Figure 1: Open-loop and closed-loop BCIs
Open-loop BCIs extend a user’s ability to interact with external systems without altering neural activity itself. Closed-loop systems act directly on neural activity.
A Open-loop BCI
Record → interpret → act
Record 01
Captures neural activity
Interpret 02
Decodes signal into commands
Act 03
Drives external device Acts on the external world · examples
Moving a cursor on screen from thought Guiding a robotic arm via decoded motor intent Producing speech from decoded inner thought
B Closed-loop BCI
Record → interpret → stimulate → back to record
Record 01
Captures neural activity
Interpret 02
Decodes signal into commands
Stimulate 03
Modulates neural activity
Feedback loop
Acts on the brain · examples
Detecting and stopping a seizure automatically Strengthening memory recall Regulating mood and anxiety