People with it, also known as amusics, truly can't hear the difference between two pitches.

患有这种疾病的人，真的听不出两个音高的区别。

Like, amusic people can still tell people apart by their voices and pick out different noises in their environment.

就像，失歌症患者仍然可以通过声音来区分不同的人，并在他们的环境中挑出不同的声音。

For instance, a 2007 study looked at 71 members of 9 families that had at least one amusic person in them.

例如，2007 年的一项研究调查了 9 个家庭中的 71 名成员，其中至少有一名失歌症患者。