The outer ear, external ear, or auris externa is the external part of the ear, which consists of the auricle and the ear canal. It gathers sound energy and focuses it on the eardrum.
Anotia describes a rare congenital deformity that involves the complete absence of the auricle, the outer projected portion of the ear, and narrowing or absence of the ear canal. This contrasts with microtia, in which a small part of the auricle is present. Anotia and microtia may occur unilaterally or bilaterally. This deformity results in conductive hearing loss, deafness.
Articles related to anatomy include:
Auriculotherapy is a form of alternative medicine based on the idea that the ear is a micro system and an external organ, which reflects the entire body, represented on the auricle, the outer portion of the ear. Conditions affecting the physical, mental or emotional health of the patient are assumed to be treatable by stimulation of the surface of the ear exclusively. Similar mappings are used by several modalities, including the practices of reflexology and iridology. These mappings are not based on or supported by any medical or scientific evidence, and are therefore considered to be pseudoscience.
An ear is the organ that enables hearing and body balance using the vestibular system. In mammals, the ear is usually described as having three parts: the outer ear, the middle ear and the inner ear. The outer ear consists of the pinna and the ear canal. Since the outer ear is the only visible portion of the ear in most animals, the word "ear" often refers to the external part alone. The middle ear includes the tympanic cavity and the three ossicles. The inner ear sits in the bony labyrinth, and contains structures which are key to several senses: the semicircular canals, which enable balance and eye tracking when moving; the utricle and saccule, which enable balance when stationary; and the cochlea, which enables hearing. The ear is a self cleaning organ through its relationship with earwax and the ear canals. The ears of vertebrates are placed somewhat symmetrically on either side of the head, an arrangement that aids sound localization.
Sound localization is a listener's ability to identify the location or origin of a detected sound in direction and distance.
An equal-loudness contour is a measure of sound pressure level, over the frequency spectrum, for which a listener perceives a constant loudness when presented with pure steady tones. The unit of measurement for loudness levels is the phon and is arrived at by reference to equal-loudness contours. By definition, two sine waves of differing frequencies are said to have equal-loudness level measured in phons if they are perceived as equally loud by the average young person without significant hearing impairment.
Cauliflower ear is an irreversible condition that occurs when the external portion of the ear is hit and develops a blood clot or other collection of fluid under the perichondrium. This separates the cartilage from the overlying perichondrium that supplies its nutrients, causing it to die and resulting in the formation of fibrous tissue in the overlying skin. As a result, the outer ear becomes permanently swollen and deformed, resembling a cauliflower, hence the name.
Otoplasty is a procedure for correcting the deformities and defects of the auricle, whether these defects are congenital conditions or caused by trauma. Otoplastic surgeons may reshape, move, or augment the cartilaginous support framework of the auricle to correct these defects.
Presbycusis, or age-related hearing loss, is the cumulative effect of aging on hearing. It is a progressive and irreversible bilateral symmetrical age-related sensorineural hearing loss resulting from degeneration of the cochlea or associated structures of the inner ear or auditory nerves. The hearing loss is most marked at higher frequencies. Hearing loss that accumulates with age but is caused by factors other than normal aging is not presbycusis, although differentiating the individual effects of distinct causes of hearing loss can be difficult.
The ear canal is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the auricle to the eardrum and is about 2.5 centimetres (1 in) in length and 0.7 centimetres (0.3 in) in diameter.
In audiology and psychoacoustics the concept of critical bands, introduced by Harvey Fletcher in 1933 and refined in 1940, describes the frequency bandwidth of the "auditory filter" created by the cochlea, the sense organ of hearing within the inner ear. Roughly, the critical band is the band of audio frequencies within which a second tone will interfere with the perception of the first tone by auditory masking.
The tragus is a small pointed eminence of the external ear, situated in front of the concha, and projecting backward over the meatus. It also is the name of hair growing at the entrance of the ear. Its name comes the Ancient Greek tragos, meaning 'goat', and is descriptive of its general covering on its under surface with a tuft of hair, resembling a goat's beard. The nearby antitragus projects forwards and upwards.
The antihelix (anthelix) is a part of the visible ear; the pinna. The antihelix is a curved prominence of cartilage parallel with and in front of the helix on the pinna.
Hearing loss with craniofacial syndromes is a common occurrence. Many of these multianomaly disorders involve structural malformations of the outer or middle ear, making a significant hearing loss highly likely.
The anterior auricular branches of the superficial temporal artery are distributed to the anterior portion of the auricula, the lobule, and part of the external meatus, anastomosing with the posterior auricular. They supply the external acoustic meatus and the visible part of the ear.
A cartilage piercing can refer to any area of cartilage on the body with a perforation created for the purpose of wearing jewelry. The two most common areas with cartilage piercings are the ear and the nose. Many people outside of the body modification community often informally use the term "cartilage piercing" to refer a helix piercing. The cartilage ear piercing is known to be more sore than the lobe as in the cartilage there is less blood so it takes longer to heal.
The following outline is provided as an overview of and topical guide to human anatomy:
An accessory auricle is considered a developmental anomaly resulting from the persistence of a structure which variably recapitulates the normal external ear.
The neural encoding of sound is the representation of auditory sensation and perception in the nervous system. The complexities of contemporary neuroscience are continually redefined. Thus what is known of the auditory system has been continually changing. The encoding of sounds includes the transduction of sound waves into electrical impulses along auditory nerve fibers, and further processing in the brain.
