A&P Flashcards
1
Q
Outer Ear
Auricle/Pinna
A
Helps localize sound
2
Q
Outer Ear
External Auditory Canal/Meatus
A
- Travels from pinna to tympanic membrane (ear drum)
- Curved like an “s”
- Special cells that secrete cerumen (ear wax)
- Cerum lubricates & cleans canal
- Protects ear from fungi, bacteria & small insects
3
Q
Middle Ear = air-filled cavity
Ossicular Chain
A
- Transmits sound efficiently with no distortion
- Amplifies sound by approx. 30 dB before transmitting it into the fluids of inner ear
4
Q
3 bones in Ossicular Chain
A
- Malleus (hammer) - largest of 3. Touches the TM & Incus. Vibration of TM is transmitted to TM.
- Incus (anvil) - malleus & incus connected in tight joint = very little movement. Attached to stapes
- Stapes (stirrup) - attached to incus & oval window of cochlea which leads to inner ear.
5
Q
Middle Ear Tympanic Membrane (ear drum)
A
- Elastic, thin & cone-shaped
- Vibrates in response to sound pressure (entire for low-freq, only portions for high-freq)
- Sensitive. Easily ruptured by Q-tip, hairpin, explosions, sudden pressure changes.
- Can heal. If ruptured then scar tissue reduces mobility -> hearing
6
Q
Middle Ear
Muscles & Reflexes
A
- Loud, damaging noises (75-95 dB) cause these muscles to contract = acoustic reflex
- Decreases harmful sounds by 10 dB for only 3 min.
- Both muscles work together or they don’t - reflex.
- TTS (temporary threshold shift) - decrease in hearing, due to long exposure to hazardous noise (concerts)
- Tinnitus - ringing in ear due to damaged cochlea or inner ear.
7
Q
Tensor Tympani & Stapedius Muscle together…
A
Dampen vibrations of TM & Ossicular chain
8
Q
Tensor Tympani
A
- CN V Trigeminal
- Tenses TM so vibrations are reduced
“Contraction of muscle causes the TM to move medially & anteriorly”
9
Q
Stapedius Muscle
A
- Smallest muscle in body
- CN VII Facial
- Stiffens ossicular chain so vibrations are reduced
- “Contraction causes the head to move posteriorly at the right angles to direction of ossicular chain”
10
Q
Eustachian Tube
A
- Connects middle ear to nasopharynx
- Helps maintain equal air pressure within outside middle ear
- Opened with: Tensor & Levator Veli Palatini
- Reason for repeat ear infection or otitis media, esp. in infants
11
Q
Inner Ear
Cochlea
A
- Function: Hearing
- Stapes pushes into oval window -> mech. vibrations of sound
- 1.5 in. when stretched out & is filled with endolymph
- Basilar Membrane = Floor of Cochlea
12
Q
Tonotopic Organization
A
- Low freq. stim the tip of the basilar membrane & high freq. stim. base of basilar membrane.
13
Q
Inner Ear
Cochlea
Organ of Corti
A
- “Bathed” in endolyph & contains cilia which respond to vibrations
- Transforms mech. vibrations into electrical energy which can be read by CN VIII (vestibulocochlear)
14
Q
Inner Ear
Vestibular System
A
- Balance = Ear’s primary function!
- Related to movement, balance & body posture
- Semicircular canals = equilibrium
- Vestibular-Ocular Reflex = visual stabilization during active head movement
- “Eyes & ears need to say the same thing or you get dizzy/sick”
15
Q
How we hear
A
- Longitudinal waves move TM which moves ossicular chain
- Stapes pushes into oval window creating wavelike movement in perilymph
- Reissner’s membrane moves vibrations into Organ of Corti & endolymph, then into basilar membrane
- Mech. vibrations are turned into electrical energy, which can be read by CN VIII vestibulocochlear or it doesn’t work
- Most aud. nerve fibers decussate at brainstem -> contralateral pathways allowing comparison of sound signals from both ears - localization & interpretation
- Sound sent to primary auditory area in temp. lobe
16
Q
VSLIM pathway names
A
Ventral Dorsal Cochlear Nucleus Superior Olivary Complex Lateral Lemniscus Inferior Colliculus Medial Geniculate
17
Q
VSLIM pathway
A
- Aud. nerve carries signal to brainstem & synapses to cochlear nucleus
- Aud. info split into at least two streams
- Aud. nerve fibers go into ventral cochlear nucleus
- Ventral Cochlear nucleus cells project to nuclei in medulla called superior olive.
- Superior olive: compare minute diff. of timing & loudness to determine direction sound came from
- Superior olive projects to inferior colliculus via lateral lemniscus
- 2nd stream of info starts in dorsal cochlear nucleus to analyze quality of sound (bet vs. bat & debt)
18
Q
Carhart-Jerger Modified Hughson Westlake Procedure for Finding Threshold
A
Method for finding threshold
Golden Standard
Not done by SLPs
19
Q
Dr. Tice’s 5 Rules
A
- Normal
ACT normal, BCT normal, don’t differ by 10 dB or more - Conductive Dysfunction
ACT normal, BCT normal, differ by 10 dB or more - Conductive
ACT not normal, BCT normal, BCT better by 10 dB or more - Sensorineural
ACT not normal, BCT not normal, don’t differ by 10 or more - Mixed
ACT not normal, BCT not normal, BCT better by 10 or more
20
Q
SPL (sound pressure level)
A
No clear definition, but poss. used to determine loudness
Normal speech = 50-70 dB SPL, Airplane = 100 dB SPL, Painful = 140+ dB SPL
21
Q
HL (hearing level)
A
Lowest intensity of sound necessary to stimulate auditory system.
Used in audiometry
22
Q
Common Speech Characteristics in the Hearing Impaired population
A
- Sound distortion (esp. fricatives & stops)
- Omission of initial & final consonants
- Reduction of Consonant Cluster
- Substitution of Voiced for Voiceless consonants (g/d)
- Omission of /s/ in almost all positions at word level
- Substitution of nasals for oral consonants (mat for bat)
- Increased vowel duration
- Imprecise vowel production
- Epenthesis for consonant blends (Eh-Stop)
23
Q
Common Language Characteristics in Pre-lingual Deaf Individuals
A
- Limited sentence types
- Reduced length & complexity in sentences
- Difficulty understanding/producing compound, complex, & embedded sentences
- Occasionally irrelevant speech - non-sequiturs
- Insufficient background info
- Limited oral comm. - lack of elaborated speech
- Diff. understanding proverbs, metaphors, & abstract
- Slower acquisition of gramm. morphemes
- Omission or inconsistent use of morphemes (past-tense, plural inflection, sing. s, indefinite pronouns, present progressive -ing, prepositions & conjunctions)
- Poor Reading Comp
- Writing reflecting oral lang. problems
24
Q
Voice & Resonance Issues with Hearing Impaired
A
- Hypernasal on non-nasals
- Hyponasal on nasals
- Abnormal Phrasing/flow/rhythm
- Monotone speech
- Improper stress patterns
- Restricted pitch range
- Inappropriate high pitch
- Fast/Slow ROS
- Inappropriate pauses
- Inefficient breathing
- Voice quality deviations - hoarseness & harshness
