Ch. 10 - Hearing and Language (FINAL)

Question 1

sound waves: frequency

Answer 1

PITCH of a sound
represents the number of cycles completed in x amount of time
humans: 20-20,000Hz

Question 2

sound waves: amplitude

Answer 2

LOUDNESS of a sound
represents strength of auditory stimulus
- loud: over 70db
- soft: under 20db

Question 3

sound waves: complexity

Answer 3

COMPLEXITY of a sound
mixes of frequencies
- pure tone: single frequency/simple
- complex tone: mixture (most sounds!)

Question 4

air pressure waves: compression and rarefaction

Answer 4

compression: squeezing of air (high density)
rarefaction: freeing of air (low density)

Question 5

anatomy of auditory system (ear)

Answer 5

outer ear
- pinna
- external ear canal

middle ear
- ossicles (malleus/hammer, incup/anvil, stapes/stirrup)

inner ear
- semi-circular canals
- cochlea
- auditory nerve

Question 6

cochlea: cilia anatomy

Answer 6

cilia (hair) on top of nerve fibres
bending of cilia leads to graded potentials sent through auditory nerve

bending towards tall: depolarization
bending towards short: hyperpolarization

Question 7

basilar membrane: anatomy

Answer 7

unrolled cochlea!

BASE: posterior
- high frequency
- narrow and thick

APEX: anterior
- low frequency
- wide and thin

Question 8

auditory cortex pathway

Answer 8

1. auditory nerve
2. medulla (ventral cochlear nucleus - L)
3. inferior colliculus (tectum - R)
4. medial geniculate nucleus
5. A1

Question 9

primary auditory cortex (heschl’s gyrus): 2 areas

Answer 9

wernicke’s area
- posterior speech zone
- mental dictionary
- language comprehension

broca’s area
- anterior speech zone
- produces speech
- motor programming

Question 10

aphasia (language impairment) of the 2 areas

Answer 10

wernicke’s area
- can speak but it’s jibberish
- can’t understand or produce langauge

broca’s area
- inability to speak fluently
- can understand but not produce
- distressing