Pinna
What is another name for the pinna?
Auricle
Where does the external auditory canal terminate?
The tympanic membrane
What are the two sources of cues?
Monaural and Binaural
Name one way that the outer ear is protective
-Through the migration of cerumen
-Length/complex pathway of the ear canal
Isthmus
- Narrowing that connects two larger parts
- Junction of the cartilaginous portion and osseous portion of the external auditory canal
What is number one on the diagram?
Antitragus
What is the volume of the external auditory canal?
1.4cc
What is another name for the angle of source?
(front, back, left, right)
Azimuth Estimation
What is the outer ear protecting the tympanic membrane from?
Foreign bodies and changes in humidity/temperature
-Stems from the Latin word for bone, oss
-Examples: osseous portion, ossicles
What is number two on the diagram?
Triangular Fossa
True or False: The entire external auditory canal is surrounded by bone
False: The most lateral third is surrounded by cartilage (cartilaginous portion) while the remaining 2/3 is surrounded by bone (osseous portion)
What age does elevation estimation develop?
Around 18 months of age
What gives the outer ear a resonance frequency?
The shape and size of the outer ear
Tympanum
-Eardrum
-The tympanic membrane
What part of the pinna contains sebaceous glands?
The concha contains sebaceous glands (the ear canal also contains these glands)
True or False: The top of the external auditory canal is 3.1 cm
False: The top of the external auditory canal is 2.5 cm long and the bottom is 3.1 cm
When do head shadows occur?
When the wavelength is smaller than the head size
What is the formula for frequency?
Fn=(2n-1)c/4L
Crus
-Leg
-An elongated part of an anatomical structure (superior crus of antihelix & inferior crus of antihelix, anterior and posterior crura of stapes)
The cartilage connects to what parts of the temporal bone?
The zygomatic and mastoid parts of the temporal bone
What is the diameter of the isthmus?
0.4 cm
If a person hears a sound in their left ear before their right ear, which localization cue is this? What frequency would this sound be, low or high?
Interaural Time Difference and a low frequency sound
The highest intensity range occurs at what frequency due to the resonance of the external auditory canal
3kHz
Fossa
-Ditch
-Triangular Fossa, Scaphoid Fossa (a shallow depression, hollow)