Chapter 8: Outer and Middle Ear Flashcards
acoustic reflex
a bilateral middle ear muscle contraction in response to a loud sound in one or both ears.
aditus ad antrum
a narrow bony passageway in the posterior bony wall of the middle ear that connects the tympanum to the antrum
annular ligament
a ring-shaped ligament that holds the stapes footplate in the oval window
annulus
a ring-shaped ligament that holds the tympanic membrane in place along its lateral edges.
anterior ligament of the malleus
a ligament that attaches the malleus to the anterior wall of the tympanic cavity.
antihelix
a cartilaginous ridge of the pinna that is medial to and generally parallel to the helix.
antitragus
a small cartilaginous projection of the pinna that is adjacent to the tragus (separated y the internal notch); superior to the ear lobe.
antrum
a small chamber within the mastoid portion of the temporal bone that is posterior to the main middle ear cavity.
auricular tubercle
Darwin’s tubercle
a bump of tissue along the edge of the helix observed in some pinnae.
azimuth estimation
the process of determining the direction in the horizontal plane at which a sound is arriving at the listener.
binaural
related to two ears.
binaural localization cues
localization cues created by differences in the acoustic characteristics of sounds as they arrive at the right ear and left ear
cartilaginous portion of the ear canal
the outer 1/3 of the ear canal formed by a cartilaginous framework
catenary lever (buckling effect)
the anatomic lever created because the Umbo is displaced less than the rest of the tympanic membrane; as a result, the pressure at the Umbo is about two times (6dB) grater that the pressure across the entire membrane.
cave concha
the more inferior of the two parts of the concha; the portion of the concha closest to the external auditory meatus.
cerumen
earwax
chorda tympani
a branch of the facial nerve that crosses the epitympanum from the back to the tympanic cavity to the front just beneath the head of the malleus and incus; joins the lingual nerve to provide taste sensation to the anterior portion of the tongue.
concha
a bowl shaped depression that comprises the deepest groove in the pinna
cone of light
a light reflection off the tympanic membrane seen during otoscopic examination; observed on the anterior inferior quadrant in a normal ear.
crura of the antihelix
the superior portion of the anti helix where it divides to form two folds separated by the triangular fossa.
crus of the helix
the most medial aspect of the helix, which connects the helix to the side of the head and to the conch
cymbal concha
the most superior of the two parts of the concha; the portion of the conch farthest from the external auditory meatus.
(auditory) distance estimation
the process of determining how far one is from a sound source.
elevation estimation
the process of determining the angle between the horizontal plane passing through the ears of a listener and the direct in the vertical plane from which the sound is arriving.
epitympanum
the superior portion of the tympanum
eustachian tube
(auditory tube, pharyngotympanic tube)
the channel that begins on the anterior wall of the middle ear an connects the middle ear cavity with the nasopharyngeal cavity.
external auditory canal
the anatomic tube that begins at the external auditory meatus and extends medially to the tympanic membrane
external auditory meatus
the external opening of the ear canal, located at the medial edge of the pinna
helix
the outer cartilaginous fold of the pinna that curves around the outside edge; it begins at the superior border to the lobule and end at the crus of the helix
hypotympanum
the crest-shaped inferior portion of the middle ear cavity located below the inferior border of the annulus and below the eustachian tube.
incudostapedial joint
the joint formed between the lenticular process of the incus and the head of the stapes.
incus
one of the bones of the inner ear, attached at one end to the malleus ant at the other end to the stapes; known as the anvil in nonprofessional terms.