Varying reinforcer duration produces behavioral interactions during multiple schedules

Area of Science:

• Behavioral psychology
• Animal behavior
• Operant conditioning

Background:

• Behavioral interactions in multiple schedules are not fully understood.
• Habituation to reinforcers may play a role in these interactions.
• Previous research has not fully explored the impact of reinforcer changes on habituation and subsequent behavior.

Purpose of the Study:

• To test the hypothesis that changes in habituation to reinforcers contribute to behavioral interactions.
• To investigate whether altering reinforcer characteristics disrupts habituation and induces behavioral interactions.
• To examine the role of reinforcement rate and variability in these phenomena.

Main Methods:

• Pigeons and rats were trained on multiple variable interval-variable interval schedules.
• Variability was introduced into the duration of reinforcers in one component of the schedule.
• Response rates in both components were monitored under conditions of fixed and variable reinforcer durations.

Main Results:

• Introducing variability in reinforcer duration increased response rates in both schedule components when reinforcement rates were high, but not low.
• The magnitude of increased response rates in the constant-component schedule grew over the session.
• Within-session decreases in responding were less pronounced when the other component offered variable-duration reinforcers compared to fixed-duration reinforcers.

Conclusions:

• The findings support the idea that changes in reinforcer habituation contribute to behavioral interactions.
• These results offer an explanation for why behavioral interactions occur in some subjects but not others.
• The study challenges the assumption that induction and behavioral contrast are always mediated by distinct theoretical mechanisms.