Place Theory

Place theory of hearing: different frequencies excite resonant areas on the basilar membrane (BM).

The cochlea converts a vibration in time into a vibration pattern in space (along the BM);

This, in turn, excites a spatial pattern of neural activity:

• different nerves go to different parts of the BM to pick up the pulses caused by vibrations
• nerves that transmit information from different regions of the BM encode frequency tonotopically (tono = frequency and topos = place);
• neural firing rate is a function of place (highs near the oval window and lows toward the other end);

Experiments on cochleas removed from human cadavers allowed for observation of wavelike motions of the BM in response to sound.

Place theory explains MANY--but not ALL--aspects of auditory perception.