TITLE:
About the structure of posturography: Sampling duration, parametrization, focus of attention (part II)
AUTHORS:
Patric Schubert, Marietta Kirchner, Dietmar Schmidtbleicher, Christian T. Haas
KEYWORDS:
Center of Pressure; Sample Duration; Posturographic Parameters; Exploratory Factor Analysis; Nonlinear Methods; Dual-Task; Focus of Attention
JOURNAL NAME:
Journal of Biomedical Science and Engineering,
Vol.5 No.9,
September
19,
2012
ABSTRACT: There exists a great variety of posturographic parameters which complicates the evaluation of center of pressure (COP) data. Hence, recommendations were given to use a set of complementary parameters to explain most of the variance. However, it is unknown whether a dual task paradigm leads to different parametrization sets. On account of this problem an exploratory factor analysis approach was conducted in a dual task experiment. 16 healthy subjects stood on a force plate performing a posture-cognition dual task (DT, focus of attention on a secondary task) with respect to different sampling durations. The subjects were not aware of being measured in contrast to a baseline task condition (BT, internal focus of attention) in the previously published part I. In compareson to BT a different factor loading pattern appears. In addition, factor loadings are strongly affected by different sampling durations. DT reveals a change of factor loading structure with longer sampling durations compared to BT. Specific recommendations concerning a framework of posturographic parametrization are given.