The next-to-last of 12 episodes in this special brain series aired September 30, 2010, and concerned The Deciding Brain. Charlie and Eric Kandel welcomed:
William Newsome studies decision-making on the cellular level by exploring the neural processes that mediate visual perception. He is a professor in the Department of Neurobiology at Stanford University and a Howard Hughes medical investigator.
Tony Movshon studies the brain’s system that controls the simplest form of decision-making — perception. He is a professor of neuroscience and psychology at New York University.
Ray Dolan studies how emotion and cognition interact to produce a decision. He is a professor at University College in London and the director of the Wellcome Trust Center of Neuro-imaging.
Joshua Greene he studies the brain mechanisms responsible for decision-making. He is an assistant professor of psychology at Harvard University and director of the Moral Cognition Lab.
The following excerpts include both moral and neurological considerations about decision-making. (16:23) Following the video clip, I’ve included the transcript of co-host Eric Kandel’s opening comments that establish the context for the discussion. Watch the entire episode online.
Decision-making brings us into a new area of neuroscience. In the past we have considered how different parts of the brain control different aspects of our behavior. Today we’re going to examine how neuroscience impacts on other areas of knowledge. Neuroscience is a font of knowledge for other areas of scholarship.
This is very important, and it’s important since it was first raised maybe 60 years ago by a famous physicist by the name of C.P. Snowe, who wrote a famous essay called “Two Cultures” in which he pointed out that a major schism is emerging between the humanities concerned with the nature of human existence and the sciences concerned with the nature of the natural world. This schism, this separation was based upon the fact that these disciplines distrust one another and fail to understand one another very well.
And to some degree the failure to understand is unidirectional, because scientists have no difficulty enjoying Shakespeare or Picasso, while humanists have a great deal of difficulty understanding quantum mechanics or even brain science. And C.P. Snowe suggested that it’s important to bridge between these two cultures. And there are a number of bridges that have been built. One is what you do, trying to educate the public about various aspects of science. But as we have seen in the last 10 programs, one of the things that’s emerging is that brain science is in fact giving us insights into the nature of human existence. And therefore, it’s in a position to initiate dialogue with various aspects of the humanities, with economics, with philosophy, with moral decision-making, with art, and with literature.
And decision-making in economics and moral philosophy is one area in which neuroscience has made the most substantial progress. It’s fair to say that this is probably the most rigorous of the bridging areas that’s evolving so far. So we want to use this as an example for studying how neuroscience can impact other disciplines. Decision-making has many aspects. It goes from very simple perceptual decisions to personal decisions, to social decisions, economic decisions, and moral decisions.
Let me give you an example. It’s very simple to speak about a personal decision. I can decide I’m going to have dinner tonight at 7:30. I can also elaborate this into a social decision. I’ll have dinner by myself, or will I have dinner with my colleagues around this roundtable. This turns into an economic decision. Will I invite people to a very elegant restaurant which may be expensive, or will I invite them to a pizzeria around the corner? And finally it brings out a moral decision. Am I, as the co-host of this program, going to pick up the tab, or am I going to ask the leader of this group to pick up the tab? As we know, in the past you have always picked up the tab, and I hope you will again tonight. (LAUGHTER)
So anyway, there are a range of phenomena. And we have a very good science for approaching it. And the science dates back to the development of several methodologies about 50 years ago.
Two different approaches began to develop the science of decision-making. One was trying to pick up signals out of noise. Bell telephone company, for example, people working in the Bell Labs were trying to develop methods whereby in a noisy telephone line you could amplify the signal so you could tell the difference between “pole” and “bowl,” two very similar-sounding words, and to sort of pick the signal out of the noise was a task they set themselves.
Another group of people was focusing on picking the signal out of noise — mathematicians trying to develop statistical methods to determine whether a particular scientific finding is reliable or just a signal in the noise.
It turned out that the approaches of both these groups turned out to be very similar and provided an opportunity to really begin to approach these problems in a very systematic way and to study this in a biological sense. And the biological that has emerged is quite fascinating, because even though we’re dealing with a variety of different processes — perceptual, personal, social, economic, moral — it turns out that there are a number of key brain areas involved in all of these.
Now, the fact that brain areas are involved in perception, in personal decisions, is easy to understand. But to think that moral decisions involve the brain is a bit of a stretch. And we want to begin by asking, what is the evidence that moral functions are represented in the brain?
And that dates to a very famous case, a man called Phineas Gage who in about 1848 was working on a railroad and working with explosives, and in the course of working this with steel poles, a steel pole went through his skull from the base here coming out at the top of the skull, damaged his brain very seriously. This physician, John Harlow, a relatively inexperienced physician, took excellent care of him, paying a lot of attention to him, making sure that he really recovered from this, and he recovered to the most amazing degree.
Within days, he was able to walk and talk and function effectively. Within a few weeks he was back in the job. But the amazing thing is that despite the fact he was doing all of these routine things well, he had changed in the most dramatic way. People said “Gage is no longer Gage.” Before this accident, he was the foreman of the crew. He was absolutely reliable. He was like you. You could always count on him to do the job and to do it well. After the accident, he was completely irresponsible. He never showed up on time. He became obscene. He paid no attention to his fellow people. He had really lost a sense of moral judgment. And this was absolutely remarkable.
Now, at the time he died, they didn’t do an autopsy on him. And Harlow presented two major papers which are illustrated in this book. But Hannah and Tony Damasio came back many, many years later, and using the skull and the steel pole that went over him, they reconstructed the pathway of this lesion and realized that one important structure that was damaged by it was the prefrontal cortex, and particularly the under surface, what is called the ventromedial prefrontal cortex and the orbitofrontal cortex.
And we now know from a number of people work, and we’ll discuss this today, that these areas are extremely important for moral behavior for decision-making. And the Damasios and others, and Ray Dolan had a contribution here as well, realized that these prefrontal cortical areas also exert a control over the amygdala, a structure we discussed before, deep in the brain which orchestrates emotion. And that has made a lot of people including the Damasios realize that moral decisions — decision-making and emotions are often tied together, that you cannot separate one and the other. And we’ll hear later on how certain kinds of moral decisions inevitably recruit emotions in a very powerful way.
So we’re going to have a wonderful time listening to the various aspects of emotion that we now begin to understand.