September 19, 2007

• I feel like that a lot.
• Nice video. But Gazzaniga surely goes much too far in the conclusions he draws. Facts about the interaction of the two hemispheres in a commisurotomy patient don't prove anything about the normal interaction of conscious and unconscious processes. It may well be that unconscious processes are hugely influential in the way he suggests, but these experiments don't show that.
• Fascinating. I'm just disturbed by the advert for 'Mind Hacks'... Frederick Pohl's Jem describes UN translators who have this procedure done so they can do their job better. Causes migraines.
• I'm in two minds about the procedure.
• Hemisphere ... hemisphere ... you know, I do feel funny ...
• I got the creepy impression that the non-verbal, disconnected half of the brain had its own separate consciousness, as though this individual were now somehow the vessel for two separate conscious entities, one verbal, one not. This is scary because it suggests an orphan half-brain without the ability to communicate either with its former "other half" or with the outside world other than by drawing. I wonder what kind of artwork that half might produce if permitted to do so unprompted, or if bisection removed the motivation needed to undertake same. Pondering this makes both sides of my brain hurt.
• An interesting idea when you think of the 19th century spiritualists using similar techniques as a divinatory process. Yeats' wife (I think it was his wife) wrote out an incredibly complex (and often incomprehensible) world view through automatic writing, perhaps she was "seeing the saw" in a similar way?
• I don't think it's really like that, though, kinnakeet. There isn't one 'disconnected' hemisphere and one in control (although one is in charge of talking). Each hemisphere controls one side of the body, just as normal, but in spite of the cut they work in perfect harmony. The person who has undergone the operation can walk just as well as ever - you don't get problems from one side wanting to veer off or not knowing where the person is going. If the 'split-brain' person was typing a letter he could switch from using left to right hand - and hence switch control from one hemisphere to another - and back again without the slightest danger of confusion about what to type (I think so, anyway). It's only in very strange experimental circumstances that anything at all unusual is noticeable. If you go to great lengths to ensure that only one hemisphere has the data, only one hemispere can express it, but the two hemispheres still belong to one person, one conscious entity. In my view, anyway. Plegmund's left hemisphere speaking, by the way.
• I usually speak through my "southern hemisphere".
• When I was nine years old I shattered the elbow of my dominant arm and taught myself to write using the other hand. Soon afterward I developed a dramatic stammer, becoming unable to speak without involuntary hesitations and stuttering. When my Mom checked with the MD, she was told I had "mixed brain dominance" and that I should cease using my left hand for writing. I did, and the stammer went away. Not sure how that relates but it seems to. The very idea of nerve pathways in the brain being severed just plain freaks me out, I guess. *moves one seat farther away from quidnunc*
• I usually speak through my "southern hemisphere". Well then, Uranus belongs on that other thread.
• The "Interpreter" in Your Head Spins Stories to Make Sense of the World: Our left hemisphere tweaks 
the facts and allows us to feel like we’re 
in charge, experiments with 
split-brain patients reveal.

• See? The Left (Brain) can't be trusted!
• Parallel processors cut off from the other full mugwump set of parallel processors? Let's have a group hug then.