Example image of eyePlorer eyePlorer map for 'Facial feedback hypothesis': Charles Darwin William James Robert Zajonc Silvan Tomkins Corrugator Zygomaticus major muscle Galvanic skin response Stimulus (physiology) Correlation Cover story Cognition Orbicularis oculi muscle Risorius Scientific control Demand characteristics Annual Reviews (publisher) Journal of Personality and Social Psychology Psychological Review GNU Free Documentation License QI (F series)