Did you get a good night’s sleep? Did the extra hour in bed make you wake up feeling refreshed? If you answered “yes” to either of these questions, you have your amazing brain to thank.
Researchers at Boston University have gained a greater understanding as to what happens in the brain during sleep. As the brain’s activity slows down and your neurons stop firing, you gradually settle into sleep. It’s during this serene period that your brain starts its housekeeping. While you sleep, blood rapidly drains out of the brain, resulting in a loss of pressure, with cerebrospinal fluid (CSF) rushing in to restore balance.
With the aid of magnetic resonance imagery, the research team was able to see for the first time the rhythmic and pulsating waves of CSF in the brain. It is very similar to how a washing machine oscillates the water in the drum to do your laundry – effectively “brainwashing” you. The theory is that as the brain slows down, it requires fewer nutrients, and the body reduces blood supply to the brain, believed to be the precursor to the “brainwashing” process.
How exactly this fine-tuned waltz between the reduction in blood flow to the brain and the release of CSF to replace it happens remains a mystery. CSF has been previously associated with the removal of toxins from the brain, including beta-amyloid known to be linked to Alzheimer’s disease.
Disrupted sleep patterns affect 50 million to 70 million Americans of all ages and are a hallmark of numerous mental health and neurological disorders, including depression, anxiety, post-traumatic stress disorder, dementia and autism. Disrupted sleep increases the severity, duration and relapse rates for the majority of mental health disorders, suggesting that toxin buildup in the brain may be a contributing factor.
We know that as the brain ages, the intensity of CSF waves reduces and may explain the decline in cognitive function and memory. Fortunately, recent studies have shown that treatments that promote sleep – either with pharmacological or nonpharmacological approaches – may reduce and even prevent mental and neurological disorders by encouraging “brainwashing” to speed up the removal of toxin buildup.
Rita Hitching is a local researcher and teacher who writes on teen brain development. She aims to help teens understand themselves by using the latest neuroscience data to explain how the teen body and brain develop and publishes those explanations on her website, teenbrain.info.