There is a Reason You Get Tired After School or Work – The Science Behind Mental Fog
Researchers found that when a brain performs intense cognitive work there is a byproduct build up in the prefrontal cortex that causes fatigue.
Researchers in France have found that when a brain performs intense cognitive work, typically for a few hours or longer, “potentially toxic byproducts” build up in the prefrontal cortex. That causes cognitive fatigue. So is thinking hard POISONING your brain? Not really but sort of, and this build-up can influence how people make decisions Steering you towards low-energy actions that may deliver rewards with no effort or waiting. In other words, when the brain gets tired, it doesn’t just use fatigue to push us to switch to a more gratifying activity. It can be a signal to slow down “to preserve the integrity of brain functioning.” The study didn’t provide a “hack” for bypassing this mental limitation other than the usual stuff like getting good rest and sleep.