I occasionally like to go far afield from judgment and decision making, and here I go again. This post takes a look at Michio Kaku’s 2014 book, The Future of the Mind–The Scientific Quest To Understand, Enhance, And Empower The Mind, Doubleday, New York.
Decision models can sometimes seem very explanatory, but they seem so simple minded when I read in Kaku’s book that we have two separate centers of consciousness and that we may all have photographic memories.
Two separate centers of consciousness
Kaku looks at the experience of Dr. Michael Gazzaniga, who has spent several decades studying split-brain patients. At first, these split brain patients seem perfectly normal. They can carry on a natural conversation but there is something very different about them. Normally the hemispheres complement one another as thoughts move back and forth between the two. The left brain is more analytical and logical. It is where verbal skill are found, while the right brain is more holistic and artistic. But the left brain is the dominant one and and according to Gazzaniga makes the final decisions. Commands pass between the left brain and the right brain via the corpus callosum. But if that connection is cut, it means that the right brain is now free from the dictatorship of the left brain. The right brain can have a will of its own and contradict the wishes of the dominant left brain.
This creates the bizarre situation where the left hand (controlled by the right brain) starts to behave independently of your wishes, as if it were an alien appendage. A woman reported that she would pick out a dress with one hand, only to see her other hand grab an entirely different outfit. Meanwhile, one man had difficulty sleeping at night thinking that his other hand might strangle him.
For the rest of us with an intact corpus callosum, Dr Gazzaniga’s experiments show the left brain will make up an answer to explain inconvenient facts. The experiments need to be clever because the right brain cannot talk. Dr. Gazzaniga believes that this propensity to make up answers gives us the false sense that we are unified and whole. He calls the left brain the “interpreter”, which is constantly lining up ideas to paper over inconsistencies and gaps in our consciousness. For example, in one experiment, he flashed with special split frame glasses the word “red” to just the left brain of a patient, and the word “banana” to just the right brain. (Notice that the dominant left brain therefore does not know about the banana.) When the subject was asked to pick up a pen with his left hand (which is governed by the right brain) and draw a picture. Naturally he drew a picture of a banana. Remember that the right brain could do this, because it had seen the banana, but the left brain had no clue that the banana had been flashed to the right brain. Then he was asked why he had drawn the banana. Because only the left brain controls speech, and because the left brain did not know anything about a banana, the patient should have said,”I don’t know”. Instead he said, “lt is easiest to draw with this hand because this hand can pull down easier.” Dr. Gazzaniga noted that the left brain was trying to find some excuse for this inconvenient fact, even though the patient was clueless about why his right hand drew the banana.
Dr. Gazzaniga concludes, “It is the left hemisphere that engages in the human tendency to find order in chaos, that tries to fit everything into a story and put it into a context. It seems that it is driven to hypothesize about the structure of the world even in the face of evidence that no pattern exists. This is where our sense of a unified self comes from. Although consciousness is a patchwork of competing and often contradictory tendencies, the left brain ignores inconsistencies and papers over obvious gaps in order to give us a smooth sense of a single “I.” In other words, the left brain is constantly making excuses, some of them harebrained and preposterous, to make sense of the world. It is constantly asking “Why?” and dreaming up excuses even if the question has no answer.
This reminds me of Justifying our Decisions: Great for Plausible Deniability, not so Great for Medical Diagnosis. The left brain seems to have the role of elephant driver, but in Gazzaniga’s scenario it is actually dominant–a very well trained elephant.
Over time there have been examples of people with special memory abilities or calculation abilities after sustaining damage to the left brain. The savant skill of photographic memory may be initiated by some sort of injury to the left brain leading to right brain compensation. This still does not explain how the right brain can perform these miraculous feats of memory. In 2012 a new study showed that the key to photographic memory may not be the ability of remarkable brain to learn, on the contrary, it may be their inability to forget.
In a study done by scientists at the Scripps Research Institute in Florida working with fruit flies, the fruit flies were exposed to different smells and were given positive reinforcement (with food) or negative reinforcement (with electric shocks). The scientists knew that the neurotransmitter dopamine was important to forming memories. To their surprise they found that dopamine actively regulates both the formation and the forgetting of new memories. Previously it was thought that forgetting might be simply the degradation of memories with time, which happens passively by itself over time. This new study shows that forgetting is an active process requiring intervention by dopamine.
The two separate conscious selves makes me think of parallel constraint satisfaction theory and bidirectional reasoning. Maybe the left brain is in charge of bidirectional reasoning. Kaku and his sources seem to believe that the left brain wins all the battles if your corpus callosum is intact, but maybe it just wins almost all the battles. I am also reminded of Kluge-the Haphazard Construction of the Human Mind. Kluge asserts that the brain is a bunch of modules stuck together. It seems to me that the brain may have been more like a computer with memory and rationality, but that evolution has determined that social skills are more important than purely cognitive skills and has thus devoted extreme amounts of brain power to that end. However, clearly there may be times when the human race would benefit from greater cognitive powers. Is there a more or less one to one trade off between social skills and cognitive skills in our brains? Could we somehow push the brain to devote more power to one or the other. It seems that we have done that to some extent with reading and numbers?