overview of the ear

Question 1

Functions (3)

Answer 1

1. Hearing
2. Sound Localisation
3. Balance maintance

Question 2

process of sound wave movement: external -> brain

Answer 2

1. Auricle (collects sound)
2. External Acoustic Meatus (directs sound)
3. Tympanic Membrane (vibrates b/c of sound waves)
4. Ossicles (move due to vibrations)
5. Cochlea (movement of ossicles causes ‘waves’ in fluid)
6. Nerve Cells lining cochlea sense the waves in fluid stimulating APs
7. Auditory Nerve (transports APs)
8. Auditory Cortex

Question 3

how does sound localisation occur?

Answer 3

1. Time Difference b/w signals from L + R

2. Intensitity Difference b/w signals from L+R

Question 4

what is balance are result of? (3)

Answer 4

inputs, auditory factors, CNS responses

Question 5

Process of balance

Answer 5

Inputs->Integration->Outputs

Question 6

Inputs of balance system (3)

Answer 6

vestiular system (in inner ear), vision, proprioceptual (somatic sensory info)

Question 7

what does ‘reduency’ mean in terms of inputs of balance system

Answer 7

for balance to be maintained only 2/3 of the inputs are required by the brain

Question 8

Integration of balance system (2)

Answer 8

brain stem + cerebellum

Question 9

Outputs of balance system

Answer 9

motor APs from brain activate muscles and joints to respond to movement and maintain balance