Sensation and Perception:

  • Do Now - If you had to lose one sense, what would it be and why?

    • Sight, because sight is kind of superficial. People like aesthetic things, and are obsessed with beauty. If we couldn't see, we wouldn't be so prejudice, and equality could be achieved. When I think of senses, I think of the song "Luv (Sic) Pt. 1," and in one of the verses, the artist said "Let the blind see beyond harmony," which refers to the blind people seeing more than those who can actually see. They can see "beyond harmony".

This activity explores how we hear and how the physical nature of the sound wave determines the qualityof the sound experience.

The Auditory System

• What are the four tasks of the auditory system?
1. Pick up stimulus energy from the world around us.
2.Change that energy into a pattern of neural impulses
3.Carry those impulses to the proper locations in the brain.
4. Process the information contained in the pattern of impulses that the stimulus can be identifed.

Structure of the Ear
• What are the three main regions of the ear and their associated parts?
1. Outer Ear - pinna, ear canal, eardrum
2. Middle Ear - stirrup, hammer, anvil, eardrum
3. Inner Ear - cochlea, auditory nerve, semicircular canals

The Sound Wave
• How are sound waves like ocean waves? - The ear must detect changes in the air pressure surrounding the eardrum
• What are the three aspects of sound waves?
1. frequency
2. amplitude
3. waveform

Frequency: The Rate of Vibration
• Which type of tuning fork would vibrate faster—a small, short one or a large, long one? Why?
Small or short objects vibrate faster than similar objects that are larger or longer. If the longer fork produces a sound wave that looks like the top wave, then the shorter fork should produce a sound wave like the bottom wave.

• How is frequency measured and calculated?
- Measured by counting the number of times the wave goes up and down each second.

Frequency, Amplitude, and Waveform
• The frequency of a sound wave determines the pitch_ of the sound we perceive.

• The amplitude of a sound wave determines the loudness_ of the sound we perceive.

• The waveform of a sound wave determines the quality (timbre)___ of the sound we perceive.

Hearing Sounds
• What happens inside the cochlea?
-When the vibration passes through the middle ear to the cochlea, the oval window moves in and out, causing the pressure in the outer vchamber to increase and decrease in a rapid sequence. The alternating high and low pressure in the outer chamber produces ripples in the basilar membrane, and bends the hair cells, causing them to generate neural impulses.