Module 8. 1: the auditory system: language production was one of the first cognitive abilities to be localized in the brain. Frequency rate of vibration / the number of wave cycles completed per unit of time: measured in hertz (hz) cycles / second, human ear can perceive vibrations between 20-20,000 hz. maximally sensitive to sounds between 1000 and 4000 hz (human voice: codes for pitch. low frequency = low pitch: range of frequency that an animal perceives varies widely across species. Timbre complexity of sound: fourier analysis a mathematical process in which complicated sounds are broken down into simple component waves. used to compress complex sounds on computers (mpeg-1, mp3) so that the series of simple wave forms can be efficiently represented. The ear: transduction the ear detects and amplifies very subtle vibrations and transforms these vibrations into neural signals. collectively, the bones are referred to as ossicles.