title: The mechanisms of action of cognitive bias modification for appetitive behaviours and associated disorders
Creators: name: Di Lemma, LC
Publisher: name: University of Liverpool Repository
Year: 2017

description: The current thesis investigated Cognitive Bias Modification (CBM) for appetitive behaviours and associated disorders, specifically alcohol and chocolate consumption. In a series of experiments, I investigated (1) the effectiveness and (2) the psychological and psychophysiological mechanisms of action of Cue Avoidance Training (CAT) and Inhibitory Control Training (ICT). Specifically, I investigated if CAT and ICT are equally effective at reducing alcohol consumption in the laboratory and if these effects could be replicated in a more ecologically valid setting with ‘real-word’ environmental triggers. Furthermore, I investigated the neural correlates of CAT and tested psychological accounts of the mechanisms that underpin CBM, specifically stimulus-response associations, devaluation and several alternative hypotheses. In the first experimental chapter (Chapter Two) I compared the effects of alcohol CAT and ICT on alcohol consumption in the laboratory, while at the same time investigating whether effects on alcohol consumption could be explained by stimulus-response associations or devaluation. Results showed that both interventions were equally effective for the reduction of alcohol consumption, and these behavioural effects were accompanied by changes in stimulus-response associations, but not devaluation. Chapter Three replicated the effects of ICT on alcohol consumption in a lounge laboratory, although exposure to alcohol advertisements greatly reduced their magnitude. Chapter Four used electroencephalography (EEG) to investigate the neural correlates of CAT during preparatory approach and avoidance motor responses, and demonstrated changes in components of the event-related potential associated with engagement of executive control (N200) and attentional processing (Late Positive Potential). In Chapter Five, results from two experiments suggest that automatic approach, impaired inhibitory control and automatic affective associations for chocolate-related stimuli are not related to each other, which further casts doubt on the notion that changes in stimulus evaluation underlie the effects of these forms of CBM. The experiment reported in Chapter Six demonstrates that ICT leads to changes in attention and choice for alcohol-related stimuli, but no devaluation effects (assessed with self-report), which again casts doubt on the devaluation hypothesis. Finally, the experiment described in Chapter Seven suggests that ICT leads to the formation of stimulus-response associations, but not changes in signal detection. To conclude, this thesis contributes new data which suggests that the effects of CAT and ICT on alcohol and chocolate consumption and choice are robust and are most likely to be explained by formation of stimulus-response associations during training rather than devaluation of appetitive stimuli or alternative mechanisms. Future research should attempt to optimize the behavioural effects of these interventions by exploring techniques to strengthen the formation of stimulus-response associations.