Compensatory postural adjustments in na oculus virtual reality environment and the risk of falling in Alzheimer’s disease

• Autor(a) principal: Gago, Miguel F.
• Data de Publicação: 2016
• Outros Autores: Yelshyna, Darya, Bicho, Estela, Silva, Hélder, Rocha, Luís Alexandre Machado, Rodrigues, Maria Lurdes, Sousa, Nuno
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/45110
• topic: Alzheimer’s disease; Falls; Compensatory postural adjustments; Oculus virtual reality; Time-frequency distribution; Inertia measurement units; Science & Technology

Background/Aims Alzheimer's disease (AD) patients have an impaired ability to quickly reweight central sensory dependence in response to unexpected body perturbations. Herein, we aim to study provoked compensatory postural adjustments (CPAs) in a conflicting sensory paradigm with unpredictable visual displacements using virtual reality goggles. Methods We used kinematic time-frequency analyses of two frequency bands: a low-frequency band (LB; 0.3-1.5 Hz; mechanical strategy) and a high-frequency band (HB; 1.5-3.5 Hz; cognitive strategy). We enrolled 19 healthy subjects (controls) and 21 AD patients, divided according to their previous history of falls. Results The AD faller group presented higher-power LB CPAs, reflecting their worse inherent postural stability. The AD patients had a time lag in their HB CPA reaction. Conclusion The slower reaction by CPA in AD may be a reflection of different cognitive resources including body schema self-perception, visual motion, depth perception, or a different state of fear and/or anxiety.