Psychology 3203

Questions about Hearing to Ponder before Test 4

Summer 2010

1. Understand sound waves and the physical measures of frequency (Hertz) and amplitude (decibel). What does it mean to go from 100 Hz to 200 Hz? What does 0 dB SPL mean? What does it mean to go from 0 dB to 40 dB SPL?

2. Understand describing sound waves as sine waves. In what sense is this description accurate and inaccurate? What happens when sound waves combine?

3. Know the difference between pitch and frequency, loudness and amplitude.

4. Know the structure of the ear. Be able to follow the sequence from a sound wave hitting the pinna to the bending of a hair cell. Understand the different functions of the Inner Hair Cells and the Outer Hair Cells.

5. Consider the cases of a 50 Hz and a 5000 Hz sound signal. Know how these signals affect the basilar membrane and produce hearing according to a frequency/volley explanation and the place explanations of Helmholtz and Von Bekesy.

6. What is a click-induced otoacoustic emission? How does this happen? How can we use this emission to diagnose hearing loss? What is a spontaneous otoacoustic emission? What do these spontaneous otoacoustic emissions tell us about the basilar membrane?

7. What is an audibility function? How is it produced? Know the general shape of the function. What does this tell us about hearing?

8. What is an equal loudness contour? How are they produced? Know the general shape of these functions. Functionally, what does these contours tell us about hearing?

9. What is the amplitude-frequency shift (a.k.a. equal pitch contours)? Know the general shapes of these contours. How are they produced? Functionally, what do these contours tell us about hearing?

10. If I know the frequency of the sound, can I predict the pitch of the sound? If I know the amplitude of the sound, can I predict the loudness of the sound?

11. What were Steven's scales of loudness and pitch? How were they created?

12. Understand the azimuth system for indicating direction.

13. Know how interaural intensity differences contribute to localization of sounds. Does this work with all frequencies?

14. Know how interaural time differences contribute to localization of sounds. Does this work with all frequencies?

15. The duplex theory of sound localization was tested in an experiment by Stevens and Newman. What were the results? What do the results suggest for human hearing?

16. What is the cone of confusion? Why do we have difficulty discriminating between a sound located at 0 and at 180 degrees? Explain why moving your head makes localizing a sound easier.

17. What happens on your basilar membrane when I play a musical chord on a piano? What is a Fourier analysis? How does Fourier analysis contribute to the identification of sound objects?

18. What is the general problem for the hearing system according to Bregman's Auditory Scene Analysis approach?

19. How does ventriloquism work? Can a person really "throw his voice"?