title: Detecting cognitive changes in preclinical Alzheimer's disease: A review of its feasibility.
abstract: Significant progress has been made in characterizing the biological changes occurring in preclinical Alzheimer's disease (AD). Cognitive dysfunction has been viewed, however, as a late-stage phenomenon, despite increasing evidence that changes may be detected in the decades preceding dementia. In the absence of comprehensive evidence-based guidelines for preclinical cognitive assessment, longitudinal cohort and neuroimaging studies have been reviewed to determine the temporal order and brain biomarker correlates of specific cognitive functions. Episodic memory decline was observed to be the most salient cognitive function, correlating with high levels of amyloid deposition and hypoconnectivity across large-scale brain networks. Prospective studies point to early decline in both episodic and semantic memory processing as well as executive functions in the predementia period. The cognitive tests have, however, been principally those used to diagnose dementia. New procedures are required which target more finely the medial temporal lobe subregions first affected by clinically silent AD pathology.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U1061 Neuropsychiatrie, Montpellier, France; Faculty of Medicine, University of Montpellier, Montpellier, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Mortamais
authors.affiliation: Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK.
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Ash
authors.affiliation: Metis Cognition Ltd, Kilmington Common, UK; Alzheimer Center VUmc, Amsterdam, the Netherlands.
authors.forename: John
authors.initials: J
authors.lastname: Harrison
authors.affiliation: Neurology and Biomedical Engineering, Oregon Health and Science University, Portand, OR, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Kaye
authors.affiliation: Department of Neurology Memory and Ageing Centre, University of California at San Francisco, San Francisco, CA, USA.
authors.forename: Joel
authors.initials: J
authors.lastname: Kramer
authors.affiliation: Department of Neurology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Randolph
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U1061 Neuropsychiatrie, Montpellier, France.
authors.forename: Carine
authors.initials: C
authors.lastname: Pose
authors.affiliation: Clinical Research, Neuroscience and General Medicine, Eisai Inc, Woodcliff Lake, NJ, USA.
authors.forename: Bruce
authors.initials: B
authors.lastname: Albala
authors.affiliation: Clinical Research, Neurosciences, Janssen, South San Francisco, CA, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Ropacki
authors.affiliation: Centre for Dementia Prevention, University of Edinburgh, Edinburgh, UK.
authors.forename: Craig W
authors.initials: CW
authors.lastname: Ritchie
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U1061 Neuropsychiatrie, Montpellier, France; Faculty of Medicine, University of Montpellier, Montpellier, France; Centre for Dementia Prevention, University of Edinburgh, Edinburgh, UK. Electronic address: karen.ritchie@inserm.fr.
authors.forename: Karen
authors.initials: K
authors.lastname: Ritchie
mesh_terms: D000544:Alzheimer Disease / Q000175:diagnosis* / Q000523:psychology*; D003071:Cognition; D006801:Humans; D009483:Neuropsychological Tests; D062706:Prodromal Symptoms
keywords: Alzheimer's disease; Cognition; Diagnosis; Neuropsychology; Preclinical markers