An eight-alternative concurrent schedule: foraging in a radial maze

Area of Science:

• Behavioral neuroscience
• Animal behavior

Background:

• The generalized matching law describes choice behavior.
• Understanding sensitivity to reinforcement frequency is crucial for behavioral analysis.

Purpose of the Study:

• To investigate how different measures of foraging behavior (nose pokes, time in arm, arm entries) are sensitive to reinforcement frequency.
• To examine the effects of fixed-interval and random-interval schedules on this sensitivity.
• To assess the impact of a changeover delay on behavioral sensitivity.

Main Methods:

• Rats were trained in an eight-arm radial maze using fixed-interval or random-interval schedules of reinforcement.
• Behavioral data (nose pokes, time in arm, arm entries) were collected and analyzed using the generalized matching law.
• A changeover delay was introduced in a second experiment.

Main Results:

• Behavioral sensitivity to reinforcement frequency varied across measures: nose pokes > time in arm > arm entries.
• These sensitivity differences were consistent across both fixed-interval and random-interval schedules.
• A changeover delay reduced the sensitivity of nose pokes, diminishing the differences between measures.

Conclusions:

• Different components of foraging behavior exhibit distinct sensitivities to reinforcement frequency.
• The findings support the utility of the generalized matching law in describing animal foraging.
• Changeover delays can modulate behavioral sensitivity to reinforcement schedules.