SPLIT BRAIN PATIENTS
To continue with the split brain patient information (basic info here), this is an interesting, albeit old, documentary with Gazzaniga and his data. At about 8:43, you can see the block task I had mentioned before. Basically, in this task, a subject is given a few blocks that are half dark and half light. By arranging these blocks in a specific pattern, you can match images and test spatial reasoning. You can see that with the left hand (right hemisphere), the subject is able to arrange the blocks to match the picture very well. However, with the right hand (left hemisphere), the subject cannot get the blocks arranged correctly. The left hand even tries to jump in and help- at this point, with the two hemispheres severed, the hands are working as separate entities governed by separate brains. The right hemisphere can do the task easily and therefore wants to do it- the left hemisphere, which is supposed to be doing the task, cannot do it accurately. Imagine how frustrating it would be to see someone doing a simple task incorrectly- that is how the right hemisphere feels- and without the corpus callosum to connect it to the left, the left hemisphere is incapable at this task and can’t get the basic assistance it needs.