Brain-computer interface lets some unresponsive patients control a computer - Space and astronomy

A Columbia University team tested an EEG-based system with 41 intensive-care patients who could not communicate through speech or movement. Nearly one-third used brain activity to respond to audio instructions.

A brain-computer interface enabled some patients with acute brain injuries to control a computer using only their brain activity, according to a study published in Brain on October 22. The patients were conscious but unable to communicate through words or gestures.

Researchers at Columbia University placed 21 electroencephalogram (EEG) sensors on the heads of 41 unresponsive patients in intensive care. The team gave audio instructions asking them to try to open or close their hands, with the aim of changing the rhythm of a sound signal.

Although the patients could not carry out the instructions with physical movements, nearly one-third responded through their brain activity alone. Study coordinator Jan Claassen described it as the first study to show, in a relatively large group, that such patients can operate a computer through thought.

The research builds on work over the past two decades showing that some people in a coma, a vegetative state or a minimally conscious state retain the ability to understand motor instructions. This condition, known as cognitive motor dissociation, can be assessed using brain imaging and measurements of electrical brain activity; patients who show it are classified as CMD-positive.

Sources: Le Monde Sciences.