physiology of balance

Last reviewed 01/2018

  • balance is mediated by the vestibular nuclei in the brain stem
  • the labyrinth (a part of the inner ear), is a major organ of our vestibular (balance) system
  • the three semicircular canals of the labyrinth is associated with sensing rotary motion (1)
  • the brain senses the direction and speed of rotation of the head by the movement of fluid in the semicircular canals (1)
  • balance is maintained by the interactions between the labyrinth and other systems in the body, such as the visual and skeletal systems (1)
  • the main inputs into the balance system are the:
    • vestibular labyrinths
    • visual system (eyes)
    • somatosensory system, especially proprioception
  • the main outputs from the vestibular nuclei are:
    • vestibulo-ocular:
      • permitting reflex eye movements related to posture
    • vestibulo-spinal which supply:
      • anti-gravity muscles in the lower limbs
      • reflex arcs which control gait

Reference:

Related pages:

anatomy of the inner ear