Factors affecting the accurate detection of trait aggression from gait
Student thesis: Doctoral Thesis
This thesis extends the limited extant research on interpersonal threat detection accuracy. Broadly speaking, it was found that when viewing video presentations of walking targets, observers could accurately detect the trait aggression of those targets. The thesis opens with a summary of the relevant background literature and the general foci of this programme of research (Chapter 1). Chapter 2 explains why movement is important for recognising aggression. Using biomechanical analyses of gait, Chapter 2 provides evidence that individuals’ dispositional aggression is related to how they walk, thus highlighting the importance of gait in detecting potential aggressors. The third Chapter outlines two experiments that demonstrate that: i) judgments of the threat posed by targets correlate with the self-reported trait aggression of the targets; and ii) these judgments of threat are most accurate when movement information is available. Chapter 4 attempts to answer the ever-present question throughout this thesis; what makes a good judge? In an eye tracking experiment, it was shown that more accurate judges of aggression are those who, when observing a video of a target walking, spend more time observing the body and legs (and not the face) of the targets. Chapters 5 and 6 investigate how age affects the accuracy of detecting trait aggression. Chapter 5 highlights that accuracy for recognising trait aggression is acquired with age. Participants from the age of 13 years were tested for aggression detection accuracy and the results show that accuracy greatly improves after the age of 18 years. The results of the experiment outlined in Chapter 6 illustrate that accuracy is maintained into older age, with participants up to the age of 91 years performing similarly to young adults. The seventh Chapter explores the methodological pitfalls of previous trait recognition research. The analyses presented in Chapter 7 show how the typical reporting of trait recognition studies: i) overestimates the size of accuracy effects;ii) ignores the variance in individual judge’s ability to recognise traits; and iii) does not acknowledge the influence of individual targets on overall accuracy values. The thesis closes with a general discussion (Chapter 8), overviewing the findings and implications(both applied and theoretical) of the current work, as well as directions for future work.