No abstract

The susceptibility of eyewitnesses to verbal suggestion has been well documented, although little attention has been paid to the role of nonverbal communication in misinformation. Three experiments are reported; in each, participants watched footage of a crime scene before being questioned about what they had observed. In Experiments 1 and 2, an on-screen interviewer accompanied identically worded questions with gestures that either conveyed accurate information about the scene or conveyed false, misleading information. The misleading gestures significantly influenced recall, and participants' responses were consistent with the gestured information. In Experiment 3, a live interview was conducted, and the gestural misinformation effect was found to be robust; participants were influenced by misleading gestures performed by the interviewer during questioning. These findings provide compelling evidence for the gestural misinformation effect, whereby subtle hand gestures can implant information and distort the testimony of eyewitnesses. The practical and legal implications of these findings are discussed.

Humans gesture even when their gestures can serve no communicative function (e.g., when the listener cannot see them). This study explores the intrapersonal function of gestures, and the semantic content of the speech they accompany. Sixty-eight adults participated in pairs, communicating on an object description task. Visibility of partner was manipulated; participants completed half the task behind a screen. Participants produced iconic gestures significantly more for praxic items (i.e., items with physically manipulable properties) than non-praxic items, regardless of visibility of partner. These findings support the semantic specificity hypothesis, whereby a gesture is integrally associated with the semantic properties of the word it accompanies. Where those semantic properties include a high motor component the likelihood of a gesture being produced is increased, irrespective of communication demands.

Individuals often receive judgements from others based on their clothing and their posture. While both of these factors have been found to influence judgements of competency independently, their relative importance in impression formation is yet to be investigated. We address this by examining interactive effects of posture and clothing on four competency measures: confidence, professionalism, approachability, and likeliness of a high salary. Participants rated photographs of both male and female models pictured in different postures (strong, neutral, weak) in smart clothing (a suit for males; both a trouser suit and skirt suit for females) and casual clothing. We confirm that posture manipulations affected judgements of individuals differently according to the clothing they were pictured in. The nature of these interactions varied by gender and, for women, competency judgements differed according to attire type (trouser or skirt suit). The implications of these findings in relation to impression formation are discussed.

Recent research has revealed that misinformation from gestures can influence eyewitness memory. However, it is still unclear whether gestural misinformation can emulate the effects of verbal misinformation on the reporting of major details in serious crimes. To investigate the salience of suggestions provided nonverbally, and how these compare to those made verbally, two experiments were conducted. In Experiment 1, participants watched footage of a crime scene and were presented with one of two types of gestures during questioning that suggested different interpretations of the crime. The results confirmed that the gestures influenced responses, with participants altering their interpretation of the crime according to the information gestured to them. Experiment 2 built on this to investigate how comparable gestural influence was to verbal influence. The results revealed that gestural misinformation caused participants to alter their interpretation of the crime and elicited the same effects as verbal misinformation. Across the two experiments, participants were unlikely to identify the misleading gestures or report feeling misled by them. These results reveal new insights into the strength of gestural misinformation and show that, despite their subtle nature in communication, gestures can exert a powerful influence in eyewitness interviews.