Smart Drugs, Anyone?
We find out exactly what is going on in the brain during the teenage years. Plus we ask should we all be taking drugs to make us 'smarter'? And we find out about wiring up bats for neuroscience research and beating addiction with positive messages.
In this episode
00:54 - What’s going on in the Teenage Brain?
What’s going on in the Teenage Brain?
with Professor Sarah Jayne Blakemore, University College London
Hannah - Now, Harry Enfield's infamous sketch on Kevin's 13th birthday provides a comic take on what it is to become a teenager.
The clock strikes midnight and Kevin loses the power of rational thought and speech and he becomes the parody of a moody stroppy teenager, embarrassed by everything that his parents do, and finding everything just 'so unfair'.
This entertaining extreme take on adolescence is being scrutinised by the scientists. We speak with Professor Sarah-Jayne Blakemore who studies teenage brain at University College London.
Sarah - It's only really recently that we've known that the adolescent brain changes so much. Up until about 15 years ago, scientists just didn't really have a clue about what was going on in the adolescent brain.
And so, these stereotypical adolescent behaviours, (although note, not all teenagers behave like Kevin, but some do) were mostly put down to kind of hormonal changes or social changes.
But research in the last 10 or 15 years, mostly using magnetic resonance imaging (or MRI) scanning has enabled scientists to look inside the living developing brain at all ages and to track changes in both the structure of the brain, so its organisation, and also, how it functions, across their lifespan. So, there is now actually a vast amount of research on the adolescent brain. This research has just completely taken off in the last decade, but if I just focus in on a couple of key findings:
One of the brain regions that undergo the most protracted development in humans and during the adolescent period is called prefrontal cortex. So that's part of the brain right at the front of your head and prefrontal cortex is disproportionately bigger in humans than in any other species. And actually, it's involved in a whole load of higher cognitive functions that are much more sophisticated in humans than in any other species. So things like decision making, planning what you're doing this evening or next week or even next year.
The prefrontal cortex is also involved in inhibiting inappropriate behaviour, so stopping ourselves, taking risks for example. It's also involved in understanding other people, so social cognition, and also, self-awareness.
Now, we know from many different magnetic resonance imaging (MRI) studies on thousands and thousands of children and adolescents that the prefrontal cortex undergoes really quite profound changes during adolescence.
So we know for example that in terms of structure, grey matter volume - so grey matter contains brain cell bodies and connections between brain cells called synapses and we know that in a human brain, in a human prefrontal cortex, grey matter increases during childhood. Peak grey matter volume occurs in early adolescence - a couple of years later in boys compared with girls, so around age 11 in girls and 13 and boys probably because girls go through puberty a couple of year earlier than boys, and then decreases during adolescence. So in other words, there's quite a large loss of grey matter in the prefrontal cortex during human adolescence, and that might sound bad, but actually, it's a really important process.
We think it partly reflects the loss of excess connections which is a process known as synaptic pruning. And synaptic pruning is a really important process, so it's partly dependent on the environment and that connections or synapses that are being used are strengthened, and synapses that are not being used in that particular environment are eliminated. They're pruned away.
Hannah - So, the necessary pruning or removable of surplus connections in the prefrontal cortex during adolescence might explain some of the behavioural changes associated with the teenage years. There's also a second line of inquiry, measuring how the activity of the brain changes whilst teenagers are doing different tasks, and having their brain scanned using functional magnetic resonance imaging. There's a huge amount of research coming out now in this area. Sarah explains some of her recent results.
Sarah - In my lab, we're particularly interested in the social brain, that is the network of brain regions that are used to understand other people. So for example, to understand other people's minds, their emotions, their mental states, their intentions, that kind of thing. And what we tend to find is that during adolescence, there's a change in which the social brain functions.
So, it's not that adolescents and adults are using completely different regions of their brain to understand other people. They're not. In fact, they're using more or less the same network of regions, but there's a change in the level of relative activity in the different regions of the network. And one of these findings that we've replicated several times and other people, what the labs around the world have also found is that there's a decrease in the level of activity in a part of the social brain called the medial prefrontal cortex.
