A pink addition to your sleep can help wash out your brain

Think pink for better sleep and extra brain benefits.While research is mixed about the benefits of background noise during sleep, many have added apps and ambient sound machines to nighttime routines for reduced clamor and improved rest.And our brains could see a big benefit with sound machines — and one type of static noise in particular — helping give our noggins a good cleaning out.Throughout the day, our brains accumulate waste and toxins (like lactic acid and worn-out proteins) that can be harmful if left to build up.However, the brain’s glymphatic system uses waves of cerebrospinal fluid (CSF) to flush out waste, a process that conveniently happens during deep, non-REM sleep.Without this “clean-up,” waste and toxins can trigger inflammation, disrupt communication between brain cells and eventually lead to neuron damage.A recent study from MIT has found that tiny bursts of “pink noise” during sleep can increase the amplitude of slow electrical waves, which strengthens CSF waves.Like white noise, pink noise is a steady background noise, often similar to ambient noise.Pink noise, however, uses deeper sounds and lower frequencies to create a more even, flat sound, like steady rain or a distant waterfall.The team behind the study wanted to explore the relationship between brain waves and CSF flow, and determine if manipulating the brain waves could enhance cerebrospinal fluid flow.Earlier research has shown that auditory stimuli played at the peak of slow waves that occur during deep sleep can deepen CSF waves.“Similar to a child on a swing, if you push them when they’re at the right moment in their movement, you can make that swing go farther,” senior study author Laura Lewis said in a press release.“The challenge is: How do you find just the right time?”Testing 14 healthy participants, researchers delivered a 50-millisecond burst of pink noise at the slow wave peaks.While the burst of noise wasn’t loud enough to wake the parti...