Findings of PTSD-specific deficits in default mode network strength following a mild experimental stressor.
NPP Digit Psychiatry Neurosci
; 2(1): 9, 2024.
Article
en En
| MEDLINE
| ID: mdl-38919723
ABSTRACT
Reductions in default mode (DMN) connectivity strength have been reported in posttraumatic stress disorder (PTSD). However, the specificity of DMN connectivity deficits in PTSD compared to major depressive disorder (MDD), and the sensitivity of these alterations to acute stressors are not yet known. 52 participants with a primary diagnosis of PTSD (n = 28) or MDD (n = 24) completed resting-state functional magnetic resonance imaging immediately before and after a mild affective stressor. A 2 × 2 design was conducted to determine the effects of group, stress, and group*stress on DMN connectivity strength. Exploratory analyses were completed to identify the brain region(s) underlying the DMN alterations. There was significant group*stress interaction (p = 0.03), reflecting stress-induced reduction in DMN strength in PTSD (p = 0.02), but not MDD (p = 0.50). Nodal exploration of connectivity strength in the DMN identified regions of the ventromedial prefrontal cortex and the precuneus potentially contributing to DMN connectivity deficits. The findings indicate the possibility of distinct, disease-specific, patterns of connectivity strength reduction in the DMN in PTSD, especially following an experimental stressor. The identified dynamic shift in functional connectivity, which was perhaps induced by the stressor task, underscores the potential utility of the DMN connectivity and raises the question whether these disruptions may be inversely affected by antidepressants known to treat both MDD and PTSD psychopathology.
To study any differences between PTSD and depression in the way the brain talks with itself in its default mode when not doing any particular thing, we did MRI brain scans with 52 people with Depression, but only some had PTSD. We found that mild emotional stress may briefly reduce default mode strength in PTSD, but not in depression. This might help researchers better understand the impact of stress and trauma on the brain.
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Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
NPP Digit Psychiatry Neurosci
Año:
2024
Tipo del documento:
Article
Pais de publicación:
Suiza