title: Perirhinal-hippocampal connectivity during reactivation is a marker for object-based memory consolidation.
abstract: The present study utilized event-related fMRI to address the role of the human perirhinal cortex (PRC), and its interactions with the hippocampus, in memory consolidation. Participants encoded object-based and scene-based associations and then restudied them either after a "long" or "short" delay during which consolidation could occur. We found that BOLD activation in left PRC and hippocampal-PRC functional connectivity were significantly enhanced during the restudy of the long versus short delay word-object pairs. Secondly, hippocampal-PRC connectivity during restudy of the long delay word-object pairs predicted a subsequent reduction in associative forgetting. By contrast, hippocampal-PRC connectivity did not predict subsequent resistance to forgetting for the short delay or novel associations. Together, these results provide evidence for perirhinal-hippocampal interactions in the selective consolidation of object-based associative memories and provide support for the notion that, during early stages of consolidation, memories become more distributed across brain regions.
authors.affiliation: Center for Vital Longevity and School of Behavioral and Brain Sciences, University of Texas, Dallas, 1600 Viceroy Drive, Suite 800, Dallas, TX 75235, USA.
authors.forename: Kaia L
authors.initials: KL
authors.lastname: Vilberg
authors.forename: Lila
authors.initials: L
authors.lastname: Davachi
mesh_terms: D000293:Adolescent; D000328:Adult; D001245:Association Learning / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply / Q000502:physiology*; D005260:Female; D006624:Hippocampus / Q000098:blood supply / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D009434:Neural Pathways / Q000098:blood supply / Q000502:physiology*; D010100:Oxygen; D010775:Photic Stimulation; D011597:Psychomotor Performance; D011930:Reaction Time; D014825:Vocabulary; D055815:Young Adult
chemical_list: D010100:Oxygen