The labyrinth is the part of the inner ear that is responsible for maintaining balance, i.e. the correct position of the body in space. Where exactly is the labyrinth located? How is it built? Which parts of the labyrinth are responsible for orientation in the field and react to changes in body position?
The labyrinthis a small inner part of the ear located in the rocky part of the temporal bone. The labyrinth contains the receptors of the sense of hearing and the sense of balance, defined as the sense of balance and orientation in space.
How is the labyrinth built?
The labyrinth is divided into bony and membranous.Bone labyrinthis a space made of cavities and canals, in which there is another type of labyrinth - membranous labyrinth responsible for hearing and balance.
The membranous labyrinthconsists of several parts. They are:
- cochlear labyrinth , which consists mainly of the cochlear duct, colloquially called a snail. It is an organ focused on receiving sounds
- structures that make up the organ of equilibrium:
- vestibule ( vestibular labyrinth ) - cavity of irregular shape being the middle part of the labyrinth. It connects to the cochlea at the front and semicircular canals at the rear. It contains a tube and a bag. They play the main role in maintaining static balance - membranous semicircular canals (whose length ranges from 1.5 to 2 cm) leave the atrium and return to it again after 2/3 of the circle. They are responsible for maintaining the kinetic balance
So-called the cochlea houses a spiral organ containing approximately 20,000 auditory receptor cells that perceive sounds. Each cell of this organ perceives vibrations of a certain frequency and intensity. Thanks to this, a person can distinguish between the pitch of tones, the intensity of the sound and its timbre. The spiral canal is divided by a bone spiral plate and the wall of the membranous cochlear duct into two spaces: the vestibule stairs and the drum stairs.
Receptorssense of balanceare located in the vestibular organ of the inner ear, i.e. in the parts of the labyrinth called the semicircular canals and the vestibule.
The three semicircular canals (anterior, posterior, and lateral) are filled with fluid and arranged in three perpendicular planes: frontal, sagittal, and horizontal. It is in themsense of space because they respond to the rotation of the body.
In turn, the organs located in the cochlea atrium, i.e. in the vestibular labyrinth, react to linear acceleration (change of position up, down, in a straight line). These are the pollen tube and the bag.
In each of these organs there is a sensory structure called the macula. Due to its arrangement (vertical in the bag and horizontal in the tube), the bag is sensitive to changes in acceleration in the vertical direction (e.g. gravity), and the pollen tube detects deviations of the head from the vertical.
How does the labyrinth work?
Movement, both linear and rotational, causes the fluid filling the labyrinth structure to move. In this way, the sensitive sense cells that are located in these labyrinth structures are irritated. Irritation in these cells travels through the nervous system to the brain, where it is read as a sensation of movement.
For this reason, the efficiency of the functioning of the sense of balance from the close cooperation between the labyrinth and the cerebellum, which is responsible for the coordination of movements that maintain the correct position of the body.
Read:
- Symptoms of labyrinth diseases
- Labyrinth diseases