Lower cognitive control network connectivity in stroke participants with depressive features

Area of Science:

• Neuroscience
• Neurology
• Psychiatry

Background:

• Post-stroke depression affects one-third of patients, with mechanisms poorly understood.
• Previous research linked depression to left dorsolateral prefrontal cortex (DLPFC) lesions, but depression is a network disorder.
• Cognitive control network (CCN) resting-state connectivity, seeded by DLPFC, is reduced in non-stroke depression.

Purpose of the Study:

• To investigate the association between post-stroke depressive features and CCN resting-state connectivity.
• To explore if DLPFC connectivity changes are present in post-stroke depression, independent of lesion location.

Main Methods:

• Analyzed resting-state functional connectivity of the DLPFC in 64 stroke participants.
• Assessed depressive features using the Patient Health Questionnaire (PHQ-9) at 3 months post-stroke.
• Compared connectivity between depressed and non-depressed groups and performed regression analysis controlling for clinical factors.

Main Results:

• Post-stroke depression was associated with lower connectivity between the left DLPFC and the right supramarginal gyrus (SMG).
• These connectivity changes were observed in both group comparisons and regression analyses.
• Neither the seed region nor the affected network overlapped with stroke lesions.

Conclusions:

• Post-stroke depression is linked to disruptions in the cognitive control network (CCN), specifically reduced left DLPFC-right SMG connectivity.
• These network alterations can occur even without direct lesions in the DLPFC, highlighting the role of large-scale network dysfunction.