Otolith apparatus

Otolith the device is located in the inner ear receptor education vestibular analyzer, adequate stimuli for which you are changing the position of the head, the effects on the body by gravitational forces, straight centrifugal accelerations. Otolith apparatus (Fig) occupies an area of so-called hearing spots inside the membranous sacs vestibule (maculae utriculi et sacculi) and presents sensitive voloshkovi cells, among which are the supporting cells. Protoplasmatic the processes of the past, as the hairs of nerve cells, immersed in gelatinoasa substance - otolith the membrane covering the cellular education. In the upper part of the membrane of disseminated crystals of calcium bicarbonate - otoliths, which increases its share in comparison with the share of environmental endolymph more than two times. This difference in weight is a physical principle of the normal functioning of the receptors.
According to the theory Breuer, irritation otolith apparatus is due to the tangential displacement otolith membrane and bending associated with drink sensitive cells. Such offsets occur under the influence of inertial forces, developing as a result of influence on an organism of linear accelerations in force in all directions. Existing experimental data allow to consider otolith apparatus as the organ of balance and spatial feelings (C. M. Bekhterev, I. S. of Beriev). Violations of spatial representations of the person in conditions of weightlessness (space flights) are determined by the change reflex relationship O. A. as specific gravireceptor with other afferent systems involved in the perception of space (visual, motor, skin and others).
Among motor reflexes caused with O. a., the most important - tonic deviations eyes, and postural and installation reflexes. The latter can be observed in humans at the fall, during sports games and exercises.
To study the function of Acting as. in the clinic, use different methods of vestibulometry (see).
In special studies otolith apparatus related to selection and training of pilots, sailors, and astronauts are widely used centrifuges, inclined tables, swivel chair on unstable support. Assessment of the status of O. A. is given on the basis of nystagmus provisions, breach of compensatory eye movements, gait and balance, illusory sensations spatial position, dizziness, vegetative disorders (sweating, paleness, nausea, vomiting).
These symptoms in different combinations can occur when neuritis n. vestibulocochlearis, skull injuries, tumors of the brain, infectious diseases and food poisoning. The treatment is of cause, peace, salt-free diet; for eliminating nausea and vomiting appoint platifillin with caffeine bromide and potassium (Plathiphillini 0,005 g, Coffeini 0.1 g, Kalii bromati 0.15 g), subcutaneous atropine solution (Sol. Atropini sulfurici 0.1% to 1 ml).
Cm. also the Vestibular apparatus.

the scheme of the structure of the macula lutea The scheme of the structure of the macula lutea (Clara):
1 - otoliths;
2 - gelatinoasa weight;
3 - hairs;
4 - sensitive cells;
5 - bearing cells;
6 - myelinated nerve fibers.