Open AccessFunctional Brain Connectivity Patterns Associated with Visual Hallucinations in Dementia with Lewy Bodies
Author(s) -
Stefania Pezzoli,
Matteo De Marco,
Giovanni Zorzi,
Annachiara Cagnin,
Annalena Venneri
Publication year - 2021
Publication title -
journal of alzheimer's disease reports
Language(s) - English
Resource type - Journals
ISSN - 2542-4823
DOI - 10.3233/adr-200288
Subject(s) - dementia with lewy bodies , neuroscience , visual hallucination , resting state fmri , functional connectivity , default mode network , psychology , dementia , superior parietal lobule , putamen , medicine , cognition , psychiatry , pathology , disease
Background: The presence of recurrent, complex visual hallucinations (VH) is among the core clinical features of dementia with Lewy bodies (DLB). It has been proposed that VH arise from a disrupted organization of functional brain networks. However, studies are still limited, especially investigating the resting-state functional brain features underpinning VH in patients with dementia. Objective: The aim of the present pilot study was to investigate whether there were any alterations in functional connectivity associated with VH in DLB. Methods: Seed-based analyses and independent component analysis (ICA) of resting-state fMRI scans were carried out to explore differences in functional connectivity between DLB patients with and without VH. Results: Seed-based analyses reported decreased connectivity of the lateral geniculate nucleus, the superior parietal lobule and the putamen with the medial frontal gyrus in DLB patients with VH. Visual areas showed a pattern of both decreased and increased functional connectivity. ICA revealed between-group differences in the default mode network (DMN). Conclusion: Functional connectivity analyses suggest dysfunctional top-down and bottom-up processes and DMN-related alterations in DLB patients with VH. This impairment might foster the generation of false visual images that are misinterpreted, ultimately resulting in VH.