What is the definition of mental fatigue? How to measure it?

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Definition of Mental Fatigue

Mental fatigue is a psychobiological state of tiredness caused by prolonged periods of performing demanding, cognitive-load-inducing activities, resulting in reduced efficiency in cognitive performance. It arises when the brain is overloaded with information or tasks, making it challenging to process everything effectively. Mental fatigue can impair the ability to function normally, causing irritation and disrupting sleep.

Measuring Mental Fatigue

Mental fatigue can be measured using self-report questionnaires that assess symptoms such as feeling depressed, anxious, apathetic, or irritable. Behavioral tasks that evaluate performance on cognitively demanding activities over time can also provide insights into mental fatigue levels. Monitoring physical signs like headaches, sleep disturbances, and frequent illness can further help detect mental exhaustion.