WordNet

a small yellowish central area of the retina that is rich in cones and that mediates clear detailed vision (同)macula_lutea, macular_area, yellow_spot

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/02/28 13:56:08」(JST)

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The macula of the utricle, or utricular macula is the region of the utricle that receives the utricular filaments of the vestibulocochlear nerve. The portion of the utricle that forms the macula forms a sort of pouch or cul-de-sac, with a thickened floor and anterior wall. The macula of utricle allows a person to perceive changes in longitudinal acceleration (in horizontal directions only).

Layers

The macula consists of three layers.

The bottom layer is made of sensory hair cells which are embedded in bottom of a gelatinous layer. Each hair cells consists of 40 to 70 steriocilia and a kinocilium, which lies in the middle of the steriocilia and is the most important receptor.

On top of this layer lie calcium carbonate crystals called statoconia or otoliths. The otoliths are relatively heavy, providing weight to the membrane as well as inertia. This allows for a greater sense of gravity and motion.

The gelatinous layer and the statoconia together are referred to as the otolithic membrane, where the tips of the stereocilia and kinocilium are embedded. When the head is tilted such that gravity pulls on the statoconia the gelatinous layer is pulled in the same direction also causing the sensory hairs to bend.

Signals

Unbent and at rest hairs in the macula have a base rate of depolarization of 90-100 action potentials a second. The brain suppresses this, and we ignore it and know that our body is stabilized. If the head moves or the body accelerates or decelerates, then bending occurs.

Depending on the direction of bending, the hair cells will either be excited or inhibited resulting in either an increase or decrease in firing frequency of the hair cells.

The macula is also sensitive to linear acceleration as the inertia possessed by the statoconia can also shift the gelatinous layer during increases and decreases in linear velocity.

References

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

External links

http://www.neurophys.wisc.edu/h&b/textbook/chap-7.html#Obj2

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English Journal

Are accessory hearing structures linked to inner ear morphology? Insights from 3D orientation patterns of ciliary bundles in three cichlid species.

Schulz-Mirbach T1, Ladich F, Plath M, Metscher BD, Heß M.
Frontiers in zoology.Front Zool.2014 Mar 19;11(1):25. doi: 10.1186/1742-9994-11-25.
BACKGROUND: Cichlid fishes show considerable diversity in swim bladder morphology. In members of the subfamily Etroplinae, the connection between anterior swim bladder extensions and the inner ears enhances sound transmission and translates into an improved hearing ability. We tested the hypothesis
PMID 24645675

Efficient siRNA transfection to the inner ear through the intact round window by a novel proteidic delivery technology in the chinchilla.

Qi W1, Ding D2, Zhu H3, Lu D4, Wang Y3, Ding J3, Yan W1, Jia M1, Guo Y1.
Gene therapy.Gene Ther.2014 Jan;21(1):10-8. doi: 10.1038/gt.2013.49. Epub 2013 Oct 10.
The use of small-interfering RNA (siRNA) has great potential for the development of drugs designed to knock down the expression of damage- or disease-causing genes. However, because of the high molecular weight and negative charge of siRNA, it is restricted from crossing the blood-cochlear barrier,
PMID 24108151

[Inner ear morphological study of guinea pigs with acoustically evoked short latency negative response].

Huang WQ1, Li ZM, Xu L, Nong DX, Tang AZ, Qin HH, Yang T.
Zhonghua er bi yan hou tou jing wai ke za zhi = Chinese journal of otorhinolaryngology head and neck surgery.Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi.2012 May;47(5):394-9.
OBJECTIVE: To establish a model of ototoxicity in guinea pigs with acoustically evoked short latency negative response (ASNR) and verify the responsible organ of ASNR based on microscopic characteristics of basal membranes, saccules, utricles and ampulla canalis semicircularis of the inner ear.METHO
PMID 22883582

Japanese Journal

良性発作性頭位めまい症 : 臨床疫学と病態生理

耳鼻咽喉科臨床 94(9), 763-776, 2001-09-01
NAID 10008097437

レーザー内耳手術の術後経過:-聴力・平衡機能について-

日本レーザー医学会誌 15(Supplement), 383-386, 1994
NAID 130004702482

Morphological Changes of the Vestibular Labyrinth by Experimental Perilymph Fistula

The Showa University Journal of Medical Sciences 6(1), 97-103, 1994
NAID 130004070337

「卵形嚢斑」

Macula of utricle
	illustration of otolith organs showing detail of utricle, otoconia, endolymph, cupula, macula, hair cell filaments, and saccular nerve
Details
Identifiers
Latin	macula utriculi
Dorlands; /Elsevier	m_01/12509297
TA	A15.3.03.083
FMA	74960
	Anatomical terminology [edit on Wikidata]