Research

Brain-computer interfaces (BCIs) are also referred to as brain-machine interfaces (BMIs) and cortical neural prostheses.  Our particular focus is on creating new types of communication interfaces, and advancing their performance such that they are useful to people, by working directly with participants attempting to make rapid, dexterous motor sequences or speech movements. This is done as part of the BrainGate2 multi-site clinical trial (BrainGate2: Feasibility study of an intracortical neural interface system for persons with tetraplegia (NCT00912041), BrainGate.org, Timeline of some key BrainGate publications).

We investigate the underlying, fundamental human neuroscience (e.g., neural-population information representation and computations, often through the lens of dynamical systems) and fundamental engineering designs (e.g., machine-learning based decoder algorithms).  Our goals are to:

1. Measure voltage signals from large numbers of neurons simultaneously (i.e., action potentials from hundreds of individual neurons)
2. Do so with intracortical (neuro-surgically placed) electrode arrays where each electrode is mere microns from each neuron and thus maximum-available neural information is measured, in order to then
3. Deeply understand this neural information (basic systems and computational neuroscience) and
4. To create and demonstrate high-speed, highly-accurate and stable neural decoding algorithms that drive "high-bandwidth" communication between a person with paralysis (e.g., tetraplegia [1], anarthria [2]) and multiple computer and smart-home devices (e.g., mobile phones, tablets, computers, environmental control systems, doors).

Current projects include the fundamental neuroscience of dexterous movement, speech and language, and the design and system validation of high-performance and highly-robust communication BCIs. Some recent publications arising from our research projects:

1. Enabling control of digital devices via independent finger motion decoding (Willsey et al. Nature Medicine 2025).
2. A high-performance speech neuroprosthesis (Willett*, Kunz*, Fan* et al. Nature 2023).
3. High-performance brain-to-text communication via handwriting (Willett et al. Nature 2021).
4. Representation of the whole body in "hand" area of motor cortex (Willett*, Deo* et al. Cell 2020)
5. Control of 2D point-and-click cursors to help restore computer, tablet and phone operation: "2D point-and-click BCIs" (Pandarinath*, Nuyujukian* et al. eLife 2017, Nuyujukian et al. PLoS One 2018).

Our projects are generously supported by the National Institutes of Health (NIH) NIDCD, NINDS and BRAIN Initiative, the Simons Foundation, the Wu Tsai Neurosciences Institute and the Bio-X Institute.

[1] Tetraplegia (sometimes referred to as quadriplegia) is a term used to describe the inability to voluntarily move the upper and lower parts of the body. The areas of impaired mobility usually include the fingers, hands, arms, chest, legs, feet and toes and may or may not include the head, neck, and shoulders. This is caused by upper spinal cord injury (SCI), brainstem stroke and other neurological diseases and injuries.

[2] Anarthria is a severe form of dysarthria. Dysarthria is a motor speech disorder that occurs when someone can't coordinate or control the muscles used for speaking. People with dysarthria usually have slurred or slowed speech. People with anarthria, however, can't articulate speech at all. This is caused by neurological diseases and injuries including Amyotrophic Lateral Sclerosis (ALS) which is also known as Lou Gehrig's disease, Charcot's disease and Motor Neuron disease. ALS is a progressive neurodegenerative disorder.