Baby's first understandings
How do we come to understand things at all? How does a baby begin to grow and process information that lets them understand the world around us? Well, Sarah Gerson from the University of Cardiff joined Adam Murphy and Katie Haylor in the studio to talk about exactly that...
Sarah - It's a really good question because of course babies can't tell us what they're thinking, which makes it a little bit more difficult than just asking an adult what they're thinking about. So over the years, we've come up with a lot of really technical and controlled techniques to figure out what a baby's thinking based on very simple processes. So things like where they're looking, how long they're looking at things and what they're doing. So do they imitate what someone else is doing? Do they copy the goal of someone's behavior? Do they look at what they're doing at the time that they're doing it? Or did they predict what that person's going to do next?
Adam - And then using those techniques, how do we then learn to understand the world around us? What kind of things have you found?
Sarah - Yeah, so we've looked at a few different ways that infants first come to understand other people, their goals and their actions, and some of the most important things involve their experiences in the world. So as infants become able to produce more actions themselves, for example, they learn to understand that other people have goals when they perform those actions.
Adam - What kind of experiments do you run to learn that kind of thing?
Sarah - An example of this was a study that I did - too many years ago now - with three month old infants, and at three months of age infants aren't really able to kind of control their actions very well yet. But we gave these three month olds what we called sticky mittens. So we put little mittens on their hands that had Velcro on them and we gave them toys that also had Velcro on them. So this allowed these three month olds to move around those toys in a way that was kind of intentional and goal directed. So this gave them their first opportunity with performing these kinds of actions that they could control themselves. And then we tested their understanding of someone else's reaching action in what we call a visual habituation paradigm that's based on how long infants watched different events. And what we found was that when infants had this experience, just a few minutes really, of performing these object directed actions themselves, they then understood those actions as goal directed when they saw someone else performing a reaching action, more so than if they had just watched someone perform those actions without gaining that experience themselves.
Adam - So it's sort of a case of monkey-see-monkey-do in a way, if we see someone do a thing and then we do it ourselves, we understand it better
Sarah - Quite a bit. It works kind of in both directions. So we talk about imitation as being really important. So infants and children will often copy what they see adults doing, but in some cases they often need to perform an action themselves before they can understand what an adult does in order to copy it.
Adam - And then as we start to get older, what kind of milestones do we hit in terms of understanding the world? Like, you know, baby's first understanding of a sentence kind of thing.
Sarah - Yeah. So one of the classic ones we talk about in terms of social cognitive development - so understanding other people - is something called false belief and classically, this has been thought to emerge around four years of age. Although there's some evidence that this might be the case younger now. And what it involves is children understanding that other people have knowledge, beliefs, and thoughts that might differ from our own. So you can imagine that if you kind of play tricks on a child, they have to know that you know something they don't know, and you get all these kinds of levels of understanding. And by about four years of age, classically children are thought to be able to recognise that someone can believe something different from themselves and have a different knowledge state.
Adam - How does that work before that then, do they think everyone around them is just bigger hairier versions of them?
Sarah - It's a really good question. They start to understand some things about how people differ from them earlier. So we know for example, by about 18 months of age, they know that not everyone likes the same things as them. So there's a classic study where infants are given for example, goldfish crackers, which are really popular in the US, and broccoli. And almost all toddlers prefer the goldfish crackers to the broccoli. But they meet an experimenter who tells them that she likes the broccoli and not the goldfish crackers, and really young infants will still give her the goldfish crackers, assuming that's what she wants, because why wouldn't she, that's what they want! But by 18 months or so, infants recognise that someone might like something different from them. And so they give her the broccoli knowing that that's what she wants. So they start to slowly understand how people differ from them, but it gets increasingly complex as they get older.
Katie - Sarah, can I just jump in with a question? Does this relate in any way to empathy or understanding someone's point of view, you know, when little ones are so little.
Sarah - Yeah, absolutely. So understanding other people's thoughts is a lot like understanding other people's emotions, right? And so you can't understand that someone feels different from you before you can understand that they might think or know something different from you. So they tend to emerge around the same time. And there's a lot of research looking at whether and how they're related in children.
Adam - And then knowing all these things and doing all these experiments, can you diagnose any difficulties these children might go on to have?
Sarah - Yeah. So the most classic example of this is autism spectrum disorder, which is known to have what we call social communicative disorder, or problems with these kinds of skill sets. And so we can see if children don't perform as well on these, this might be a sign that they have issues on this kind of spectrum of disorders.
Katie - Sarah, just going back to the milestones thing - I'm trying to separate in my head understanding of language from understanding of tone of voice, even when infants can't understand the words, I guess they pick up on tone, right?
Sarah - Yeah, absolutely. We actually just did some research on this at Cardiff University last year, looking at whether infants can recognise what we call controlling or supportive tones in speech toward them. But really classic research that's been replicated a lot of times looks at the fact that infants prefer what we call infant directed speech. So sometimes people refer to this as 'motherese' where it's kind of exaggerated and high pitched that people almost automatically use when they're talking to infants or even pets sometimes. And we know that infants can tell the difference and prefer to listen to this kind of tone, more so than what we call adult directed speech, so kind of how we're talking now, really early in life. So they can tell the differences in tone before they understand what the words are that are involved in that.
Katie - I'm really reassured that you said that because I've just got two kittens and I'm always kind of making goo-goo noises at them and I thought 'oh, do they find that really annoying?' But what you're saying is infants do like that kind of communication.
Sarah - At least the human infants! I don't know if anyone knows about the animals, but I know that my dog is really annoyed now that I have a human child, because we use the same voice with them both.