title: A neural circuit for memory specificity and generalization.
abstract: Increased fear memory generalization is associated with posttraumatic stress disorder, but the circuit mechanisms that regulate memory specificity remain unclear. Here, we define a neural circuit-composed of the medial prefrontal cortex, the nucleus reuniens (NR), and the hippocampus-that controls fear memory generalization. Inactivation of prefrontal inputs into the NR or direct silencing of NR projections enhanced fear memory generalization, whereas constitutive activation of NR neurons decreased memory generalization. Direct optogenetic activation of phasic and tonic action-potential firing of NR neurons during memory acquisition enhanced or reduced memory generalization, respectively. We propose that the NR determines the specificity and generalization of memory attributes for a particular context by processing information from the medial prefrontal cortex en route to the hippocampus.
authors.affiliation: Department of Molecular and Cellular Physiology and Howard Hughes Medical Institute, Stanford University, Stanford, CA 94304-5453, USA. weixu@stanford.edu
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Südhof
mesh_terms: D000818:Animals; D001931:Brain Mapping; D000229:Dependovirus; D005239:Fear / Q000502:physiology*; D005793:Generalization, Psychological; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006624:Hippocampus / Q000502:physiology; D008297:Male; D008568:Memory / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D020644:Midline Thalamic Nuclei / Q000502:physiology; D009434:Neural Pathways; D017397:Prefrontal Cortex / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D050988:Vesicle-Associated Membrane Protein 2 / Q000235:genetics / Q000378:metabolism
chemical_list: D050988:Vesicle-Associated Membrane Protein 2; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins