A female participant in the locked-in study
A computer interface that can decipher the thoughts of people who are unable to communicate could revolutionize the lives of those living with completely locked-in syndrome, according to a paper published this week in PLOS Biology.
And contrary to expectations, the participants in the study reported being “happy,” despite their extreme condition. The research was conducted by a multinational team, led by Niels Birbaumer, at the Wyss Center for Bio and Neuroengineering in Geneva.
Patients suffering from complete paralysis, but with preserved awareness, cognition, and eye movements and blinking are classified as having locked-in syndrome. If eye movements are also lost, the condition is referred to as completely locked-in syndrome.
In the trial, patients with completely locked-in syndrome were able to respond “yes” or “no” to spoken questions, by thinking the answers. A non-invasive brain-computer interface detected their responses by measuring changes in blood oxygen levels in the brain.
The results overturn previous theories that postulate that people with completely locked-in syndrome lack the goal-directed thinking necessary to use a brain-computer interface and are, therefore, incapable of communication.
Extensive investigations were carried out in four patients with ALS (amyotrophic lateral sclerosis, also known as Lou Gehrig’s disease) — a progressive motor neuron disease that leads to complete destruction of the part of the nervous system responsible for movement.
The researchers asked personal questions with known answers and open questions that needed “yes” or “no” answers including: “Your husband’s name is Joachim?” and “Are you happy?” They found the questions elicited correct responses in 70% of the time.