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DePamphilis, G.

Publications and source records attributed to DePamphilis, G..

2 recordsLinked to original sources

Heightened Distraction under Competition in Obsessive-Compulsive Disorder

The present study examine the extent to which attentional resources are allocated toward distracting affective and disorder-relevant pictures under task-relevant competition in participants with obsessive-compulsive disorder (OCD; N = 33) and controls (N = 31). Competition between cues was examined using a foreground task where participants detected coherent motion in a flickering random dot kinematogram (RDK) overlaid on pictures ranging in emotional content (pleasant, neutral, unpleasant, and OCD-evoking pictures). Steady-state visual evoked potentials (ssVEPs) were measured in response to the flickering RDK and served as an index of visuocortical engagement with task-relevant cues. Data were also fitted to the distraction under competition model (DUC), a computational framework of attention selection. Group differences emerged with stronger visuocortical distraction (attenuated task engagement) in the OCD group, driven largely by the unpleasant pictures, followed by the OCD-evoking and pleasant pictures. Furthermore, the DUC model fit well in both groups and supported the results of the univariate analysis, demonstrating the magnitude of the visuocortical distraction observed in response to the unpleasant pictures, and the presence of substantial distraction in response to the OCD-evoking pictures in the OCD group. The present findings provide visuocortical evidence of heightened distraction in response to unpleasant and OCD-evoking pictures under task-relevant competition in OCD.

neuroscience↗

Dysfunctional oscillatory bursting patterns underlie working memory deficits in adolescents with ADHD

Identifying neural markers of clinical symptom fluctuations is prerequisite to developing more precise brain-targeted treatments in psychiatry. We have recently shown that working memory (WM) in healthy adults is dependent on the rise and fall interplay between alpha/beta and gamma bursts within frontoparietal regions, and that deviations in these patterns lead to WM performance errors. However, it is not known whether such bursting deviations underlie clinically relevant WM-related symptoms or clinical status in individuals with WM deficits. In adolescents (n=27) with attention deficit hyperactivity disorder (ADHD), we investigated WM-related dynamics between alpha/beta and gamma bursts in relation to clinical status fluctuations. Participants repeatedly completed a visual Sternberg spatial working memory task during EEG recording as part of their participation in two research studies (n=224 person-sessions). Source localizing EEG data to each participants structural MRI, the rate and volume of alpha, beta, and gamma bursts were examined within the dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex (PPC). Alpha/beta and gamma bursts at the DLPFC and PPC displayed complimentary roles in WM processes. Alpha/beta bursting decreased during stimuli encoding and increased during the delay, while gamma bursting was elevated during encoding and decreased during the delay. Deviations in bursting patterns were associated with WM errors and clinical symptoms. We conclude that dysfunctional alpha/beta and gamma burst dynamics within the frontoparietal region underlie both intra-individual WM performance and WM symptom fluctuations in adolescents with ADHD. Such burst dynamics reflect a novel target and biomarker for WM-related treatment development.

neuroscience↗