1. Hearing

2. Audition Begins with sound entering ear
Sound: physical energy caused by vibrating objects.
Vibrations produce movement of air molecules (sound waves)
Moving one’s head aids in detecting sound source

3. Audition

4. Characteristics of Sound
Loudness
Pitch
Complexity

5. Characteristics of Sound
Loudness: dimension of hearing related to the intensity of a wave’s pressure
Corresponds with amplitude, or maximum height, of a sound wave
The more energy contained in the sound wave, the higher it is
Measured in decibels

7. Noise & Toys

8. Characteristics of Sound
Pitch: Frequency of the sound wave
Frequency: how rapidly the air vibrates
Number of times per second the wave cycles from peak to peaks
The greater the number of cycles, the higher the pitch
Measured in hertz

9. Pitch
Wavelength

10. Highest Frequency? Loudest? Highest Amplitude? Highest Pitch?B. C.

11. Characteristics of Sound
Complexity: Distance of the range of frequencies
Wavelengths
Usually what we hear is a combination of several subwaves with different frequencies
This is what distinguishes one sound from another
Same note played on a flute will sound different when played on a clarinet

12. Anatomy of the Ear
Pinna: external visible flap of skin and cartilage

13. Anatomy of the Ear Auditory Canal: part of outer ear along with pinna
Leads to eardrum

14. Anatomy of the Ear Eardrum: separates outer ear from middle ear
Vibrates with reception of sound

15. Ear Wax
Produced by glands in outer ear to protect inner ear from infection
Sticky substance prevents dust, dirt, and bags from getting in

16. Be Careful! Q-Tips can be dangerous! Can push wax further into eardrum
Can even perforate, or break, your eardrum

17. YOLO.

18. What Do Doctors Suggest?
“Just leave it alone,” says Dr. Andrew Chang, an ear, nose, and throat specialist.
Wax slowly moves up and out of the ears on its own, dries up, and flakes off or washes away when you shampoo your hair.
My name’s Dr. Chang, and I’m unabashedly disgusting.

19. Anatomy of the Ear Ossicles: three bones in middle ear
Hammer
Anvil
Stirrup
Smallest bones in the body
Transmit sound vibrations to the cochlea
Eardrum
Auditory Canal

20. Ossicle Bones

21. Anatomy of the Ear Cochlea: part of inner ear
Contains fluid & receptors

22. Inside the Cochlea Contains 25,000 tiny hair cells known as cilia
Transmits sound frequencies into electrical impulses

23. How Do I Remember All of These?
Please
Exit
Our
Cool
Crowd
Pinna
Eardrum
Ossicle Bones
Cochlea
Cilia

24. How Does Sound Move Through the Ear?

25. Types of Deafness

26. Conduction Deafness
Caused by the failure of the three tiny bones inside the middle ear to pass along sound waves to the inner ear or the failure of the eardrum to vibrate in response to sound waves
Possible cause is a build-up of fluid
Hearing aids
Normal hearing may return.

27. Sensory-Neural Deafness
Damage to the inner ear. Most often caused by loss of hair cells that will not regenerate.
Damage to the auditory nerve.
Cochlear implants can help patients with this form of deafness.

28. Stimulation Deafness Exposure to very loud sounds
Prolonged exposure to 85 dB can cause stimulation loss.
Ringing sound can mean hair cells have been damaged