Hostname: page-component-6766d58669-7fx5l Total loading time: 0 Render date: 2026-05-23T03:13:25.928Z Has data issue: false hasContentIssue false

Default mode dysfunction underpins suicidal activity in mood disorders

Published online by Cambridge University Press:  30 May 2019

Gin S. Malhi*
Affiliation:
Academic Department of Psychiatry, Northern Sydney Local Health District, St Leonards, NSW 2065, Australia ARCHI, Sydney Medical School Northern, The University of Sydney, NSW 2006, Australia Sydney Medical School Northern, The University of Sydney, NSW 2006, Australia CADE Clinic, Royal North Shore Hospital, Northern Sydney Local Health District, St Leonards, NSW 2065, Australia
Pritha Das
Affiliation:
Academic Department of Psychiatry, Northern Sydney Local Health District, St Leonards, NSW 2065, Australia ARCHI, Sydney Medical School Northern, The University of Sydney, NSW 2006, Australia Sydney Medical School Northern, The University of Sydney, NSW 2006, Australia CADE Clinic, Royal North Shore Hospital, Northern Sydney Local Health District, St Leonards, NSW 2065, Australia
Tim Outhred
Affiliation:
Academic Department of Psychiatry, Northern Sydney Local Health District, St Leonards, NSW 2065, Australia ARCHI, Sydney Medical School Northern, The University of Sydney, NSW 2006, Australia Sydney Medical School Northern, The University of Sydney, NSW 2006, Australia CADE Clinic, Royal North Shore Hospital, Northern Sydney Local Health District, St Leonards, NSW 2065, Australia
Richard A. Bryant
Affiliation:
School of Psychology, University of New South Wales, Sydney, New South Wales, NSW 2052, Australia
Vince Calhoun
Affiliation:
The Mind Research Network, Albuquerque, NM, USA Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, NM, USA
J. John Mann
Affiliation:
Department of Psychiatry, Columbia University, New York, USA Molecular Imaging and the Neuropathology Division, New York State Psychiatric Institute, New York, USA
*
Author for correspondence: Gin S. Malhi, E-mail: gin.malhi@sydney.edu.au

Abstract

Background

Suicide is a serious and not uncommon consequence of mood disorders that occurs primarily when individuals are depressed. Understanding the neurobiology of suicidal activity (thoughts or behaviors) is likely to facilitate prevention.

Method

Seventy-nine adult depressed mood disorder patients (MDP), of which 25 had attempted suicide at least once, and 66 healthy controls (HC) participated in this study. Resting-state functional MRI was used to identify neural activity differences between suicide attempters (SA) and non-attempters (NA). Specifically, differences were examined in functional connectivity both within and between four large cognitive networks [Executive Control (ECN), Default Mode (DMN), Salience (SN), and Basal Ganglia (BGN)] and their respective associations with suicidal activity.

Results

Compared to HCs, patients had greater posterior DMN activity, but less activity in the BGN, and less low-frequency spectral power in the dorso-medial DMN. Furthermore, increased posterior DMN activity in SA was associated with recent suicidal activity, whereas NA had reduced BGN activity and less dorso-medial DMN spectral power, the latter being associated with lifelong suicidal thinking. SA also had greater activity in midline circuitry compared to both HC and NA, and the pattern of BGN and DMN co-activity differed between SA and NA.

Conclusions

DMN engagement raises the possibility that suicidal activity in mood disorder patients may be a consequence of impaired self-referential thought processing. Furthermore, differential BGN and DMN co-activation according to suicide attempt status suggests that attempting suicide perhaps alters cognitive flexibility. These insights are potentially useful for understanding the neural basis of suicide activity.

Information

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2019

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

Supplementary material: PDF

Malhi et al. supplementary material

Malhi et al. supplementary material 1

Download Malhi et al. supplementary material(PDF)
PDF 57.1 KB