About the Electroencephalogram Lab

In our lab, stimuli are presented to participants via computer monitors. We use the BioSemi Active Two system to record EEG (electroencephalograph) activity. For more details on the Active Two system, please see http://www.biosemi.com/products.ht

Our caps have 66 electrodes attached. We also have 6 additional electrodes which are connected to the mastoid and ocular regions on the head and two fingers of one hand. The latter measures galvanic skin response (GSR).

The Active Two system uses active electrodes, where each electrode has a small amplifier attached to it, meaning we are able to use conductive gel in the recording of the EEG signals.

We have two testing rooms. The Itier (shown on the left) is actually a room within a room. The inner room, where the participant sits, is called a Faraday Cage and is deigned to block electronic signals from entering the testing area. This is important as the electrodes are very sensitive to any electronic signal. The Fugelsang lab (shown on the right) is a much simpler testing environment. Here we use wood as much as possible, again to help shield our electrodes from noise which could be transmitted by metal tables.

Galvanic skin response (GSR) is used to measure emotional reactions of a participant. As emotion levels change, skin conductance levels also change, so we are able to gain another measure of how participants are reacting to the stimuli presented to them. The collection techniques are the same as for the EEG recordings, meaning we are able to conduct combined EEG and GSR experiments, or use each method individually.