A brain-computer interface that decodes intended movements from motor cortex activity to control external devices such as computer cursors, robotic arms, or powered wheelchairs.

What category does Motor BCI belong to in BCI?

Motor BCI is a Applications concept in brain-computer interface science.

Motor BCI — BCI Glossary

A motor BCI reads neural signals from motor cortex — the brain region responsible for planning and executing voluntary movements — and translates them into commands for external devices. Motor BCIs are the most clinically advanced category of brain-computer interface, with multiple devices in human clinical trials for restoring movement and communication to people with paralysis.

Recording Targets

Motor BCIs typically record from:

Primary motor cortex (M1): Contains neurons that encode movement direction, velocity, and force. The hand-knob area of M1 is the most common recording target for cursor and arm control.
Dorsal premotor cortex (PMd): Encodes movement planning and preparation before execution. Signals from PMd can predict intended movements before they begin.
Supplementary motor area (SMA): Involved in movement sequencing and bilateral coordination.

Output Modalities

Cursor control: 2D cursor movement for computer interaction (the foundational motor BCI application)
Robotic arm control: 3D or higher-dimensional control of robotic arms for reaching, grasping, and manipulation
Functional electrical stimulation (FES): Decoded motor commands drive electrical stimulation of the user's own paralyzed muscles, restoring hand grasp and arm movement
Exoskeleton control: BCI-driven powered exoskeletons for walking and upper limb movement
Wheelchair control: BCI-directed powered wheelchair navigation

Clinical Systems

The major clinical motor BCI systems include:

BrainGate: Utah Array in motor cortex, Kalman filter decoder, wired percutaneous connector. The longest-running human motor BCI program.
Neuralink PRIME: N1 implant with 1,024 channels, wireless data and power, custom decoder. First human implant in 2024.
Synchron Stentrode: Endovascular BCI recording motor cortex signals through the superior sagittal sinus.

Performance

Motor BCI performance has improved dramatically. Early demonstrations (2004) achieved basic 1D cursor control. Current systems achieve multi-dimensional continuous control with throughputs exceeding 8 bits per second. The ReFIT Kalman filter (Gilja et al., 2015) approximately doubled clinical motor BCI performance, and deep learning decoders continue to push the frontier.