Date of Award


Degree Name

Doctor of Philosophy



First Advisor

Dr. Alan D. Poling

Second Advisor

Dr. David Lyon

Third Advisor

Dr. Jack Michael

Fourth Advisor

Dr. C. Dennis Simpson


The purpose of the present study was twofold: To determine the effects of LSD (0.03 - 1.0 mg/kg), mescaline (0.3 - 5.6 mg/kg), and DMT (0.3 - 3.0 mg/kg) on the performance of pigeons under two variants on an FCN schedule and to determine whether these effects differed substantially as a result of experimental design (i.e., within subject or between-subjects). Under this schedule, food was delivered whenever subjects responded between eight and 12 times on one response key (work key), then responded once on a second key (reinforcement key). Under one version, (FCN-S^D), an external discriminative stimulus was correlated with the completion of the response requirement on the work key; no such stimulus change was programmed to occur under the other schedule (FCN).

Although small differences were apparent, within-subject and between-subjects comparisons yielded comparable results. In the absence of drug, accuracy (percent reinforced runs) was higher under the FCN-S^D schedule. LSD and DMT had little effect on accuracy under either the FCN or the FCN-S^D schedule. Mescaline, in contrast, reduced accuracy under both of these schedules.

Access Setting

Dissertation-Open Access

Included in

Psychology Commons