Yerkes-Dodson Law: Zero stress leads to zero performance

The Yerkes-Dodson Law is the inverted U-shaped relationship between arousal levels and task performance, discovered in 1908 by psychologists Robert Yerkes and John Dodson.

The Inverted U-Curve

• Low Arousal — Boredom, lethargy, and lack of motivation. This occurs when repeating tasks that are too easy, leading to a state of apathy.
• Optimal Arousal — The point where focus and immersion are at their peak. Moderate tension enhances performance.
• High Arousal — Anxiety, freezing, and impaired judgment. Excessive pressure causes performance to collapse.

Differences Based on Task Difficulty

A key finding of the original study: Simple tasks can be performed well even at relatively high levels of arousal, whereas complex tasks show optimal performance at lower levels of arousal. This means that the more difficult the task, the more a calm state is required.

Implications for Stress Management

This law teaches us that “zero stress” is not the goal. The objective is to reduce distress (harmful stress) and maintain eustress (optimal stimulation). While burnout is the accumulation of distress, lethargy can be the result of a lack of stimulation.

Source: Yerkes RM, Dodson JD. “The relation of strength of stimulus to rapidity of habit-formation.” J Comp Neurol Psychol. 1908;18:459-482.

Related: Burnout Test · Holmes-Rahe Stress Test