Fiona D Zeeb1,2, P J J Baarendse3, L J M J Vanderschuren3,4, Catharine A Winstanley5. 1. Department of Psychology, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada. fiona.zeeb@camh.ca. 2. Centre for Addiction and Mental Health, Section of Biopsychology, Campbell Family Mental Health Research Institute, Toronto, ON, Canada. fiona.zeeb@camh.ca. 3. Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands. 4. Department of Animals in Science and Society, Division of Behavioural Neuroscience, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands. 5. Department of Psychology, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada. cwinstanley@psych.ubc.ca.
Abstract
RATIONALE: Studies employing the Iowa Gambling Task (IGT) demonstrated that areas of the frontal cortex, including the ventromedial prefrontal cortex, orbitofrontal cortex (OFC), dorsolateral prefrontal cortex, and anterior cingulate cortex (ACC), are involved in the decision-making process. However, the precise role of these regions in maintaining optimal choice is not clear. OBJECTIVES: We used the rat gambling task (rGT), a rodent analogue of the IGT, to determine whether inactivation of or altered dopamine signalling within discrete cortical sub-regions disrupts decision-making. METHODS: Following training on the rGT, animals were implanted with guide cannulae aimed at the prelimbic (PrL) or infralimbic (IL) cortices, the OFC, or the ACC. Prior to testing, rats received an infusion of saline or a combination of baclofen and muscimol (0.125 μg of each/side) to inactivate the region and an infusion of a dopamine D2 receptor antagonist (0, 0.1, 0.3, and 1.0 μg/side). RESULTS: Rats tended to increase their choice of a disadvantageous option and decrease their choice of the optimal option following inactivation of either the IL or PrL cortex. In contrast, OFC or ACC inactivation did not affect decision-making. Infusion of a dopamine D2 receptor antagonist into any sub-region did not alter choice preference. CONCLUSIONS: Online activity of the IL or PrL cortex is important for maintaining an optimal decision-making strategy, but optimal performance on the rGT does not require frontal cortex dopamine D2 receptor activation. Additionally, these results demonstrate that the roles of different cortical regions in cost-benefit decision-making may be dissociated using the rGT.
RATIONALE: Studies employing the Iowa Gambling Task (IGT) demonstrated that areas of the frontal cortex, including the ventromedial prefrontal cortex, orbitofrontal cortex (OFC), dorsolateral prefrontal cortex, and anterior cingulate cortex (ACC), are involved in the decision-making process. However, the precise role of these regions in maintaining optimal choice is not clear. OBJECTIVES: We used the rat gambling task (rGT), a rodent analogue of the IGT, to determine whether inactivation of or altered dopamine signalling within discrete cortical sub-regions disrupts decision-making. METHODS: Following training on the rGT, animals were implanted with guide cannulae aimed at the prelimbic (PrL) or infralimbic (IL) cortices, the OFC, or the ACC. Prior to testing, rats received an infusion of saline or a combination of baclofen and muscimol (0.125 μg of each/side) to inactivate the region and an infusion of a dopamine D2 receptor antagonist (0, 0.1, 0.3, and 1.0 μg/side). RESULTS:Rats tended to increase their choice of a disadvantageous option and decrease their choice of the optimal option following inactivation of either the IL or PrL cortex. In contrast, OFC or ACC inactivation did not affect decision-making. Infusion of a dopamine D2 receptor antagonist into any sub-region did not alter choice preference. CONCLUSIONS: Online activity of the IL or PrL cortex is important for maintaining an optimal decision-making strategy, but optimal performance on the rGT does not require frontal cortex dopamine D2 receptor activation. Additionally, these results demonstrate that the roles of different cortical regions in cost-benefit decision-making may be dissociated using the rGT.
Authors: Surya Pandey; Preeti S Badve; Genevieve R Curtis; Sarah F Leibowitz; Jessica R Barson Journal: Addict Biol Date: 2017-09-06 Impact factor: 4.280
Authors: Justin R Yates; Nicholas A Prior; Marissa R Chitwood; Haley A Day; Jonah R Heidel; Sarah E Hopkins; Brittany T Muncie; Tatiana A Paradella-Bradley; Alexandra P Sestito; Ashley N Vecchiola; Emily E Wells Journal: Exp Clin Psychopharmacol Date: 2018-07-23 Impact factor: 3.157