How Computers Measure Brain Activity
Ways to collect brain data
Non-invasive methods
Some systems measure activity from outside the body. Examples include EEG, which records electrical activity from the scalp, and fMRI, which measures changes related to blood flow. These methods are safer and easier to use, but usually less precise.
Invasive methods
Other systems use sensors placed closer to or inside the brain. These can capture more detailed signals, but they require surgery and raise more medical and ethical concerns.
Non-invasive vs invasive
Non-invasive
- Easier to use
- Usually safer
- Often lower signal detail
Invasive
- Higher signal detail
- Requires surgery
- Greater medical risk
Important distinction
Better signal quality often comes with greater risk. Real-world design is always a tradeoff between usefulness, safety, and comfort.
Which method records electrical activity from the scalp?
EEG measures electrical patterns from electrodes placed on the scalp.
Correct answer: EEG
Why might invasive sensors be chosen in some systems?
Sensors closer to brain tissue can often capture richer information.
Correct answer: They can provide more detailed signals