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Related to Otolith organ: utriculus, Saccule and utricle


A calcareous concretion on the end of a sensory hair cell in the vertebrate ear and in some invertebrates.



a solid formation on the surface of the mechanoreceptor cells in the organs of equilibrium of some invertebrates and all vertebrates. Otoliths of different animals vary in origin, size, and structure: they can be secreted by cells or introduced from outside, for example, grains of sand serve as otoliths in crayfish. Mammalian otoliths are usually crystals of calcite (CaCO3) up to 10 microns (μ.) long and 1–3 μ wide.

As otoliths shift in response to acceleration and changes in body position, they mechanically irritate the underlying ciliated receptor cells, which then send appropriate signals to the brain.

The action of otoliths has been demonstrated in experiments with crayfish. The grains of sand that serve as the crayfish’s otoliths were replaced during molting by iron filings, and a magnet was placed above the animal to attract the filings. The crayfish reversed its sense of orientation, turned over, and swam with its abdomen up.


References in periodicals archive ?
Even if the final physiological cause can be pinned to the vestibular system or otolith organs, the choices pilots make prior to disorientation can tell the tale, as the NASA and NTSB reports show.
Thus it is reasonable to assume that the halibut larvae are subjected to weightlessness or postural control, and their otolith organs are sensitive to changes in position.
Much of his early research focused on understanding how the brain processes ambiguous sensory information, with a specific focus on how signals from the otolith organs in the inner ear are interpreted and processed by the nervous system.
After the fish land, the researchers will examine the subjects' otolith organs, which are used to sense gravity and acceleration.