Appetitive Instrumental Learning Task
Objective: To examine whether coincident activation of NMDA and dopamine D1 receptors within the nucleus accumbens core is required for acquisition of appetitive instrumental learning (lever pressing for food) in rats
Gather these items before starting the experiment. Check off items as you prepare.
Equipment1
Not specified • Not specified • Not specified • Not specified
Materials2
Software1
Not specified • Not specified
As an Amazon Associate, we earn from qualifying purchases. Product links help support this free resource.
Protocol Steps
Baseline assessment of feeding and motor activity
Establish baseline indices of feeding and motor activity prior to instrumental learning task
Note: These measures will be used to assess specificity of drug effects on learning versus general behavioral effects
View evidence from paper
“Infusion of the combined low doses had no effect on indices of feeding and motor activity, suggesting a specific effect on learning”
Infusion of AP-5 alone into nucleus accumbens core
Infuse 5 nmol AP-5 (NMDA receptor antagonist) into the nucleus accumbens core to establish baseline effect on acquisition of instrumental learning
Note: This condition tests NMDA receptor blockade alone
View evidence from paper
“blockade of NMDA receptors in the core with the antagonist 2-amino-5-phosphonopentanoic acid (AP-5; 5 nmol) abolishes acquisition but not performance”
Infusion of SCH-23390 alone into nucleus accumbens core
Infuse 0.3 nmol SCH-23390 (D1 receptor antagonist) into the nucleus accumbens core to establish baseline effect on instrumental learning
Note: Low dose used; when infused separately, this dose had no effect on learning
View evidence from paper
“when infused separately, these low doses had no effect”
Co-infusion of low-dose AP-5 and SCH-23390 into nucleus accumbens core
Simultaneously infuse 0.5 nmol AP-5 and 0.3 nmol SCH-23390 into the nucleus accumbens core
Note: Combined low doses that individually have no effect; this is the critical experimental condition
View evidence from paper
“Co-infusion of low doses of the D1 receptor antagonist SCH-23390 (0.3 nmol) and AP-5 (0.5 nmol) into the accumbens core strongly impaired acquisition of instrumental learning”
Lever pressing task for food reinforcement
Conduct appetitive instrumental learning task where rats press levers to obtain food reward following each infusion condition
Note: Task measures acquisition and performance of instrumental learning
View evidence from paper
“acquisition of instrumental learning (lever pressing for food)”
Assessment of feeding and motor activity post-infusion
Measure indices of feeding and motor activity following each infusion condition to determine specificity of effects
Note: Used to confirm that combined infusion effects are specific to learning and not due to general behavioral impairment
View evidence from paper
“Infusion of the combined low doses had no effect on indices of feeding and motor activity, suggesting a specific effect on learning”