Professor Eamon McCrory, UCL Division of Psychology and Language Sciences:
What is neuroscience and what do we know about brain development? What challenges do we face and what are the limitations of current research? In this short video, we hear from several leading neuroscientists who reflect on these questions and consider remaining gaps in our knowledge that we still need to address.
Why do we study the brain to understand childhood trauma? (0:25)
Dr Nikolaus Steinbeis, UCL Division of Psychology and Language Sciences:
We study the brain to understand child development for many different reasons. If our starting point is that we need the brain to behave and act and decide in certain ways around the world, then it’s obviously important to try and understand how the brain changes and develops to understand child development. Now one thing that we’ve learnt about brain development is that different parts of the brain develop at different rates. So, for instance, those parts of the brain that are important for vision or for hearing things, they develop relatively early. Whereas those parts of the brain that we need for regulating our behaviour for making plans for following up on those plans they develop relatively late. Understanding those different developmental time courses can help us understand why children behave the way they do and how that changes throughout childhood.
What is Neuroscience? (1:21)
Dr Vanessa Puetz, UCL Division of Psychology and Language Sciences:
Neuroscience is a scientific discipline in which we try to understand the development and also the functioning of the brain, not just a human brain, but also the animal brain. What it allows us, for example, to do is to understand the mechanisms that underlie certain thoughts or, for example, actions such as when you laugh or when you cry. What is really important to realise is that neuroscience can provide a lot of answers about the mechanisms, But it can’t provide all the answers of how we become the person that we are. It’s really important to realise it’s just one piece of the puzzle. We need to look to psychology. We need to look to sociology. We need to look to genetics, as well, in order to provide a full picture of the human development.
What does brain development look like? (2:13)
Professor Pasco Fearon, UCL Division of Psychology and Language Sciences:
When you look at the way the brain develops it’s the most extraordinary kind of orchestra of biological events. Within the womb, it’s already kind of creating itself in a very complex set of interactions between molecules and the environment that the foetus is finding itself within, particularly after birth.
After birth, the way that the brain organizes itself starts to become increasingly influenced by the environment that it finds itself. The way that this seems to work is that the brain generates a huge number of neurons, so even at the point of birth, babies have pretty much the full complement of neurons and they have an enormous number of synaptic connections – the connections between one neuron and another. In fact, they have more than we do as adults.
So, it’s almost as if you begin life with everything in your brain is connected to almost everything else and then, what the environment is doing, is helping gradually to shape those connections, so that the ones that really work and help the child learn are kept, and the others, the less important, gets slowly pruned out, so that it becomes a really efficient information learning processing machine. That process of pruning of synapses towards the task of the child becoming increasingly sophisticated, expert and clever and socially aware, all of those things, are shaped by the environment that child is finding himself in. The brain is like this plastic organ that is constantly responding to the environmental inputs that it experiences and adapting and building and moulding itself to the social environment.
How do we study the brain? (4:02)
Dr Vanessa Puetz, UCL Division of Psychology and Language Sciences:
As neuroscientists, we have a big toolkit available to study the brain of young people and one of the most widely used and safest method is functional magnetic resonance imaging or short fMRI. So what’s important to understand is that in the human brain, especially with young people, but also mostly with adults, we can only measure brain activity or neuronal activity indirectly. That means we need to rely on a substitute measure and in the case of fMRI, this is blood flow. So, it is really a very straightforward, yet brilliant way to look at brain functions. So, imagine you are engaging in a task, such as laughing, so you’re watching a funny cartoon and you’re laughing. The brain area that supports laughing and that supports the comprehension of funny content will need fuel to support this task. This fuel, in the human brain, comes in the form of oxygen and glucose. So, glucose being sugar. And blood, in fact, can carry such oxygen to the brain area where it is needed. What is really interesting is that blood actually has magnetic properties. So, blood that carries oxygen molecules is differentially magnetic and then blood that doesn’t carry oxygen. So, now imagine there is this brain area that is engaged in laughing or helps to support the function of laughing and it needs this oxygen and the blood flow delivers it — drops the oxygen. In this very moment, the magnetic properties change in this particular area. Now, if you have ever seen an fMRI machine, it is this it’s like a huge circular machine that is in fact nothing but a magnet. This powerful magnet allows us to detect these subtle changes in blood flow in the brain. What is most important, I think, for everybody to know, is that this has nothing to do with x-ray. It’s a very safe method and it is so safe, in part, because it doesn’t involve any harmful radiation. So, this is why we can use this machine or this method to work with young people and also to conduct repeated measurements.
Is it really neuroscience? (6:29)
Dr Nikolaus Steinbeis, UCL Division of Psychology and Language Sciences:
There are a few questions that we should ask when someone makes a claim about neuroscience. I think the first, and probably most important one, is whether that claim is based on a scientific study that’s been published. So, scientific publication is the one way in which we can ensure that the science is really solid because it undergoes peer review. Our peers read it and they comment and they say whether this actually passes certain criteria. So, that’s a really important first question that you need to ask, is whether this is based in a scientific result. And then there are some follow-up questions that you would need to ask in terms of, was the research done in humans? Sometimes studies are being done on animals and that’s obviously a very different kettle of fish. The next question is – was the research done in children? And what kind of experiences did those children have was maltreatment, for instance, involved? Of course, if you want to understand any particular changes in the brain as a function of maltreatment. You also need to have a control group — basically children that haven’t experienced something like maltreatment because only those types of studies really allow you to make a strong inference based on the neuroscience behind it. Just because there’s a picture of a brain involved in any report of a finding, we need to be really mindful to actually question that finding nonetheless. I think there are so many things that neuroscience can tell us and we need to be quite careful and very critical of what it can and can’t tell us.
The future of neuroscience research (8:05)
Dr Vanessa Puetz, UCL Division of Psychology and Language Sciences:
I think research in the future will have to take us down a longitudinal road. So, what we are currently doing or what we have been doing is we have been looking at snapshots of these young people in time. So, we have been doing what is called a cross-sectional study. So, that means we’re just looking at these young people, at this moment in time, and see if the early experiences have had some impact on brain development right now. But, what we really want to know and what is still absolutely unclear, is how does how does brain development move on from here? So, we should actually follow these young people into puberty, into adulthood and conduct what is known as a longitudinal study. It is in fact the case that the majority of young people who have experienced maltreatment do not go on to develop severe psychological health issues or mental health issues. This really raises the question – at which point does this change? So, what are the factors that promote such change? For example, we should be having a look to what happens in puberty. So, does social support play a role, in making sure that these people bounce back from those difficult experiences? But, all of these are questions that we can only answer if we follow these young people for a longer time span, rather than just looking at them at one single time point.