Background: In treatment-resistant major depressive disorder (MDD), electroconvulsive therapy (ECT) is a treatment with high efficacy. While knowledge regarding changes in brain structure following ECT is growing, the effects of ECT on brain function during emotional processing are largely unknown. Objective: We investigated the effects of ECT on the activity of the anterior cingulate cortex (ACC) and amygdala during negative emotional stimuli processing and its association with clinical response. Methods: In this non-randomized longitudinal study, patients with MDD (n ¼ 37) were assessed before and after treatment with ECT. Healthy controls (n ¼ 37) were matched regarding age and gender. Functional magnetic resonance imaging (fMRI) was obtained twice, at baseline and after six weeks using a supraliminal face-matching paradigm. In order to evaluate effects of clinical response, additional posthoc analyses were performed comparing responders to non-responders. Results: After ECT, patients with MDD showed a statistically significant increase in ACC activity during processing of negative emotional stimuli (p FWE ¼ .039). This effect was driven by responders (p FWE ¼ .023), while non-responders showed no increase. Responders also had lower pre-treatment ACC activity compared to non-responders (p FWE ¼ .025). No significant effects in the amygdala could be observed. Conclusions: ECT leads to brain functional changes in the ACC, a relevant region for emotional regulation during processing of negative stimuli. Furthermore, baseline ACC activity might serve as a biomarker for treatment response. Findings are in accordance with recent studies highlighting properties of pretreatment ACC to be associated with general antidepressive treatment response.

Heightened impulsivity and compulsivity are often found in association with both dysfunctional everyday behavior as well as with psychopathology. Impulsivity and compulsivity are also linked to alterations in behavioral response inhibition and its electrophysiological correlates. However, they are rarely examined jointly and their effect outside of clinical samples is still disputed. This study assesses the influence and interaction of impulsivity and compulsivity as measured by questionnaires on behavioral performance and event-related potentials (N2, P3a and P3b) in a visual Go/Nogo task. Data from 250 participants from the general population (49% female; age M = 25.16, SD = 5.07; education level: 94% high school or higher; self-reported lifetime diagnosis of any mental disorder: 12%) were collected. We used robust linear regression as well as regression tree analyses, a type of machine learning algorithm, to uncover potential non-linear effects. We did not find any significant relationship between the self-report measures and behavioral or neural inhibition effects in either type of analysis, with the exception of a linear effect of the premeditation scale of the UPPS on behavioral performance. The current sample size was large enough to uncover even small effects. We discuss potential explanations for this current null finding. One possibility is that inhibitory performance was unimpaired in the current sample and that associations between inhibitory performance and self-report measures might only be seen in samples with mental disorders.

Heightened impulsivity and compulsivity are often found in association with both dysfunctional everyday behavior and with psychopathology. Impulsivity and compulsivity are also linked to alterations in behavioral response inhibition and its electrophysiological correlates. However, they are rarely examined jointly and their effect outside of clinical samples is still disputed. This study