Implicit versus explicit measures of emotion processing in people with aggressive tendencies and those who use pornography

Traditional clinical practice and research in the behavioural sciences has long relied on surveys and questionnaires to gather insight into an individual’s inner state of affect. Although this subjective data was once thought to provide a comprehensive understanding of an individual’s thoughts, feelings and emotions, recent research has shown that many mental processes and behaviours occur without conscious appraisal. The current project aimed to shed light on the literature surrounding findings of differences between non-conscious and conscious emotion-related processes by specifically looking at individuals in the normal population who self-report having varying amounts of aggressive tendencies and those who self-report as viewing varying amounts of pornography. The current project also aimed to determine whether controlled exposure of these groups to violent and pornographic images differently modulated conscious and non-conscious affective processes. To test this, we utilised the simultaneous collection of electroencephalography (EEG), electromyography (EMG) by way of Startle Reflex Modulation (SRM) and self-report data whilst participants were presented with emotion-inducing images acquired via the International Affective Picture System database (IAPS) across three recording sessions. Conscious explicit responses were determined via valence and arousal ratings to each of the images presented. Collectively, the results obtained presented a picture of differently modulated EEG activity predominantly across frontal and parietal electrode sites which varied between high and low aggression and pornography groups at baseline and was independent of conscious explicit responses and SRM. Furthermore, we were able to mimic the ERP physiological effects of high pornography use by the controlled exposure of violent and pornographic images to infrequent pornography users across sessions. Despite the ERP profiles showing variations across recording sessions, explicit responses remained constant. In sum, the findings of the current thesis provide insight into the confounds of simply relying on conscious subjective methods to understand emotional affect. Taken together the findings of the current thesis provide evidence to suggest clinicians and researchers may need to incorporate objective measures along with previously established subjective criteria to adequately determine a complete understanding of emotional affect in individuals.