Differential reinforcement of low rates of responding (DRL) is an operant test that requires behavioral suppression: the withholding of a response for a period such as 72 seconds (‘DRL72s’).
DRL72s has predictive validity for antidepressant drugs. Administration of different classes of antidepressant (tricyclics, MAOIs, SSRIs) results in a decrease in response rate and an increase in reinforcement rate.
Non-antidepressant drugs have different profiles of effects, such as, psychostimulants, which increase lever-presses and decrease reinforcers earned.
Effects of Tricyclic Antidepressants in DRL72 in Rats
Imipramine and Desipramine increase reinforcement rates and decrease response rate.