OTOLITH-CANAL CONTROL MECHANISMS IN POSTURE AND MOVEMENT

  • Horak, Fay (PI)
  • Peterson, Barry (PI)
  • MacPherson, Jane (PI)
  • Goldberg, J.A.Y. (PI)
  • Russell, Charles (PI)
  • Baker, James (PI)

Project: Research project

Description

This Center is designed to define the contributions of the vestibular
system to the control of balance, posture and locomotion through an
integrated series of ground-based studies, three examining the
vestibular-neck (vestibulocollic) reflex and three the vestibulospinal
control of standing posture. One theme of the Center is to exploit the
synergy between these two set of studies to produce the first complete
whole body model of posture. Any model that is to lead to an adequate
understanding of the postural system must incorporate and interrelate
mechanisms that stabilize the head in space, the trunk with respect to
the head and body center of mass with respect to gravity. Heretofore no
investigator or group has had the broad array of skills and insights to
attempt such a model or to undertake the interactive experiments needed
to obtain the data upon which it must be based. This Center will provide
the skills and resources to accomplish this important task which the
field has been awaiting for a long time. The second theme of the Center is to focus upon the vestibular otolith
organs and the sensory motor responses that occur when they are
stimulated by gravitational forces or linear motions. Projects 1, 2 and
6 will bring on line new devices designed specifically to study otolith
systems. Modelers involved in Projects 1, 2, 4 and 5 will simulate and
model for the first time the role of neural pathways originating in
otolith organs in stabilization of the head and body and in locomotion.
Recordings proposed in Project 2 will yield the first 3-dimensional
analysis of otolith signals at the level of vestibulospinal neurons.
Collectively these activities will greatly increase our knowledge of
otolith systems, which are of special importance for understanding how
the neuro-vestibular system senses and adapts to the alteration in
gravity that occurs when a space craft enters orbit and returns to earth
with attendant problems of disorientation and dysequilibrium. A third theme of the Center is its extensive use of computational
modeling. Projects 1 and 4 share the use of an elegant new biomechanical
model that allows one to construct accurate models of musculo-skeletal
systems, whose kinetic properties can then be simulated under a wide
variety of conditions. Projects 1 and 5 employ non-linear systems models
to simulate how central nervous system control of head or body position
interacts with body biomechanics. Project 2 uses new neural network
modeling approaches to analyze the function of circuits that incorporate
the known connectivity of vestibulocollic pathways. Our goal is for
these modeling efforts to coalesce into a multi-level model that both
simulates postural stabilizing responses observed by us and others and
suggests further experiments that will more effectively illumine the
functions of the vestibulospinal system. The Center will also have a training component designed to give pre- and
postdoctoral trainees unique opportunities to work with outstanding
vestibular physiologists and modelers and to participate in work on
several Center projects, thus contributing to the cross-fertilization
taking place within the Center.
StatusFinished
Effective start/end date8/6/937/31/99

Funding

  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health

Fingerprint

Otolithic Membrane
Posture
Astronauts
Weightlessness
Torque
Computer Simulation
Leg
Joints
Head
Muscles
Health
Semicircular Canals

ASJC

  • Medicine(all)
  • Neuroscience(all)