Kátia Tanaka

Abstract—Patients with neurodegenerative diseases are required to use cognitive resources while maintaining postural control. The aim of this study was to investigate the effects of a frontal cognitive task on postural control in patients with Alzheimer, Parkinson and controls. Thirty-eight participants were instructed to stand upright on a force platform in two experimental conditions: single and dual task. Participants with Parkinson’s disease presented an increase in the coefficient of variation greater than 100 % in the dual task as compared to the single task for center of pressure (COP) area and COP path. In addition, patients with Parkinson’s and Alzheimer’s disease had a higher number of errors during the execution of the cognitive task when compared to the group of elderly without neurodegenerative diseases. The motor cortex, which is engaged in postural control, does not seem to compete with frontal brain regions in the performance of the cognitive task. However, patients with Parkinson’s and Alzheimer’s disease presented worsened performance in cognitive task. Key words: postural control, dual task, Alzheimer’s disease, Parkinson’s disease Resumo—“Tarefa dupla e controle da postura na doença de Alzheimer e na doença de Parkinson”. Pacientes com doen-ças neurodegenerativas utilizam recursos cognitivos para manutenção do controle postural. O objetivo deste estudo foi investigar os efeitos de uma tarefa cognitiva frontal no controle postural em pacientes com Alzheimer, com Parkinson e idosos sem doenças neurodegenerativas. Trinta e oito participantes foram instruídos a ficar em pé sobre uma plata