Frontoparietal function in young people with dysthymic disorder (DSM-5: Persistent depressive disorder) during...

Area of Science:

• Neuroscience
• Developmental Psychology
• Psychiatry

Background:

• Dysthymic disorder (DD) is a persistent mood disorder and a risk factor for major depressive disorder (MDD).
• Both DD and MDD are linked to executive function deficits, particularly in working memory and attention.
• Brain network alterations in youth with DD are poorly understood.

Purpose of the Study:

• To investigate brain function associated with spatial working memory in children and adolescents with DD.
• To compare brain activity in DD patients with age-, gender-, and IQ-matched typically developing controls using fMRI.

Main Methods:

• Nineteen medication-naïve male patients with DD and 16 typically developing boys underwent fMRI.
• Participants completed two spatial working memory tasks: mental rotation and delay-match to sample (DMTS).

Main Results:

• The DD group exhibited reduced activation in left prefrontal cortex (PFC) regions during mental rotation compared to controls.
• Reduced activation was also observed in medial frontal regions, including the dorsomedial PFC, anterior cingulate cortex, and frontal pole.
• During the DMTS task, patients showed increased activation in the right precuneus and posterior cingulate cortex.

Conclusions:

• Findings in youth with DD complement adult MDD studies, highlighting altered left PFC function during working memory.
• Altered function of cortical midline structures was identified in young DD patients.
• Results suggest the pathophysiology of depressive disorders extends to DD, showing continuity across the lifespan.