Measuring Attention and Disgust with Eye-Trackers

How can you tell when someone is disgusted? Perhaps you can tell by the way they wrinkle their nose and look away, or by the auditory “EW” elicited when looking at something unpleasant. Other times, it may not be as noticeable to discern a person’s emotion. In order to account for all of the nuances of emotions, affective research has come up with novel ways to assess emotional expressions and responses through self-measured reports and objective bodily reaction measurements such as skin conductance, heart rate, brain activity, and eye-tracking. 

At the DIS lab in Stockholm, my research partner and I are making use of our access to the eye-tracking technology available to gain a better understanding of the relationship between disgust and attention. Specifically, we are interested in how the participant’s pupil dilation and fixation duration can reveal their reaction to disgusting stimuli and whether their attention is drawn toward a clean versus dirty image. Our study focus is on primary disgust (disgust for body products, animals, hygiene, etc. rather than for moral or social ideas), and we predicted that being exposed to a disgusting image would attenuate participant’s attention toward a clean image in order to alleviate the aversive state. This is consistent with the account that disgust is a disease-avoidance mechanism in which the feeling of disgust could heighten awareness and avoidance of pathogen threats and contaminants that pose harm to the immune system. 

Our experiment design includes priming participants with either a disgusting or neutral prime before having them do a visual scan between a dirty and clean matched image. For the disgusting primes, we selected pictures that would evoke primary disgust such as feces and rotten food, and we generated random numbers (i.e. 926585) for the neutral primes in order to have them be completely unrelated to the clean images shown in the matched pairs. The matched pair were selected to be as similar in context as possible (i.e. dirty toilet versus clean toilet, or used mask versus clean mask); the same paired images were left/right reversed and presented on both sides (in different blocks) to account for positional effects. Participants were told to do a pseudo-key-pressing task to keep their attention on the screen for optimal eye-tracking measurements. After the eye-tracking trials, participants completed a COVID-19 behavior and attitude survey to assess their personal beliefs and practice in regards to maintaining hygiene against pathogens. Although we are still in the process of collecting data (the main issue being the lack of participants available), it is interesting to see (purely observational, the data has not been analyzed yet) that many tend to fixate on the gross elements of the stimuli more so than its cleaner counterpart. I am excited to see whether our data will prove our hypothesis wrong, and hopefully, we will be able to recruit enough participants to run a decent analysis.