Notes on The Decisive Moment : How the Brain Makes Up Its Mind

Posted by Andy Gavin on Thu, 2009-03-05 16:41

BBC Radio 4's Book of the Week is interesting: Decisive Moment, The: How the Brain Makes Up Its Mind is how people make decisions. The programme which is available seven days after it is broadcast on the site has readings all week from the book. The book shares some ground with Blink! which I'd blogged about a couple of years ago, except this has a broader theme about how emotional response plays a part in decision making. Covered over the week are some interesting insights into the mind and how it works including how to learn. The program brings together some of the research into the human mind from the last decade, in an anecdotal form, of dopamine in decision making. The five programmes had a different theme, which I've attempted to find further references on:

How do people make decisions

She who wants right without wrong;
order without disorder;
does not understand the principles
of heaven and earth.
She does not know how
things hang together
---Chuang Tzu, 4th century BC

There is a thin line between a good decision and a bad decision in some cases. For centuries there have been untestable theories of what was happening inside the head when decisions are made. From Plato's time there has been a view that reason battled with emotion to make rational decision. It has only been recently when theories could be tested that it has become clear that emotions are needed to make decisions. Without emotion/desires everyday decisions become impossible. When highly experienced people have to make decisions these decisions can become emotional responses, the learned response is a feeling. Retold was a story from Descartes’ Error: Emotion, Reason and the Human Brain of the study of Eliot who'd suffered brain damage. He had been an affectionate husband and father. He'd since become unable to feel emotion remaining detached.

He retained lots of cognitive functions: he could perform calculations, had a fine memory for dates and names, and the ability to discuss abstract topics and world affairs.” After surgery, “he was even less able to care about things or to rank priorities. He could stick obsessively to a task and perform it well; but on a whim he might shift attention and do something completely different. Intelligence testing showed him to be a superior intellect. His emotions were askew, though. He could no longer set priorities or make decisions. He had no sense of the relative importance of any situation.

The study showed, alongside others that it is necessary to have the emotional systems in the mind working to set priorities and make decisions. Erich Vieth blogged about this here. One thing that is interesting is these studies are becoming useful in other fields such as ecomonics.

Why should this be so, evolution might hold an answer. The human brain is a unique and a before humans evolved there were already many creatures with advanced brains on earth. Brains take a long time to evolve and the unique human brain new, and imperfect. As a result the human brain often uses the facilities of the highly evolved brain in all activity.

The real value of making mistakes

We are generally better persuaded by the reasons we discover ourselves than by those given by others ---- Blaise Pascal

Sometimes strong feelings can point the way then there seemingly is not a choice. Scientists have found that dopamine regulates our emotions. By watching the dopamine system we can find out a lot about decisions. Research based on that by Schultz shows that the dopamine system is key to not repeating the same mistakes again. Mistakes aren't something to be discouraged making mistakes is the best way to learn deeply. Years of mistakes can be translated into emotional responses. Seed Magazine's A New State of Mind is an article about some of this research.

Flaws in decision making can lead us to take excessive risk
Defects in the emotional brain can cause people to take on excessive risk. Limiting dopamine in the brain is shown to cause people to take excessive risk. Suffers of Parkinson's disease are often prescribed dopamine agonist: that mimics the role of dopamine in the brain. Some Parkinson's patients prone to gambling and excessive risk when they are on the agonist. Studies suggest 13% of those on agonist have gambling addictions. Dopamine system gets excited by predictable rewards, but even more so by unexpected reward: causing a rush of dopamine. Random rewards creates the brain to see patterns that aren't there. There are some evidence that the flaws in the dopamine system cause investors to see patterns in random data like the markets.

When a person is confronted with an uncertain situation people do not carefully evaluate the decision: they hardly do any thinking at all. This is referred to as Prospect Theory. The New York times had a story on it. Also the Boston Globe tells a similar story to the one found in The Decisive Moment

Even when the brain is functioning correctly, it is difficult for the brain to resist choosing a short term gain over a more lucrative long term gain. Dr Johnathon Cohen showed using an MRI machine that a choice between a short term gain and a long term involved an emotional decision.

