Researchers at Osaka University are stepping up efforts to develop robotic body parts controlled by thought, by placing electrode sheets directly on the surface of the brain. Led by Osaka University Medical School neurosurgery professor Toshiki Yoshimine, the research marks Japan’s first foray into invasive (i.e. requiring open-skull surgery) brain-machine interface research on human test subjects. The aim of the research is to develop real-time mind-controlled robotic limbs for the disabled, according to an announcement made at an April 16 symposium in Aichi prefecture.
Although brain waves can be measured from outside the scalp, a stronger, more accurate signal can be obtained by placing sensors directly on the brain — but that requires open-skull surgery, making it more difficult to recruit volunteer test subjects.
The researchers, who have filed a license application with the Osaka University Hospital ethics board, are working to enlist willing subjects already scheduled to have brain electrodes implanted for the purpose of monitoring epilepsy or other conditions. The procedure, which does not involve puncturing the cortex, places an electrode sheet at the central sulcus, a fold across the center of the brain near the primary motor cortex (which is responsible for planning and executing movements).
To date, the researchers have worked with four test subjects to record brain wave activity generated as they move their arms, elbows and fingers. Working with Advanced Telecommunications Research Institute International (ATR), the researchers have developed a method for analyzing the brain waves to determine the subject’s intended activity to an accuracy of greater than 80%. The next step is to use the data to control robot arms developed by the University of Tokyo’s Department of Precision Engineering.