active in their attempt to deceive than most would anticipate or expect. IDT was developed in 1996 by David B. Buller and Judee K. Burgoon. Prior to their study, deception had not been fully considered as a communication activity. Previous work had focused upon the formulation of principles of deception. These principles were derived by evaluating the lie detection ability of individuals observing unidirectional communication. These early studies found initially that "although humans are far from infallible in their efforts to diagnose lies, they are substantially better at the task than would result merely by chance." Additionally, research has shown that deception and suspected deception occurs in at least one quarter of all conversations. Buller and Burgoon discount the value of highly controlled studies – usually one-way communication experiments – designed to isolate unmistakable cues that people are lying. Therefore, IDT is based on two-way communication and intended to describe deception as an interaction communicative process. In other words, deception is an interpersonal communication method that required the active participation of both the deceiver and receiver. Buller and Burgoon wanted to emphasize that both the receiver and deceiver are active participants in the deception process. Both are constantly engaged in conscious and unconscious behaviors that relay their true intentions. Buller and Burgoon initially based their theory of IPD on the four-factor model of deception developed by social psychologist Miron Zuckerman, who argues that the four components of deceit inevitably cause cognitive overload and therefore leakage. Zuckerman's four factors include the attempt to control information, which fosters behavior that can come across as too practiced, followed by physiological arousal as a result of deception. This arousal then leads to the third factor, felt emotions, which are usually guilt and anxiety, which can become noticeable to an observer. Additionally, the many cognitive factors and mental gymnastics that are going on during a deception often lead to nonverbal leakage cues, such as increased blinking and a higher pitched voice. Propositions IDT's model of interpersonal deception has 21 verifiable propositions. Based on assumptions of interpersonal communication and deception, each proposition can generate a testable hypothesis. Although some propositions originated in IDT, many are derived from earlier research. The propositions attempt to explain the cognition and behavior of sender and receiver during the process of deception, from before interaction through interaction to the outcome after interaction. Context and relationship IDT's explanations of interpersonal deception depend