So in other words, adolescents use the mid or prefrontal cortex more than adults do to do exactly the same kind of social cognition tasks involves thinking about other people's minds or emotions or intentions. And we think this might be because adolescents and adults use a different sort of mental approach, a different cognitive strategy to make social decisions, and that's a question that we're now particularly interested in looking at.
Hannah - And Sarah's lab has been doing some neat experiments and found that some social brain areas undergo maturation in association with how many years the people have been alive whereas other areas mature more in association with how far along in puberty they are.
Sarah - This is the best study of its kind and now, we're trying to figure out why, what causes the differences in these two regions.
Hannah - That was Professor Sarah-Jayne Blakemore from University College London, speaking about a new area of neuroscience of how the brain changes during the teenage years. These findings could help to inform educational policy.
07:11 - A Researchers Pick of Neuroscience News
A Researchers Pick of Neuroscience News
I'm sitting with David Weston, PhD student at Cambridge University who's been scouring the neuroscience journals for his top 3 papers of the month.
David - So let's start with a paper that was published in the journal Nature that looks at how your genes can affect your risk of getting Alzheimer's disease.
A group of scientists in Iceland, collaborating with people all over the world, have discovered that a small mutation in one of your genes can dramatically reduce your likelihood of getting Alzheimer's.
Hannah - So, it's a mutation in a gene that actually reduces the risk of Alzheimer's. A beneficial mutation?
David - Yes. The mutation is in the β-amyloid precursor protein which has been shown in previous studies to be involved with Alzheimer's disease. If you compare the brains of a healthy person and someone with Alzheimer's one of the most striking things is that Alzheimer's patients have large deposits of β-amyloid protein throughout the brain. This causes a whole host of effects including memory loss.
This new mutation however, appears to protect against these deposits, giving the person with the mutation a much lower risk of developing Alzheimer's disease and the memory loss associated with it.
Hannah - And is this a combination of human's observational studies and also, scientists looking at cells growing in a petri dish?
David - The initial study was done with humans and looking at their genetic sequencing, but they also did a range of laboratory techniques that looked In Vitro to see the effect of the mutation. And they found that with this mutation, the toxic production of beta amyloid was actually reduced.
Hannah - So, this paper really demonstrates that a mutation in a particular gene can help us to understand more about Alzheimer's, what's going on in the cell biology of Alzheimer's and may potentially lead to a new treatment for Alzheimer's as well.
David - Second exciting paper - lots of people are studying how we can use technology to help restore function for people who have lost the use of their limbs, either as a result of accident or disease, and the scientists who wrote the next paper have opened up the field with their recent publication in the Journal of Neural Engineering.
The researchers from Imperial College London have developed a pair of glasses that allows a person to control a computer using only their eyes. Previous efforts to deliver these kinds of technologies to people has been hampered largely by their cost and their accuracy but the authors of this paper have managed to build their interface using cheap components from video game consoles.
David - Yeah, so there have been quite a few studies that have looked at these kind of interfaces, but the advantage of this system is that it actually cause a significantly less amount of money compared to these previous studies, and also, the accuracy has been massively improved.
Hannah - And how have they managed to do that then - improve the accuracy and also decrease the cost of this technology?
David - So what they've done is they've actually used cheap components from video game consoles to trap the movements of the eyes using small cameras. So, by tracking these eye motions, the wear of the glasses control a computer to do many things like play games browse the internet or even send emails. And so, this remarkable technology can extrapolate not only where the person is actually looking, but because it works on both eyes, it can also tell at what distance their looking at. And this opens up a whole world of possibilities for what this technology can be used for, and it allows people to interact with a 3-dimensional environment rather than just a 2D one.
Hannah - Fantastic! So, that's a neat example of how technology arising from play can actually go and help patients.
David - Yeah, definitely. And indeed, in the paper, they actually had a link to a video which showed them playing a 3D game on a computer which is quite a neat way to show how the device works very well.
David - So, in this last paper, scientists have shed some light on how stress can lead to post-traumatic stress disorder (PTSD) and we all know that fear and anxiety are essential parts of our lives because they teach us to not take a necessary risk and to avoid dangerous situations. But sometimes, anxiety is so intense that it actually prevents people from getting on with their daily lives. And in this new paper, the scientists presented data that showed these molecules called dynorphins play a role in suppressing anxiety in the brain
Hannah - So how did they look into this dynorphins and the role of them in terms of fear and anxiety then?
