This study examined the coupling between visual information and body sway in patients with Parkinson's disease (PD) compared with healthy controls. Postural control performance was compared between 14 patients with PD (age: 69.6 ± 8.8 years - stages 1-3 of the Hoehn and Yahr scale) and 14 healthy control participants (age: 68.6 ± 3.0 years). Participants stood upright in a moving room that remained motionless or continuously oscillated in the anterior-posterior direction. Ten trials were performed in the following conditions: no movement of the room (1 trial) and with the room moving at frequencies of 0.1, 0.17, and 0.5 Hz (3 trials each frequency). Body sway and moving room displacement were recorded. The results indicated that patients with PD displayed larger body sway magnitude in the stationary room condition. Body sway of patients with PD was induced by visual manipulation in all three visual stimulus frequencies, but body sway of patients with PD was less coherent compared to that of the control participants. However, no difference was observed in the visual-body sway coupling structure. These results indicate that patients with PD can unconsciously couple body sway to visual information in order to control postural sway in a similar manner to healthy participants with intact visual-motor coupling for posture control. However, this coupling is marked by greater variability, indicating that people with PD have a motor system with greater inherent noise leading to a more varied behavior.

No abstract

Background Parkinson’s disease (PD) leads to several changes in motor control, many of them related to informational or cognitive overload. The aim of this study was to investigate the influence of knowledge and intention on the postural control performance and on the coupling between visual information and body sway in people with and without PD standing upright. Methods Participants were 21 people with PD (62.1 ± 7.2 years), stages 1 and 2 (Hoehn & Yahr scale), under dopaminergic medication, and 21 people in the control group (62.3 ± 7.1 years). Participants stood upright inside a moving room, performing seven trials of 60 s. In the first trial, the room remained motionless. In the others, the room oscillated at 0.2 Hz in the anterior-posterior direction: in the first block of three trials, the participants were not informed about the visual manipulation; in the second block of three trials, participants were informed about the room movement and asked to resist the visual influence. An OPTOTRAK system recorded the moving room displacement and the participants’ sway. The variables mean sway amplitude (MSA), coherence and gain were calculated. Results With no visual manipulation, no difference occurred between groups for MSA. Under visual manipulation conditions, people with PD presented higher MSA than control, and both groups reduced the sway magnitude in the resisting condition. Control group reduced sway magnitude by 6.1%, while PD group reduced by 11.5%. No difference was found between groups and between conditions for the coupling strength (coherence). For the coupling structure (gain), there was no group difference, but both groups showed reduced gain in the resisting condition. Control group reduced gain by 12.0%, while PD group reduced by 9.3%. Conclusions People with PD, under visual manipulation, were more influenced than controls, but they presented the same coupling structure between visual information and body sway as controls. People in early stages of PD are able to intentionally alter the influence of visual information.

A prática esportiva melhora a qualidade de vida de pessoas com diferentes características, mas ainda não há informações sobre o impacto do esporte na qualidade de vida de pessoas com deficiência visual. O objetivo deste estudo foi identificar a percepção da qualidade de vida de atletas cegos de futebol de cinco e de goalball e compará-la com a qualidade de vida percebida de pessoas com deficiência visual fisicamente inativas. Trinta e sete homens com deficiência visual, separados em três grupos: 12 atletas de futebol de cinco (idade: M = 27,3 anos, DP = 10,2), 13 atletas de goalball (idade: M = 30,3 anos, DP = 7,0) e 12 pessoas fisicamente inativas (idade: M = 25,3 anos, DP = 2,3), responderam ao questionário WHOQOL-Bref. Atletas com deficiência visual obtiveram maior pontuação na Qualidade de Vida Global e Saúde Geral e em todos os domínios do WHOQOL-Bref do que pessoas fisicamente inativas. Não houve diferença entre a qualidade de vida percebida dos atletas de futebol e de goalball. Portanto, a despeito do tipo de esporte, sua prática está relacionada a uma melhor qualidade de vida de pessoas com deficiência visual.Palavras-chave: Cego. Futebol de Cegos. Futebol de Cinco. Goalball. WHOQOL-Bref.AbstractSports practice improves quality of life of people with different characteristics, but there is still no information about the impact of sport on quality of life among people with visual disorder. The aim of this study was to identify the perceived quality of life of blind football and goalball athletes and to compare it to perceived quality of life of physically inactive people with visual disorder. Thirty seven men with visual disorder, separated into three groups: 12 blind football athletes (age: M = 27.3 years, SD = 10.2), 13 goalball athletes (age: M = 30.3 years, SD = 7.0) and 12 physically inactive people (age: M = 25.3 years, SD = 2.3), answered the WHOQOL-Bref questionnaire. Athletes with visual disorder obtained a higher score in the Overall Quality of Live and General Health and in all domains of the WHOQOL-Bref than physically inactive people. There was no difference between the perceived quality of life of football and goalball athletes. Therefore, despite the type of sport, its practice is related to a better quality of life of people with visual disorder.Keywords: Blind. Blind Football. Football Five-a-side. Goalball. WHOQOL-Bref.