There are many functions that occur in our body while we sleep, a recent study has looked at one that acts to wash out the brain while we sleep! Researchers have known for a while that neural activity occurs in waves in the brain while we sleep but before this recent study, no thought was given to what occurs to the cerebrospinal fluid during this time.
Research conducted by the Boston University published in Science for their October 31, 2019 issue looked at specifically what happened with this cerebrospinal fluid during sleep. Researchers enlisted a total of 13 subjects for this study whose age range was between 23 and 33 who were required to fall asleep while laying inside an MRI machine. Not ideal circumstances due to the immense noise that MRIs produced while operating but it was done.
Researchers found that during sleep, blood will rush out of the brain and be replaced with a flow of cerebrospinal fluid flowing into the brain and that these flows are tied closely to brain wave activity during sleep.
Researchers suggest that this flow of cerebrospinal fluid works to help flush out toxic, memory impairing proteins from the brain. Furthermore, as people age, their brains generate fewer slow waves during sleep which could lead to the reduction of these toxins being flushed out. Overall, the reduced pulsing of the cerebrospinal fluid could be a cause for the building up of these memory impairing proteins and cause memory loss in the aging population.
Moving forward to future studies, researchers would like to enlist an older population to see the effects on memory in regards to these pulses of cerebrospinal fluid to see if their hypothesis is correct. Furthermore, they wish to investigate how brain waves, blood slow, and cerebrospinal fluid all coordinate so well with each other. In a sense, we are being brain washed every night!
Source: http://www.bu.edu/articles/2019/cerebrospinal-fluid-washing-in-brain-during-sleep/
