Types of Brain-Computer Interfaces
Ways to classify BCIs
Two useful categories
BCIs can be grouped by whether they are invasive or non-invasive, and by whether they are active, reactive, or passive. Another common way is by purpose: communication, control, rehabilitation, or monitoring.
Purpose-based categories
| Category | What it does | Example use |
|---|---|---|
| Communication | Helps users express messages | Spelling or typing |
| Control | Operates a device | Cursor or prosthetic movement |
| Rehabilitation | Supports recovery training | Motor therapy |
| Monitoring | Measures brain state | Attention or fatigue tracking |
Not all BCIs do the same job
Some systems help a person send messages, while others are mainly used to observe or study brain activity.
Examples of use
Common applications
A BCI may help someone select letters on a screen, move a wheelchair cursor, or interact with software using brain-related patterns. Other systems may simply measure mental workload or sleep-related signals.
Which is a communication use of a BCI?
Communication BCIs help users express information.
Correct answer: Typing a message by selecting letters
Name one purpose of a BCI besides communication.
BCIs can also be used to operate devices, support therapy, or track brain state.
Correct answer: Control, rehabilitation, or monitoring.
Which category best fits a system that tracks attention levels?
Monitoring BCIs observe brain state rather than directly controlling a device.
Correct answer: Monitoring