Species differences in temporal control of behavior II: human performance.

Area of Science:

• Behavioral psychology
• Operant conditioning
• Animal behavior

Background:

• The study investigates human operant behavior under complex schedules of reinforcement.
• Differential-reinforcement-of-low-rate (DRL) schedules and fixed-interval (FI) schedules are common paradigms in behavioral research.
• Understanding human performance under these schedules can inform comparative analyses with other species.

Purpose of the Study:

• To examine human response patterns under a DRL schedule concurrent with two distinct fixed-interval (FI) schedules.
• To compare human performance to established findings in other species under FI schedules.
• To assess the sensitivity of human behavior to different contingency structures.

Main Methods:

• Human subjects responded on two panels: Panel A (DRL with limited hold) and Panel B (concurrent FI).
• Condition 1: Panel B responses produced a stimulus indicating reinforcement availability on Panel A.
• Condition 2: Panel B responses briefly illuminated a digital clock, effectively creating an FI schedule.

Main Results:

• Both conditions showed efficient Panel A performance, with responses occurring primarily when reinforcement was available.
• Condition 1 (DRL + stimulus signal) yielded a "break-and-run" pattern on Panel B, with linear increases in postreinforcement pause.
• Condition 2 (DRL + clock) produced a scalloped pattern on Panel B, sensitive to schedule parameters and resembling other species' FI performance.

Conclusions:

• Human performance under a DRL schedule is significantly influenced by the nature of the concurrent schedule.
• The presence of a temporal cue (digital clock) in Condition 2 increased sensitivity to the FI schedule, aligning with other species.
• These findings highlight the importance of stimulus control in shaping complex operant behavior in humans.