What is the sense of balance?

The sense of balance is a sensory perception that gives the body information about its position in space. The sense of balance is used to orientate oneself in space and to adopt a balanced posture, both at rest and in motion. The body receives information from the inner ear, the eyes and the joints.

These all converge in the brain stem and are processed there. On the one hand, the inner ear consists of the two macular organs sacculus and utriculus, which perceive vertical (e.g. when driving an elevator) and horizontal (e.g. when starting a car) acceleration.

On the other hand, it is composed of the three archways, which can detect rotational movements in any direction in space. The eyes receive visual information and also pass this on to the brain stem. In the joints, we also have so-called proprioceptors that determine the position of the respective joint.

If the brain receives contradictory information, dizziness may occur. For example, if you are inside a ship in a heavy sea, the organ of equilibrium of the inner ear mediates strong accelerations in many different directions. The eye, however, wants to convey to us that the room is at rest.

This triggers a feeling of dizziness in the person affected. The organ of equilibrium can be checked for its functionality in various ways. The simplest way of testing is by walking and standing tests with open and closed eyes.

Another possibility is the swivel chair test. Here the patient is rotated on a chair around its own axis for a longer period of time. After deceleration, a nystagmus, which depends on the direction of rotation, occurs in healthy persons as a result of the stimulation of the archways.

Furthermore, the vestibular organ (organ of balance) can also be checked by means of caloric stimulation. For this purpose, the horizontal arches are excited one after the other with cold or warm water, which also causes a nystagmus with a certain direction in healthy persons. A nystagmus is eye movements with a slow and a fast component in the horizontal (right, left).The direction of the fast component gives the nystagmus its name (right or left nystagmus).