Psychoacoustics—that is the branch of psychology concerned with the perception of sound and its physiological effects.

心学——这是心学的一个分支， 研究音的感知及其生效应。

The psychoacoustic algorithm finds elements in the audio that have exceptionally low volume sounds, very high-pitched sounds, or sounds very close together which the mp3 compression discards, thereby saving space and making it a lossy compression format.

心学算法会在音频中查找音量极低、音调极音非常接近的元素，而 mp3 压缩会丢弃这些元素，从而节省空间并使其成为有损压缩格式。