Oculesics refers to the study of eye contact and pupil dilation in terms of nonverbal communication.  Eye contact indicates interest, opennesss, and sometimes even arousal, though aggressive eye contact--or staring--can be interpreted as a sign of hostility.  In addition to this, lack of eye contact also transmits a message, oftentimes that the listener is bored and/or is not paying attention.  It must be noted that culture plays a role in oculesics, for the necessity of eye contact and the civility it provides in American culture differs greatly from an Asian culture, for example, where eye contact is often considered rude (DeFleur, 2005).