The rat prelimbic cortex mediates inhibitory response control but not the consolidation of instrumental learning.
The potential role of the prelimbic cortex of the rat in the acquisition of instrumental responding is currently uncertain. In addition, modeling the acquisition of Pavlovian and spatial conditioning tasks has suggested that the process of acquisition can, for certain forms of learning, be step like and consequently misrepresented in averaged group curves. Here, the authors report an experiment investigating the potential involvement of the prelimbic cortex in instrumental acquisition, in which the authors used the control data to model individual acquisition curves mathematically. The authors show that instrumental acquisition under fixed interval schedules was a gradual process extending over 4 instrumental sessions that is well represented in averaged group curves. Postsession infusion of a protein synthesis inhibitor into the prelimbic cortex did not affect any measure of acquisition, showing that during acquisition the prelimbic cortex does not mediate postsession consolidation of instrumental learning. However, inactivation of the prelimbic cortex increased responding, suggesting that the prelimbic cortex mediates a form of inhibitory response control.
Jonkman
Sietse
S
Behavioural and Clinical Neuroscience Institute and Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, United Kingdom. sj306@cam.ac.uk
Mar
Adam C
AC
Dickinson
Anthony
A
Robbins
Trevor W
TW
Everitt
Barry J
BJ
D000704:Analysis of Variance; D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D001418:Baclofen / Q000494:pharmacology; D002404:Catheterization; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology* / Q000503:physiopathology; D003216:Conditioning, Operant / Q000187:drug effects / Q000502:physiology*; D018755:GABA Agonists / Q000494:pharmacology; D058785:GABA-A Receptor Agonists; D058786:GABA-B Receptor Agonists; D007175:Impulsive Behavior / Q000139:chemically induced / Q000503:physiopathology*; D007858:Learning / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D008845:Microinjections; D008960:Models, Psychological; D009118:Muscimol / Q000494:pharmacology; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D051381:Rats; D013997:Time Factors
D018755:GABA Agonists; D058785:GABA-A Receptor Agonists; D058786:GABA-B Receptor Agonists; D011500:Protein Synthesis Inhibitors; D009118:Muscimol; D000841:Anisomycin; D001418:Baclofen