Exploring Changes in Event-Related Potentials After a Feasibility Trial of Inhibitory Training for Bulimia Nervosa and Binge Eating Disorder

Abstract

In a feasibility trial comparing two forms of combined inhibitory control training and goal planning (i.e., food-specific and general) among patients with bulimia nervosa (BN) and binge eating disorder (BED), we found evidence of symptomatic benefit, with stronger effects among participants receiving a food-specific intervention. The aim of the present study was to examine changes in behavioral outcomes and event-related potentials (ERPs; N2 and P3 amplitudes) from baseline to post-intervention that might suggest the mechanisms underpinning these effects. Fifty-five participants completed go/no-go tasks during two electroencephalography (EEG) sessions, at baseline and post-intervention. The go/no-go task included "go" cues to low energy-dense foods and non-foods, and "no-go" cues to high energy-dense foods and non-foods. Datasets with poor signal quality and/or outliers were excluded, leaving 48 participants (N = 24 BN; N = 24 BED) in the analyses. Participants allocated to the food-specific, compared to the general intervention group, showed significantly greater reductions in reaction time to low energy-dense foods, compared to non-foods, by post-intervention. Commission errors significantly increased from baseline to post-intervention, regardless of stimulus type (food vs. non-food) and intervention group (food-specific vs. general). There were no significant changes in omission errors. P3 amplitudes to "no-go" cues marginally, but non-significantly, decreased by post-intervention, but there was no significant interaction with stimulus type (high energy-dense food vs. non-food) or intervention group (foodspecific vs. general). There were no significant changes in N2 amplitudes to "no-go" cues, N2 amplitudes to "go" cues, or P3 amplitudes to "go" cues from baseline to post-intervention. Training effects were only marginally captured by these event-related potentials. We discuss limitations to the task paradigm, including its two-choice nature, ease of completion, and validity, and give recommendations for future research exploring ERPs using inhibitory control paradigms.

A Pilot Event-Related Potentials Study on Mechanisms Underlying a tDCS-Enhanced Food-Specific Response Inhibition Task for Patients With Binge Eating Disorder

“…This is somewhat earlier than what has been found in previous studies (i.e. Lapenta et al, 2014;Biehl et al, 2020;Chami et al, 2020), but nevertheless within the normal range (see Luck, 2014).…”

“…For the N2 analyses, the stimulus locked epochs were used and consisted of the average of the three frontocentral sites: Cz, Fz, Fcz (Espinet et al, 2012). We determined a time window ranging from 100 to 250 ms after stimulus onset which is in line with previous studies (Leehr et al, 2018;Biehl et al, 2020;Chami et al, 2020). The peaks of the ERP, as well as the highest N2 activity located frontocentral/posterior (Cz), further matched this time window.…”

“…Neither of these interventions significantly changed the N2 or P3 amplitudes from baseline to post-intervention. These heterogenous findings imply that food-specific inhibition trainings might not change ERPs (Chami et al, 2020), but that tDCS could have an effect on ERPs (Lapenta et al, 2014). In the current pilot study, we aim to gain a more in-depth understanding of the potentially underlying neuropsychological mechanisms of inhibitory control in patients with BED.…”

“…In a subsequent Go/No-go task, decreased N2 negativity and significant increase in P3 positivity were found for No-go stimuli following active tDCS. Another study examined the behavioural and ERPs changes following a food-specific Go/Nogo task as inhibitory control training in patients with BN and BED in comparison to a control training (Chami et al, 2020). Neither of these interventions significantly changed the N2 or P3 amplitudes from baseline to post-intervention.…”

Conscious Self-Regulation, Level of Anxiety in Eating Disorders: A Structural Model

“…Eating disorders are the result of a complex interaction of constitutional, biological, social, and psychological factors. Research on eating disorders focuses on the role of mental disorders (Chami et al, 2020;Dawson et al, 2018;Palavras et al, 2020;Weiss et al, 2019) and sociocultural factors (Ordaz et al, 2018;Rodgers et al, 2018;2019Yamamiya et al, 2016). Currently, there are more and more studies that examine various types of mental self-regulation among the significant factors of nutritional behavior (Annesi et al, 2016;Dohle et al, 2018;Eschenbeck et al, 2016;Kennel, 2018;Menzie et al, 2017).…”