Conversation so far:
what is known about barrett in this section?
The second album, Barrett, was recorded more sporadically than the first, with sessions taking place between February and July 1970.
how was barrett received?
Shirley said of Barrett's playing: "He would never play the same tune twice.
what is the highlight of this section?
" At times Barrett, who experienced synaesthesia, would say: "Perhaps we could make the middle darker.
and what followed this?
These sessions were happening while Pink Floyd had just begun to work on Atom Heart Mother.

Question: what did they do while working on atom heart mother?
Self-contained rewrite: what did  Pink Floyd do while working on atom heart mother?