title: Heterogeneous pathologies associated with dementia in Parkinsonism share a prion-like spreading mechanism.
abstract: Cognitive alterations accompany or follow motor disorders in subjects with Parkinsonism. The canonical phenotypeof the Parkinson's disease Dementia (PD-D) or Lewy Body Dementia (LBD) includes deficit of attention, executiveand visuospatial functions, and presents often with apathy, hallucinations, delusions, excessive daytime sleepiness,or sleep disorders. However, the clinical expression may overlap with other neurodegenerative diseases associatedwith cognitive disorders. Thus, while clinicians rely on phenomenological patterns to infer the disease causing thecognitive impairment, the inference is weakened by the heterogeneous clinical expression of the disease. In addition,recent post-mortem studies seem to undermine the supposed pathology-phenotype coherence, making it moreand more unreliable the diagnosis based on symptoms. The lack of coherence between phenotype and pathologymay support the speculation about a common mechanism underlying the progression of the disease. While it is verylikely that a distinct, specific causal event determines the disease itself, the progression might well follow commonpatterns. A number of observations suggest that progressive diseases, which cause cognitive impairment, share aprion-like mechanism. A seeding process is supposed to account for the spreading of the lesion.
authors.forename: Serena
authors.initials: S
authors.lastname: Candela
authors.forename: Franco
authors.initials: F
authors.lastname: Giubilei
authors.affiliation: Dipartimento di Neuroscienze, Salute Mentale ed Organi di Senso (NESMOS), Università di Roma "La Sapienza". Email: francesco.orzi@uniroma1.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Orzi