Why concentration makes your brain feel knackered

[Retro]

I've noticed it especially when sitting exams where I have to concentrate really hard for a couple of hours. My head literally feels warmer and I feel worn out, taking time to recover. Now it looks like this effect isn't just an illusion, but can actually be objectively measured. This isn't a definitive study on this effect as it's early research, but it does show that heavy concentration really does tire one out.

Also, doing something simple, but repetitive and exacting leads to the same kind of intense concentration and knackered feeling.

The brain could suffer from something similar to the painful buildup of lactate in muscles during physical exercise. This could be why hard mental yards – and resisting the temptation to give up throughout the day – feel equally taxing.

Prolonged mental activity leads to the accumulation of a potentially toxic neurotransmitter in the prefrontal cortex, according to a study published in Current Biology. The researchers suggest the brain slows down its activity to manage the buildup, offering an explanation to why we feel tired.

Brain drain: scientists look at why mental exertion triggers exhaustion

Prolonged mental activity leads to buildup of potentially toxic neurotransmitter in brain, study finds

www.theguardian.com