Balance Organ (Vestibular Apparatus): How it works

What is the organ of balance?

The sense of balance comes from the interaction of the organ of balance in the inner ear with the eyes and the central processing of information in the brain.

The organ of balance (ear) consists of two different systems:

  • The static system responds to linear motion and gravity.
  • The arcuate system registers rotatory movements.

Static system

The function of the macular organ

Since the calcium crystals have a higher specific gravity than the endolymph, they follow gravity and, when we stand upright and hold our head straight, they push on the sensory cilia of the macula of the utriculus, which are horizontal. They pull on the sensory hairs of the macula of the saccule, which are vertical. This creates the sensation of an upright, regular body position – the sense of balance (ear).

These changes in state are transmitted to the central nervous system, which then corrects the state of tension (tone) of the skeletal muscles in an appropriate manner as a reflex. The goal is always the upright posture of the body, which should prevent falling.

Archways

Adaptation to various changes in position

The work of the organ of equilibrium – the permanent orientation in three-dimensional space – is very important in order to be able to adapt quickly to changes in body posture. The interaction of both systems of the vestibular organ (with five sensory endpoints each – the two macular organs and the three arcades) allows the position and movements of the head to be determined very precisely.

What problems can the organ of balance cause?

The most common symptom of disorders of the organ of balance is dizziness associated with nystagmus (eye tremor).

When a system of the vestibular organ becomes diseased (inflammation, tumor, Meniere’s disease, etc.) or suddenly fails, there is a preponderance of information from the healthy side. The consequences are vestibular nystagmus (eye tremor) and vestibular vertigo.

In travel or seasickness, different information about the position of the body reaches the brain from the organ of equilibrium, causing dizziness and nausea.