Download PsychSim 5: THE AUDITORY SYSTEM Name: Kiet

PsychSim 5: THE AUDITORY SYSTEM
Name: Kiet Luong____________________________ Section: 6_________________
Date: ____November 7, 2011_____________________________
This activity explores how we hear and how the physical nature of the sound wave
determines the quality of 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 so that the stimulus
can be identified.
Structure of the Ear
What are the three main regions of the ear and their associated parts?
1. Outer Ear
2. Middle Ear
3. Inner Ear
The Sound Wave
How are sound waves like ocean waves?
The wave is drawn as a set of concentric circles. When it is drawn it resembles an
ocean wave with crests (peaks_ and troughs (valleys). The crests is the regions of
high pressure and the troughs, low pressure.
What are the three aspects of sound waves?
1. Frequency
2
amplitude
2. Wave form
Frequency: The Rate of Vibration
Which type of tuning fork would vibrate faster—a small, short one or a large, long
one? Why?
Short fork produces wave with more peaks per unit of time. So it has a higher
frequency
How is frequency measured and calculated?
You can calculate the frequency for the top wave in peaker per second (10 msec equals
1/100 sec)
Frequency, Amplitude, and Waveform
The frequency of a sound wave determines the number of times the wave goes up and
down each second_____pitch___________ of the sound we perceive.
The amplitude of a sound wave determines the _units of pressure called decibels,
and controls the perceived loudness of the sound we perceive.
The waveform of a sound wave determines the 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 chamber to increases and decrease in a rapid sequence.