Visual cortical excitability in dementia with Lewy bodies
The British Journal of Psychiatry
The Royal College of Psychiatrists
MetadataShow full item record
Taylor, J., Firbank, M., & O'Brien, J. (2015). Visual cortical excitability in dementia with Lewy bodies. The British Journal of Psychiatry https://doi.org/10.1192/bjp.bp.114.152736
Alterations in the visual system may underlie visual hallucinations in dementia with Lewy bodies (DLB). However, cortical excitability as measured by transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) activation of lower visual areas (V1-3) to visual stimuli appear normal in DLB. We explored the relationship between TMS-determined phosphene threshold and fMRI-related visual activation and found a positive relationship between the two in controls but a negative one in DLB. This double dissociation suggests a loss of inhibition in the visual system in DLB, which may predispose individuals to visual dysfunction and visual hallucinations.
The research was funded by an Intermediate Clinical Fellowship to J.-P.T. (WT088441MA) and also supported by the National Institute for Health Research (NIHR) Newcastle Biomedical Research Unit based at Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.
External DOI: https://doi.org/10.1192/bjp.bp.114.152736
This record's URL: https://www.repository.cam.ac.uk/handle/1810/252699
Attribution 2.0 UK: England & Wales
Licence URL: http://creativecommons.org/licenses/by/2.0/uk/
Recommended or similar items
The following licence files are associated with this item: