Date of Degree


Document Type


Degree Name





Bruce L. Brown

Subject Categories

Other Psychology | Psychology | Social and Behavioral Sciences


Incentive Motivation, Interval Timing


Pavlovian incentive motivation provides a theoretical framework on the basis of which experiments can be designed to examine the effects of motivational variables on timing behavior. The Pavlovian-Instrumental transfer (PIT) paradigm is a prototype for studying Pavlovian incentive motivation. The current study examined the effect of a Pavlovian appetitive conditioned stimulus (CS) on timing performance, based on the PIT paradigm. Nine pigeons were exposed to pairings of a 120-s conditioned stimulus (flashing or steady houselight) and unconditioned stimulus (food). The pigeons were then trained on the peak procedure (FI 30 s). In a subsequent testing phase, the effect of the CS on the performance during non-reinforced probe trials was assessed by embedding probe trials within the CS. The major effect of the CS on timing performance was to increase the time at which pigeons stopped responding on the embedded probe trials. One likely mechanism that could account for the finding of this experiment is that the motivational property of a CS changes the threshold that is applied to the decision mechanism in an information-processing clock model.