Five subjects (11, 14, 15, 17, and 20) showed mainly short PRPs on the conjunctive with an abrupt shift to extended PRPs on the FI; this shift occurred toward the end of the session for S14 and S17.
Eight subjects (all but S23 and S25) showed high response rates and short PRP durations on FI 10-s followed by a decrease in response rates and an increase in PRPs during exposure to the conjunctive FT 10-s FR 1 schedule.
Subject 25 emitted a low response rate and extended PRPs across FI and conjunctive schedules.
For Subjects 37 and 38 response rates were low across all trials on the conjunctive schedule (the first 1-s delay occurred on the first trial for S38, and on the second trial for S37).
A 1-s delay did not occur for either of these subjects on the conjunctive schedule.
The conjunctive schedule, however, produced consistent low-rate performances for most subjects, even when they were given ratio-based verbal instructions.
Consider the general change in performance in the FI to conjunctive condition.
It should be noted, however, that variation in the frequency of response-reinforcer contiguity was not the only change in response- reinforcer relations that could occur across the FI and conjunctive schedules.
However, when subjects were exposed to the conjunctive first, 17 out of 20 subjects tended to produce low rates, and these 17 subjects also produced the low-rate performance on the FI schedule.
A normal recycling conjunctive FT FR 1 schedule and a modified recycling conjunctive FT FR 1 schedule were used during Experiment 2.