Making eye contact signals to another person that you are paying attention. And it triggers the limbic mirror system, a set of brain areas that are active both when we move any part of the body (including the eyes) and when we observe someone else doing the same.
Direct eye contact, or mutual gaze, is an essential tool we use to communicate with others. While maintaining eye contact, we can convey a host of emotions and messages to the onlooker. Looking directly at someone while theyre speaking indicates to the speaker that youre listening and paying attention.
Hence why when we pass strangers we will often automatically glance at their faces. A field study on a university campus in the US found that making eye contact with strangers leaves us feeling more socially connected, whereas if someone avoids our gaze, we are more likely to feel disconnected.
Eye Contact Is a Two-Way Street: Arousal Is Elicited by the Sending and Receiving of Eye Gaze Information. Research shows that arousal is significantly enhanced while participants make eye contact with a live person compared to viewing a picture of direct or averted gaze.