Human Understanding, Randomness, Free Will, and Delusion Part IV

Kent Bottles

Posted 3/16/12 on Kent Bottles Private Views

In many ways this long and meandering four-part blog post is entirely Michael S. Gazzaniga’s and Benjamin Libet’s fault. We have already met Gazzaniga and his left-brain interpreter theory that resulted from studying split-brain patients who underwent surgery to treat epilepsy. Gazzaniga has explored what these studies mean in several books, all of which are written in a way that the layperson can understand. David Wolman has recently published in Nature a nice overview article that would be a good place to start for someone just starting to grapple with their brain’s inherent need to explain things, even when the brain does not have a clue as to what is really going on (

As shocking as my brain’s need to confabulate to make sense of a world that increasingly makes no sense is the work of Benjamin Libet of UCSF who stimulated the brain of an awake patient undergoing surgery; he discovered a time lapse between stimulating the cortex that represents the hand and when the patient signaled they were conscious of sensation in the hand. In more recent studies, John-Dylan Haynes showed that the outcomes of an inclination can be encoded in brain activity up to 10 seconds before the patient is conscious of it. Chung Siong Soon also expanded Libet’s work when he showed that regions in the cortex associated with voluntary movement lit up on fMRI scans five seconds before the subject was aware of making a choice. Song concluded that a network of control areas in the brain “begins to prepare an upcoming decision long before it enters awareness.” This phenomenon has been labeled Bereitschaftspotential, which I cannot pronounce, or readiness potential, which is easier for me to say. Gazzaniga summarizes the staggering implications of these experiments:

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How City Living Affects The Brain

Dov Michaeli

First published 6/22/11 on The Doctor Weighs In

“Everybody knows” that living in the city with overcrowding, high pressure and anxiety-provoking situations is bound to affect you somehow, and not in a good way. But is it a fact? We don’t know. What “everybody knows” is likely to be wrong, and Intuition is no science.

Physicians practicing in inner city settings know from experience that a large proportion of their patients suffer from chronic anxiety and mental illness. But this, too, does not amount to science.

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Survival and Music

By Dov Michaeli

Survival and music? I am sure your reaction is some variation on ‘give me a break!’ Well, read on and you’ll be surprised.

By now every fifth grader has heard about the limbic system in the brain. But in case you already forgot, it is a system of highly interconnected brain structures that integrates stimuli of emotional content and coordinates reactions to those stimuli. For instance, the structure called the amygdala (see picture on the right) receives stimuli that have to do with survival, and it engenders reactions to them, such as fear and aggression (the familiar flight or fight response). The limbic system also contains the nucleus accumbens which has to do with reward. If you are an ape and an attractive female telegraphs her receptivity to sexual intercourse, it makes a certain area in your brain secrete copious amounts of dopamine which in turn arouses the nucleus accumbens, and you.

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