1. You better be listening…
Auditory Senses
You better be listening…

2. Sound Waves Height of wave Amplitude Determines how loud Wavelength
Determines pitch
Peak to peak
High frequency, waves packed = high pitch
Low frequency, loose waves = low pitch

3. How we hear: Outer Ear The pinna channels sound waves into the ear
Naturally blocks out ‘background noise’
Sound waves travel through the auditory canal and vibrates the ear drum

4. How we hear: Middle Ear The ear drum vibrates and pulses your ossicles

5. Cochlea Ossicles vibrate the cochlea Transduction occurs
When hair cells move in cochlea, it
turns sound waves
(vibrations) into
neural impulses
Video of Natural Earing (1:05)

6. Major Divisions of the Ear
Outer Ear
acts as a funnel to direct sound waves towards inner structures
Middle Ear
consists of three small bones (or ossicles) that amplify the sound
Inner Ear
contains the cochlea that actually transduces sound into neural response

7. Hearing Loss Can’t regenerate hair growth Conduction Hearing Loss
Physical damage to ear drum or ossicles
Nerve Hearing Loss
2 ways to damage cochlear hairs
Can’t regenerate hair growth

8. Sound Location
Figuring out where sound is coming from
seconds

9. How we do perceive loud?
number of hair cells that move in the cochlea

10. How do we perceive pitch?
Place theory
Where the hairs are located correspond to pitch
High pitch; sensitive near the beginning
Low pitch; sensitive towards the end
Frequency theory
number of impulses fired from the auditory nerve