A team from Stanford and Michigan universities has enabled a paralyzed person to control a quadcopter using a brain-computer interface (BCI). This study was published in the journal Nature Medicine. BCIs are still imprecise, but the team led by neurosurgeon Matthew Willsey developed a BCI with a higher degree of movement precision and freedom than previously possible. The BCI was implanted in the precentral gyrus of a nearly completely paralyzed 69-year-old patient, referred to as T5. This part of the brain includes the motor cortex, responsible for movement control and hand and finger movements.
Initially, the interface had to be trained. The patient observed a virtual hand performing various movements and imagined doing the same with his own hand. The corresponding neural signals were recorded and analyzed using machine learning algorithms, or artificial intelligence. This allowed researchers to identify which signals corresponded to which finger movements.
The difference from previous studies was that the interface was not only designed for simple motor tasks like clicking a mouse or grasping an object but also to represent complex finger movements in multidimensional space, like those needed in video games or flying a quadcopter.
In subsequent tests, T5 was able to move three finger groups and the thumb of a virtual hand connected to the remote control of a virtual quadcopter using only the power of his thoughts. With just his thumb, he could steer the aircraft left, right, up, and down. The patient navigated the quadcopter through a predetermined obstacle course and spontaneously appearing rings. The system enabled navigation through or around 18 rings in less than three minutes, a sixfold performance improvement compared to previous systems. However, the system was not infallible; different finger groups were sometimes activated simultaneously, complicating control.
The patient, who had expressly wished to fly a quadcopter again, described the experience as playing a musical instrument: “Imagine you play the clarinet and pick up someone else’s instrument. You immediately notice it’s different, but thanks to your experience, you adapt accordingly.” He said the control of the aircraft was “more sensitive than fingers,” and he only needed to “tickle it in a direction.”
For Matthew Willsey and his colleagues, this research is a step towards involving paralyzed individuals more in leisure activities. Video games have become a litmus test for the capabilities of brain-computer interfaces. Elon Musk’s startup Neuralink recently introduced a BCI that reportedly allowed a patient to play Counter-Strike. A team from the University of Texas in Austin demonstrated that the brainwaves needed for gaming could be analyzed non-invasively using EEG caps.
These developments indicate the potential of BCIs to enhance the quality of life for individuals with severe motor impairments. While there are still challenges to overcome, such as improving precision and reducing unintended activations, the progress made so far is promising. As technology advances, BCIs may become a common tool for enabling greater independence and participation in various activities for those with disabilities.