A team at UC Davis and UC Davis Health has achieved a new milestone in brain-computer interface (BCI) technology by enabling a person with paralysis to control a computer cursor using brain signals associated with speech. The research, published in the Journal of Neuroengineering, was funded by the National Science Foundation and the National Institutes of Health.
The project involved engineers, neuroscientists, and neurosurgeons working together to expand the capabilities of BCIs, which are typically used to translate brain signals into speech. The team discovered that the area of the brain used for speech could also support cursor control, a function usually managed by a different region.
“Future steps in multimodal BCIs could include gesture decoding for all sorts of different things, enriching the types of interactions someone with paralysis can have with their environment beyond speech,” said Tyler Singer-Clark, a biomedical engineering Ph.D. student and first author on the paper.
Singer-Clark, a member of the UC Davis Neuroprosthetics Lab, built on previous work by the lab that produced a highly accurate speech BCI. The lab is co-directed by neuroscientist Sergey Stavisky and neurosurgeon David Brandman. Singer-Clark adapted existing software to allow cursor control using neural data from the speech motor cortex.
“We didn’t have to reinvent the pre-processing of the neural data,” Singer-Clark said. “For cursor control, it’s actually the same pre-processing steps the speech BCI uses to get the neural features that are going to be useful for decoding the intention of the participant.”
The new system was tested with a participant from the BrainGate clinical trial who has amyotrophic lateral sclerosis (ALS), a disease that causes loss of movement. The participant learned to move a computer cursor and select items on a screen using only his thoughts in less than 40 seconds.
Singer-Clark explained that the process is not about translating abstract thoughts into movement, but rather about intuition. “That’s his word, intuition,” Singer-Clark said. “I’ll say, ‘What motor imagery are you using?’ And he says, ‘Intuition.’”
Brandman highlighted the significance of this development: “Singer-Clark’s work is incredibly important for the field. His work has not only empowered our BrainGate2 participant to use a computer cursor with his thoughts but has also led the way for multiple companies in this space to design their clinical trials.”
The research suggests that complex, multimodal BCIs are possible and that movements may be represented across multiple areas of the motor cortex, not just isolated regions. Singer-Clark emphasized the personal impact of this technology: “There’s a man with ALS who can control his computer independently without someone else helping him for hours and hours every day. It’s like this great event, and we might not have tried if we didn’t have that prior research encouraging us to do that.”
The UC Davis team continues to develop technology aimed at increasing autonomy for people with paralysis.
