PSYC 100 Lecture Notes - Lecture 10: Basilar Membrane, Eardrum, Sound Intensity

• School: Queen's University
• Department: Psychology
• Course: PSYC 100
• Professor: Jill L Atkinson

Document Summary

Sound results from vibration, causing the air molecules to compress and rarefied: compressed molecules are in regions of high air pressure, rarefied molecules are regions of low air pressure. Compression occurs at the peaks and rarefactions at the trough of the waveform. Sound waves also have a wavelength and amplitude: amplitude determines intensity. Intensity cue: difference in timbre based on location: wavelength is closely related to frequency. Frequency: the number of cycles between high and low pressure in one second (hz: if one compression and one rarefaction occur within one second, the frequency is 1 hz. The human range of hearing is ~20 to 20,000 hz: by mid-adulthood the highest audible frequency drops to 10,000 15,000 hz. We are most sensitive to sound between 1,000 and 4,000 hz. A waveform"s intensity is related to loudness: intensity is measured in decibels (db)