Perception Flashcards
What can sound be defined as?
It can be defined as waves of changing pressure travelling through air
What is a pure tone?
It has an amplitude and a frequency
In a pure tone, what is equivalent to frequency?
Perceived pitch
What are natural sounds?
Consist of pure tones of many frequencies added together e.g., voice
What is an amplitude?
the maximum air pressure in each cycle
What is frequency?
the number of cycles of changing air pressure per second
What do we measure frequency in?
We measure it as hertz
What are the two physical properties of sound?
frequency and amplitude
What happens when amplitude is increased 10 times?
Loudness increases approximately 4 times
Where does sound come along?
Sound comes along the auditory canal to the ear drum
What does sound influence?
Sound influences the eardrum
What is the eardrum connected to?
It is connected to three small bones:
malleus, incus &stapes
What does the cochlea have connections to?
Connected to the auditory nerve
If you were to unroll the cochlea, what would you see?
the basilar membrane
What does the basilar membrane have?
The basilar membrane has a lot of mini hairs on it
What does each part of the basilar membrane vibrate to?
It vibrates to a particular frequency
What does the basilar membrane do?
It bends and contorts dependent upon the frequency of the sound
What does the basilar membrane hairs do?
They fire depending upon the frequency and amplitude
What is the basilar membrane at the base also known as?
It is also known as oval window
What does the basilar membrane at the base respond to?
It responds to high frequency sounds
What does the basilar membrane at the tip respond to?
It responds to low frequency sounds
What is the basilar membrane at the tip also known as?
It is also known as the apex
What does the basilar membrane in the middle respond to?
It responds to medium frequency sounds
What are hair cells?
They are mechanoreceptors; they are sensory instruments that allow us to perceive the physical properties of sound as perceptual ones
What do hair cells send?
They send electrical signals to the brain through the auditory nerve
What does each hair cell signal?
Each hair signals the amplitude of one narrow range of frequencies in the sound
What is the perception of loudness based on?
The perception of loudness is based on the firing rate of the hair cells
What are the 3 physical dimensions of sound?
- frequency
- amplitude
- complexity
What does frequency correspond to?
Corresponds to our perception of pitch