Dual-task and task demands in postural control of young adults

• Grant number: 14/03083-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2014
• End date: July 31, 2015
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: José Angelo Barela
• Grantee: Giovanna Gracioli Genoves
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

Postural control involves integration of cues coming from the vestibular, visual, and somatosensory systems to produce appropriate muscle activity. The mechanisms involved in the relationship between sensory information and muscle activity are not yet well known. Recently, there have been questions regarding cognitive involvement in the postural control functioning. Therefore, the aim of this study is to examine the effects of performing a dual task in the relationship between sensory information and body sway in young adults while maintaining upright stance with different task demands. Thirty young adults (aged 18 to 25 years), will be randomly assigned into two groups: easy task (GTF) and difficult task (GTD) group and will stand inside a moving room that will be moved, forward and backward, with amplitude of 0.6 cm and peak-to-peak velocity of 0.6 cm/s. Participants in both groups will perform ten trials, each lasting 60 seconds. In the first trial there will no movement of the room. In the following three trials (2nd, 3th, and 4th), the room will move and participants will not be informed about the visual manipulation. In the 6 subsequent trials, participants will be informed about the room movement and will be asked to resist to the visual information, maintaining the upright position as stable as possible. In three of these trials, participants will perform counting backwards task from 100, with an interval of three (eg, 100, 97, 94, 91, 88... ). The order of the blocks, for the last 6 trials, will be defined randomly. Body sway and movement of the room will be obtained using a motion analysis system (OPTOTRAK 3020, NDI Inc.). The relationship between the movement of the room and body sway will be examined from coherence, gain, phase, and variability of position and velocity. The magnitude of body sway will be examined by calculating the average amplitude of oscillation. Analyses of variance (ANOVAs) will be used to compare the variables between the two groups mentioned and the three task conditions. (AU)