Psychology 2015A/B Lecture 6: Lecture 5 pt 1

• School: Western University
• Department: Psychology
• Course: Psychology 2015A/B
• Professor: John Campbell

Document Summary

T(cid:449)o defi(cid:374)itio(cid:374)s of (cid:862)sou(cid:374)d(cid:863: physical definition: pressure changes in the air that cause sound waves, perceptual definition: the experience we have when we hear. Sound as pressure changes: a sound stimulus occurs when the movements or vibrations of an object cause pressure changes in air, water, or any other elastic medium that surrounds the object. The decreased density of air molecules caused by rarefaction causes a slight decrease in air pressure: the cycle of this process creates alternating high- and low- pressure regions that travel through the air, note: physical definition of sound. Frequency: number of cycles per second that the pressure changes repeat: measured in hertz (hz): 1 hz is one cycle per second, perceived as pitch, tone height is the increase in pitch that happens when frequency is increased. Figure 2: perception of: high vs. low frequency. Three different frequencies of a pure tone: higher frequencies are associated with the higher pitches, pitch.