Consumer brain recording technologies make all sorts of claims that are simply not substantiated in the literature at the level of individual predictions.
(Source: Tara Thiagarajan, SapienLabs)
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.
