AlterEgo doesn’t read your thoughts, but it can enable you to communicate with your computer without touching a keyboard or opening your mouth. To use the headset to carry out a simple task like Googling the weather on your laptop, first formulate the query in your mind. The headset’s sensors read the signals that formulation sends from your brain to areas you’d trigger if you had said the query aloud, like the back of your tongue and palate. Then, via a web connection, the device, designed by researchers at the MIT Media Lab, carries out the task on your laptop. To inform you of the results of the task, the headset uses a bone conduction speaker that only you can hear. Researchers found that the device’s prototype was able to understand its wearer 92% of the time. The interface is currently being tested in limited hospital settings, where it helps patients with multiple sclerosis and ALS to communicate.