Introducing the brain: rebooting after deep anesthesia (Introduction)

by David Turell , Saturday, March 12, 2022, 02:11 (776 days ago) @ David Turell

FMRI and other methods used:

https://www.sciencealert.com/here-s-how-the-human-brain-reboots-itself-after-the-deep-s...

"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.

"'Although initially surprising, it makes sense in evolutionary terms that higher cognition needs to recover early," said anesthesiologist Max Kelz, from the University of Pennsylvania.

"'If, for example, someone was waking up to a threat, structures like the prefrontal cortex would be important for categorizing the situation and generating an action plan."

"A variety of methods were used to measure what was happening in the brain, including electroencephalography (EEG) scans and cognitive tests before and after going under. These tests measured reaction speed, memory recall, and other skills.

"Analyzing the EEG readings, the researchers noted that the frontal regions of the brain – where functions including problem-solving, memory, and motor control are located – became particularly active as the brain began to recover.

"A comparison with the control group showed that it took about three hours for those who had been anesthetized to recover fully.

***

"Despite their widespread use, we don't really understand how anesthetics work in precise detail, even if we have figured out how to use them safely. There are plenty of ideas about how the brain deals with these drugs, but no concrete evidence as yet.

"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."

Comment: just of interest. It certainly doesn't tell us where consciousness comes from.