Preclinical Polymodal Hallucinations for 13 Years before Dementia with Lewy Bodies
Behavioural Neurology April 27, 2014 C. Abbate, P. Trimarchi, S. Inglese et al.
A patient with dementia with Lewy bodies (DLB) experienced long-lasting complex hallucinations before developing dementia. Over four years, detailed assessments at the predementia stage revealed hypnagogic and hypnopompic hallucinations, which helped distinguish DLB from Charles Bonnet syndrome. Neuropsychological testing showed a multiple-domain mild cognitive impairment without amnesia, including prefrontal executive, visuoperceptual, and visuospatial deficits, plus simultanagnosia—a finding not previously reported in MCI-DLB. These results extend the prognostic value of hallucinations to preclinical DLB, refine the MCI-DLB concept, identify simultanagnosia as a possible early cognitive marker, and support the idea that early hallucinations in DLB may reflect a narcolepsy-like REM-sleep disorder.