Food-Induced Emotional Resonance Improves Emotion Recognition

Abstract

The effect of food substances on emotional states has been widely investigated, showing, for example, that eating chocolate is able to reduce negative mood. Here, for the first time, we have shown that the consumption of specific food substances is not only able to induce particular emotional states, but more importantly, to facilitate recognition of corresponding emotional facial expressions in others. Participants were asked to perform an emotion recognition task before and after eating either a piece of chocolate or a small amount of fish sauce-which we expected to induce happiness or disgust, respectively. Our results showed that being in a specific emotional state improves recognition of the corresponding emotional facial expression. Indeed, eating chocolate improved recognition of happy faces, while disgusted expressions were more readily recognized after eating fish sauce. In line with the embodied account of emotion understanding, we suggest that people are better at inferring the emotional state of others when their own emotional state resonates with the observed one.

Fig 1. Visual representation of the Experimental Procedure.

In an initial phase participants were asked to fill out two questionnaires and to perform four rating judgments. I. First session of the Emotion Recognition Task. II. Food ingestion: one group of participants was asked to eat ~5gr of dark chocolate, whereas the other group was asked to ingest a spoonful of fish sauce. After food intake participants were asked to perform an emotion intensity judgment. III. Second session of the Emotion Recognition Task, followed by another emotion intensity judgment and IOS rating scale. The faces depicted in this figure are not the original ones from the KDEF dataset, but are mere examples. The individuals have given written informed consent (as outlined in PLOS consent form) to publish their faces.

Fig 2. Results for the Emotion Recognition Task.

Graphs showing performance on the emotion recognition task, before and after either dark chocolate (top panel) or fish sauce (bottom panel) intake. Accuracy in recognizing angry, disgusted or happy facial expressions were measured (percentage of correct responses, y axis). Error bars reflect standard error of the mean, and asterisk indicates p < 0.05, two-tailed.

Fig 3. Results for the Emotion Recognition Task.

Graphs showing performance on the emotion recognition task, before and after either dark chocolate (top panel) or fish sauce (bottom panel) intake. Mean Reaction Times (msec, y axis) in recognizing angry, disgusted or happy facial expressions were measured. Error bars reflect standard error of the mean, and asterisk indicates p < 0.05, two-tailed.