title: Spatial Navigation in Preclinical Alzheimer's Disease.
abstract: Although several previous studies have demonstrated navigational deficits in early-stage symptomatic Alzheimer's disease (AD), navigational abilities in preclinical AD have not been examined. The present investigation examined the effects of preclinical AD and early-stage symptomatic AD on spatial navigation performance. Performance on tasks of wayfinding and route learning in a virtual reality environment were examined. Comparisons were made across the following three groups: Clinically normal without preclinical AD (n = 42), clinically normal with preclinical AD (n = 13), and early-stage symptomatic AD (n = 16) groups. Preclinical AD was defined based on cerebrospinal fluid Aβ42 levels below 500 pg/ml. Preclinical AD was associated with deficits in the use of a wayfinding strategy, but not a route learning strategy. Moreover, post-hoc analyses indicated that wayfinding performance had moderate sensitivity and specificity. Results also confirmed early-stage symptomatic AD-related deficits in the use of both wayfinding and route learning strategies. The results of this study suggest that aspects of spatial navigation may be particularly sensitive at detecting the earliest cognitive deficits of AD.
authors.affiliation: Department of Psychology, Washington University in St. Louis, St. Louis, MO, USA.
authors.forename: Samantha L
authors.initials: SL
authors.lastname: Allison
authors.affiliation: Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA.|Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO, USA.|Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA.
authors.forename: Anne M
authors.initials: AM
authors.lastname: Fagan
authors.affiliation: Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA.|Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA.
authors.forename: John C
authors.initials: JC
authors.lastname: Morris
authors.affiliation: Department of Psychology, Washington University in St. Louis, St. Louis, MO, USA.|Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA.|Department of Radiology, Washington University in St. Louis, St. Louis, MO, USA.
authors.forename: Denise
authors.initials: D
authors.lastname: Head
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000523:psychology*; D015415:Biomarkers / Q000134:cerebrospinal fluid; D004522:Educational Status; D005260:Female; D006801:Humans; D007858:Learning; D008297:Male; D009483:Neuropsychological Tests; D062706:Prodromal Symptoms; D011597:Psychomotor Performance; D012372:ROC Curve; D065854:Spatial Navigation; D014584:User-Computer Interface; D016875:tau Proteins / Q000134:cerebrospinal fluid
chemical_list: D015415:Biomarkers; C054369:MAPT protein, human; D016875:tau Proteins
keywords: Aging; allocentric; amyloid; caudate nucleus; egocentric; hippocampus