Robust single‐trial event‐related potentials differentiate between distress and fear disorders

Abstract

Recent evidence indicates that measures of brain functioning as indexed by event‐related potentials (ERPs) on the electroencephalogram align more closely to transdiagnostic measures of psychopathology than to categorical taxonomies. The Hierarchical Taxonomy of Psychopathology (HiTOP) is a transdiagnostic, dimensional framework aiming to solve issues of comorbidity, symptom heterogeneity, and arbitrary diagnostic boundaries. Based on shared features, the emotional disorders are allocated into subfactors Distress and Fear. Evidence indicates that disorders that are close in the HiTOP hierarchy share etiology, symptom profiles, and treatment outcomes. However, further studies testing the biological underpinnings of the HiTOP are called for. In this study, we assessed differences between Distress and Fear in a range of well‐studied ERP components. In total, 50 patients with emotional disorders were divided into two groups (Distress, N = 25; Fear, N = 25) according to HiTOP criteria and compared against 37 healthy comparison (HC) subjects. Addressing issues in traditional ERP preprocessing and analysis methods, we applied robust single‐trial analysis as implemented in the EEGLAB toolbox LIMO EEG. Several ERP components were found to differ between the groups. Surprisingly, we found no difference between Fear and HC for any of the ERPs. This suggests that some well‐established results from the literature, e.g., increased error‐related negativity in OCD, are not a shared neurobiological correlate of the Fear subfactor. Conversely, for Distress, we found reductions compared to Fear and HC in several ERP components across paradigms. Future studies could utilize HiTOP‐validated psychopathology measures to more precisely define subfactor groups.

Transdiagnostic psychopathology in the light of robust single‐trial event‐related potentials

“…At first sight, this conclusion contradicts the results from our previous study, where the Distress patients with a primary ICD-10 diagnosis of depression and GAD-had a significantly reduced CRN compared to healthy comparison subjects (Randau et al, 2023). However, group-level differences between HiTOP subfactors based on primary ICD-10 diagnosis do not necessarily translate to correlations with transdiagnostic symptomatology.…”

“…In that study, the patient group had a significantly increased ERN compared to the healthy comparison group. For our present sample, we have recently shown that a subsample based on the HiTOP subfactor Distress-containing the ICD-10 diagnoses of Depression and GAD-had a reduced ERN at baseline compared to healthy comparison subjects (Randau et al, 2023). In that study, the ERN of the Fear subfactor-containing agoraphobia, OCD, PD, and SADwas not significantly different to either the Distress or HC group.…”

“…However, we cannot rule out that a desensitizing effect across sessions took place for the patient group, essentially decreasing the perceived threat of errors and thereby the ERN. That being said, patients showed a reduced ERN compared to HC already at baseline and the ERN has been shown to be stable across sessions (Olvet & Hajcak, 2009a;Randau et al, 2023). Neither can we rule out a fatigue effect from the rather long paradigm, even though such an effect has not been demonstrated (Olvet & Hajcak, 2009b).…”