Over the past few years, there has been a steady influx of startups trying to treat issues like depression, period pain, PMS , anxiety and insomnia by using wearables that apply electrical, magnetic or ultrasonic signals to stimulate the brain. San Francisco-based Mave Health is the latest of that fleet, and claims its $495, neuromodulation headset can improve attention and mood, regulate stress, and even measure mental health. The startup is positioning the wearable as a non-medical device so