Here is a picture from my 1998 Scientific American review of a split brain patient using his left brain interpreter to explain why the left hand is pointing to the shovel. In brief each brain sees a stimulus, the left talking/interpreting brain sees a chicken claw and the right, silent brain sees a snow scene. Each hand points to the most appropriate answer. The left brain/ right hand points to the chicken to match the claw and the right brain/left hand points to the shovel, to match the snow scene. When asked why the patients was doing that, the left brain answers, "Oh the chicken claw goes with the chicken and you need a shovel to clean out the chicken shed." The left brain, through its interpreter is always trying to explain our actions.