| Title: |
Functional and structural brain network correlates of visual hallucinations in Lewy body dementia |
| Authors: |
Mehraram, Ramtin; Peraza, Luis R.; Murphy, Nicholas R.E.; Cromarty, Ruth A.; Graziadio, Sara; O'brien, John T.; Killen, Alison; Colloby, Sean J.; Firbank, Michael; Su, Li; Collerton, Daniel; Taylor, John Paul; Kaiser, Marcus |
| Publisher Information: |
Oxford University Press |
| Publication Year: |
2022 |
| Collection: |
University of Nottingham: Repository@Nottingham |
| Description: |
Visual hallucinations are a common feature of Lewy body dementia. Previous studies have shown that visual hallucinations are highly specific in differentiating Lewy body dementia from Alzheimer's disease dementia and Alzheimer-Lewy body mixed pathology cases. Computational models propose that impairment of visual and attentional networks is aetiologically key to the manifestation of visual hallucinations symptomatology. However, there is still a lack of experimental evidence on functional and structural brain network abnormalities associated with visual hallucinations in Lewy body dementia. We used EEG source localization and network based statistics to assess differential topographical patterns in Lewy body dementia between 25 participants with visual hallucinations and 17 participants without hallucinations. Diffusion tensor imaging was used to assess structural connectivity between thalamus, basal forebrain and cortical regions belonging to the functionally affected network component in the hallucinating group, as assessed with network based statistics. The number of white matter streamlines within the cortex and between subcortical and cortical regions was compared between hallucinating and not hallucinating groups and correlated with average EEG source connectivity of the affected subnetwork. Moreover, modular organization of the EEG source network was obtained, compared between groups and tested for correlation with structural connectivity. Network analysis showed that compared to non-hallucinating patients, those with hallucinations feature consistent weakened connectivity within the visual ventral network, and between this network and default mode and ventral attentional networks, but not between or within attentional networks. The occipital lobe was the most functionally disconnected region. Structural analysis yielded significantly affected white matter streamlines connecting the cortical regions to the nucleus basalis of Meynert and the thalamus in hallucinating compared to not hallucinating patients. ... |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
https://nottingham-repository.worktribe.com/output/49280648; Brain; Volume 145; Issue 6; Pagination 2190-2205 |
| DOI: |
10.1093/brain/awac094 |
| Availability: |
https://doi.org/10.1093/brain/awac094; https://nottingham-repository.worktribe.com/file/49280648/1/Mehraram2022; https://nottingham-repository.worktribe.com/output/49280648 |
| Rights: |
openAccess ; https://creativecommons.org/licenses/by/4.0/ |
| Accession Number: |
edsbas.591E22E |
| Database: |
BASE |