JO4L*pZ A`KB*k1AA0Professor 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.
{:X)y0x4qri.DB/x0I 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.心理学空间+kP@X*|)^
9[,zR/q-U%wh0We 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.
;k"r6tOg X0And 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. [clip playing]
z]I;j+j0"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]心理学空间BSG6t$~%bA7N
mY A:pjH"Fz0I 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.
G*hk9` ~XI0Then 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.
c(e!DN4u`L0Okay. 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.
AE,Wa$]-E{t0But 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.
)VWl ~8Y4A)WEqV Ny0Obviously, 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, if this happens for long enough, they end up with severe problems with social and emotional development. From an emotional point of view, they're often insatiable. They really need cuddling and support or they're apathetic, they don't care at all. Now, there's some sort of good news, which is if you get these people or these monkeys early enough you can reverse the effects of this bad development. So, there's some research done with monkey therapists. So then, what they do is they take the monkey, they raise it in a steel cage, the monkey comes out, the monkey is kind of psycho, and then they send in a younger monkey who is just goofing around, jumping all around the place and everything. And experience with this younger monkey who just follows them around and clings to them leads to gradual improvement. It makes the solitary monkey become better.心理学空间-n^0BK~9U
b"EM K4X:mbJL0There might be a similar effect with humans. So one story more about--of an anecdote than an experiment was a situation where at the age of one and a half, children were taken away from a really harsh orphanage where they had no contact and brought into a home for mentally retarded women where these women gave them plenty of contact and cuddling and apparently, from what we know, brought them back to normal. And this is all I want to talk about, about the emotions we feel towards our kin, towards our children, and towards our parents. Any questions or thoughts? Yes.心理学空间 `5Nx xz&b6uh
Student:Do children in orphanages comfort each other?
mf#M%`w W0Professor Paul Bloom:It's a good question. Do children in orphanages comfort each other? I don't know. The situation probably wouldn't be there--The problem is children in orphanages who are in these terrible situations tend to be babies and very young and they wouldn't be thrown together in situations where they could comfort each other. It's a really interesting question. What if it was a situation where children were raised without a supportive cloth mother at all, would not be able to pick them up and hold them, but they could play amongst themselves and support each other? I don't know the answer to that.
Teaching Assistant:Yes.
Professor Paul Bloom:Yes? Is there evidence on that?心理学空间$H6@*`;A,~t(c
/K:T C'k/Xw-?;aN8F0Teaching Assistant:Yes, there is. [inaudible]心理学空间1I,a#uRjH)r!|W
Professor Paul Bloom:Yes. [laughter] The answer is there is evidence, [laughs] as everybody knows, [laughter] that this sort of--amongst the young, support can actually help the monkey and the children. Somebody else had a question here? Yes.心理学空间.F:y%\5oj_5u!ze
w a'_)lG3u rN0Student:What does that tell us about the middle ground, if the parent is comforting just a little bit and then not that much [inaudible]
Professor Paul Bloom:Right. So this is--The question is, "What does that tell us about the middle ground?" So this is an extreme case but what do we know about the middle case? Say your parent--You're not raised in a cage, you're not in a Romanian orphanage, but your parents just don't pick you up very much. They don't love you very much. There's no good evidence that that has any effect on a person. The problem is, and we're going to talk about this in much more detail in a couple of weeks, is it's true that parents who aren't affectionate have kids that aren't affectionate but it's not clear this is because of a genetic connection or an environmental connection. The one thing we do know is that in the middle ground, effects tend not to be dramatic. So when you get away from extreme cases, effects are hard to see and require careful experimental research to tease out. I think what it's safe to say for a lot--for everything but the severe conditions is we don't know what kind of effects there are. But if there are effects they are not big and dramatic ones.心理学空间&}Y7\ G ?7ZE
Okay. Animals' good feelings, animals' emotional attraction to their kin, is not a huge puzzle from an evolutionary point of view. Evolution is driven by forces that operate on the fact of how many genes get reproduced and replicated among your descendants. So, it makes sense that animals would be wired-up to care for their kids. It would make sense that kids who are wired-up to survive would develop attachments to their parents. What's more of a puzzle though is that animals, including humans, seem to have exquisitely complicated relationships with non-kin. In particular, animals are nice to non-kin. You are nice to people that you're not related to. There are a lot of examples of this. Animals groom one another. You go, you pick off the lice and the bugs off your friend; they pick it off you. They give warning cries.心理学空间.rVQ&e~4@:q/p:w.X#i
So, warning cries--All sorts of animals give warning cries. You are--I don't know. You're a little animal and a big animal comes charging and you say, "Hey!" Oh. You may sort of cry and everybody runs away. And that's very risky for you but you do it anyway, often to protect people you aren't related to. Often animals share childcare. And from a cold-blooded, natural selection, survival-of-the-gene point of view, you would imagine that if you lend me your kid for the day I would eat him for the protein and "it's not my genes and actually it gives more for my kids." That's not quite how it works though.
Animals share food. In fact, that animal, hugely ugly, the vampire bat, shares food. What happens is the vampire bat--vampire bats live in caves and they fly out. And what they do is often a bat will strike it big. She'll find a horse, for instance, bite the horse, pump in tons of blood and then fly back. And what it does is it doesn't keep it to itself. Rather, it goes around the whole cave and vomits blood into the mouth of all the other vampire bats so everybody benefits. Isn't that nice? [laughter] Now, what you're tempted to say is, "Well, that's really nice. Everybody benefits," but this raises a puzzle from the evolutionary point of view.心理学空间G7\:D P0o
s8NEA t#q0Remember, animals benefit more, and to this situation, animals benefit more by working together than by working alone. The benefits outweigh the costs. This is known as "reciprocal altruism" meaning my behavior to you, my good behavior to you, my altruism for you, is predicated on the idea of reciprocation, "I'll benefit from you." And you imagine how vampire bats, for instance, why this makes sense. This is--If you're a vampire bat, it's a better system when anybody strikes it big to feed you rather than for anybody who strike it big, use the blood and then spit out all the rest of it. But here's the problem. Here's why it's such a puzzle. The problem is the existence of cheaters. And in economics and sociology these are also known as "free-riders." And what a cheater or free-rider does is it takes the benefits without paying the cost. Imagine two genes. Imagine one builds a vampire bat that accepts blood from others and shares blood. The other gene accepts blood from others and doesn't share blood. In the long run, "B" will actually out-produce gene "A" because in fact, "B" will be healthy while other vampire bats get sick. And then so the offspring will do better.