title: Subtle visuomotor difficulties in preclinical Alzheimer's disease.
abstract: Individuals with preclinical Alzheimer's disease (Pre-AD) present nonimpaired cognition, as measured by standard neuropsychological tests. However, detecting subtle difficulties in cognitive functions may be necessary for an early diagnosis and intervention.
  
  
  
  A new computer-based visuomotor coordination task (VMC) was developed to investigate the possible presence of early visuomotor difficulties in Pre-AD individuals. Associations between VMC task performance and AD biomarkers were studied. The influence of ApoE status on participants' performance was addressed, as well as the relationship between performance and subjective cognitive decline (SCD).
  
  
  
  Sixty-six cognitively normal (CN) elders (19 Pre-AD and 47 control participants [CTR]) and 15 patients with AD performed the VMC task, which consisted in executing visually guided goal-directed movements that required the coordination of the visual and motor systems. All participants underwent ApoE analysis and lumbar puncture. CN participants also completed an extensive standard neuropsychological battery.
  
  
  
  Despite presenting normal cognition in standard tests, Pre-AD participants exhibited higher response times (RTs) to complete the VMC task than CTR (p < .01). Besides, patients with AD showed higher RTs than CTR (p < .001) and Pre-AD (p < .05), and more errors than CTR (p < .005). RTs in ApoE4 carriers were higher than that observed in ApoE4 noncarriers (p < .01). In CN individuals, RTs were related to amyloid β-protein 42 (AB42) biomarker (p < .01) and informant-rated SCD (p < .01).
  
  
  
  The VMC task is able to discriminate Pre-AD from CTR individuals. Moreover, VMC results are associated with AB42 levels in CN individuals, suggesting that visuomotor dysfunction may be a sensitive marker of Pre-AD.
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Mollica
authors.affiliation: Experimental Psychology and Brain Disorders Laboratory, Sant Joan de Deu Healthcare Park, Sant Joan de Deu Hospital, Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Navarra
authors.affiliation: Experimental Psychology and Brain Disorders Laboratory, Sant Joan de Deu Healthcare Park, Sant Joan de Deu Hospital, Barcelona, Spain.|Biomedical Network Research Centre on Mental Health (CIBERSAM), Madrid, Spain.|Institute for Brain, Cognition and Behaviour (IR3C), Department of Basic Psychology, Faculty of Psychology, University of Barcelona, Barcelona, Spain.
authors.forename: Irune
authors.initials: I
authors.lastname: Fernández-Prieto
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.
authors.forename: Jaume
authors.initials: J
authors.lastname: Olives
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.
authors.forename: Adrià
authors.initials: A
authors.lastname: Tort
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.
authors.forename: Natalia
authors.initials: N
authors.lastname: Valech
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.
authors.forename: Nina
authors.initials: N
authors.lastname: Coll-Padrós
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.|August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Molinuevo
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain.|August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Rami
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000150:complications* / Q000235:genetics / Q000523:psychology; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D001057:Apolipoproteins E / Q000235:genetics; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000134:cerebrospinal fluid; D011581:Psychological Tests; D011596:Psychomotor Disorders / Q000175:diagnosis / Q000209:etiology*; D011930:Reaction Time / Q000502:physiology; D013223:Statistics as Topic
chemical_list: D016229:Amyloid beta-Peptides; D001057:Apolipoproteins E; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)
keywords: Alzheimer disease; ApoE; Visual Motor Coordination; biomarkers; task performance