Relation between patterns of intrinsic network connectivity, cognitive functioning, and symptom presentation in trauma-exposed patients with major depressive disorder.

Melissa Parlar,Ruth A Lanius,Geoffrey B Hall,Paul A Frewen,Maria Densmore,Margaret C Mckinnon

doi:10.1002/brb3.664

Melissa Parlar, Ruth A Lanius + Show 4 more

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https://doi.org/10.1002/brb3.664

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Journal: Brain and Behavior	Publication Date: Mar 31, 2017
Citations: 13	License type: CC BY 4.0

Affiliation: McMaster University, Western University

Abstract

ObjectiveThe present study investigated resting fMRI connectivity within the default mode (DMN), salience (SN), and central executive (CEN) networks in relation to neurocognitive performance and symptom severity in trauma‐exposed patients with major depressive disorder (MDD).MethodGroup independent component analysis was conducted among patients with MDD (n = 21), examining DMN, SN, and CEN connectivity in relation to neurocognitive performance and symptom severity. Activation in these networks was also compared between the patient group and healthy controls (n = 20).ResultsAmong the patient group, higher levels of performance on measures of verbal memory and executive functioning were related to increased connectivity within the DMN (i.e., inferior parietal lobe; precuneus). Greater depression severity was related to reduced connectivity between the SN and a node of the DMN (i.e., posterior cingulate cortex) and higher depersonalization symptoms were related to enhanced connectivity between the SN and a node of the DMN (i.e., middle temporal gyrus). Higher symptoms of depersonalization were also associated with reduced integration of the DMN with the medial frontal gyrus. Relative to controls, patients with MDD showed greater connectivity of the ventromedial prefrontal cortex within the DMN.ConclusionIntrinsic connectivity network patterns are related to cognitive performance and symptom presentation among trauma‐exposed patients with MDD.

Highlights

In addition to its core affective components, major depressive disorder (MDD) is characterized by dysfunction in frontal-temporally mediated cognitive domains, including executive functioning (Snyder, 2012), processing speed (McDermott & Ebmeier, 2009), working memory (Gałecki et al, 2013), and recollective memory (Talarowska et al, 2010)
Patients with trauma-related disorders, including post-traumatic stress disorder (PTSD), show deficits in a similar range of cognitive domains (Cohen et al, 2013), with structural and functional brain changes observed across MDD and trauma-related disorders in regions linked to recollective memory (McKinnon, Yucel, Nazarov, & MacQueen, 2009), attention (Yucel et al, 2008), and executive functioning (Koenigs & Grafman, 2009)
Despite the increasing focus on dissociative symptoms in MDD and their relation to more severe symptoms and trauma exposure (Molina-S errano, Linotte, Amat, Souery, & Barreto, 2008; Žikić, Ćirić, & Mitković, 2009), it is unknown whether these symptoms are associated with altered network connectivity in patients with depression and a history of trauma. We investigate those core neural networks thought to be central to higher-order cognitive functioning to determine if alterations in the connectivity of intrinsic connectivity networks (ICNs) is related to neurocognitive performance and symptom presentation among trauma-exposed patients with MDD

Summary

| INTRODUCTION

In addition to its core affective components, major depressive disorder (MDD) is characterized by dysfunction in frontal-temporally mediated cognitive domains, including executive functioning (Snyder, 2012), processing speed (McDermott & Ebmeier, 2009), working memory (Gałecki et al, 2013), and recollective memory (Talarowska et al, 2010) These deficits are of significant concern as they contribute to. Despite the high prevalence of trauma exposure in depression and its negative effects on cognitive functioning and treatment outcome, no studies have examined alterations in ICNs in relation to cognitive functioning and symptom presentation, including dissociation, in this patient population This effort may assist in better understanding the neural mechanisms underlying the reduced treatment and functional outcomes observed in this population. No studies have examined the relation between these core neural networks and performance on standardized neuropsychological assessments tapping frontal-temporally mediated cognitive domains in patients with MDD and a history of trauma

| Aims of the study

| Participants

Findings

| DISCUSSION