Medial prefrontal-perirhinal cortical communication is necessary for flexible response selection

Neurobiol Learn Mem. 2017 Jan:137:36-47. doi: 10.1016/j.nlm.2016.10.012. Epub 2016 Nov 1.

Abstract

The ability to use information from the physical world to update behavioral strategies is critical for survival across species. The prefrontal cortex (PFC) supports behavioral flexibility; however, exactly how this brain structure interacts with sensory association cortical areas to facilitate the adaptation of response selection remains unknown. Given the role of the perirhinal cortex (PER) in higher-order perception and associative memory, the current study evaluated whether PFC-PER circuits are critical for the ability to perform biconditional object discriminations when the rule for selecting the rewarded object shifted depending on the animal's spatial location in a 2-arm maze. Following acquisition to criterion performance on an object-place paired association task, pharmacological blockade of communication between the PFC and PER significantly disrupted performance. Specifically, the PFC-PER disconnection caused rats to regress to a response bias of selecting an object on a particular side regardless of its identity. Importantly, the PFC-PER disconnection did not interfere with the capacity to perform object-only or location-only discriminations, which do not require the animal to update a response rule across trials. These findings are consistent with a critical role for PFC-PER circuits in rule shifting and the effective updating of a response rule across spatial locations.

Keywords: Entorhinal cortex; Executive functions; Functional connectivity; Hippocampus; Memory.

MeSH terms

  • Animals
  • Association Learning / drug effects
  • Association Learning / physiology*
  • Executive Function / drug effects
  • Executive Function / physiology*
  • GABA-A Receptor Agonists / pharmacology
  • Male
  • Muscimol / pharmacology
  • Neural Pathways / drug effects
  • Neural Pathways / physiology
  • Perirhinal Cortex / drug effects
  • Perirhinal Cortex / physiology*
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / physiology*
  • Rats
  • Rats, Inbred F344
  • Spatial Learning / drug effects
  • Spatial Learning / physiology*

Substances

  • GABA-A Receptor Agonists
  • Muscimol