Dissociated large-scale functional connectivity networks of the precuneus in medication-naïve first-episode depression.
An imbalance in neural activity within large-scale networks appears to be an important pathophysiological aspect of depression. Yet, there is little consensus regarding the abnormality within the default mode network (DMN) in major depressive disorder (MDD). In the present study, 16 first-episode, medication-naïve patients with MDD and 16 matched healthy controls underwent functional magnetic resonance imaging (fMRI) at rest. With the precuneus (a central node of the DMN) as a seed region, functional connectivity (FC) was measured across the entire brain. The association between the FC of the precuneus and overall symptom severity was assessed using the Hamilton Depression Rating Scale. Patients with MDD exhibited a more negative relationship between the precuneus and the non-DMN regions, including the sensory processing regions (fusiform gyrus, postcentral gyrus) and the secondary motor cortex (supplementary motor area and precentral gyrus). Moreover, greater severity of depression was associated with greater anti-correlation between the precuneus and the temporo-parietal junction as well as stronger positive connectivity between the precuneus and the dorsomedial prefrontal cortex. These results indicate that dissociated large-scale networks of the precuneus may contribute to the clinical expression of depression in MDD.
['Peng|Daihui|D|', 'Liddle|Elizabeth B|EB|', 'Iwabuchi|Sarina J|SJ|', 'Zhang|Chen|C|', 'Wu|Zhiguo|Z|', 'Liu|Jun|J|', 'Jiang|Kaida|K|', 'Xu|Lin|L|', 'Liddle|Peter F|PF|', 'Palaniyappan|Lena|L|', 'Fang|Yiru|Y|']
D000328:Adult D001921:Brain D003865:Depressive Disorder, Major D005260:Female D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D009415:Nerve Net D010296:Parietal Lobe D012720:Severity of Illness Index
Functional connectivity network Precuneus Depression Functional magnetic resonance imaging Resting state