Human behavior research can begin even at the surface of the skin. Galvanic skin response (often known as electrodermal activity, or EDA), is a unique way to investigate how our physiological activity can change and fluctuate in response to stimuli.
The amount of electrical current change at the surface of our skin increases when we are physiologically or emotionally aroused, and is ultimately under the control of the autonomic nervous system.
This means that it can provide critical information about how someone feels, and also can’t be consciously controlled, making it an insightful, and unbiased measure of how someone feels.
Knowing how aroused someone is in response to stimuli is particularly powerful when combined with other metrics that can determine emotional valence, or attentional processes, as it provides a new dimension to results and findings.
Getting it right however is the important part. While a fairly straightforward methodology, there are still several critical steps that should be followed to guarantee success with your GSR research.
That’s why we’re put together our top five recommendations for ensuring high quality GSR data – meaning you can have even more confidence in the results.
Read on to learn more about the essentials for perfect GSR research.
Typically, the electrodes are attached to the index and middle finger. It is also possible to place the electrodes in other locations (such as the shoulders, or even feet). The electrodes should be placed on the proximal part of the finger (i.e. not the joint), with the electrodes placed on the palm side of the hand.
If you’re also measuring heart rate during the experiment, then place the electrode for heart rate on the ring finger.
GSR sensitivity is different to EMG recordings. This means that unlike with EMG, you don’t need to clean the skin before recording can take place. This makes GSR measurements a quicker process to get up and running with.
Make sure that there is nothing obstructing the GSR electrodes (e.g. a ring) – anything that obstructs the device will of course impede the signal.
This applies not only for the electrode, but the device as a whole if it is wireless. To guarantee a strong continuous signal, you should try to maintain a relatively clear path from the device and the dongle on the computer.
Ensure the participant can move around if they need to, or are required to. If the participant has to use their hands (e.g. using a mouse), then ensure that it is attached to the hand that is not being used, or consider attaching electrodes to another location, such as the shoulders, or a foot.
Inform the respondent to move their hands as little as possible, if this is where the electrodes are attached.
Ensure that the GSR device is kept at least 30cm away from the computer to reduce interference from the electrical noise. However, if the device is wireless, ensure that the Bluetooth signal doesn’t drop off by making sure that the respondent doesn’t move too far away from the dongle at the computer.
The good news with GSR is that you don’t need to carry out a calibration prior to collecting data – as long as it’s properly connected then your data will be good. The bad news is that there isn’t a built-in check for the data prior to recording.
One of they ways that you can quickly check the validity of the data is to ask the respondent to breath in and out rapidly (or hold their breath) – this should have a positive effect on the skin conductance, which you will be able to see live in iMotions.
These are our essentials for getting human behavior research using GSR right. To get an even deeper understanding of the processes underlying GSR, then download our free pocket guide below.