The matching law has been a prevalent theory in behavior analysis for the past thirty years. This theory states that responding changes as a monotonic function of reinforcement. However, several studies have found bitonic functions. One reason for this discrepancy may be due to circadian entrainment. There is evidence that rats are sensitive to circadian rhythms and that rats are capable of entraining to two feeding times per day. Also, it may be that the biological makeup of rats consists of two separate rhythm oscillators. One involves food and the other involves light. The present experiments attempted to discover what role circadian rhythms have in shaping the VI response function. Rats were exposed to a series of conditions involving different session times as well as different reinforcement schedules. Although significant differences were found between VI schedule and response rate, there were no significant effects of circadian entrainment on the VI response function. This may be due to the sensitivity of circadian rhythms in animals. Future research is needed to determine what role entrainment does play in behavior analysis.
Lionello '95, Karen M., "The Effects of Circadian Entrainment on Operant Conditioning" (1995). Honors Projects. Paper 73.