Deception and its detection is a complex, fluid, and cognitive process that is based on the context of the message exchange. The interpersonal deception theory posits that interpersonal deception is a dynamic, iterative process of mutual influence between a sender, who manipulates information to depart from the truth, and a receiver, who attempts to establish the validity of the message. A deceiver's actions are interrelated to the message receiver's actions. It is during this exchange that the deceiver will reveal verbal and nonverbal information about deceit. Some research has found that there are some cues that may be correlated with deceptive communication, but scholars frequently disagree about the effectiveness of many of these cues to serve as reliable indicators. Noted deception scholar Aldert Vrij even states that there is no nonverbal behavior that is uniquely associated with deception. As previously stated, a specific behavioral indicator of deception does not exist. There are, however, some nonverbal behaviors that have been found to be correlated with deception. Vrij found that examining a "cluster" of these cues was a significantly more reliable indicator of deception than examining a single cue.