Disgust is a vital emotion in the avoidance of illness. Human adults across cultures show disgust towards sources of potential contamination or pathogens, and elect to avoid their ingestion or even to look at them. Stomach rhythms appear to play an important role: disgust reduces normogastric power, and the pharmacological normalisation of gastric state reduces disgust avoidance. Human children are remarkably slow to develop disgust as measured by self-report and facial expressions. Here, we investigate whether disgust-induced avoidance (measured using eye tracking) and changes in gastric rhythm (measured using electrogastrography) exist in children aged 5 to 13 years (N = 45). We found that children in this bracket showed oculomotor avoidance of disgusting stimuli in a preferential-looking task, similar to adult samples in previous research. However, in contrast to adult samples in previous research, children did not show an attenuation in normogastric power. These findings could suggest that avoidance behaviour precedes gastric involvement during disgust. This would support the idea that children initially respond to parental modelling: parents set (and enforce) the social norm of disgust avoidance, and children initially conform and only later do they internalise disgust as an interoceptive signal. Alternatively, the employed stimuli could have been potent enough to induce oculomotor avoidance, but not a gastric response. Research is slim in this area, and future work should focus on elucidating the role of the stomach in disgust, and on longitudinal studies of disgust development from childhood to adolescence.
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