David - So what they did was they created a genetically modified strain of mice which actually lack the gene to produce these dynorphins and they tested them in a variety of laboratory situations to test how fearful and anxious they were. And they found that these mice that didn't have the dynorphins gene actually showed significantly increase fear response and anxiety response after being tested compared to normal mice.
Hannah - And is there any correlation between these dynorphins and human patients that may show enhanced anxiety or post-traumatic stress disorders?
David - Yes. The authors of the study actually had to look at human subjects and found that there are natural variations in the level of dynorphins in people's brains and they found that with people with lower levels of dynorphins remained more anxious after a painful stimulus was delivered to them compared to those that had high levels of dynorphins after a fearful stimulus. So this really indicates that the dynorphins are a natural anxiety-relieving mechanism that the brain uses.
Hannah - So, it seems these results could help piece together some sort of treatment for people suffering from post-traumatic stress disorder, using natural anxiety systems already existing, but probably not properly functioning in their brains.
Thanks to David Weston, PhD student at Cambridge University.
12:25 - Neuroscience NewsFlash
Force of habit under stress
Schwabe and colleagues at Ruhr University and University Hospital Bergmannsheil have discovered why stress makes people more likely to lapse back into old habits. The team used drugs to bring about stress in volunteers. They then examined their brain activity using functional MRI scanning whilst asking the stressed volunteers to perform tasks and choose a reward, say, either oranges or chocolate cake. Published in the Journal of Neuroscience, the results show that the interaction of the stress hormones, hydrocortisone and noradrenaline shut down the activity of brain regions for goal-directed behaviour and make people choose their favourite item, say, chocolate cake even if they've already had their full of it.
Schwabe et al., Preventing the Stress-Induced Shift from Goal-Directed to Habit Action with a β-Adrenergic Antagonist. The Journal of Neuroscience, 31(47): 17317-17325; doi: 10.1523/JNEUROSCI.3304-11.2011
Wiring up bats for neuroscience research
Yovel and colleagues at Tel Aviv University are for the first time, fitting bats with GPS. Since humans rely on vision, we can't accurately measure when something is perceived. But, because bats rely on highly tuned and precise eco location, emitting sonar calls that can be recorded and analysed, we have a window into perception and time coding. Results are coming in which could inspire future developments in robotic sensors and sonar technology, with developments already published in Science and PLoS Biology.
Yovel et al., Active Control of Acoustic Field-of-View in a Biosonar System. PLoS Biol 9(9): e1001150. doi:10.1371/journal.pbio.1001150
The lies have it
No evidence for lie eye movement link. Since the 1960s, practitioners have been taught that when right-handed people are visualising made-up events in their mind's eye, they tend to look upwards and right. Recalling a real memory is claimed to be signalled by looking to the upper left. But this month, University of Hertfordshire researcher Richard Wiseman and colleagues conducted a series of blind experiments which provide considerable grounds to be sceptical of this old notion, and that study was published in PLoS one.
Wiseman et al., The Eyes Don't Have It: Lie Detection and Neuro-Linguistic Programming. PLoS ONE 7(7): e40259. doi:10.1371/journal.pone.0040259
Do 'Smart Drugs' really exist?
A new drug appears to be hitting the UK classrooms. Students are increasingly buying, over the internet, off prescription drugs to help with their exam revision. They're called 'Smarter Drugs' or cognitive enhancers and 16% of American students, and 1 in 10 students here at Cambridge University, have admitted to taking these drugs.
A number of questions about these drugs have come in from our listeners via Facebook and I visited Professor Barbara Sahakian at Cambridge University to get the answers. Barbara - These drugs do exist. They're called cognitive enhancing or smart drugs, and we have a number of different kinds of these drugs.
So for instance, I help to do the proof of concept studies for the drugs which are cholinesterase inhibitors. Those drugs are to boost acetylcholine in the brain and improve cognition in patients with Alzheimer's disease and they're currently now used as treatments and approved by NICE (The National Institute for Health and Clinical Excellence is a special health authority of the English National Health Service).
