title: Motor Sequence Learning and Consolidation in Unilateral De Novo Patients with Parkinson's Disease.
abstract: Previous research investigating motor sequence learning (MSL) and consolidation in patients with Parkinson's disease (PD) has predominantly included heterogeneous participant samples with early and advanced disease stages; thus, little is known about the onset of potential behavioral impairments. We employed a multisession MSL paradigm to investigate whether behavioral deficits in learning and consolidation appear immediately after or prior to the detection of clinical symptoms in the tested (left) hand. Specifically, our patient sample was limited to recently diagnosed patients with pure unilateral PD. The left hand symptomatic (LH-S) patients provided an assessment of performance following the onset of clinical symptoms in the tested hand. Conversely, right hand affected (left hand asymptomatic, LH-A) patients served to investigate whether MSL impairments appear before symptoms in the tested hand. LH-S patients demonstrated impaired learning during the initial training session and both LH-S and LH-A patients demonstrated decreased performance compared to controls during the next-day retest. Critically, the impairments in later learning stages in the LH-A patients were evident even before the appearance of traditional clinical symptoms in the tested hand. Results may be explained by the progression of disease-related alterations in relevant corticostriatal networks.
authors.affiliation: Department of Neurobiology and Neurology, Key Laboratory of Ministry of Education on Neurodegenerative Disorders, Beijing Key Laboratory on Parkinson's Disease, Xuanwu Hospital of Capital Medical University, Beijing, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Dan
authors.affiliation: Functional Neuroimaging Unit, Department of Psychology, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Bradley R
authors.initials: BR
authors.lastname: King
authors.affiliation: Functional Neuroimaging Unit, Department of Psychology, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Julien
authors.initials: J
authors.lastname: Doyon
authors.affiliation: Department of Neurobiology and Neurology, Key Laboratory of Ministry of Education on Neurodegenerative Disorders, Beijing Key Laboratory on Parkinson's Disease, Xuanwu Hospital of Capital Medical University, Beijing, China; Parkinson's Disease Center of Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Piu
authors.initials: P
authors.lastname: Chan
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006225:Hand; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D000069077:Memory Consolidation / Q000502:physiology; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology*; D011597:Psychomotor Performance / Q000502:physiology*