Experimental Brain Research

, Volume 114, Issue 1, pp 163–169

The significance of somatosensory stimulations to the human foot in the control of postural reflexes

  • G. Wu
  • Jin-Hsien Chiang
RESEARCH ARTICLE

DOI: 10.1007/PL00005616

Cite this article as:
Wu, G. & Chiang, JH. Exp Brain Res (1997) 114: 163. doi:10.1007/PL00005616

Abstract

 The purpose of this study was to investigate the possible pathways in the somatosensory system that relate to the postural reflexes in the leg muscles during a sudden, toes-up platform rotation. The inputs to the cutaneous mechanoreceptors in the sole of the foot as well as to the joint receptors in the ankle joint were modulated by standing on different supporting surfaces and by immobilizing the ankle joints; and three leg muscle responses (characterized by short latency, medium latency, and long latency) to the platform movement were recorded in 15 healthy young subjects. It was found that: (1) the short latency was not affected by the changes in either plantar pressure or ankle joint movement; (2) the medium latency was regulated by the plantar pressures under the foot, as sensed by the cutaneous mechanoreceptors in the sole of the foot, and by the ankle joint movement, as perceived by the joint receptors in the ankle joint; (3) the long latency was also related to the ankle joint movement, but this relation seems to be modulated by the plantar pressures under the foot; and (4) both medium and long latencies were well correlated with the time derivative of the pressure difference between the forefoot and the rear foot regions (r=0.7), as well as with the static pressure in the antagonist foot region (r>0.6).

Key words Muscle receptorsJoint receptorsCutaneous mechanoreceptorsPlantar pressureLeg EMG signalsHuman

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • G. Wu
    • 1
  • Jin-Hsien Chiang
    • 2
  1. 1.Department of Physical Therapy, The University of Vermont, Burlington, VT 05405, USAUS
  2. 2.Bioengineering Program, The Pennsylvania State University, University Park, PA 16802, USAUS