‘We Read Emotions Based on How the Eye Sees’, https://www.psychologicalscience.org/news/releases/we-read-emotions-based-on-how-the-eye-sees.html, ASSOCIATION FOR PSYCHOLOGICAL SCIENCE (February 22, 2017).
Findings show that how we see directly relates to how others see us, through our facial expressions. (…) Finding underscores how the origins of reading mental states from the eyes relate in part to how the eyes see. (…) Human expressions are highly complex — when enumerating our facial muscles, we computed that there are at least 3.7 x 1016 different expression combinations. (…) Looked at a subset of this space — just the eye region — (…) found that one simple physical dimension (widening vs. narrowing) explained a majority of this complex space in social communication.