Divided control by past behavior, present stimuli, and future outcome value in a concurrent-chains procedure.

Area of Science:

• Behavioral psychology
• Animal cognition
• Reinforcement learning

Background:

• Stimulus control can be divided among multiple signals.
• Outcome value influences the strength of stimulus control.
• Understanding divided stimulus control is key to behavioral analysis.

Purpose of the Study:

• Investigate how divided stimulus control interacts with outcome value.
• Examine the relative influence of past behavior, past signals, and present signals.
• Determine the role of subjective outcome preference in stimulus control.

Main Methods:

• Used a concurrent-chains procedure with pigeons.
• Manipulated outcome magnitude and delay (smaller-sooner vs. larger-later reinforcers).
• Assessed stimulus control by past behavior, past signals, and present signals.

Main Results:

• Past behavior strongly controlled terminal-link responding, overshadowing past signals.
• Present signals exerted some control, especially later in the terminal links.
• Stimuli signaling preferred outcomes (smaller-sooner) had stronger control.

Conclusions:

• Subjective outcome value is crucial for understanding stimulus control.
• Egocentric stimuli (past behavior) can maintain enduring control.
• Divided stimulus control is influenced by the temporal proximity and subjective value of signals and outcomes.