Summary: New research suggests that more expressive facial behaviour helps people form stronger social bonds. By analyzing hundreds of natural conversations, researchers found that individuals who move their faces more dynamically are judged as more likeable, easier to read, and often better at achieving social goals such as negotiating or managing disagreement.
The study measured facial expressivity during real interactions and linked those measures to partner impressions and outcomes. Results indicate that facial expressivity is a stable individual difference with clear social benefits.
Key Facts:
- Facial expressivity correlates with greater likeability and better social outcomes.
- Researchers examined semi-structured interactions and a large set of unscripted video conversations to assess natural facial behaviour.
- Automated Facial Action Coding System (FACS) analysis was used to quantify facial muscle activity and expressivity.
Source: Nottingham Trent University
Overview of the research
Researchers set out to evaluate whether variation in how people use their facial muscles during everyday conversation affects social impressions and outcomes. The work combined detailed observation, automated coding, and impression ratings to test whether facial expressivity supports social bonding and negotiation.
In the initial phase, researchers conducted semi-structured video calls with 52 volunteers, using a confederate to prompt a range of everyday behaviours: listening, humour, embarrassment, and disagreement. Calls included specific tasks such as maintaining a neutral face while the partner attempted to elicit a reaction, testing participants’ ability to inhibit facial display.
Later, the same participants recorded short video clips in which they deliberately tried to achieve social objectives—looking friendly, appearing intimidating, or expressing disagreement without provoking dislike. Those clips, together with excerpts from the original calls, were rated by 176 independent observers who judged emotions, clarity of expression, and likeability.
Facial movements were quantified using the Facial Action Coding System (FACS), which tracks the activation of facial muscles to produce objective indices of expressivity. The researchers combined these measures with self-reports and partner impressions to examine links between facial behaviour, personality traits, and social outcomes.
To broaden the scope, the team ran a follow-up analysis on a much larger collection of unscripted video conversations—more than 1,300 interactions from an established dataset—where conversation partners provided likeability ratings of one another. This larger-scale analysis replicated the core findings: people who exhibited greater facial expressivity were generally liked more by both independent observers and by the people they interacted with.
Beyond likability, expressivity related to social competence in negotiation contexts. In a scenario where participants faced an unfavourable payment offer, those who combined agreeableness with pronounced facial expressivity tended to secure better outcomes, suggesting that expressivity can aid in resolving conflicts and reaching advantageous agreements.
The study also found that facial expressivity showed considerable stability across contexts and time for individuals, implying it is a consistent personal trait rather than a momentary state. Expressivity correlated with personality measures such as agreeableness, and in larger samples, with extraversion and emotional reactivity.
Dr Eithne Kavanagh, lead author and research fellow at Nottingham Trent University’s School of Social Sciences, noted that this is the first large-scale investigation of facial expression in real-world interactions and that the evidence points to social advantages for more expressive individuals. The research is part of an interdisciplinary European Research Council project (FACEDIFF) led by Professor Bridget Waller, which explores the social functions, anatomical basis, and evolutionary origins of facial expression.
Professor Waller commented that these findings may help explain why humans evolved complex facial musculature—nuanced facial signals appear to support affiliative behaviour, strengthen bonds, and help people navigate the social world more effectively.
About this social and evolutionary neuroscience research news
Author: Helen Breese
Source: Nottingham Trent University
Contact: Helen Breese – Nottingham Trent University
Image: Image credit: Neuroscience News
Original Research: Open access. “Being facially expressive is socially advantageous” by Eithne Kavanagh et al., published in Scientific Reports.
Abstract (summary)
This work examined individual differences in dynamic facial behaviour across social interactions and related those differences to dyadic outcomes and impression formation. In a controlled study of semi-structured interactions and a larger analysis of unstructured video calls, facial expressivity was measured via automated FACS analysis. Results show stable individual variation in facial behaviour that is consistently associated with greater likeability, perceived readability, and advantages in negotiation and social bonding. These findings support an affiliative, adaptive function for human facial expressivity.