EEGs measure brain activity by recording fluctuations in electrical signals.
Different brain wave frequencies on EEGs correspond to different mental states like sleep, relaxation, alertness, and conscious perception.
Consumer-grade EEG devices are noisier than clinical ones but can still provide useful insights into brain activity, especially for applications like monitoring drowsiness or stress.
Noninvasive brain activity imaging allows for measuring and mapping brain activity without surgery or bulky machines.
Different imaging modalities like fNIRS, functional ultrasound, and portable MEG offer varying levels of convenience, spatial resolution, and depth of brain activity detection.
Innovations like functional ultrasound and OPM-MEG show promise in providing noninvasive and portable options for measuring brain activity.