Speech and music perception, two universal human activities, obey principles of perceptual organization just as other aspects of perception do. While speech and music engage the same neural machinery as other, naturally occurring sounds, both have unique acoustic qualities that may require specialized processing that emphasizes either the distribution of acoustic energy over time or the exact points in time at which acoustic events occur. It remains to be learned how these competing demands are worked out in the brain, although some evidence suggests that the two processing strategies may be divided between the hemispheres. Speech and music are also behaviorally potent in that they can evoke strong emotional reactions.

Having completed our survey of hearing, speech and music, we are now ready to consider a trio of senses, touch, taste, and smell, that play subtle but important roles in our everyday lives.