Audition Flashcards
Which stimulus is used for audition?
Sound waves
What are sound waves?
Pressure waves travelling through any medium that will allow their conduction
What are the two key characteristics of sound waves?
Frequency
Amplitude
What is frequency?
The number of sound waves (or cycles) per second
What is frequency measured in?
Hertz
What does frequency determine?
The pitch of a sound - high frequencies produce high-pitched sounds and low frequencies produce low-pitched sounds
What is the full range of frequencies than humans can detect?
20 to 20,000 Hz
What is amplitude?
The vertical size of sound waves
What is amplitude measured in?
Decibels - the measure of the physical pressure occurring at the eardrum
What does amplitude determine?
The loudness of a sound - smaller waves are quieter, larger sound waves are louder
What is considered a safe level in decibels?
85 and below
What is the minimum threshold of hearing?
0 decibels
Give an example of a sound at 0 decibels
A fly at 3m away
Give an example of a sound at 50 decibels
A busy restaurant
What is the level of decibels that can cause damage with prolonged exposure?
90 decibels
Give an example of a sound at 90 decibels
A kitchen blender
What is the human pain threshold for hearing?
130 decibels
Give an example of a sound at 130 decibels
A loud metal workshop
What is the threshold for potential immediate damage to hearing?
140 decibels
Give an example of a sound at 140 decibels
A jet fighter taking off 25m away
What does the outer ear consist of?
Pinnae
Auditory canal
Eardrum
What are pinnae?
The visible parts of the ears which reside outside of the head
What is the function of the pinnae?
To collect sound and help localise where sounds are coming from
Which frequencies are the pinnae particularly good at collecting?
Frequencies within the human speech range
What happens once a sound is detected by the pinnae?
It is funnelled, amplified and directed into the auditory canal
What happens after sounds reach the auditory canal?
They travel to the eardrum, which vibrates in response