Palm readings – what can neuromarketers learn from galvanic skin response?
Everyone knows the classic sign of nervousness in sweaty palms during a first date or a big client presentation (and for the unlucky few, sweaty everything else), but did you know we can learn so much more about you with that? Galvanic Skin Response (GSR) is a way of measuring your level of emotional arousal (be it unbridled joy or abject horror) based on electrodermal activity, that being the continuous variation in electrical potential difference between the surfaces of your fingertips.
How does it work?
Your autonomic nervous system is best known for the “fight or flight” response. Given how critical it is to flee or fight as soon as possible in a survival situation, the autonomic nervous system must work incredibly fast the moment you see anything that could be a threat (heighten your emotions). Among other responses, the sympathetic branch of the autonomic nervous system causes you to sweat, which increases conductance of the skin (or increased electrical potential difference).
This skin conductance is an indication of psychological or physiological arousal or, for example, the degree of intensity of your excitement or fear. These days, however, humans aren’t exactly running from tiger attacks, so most of the signals the sympathetic nervous system gives are much smaller – maybe you’re excited about a new iPhone release or irritated with an app’s poor navigation. As a result, the amount you sweat due to emotional arousal is often imperceptible to you, but perfect for GSR measurements.
In measuring GSR, we place two electrodes either on your fingers or on your wrist and measure the conductivity of the skin between them (you don’t feel a thing). When you sweat, even slightly, the conductivity of your skin changes and we know that you’ve just seen or experienced something that changes your state of emotional arousal.
Pros and Cons
GSR provides useful insight into the moment-to-moment emotional state of someone in response to whatever you place in front of them, be it tasks, products, copy, webpages, etc. The equipment is easy to set up and transport, making it ideal for work in the field, such as assessing levels of emotional arousal during in-store shopping experiences.
Because emotional arousal is such a broad term and can denote anything from joy to rage, it’s important to pair this technology with other measures so you can also assess the nature of the emotional arousal, be it a positive or negative response. Here’s where the measures of emotional affect (as in the type of emotion being experienced; for example, happiness or disgust, anger or contempt) are useful in providing much needed context of the consumer experience.
When setting up a GSR experiment, it’s important to bear in mind a couple of issues. First, the slight time delay between the stimulus being measured and the response – there is always variability in responses in terms of time, which can be as much as a few seconds. Some people are slow responders, while others are faster. This can make it difficult to aggregate the results. However, there are nice workarounds to these problems, developed by physiologists and neuroscientists.
Research participants moving their hands a lot may produce artefacts or false readings in the GSR, since physical activity results in sweat. It’s therefore important to be able to differentiate between change in conductance caused by actual arousal and that caused by activity. Lastly, large changes in environmental temperatures are also known to produce false readings or artefacts in GSR recordings. All these challenges can be managed by implementing good baseline control tests as part of the study design.
Why do we enjoy music when, functionally, it is a series of tones that serves no purpose towards our survival? A research group in 2009 used GSR to attempt to answer that question. They found that, when people listened to their favourite music as opposed to music they didn’t enjoy, they had heightened physiological arousal to match their increased emotional arousal. This suggests that enjoying music has physically pleasurable effects on the body, and begins to answer the question of why we enjoy it so much.