Postural control in people with multiple sclerosis: time-to-contact and entropy analyses

Abstract

Multiple sclerosis (MS) is a disease which affects central nervous system and causes demyelination of the axons. This demyelization causes numerous symptoms in people with MS, especially fatigue and impairments in postural control. The relationship between these two symptoms remains poorly understood. The main objective of this internship is to learn nonlinear analyzes of the center of pressure, to discuss the results obtained in Brazil and to deepen the knowledge about MS and postural control. All data will be collected until the internship period. Thirty volunteers (divided into MS group and control group) performed the posture and maximal voluntary contraction evaluations before and after muscle fatigue. In posture assessments, two tasks were proposed (fixation at one point and movement saccadic of the eye). All linear measurements in the anteroposterior and mediolateral axes of the center of pressure will be calculated (displacement, velocity, root mean square and area). Moreover, nonlinear measures of the pressure center (i.e. time-to-contact and entropy) will be performed. These measures may indicate whether this population has the ability to adapt to more challenging postures or after a stimulus such as muscle fatigue. During the internship period, an article will be prepared for publication in the English language. The activities developed in this period will be of great importance in the theoretical learning about MS and nonlinear variables of the center of pressure. (AU)