Mental fatigue is the result of brain over-activity. It can happen when you expend too much mental effort on a project or task. You may pride yourself on your laser-focusing ability, spending long hours on a task, day in and day out. But every strength, taken to the extreme, becomes a liability.

What happens to your brain when you are fatigued?

Finding it hard to concentrate? Sleep deprivation disrupts the way brain cells communicate with each other, which may explain why a bad night's sleep can cause memory lapses and poor concentration.

What part of the brain causes fatigue?

The basal ganglia are at the base of the brain and are associated with a variety of functions, including motor activity and motivation. Diseases affecting basal ganglia are often associated with fatigue.