Anticipatory contrast and diet selection by pigeons

Area of Science:

• Behavioral neuroscience
• Animal behavior
• Operant conditioning

Background:

• Understanding reinforcement schedules is crucial for behavioral analysis.
• Contrast effects, where prior reinforcement influences subsequent behavior, are well-documented.
• The relationship between reinforcement rate and choice behavior requires further investigation.

Purpose of the Study:

• To investigate how future reinforcement rates impact pigeons' choice and response rates.
• To examine the contrast effect in a simulated diet selection task.
• To differentiate the mechanisms underlying changes in response rate versus choice behavior.

Main Methods:

• Three experiments utilized pigeons performing an operant diet selection task.
• Subsequent reinforcement rates (high or low) were manipulated using within-subjects and between-subjects designs.
• Response rates and choice behavior were measured under varying experimental conditions.

Main Results:

• Response rates exhibited contrast effects, with stronger effects observed in within-subjects designs (Experiment 3) compared to between-subjects designs (Experiment 2).
• A conditioning effect was noted in Experiment 2.
• Changes in choice behavior were consistently weak across experiments.

Conclusions:

• The findings indicate that the mechanisms driving contrast effects in response rate differ from those influencing choice behavior.
• Reinforcement rate significantly impacts response rate, but has a limited effect on choice in this paradigm.
• Results have implications for understanding foraging strategies and behavioral economics.