Michael Gazzaniga provides compelling evidence that his findings apply to everybody. In his book The Mind's Past he describes scientific experiments demonstrating that our highly-vaunted free will is part of a system that rationalizes our actions after they have been done.
Here is a summing up of the book. The mind's past is the brain's past in that natural selection evolved the brain and we are its creatures. Survival of our species resulted from the four F's. Feeding, fleeing, fighting, and f*king. The minds's past is also the brain's past in that what comes to mind has already occurred in the unconscious. Our conscious mind can be compared to a primitive computer with a few kilobytes of RAM. 95 percent of brain activity happens below the surface. (As examples, the brain uses the kidney system to clear toxins and to regulate our metabolism). Finally, because the conscious mind finds out after the fact our brain tells stories explaining why we do things, even though the stories can be total fabrications. Our lives can be described as muddling on through with our brains trying to interpret events to survive.
He came to these conclusions after working with split-brain patients and studying their reactions to certain situations. From his studies he arrived at the what he calls the interpreter, an unconscious process in the brain. He locates the interpreter in the left (language) hemisphere. To it falls the job of making sense of our behavior.
The implications of his research are enormous, with huge consequences for society should they become widely and publicly accepted. In short, one pattern of belief would be replaced by another. Society would come to accept that we are creatures of narrative fiction and that we explain our actions after they are done. Attendant upon that acceptance would be that we have no free will. We pause when we think about the consequences for the penal/justice system, which assumes freedom to choose between good or ill. The entire legal system would be revamped, if it could be.
Gazzaniga's thesis is that we are puppets controlled by our brains. Our brains are clever indeed, even producing the illusion that a self is in control of its thoughts and actions. This is typical of neuro-research, and such research findings/opinions so disturbed Tom Wolfe that he wrote his well-known "Sorry, But Your Soul Just Died."
Near the opening Gazzaniga has this to say: "We think our personal selves are directing the show most of the time. I argue that recent research shows this is not true but simply appears to be true because of a special device in our left brain called the interpreter. This one device creates the illusion that we are in charge of our actions, and it does so by interpreting our past--the prior actions of our nervous system."
Large circuits from the eyes form an X-pattern to the occipital cortex at the back of the brain. That is, circuitry from the left eye goes to the right side of the brain and vice versa. An example of illusory control can be found in some epileptics who have had the corpus callosum severed to eliminate their seizures. It connects the right and left brain hemispheres and without it the two sides do not "talk" to one another. A split-brain patient is shown an image in his left visual field (the left half of what both eyes take in) and cannot name what he has seen. Why? Because speech-control is on the brain's left side and left-field images are sent only to the opposite, right, side of the brain. which has no language function.
Take a split-brain patient and flash a picture to only one side of his visual field. Suppose a picture of a chicken is flashed from the left visual field to the right brain only. The patient cannot say what he is seeing because the left hemisphere, the interpreter, controls language, and the right side is severed from it. Still, if asked to point to the chicken picture the patient can do it because the interpreter is not involved. He or she does not have to use language at the moment unavailable from the left side.
The interpreter plays tricks to maintain the illusion of control. When a patient's right brain is shown a command like WALK, he begins to walk to the door. When asked why he is leaving, his interpreter has an answer for the researcher: To get a drink of water.
Gazzaniga had a patient, W.J., a World War II paratrooper hit on the head with a rifle butt, which eventually caused seizures. Gazzaniga did before-and-after trials. Before the operation to sever the corpus callosum, splitting the two brain hemispheres and anterior commissure, he presented W.J. with stimuli to the left and right visual fields. The ex-paratrooper performed the tasks perfectly. After surgery W.J. was presented with letters and light bursts flashed to each visual field.
What happened? W.J. verbally reported stimuli when it flashed to his right visual field as it "lit up" neurons in his left (language or interpreter) hemisphere. Not so when his left visual field (right hemisphere) was stimulated. He could not verbally report it while he could perform motor action by pressing a button. They tried again with the left visual field, this time asking him to point to the stimulus rather than verbally identify it. With the motor functions of his brain he could do so.
Then there was P.S., a teenage boy. He had a crush on a girl but could not say her name when the word "girlfriend" was flashed to his left visual field (right hemisphere). Though he could not say it, with his left hand (right hemisphere) he spelled "Liz" with Scrabble tiles. Somehow the right hemisphere completed the task through motor movements with the left hand.
Gazzaniga writes of the fictional self, as evidenced by the interpreter in the left hemisphere. He explains it as a narrator that reconstructs our past and weaves it into a life story. As narrator, it promotes the belief (for Gazzaniga, read "illusion") that we are in control of our story. It is the "spin doctor" making sure we receive convenient explanations. Yet, most of our neurons fire below the level of consciousness and thus outside our awareness. I do not have to make a deliberate decision on each of these keys as I type.
Gazzaniga urges that today too much importance has been assigned to environment and neuroplasticity. In his work with obsessive-compulsive patients and neuroplasticity Jeffrey Schwartz would be among those who differed with him. (See Schwartz, Neuroplasticity and The Power of Mental Force.) Divided on simplistic lines, we have here the nature/nurture debate, in which Gazzaniga comes down on the side of nature. He sees in brain modularity and genetically-driven mechanisms a powerful argument for nature, which will do what it must do without shaping by nurture.
In short, our brain and its mechanisms control cognition as well as behavior and leave the false impression that they have been controlled, and are not the controllers they are. Note the above illustration from the book. A brain drags somebody into the future, while he lags behind in an illusory "now." Gazzaniga boldly opens the third chapter with this declaration: "By the time we think we know something--it is part of our conscious experience--the brain has already done its work. It is old news to the brain, but fresh to us." This puts an end to the self and its belief in control, he in effect says.
Elsewhere in the book he explains that most memories serve the narrative self in that events are reconstructed to support belief in the continuity of self and personality. Popular lore has memory as a trove of organized recollections and when one part of the brain is stimulated by a modern Wilder Penfield a certain memory sparks up, and with a different part a different memory. Not so, according to the author. Instead they just help the brain's interpreter.
Gazzaniga's findings on our belief in choice appear to have support in the experiments of others. In his now famous experiments Benjamin Libet found compelling evidence that we have no free will. He found that the brain had already decided roughly a half-second before the subject became consciously aware of the decision. In the experiments of John-Dylan Haynes people were placed in a brain scanner where a screen flashed random letters. They pressed a button whenever they felt the urge and recalled the letter relevant to their decision to press it. Haynes and his group found brain activity predicted by several seconds the decision to push the button, long before people were aware of making a choice.
In ancient teachings handed down for millennia both Advaita Hinduism and Buddhism have said that in deepest experience one comes to realize there is no self as well as no doer and, that being the case, free will and one's life story are also a fabrication. Modern practitioners after years of meditation or by happy accident corroborate the teachings through realization in their own lives. The realization, if full by recognizing tat tvam asi (that art thou: boundaries are illusory), is attended by liberation into Awakening, or Enlightenment as termed in modern times.
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