Prefrontal and Auditory Input to Intercalated Neurons of the Amygdala

Cornelia Strobel; Roger Marek; Helen M Gooch; Robert K P Sullivan; Pankaj Sah

doi:10.1016/j.celrep.2015.02.008

Prefrontal and Auditory Input to Intercalated Neurons of the Amygdala

Cell Rep. 2015 Mar 10;10(9):1435-1442. doi: 10.1016/j.celrep.2015.02.008. Epub 2015 Mar 5.

Authors

Cornelia Strobel¹, Roger Marek¹, Helen M Gooch¹, Robert K P Sullivan¹, Pankaj Sah²

Affiliations

¹ The Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
² The Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia. Electronic address: pankaj.sah@uq.edu.au.

PMID: 25753409
DOI: 10.1016/j.celrep.2015.02.008

Abstract

The basolateral amygdala (BLA) and prefrontal cortex (PFC) are partners in fear learning and extinction. Intercalated (ITC) cells are inhibitory neurons that surround the BLA. Lateral ITC (lITC) neurons provide feed-forward inhibition to BLA principal neurons, whereas medial ITC (mITC) neurons form an inhibitory interface between the BLA and central amygdala (CeA). Notably, infralimbic prefrontal (IL) input to mITC neurons is thought to play a key role in fear extinction. Here, using targeted optogenetic stimulation, we show that lITC neurons receive auditory input from cortical and thalamic regions. IL inputs innervate principal neurons in the BLA but not mITC neurons. These results suggest that (1) these neurons may play a more central role in fear learning as both lITCs and mITCs receive auditory input and that (2) mITC neurons cannot be driven directly by the IL, and their role in fear extinction is likely mediated via the BLA.