Date of Award


Degree Name

Doctor of Philosophy



First Advisor

Dr. Arthur Snapper

Second Advisor

Dr. Jack Michael

Third Advisor

Dr. Alan Poling


Previous concurrent operant research avoided concurrent superstition by techniques that ruled out the possibility of studying simultaneously reinforceable concurrent operants. So a procedure is needed that allows the study of simultaneously reinforceable concurrent operants while still avoiding concurrent superstition. One such procedure involves the use of a separate source of reinforcement for each operant rather than a single source for all operants. Assessment of the effectiveness of such a multi-source procedure relative to the effectiveness of the usual single-source procedure is the purpose of the present study.

Seven experimentally naive college students each participated in two to four 30 to 40 minute sessions, with minimal instructions being given. They responded on two telegraph keys, one for the left hand and one for the right hand. Points, accruing on counters, and flashing lights, served as reinforcers (the points were exchangeable for money). Under the single-source condition, all earned points appeared on the center counter. Under the two-source condition, earned points appeared on the counter whose physical location was associated with the point earning key.

All subjects received a training session first, where only one hand responded at a time, alternating hands for six to eight short components. One of the three remaining sessions was a within-subject, within-session comparison. The remaining two sessions were a within-subject, between session comparison. The comparison was always between the single and dual reinforcer-source conditions across component pairs involving CRF and EXT schedules.

Results from both between and within-session comparisons indicated that the dual-source condition was more effective in generating independence of schedule effects than the single source condition was.

The lack of subject sensitivity to the contingencies under the single-source condition is typical of the type of results that have deterred studies of simultaneously reinforceable concurrent operants in the past. The success of the two-source condition in showing subject sensitivity to the contingencies should encourage greater efforts in this area in the future, especially in regard to the experimental study of more complex human behaviors in the laboratory.

Access Setting

Dissertation-Campus Only