Chapter 11 Hearing

Question 1

What advantage does hearing have over vision

Answer 1

-Barriers aren’t an issue
-Ears are always on

Question 2

What is the physical definition of sound?


Answer 2

Pressure changes in the air or other mediums (most sound starts in air)

Question 3

What is the perceptual definition of sound?

Answer 3

The experience we have when we hear (more overlap)

Question 4

What does amplitude refer to in sound waves?


Answer 4

Difference in pressure between high and low wave peaks (height)

Question 5

Decibel (dB)

Answer 5

-Is used to measure loudness (perception)
-Logarithmic scale
-How physical energy interacts w/ perception

Question 6

The decibel scale relates the amplitude of the stimulus…?

Answer 6

With the psychological experience of loudness

Question 7

Decible scale noise examples

Answer 7

Quite: breathing, whisper, fridge
Medium: car, truck, hair dryer
Loud: Siren, jet, fireworks

Question 8

Frequency

Answer 8

-The number of cycles within a given period (increasing peaks)
-Related to perception of pitch

Question 9

How is frequency measured?

Answer 9

In Hertz (Hz), 1 is once cycle per second

Question 10

Tone height

Answer 10

When frequency is increased, the pitch increases

Question 11

Hearing/Voicing frequencies across species

Answer 11

Low frequency- elephant, dog
High frequency- bat, cat

Question 12

Pure Tone

Answer 12

-Tone with a sinusoidal wave form
-Sounds like a beep (smoke detector)
-Good for emergency

Question 13

Complex Tone

Answer 13

-The summation of many pure tones
-Most sounds in the world

Question 14

Fundamental frequency

Answer 14

Repetition rate called the first harmonic (multiples of the same #)

Question 15

Periodic Complex tones consist of….?

Answer 15

Several pure tones called harmonics

Question 16

Additive synthesis

Answer 16

Adding harmonics to create complex sounds

Question 17

Frequency Spectrum

Answer 17

Display of harmonics of a complex sound (ways we visualize this)

Question 18

Spectrograms

Answer 18

Useful for representing complex waveforms like speech and change overtime

Question 19

Human hearing range

Answer 19

20 to 20,000 Hz

Question 20

Audibility Curve

Answer 20

-Shows threshold of hearing in relation to frequency
-Humans are most sensitive to 2,000 to 4,000 Hz

Question 21

Auditory Response Area

Answer 21

-Falls between the audibility curve and threshold for feeling
-Range of response for human audition

Question 22

Equal loudness curve

Answer 22

Determined by using a standard 1,000 Hz tone

Question 23

Pitch

Answer 23

Perceptual quality we describe as high and low

Question 24

Attack of tones

Answer 24

Buildup of sound at the beginning of a tone

Question 25

Decay of tones

Answer 25

Decrease in sound at the end of time

Question 26

Outer ear

Answer 26

Pinna and auditory canal

Question 27

Pinna

Answer 27

Helps with sound location

Question 28

What are the two middle ear membranes?

Answer 28

1.) Tympanic membrane/eardrum 2.) Oval window- leads to cochlea

Question 29

Ossicles

Answer 29

Bones that amplify and transfer vibrations from air to fluid

Question 30

Cochlear partition extends from....?

Answer 30

The base (stapes) to the apex (far end)

Question 31

Organ of Corti is contained by...?

Answer 31

Cochlear partition

Question 32

Inner Hair Cells

Answer 32

All information about sound waves to brain (3,500)

Question 33

Bekesy's Place Theory of Hearing

Answer 33

Frequency of sound is indicated by the place on the organ corti with the highest firing rate

Question 34

Bekesy determined this in 2 ways

Answer 34

1.)Direct observation of basilar membrane in cadavers 2.)Cochlea model made from physical properties of basilar membrane

Question 35

High Pitch

Answer 35

Proximal end of cochlea (base near oval window)

Question 36

Low Pitch

Answer 36

Distal end of cochlea (apex near center of coil

Question 37

Auditory Nerve

Answer 37

Carries signals from cochlea to brain stem (both hemispheres)

Question 38

Cochlear Nucleus

Answer 38

First brain stem nucleus where auditory nerve fibers synapse

Question 39

Superior Olive

Answer 39

Early brain stem region in the auditory pathway where inputs from both ears converge

Question 40

Inferior Colliculus

Answer 40

Midbrain nucleus in auditory pathway (orienting reflexes)

Question 41

Primary Auditory Cortex

Answer 41

In temporal lobe

Question 42

Tinnitus

Answer 42

-Ringing in the ear -Fills your head and no one else hears -High pitched like ringing, clicking, pulsing, humming, or rushing

Question 43

Hearing Loss 1 (Presbycusis)

Answer 43

-Greatest loss at high frequencies -Affects males -Caused by damaging noises or drugs

Question 44

Hearing Loss 1 (Noise-induced hearing loss)

Answer 44

-Loud noise can damage organ of Corti -OSHA standards set noise levels at work -Leisure noise can cause hearing loss

Question 45

Hearing Loss 3 (Sensorineural Hearing Loss)

Answer 45

-Most common and serious auditory impairment -Defects in cochlea/auditory nerve when hair cells are injured

Question 46

Cochlear Implants

Answer 46

Electrodes are inserted into the cochlea to electrically stimulated auditory nerve fibers

Question 47

Hearing Loss Over Lifespan

Answer 47

-Natural consequence of aging -Young people: 20-20,000 Hz -College:20-15,000 Hz -Earliest hearing aids were horns, now they are electronic