These conductive gels and pastes are formulated specifically for measurement of EEG from the scalp, but may be used to measure other biopotentials such as EOG, EMG, and even ECG. … Gels are generally dispensed into openings in an electrode cap or onto individual electrodes with a syringe.

Why do we use gel in EEG?

This is the main reason why gel is so common; the gel provides contact between the scalp and each electrode that greatly reduces impedance. Otherwise, high impedance will impair signal quality and increase vulnerability to electrical artifact, such as from external devices or movement.

What adhesive is used for EEG?

EEG testing over several days involves gluing electrodes to the scalp. The standard glue hospitals and other services around the world use is called collodion. Collodion is preferred over other adhesives because it is extremely strong and durable for day-to-day wear.