Week 9.1 Auditory Percep Flashcards
what is sound
waves of changing pressure travelling through air
a pure tone has
an amplitude
a frequency
amplitude is
maximum air pressure in each cycle
frequency is
number of cycles of changing air pressure per second
in pure tone, perceived pitch is equivalent to
frequency
natural sounds consist of
pure tones of many frequencies added together
perceived loudness is related to
amplitude
increasing amplitude 10x causes loudness to
increase approx 4x
auditory transduction occurs in
cochlea
basilar membrane
hair cells
hair cells are X that transduce X that send X
mechanoreceptors
transduce vibration of the basilar membrane
send elec signals to brain through auditory nerve
place coding of sound frequency in the cochlea
each part of basilar membrane vibrates to particular frequency
frequency = highest at base (oval window)
lowest at tip (apex) of cochlea
- each hair cell signals amplitude of one range of frequencies in the sound
perception of loudness is based on
firing rate of hair cells
max range of frequencies a person can hear
20Hz - 20kHz
3 physical dimensions of sound
frequency
amplitude
complexity
3 dimensions of sound determine what we hear
pitch
loudness
timbre
LCD
frequencies in sound = integer multiples of a single number = least common denominator (LCD) of component frequencies
harmonic structure
complex sounds where all components share an integer LCD
fundamental frequency
the lowest frequency component of the sound
