Effects of Stroop task duration on subsequent cognitive and physical performance.

Area of Science:

• Cognitive Psychology
• Neuroscience
• Exercise Physiology

Background:

• The strength model of self-control posits that ego-depleting tasks impair subsequent self-control performance.
• Evidence suggests longer cognitive tasks might improve, not impair, subsequent performance, challenging the strength model.

Purpose of the Study:

• Investigate the impact of cognitive task duration on physical endurance.
• Assess effects on concurrent cognitive task performance.
• Examine performance on a subsequent novel cognitive task.

Main Methods:

• Experimental design with Stroop task type (incongruent/congruent) and duration (5, 10, 20 min) as factors.
• 180 participants completed Stroop tasks, an isometric handgrip endurance task, and a novel Stroop task.
• Measured endurance, cognitive accuracy, and reaction times.

Main Results:

• Isometric handgrip endurance was impaired by incongruent Stroop tasks at 10 min, but not 5 or 20 min.
• Concurrent Stroop task accuracy decreased and speed slowed after incongruent tasks.
• Reaction times improved with longer cognitive task durations.
• Novel Stroop task accuracy was higher after incongruent tasks.

Conclusions:

• Ego depletion effects are moderated by cognitive task duration.
• The expected value of control model provides a better explanation than the strength model for these findings.