The behavioral theory of timing (Killeen & Fetterman, 1988) holds that animals use behavioral tasks, called adjunctive behaviors, to aid them in timing intervals. Several studies have supported this theory, however the majority of these studies have been correlational. The present study used an experimental approach to manipulate the presence of adjunctive behavior. Rats responded on two DRL limited-hold procedures in which subjects must wait a certain time interval before responding; early responses were not reinforced and reset the clock. In addition, the animal had a specific interval of time in which to make a response; late responses were not reinforced and also reset the clock. The opportunity for adjunctive behavior was manipulated with a chew block which was provided for half of the sessions. The results show that the presence of the chew block did not have an effect on timing ability. In fact very little chewing occurred, and when chewing did occur it interfered with timing ability. This violates the predictions of BeT that chewing would improve timing ability. However, the low rates of chewing show that perhaps this is not an appropriate test for BeT. In addition, it is possible that other adjunctive behaviors were occurring during the experimental sessions. Future studies should include more subjects, run more sessions, and examine all behavior during each session.
Skarvan '04, Jill, "Behavioral Theory of Timing Applied to a DRL-Limited Hold Procedure" (2004). Honors Projects. Paper 24.