An investigation into concurrent approach bias modification and transcranial Direct Current Stimulation for binge eating disorder

Student thesis: Doctoral ThesisDoctor of Philosophy


Background: Binge eating disorder (BED) is the most prevalent eating disorder worldwide. Conventional treatments (e.g., cognitive behavioural therapy) are not well suited to targeting automatic cognitive processes which can contribute to food cravings and associated maladaptive cognitions/ behaviours in BED. Two emerging treatments that aim to modify relevant neurocognitive processes are investigated: Approach Bias Modification training (ABM), a computerised training programme that aims to reduce the strength of an implicit approach bias to food, and transcranial Direct Current Stimulation (tDCS), a form of non-invasive brain stimulation. Both strategies have separately shown potential as treatment adjuncts to reduce binge eating. The aim of this research is to investigate the feasibility and therapeutic utility of ABM and tDCS delivered as a combined treatment intervention for BED.

Methods: An overview of BED is presented, including a critical appraisal of the existing research on the diagnosis, aetiology and treatment options for BED. A systematic review of the literature of the efficacy of ABM applications for appetitive and addictive stimuli was conducted. The feasibility and therapeutic efficacy of ABM and tDCS was investigated via a multi-session feasibility randomised controlled trial (RCT), in addition to a qualitative interview study with a subgroup of RCT completers.

Results: Collectively, quantitative and qualitative findings indicate that the concurrent delivery of ABM and tDCS was an acceptable and feasible treatment intervention. While findings lack significance, positive changes for key outcome measures across eating disorder symptomology and related neurocognitive features were found for participants who engaged in ABM paired with real or sham tDCS. There was evidence of a superior therapeutic effect of ABM and real tDCS over ABM and sham tDCS in facilitating a reduction in participants’ BMI, however, there was no further evidence of an enhancement effect of tDCS for the additional clinical and neurocognitive outcomes measured.

Conclusions: This research includes the first RCT of concurrent ABM and tDCS for BED. Findings offer preliminary support for this novel treatment intervention and inform theoretical, practical and ethical issues around the use of combined brain-targeted treatments for eating disorders.

Date of Award1 Jun 2022
Original languageEnglish
Awarding Institution
  • King's College London
SupervisorIain Campbell (Supervisor) & Ulrike Schmidt (Supervisor)

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