Light touch contribution to balance in normal bipedal stance

• Published in: Experimental brain research Vol. 125; no. 4; pp. 521 - 524
• Main Authors: CLAPP, S, WING, A. M
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.04.1999
• Subjects: Adult; Biological and medical sciences; Fingers - physiology; Fundamental and applied biological sciences. Psychology; Hand Strength - physiology; Humans; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Postural Balance; Posture - physiology; Pressure; Space life sciences; Touch - physiology; Vertebrates: nervous system and sense organs; Human; Tactile sensitivity; Sensorimotor coordination; Center of mass; Orthostatism; Motor control; Hand; Posture
• ISSN: 0014-4819; 1432-1106
• DOI: 10.1007/s002210050711

It has previously been shown that light contact with the finger tip on a fixed surface reduces centre of pressure (CoP) fluctuations in the frontal plane when standing in an unstable posture with the feet in line (tandem Romberg stance). Positive cross-correlations between horizontal finger forces and CoP fluctuations with finger forces exhibiting a phase lead suggest the hand provides sensory input for postural stability. The present study investigates whether this is the case for normal posture. We report reduced CoP fluctuations in the sagittal plane when light touch is permitted during normal bipedal stance. Moreover, we find positive crosscorrelations between finger tip forces and CoP fluctuations which are of similar magnitude and phase lag to those observed in tandem Romberg stance. This shows the utility of hand touch input for regulation of normal upright posture as well as inherently unstable postures such as tandem Romberg.