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  • Professor Paul Bloom: So what we're doing today is

  • continuing on the theme of emotions.

  • "Emotions" is a two-part lecture and we're continuing

  • along certain themes. I want to begin by responding

  • to a question which was raised in the last class concerning

  • smiling and nonhuman primates. It was a very good question.

  • The issue was: we know that humans have

  • different sorts of smiles to convey different sorts of

  • information. The question was,

  • "do nonhuman primates, like chimpanzees or gorillas or

  • gibbons, have the same many sorts of smiles?"

  • So, I contacted the world's expert on smiling,

  • who did not return my e-mails. So, I contacted the second

  • world's expert on smiling who told me that the answer is "no,"

  • that primate--nonhuman primate smiles actually correspond

  • almost entirely to appeasement smiles.

  • They're "don't hurt me" smiles. They're equivalent to the "coy

  • smile" that we saw on humans. But that nonhuman primates do

  • not use smiles for greetings; there's no equivalent to the

  • "greeting smile" or "Pan Am smile";

  • nor do they use them as genuine expressions of happiness.

  • There's no equivalent to the "Duchenne smile."

  • That's as far as I know. If the world's expert gets back

  • to me and says something different, I'll keep you posted.

  • Another thing. Going back to the beginning

  • theme of the class, what we started--just to

  • review, we talked about the different functions of emotions.

  • And then we talked about smiling and facial expressions.

  • And then we turned to some--to a nonsocial emotion,

  • the case of fear. And then we shifted to social

  • emotions. And we talked about social

  • emotions towards kin and the special evolutionary reasons

  • that would lead them to evolve. And as we were ending,

  • we were talking about the relationship between an animal

  • and its children, particularly in cases like

  • humans and birds and mammals where there tends to be a close

  • relationship with our children. We invest in quality,

  • not quantity. I might produce very few

  • children in my life. And my evolutionary trick then

  • is to focus very intently on them and make sure they survive.

  • If I were to produce 100 children, I could stand to lose

  • a few, but if I just produce five in my lifetime or two or

  • one, they become very precious to me.

  • And so, the story of the evolution of a species like us

  • involves a long period of dependence and deep,

  • deep bonds between the parent and the child.

  • And that's part of what I talked about,

  • how parents respond to children.

  • And I want to begin this class by giving an illustration from a

  • documentary about parental response to children,

  • but I want to give it in a species that's not us.

  • And here is why. I'll explain why with an

  • analogy. I have a friend of mine who

  • studies the psychology of religion.

  • He studies why people hold religious beliefs.

  • And he tells me that when he's talking to a non specialist,

  • somebody not in the field, he doesn't ever tell them,

  • "Yeah, I'm really interested in why people believe in the Bible

  • or why people light the candles on Sabbath or why people go to

  • church" because these are religions that people around

  • here hold, and if you tell people you

  • study them they'll sort of be puzzled, "why would you want to

  • study something like that" or offended.

  • If you want to talk about the psychology of religion to an

  • audience like this, what you do is you start with

  • the exotic. So, you start by talking about

  • people who put butter on their heads.

  • Dan Sperber talks about a culture where the men put butter

  • on their heads in the summer. And it kind of melts and that's

  • part of--one of the things that they do or--you talk about a

  • culture that believes in spirits or that trees can talk.

  • You say you're studying it and they say, "Oh,

  • that's interesting. I wonder why they believe that?"

  • And you use that as a way to look at more general facts that

  • exist even in our culture. You use the fact that we don't

  • take the exotic for granted as a way to motivate the scientific

  • study of things we do take for granted.

  • And this is, of course, true more generally.

  • This was the point in the William James quote when he

  • talked about things that are natural to us and noticed that

  • some very odd things are equally natural to other species.

  • And it's true, I think, in particular when we

  • talk about things like the love we have for our children.

  • So, one way to look at the love we have for our children

  • scientifically, isn't to look at it head-on,

  • because the love we feel towards our own children feels

  • sacred, it feels special, but look at it in other species.

  • And so, one of the nicest illustrations of this is the

  • Emperor penguin, which was--which--whose

  • childcare and mating practices were dramatized in a wonderful

  • movie called "March of the Penguins."

  • And this is interesting because they had this incredibly

  • elaborate and quite precarious system of generating and taking

  • care of offspring. So, I want to show you a brief

  • clip of the movie to illustrate some parts of this.

  • What they do at the beginning, which is not--which leads up to

  • this, is they take a very long trek from the water to their

  • breeding grounds. Their breeding grounds is--are

  • protected from the wind and they're on a firm piece of ice

  • so they could hold the whole pack.

  • They do the breeding there and it's there that the eggs are

  • created. So, this is where the movie

  • begins at this point. "March of the Penguins" was the

  • second best--second most popular documentary of all time,

  • beaten only by "Fahrenheit 9/11."

  • And people responded to it in different ways,

  • which are informative when we think about the generalizations

  • you could make from animal behavior to human behavior.

  • Some conservative commentators saw this as a celebration of

  • family values, such as love and trust and

  • monogamy. Some liberals,

  • who hate everything that's good and true, [laughter]

  • responded by saying, "Well, yeah,

  • they're monogamous for one breeding season.

  • It's a year. Then they go and find another

  • mate. If you add it up,

  • it's pretty slutty." [laughter]

  • I think more to the point, people were impressed and

  • stunned by the rich and articulate and systematic

  • behavior that these animals were showing.

  • Plainly, they didn't pick it up from television,

  • movies, culture, learning, schooling,

  • and so on. To some extent,

  • this sort of complicated behavior came natural to them.

