Rate of a Maintained Operant 1 Running Head: WITHIN-SESSION PATTERNS OF RESPONDING Rate of a Maintained Operant as a Function of Temporal Position Within a Session

The Abstract begins a new page. It should be short, but informative. It is used in the Psychological Abstracts, so it should be self-contained. The Abstract covers what the original questions were, what the answer was, and the conclusion drawn. Summarize the general procedure and the major findings in no more than 100-150 words. Avoid uninformative sentences such as "An explanation of the data was discussed. " Do not use abbreviations in this section. In summary, this section should contain statements of the problem, method, results and conclusions. Rate of a Maintained Operant 3 McSweeney and her colleagues (e.g., McSweeney, Hatfield, & Allen, 1990) have demonstrated reliable, large magnitude rate changes in maintained operants within daily sessions under a wide variety of reinforcement schedules. The present paper examined the role of schedule of reinforcement, reinforcement rate, and total amount of food access in determining those within-session rate changes. If median rates across birds were considered, then all procedures resulted in a brief period of an increasing rate, followed by a modest rate loss across the major portion of the session. However, not all individuals exhibited that pattern. When the amount of food access per session was limited by lower reinforcement rates, shorter sessions, or shorter reinforcement durations, then the magnitude of the within-session rate change was reduced from that occurring without those constraints. Additionally, under the conditions that produced strong within-session rate changes, the magnitude of the within-session rate loss was correlated with the bird’s body weight. These effects are consistent with what is typically labeled satiation. Rate of a Maintained Operant