are influenced by culture and context, but some components of emotional expression may be universal and independent of cultural overlays.
Motivated liars are easier to detect than nonmotivated liars. When emotionality is high, as in the case of tasks with high stakes associated with outcomes, nonverbal behaviors can be especially revealing. The revealing behaviors are likely to be those in a liar's unattended channels, which are leaked as a result of behavioral inhibition or rigidity.
Detectors, both amateurs and experts, are generally inaccurate despite high levels of confidence in their judgments. Neither feedback nor enhanced suspiciousness seems to improve their accuracy, but training them and providing them with a plan for processing information can increase accuracy of detection. The increased accuracy is more likely to occur if the discriminating cues to deception are known, and processing strategies aid the process of weighing and combining cues for judgments. In the absence of known relevant cues, whether to rely on possible universal or situation-specific cues remains an unresolved research issue.
Many questions are raised by the tantalizing information on deception and nonverbal behaviors. What nonverbal behaviors are associated with forms of deception that are not considered to be direct lies? What are the specific connections between nonverbal behaviors, emotions, and intentions as these occur in different situations? What are the implications of conscious control of facial expressions or body movements? There is a need to develop a framework that enables an analyst to match behaviors to situations in order to specify more precisely the contextual basis for behavior. What are the effects of varying types of lies and types of liars on the accuracy of detection? What are the dimensions of detection accuracy? There is a need to develop analytical strategies that aid the task of inferring intentions from behavior when the discriminating cues are not known. Cross-cultural studies of nonverbal behaviors associated with deception are needed. Little is known about the culturally specific display rules for every channel of communication, not only those manifest in facial expressions. On this topic, the gap between scientific evidence and anecdotal reporting is especially large. Researchers could take advantage of the large number of foreign students currently attending United States universities as a source for cross-cultural comparisons.
In spite of the number and breadth of unanswered questions, laboratory research does suggest particular aspects of behavior that may reveal intentions, for example, relationships between incongruities in verbal and nonverbal behaviors and stress, deviations from baseline observations of tone-of-voice as an indicator of possible deception, and an increased overall intensity of behaviors for extent of commitment to poli-