Chronic stress impairs prefrontal cortex-dependent response inhibition and spatial working memory

Agnieszka Mika, Gabriel J. Mazur, Ann N. Hoffman, Joshua S. Talboom, Heather Bimonte-Nelson, Federico Sanabria, Cheryl Conrad

Research output: Contribution to journalArticlepeer-review

78 Scopus citations

Abstract

Chronic stress leads to neurochemical and structural alterations in the prefrontal cortex (PFC) that correspond to deficits in PFC-mediated behaviors. The present study examined the effects of chronic restraint stress on response inhibition (using a response-withholding task, the fixed-minimum interval schedule of reinforcement, or FMI), and working memory (using a radial arm water maze, RAWM). Adult male Sprague-Dawley rats were first trained on the RAWM and subsequently trained on FMI. After acquisition of FMI, rats were assigned to a restraint stress (6h/d/28d in wire mesh restrainers) or control condition. Immediately after chronic stress, rats were tested on FMI and subsequently on RAWM. FMI results suggest that chronic stress reduces response inhibition capacity and motivation to initiate the task on selective conditions when sucrose reward was not obtained on the preceding trial. RAWM results suggest that chronic stress produces transient deficits in working memory without altering previously consolidated reference memory. Behavioral measures from FMI failed to correlate with metrics from RAWM except for one in which changes in FMI timing imprecision negatively correlated with changes in RAWM working memory errors for the controls, a finding that was not observed following chronic stress. Fisher's r-to-z transformation revealed no significant differences between control and stress groups with correlation coefficients. These findings are the first to show that chronic stress impairs both response inhibition and working memory, two behaviors that have never been directly compared within the same animals after chronic stress, using FMI, an appetitive task, and RAWM, a nonappetitive task.

Original languageEnglish (US)
Pages (from-to)605-619
Number of pages15
JournalBehavioral Neuroscience
Volume126
Issue number5
DOIs
StatePublished - Oct 2012

Keywords

  • Chronic stress
  • Fixed minimum interval
  • Impulsivity
  • Prefrontal cortex
  • Radial arm water maze
  • Rat
  • Reference memory
  • Response inhibition
  • Spatial working memory

ASJC Scopus subject areas

  • Behavioral Neuroscience

Fingerprint

Dive into the research topics of 'Chronic stress impairs prefrontal cortex-dependent response inhibition and spatial working memory'. Together they form a unique fingerprint.

Cite this