When we use the same pathways to represent "self" and "other", there are bound to be mixups. But not unlike Ghostbusters, when pathways are crossed or overreact, weird things start to happen. 

Mirror-touch Synesthesia is an extremely rare mental condition in which a person's empathy centers are overactive, not only making them acutely feel the emotions of other people, but they also feel every action they see (Banissy, Kadosh, Maus, Walsh, & Ward 2009).

 

Do you feel a touch on your cheek when you watch this video? You may have a mirror-touch synesthesia...

In a study from Banissy and Ward in 2007, researchers found that when people with mirror-touch synesthesia viewed a video of someone’s cheek being touched, they felt that same touch themselves on their own skin.

 

Imagine feeling hugs given to someone else, feeling food inside your mouth when you see other people eating, and feeling personal anguish when you see someone crying.

 

It can be unnerving to think that another persons’ actions could cause such an effect on your own body. Since it is such a rare condition, there are a number of possible explanations for this interesting phenomenon, which directly correspond to representations of "self" and "other" in the brain.