Learning to detect deception from three communication channels

A Lie Detection Test—a videotape of senders delivering truthful and deceptive messages—was administered to subjects via one of three channels: Face only, speech only, or face plus speech. Feedback information, identifying the messages as truthful or deceptive, was given to some subjects (learning condition) but not to others (control). It was found that subjects in the learning condition performed better overall relative to control subjects, regardless of the channel presented to them. In addition, however, accuracy of subjects in the learning condition improved progressively over the course of the test (relative to control), for the speech only and face plus speech channels but not for the face only channel. This effect was interpreted in terms of the limited number of deception cues offered by the face.