1. BusinessInsider has a great collection of pictures tracking where people actually look when they see an image. (Big takeaway: men love to look at other people’s groins.)
2. Watch the video above: people generally look at the face of the person talking or the object that someone is pointing at. Why? Because that is where the information resides.
3. If you ask someone to look for a hidden target, they will look around in a manner that will give them the most information about where the target may be – this lets them exclude as many locations as possible.
4. But we are social animals, and social animals have a tendency to rely on social information – gathering information from other individuals lets you pass on some of the cost of finding it to others. Humans in crowds will look where other humans are looking – what is going on over there? is it something important? why are so many people looking?
5. Of course, humans in crowds are also wary. Other social creatures are potential threats: you want to look someone else’s face to determine whether they are friendly or not. Many animals (like peacocks!) do this – look at where predators might be hiding. Because what information is more important?
6. One way that the nervous system accomplishes this is by internal reward: it is ‘enjoyable’ to look at social faces (and the more relevant, the more rewarding).
7. Famously, dogs will look at where people are looking while cats will not; one has evolved to understand this social information while the other has not. Which says a lot about the psychology of a cat!
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Gallup AC, Chong A, Kacelnik A, Krebs JR, & Couzin ID (2014). The influence of emotional facial expressions on gaze-following in grouped and solitary pedestrians. Scientific reports, 4 PMID: 25052060
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