How embarrassing! The behavioral and neural correlates of processing social norm violations

Abstract

Social norms are important for human social interactions, and violations of these norms are evaluated partly on the intention of the actor. Here, we describe the revised Social Norm Processing Task (SNPT-R), a paradigm enabling the study of behavioral and neural responses to intended and unintended social norm violations among both adults and adolescents. We investigated how participants (adolescents and adults, n = 87) rate intentional and unintentional social norm violations with respect to inappropriateness and embarrassment, and we examined the brain activation patterns underlying the processing of these transgressions in an independent sample of 21 adults using functional Magnetic Resonance Imaging (fMRI). We hypothesized to find activation within the medial prefrontal cortex, temporo-parietal cortex and orbitofrontal cortex in response to both intentional and unintentional social norm violations, with more pronounced activation for the intentional social norm violations in these regions and in the amygdala. Participants' ratings confirmed the hypothesis that the three types of stories are evaluated differently with respect to intentionality: intentional social norm violations were rated as the most inappropriate and most embarrassing. Furthermore, fMRI results showed that reading stories on intentional and unintentional social norm violations evoked activation within the frontal pole, the paracingulate gyrus and the superior frontal gyrus. In addition, processing unintentional social norm violations was associated with activation in, among others, the orbitofrontal cortex, middle frontal gyrus and superior parietal lobule, while reading intentional social norm violations was related to activation in the left amygdala. These regions have been previously implicated in thinking about one's self, thinking about others and moral reasoning. Together, these findings indicate that the SNPT-R could serve as a useful paradigm for examining social norm processing, both at the behavioral and the neural level.

Fig 1. Overview of the revised Social Norm Processing Task (SNPT-R).

During the story-reading phase (1), participants read stories consisting of a stem sentence and an ending sentence, describing either a neutral social situation, a situation in which a social norm was unintentionally transgressed or situation in which a social norm was violated intentionally. Participants were instructed to imagine themselves in the situation described. In the rating phase (2), participants rated all stories on embarrassment and inappropriateness.

Fig 2. Behavioral ratings on the SNPT-R (n = 87, behavioral sample).

Stories describing intentional social norm violations were rated as more inappropriate and more embarrassing when compared to stories on unintentional social norm violations, while unintentional stories were considered more inappropriate and more embarrassing in comparison to neutral stories. Boys rated the stories as less inappropriate when compared to men and women; women rated the stories as more embarrassing in comparison to the other groups. Data are presented as means ± SD. *: p ≤ 0.05; **: p ≤ 0.01; ***: p ≤ 0.001.

Fig 3. Significant activation clusters related to processing stories describing social norm violations.

Clusters are superimposed on the template MNI_T1_152_2mm_brain (partial brain coverage; inferior parts of the frontal medial cortex and superior parts of the postcentral gyrus are not included). All images are displayed according to radiological convention: right in image is left in brain.