The scroll, the open book, the severed arm, the severed head and the builder's square are all occult symbols used by a number of esoteric groups.
When the Studio was painted, in 1925, Picasso had a close relationship with the Surrealist movement and its leader, André Breton.
Breton sourced many of his ideas for The Surrealist Manifestos from Alchemy and other types of magic.
He encouraged members of the Surrealist group to become "artist magicians" and share an irrational world view in which the paintings they produced would exert a secretive, magical influence upon the world.
Canseleit, a prominent French alchemist of the same period, described Breton as, "a leader of a school of Alchemy, like himself".
By the 1920's, Paris had for decades been at the center of an occult revival. It was into this highly-charged occult atmosphere, at the turn of the century, that Picasso was drawn, through his association with Max Jacob, Alfred Jarry, Guillaume Appolinaire, and later, Erik Satie, Jean Cocteau and Serge Diaghilev. As part of the background to all this, Picasso was fascinated by ancient myths and legends and was also conversant with the symbolisms of the Tarot and Astrology.
By the time of the Surrealists, Picasso was already recognized as a Magus or master-magician. Indeed, he was the spiritual figure head for most of the group, even though he was never a member.
It is perfectly reasonable to assume, that Picasso may have been initiated into an occult group, in or around 1925. This group may even have some connection with the "Prieure de Sion," whose leadership has been linked with both Debussy and Jean Cocteau.