1. Do Now Begin copying/drawing this on blank side of paper
Coloring can help one distinguish the different parts

2. Unit 4: Sensation & Perception
Hearing

3. Audition It all begins with sound. Listen to this!
(whistle)
Sound is mechanical energy typically caused by vibrating objects
Vibrations produce movement of air molecules called sound waves

4. Measuring Sound Measured in decibels Characteristics if sound
Frequency – number of complete wavelengths … determine pitch
Pitch – the experienced highness or lowness of sound
Amplitude (loudness/volume)
Complexity (timbre/quality)

5. Structure of Ear Outer ear Auditory canal Eardrum Middle ear Hammer
Anvil
Stirrup
Oval window
Inner ear
Cochlea
Basilar membrane
Auditory nerve
Temporal lobe
Auditory cortex

6. Processing Sound
how hearing works

7. Auditory Theories Place Theory Frequency Theory Volley Theory
HSS Economics Quarter 1
Auditory Theories
Place Theory
differences in pitch result from stimulation of different areas of the basilar membrane (in the cochlea)
Frequency Theory
AKA – Temporal Theory
differences in pitch are due to rate of neural impulses traveling up the auditory nerve
Volley Theory
surmises that the neurons fire in sequence as a rhythmic volley at higher frequencies.
Like going back and forth
Allows us to hear things about 1000 waves (the upper 1/3 of a piano) because its combining frequencies
Theories of Hearing
Which best explains why we hear?

8. Noise Pollution Lengthy exposure of 90 db causes permanent damage
110 db for 30 minutes causes permanent damage
120 db for 5 minutes causes permanent damage

9. Deafness Possible Causes Conductive deafness Perceptive deafness
Tumor, skull injury, birth defect, poison, rubella
Conductive deafness
Lack of conduction the to basilar membrane (cochlea)
Perceptive deafness
Nerve damage

10. Today Review Begin HW if time HW = Other Senses (Due Mon. 10/22)
Sensation & perception
Structure of eye
Structure of ear
Begin HW if time
HW = Other Senses (Due Mon. 10/22)