Date of Award


Degree Type


Degree Name

Departmental Honors




The spontaneously hypertensive rat (SHR) is the outcome of selectively breeding its progenitor the Wistar Kyoto (WKY) for hypertension. In the present experiment, the context of reinforcement was manipulated to determine its effect on impulsivity across the SHR and WKY strains of rat. An additional block of delays was added onto the end of a standard delay discounting procedure to vary the context of reinforcement from one condition (0 sec.) to the next (60 sec.). Results indicate that both SHR and WKY subjects made fewer impulsive decisions when a shorter delay followed the longest delay in the task - although this effect was more pronounced in the SHR strain. This suggests that differences in contextual factors of reinforcement may affect impulsivity, but that the magnitude of this effect may depend on fundamental differences in genetics or other biological substrates.

Included in

Psychology Commons


Faculty Mentor

Amy L. Odum