And they help boost really attention and concentration, and they frequently keep patients functioning at their best level. Then we have other drugs that might boost the chemicals in the brain called dopamine or noradrenaline, those neurotransmitters, and those are drugs such as methylphenidate or Ritalin as we know it, and those are used frequently in the treatment of ADHD (attention deficit, hyperactivity disorder), and they are very beneficial.
We've done studies here at Cambridge showing that even if you're a healthy volunteer, you can find enhancement of different forms of cognition using these drugs like methylphenidate or Ritalin and there's now a newer drug called modafinil which was licensed in about 1997 as Provigil for narcolepsy which is excessive daytime sleepiness. And that is being increasingly used by healthy people as a lifestyle drug.
Hannah - And how are they exactly improving cognition in these healthy volunteers?
Barbara - With our studies in healthy humans with modafinil, we have actually seen improvements in forms of executive function, but also on a pattern recognition memory test. So, on memory tests, we've seen improvements. And the interesting thing is that it doesn't take much for a small improvement and one of the forms of cognition to have a knock-on effect across a wide range of function. So for instance in 2008, there was the Academy of Medical Sciences report and that stated that even a small 10% improvement on a memory score might lead to a higher A level grade or degree class. So there's quite a lot to play for here, and so, there's a lot of neuro ethical issues too about coercions and student use of these drugs when they're not actually got a neuropsychiatric disorder such as attention deficit hyperactivity disorder.
19:27 - A'Level Students discussing 'Smart Drugs'
A'Level Students discussing 'Smart Drugs'
with Students at Jack Hunt School
The Naked Scientists don't just sit in the buff in the studio interviewing scientists. Oh no! we also get dressed and visit schools across the UK to discuss science with students. And as part of a Wellcome Trust Society award, we visited schools to discuss a new drug trend that appears to be hitting the UK classrooms.
Students are increasingly buying, over the internet, off prescription drugs to help with their exam revision. They're called 'Smarter Drugs' or cognitive enhancers and 16% of American students, and 1 in 10 students here at Cambridge University, have admitted to taking these drugs.
Here are some of the students that we've been discussing the drugs with:
John, Natasha, James, Jordan
Hannah - So these are 17-year-old A'Level students from Nene Park Academy in Peterborough, letting us know their thoughts. The first question that I asked them was: Would you take these drugs?
James - Well, we don't really know the side effects. So, if we knew the side effects and they were mainly good then yeah, I would probably go with it, but if there were side effects like decreased age expectancy, when you come off the drug, there's less cognitive brain function then I would just go, no.
Hannah - And you're in a definitely, "No, I wouldn't be taking these cognitive enhancers" camp. Why is that?
John - Well, I think if you're going to be taking this sort of thing, it's not going to be you that's getting the good grades. It's going to be you plus these drugs. It's not you as a person. It's not who you are. It's just this performance has been put on you by the drug that you've taken, and if you went to a higher level and you're expected to perform at a level later in life, after the exams, you couldn't actually perform because you've taken the drug.
Hannah - So, it may affect your later life for example. You might feel that you've got to take the drug if you go into a university and for work performance.
So, you're in the, "Yes, I would be taking the drug" camp and in some ways, you're being accused of almost cheating.
Jordan - This whole argument is based upon that idea that this drug will be helping you in your exam results. But the same can also be same for caffeine and coffee. Everyone takes coffee during the day to help them stay awake throughout the day, to perform better, and this drug would just be helping you to stay awake for the night, soak in more information up, and benefit you in your exams.
Hannah - So there's no difference between these cognitive enhancers and traditionally used stimulants like caffeine, or exercise, or Red Bull for example, and it's not actually cheating. It's using something that's actually there.
I'm getting people that are kind of, "Uhh!" So, I'm going to turn back to your counter argument to that.
John - Well, if you think that it's the same as caffeine or any other stimulants there then I don't think that's a reasonable argument you're looking at because if you look at caffeine for example, it's widely used across communities, and I don't think it's the intent that you're wanting to do better in your exams, so you take caffeine.
You drink it because it's there for enjoyment purposes and if you're going to have this drug available, I think people would take it with intent to help them with their exam results. So, it's more of a thing that you want to do for an output that you want to get from yourself.
Hannah - So, moving on to the next point, would you allow, for example, your children to take these drugs and what do you think about people your age or even younger, taking these tablets?
