New wearable devices target the brain to bring better sleep

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Subscribe to enjoy similar stories. The clock is ticking. You should have been asleep long ago.

But instead, you’re lying in bed wide awake, wondering if you’ll ever doze off. New gadgets that target the brain promise to speed up the onset of sleep, improve the length and quality of rest, and even transition travelers to a different time zone before their planes touch down. This isn’t as far out as it sounds.

For the last decade, neuroscientists have studied the modulation of brain waves in patients with dementia, Alzheimer’s disease or other neurological or mental-health conditions to improve sleep, memory and cognition. “The scientific community believes that brain stimulation can indeed modulate the sleeping brain," said Roneil Gopal Malkani, an associate professor of neurology specializing in sleep at Northwestern Feinberg School of Medicine and the Jesse Brown Veterans Affairs Medical Center in Chicago. But Malkani cautions that using sound as a medical treatment is still being researched.

In one sleep study aimed at improving memory, Malkani gives patients pairs of associated words, such as “car" and “engine." Those who receive targeted bursts of sound delivered through headphones during the deepest phase of sleep have better memory the next day when they are given one word and asked to recall the second. The timing of the stimulation is guided by electroencephalogram, or EEG, a painless recording of the brain’s electrical activity using sensors attached to the scalp. While you’re awake, brain waves cycle at a speed of 8 to 12 hertz, but during the deepest phase of sleep, known as slow wave sleep, the cycle slows to 0.5 to 2 hertz—as few as one oscillation every two seconds.