Inter-Aural Time Differences: if a sound comes from the
right, it will hit the right ear before the left ear
-works better with low frequencies because there is a
bigger time difference between the top and bottom of the
-high frequencies have smaller distances between
Inter-Aural Level Differences: works better for high
frequencies, Acoustic Shadow. high frequency sound
waves wrap right around the head, low acoustic
shadow, whereas low frequency waves will get blocked by
-if something is equally loud in both ears (sound arriving at
same time), the sound is likely coming from in front or
behind you. you can know for sure by turning your ear in
both directions (front, back)
Elevation (^, v): Cone of confusion: same cue can be
perceived from anywhere inside the cone shape
emanating from the ear. the cone is a function of the
shape of the pinnae, because the curves bounce sound in
Spectral Cues: the farther away the sound, the less sound
will reach the ears.
-how can you tell the difference from a big sound far
away, and a small sound very close?
-how do we know the sound is big or small?
-how do we know if it is far away or close?
-fundamental frequency: tone (note) that you hear,
Harmonics are multiples of the fundamental
-Complex Tone: will have fundamental, and harmonics
(most sounds). the high frequencies tend to dissipate
before the low frequencies, do not travel as well
-can use the harmonics as an indicator of how far
away the sound is (farther distances you will loose more
of the high harmonics) <-- how rich sound is with
harmonics is an indicator of how far away it is
Olfaction: Chemical Sense (Chapter 15, 355-366)
1. Importance: humans do not have the best sense of
olfaction compared to other species.
-important aesthetically, linked to feelings of pleasure
-olfaction is very closely linked to emotion
-important for protection (e.g, smelling a fire, eating
rotting food, smelling other organisms)
-important for communication, pheromones