Locked-In Syndrome

Locked-in syndrome is a rare neurological condition in which a person is fully conscious and cognitively aware but unable to move or speak due to complete paralysis of nearly all voluntary muscles, often resulting from a brainstem stroke or injury. People with locked-in syndrome typically retain only vertical eye movements and blinking, making these their sole means of communication without assistive technology. Brain-computer interfaces (BCIs) and eye-tracking systems are critical assistive technologies for this population, enabling access to communication devices and the web.