Mental strain fatigue is the weariness produced by sustained mental work — long hours of reading and notation, careful scribing or copying, focused calculation, or the patient deciphering of a difficult text. The body sits still while the mind labors, and the cost is real even though no muscle has moved. 5 fatigue per four hours of focused study.
Symptoms
Eye strain, mild headache behind the temples, stiff neck and shoulders from posture, slow blink, difficulty re-reading a line, fingers cramped from the quill, the urge to pace or lie down.
Progression
Past the weariness ceiling, the mind simply will not hold the work — sentences slip the moment they are read, calculations refuse to resolve, the pen wanders. Continued study at exhaustion produces errors that must be reworked when fresh.
Treatment
- Stop
- Walk for a quarter hour; look at distant objects
- Drink water; small food if it has been long since a meal
- Resume only when the mind is willing rather than driven
Recovery
Four hours of rest reduces weariness fatigue by 5; eight hours of sleep reduces it by 15.