Experimental Investigation of Non-Verbal Communication in Eating Disorders

This study aimed to be the first to measure non-verbal communication in 25 eating disorder (ED) and 25 non-ED control participants during a naturalistic social interaction incorporating positive, negative and neutrallyvalenced topics. The first hypothesis, that ED participants would show significantly reduced facial emotional expression than controls, was not supported. Supporting the second hypothesis of between-group differences in non-verbal behaviour, ED participants were less likely to lean in towards their interlocutor (d=.81) discussing negatively-valanced topics and were more likely to be positioned upright when discussing positively-valenced topics (d=.1.09) than controls. Irrespective of emotional valence, ED participants positioned their gaze on their interlocutor significantly less (d=.29) and spent more time looking down (d=.54), or away than controls (d=.63). ED participants moved their hands along with speech significantly less (d=.63) and gestured fewer real/ hypothetical/imagined images/actions/objects) than controls (d=.57), irrespective of emotional valence. Instead, ED participants indicated discomfort in the social interaction, touching their nose (d=.89) or playing with their nails (d=.95) more often than controls. ED participants, regardless of emotional valence, showed significantly lowered electro-dermal activity (d=.60) than controls, supporting the exploratory hypothesis. People with EDs appear to make less efficient use of non-verbal communication than controls.

Automated summary

This study found that individuals with eating disorders exhibit less efficient use of non-verbal communication compared to control participants, including leaning in less towards their interlocutor, gesturing less, and showing signs of discomfort during social interactions.