Evidence for capacity sharing when stopping.

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Multitasking performance declines when central processing demands overlap.
• Stopping responses have been considered an exception, with models assuming independence from 'go' processes.
• Previous research often simplified the stop task while varying 'go' task difficulty.

Purpose of the Study:

• To investigate capacity sharing between stopping and going responses.
• To examine how stop task difficulty influences this interaction.
• To challenge the independence assumption in selective stop tasks.

Main Methods:

• Four experiments using a selective stop-change task.
• Manipulation of stop task difficulty while keeping the 'go' task difficulty constant.
• Comparison of consistent-mapping versus varied-mapping conditions to modulate rule-based system demands.

Main Results:

• Strong dependence observed between stopping and going processes.
• This dependence was particularly pronounced in the varied-mapping condition.
• Performance varied significantly across conditions, subjects, and groups.

Conclusions:

• The decision to stop or not in selective stop tasks shares processing capacity with the 'go' task.
• This finding challenges the long-held independence assumption.
• Implications for understanding dual-task performance and the stop-signal paradigm are discussed.