New Device Turns Thoughts into Speech

For the first time, scientists have successfully played back a word someone was thinking by monitoring their brain activity. This milestone could lead to people’s intended thoughts being transferred to an electronic speaker or writing device.

For those suffering from diseases that prohibit the communication of thoughts, like those suffering from strokes or Lou Gehrig’s disease, this could change lives.

Professor Robert Knight and colleagues at UC Berkeley are leading the research by studying how “hearing words, speaking out loud and imagining words involves overlapping areas of the brain.”

The scientists first placed electrodes on the surface of the language areas of the brain in patients who were awake. They monitored the pattern of electrical responses of brain cells during perceived speech. After, a computer model was created that could match spoken sounds to these thought signals, taking into account differences in sound timing. They could then decode speech when a person thinks of a specific word, from direct brain recordings. The data was collected from patients who were scheduled for neurosurgery for a non-related reason (like treating epilepsy).

Knight explains,

We applied a temporal realignment procedure that improved our accuracy in classifying words that are spoken or imagined. Our work showed us it is possible to capture the brain signals that represented an intended word.

The goal is to one day create an effective, implantable wireless prosthetic recording device that can be utilized in everyday life.

Knight says,

We want to develop an implantable device that decodes the signals that occur in the brain when we think about a word, then turn these signals into a sound file that can be reproduced by a speech device.