Natasha - It depends on the long term effects because at a young age, the brain is still developing, so it could interfere with this development, and it could either interfere with it negatively or it could also interfere with it slightly positively as well.
Hannah - So, at the moment, we don't have much information on these drugs, so we don't know what might happen in terms of the plastic nature of the brain and how these drugs might affect them in a long term.
James - 15 years isn't really long enough to explore the long term side effects. You need to go 40 or 50 years for that where this drug could improve your baseline cognitive ability or decrease it, we don't know.
So, if they were to increase it, I would actually let my children take it because there wouldn't be side effects, it wouldn't be really bad. They would improve them later in life and they would actually become a better person.
Hannah - And what do you think would happen to society if the government, for example, put this as a supplement into our drinking water like they do with fluoride. So, if everybody in the UK or everyone in the world was taking these cognitive enhancers, do you think that might have widespread social implications? What might happen to our society?
John - Well, I think if everybody took these drugs, it wouldn't change the intellect or performance that we've got at the moment. It would just sort of shift people upwards as a whole collective group, which I think could have a possibly positive effect. However, as long as we had extensive research into side effects and things that would go on if you do take the drug.
I mean, if you've taken the drug and it's boosted everybody up, then obviously, that's going to be positive because it's going to have an effect upon the community, the economy, and the business sector, and everything that we're doing. I mean, research even would go to a higher level because we've given this performance enhancing type thing that we've got.
Hannah - Okay, these cognitive enhancers actually, although they're shown to improve attention and ability to retain information, even so, well, we don't know - they may have a negative impact on creativity and innovative thinking. So, do you think that might affect society?
Natasha - Yes, it could affect society if there's no longer creativity because it would mean basically, you could end up with no new ideas, just the same thing being repeated again and again which would lead to almost like a stagnation effect.
Hannah - A stagnated society.
James - But if you did reduce creativity, we'd basically just have a race of robots. Everyone would just be conformed to one way of thinking. But if it didn't reduced= creativity, then our race would just flourish.
It would become a really intelligent race, loads of ideas that are new, innovative. We could actually higher ourselves up, but as John said previously, it could raise ourselves another level, but we don't know how people would react to it. It could conflict with people whose genetic makeup we don't know actually. So, people do go by different levels, people could go down. There's just not enough research or information about it.
Hannah - So now, I'm going to ask you for maybe one or two words that you think describes these cognitive enhancers from what you've heard today and what you've been discussing as a group today.
John - I would definitely say, mysterious and artificial.
Natasha - Unknown.
James - Intriguing.
Jordan - Possibly beneficial.
Hannah - And that was Year 12 students from Nene Park Academy in Peterborough, discussing "Smart Drugs'.
25:23 - A Society on Smart Drugs?
A Society on Smart Drugs?
with Dr Iain Brassington, Manchester University
I asked somebody who studies medical ethics for his thoughts on Smart Drugs.
Iain - I'm Dr. Iain Brassington and I'm a Biophysicist based in the School of Law at the University of Manchester.
One of the things that seem to concern them most (Nene Park Academy Students, previous interview), and given that they are GCSE and A' Level students is not entirely surprising, it is a question of whether they're useful for the sake of academic achievement and whether they undermine academic achievement.
And that's the kind of debate that you get, not just in relation to cognitive enhancers, but you also get this in relation to the use of enhancers in sporting performance.
Using the athletics analogy for a moment - if I were to take all the performance enhancing drugs in the world, that still would not make me champion sprinter if I never got off the sofa, and the same kind of thing could be said in respect of cognitive enhancers. If I take all the cognitive enhancing drugs in the world then that will make the blind bit of difference unless I spent some time sitting in front of a book. All an enhancer will do is sharpen your performance.
Hannah - I mean, it's a really important point to note, so these cognitive enhancers, these smarter drugs, it's not the case that you take them and they suddenly just make you smart. They don't just download information into your brain like a memory stick. You still have to put the effort in, you still have to do the work. They just make that work, possibly at that learning phase, more efficient, and also help you to pay attention so that you can absorb information as you're learning.
Iain - Yes, there are also concerns about whether cognitive enhancers are necessarily what we want. So, if you're talking about specific tasks, learning a list of new vocabulary or even being a surgeon who wants to concentrate on the patient in front of him, is that kind of thing where we might want to say that a drug that can help us concentrate and really focus down and not get distracted by shiny things is exactly what we want.
