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Weekes: ... On Monday, we talked about the frontal lobe and the variety of functions that it subserves. We also discussed the heterogeneity of these functions and the fact that this is not specific to the frontal lobe. Every part of the brain is involved in a variety of different functions and, if you want to understand the localization of a particular function, you can’t just look at one area of the brain but at a combination of areas that work together. Today we’re going to focus on what happens in the anterior part of the frontal lobe, which we refer as the

Julie: prefrontal cortex.

Weekes: One of the amazing things about the prefrontal cortex is that if you had to localize the part of the brain that seems most responsible for differentiating you from me, you’d talk about the prefrontal cortex. We know, when individuals have damage to the most anterior parts of the brain, it changes their personalities. That’s a sort of difficult thing to study because you have to ask yourself first what we mean when we talk about personality. What are the characteristics that you think of that determine someone’s personality?

Doris: How someone interprets a situation…whether the glass is half empty or half full.

Weekes: Interpretation on a number of levels. There are a variety of other functions that may be indirectly related to personality.

Julie: The ability to organize. ...

Weekes: ... What distinguishes the prefrontal cortex from any other part of the brain, ontogenetically and phylogenetically, is that it is involved with your ability to execute higher level thinking, to organize your environment, to organize goal-oriented behavior. The argument is that it’s those executive functions that at least partly distinguish us from other species. These are not just automatic behaviors. These are not just reflexes. As the frontal lobe starts to develop, you get an inhibition of stimulus-response activity. You lose some of those early reflexes. Why do you lose those early reflexes and what takes their place?

Aakash: Inhibition.

Weekes: Why do you want to inhibit some behaviors?

Aakash: So you can accomplish more complex goals.

Weekes: I talked to you about how we test emotional intelligence. There is a test that’s my favorite because I get to talk about my niece. You put a kid in front of a marshmallow or a chocolate bar and you say, “OK, little child, if you want to have the marshmallow or chocolate bar right now, you can. But if you can wait, if you can inhibit your stimulus-bound desire and wait until I run an errand, you can have two marshmallows when I come back.” I tried this with my niece and the child had the marshmallow in her mouth before I could finish explaining the test. (Laughter.)

Weekes: The idea behind lobotomies was that, when the prefrontal cortex is damaged, individuals change their moods; they change the way they interact with the environment. These findings and a variety of other findings were used by a number of physicians and neurologists to argue—and remember, at this point we don’t have drugs to treat mood or psychotic disorders—that if we modify activity in the frontal cortex, we can change a person’s personality. That what we should do for people in institutions is to think about removing just a small piece of one of these lobes. So Egas Moniz won the Nobel Prize for his work arguing that lobotomies would be the most humane thing we could do for individuals with mood disorders or psychosis. And as bizarre as that may sound to us now, at the time the alternatives were things like—What was being done at the time to treat people with clinical disorders?

Peter: Electric shock.

Noah: Lock them up.

Brooke: Water submersion. ...

Weekes: ... There was a variety of techniques used in lobotomies. One was to take what looks like an awl and put it up through the orbit and go like this ... swwwisshh! What they would do is try to separate the connections between the prefrontal cortex and the limbic system. The argument for doing that was that the changes in mood weren’t just changes in the prefrontal cortex but in the connections.

Weekes: Part of what allows us to make decisions and strategize and have goal-oriented behaviors is not just what the prefrontal cortex allows you to do, but also the connection between the prefrontal cortex and information coming from the limbic system. Not only do I understand this cognitively and strategize intellectually, but I can make this connection to emotionality. And that connection—it sounds very Freudian—is what distinguishes us all at the highest level. That’s why people argue that this level of the brain is important in determining an individual’s personality. When you and I are about to make a bad choice, there’s something from the limbic system, that sympathetic arousal, that causes you to rethink what you’re about to do. So, one argument is that the reason people go from being quite rational and reasonable to making bad decisions is the lack of this connection. ...

Weekes: One of the ways to demonstrate that connection is called the gambler’s paradigm. Let’s say you’re given two sets of cards. With one set you can turn over a card and get a big payoff, but when you turn over the next card, you can get an even bigger loss. You may win $500, but on the next card you could lose $1,000. On the other side, you have cards where you can win a smaller amount, but when you turn over a losing card you lose even less than what you just won. Most people, over time, will figure it out—they’ll go for the small wins because, in the end, they wind up with more money. People with dorsal-lateral prefrontal lobe damage figure it out too. Like you and me, they’ll try for the big win—we all make risky decisions even though we know they’re not such good ones. The difference is, as soon as you or I put our hand over the stack of cards that is riskier, we get a sympathetic response, an excitation. But for people who don’t have the connection between the orbital frontal cortex and limbic system, there is no excitation. What the orbital frontal cortex gives us is a way of regulating how much of our behavior is motivated by lower-level emotional processing and how much is dominated by what we think of as higher-level cognitive processing. There is a lot of evidence to suggest that the prefrontal cortices are involved in a variety of different types of higher-level emotional processing, higher-level decision-making, higher-level strategy formation, all of the things that allow us to move around the world and not just respond automatically to our environment, but instead, to respond through higher-level thinking and decision-making and regulation between the cognitive self and the emotional self. ...