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Updated: Feb 1, 2026

Author Spotlight: Exploring the Link Between Time Perception of Visual Stimuli and Reading Skills
Published on: January 19, 2024
[I Am Seeing a Human!: The Perception of an External Visual Stimulus Where None Exists]
1Department of Radiology, School of Medicine, University of Occupational and Environmental Health.
Abstract:
A visual hallucination (VH) is "the perception of an external visual stimulus where none exists". It frequently occurs in Lewy body disease (LBD): Parkinson's disease and dementia with Lewy bodies. Although the exact pathogenesis of VH in patients with LBD is not clearly understood, many neuroimaging studies (structure MRI: brain volume, functional MRI, positron emission tomography, and single photon emission computerized tomography) have reported reduced gray matter volume, altered activation, and reduced metabolism in the dorsal and ventral visual pathways. The results obtained from the neuroimaging studies suggest the presence of aberrant visual information processing.
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