AbstractBinge eating disorder (BED) is common, yet treatment options are suboptimal. Novel treatments may yield better outcomes than established approaches if they directly target the mechanisms involved in the maintenance of BED. Neurobiological models have implicated altered cognitive control, and recent studies have indicated that attention bias (AB) towards high-calorie food may be a potent target for treatment. Accordingly, interventions that directly target cognitive control functions have been developed. These include attention bias modification training (ABMT), a computerised training programme that aims to reduce the strength of an implicit AB towards high-calorie food cues, and transcranial direct current stimulation (tDCS), a non-invasive brain stimulation (NIBS) technique that uses direct current electric fields to alter cortical excitability and enhance neuroplasticity. Independently, both ABMT and tDCS have been reported to produce therapeutic effects in patients with BED, however, it is proposed that the effects of tDCS may be enhanced when disorder-related brain regions are activated during stimulation, and that the effects of ABMT may be improved when neuroplasticity is greater. Thus, outcomes from treatment may be superior when tDCS and ABMT are combined.
To better understand the potential for tDCS to influence AB, we first reviewed the literature relating to the effects of NIBS on AB towards emotion. Here, we reveal that, although the evidence is mixed, findings in clinical populations generally suggest that AB may be altered by NIBS. In parallel, a cross sectional study of food-related AB in obesity with and without BED examined the extent to which AB was a distinct feature of BED. We observed that both groups showed AB towards high-calorie food cues, but that only participants with BED showed a bias towards low-calorie food cues, and that the relationship between craving and food-related AB was greatest in BED. Accordingly, we conducted a feasibility trial of concurrent at-home tDCS with ABMT in adults with BED. Findings indicated that the study protocol is feasible, and that the intervention is acceptable. Moreover, tDCS with ABMT was associated with reductions in objective binge eating behaviour, craving, and AB towards high-calorie food stimuli which were maintained to follow-up. As a result, concurrent tDCS with ABMT is a promising novel option for treatment, and future trials of this approach are encouraged.
|Date of Award||1 Jun 2023|
|Supervisor||Ulrike Schmidt (Supervisor) & Iain Campbell (Supervisor)|