A brain-computer interface, implanted in a participant with tetraplegia (total paralysis of the arms and legs), enabled remarkable control over a virtual quadcopter by merely imagining the movement of his inactive fingers.
This innovative technology segments the hand into three groups: the thumb, and two pairs of fingers (index and middle, ring and little). Each section can be maneuvered both vertically and horizontally. When the participant thinks about moving the three groups, sometimes all at once, the virtual quadcopter reacts, skillfully navigating through a digital obstacle course.
This advancement represents a thrilling opportunity for individuals with paralysis to enjoy multiplayer games and also illustrates the potential for engaging in remote work.
“This technology enables a level of control greater than anything that has previously been achieved with finger movements,” remarked Matthew Willsey, assistant professor of neurosurgery and biomedical engineering at the University of Michigan, and lead author of the recent study published in Nature Medicine. The research detailed in the paper was carried out while Willsey was at Stanford University, where many of his colleagues are based.
While there are non-invasive methods for enhancing video game interactions, such as using electroencephalography (EEG) to capture signals from the scalp, these EEG signals reflect activity from large brain regions. The researchers believe that to restore precise motor control, electrodes must be placed closer to the actual neurons. The study reports a sixfold improvement in quadcopter performance by capturing signals directly from motor neurons instead of through EEG.
The process to set up this interface involves a surgical operation, where electrodes are implanted in the motor cortex of the brain. These electrodes connect to a pedestal secured to the skull, which crosses the skin to link with a computer.
“The device captures signals generated in the motor cortex whenever the participant attempts to move their fingers and employs an artificial neural network to decipher their intentions for controlling virtual fingers in a simulation,” explained Willsey. “Then, we communicate signals to manage a virtual quadcopter.”
This research was part of the BrainGate2 clinical trials, exploring how neural signals can work alongside machine learning to create new ways for people with neurological impairments to control external devices. The participant began collaborating with the Stanford research team in 2016, after a spinal cord injury rendered him unable to use his limbs. He was eager to assist with the research, particularly interested in aviation.
“The choice of a quadcopter simulation was intentional, as the participant had a strong interest in flying,” stated Donald Avansino, co-author and computer scientist at Stanford University. “This platform not only satisfied his desire for flight but also demonstrated finger control capabilities.”
Nishal Shah, incoming professor of electrical and computer engineering at Rice University and co-author of the study, noted, “Controlling fingers is just a starting point; our ultimate aim is to restore full-body movement.”
According to Jaimie Henderson, a Stanford neurosurgery professor and co-author of the study, the significance of this research goes beyond gaming—it fosters human connections.
“People often emphasize the restoration of basic functions like eating, dressing, and mobility, which are indeed vital,” he explained. “However, other critical elements of life, such as recreation and social interaction, are often overlooked. People desire to play games and engage with their friends.”
He added that someone capable of controlling a virtual vehicle using solely their thoughts could eventually achieve much more.
“When able to manipulate multiple virtual fingers through brain control, a range of multi-faceted control possibilities emerge for various applications,” Henderson noted. “This could include anything from using CAD software to creating music.”
Researchers Nick Hahn, Ryan Jamiolkowski, Foram Kamdar, and Francis Willett from Stanford, along with Leigh Hochberg from Brown University, also contributed to this study.
CAUTION: Investigational Device. Restricted by Federal law for investigational purposes.
