Doppelkopf is a brainfloating technique (see Brainfloating Principle by Harald Bream) that is performed in teams of two.
In the process, each of the partners identifies with one hemisphere of the brain and its focal competence. Although the hemisphere division of the brain, to which Harald Bream referred in 1989, is now obsolete from a neuroscientific point of view, it can still be used today as a creativity technique for focusing the polar abilities of the brain.
Where exactly the cognitive and emotional abilities are located in the brain is of secondary importance for a successful performance of the technique Doppelkopf.