Mental imagery for brain-computer interface control and communication in non-responsive individuals

Area of Science:

• Neuroscience
• Biomedical Engineering
• Rehabilitation Medicine

Background:

• Severe brain damage can lead to prolonged disorders of consciousness or locked-in syndrome (LIS), where individuals are conscious but unable to move or speak.
• Brain-computer interface (BCI) techniques offer a potential method to detect neural correlates of conscious processing for communication in these patients.

Purpose of the Study:

• To evaluate the usability of a mental imagery task using a user-centered design approach.
• To assess the task's effectiveness in detecting voluntary information processing for communication in severely disabled individuals.

Main Methods:

• Five individuals with LIS participated, performing imagined hand, arm, or foot movements during electroencephalography (EEG).
• Event-related synchronization/desynchronization patterns were analyzed to detect task-associated brain activity.
• Usability was assessed based on efficiency, effectiveness, and user satisfaction.

Main Results:

• Two participants achieved significant accuracy in two distinct tasks.
• Users reported moderate workload and satisfaction, primarily influenced by the task's time commitment.

Conclusions:

• The mental imagery task demonstrated a lack of effectiveness in detecting voluntary brain activity for consciousness assessment or communication.
• Modifications are needed to improve user satisfaction and task effectiveness for non-responsive individuals.