Auditory system

Was not able to attend the lecture but the lecture slides were quite useful. I found the sound localization concept quite interesting in this weeks lecture.

On average people can localize sounds that come from in from of them better than the sounds that originate from behind them or from the sides. The location of sound is not detected by the sound receptors unlike the eye.

The three cues used for sound localization are :

Interaural time difference – It is the difference between the time the sound reaches the two ears. If the source of sound is in the front, the ITD is zero. If the source is on the side, the ITD is high. This cue is used for determining the location of the sound in the horizontal plane.

Interaural level difference – It is the difference in sound pressure level reaching the two ears. Reduction in sound level occurs for high frequency sounds for the far ear. The head casts an acoustic shadow.It is best for high frequency sounds because low frequency sounds are not attenuated much by the head. This cue is used for determining the location of sound in the vertical plane.

Head-Related Transfer function – The size and shape of the head affects the perception of sound as well.