Brain-computer interface (BCI) research is a rapidly evolving field with growing clinical interest for systems that allow patients suffering from neurological disorders to independently interact with their environment.
Past innovations include using signals acquired from chips implanted in the brain for robotic device control. However, the substantial medical and surgical expertise required to correctly install and operate these implants have limited their use to a few clinical cases. In the US, researchers from Carnegie Mellon University in collaboration with the University of Minnesota have made a breakthrough in addressing this problem by developing a non-invasive robotic device control system that continuously tracks and follows a computer cursor.
Future of BCI technology
BCI technology sends and receives signals between the brain and an external device. By using electroencephalograms (EEGs), the researchers were able to non-invasively acquire signals deep within the brain and achieve the neural control of a robotic arm. A discrete target paradigm composed of following fixed target locations and a continuous pursuit task involving the sustained tracking of a target were utilised. The technology has successfully been tested on 68 subjects, with each subject partaking in up to 10 sessions and accurately causing a cursor to move with their thoughts.
Previous non-invasive human-controlled robotic arms often resulted in erratic motions. However, this new system allowed the arm to follow the cursor in a continuous path, enhancing accurate tracking by over 500%. The continuous pursuit task produced stronger behavioural and psychological learning effects. The researchers were also able to overcome the poor signal concerns that are typically associated with noninvasive systems including EEG by using spatial filtering.
The non-invasive control of robotic devices using only thoughts will have wide applications with great benefits for patients with movement disorders. The researchers plan to conduct further clinical trials in the near future.