Completely Locked in Syndrome Patients Able to Communicate in Brain-Computer Interface Breakthrough

Wednesday 1st February 2017

Researchers at the University of Turbigen in Germany have reported that four patients suffering from Completely Locked-in Syndrome (CLIS) have been able to communicate the answers to known personal questions using a brain-computer interface that uses infrared light to measure blood flow within the brain and translates it into “yes” and “no” responses.

Published in the Public Library of Science Biology open journal, the results, aimed at breaking the complete loss of communication that affects sufferers of locked-in syndrome, particularly those who are in a completely locked-in state, which is defined by the report as someone paralysed to the extent that they cannot communicate in any way externally, with even twitches and eye movements made impossible. The experiment focused on four patients with amyotrophic lateral sclerosis (ALS) who either were completely locked in or had no reliable way to communicate.

In order to confirm and calibrate the device, personal questions of which the answers were known were presented to the patient in random order. In total, twenty questions are asked in each nine minute session, with blood flow and brain waves measured for each question. The questions were asked repeatedly in order to confirm that the devices were correctly measuring the equipment each time, and the results confirmed the correct responses were elicited in 70% of the sessions.

Many of the questions were personal questions with known answers, however one patient, Patient B was able to communicate disapproval of his daughter’s engagement.

His family requested that the researchers ask if he approved of his daughter marrying her boyfriend, which on nine occasions was answered negatively.

The implication of this study is the astonishing conclusion that people who are in a completely locked-in state are capable of communication, which challenges conventional scientific views that CLIS patients are unable to use even a brain computer interface.

The potential for communication with a cognitively functioning person in a locked in state using such a device has clear implications on their lives and quality of life. Offering the option of communication even in the case of complete paralysis effectively eliminates the completely locked-in state, as there will always be an option for communication. The research into brain-computer interfacing is currently at a very early stage, so it is currently unclear how far this technology can go and indeed, what insights can be gathered about how communication works from a mental process.

Further breakthroughs in the actual technology used are also of note. This particular experiment used functional near-infrared spectroscopy (fNIRS) as well as more standard electroencephalogram (EEG) electrodes, which by themselves have been used in previous attempts to create communication methods for locked-in syndrome sufferers.

There are potential for advancement even beyond offering communication; the Wyss Centre in Geneva noted their plans to use this technology as part of plans to create technology that can be used to help people suffering from paralysis to regain movement, considering it a “crucial first step”