hearing part 3

Question 1

place theory of pitch perception

Answer 1

determines location of greatest movement along basilar membrane
determines which auditory nerves have peak activity
determines perceived pitch

Question 2

what are the issues of place theory

Answer 2

dont account for missing fundamentals:
- can have sound without a peak at 100Hz but still perceive pitch
amplitude modulation:
- fluctuating amplitude of sound at a freqeuncy changes pitch perception despite same frequency of sound

Question 3

temporal theory of pitch perception

Answer 3

time based information about which and WHEN auditory nerve fires

• timing or repetition rate of a sound is available even when fundamental is missing and with amplitude modulation
• leads to phase locking

Question 4

place theory VS temporal theory

Answer 4

place: pitch perception depends on which auditory nerves are active
- place along basilar membrane
temporal theory: pitch perception depends on timing of when auditory nerves are active
- temporal pattern of activation

Question 5

which theory is correct: place or temporal

Answer 5

most likely both matter

Question 6

auditory pathway

Answer 6

• auditory nerve
• cochlear nuclei
• Superior Olivary Nucleus (pons)
• Inferior Colliculus (midbrain)
• Medial Geniculate nucleus (thalamus)
  primary auditory cortex
  SONIC MG

Question 7

auditory cortex

Answer 7

core: A1- tonotopic map
belt - secondary
parabelt- tertiary

Question 8

pitch neurons

Answer 8

in the auditory cortex of marmoset monkey

• responds to groups of harmonics that represent the same pitch
• same repetition rate
• frequency selective and does not respond to individual harmonics

Question 9

tonotopic map in pitch neurons

Answer 9

small dots - frequencies of pure tones

large squares- pitch of complex tones with missing fundamental

Question 10

cochlear implant

Answer 10

• address hearing loss due to damaged or nonworking hair
• existing problem with conversion of sound into info
• majority of deaf children who receive one before 18 months had language skills similar to hearing

Question 11

5 components of cochlear implants

Answer 11

external:
1. microphone: transduce sound to electricity
2. processor: analyzes sound into frequency bands
3. transmitter: sends signals and power
Internal:
4. receiver: recieves signals and power
5. electrodes: stimulate different auditory nerves along cochlea