Effects of desmopressin acetate (DDAVP) on the learning of a brightness discrimination.

Sixty male albino rats received DDAVP, a placebo, or control treatment and were tested on a brightness discrimination task. Three groups (DDAVP, placebo, and control) were tested in the morning and three groups were tested in the evening. The acquisition and reversal of the brightness discrimination, along with the retention of the reversal problem after a 5-day retention interval were analyzed. Inspection of forward and backward learning curves plotted for each task revealed facilitated acquisition along with an initial impairment of reversal learning in those animals treated with DDAVP. These results support a memorial interpretation of DDAVP's effects. This was short-term in duration, as no retention effects were obtained. It was also found that DDAVP's effects were not influenced by diurnal processes.