Even without seeing the messenger, we can pick up each other’s body language, say researchers. Source: Technology Networks
Emotions such as heightened arousal can make pupils dilate. Belladonna (or deadly nightshade) was once used by women to dilate their pupils, thus making them seemingly more attractive.
Source: Wade, N. J. & Swanston, M. T. (2013), Visual Perception. An Introduction. 3rd edition, London, Taylor and Francis Group.
