Article

Learning and consolidation of visuo-motor adaptation in Parkinson's disease

Department of Physiology & Pharmacology, CUNY Medical School, New York, NY 100031, USA.
Parkinsonism & Related Disorders (Impact Factor: 4.13). 05/2008; 15(1):6-11. DOI: 10.1016/j.parkreldis.2008.02.012
Source: PubMed

ABSTRACT We have previously shown in normal subjects that motor adaptation to imposed visual rotation is significantly enhanced when tested few days later. This occurs through a process of sleep-dependent memory consolidation. Here we ascertained whether patients with Parkinson's disease (PD) learn, improve, and retain new motor skills in the same way as normal subjects. We tested 16 patients in early stages of PD and 21 control subjects over two days. All subjects performed reaching movements on a digitizing tablet. Vision of the limb was precluded with an opaque screen; hand paths were shown on the screen with the targets' position. Unbeknownst to the subjects, the hand path on the screen was rotated by 30 degrees . In experiment 1, patients taking dopaminergic treatment and controls adapted to rotation with targets appearing in an unpredictable order. In experiment 2, drug-naïve patients and controls adapted to rotation in a less challenging task where target's appearance was predictable. Patients and controls made similar movements and adapted to rotation in the same way. However, when tested again over the following days, controls' performance significantly improved compared to training, while patients' performance did not. This lack of consolidation, which is present in the early stages of the disease and is independent from therapy, may be due to abnormal homeostatic processes that occur during sleep.

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Available from: Marco Bove, Jun 02, 2015
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    ABSTRACT: Background Sleep disturbances are among the most common non-motor symptoms of Parkinson’s disease (PD), greatly interfering with daily activities and diminishing life quality. Pharmacological treatments have not been satisfactory because of side effects and interactions with anti-parkinsonian drugs. While studies have shown that regular exercise improves sleep quality in normal aging, there is no definitive evidence in PD. Methods In a retrospective study, we determined whether an intense physical and multidisciplinary exercise program improves sleep quality in a large group of patients with PD. We analyzed the scores of PD Sleep Scale (PDSS), which was administered twice, 28 days apart, to two groups of patients with PD of comparable age, gender, disease duration and pharmacological treatment. The control group (49 patients) did not receive rehabilitation, The treated group (89 patients) underwent a 28-day multidisciplinary intensive rehabilitation program (three one-hour daily sessions comprising cardiovascular warm-up, relaxation, muscle-stretching, balance and gait training, occupational therapy to improve daily living activities). Results At enrolment, control and treated groups had similar UPDRS and PDSS scores. At re-test, 28 days later, UPDRS and total PDSS scores improved in the treated (p < 0.0001) but not in the control group. In particular, the treated group showed significant improvement in PDSS scores for sleep quality, motor symptoms and daytime somnolence. The control group did not show improvement for any item. Conclusions These results suggest that multidisciplinary intensive rehabilitation treatment may have a positive impact on many aspects of sleep in PD. Keywords: PDSS; Rehabilitation; Plasticity; Sleep quality