auz

Question 1

What is loudness?

Answer 1

Amplitude of compression of molecules

Question 2

What is pitch?

Answer 2

Wavelength/frequency of sound waves

Question 3

What is amplitude of soundwaves?

Answer 3

Is its intensity
Generally amplitude = greater loudness

Question 4

What is frequency?

Answer 4

The number of compressions per second, in Hz
Higher frequency = higher pitch

Question 5

What is complexity?

Answer 5

Timbre
Different instruments have different harmonics.

Question 6

What is Fechner’s law?

Answer 6

There is a logarithmic relationship between stimulus intensity and subjective intensity.

Question 7

What is sound amplitude measured in?

Answer 7

Decibels.

Question 8

What are the 3 parts of the ear?

Answer 8

Outer
Middle
Inner

Question 9

What is the outer ear?

Answer 9

The pinna (auricle) and the auditory canal amplify and filter sound reaching the ear

The notch of the pinna filters sounds in mid-range frequencies in a directionally dependent manner - assists sound localisation

Rabbits’ movable pinna allow even better location of sound

Question 10

What is the middle ear?

Answer 10

After moving though canal, sound waves strike the tympanic membrane
Membrane then vibrates at same frequency as wave that strikes it
Membrane is connected to the ossicles

The ossicles:
- comprise the malleus, incus, and stapes (hammer, anvil and stirrup)
- act to amplify vibrations in the air of the outer/middle ear for better transmission to fluid of the inner ear
- transmit vibrations to the oval window (in the inner ear)

The tensor tympani muscle (hooked to the ossicles) protects the inner ear against loud noise

Question 11

What is the inner ear?

Answer 11

Snail shaped contains 3 long fluid-filled tunnels:
- scala vestibuli
- scala media
- scala tympani

Oval window leads to scala vestibuli

Sound waves:
- set in motion fluid in cochlea starting from scala vestibuli
- travel the fluid of the inner ear, trasmitting vibrations to the organ of corti

Organ of corti:
- located in the scala media
- includes 3 rows of outer hair cells and has one row of inner hair cells

Hair cells in the organ of corti:
- auditory receptors lying between basilar and tectorial membrane
- displaced by vibrations of the fluid in cochlea
- their displacements lead to the opening of ion channels in their membranes
- consequent excitation of cells of the auditory nerve

Question 12

How do neural signals pass in the auditory brain?

Answer 12

From cochlea along the cochlear nerve
To the ipsilateral cochlear nucleus (in the brain stem)
To the superior olivary nucleus
Up to the thalamus and auditory cortex

Question 13

What is the superior olivary complex for?

Answer 13

Important structure for sound localisation

Question 14

Auditory cortices?

Answer 14

Tonotopy and amplitude selectivity are a
functional feature of A1

• Once auditory signals reach auditory cortex they enter conscious awareness
• damage of Auditory cortex leads to loss of aural awareness