About one in three unresponsive ICU patients controlled a tone with EEG

A Columbia team tested a noninvasive brain-computer interface in 41 clinically unresponsive ICU patients after acute brain injury. Routine EEG recorded brainwaves while a bedside computer analyzed them in real time; patients heard instructions to try opening and closing their hands and used that mental effort to change the frequency of a tone in headphones. After brief training, about one in three controlled the sound through thought alone, including every patient whose cognitive-motor dissociation was found in a separate exam. The group had previously detected hidden consciousness in 15% of unresponsive brain-injury patients in 2019. This system still provides simple feedback, not free communication, and is not routine clinical care. Larger studies must test accuracy, fatigue and individual variation before patients can reliably express pain, hunger or basic wishes.