Summation of responding maintained by fixed-interval schedules.

Area of Science:

• Behavioral psychology
• Operant conditioning

Background:

• Fixed-interval schedules maintain responding where rates vary across the interval.
• Stimuli can acquire control over behavior under interval schedules.

Purpose of the Study:

• To compare response rates during single stimuli versus compound stimuli.
• To determine if response tendencies during compound stimuli are additive.

Main Methods:

• Behavioral responding was measured under fixed-interval schedules.
• Responding to light and tone stimuli, presented alone and compounded, was analyzed across interval segments.

Main Results:

• More responses occurred during compound stimuli than single stimuli across all interval segments.
• Response rate increases across the interval were similar for compound and single stimuli.
• The total responses to combined stimuli approximated the sum of responses to individual stimuli.

Conclusions:

• Compound stimuli enhance responding compared to individual stimuli under fixed-interval schedules.
• Response control by compound stimuli appears to be summative or additive.