  • And it's understandable that some proponents of intelligent

  • design, or creationism, pointed to this as an example

  • of how God creates things that are deeply, richly intricate so

  • as to perpetrate the survival of different animals.

  • From a Darwinian standpoint, the Darwinian would agree with

  • the creationist that this couldn't have happened by

  • accident, this is just far too

  • complicated, but would appeal to the--to this as an exquisite

  • example of a biological adaptation,

  • in particular a biological adaptation regarding parental

  • care to children shaped by the fact that children share the

  • parents' genes and so parents will evolve in ways that

  • perpetrate the survival of their children.

  • Then there's the other direction, which is how children

  • respond to parents, how the young ones are wired up

  • to resonate and respond in different ways to the adults

  • around them. And we quickly talked about

  • some different theories of this. And I'll just review what we

  • talked about last class. Babies will develop an

  • attachment to whoever is closest.

  • They'll usually prefer their mothers because their mothers

  • are typically those who are closest to them.

  • They'll prefer her voice, her face, her smell.

  • It used to be thought that there is some sort of magical

  • moment of imprinting that when the baby is born,

  • the baby must see his or her mother and "boom," a connection

  • is made. If the baby doesn't,

  • terrible things will happen with attachment later on.

  • This is silly. There is no reason to believe

  • there's some special moment or special five minutes or special

  • hour. It's just in the fullness of

  • time babies will develop an attachment to the animal that's

  • closest to it. They will recognize it as,

  • at an implicit level, at an unconscious level,

  • as their kin. Well, how does this work?

  • How does the baby's brain develop--come to develop an

  • emotional attachment to that creature?

  • Well, you remember from Skinner that operant conditioning could

  • provide a good answer to this. And this is known as the

  • "Cupboard Theory," which is babies love their moms because

  • their moms provide food. It's the law of effect.

  • It's operant conditioning. They will approach their

  • mothers to get the food from them.

  • And they will develop an attachment because their mother

  • provides food. And this is contrasted with a

  • more nativist, hard-wired theory developed by

  • Bowlby which claims that there's two things going on.

  • There is a draw to mom for comfort and social interaction

  • and fear of strangers. Now, in the real world,

  • it's difficult to pull apart these two means of attraction

  • because the very same woman who's giving you comfort and

  • social interaction is also the one giving you milk.

  • But in the laboratory you can pull them apart.

  • And that's what Henry Harlow did in the movies you saw last

  • week. So, Harlow exposed primates to

  • two different mothers. One is a wire mother.

  • That's a Skinnerian mother. That's a mother who gave food.

  • The other is a cloth mother set-up so that she'd be

  • comfortable and give warmth and cuddling.

  • And the question is, "Which one do babies go for?"

  • And as you can remember from the movies, the results are

  • fairly decisive. Babies go to the wire mother to

  • eat--as one of the characters said, "You've got to eat to

  • live." But they viewed the--they loved

  • the cloth mother. They developed an attachment to

  • the warm, cuddly mother. That's the one they used as a

  • base when they were threatened. That's the one they used as a

  • base from which to explore. Okay.

  • And that actually--Oh, that's just--I have a picture.

  • And that actually takes me to the--Oh, except for one thing,

  • it almost takes me to the end of the question of our emotions

  • towards kin. One question you could ask is,

  • "What if there's no contact at all?"

  • Now, you could imagine the effects of how--A lot of people

  • are interested in the question of the effects of the child's

  • early relationship to adults around him or her in how the

  • child turns out later. This becomes hugely relevant

  • for social debates like daycare. So for instance,

  • a lot of psychologists are interested in the question,

  • "Is it better for a child to be raised by a parent,

  • usually a mother, or does it make a difference if

  • the child goes to daycare? What if the child goes to

  • daycare at six months? What if the child goes to

  • daycare at two years? How does this affect the child?"

  • The short answer is, nobody really knows.

  • There's a lot of debate over whether or not there are subtle

  • differences and it's deeply controversial.

  • But we do know that it doesn't make a big difference.

  • We do know that if you got raised by mom,

  • or perhaps mom and dad, or maybe just dad all through

  • your life until going off for school and I--my parents threw

  • me in a daycare at age three months--it's not going to make a

  • big difference for us, maybe a subtle difference

  • though it's not clear which way it would go.

  • But it won't make a big difference.

  • But what if there's no contact at all?

  • What if--What about terrible circumstances where people get

  • no cloth mother, they get nobody for attachment?

  • This is a really--In the real world, of course,

  • you can't do experiments on this.

  • And in the real world with humans, this only happens in

  • tragic cases. But this has been studied.

  • So Harlow, again, raised monkeys in solitary

  • confinement so they were raised in steel cages with only a wire

  • mother. In other words,

  • they got all the nutrition they needed but they got no

  • mothering. It turned out that you kind of

  • get monkey psychotics. They're withdrawn.

  • They don't play. They bite themselves.

  • They're incompetent sexually. They're incompetent socially.

  • They're incompetent maternally. In one case,

  • one of these monkeys raised in solitary confinement was

  • artificially inseminated. When she had a child she banged

  • its head on the floor and then bit it to death.

  • So, you need to be--you need--This shows--This is kind

  • of a stark demonstration that some early connection,

  • some early attachment is critical for the developing of a

  • primate. Obviously, you don't do these

  • experiments with people but there are natural experiments,

  • humans raised in harsh orphanages with little social

  • contact, and these children--If the--In other words,

  • they get fed, barely, but nobody picks them

  • up and cuddles them. These children,