The role of the pre-frontal cortex in making creative decisions
Sometimes the pre-frontal cortex can override an instinctive decisions with creative thinking. In times of crisis when the best way out is counter-intuitive the people are able to dismiss what feels right to make a creative decision. Something that is uniquely human and creates new ways of solving problems. The pre-frontal brain is uniquely human: something that human ancestors don't share.
One source of scientist's knowledge on the pre-frontal cortex is from damage and disease. From the days of frontal lobotomies, through to tumors on the pre-frontal lobe preventing choices from being made correctly. One study was by Dr. Kenneth Heilman on a young girl: Mary Jackson had a bright future, though she had grown up in a poor inner-city neighborhood she won a scholarship to an Ivy league university. In her first two years she made the dean's list every semester. However something went wrong in her sophomore year. Although she had been raised a devout Baptist who rarely drank alcohol she began to drink alarming amounts, started sleeping around, broke up with her long term girlfriend and ultimately ended up on crack. Her grades slipped and she became angry and verbally abusive: her performance and health continued to deteriorate throughout the year. She finally saw a doctor for a case of pneumonia that would not go away. The doctor revealed a dread diagnosis: Mary Jackson had become infected with HIV and now was suffering from AIDS. Mary said she could not understand her behavior, the doctor suspected a personality disorder, but she had one other symptom that made him suspicious: she had not had a menstrual period for months. Suspecting a disorder of her pituitary gland, he referred her to the neurologist Dr. Kenneth Heilman.

Dr. Heilman found that Mary had lost her drive to achieve long-term goals, could not avoid seductive situations, and had become short-tempered and easily frustrated. She also showed signs of environmental dependency syndrome: Mary was highly influenced by her surroundings. Showed a table on which there was a comb, and told not to touch the comb, she would immediately take the comb and start combing her hair.

Using the MRI Heilman found that Mary had a tumor on her frontal lobe that once removed Mary returned to her old self. This illustrates the role of the frontal-lobe in choice.

Another more shocking case was presented at the American Neurological Association by Russell Swerdlow and Jeffrey Burns: a teacher whose brain tumor turned him into a pedophile.

These cases indicate that the human part of the brain plays a part in regulating decision making, without it people are much more susceptible to their environment.

The certainty trap
Sometimes we think we have made up our minds when we have not. Clear-cut decisions are not always based on absolute certainty: when you think you have made up your mind on the facts you've often dismissed information. One study mentioned was by Philip Tetlock who assessed 82,361 predictions by 284 political pundits to check their accuracy. In his conclusion noted there were two cognitive styles: the hedgehog or the fox:

The hedgehog
is said to know one thing and know it well. He sees events and trends in terms of his big idea, and aggressively extends it into new realms. Hedgehogs tend to be confident in the applicability of their fundamental concepts and impatient with those who "do not get it".
The Fox
in contrast know many small things which they bring to bear in their analysis in a dynamical and flexible way. They tend to be uncertain and flexible, "on the other hand" types who are skeptical about their own predictive ability and in fact about the whole enterprise of making predictions in such an intractable realm.

He found, because the media liked to select experts--- who have strong opinions rather than balanced--- that the most famous pundits had the most unreliable predictions: they were hedgehogs.

A number of studies (Link, link) have also been conducted using MRi machines to see what areas of the brain were used when making political decisions, despite being given facts that should be evaluated in making a decision subjects mainly chose using emotion: they were not evaluating the information that might change their preconceptions. A Confirmation Bias.

Having all the facts is often not enough, preconceptions and biases cause some facts to be overlooked. When making decisions we should actively resist the urge to suppress argument. Also when explaining a something, often the facts will not speak for themselves.


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