You might have heard of people using "white noise" machines. But it turns out there's a whole rainbow of noises out there.
Scientists at Northwestern University are looking at something called "pink noise" -- to see if it can help you get a better night's sleep and also improve your memory.
One of those researchers, associate professor of neurology Doctor Malkani joined ABC7 to talk about pink noise as well as the relationship between sleep and memory.
White noise is similar to static on a radio or TV. Pink noise turns down the volume on those higher frequencies, so it sounds lower in pitch and more like the natural sound of rain or the ocean.