ArticleScientific reports2026
A smiling mouth expression modulates gaze appearance by enhancing how the eyes light up.
Article in Scientific reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Research on composite facial expressions has shown that a smiling mouth, when combined with neutral eyes, can influence how the eyes are interpreted. From a gestalt-oriented perspective, we propose that smiling not only affects emotion recognition but also produces a fascinating, compelling visual counterpart: an enhancement of the eyes' apparent luminosity, or 'lighting up'. We tested this hypothesis in two within-subject experiments by collecting ratings of perceived eye brightness and smile intensity for whole faces, as well as for eyes and mouths presented isolated. In Experiment 1, we combined neutral eyes with neutral, slightly smiling, and fully smiling mouths. Results show that, for each stimulus, eye brightness ratings increased as a function of smile intensity. In Experiment 2, we combined neutral and Duchenne-smiling eyes with neutral and smiling mouths. Data analysis reveals that a smiling mouth significantly enhances the luminosity ratings of Duchenne-smiling eyes compared to their own perceptual baseline (individual eyes presented alone). Furthermore, a neutral mouth appears to 'dim' the brightness of Duchenne-smiling eyes. Through further pictorial demonstrations, we suggest that this phenomenon is remarkably robust, occurring in naturalistic photographic portraits, pareidolic faces and paintings. We propose that this subtle yet compelling effect represents a perceptual signature of the gaze, intensifying facial aliveness as the mouth modulates the eyes' appearance. Mirroring the relational logic of the Wollaston illusion, our findings demonstrate that the eyes and mouth operate in synergy, forming a unified expression where the visual system integrates individual features into a harmonious and living whole.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.