Failure to produce response variability with reinforcement.

Area of Science:

• Behavioral psychology
• Animal cognition

Background:

• Behavioral research often involves training animals to perform specific tasks.
• Understanding response variability is crucial for analyzing learning processes.

Purpose of the Study:

• To investigate pigeons' ability to generate variable response sequences.
• To determine if pigeons can learn to avoid repeating response patterns when reinforcement is contingent on novelty.

Main Methods:

• Two experiments were conducted with pigeons (Columba livia).
• Experiment 1: Naive pigeons were trained on a task requiring four pecks on two keys, with reinforcement for novel sequences.
• Experiment 2: Pigeons previously trained on alternating sequences were exposed to the novelty-based reinforcement task.

Main Results:

• Pigeons failed to produce a wide range of response sequences in both experiments.
• Stereotyped sequences emerged despite reinforcement being contingent on response variability.
• Reinforcer delivery was below 50% of the maximum possible, indicating task difficulty or limitations in sequence generation.

Conclusions:

• The hedonic properties of reinforcers may promote response stereotypy, even when it hinders obtaining rewards.
• Pigeons' capacity for producing variable response sequences under these conditions is limited.
• Reinforcement may have both informative and hedonic roles, with the latter potentially overriding the former in promoting repetition.