But there are other times where that might be a very, very bad idea. Suppose as a scientist you are not just going through the kind of everyday lab work, but you're trying to come up with a new solution to a particular problem where you'd like to find a new way to attack a particular form of cancer or something. And it's a tricky problem and people have been working on this for years and they have not quite got it yet. In that sort of situation, it's not always obvious that the drug to make you concentrate more is what you want.
There is some evidence, there's a paper published in 2003, it suggested that there's a correlation between creativity and what we might loosely call 'ease of distraction.' So the thought is here that the kind of person who doesn't filter out information but who doesn't concentrate on what is apparently the most salient thing, but whose mind occasionally wonders.
That kind of person can be correlated to the kind of person who is creative and gets recognised for being creative, for example, publishing novels and that kind of stuff.
Sometimes it's good that your mind be elsewhere. There's another quick point that we could make. It's obviously true that there are certain groups of the population that have problems with their memory and there's a very, very good reason to come up with drugs that would help them with if we're talking about the elderly people who might be isolated socially because their memory is failing.
On the other hand, whether they're (the cognitive enhancers) particularly useful in a day to day level is again, not entirely obvious because what we're very, very good at already is outsourcing memory whether that be in terms of something as simple as keeping a pen and paper to hand on that electronic PDA. So we could just look at those as cognitive enhancers in one sense. In which case, do we need to worry about what's going on inside our head? Maybe what we need to say is, we need to make sure that people have access to libraries, to other people, to that kind of stuff so that they can engage in intellectual processes on a social level. And then if that's true, we don't have to worry about manipulation or tweaking people's brains quite so much.
Hannah - So, you're really saying that we could cognitively enhance people's brains by stimulating people, by making sure that they're surrounded by a rich environment so that they can learn new things and be stimulated all the time.
Iain - Yes. Why worry about people being able to memorise a list of mathematical formulae or how to perform particular mathematical functions or whatever when we could just give them an electronic calculator? That just seems like a much more efficient way of going about things.
The kind of pride, I guess, that people might have about being able to do all types of memories and regurgitations in their head, but there is a problem with that they are liable to make mistakes.
If you just concentrate on improving people's memory. If the things that they've remembered in the first place is mistaken then you need some kind of external source to cohobate anyway because otherwise they just end up going on in circles. And that being the case, why just don't put external stuff anyway? Why worry about people's brains?
Hannah - That was Dr. Iain Brassington, lecturer in Bioethics and Medical Law at Manchester University.
29:54 - What keeps a Researcher up all Night?
What keeps a Researcher up all Night?
with Matthew Rushworth, Oxford University
Matthew - My name is Matthew Rushworth. I work in Oxford University and I'm a Neuroscientist there.
I suppose that one of the things that I think that most intrigues me most about the brain is the phenomenon that we see that's very prevalent in many different experiments.
And that's the fact that the brain seem to change as a function of experience and this, I think, runs counter to the intuition that many non-neuroscientists have about what the brain does.
We tend to think about the brain as a thing that causes behaviour that produces the way in which we act. And if there's something different about our brain then that constrains the way in which we might behave in the future. But for many neuroscientists, actually it's the opposite that's the case.
As we gather different experiences, as we engage in different types of behaviour then we see that there are subtle changes that occur in the brain.
So for example, if you were to practice juggling for a while, we would see parts of the brain that are concerned with visual spatial coordination changing and appearing to increase in size.
Or if you engage in some other chore then parts of the brain that are concerned with the cognitive processes needed to perform that chore would change in size.
Even it seems if you spend more time engaged in social interaction then parts of the brain that are important for mediating that social interaction will begin to change and increase in size, and change the way in which they interact with other brain region.
So, it isn't just the case that the brain drives the way in which we behave, but it's also really much more of a two-way street. It's also the case that behaviour alters the way in which our brains are structured and alters the way in which they function.
Hannah - That was Dr. Matthew Rushworth from Oxford University, presenting his fascination with the fact that the brain is a bit like a muscle and can be exercised, and affected by how we use it, and by what we surround ourselves by and what we do.
So, it's a case that behaviour changes the brain and the brain changes behaviour.