Dendritic Inhibition in the Hippocampus Supports Fear Learning

Abstract

Fear, Memory, and Place Contextual fear conditioning (CFC) is widely used as a hippocampal-dependent classical conditioning task to model human episodic memory. Lovett-Barron et al. (p. 857 ) combined in vivo imaging with pharmacology, pharmacogenetics, and optogenetics and they found that somatostatin-expressing, dendrite-targeting γ-aminobutyric acid–releasing interneurons in hippocampal area CA1 are required for CFC. During CFC, sensory features of the aversive event reach hippocampal output neurons through excitatory cortical afferents and require active inhibitory filtering to ensure that the hippocampus exclusively encodes the conditioned stimulus.