Distinct brain networks underlie cognitive dysfunction in Parkinson and Alzheimer diseases. Academic Article uri icon

Overview

abstract

  • OBJECTIVE: To determine whether cognitive impairment in Parkinson disease (PD) and Alzheimer disease (AD) derives from the same network pathology. METHODS: We analyzed 18F-fluorodeoxyglucose PET scans from 40 patients with AD and 40 age-matched healthy controls from the Alzheimer's Disease Neuroimaging Initiative and scanned an additional 10 patients with AD and 10 healthy controls at The Feinstein Institute for Medical Research to derive an AD-related metabolic pattern (ADRP) analogous to our previously established PD cognition-related pattern (PDCP) and PD motor-related pattern (PDRP). We computed individual subject expression values for ADRP and PDCP in 89 patients with PD and correlated summary scores for cognitive functioning with network expression. We also evaluated changes in ADRP and PDCP expression in a separate group of 15 patients with PD scanned serially over a 4-year period. RESULTS: Analysis revealed a significant AD-related metabolic topography characterized by covarying metabolic reductions in the hippocampus, parahippocampal gyrus, and parietal and temporal association regions. Expression of ADRP, but not PDCP, was elevated in both AD groups and correlated with worse cognitive summary scores. Patients with PD showed slight ADRP expression, due to topographic overlap with the network underlying PD motor-related pattern degeneration, but only their PDCP expression values increased as cognitive function and executive performance declined. Longitudinal data in PD disclosed an analogous dissociation of network expression. CONCLUSIONS: Cognitive dysfunction in PD is associated with a specific brain network that is largely spatially and functionally distinct from that seen in relation to AD.

publication date

  • October 5, 2016

Research

keywords

  • Alzheimer Disease
  • Brain
  • Cognition Disorders
  • Parkinsonian Disorders

Identity

PubMed Central ID

  • PMC5100716

Scopus Document Identifier

  • 84994102590

Digital Object Identifier (DOI)

  • 10.1212/WNL.0000000000003285

PubMed ID

  • 27708130

Additional Document Info

volume

  • 87

issue

  • 18