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Updated: Sep 7, 2025
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Isometric and Eccentric Force Generation Assessment of Skeletal Muscles Isolated from Murine Models of Muscular Dystrophies
Published on: January 31, 2013
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More What Duchenne Smiles Do, Less What They Express.
Eva G Krumhuber1, Arvid Kappas2
1Department of Experimental Psychology, University College London.
Summary
The Duchenne smile (DS) may not solely indicate positive emotions. Research suggests DSs can be deliberately used without genuine positive feelings, challenging their role as direct emotion signals.
Area of Science:
- Psychology
- Nonverbal Communication
- Facial Expression Analysis
Background:
- The Duchenne smile (DS) is often considered a reliable indicator of genuine positive emotion.
- Sheldon et al. (2021) proposed that DSs signal the presence and intensity of positive emotion, as well as chronic positive mood.
Approach:
- This commentary critically re-examines the literature cited by Sheldon et al. to support their hypotheses.
- We analyze the empirical evidence regarding the association between Duchenne smiles and felt positive affect.
Key Points:
- The reviewed literature supporting the link between Duchenne smiles and positive affect is largely inconclusive, irrelevant, incomplete, or misinterpreted.
- No single empirical study unanimously supports the claim that Duchenne smiles exclusively indicate felt positive affect.
- Evidence suggests Duchenne smiles can be consciously produced and displayed without accompanying positive feelings.
Conclusions:
- The assertion that Duchenne smiles solely signify positive emotions is not empirically supported.
- Duchenne smiles may be employed deliberately, irrespective of the individual's emotional state.
- A functional perspective, focusing on the actions of facial expressions like Duchenne smiles rather than their purported expressive content, is proposed.
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