title: Dopamine modulates effort-based decision making in rats.
abstract: Previous research has implicated dopamine as a modulating factor in choice behavior based on effort. The purpose of the present study was to determine the individual contribution of different dopamine receptors to effort-based decision making in rats. Rats were trained in a T-maze to choose a large-reward arm that contained 8 pellets of food over a small-reward arm that contained 2 pellets of food. The rats then were trained to climb progressively higher barriers to obtain the food from the large-reward arm. Using a discounting procedure on each test day, it was found that rats were more likely to choose the small-reward arm after treatment with the D1 antagonist, SCH-23390, or the D2 antagonist, haloperidol. The dopamine agonist, D-amphetamine, biased the rats toward choosing the large-reward arm and blunted the effects of SCH-23390 or haloperidol. Treatment with the D3 receptor antagonist, U99194, or the D3 receptor agonist, 7-OH-DPAT, did not alter choice behavior. These data indicate that D1 and D2 receptors are required for decisions based on effort.
authors.affiliation: Department of Psychology, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY 41076, USA. bardgettm@nku.edu
authors.forename: Mark E
authors.initials: ME
authors.lastname: Bardgett
authors.forename: Melissa
authors.initials: M
authors.lastname: Depenbrock
authors.forename: Nathan
authors.initials: N
authors.lastname: Downs
authors.forename: Megan
authors.initials: M
authors.lastname: Points
authors.forename: Leonard
authors.initials: L
authors.lastname: Green