You may well have spent hours wondering what your laptop is up to as it takes its time to boot up. Scientists have asked the same question of the human brain: How exactly does it restart after being anesthetized, in a coma, or in a deep sleep?

Using a group of 30 healthy adults who were anesthetized for three hours, and a group of 30 healthy adults who weren't as a control measure, a 2021 study reveals some insights into how the brain drags itself back into consciousness.

It turns out that the brain switches back on one section at a time, rather than all at once – and abstract problem-solving capabilities, as handled by the prefrontal cortex, are the functions that come back online the quickest. Other brain areas, including those managing reaction time and attention, take longer.

The recent findings can not only help with treatments and patient care – after major operations involving anesthesia, for example – but also in giving scientists a better understanding of the brain and how it responds to disruption.

"How the brain recovers from states of unconsciousness is important clinically but also gives us insight into the neural basis of consciousness itself," said anesthesiologist George Mashour, from the University of Michigan.

Read the full article at ScienceAlert.