Choice performance in several concurrent key-peck treadle-press reinforcement schedules

Area of Science:

• Behavioral psychology
• Animal behavior
• Operant conditioning

Background:

• Concurrent variable-interval schedules are used to study choice behavior in animals.
• Understanding how animals allocate responses between different options is crucial for behavioral science.
• Previous research has explored matching laws in animal behavior.

Purpose of the Study:

• To investigate how pigeons allocate their time and responses between two concurrent schedules of food reinforcement.
• To examine the relationship between the relative frequency of reinforcement and response allocation.
• To determine if key pecking has a unique advantage over treadle pressing in acquiring food reinforcement.

Main Methods:

• Five pigeons were exposed to concurrent variable-interval schedules.
• Two groups of pigeons were used: Key-Treadle (key pecking and treadle pressing) and Treadle-Treadle (two treadle pressing responses).
• The relative probability of reinforcement for each response alternative was systematically varied.

Main Results:

• Logarithms of relative time spent responding and relative response numbers showed a direct linear relationship with logarithms of relative reinforcement frequencies.
• No bias was observed for key pecking over treadle pressing.
• All subjects demonstrated undermatching, allocating responses and time in a manner less sensitive to reinforcement differences than predicted by the matching law.

Conclusions:

• Pigeon's response allocation in concurrent schedules is predictable based on reinforcement frequencies, following a linear logarithmic relationship.
• Key pecking does not possess an inherent advantage over treadle pressing for food reinforcement.
• Undermatching suggests a tendency towards indifference in response allocation when reinforcement ratios are manipulated.