A lot of work in HCI was done from the 1960s onwards. The mid 60s saw the development of manipulating graphics on screen with a pointer, and then the beginnings of the other aspects of WIMP (windows, icons, menus, pointers). The mouse was developed by Stamford Research Laboratory in 1965, to replace the light-pens which had been the only option before then (Though it wasn't used commercially until the end of the 1970s). Windows came into use in the mid 1970s, first tiled, then overlapping, and it was Apple that led the way in implementing them. WYSIWYG was introduced in the mid 1970s and was a major step forward.
HCI was developed for the generation of music at a similar time. In 1972, Salvatore Martirano built The SalMar Construction. This was a 400lb monster with 291 controls, 24 speakers and the ability to allow the user to control every aspect of a large amount of pre-programmed material. The machine has touch-sensitive switches and could change between acting on micro and macro processes during performance.
A more recent interaction between humans and computers is George Lewis' Voyager, which plays music depending on the real-time input of a human player. It effectively improvises as would someone playing with you in a band, both developing your ideas and adding its own. Lewis designed this because there was no other computer system capable of this improvisational technique. Performance using Voyager allows the user to input new material at any time, with the computer using any input to guide its output, without depending on it in a strictly logical way.