Dependency Effects Of Pemoline And Ritalin On Responding Rate Under A Fixed Interval Schedule Of Reinforcement

Abstract

The behavioral effects of 2.0-16.0 mg/kg of methylphenidate (Ritalin) and phenylisohydointoin (Pemoline) administered orally on key-pecking reinforced under a fixed-interval (FI) 120-sec schedule for food in homing pigeons were studied. The behavioral effects of both methylphenidate and pheylisohydointoin were dose dependent: Response rates increased at dosages of 4.0, 8.0, and 16 mg/kg. The response-rate changes during the FI are in accord with the rate-dependency hypothesis. Ritalin increased responding at 16 mg/kg differently than 8 mg/kg which was also different than 4 mg/kg. Pemoline on the otherhand increased responding over baseline, yet 4, 8, and 16 mg/kg all had the same effect. Pemoline and Ritalin at 2 mg/kg did not affect responding.