn.3869
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