Special Senses: Balance

By Morgan Downing Alec Hardesty Hope Andrews

Mechanisms of Equilibrium

The equilibrium receptors of the inner ear are called the Vestibular Apparatus. It is divided into two parts1. Static Equilibrium2. Dynamic Equilibrium

Static Equilibrium

Maculae help us know which way is up our down. Each maculae is a patch of receptor cells with their “hairs” embedded in the otolithic membrane.

The otolithic membrane is a gel material containing otoliths or tiny stones made of calcium salts; rolls in response to changes in gravity.

The movement of the otoliths send impulses through the vestibular nerve to the cerebellum

Static Equilibrium

Maculae

Otoliths

Olithic Membrane

Receptor Cell Nerve

Fiber

Dynamic Equilibrium

The Dynamic Equilibrium responds to angled or rotator movements of the head

Crista Apullaris are tufts of hair cells covered with a gel cap called the Cupula

The impulses of theses cells travel up to the vestibular nerve to the cerebellum

Dynamic Equilibrium

Cupula

Cri

sta

am

pu

llari

s

Hair Cell

Other Components of Balance

Although the receptors in the ear control equilibrium, sight and the receptors of muscles and tendons are also important in proving information used for balance to the cerebellum

Disorders

POSITIONAL VERTIGO

Dynamic balance disorder in which the cupula doesn’t tilt properly and causes intense feelings of spinning from slight head movements.

MAL DE DEBARQUEMENT SYNDROME

Feeling of continuously rocking or bobbing after traveling on a boat for long periods of time. This usually goes away a few days after being on land, but severe cases can last years.