Vulnerability of multiple large-scale brain networks in dementia with Lewy bodies.
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ABSTRACT:
SUBMITTER: Sala A
PROVIDER: S-EPMC6917031 | biostudies-literature | 2019 Oct
REPOSITORIES: biostudies-literature
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Vulnerability of multiple large-scale brain networks in dementia with Lewy bodies.
Sala Arianna A Caminiti Silvia Paola SP Iaccarino Leonardo L Beretta Luca L Iannaccone Sandro S Magnani Giuseppe G Padovani Alessandro A Ferini-Strambi Luigi L Perani Daniela D
Human brain mapping 20190719 15
Aberrations of large-scale brain networks are found in the majority of neurodegenerative disorders. The brain connectivity alterations underlying dementia with Lewy bodies (DLB) remain, however, still elusive, with contrasting results possibly due to the pathological and clinical heterogeneity characterizing this disorder. Here, we provide a molecular assessment of brain network alterations, based on cerebral metabolic measurements as proxies of synaptic activity and density, in a large cohort o ...[more]
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Project description:The clinical phenotype of dementia with Lewy bodies (DLB) is different from Alzheimer's disease (AD), suggesting a divergence between these diseases in terms of brain network organization. To fully understand this, we studied functional networks from resting-state functional magnetic resonance imaging in cognitively matched DLB and AD patients. The DLB group demonstrated a generalized lower synchronization compared with the AD and healthy controls, and this was more severe for edges connecting distant brain regions. Global network measures were significantly different between DLB and AD. For instance, AD showed lower small-worldness than healthy controls, while DLB showed higher small-worldness (AD < controls < DLB), and this was also the case for global efficiency (DLB > controls > AD) and clustering coefficient (DLB < controls < AD). Differences were also found for nodal measures at brain regions associated with each disease. Finally, we found significant associations between network performance measures and global cognitive impairment and severity of cognitive fluctuations in DLB. These results show network divergences between DLB and AD which appear to reflect their neuropathological differences.
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