Preference for 50% reinforcement over 75% reinforcement by pigeons

Area of Science:

• Behavioral science
• Animal behavior
• Decision-making

Background:

• Pigeons exhibit complex choice behaviors when faced with different reinforcement schedules.
• Understanding these choices can shed light on the underlying mechanisms of decision-making under uncertainty.

Purpose of the Study:

• To investigate pigeon preferences between initial-link alternatives offering different reinforcement densities.
• To explore the potential role of contrast effects in explaining seemingly maladaptive choices.

Main Methods:

• Pigeons were presented with two initial-link options: one leading to a terminal stimulus with 50% reinforcement (100% or 0%), and another leading to 100% reinforcement.
• Reinforcement densities were systematically varied across two experiments.

Main Results:

• Experiment 1 showed a modest preference for 100% reinforcement over 50%.
• Experiment 2, with a 75% reinforcement alternative, revealed a significant preference for the 50% reinforcement option.
• Positive contrast effects may explain the preference for the 50% option when contrasted with a 100% outcome.

Conclusions:

• Pigeons can display paradoxical preferences for lower reinforcement schedules under specific conditions.
• These findings suggest that contrast effects play a crucial role in choice behavior.
• The observed behavior may serve as an animal model for human appetitive risk-taking, including gambling.