A recent study published in the Current Biology, says that people often assume that others are staring at them even when no one is looking at them.
It is natural for humans to judge when others are looking at you. Explaining this gaze perception, researchers from the University of Sydney say that the brain makes the perception based on the visual information like direction of the head and eyes.
However, when there isn't sufficient information, brain makes its assumptions based on previous experiences. Researchers tested this theory by creating images of faces and asking people to observe the faces. They had made it difficult for the people to see where the eyes of the face were looking. Most of the people said that the faces were staring at them.