Auditory Perception Flashcards
Vision perception is good at ____ information while auditory perception is good at ___ information
Vision –> spatial
Auditory –> temporal (time of event)
What kinds of information can be taken from sound?
spatial location (direction, distance) , semantic, emotion (music), substance
What is the Physical Stimulus for Sound?
the compression and spreading apart of air molecules (or water, etc)
1) This compression and rarefaction (spreading) is caused by any movement or vibrational event in a medium, such as air or water.
2) The disturbance in the medium spreads as a wave outward from the disturbance.
Concentric waves
as sound moves further away from the source, the amplitude becomes lower
Speed of sound in air
330 m/sec (quite fast)
Fourier transformation
decomposing a complex waveform into the summation of its sine wave components
- how scientists describe sound
- unique to each signal; can only be described one way
Sounds are __ dimensional signals
1 dimensional
Fundamental frequency
- the lowest frequency in a sound
- higher frequencies (harmonics) are always integer multiples of this
e. g.
- fundamental frequency is 5 hertz
- harmonics can be 10 hertz, 15, hertz, 20 hertz, etc
Harmonics
all frequencies higher than the fundamental frequency in a sound fourier transformation
*always a multiple integer of the fundamental frequency
Are sine waves commonly heard in the world?
NO, not many vibrations in the world are so pure
* most sounds are a combination of sine waves, thus the fourier transformation
Outer ear structures
pinna and ear canal
Middle ear structures
three ossicles
!! ADD IN LATER !!
Task of the middle ear
amplify sounds
!! ADD IN LATER !!
Inner ear structures
Three canals:
- cochlea
Nerves leaving the cochlea form the auditory nerve, and then the vestibular nerve
Transduction
translation of the mechanical energy (vibration) received by the cochlea structures into a neural signal
