Motor Imagery Task Alters Dynamics of Human Body Posture.

BACKGROUND AND PURPOSE

Motor imagery (MI) has gained increasing attention in rehabilitation and sports as a cognitive strategy to enhance performance and recovery. However, the mechanisms underlying MI's influence on postural control are not yet fully understood. This study aims to investigate the immediate effects of MI on the dynamics of the center of pressure (COP), a critical measure of postural stability, and to develop a mathematical model to describe these changes.

METHODS

Twenty-four healthy young adults participated in an experiment consisting of four conditions: normal standing with open eyes (NS), standing with closed eyes (CE), kinesthetic MI of mediolateral sway (ML MI), and MI of anteroposterior sway (AP MI). COP data were recorded and compared across these conditions. A mathematical model was developed to describe the nonlinear dynamics of COP and the influence of MI on these patterns.

RESULTS

MI tasks resulted in significant changes (p < 0.05) in variables such as COP path length during MI tasks compared to NS and CE conditions. In addition, alterations in the COP align directionally with the imagined movements, for example, in the ML MI condition, Root Mean Square (RMS) in the x-direction, but not the y-direction, is significantly different from CE.

DISCUSSION

These findings support the psycho-neuromuscular theory of MI, which proposes that imagining a movement activates associated motor circuits at low intensity. This supports the potential of MI to induce specific postural adjustments, supporting its use as a therapeutic tool in rehabilitation to target motor circuits and improve postural control. While promising, further research is needed to explore the underlying mechanisms and validate these findings across diverse populations to maximize the practical application of MI in clinical settings.