People feel exhausted after intense mental activity because all of that hard thinking triggers a buildup of toxic chemicals in the brain, according to researchers at Pitié-Salpêtrière University in Paris.
What to know:
When you spend prolong periods engaging in mentally taxing activities, potentially a toxic by-product called glutamate builds up in the prefrontal cortex of the brain.
The prefrontal cortex helps control decisions, and choices can be altered when glutamate begins interfering with thought processes, shifting decisions toward easy actions that require no effort as mental fatigue sets in.
The prefrontal cortex seems especially susceptible to glutamate accumulation after a mentally tough workday and mental fatigue sets in, prohibiting one from staying continuously focused on a task and diverting one's attention to something less taxing.
Experiencing difficulty with cognitive control signals that the brain has a need to get rid of potentially toxic substances that arise from neural activity and that it is working to preserve the integrity of its functionality.
Evidence suggests that glutamate is eliminated from synapses during sleep, so you should avoid making important decisions when you tired.
This is a summary of the article, "A Neuro-Metabolic Account of Why Daylong Cognitive Work Alters the Control of Economic Decisions," published in Current Biology on August 11, 2022. The full article can be found on cell.com.
Cite this: There's Good Reason Why Hard Thinking Makes You Tired - Medscape - Sep 07, 2022.