Does the Level of Difficulty in Balancing Tasks Affect Haptic Sensitivity Via Light Touch?

ABSTRACT.

The purpose of this study was to determine whether the contribution of bimanual light touch varies according to the difficulty level of postural tasks (e.g., vision occlusion, height of support surface). Fourteen healthy young adults each were asked to stand in a tandem position, on a 20-cm height balance beam. Postural tasks included light touch and no touch conditions in two vision conditions, nonvision and full vision. The root mean square of amplitude of oscillation (mediolateral), mean velocity, ellipse area, and path length of the center of pressure revealed that touch conditions reduced sway to a greater extent in the elevated support surface, nonvision condition. Highly unstable balance tasks increase the optimization of light touch and affect the attenuation of postural sway.

Keywords:

• Haptic perception
• light touch
• postural control
• task difficulty

Acknowledgments

The authors wish to thank the participants who volunteered for this study. They also wish to thank Debra Frances Campbell, PhD, for her kind and patient reviews of this manuscript, and the anonymous JMB’ reviewers for their insightful comments.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 Haptic anchoring is a task in which an individual (haptically) integrates the properties of a nonrigid tool (i.e., holding a pair of weights attached to strings, an “anchor system,” which remains in contact with the floor) while simultaneously performing a balance task. Typically, haptic anchoring helps to improve postural control (Mauerberg-deCastro, 2004; Mauerberg-deCastro et al., 2014).