Quiz 1: Pyschophysics and Audition Study Guide

Question 1

What are the 3 main psychophysical methods to determine thresholds?

Answer 1

-method of limits
-method of adjustment
-method of constant stimuli

Question 2

Method of limits

Answer 2

a psychophysical method in which particular dimension of a stimulus, or the difference between two stimuli, is varied incrementally until the participant responds differently

Question 3

Method of adjustment

Answer 3

the method of limits for which the subject controls the change in the stimulus
-attempts to improve accuracy with subject-controlled change
-LEAST PRECISE of the 3 methods because the subject can unreliably adjust the stimulus to the same threshold across trials

Question 4

Method of constant stimuli

Answer 4

a psychophysical method in which many stimuli, ranging from rarely to almost perceivable, are presented one at a time at random

Question 5

Who is Gustav Fechner?

Answer 5

Creator of psychophysics- a way to test a person’s perception of a stimulus
Made the formula S= k log R

Question 6

What is the difference between the logarithmic scale and the linear scale?

Answer 6

Logarithmic scale for psychophysics
S= k log R
Sensory receptor- sensitive to small stimuli but activation maxes out eventually
Increases by a factor making large numbers appear smaller
Better representation of values with a high range without sacrificing resolution at the low end

Linear scale
Y-axis increases by addition
(i.e. you perceive a wide range of physical stimuli)

Question 7

What are the two qualities of sound waves?

Answer 7

Amplitude and Frequency

Question 8

Amplitude

Answer 8

Loudness or intensity
Amount of change in pressure in a sound wave
Measured in dB

Question 9

Frequency

Answer 9

Pitch
Rate of recurrence of oscillations/ vibrations in a sound wave
Measured in Hz

Question 10

Middle ear and the in-between (before the inner ear)

Answer 10

Ossicles
oval window/ round window

Question 11

Structure of the Outer ear and the in-between (before middle ear)

Answer 11

Pinna, Ear canal
Tympanic membrane

Question 12

Structure of the Inner ear

Answer 12

Cochlea
Vestibular system (semicircular canals)
Organ of corti

Question 13

What does tonotopic mean?

Answer 13

= the organization of neurons according to their characteristic frequency

The primary auditory cortex contains a topographic map of the cochlear frequency spectrum

Question 13

Pathway of sound waves from physical vibration to electrical signals in the brain

Answer 13

Pinna>Ear canal>Tympanic membrane>Ossicles>oval window>cochlea>round window>vestibular canal>middle canal>Organ of Corti>hair cells>auditory nerves>cochlear nucleus>superior olives>lateral lemniscus>inferior colliculus>medial geniculate nucleus>primary auditory cortex

Question 14

How does the tonotopic organization relate to the cochlea and the auditory cortex?

Answer 14

All structures in the auditory system show an organizational pattern where neurons are aligned respective to the frequencies that they are most sensitive

Question 15

What happens inside the cochlea? Specifically how does transduction occur in the cochlea?

Answer 15

1- Ossicles hit the oval window with pressure
2-Oval window moves
3-Traveling waves of the fluid inside the cochlea, flowing down the vestibular canal
4-Vestibular canal bulges, placing pressure on middle canal
5-Middle canal displaces the cochlear partition
-depends on frequency (High= near oval, low= near round)

Question 16

What are the different types of deafness?

Answer 16

Sensorineural hearing loss
Conductive hearing loss
Mixed hearing loss
Bilateral hearing loss
Unilateral hearing loss

Question 17

Sensorineural hearing loss

Answer 17

Occurs as a result of damage to the auditory nerve or when hair cells are damaged
-most common type of hearing loss

Question 18

Conductive hearing loss

Answer 18

Occurs when the ossicles become unable to convey vibrations to the oval window

Question 19

Mixed hearing loss

Answer 19

Occurs when you have both sensorineural and conductive issuesBilat

Question 20

Bilateral hearing loss

Answer 20

Hearing loss in both ears

Question 21

Unilateral hearing loss

Answer 21

Hearing loss in one ear

Question 22

Typical human hearing range and different ways it is measured

Answer 22

20-20,000 Hz
Measured:
3 psychophysical methods
Audiometer

Question 23

Habituation

Answer 23

Participant hesitates to switch his/her response
Participant continues responding Y or N too long
i.e. they “get used to” responding a certain way
-they forget, zone out, tune out

Question 24

Expectation

Answer 24

Participant expects the stimulus to increase (or decrease) and thinks that the stimulus should now be detectable and thus responds it did increase or decrease even if the stimulus is not yet at threshold
i.e. jumping the gun

Question 25

Interaural time delay

Answer 25

= the difference in time between a sound arriving at one ear compared to the other
-varies for different sound source positions
-Medial superior olive
-Excitatory input from the two ears arrives coincidentally at one of an array of cells inn the MSO

Question 26

Interaural level difference

Answer 26

= the difference in intensity between a sound arriving at one ear compared to the other
-Lateral superior olive
-Excitatory input from ipsilateral ear and inhibitory input from the contralateral ear (sound from that side will be stronger)

Question 27

Know the auditory pathways from the vestibucochlear nerve through the auditory cortex

Answer 27

ECO-LIMA
Ear (pinna, etc.)
Cochlear nucleus
Superior olive
Lateral Lemniscus
Inferior Colliculus
Medial Geniculate Nucleus
Primary auditory cortex

Question 28

Cochlear nucleus

Answer 28

=the first processing stage with many different types of specialized cells

Question 29

Superior olive: Medial and Lateral

Answer 29

• important role in the localization of sound
  -projections from cochlear nucleus to superior olive also cross over to the opposite side of the brain
  Medial Superior Olives
  -Interaural time differences primarily occur
  Lateral Superior Olives
  -hold neurons sensitive to intensity differences
  -Interaural Level Difference

Question 30

Lateral Lemniscus (Fiber tract)

Answer 30

-contains axons from cochlear nucleus, superior olive, and the nucleus of the lateral lemniscus
-projects to the inferior colliculus

Question 31

Inferior Colliculus

Answer 31

-Signal integration, frequency recognition, and pitch discrimination
-Second level of processing

Question 32

Medial Geniculate Nucleus

Answer 32

-Part of the Thalamus that relays auditory signals to the cortex

Question 33

Primary Auditory Cortex

Answer 33

-processing of tones; tonotopic organization