Influence of visual feedback sampling on obstacle crossing behavior in people with Parkinson's disease.
The purpose of the current study was to investigate the role of visual information on gait control in people with Parkinson's disease as they crossed over obstacles. Twelve healthy individuals, and 12 patients with mild to moderate Parkinson's disease, walked at their preferred speeds along a walkway and stepped over obstacles of varying heights (ankle height or half-knee height), under three visual sampling conditions: dynamic (normal lighting), static (static visual samples, similar to stroboscopic lighting), and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. In the static visual sampling condition only, the patients with Parkinson's disease made contact with the obstacle more often than did the control subjects. In the successful trials, the patients increased their crossing step width in the static visual sampling condition as compared to the dynamic and voluntary visual sampling conditions; the control group maintained the same step width for all visual sampling conditions. The patients showed lower horizontal mean velocity values during obstacle crossing than did the controls. The patients with Parkinson's disease were more dependent on optic flow information for successful task and postural stability than were the control subjects. Bradykinesia influenced obstacle crossing in the patients with Parkinson's disease.
UNESP - São Paulo State University at Rio Claro, Av 24-A, 1515 Rio Claro, SP 13506-900, Brazil. vitoriorodrigo@gmail.com
Rodrigo
R
Vitório
Ellen
E
Lirani-Silva
Fabio Augusto
FA
Barbieri
Vivian
V
Raile
Florindo
F
Stella
Lilian Teresa Bucken
LT
Gobbi
D000368:Aged; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D056228:Feedback, Sensory / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*
Gait; Motor control; Optic flow; Parkinson's disease