Most low to mid range EEG is 'passive'. The electrodes are connected by wires directly to the amplifier. This works fine in most cases and has been the standard for decades.
'Active' electrodes have a small pre-amplifier directly behind the electrode. This is especially helpful if the electrode material is a conductive rubber material. Such materials conduct voltage less efficiently than standard gold, silver, or silver chloride electrodes. So the pre-amp, makes up for the lower conductivity. This in turn allows for softer / bendable / comb type electrodes to be used.
'Active' means the electrode itself contains a small amplifier, or actually it is more accurately termed a pre-amp. Typically the pre-amp is in a tiny circuit board behind the surface of the electrode. After pre amplification, the wires lead to the main amplifier box or PC board.
The 3M pre-gelled, adhesive electrodes, as used with OpenBCI are passive. But it is conceivable that another type of EEG amplifier, could have snap on actives that mate with the 3M or other types of snap-ons.
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BCI, hi.
Most low to mid range EEG is 'passive'. The electrodes are connected by wires directly to the amplifier. This works fine in most cases and has been the standard for decades.
'Active' electrodes have a small pre-amplifier directly behind the electrode. This is especially helpful if the electrode material is a conductive rubber material. Such materials conduct voltage less efficiently than standard gold, silver, or silver chloride electrodes. So the pre-amp, makes up for the lower conductivity. This in turn allows for softer / bendable / comb type electrodes to be used.
https://shop.openbci.com/collections/frontpage/products/thinkpulse-active-electrode-kit
William
So using the thinkpulse kit would be active, but using the 3m red dot would be passive?
'Active' means the electrode itself contains a small amplifier, or actually it is more accurately termed a pre-amp. Typically the pre-amp is in a tiny circuit board behind the surface of the electrode. After pre amplification, the wires lead to the main amplifier box or PC board.
The 3M pre-gelled, adhesive electrodes, as used with OpenBCI are passive. But it is conceivable that another type of EEG amplifier, could have snap on actives that mate with the 3M or other types of snap-ons.