The Yerkes-Dodson Law describes the empirical relationship between physiological arousal and task performance, named after a 1908 study by Robert Yerkes and John Dodson. Performance increases with arousal up to an optimal point, beyond which further arousal causes deterioration. The optimal arousal level varies with task complexity: simple tasks benefit from higher arousal, while complex tasks requiring working memory and executive function perform best at lower arousal levels. This principle has implications for cognitive testing conditions.
Neural Basis of the Inverted-U Curve
One account explains the inverted-U relationship through catecholamines in the prefrontal cortex: at moderate levels, norepinephrine and dopamine support the prefrontal networks underlying working memory. A review notes that even quite mild acute uncontrollable stress can rapidly impair prefrontal cognitive abilities.
Task Complexity and Optimal Arousal
A further aspect of the law is that optimal arousal shifts with task demands. Simple reaction time tasks benefit from relatively high arousal. However, complex tasks requiring information integration, such as working memory or decision-making paradigms, suffer under high arousal; one explanation points to attentional narrowing.
Arousal and Cognitive Test Results
If your test scores show high variability across sessions, inconsistent arousal states may be the cause.