Elections in an AI age & smokers start with less grey matter

A new study by university researchers in Cambridge, Warwick and Fudan in China has found that levels of grey matter in the brain’s frontal lobe - where we make decisions and decide whether or not to follow rules - is linked to an individual’s likelihood of taking up smoking during adolescence. Professor Trevor Robbins is from Cambridge University’s department of psychology and is the study’s co-author. He’s been telling me all about it…

特雷弗-青少年的大脑在一个塑料and developing stage. It's very vulnerable to nicotine and its effects. And so if you start smoking, then the chances are that you will continue smoking as an adult. So what we did was to rely on this fantastic horizon study with European labs, where we screened 2000 14 year olds. We measured their behaviour and their attitudes, including their smoking behaviour and their attitudes to that. And also we scan their brains, not only at 14, but also follow ups at 19 and 23. And one of the main findings of the paper is that for those adolescents who were smoking at 19, already by age 14 there was a change in their brain.

Chris - And critically, Trevor, you are saying that at 14 they weren't smoking yet?

Trevor - Exactly. They weren't smoking yet, but they came to smoke after 14. But at age 14 they had a loss of grey matter in the frontal lobes, which are those structures just beyond the eyes in the brain. Grey matter being nerve cells. And that occurred before smoking. The degree of loss of the grey matter correlated with how much later they became smoking, as it were.

Chris - What does that bit of the brain do, do we think? And can we square that with why this might be happening?

Trevor - Yes, we can. That's a really key question. So what we did in this study is we gave a number of questionnaires, and one of the questionnaires was actually about rule breaking. Do you have a tendency to break rules to be unconventional and not do the norm and maybe disobey your parents or your teachers or whatever. Those questions correlated with the loss of grey matter in the left frontal lobes. Now, there has been a report in the literature about this in brain damaged patients who have damage to the left frontal lobe, they have a problem with rule breaking. So we found results which agreed with that earlier study and provides us with a behavioural mechanism for understanding why they may be smoking earlier. Because maybe they're just going against what their parents and teachers say.

Chris - Are the changes focused just in that part of the brain or do you see changes elsewhere? Because, of course, different areas of the brain are all talking to each other, they're connected, and so therefore what happens in one place does influence elsewhere as well. So do you see any knock on or secondary changes?

Trevor - That's a very good question. So the first point to make is that the left frontal cortex is quite a large area. There are different bits of it, which probably have different functions, but among those functions, adhering to rules may very well be one of them. It's also true that these parts of the brain are connected to other regions of the brain, which we know are involved in addiction. So a very important connection is to the structure called the stratum, where dopamine has an important role in reward and so-called reinforcement mechanisms, which are a very important part of addiction and how drugs manipulate systems to produce addiction. The fact that nicotine is working on the adolescent developing brain probably is another very important factor.

Chris - It sounds then from what you're saying like there's a sort of one two punch going on where we have a predilection to break rules and therefore render one susceptible behaviourally to trying a tobacco or nicotine laced product in the first place - and that could be cigarettes or vaping, presumably, in this era - and then there's a secondary effect, which is that the nicotine itself then almost reinforces the situation because the brain is vulnerable to and susceptible to the effects of nicotine that then entrenches this.

Trevor - Absolutely Chris. And actually there is a second part of the story, which is interesting, and it's this, that the left frontal lobes may be involved in initiation, but once you've started smoking, it seems that the more you smoke, then the more there's an effect on the right frontal lobes. And the right frontal lobes are involved in the enjoyment aspects of sensation seeking. So they're probably involved in controlling the circuits, which depend on dopamine, which nicotine works on initially to produce the hit. And so the second part of this story is the development of nicotine addiction, the reinforcement of the maintenance of smoking, which may depend on nicotine itself or something to do with smoking having some toxic effect on the right frontal lobes and actually reducing grey matter there as well.

Chris - Understanding these mechanisms is obviously rewarding and fulfilling because it explains a lot. But does it have any application in terms of, we know that smoking is a problem, numbers have been going down, but they've since gone up a bit, especially with vaping again, and we're worried about that. So understanding this now, does this give us any kind of tool with which to try and tackle the problem?

Trevor - You've raised a very important issue. Education has to figure strongly. We have to be able to say that there are some individuals, maybe we can identify them, who we have to counsel very carefully and say, now, look, we are really serious about this. You really are at risk here. And maybe that will have an influence. We all know that that's a problem; telling adolescents what to do doesn't always work.

There’s been a sharp rise in the number of Red Admiral butterflies in the UK. The charity Butterfly Conservation has enlisted the help of the public to count them and they think that there has been a rise of more than 300% on last year. Chris spoke with Zöe Randle, senior surveys officer at Butterfly Conservation...

Zoe - What we've done is we've enlisted the help of the general public. We've run the Big Butterfly Count, it's the largest annual citizen science project on butterflies in the world. And we've had over 125,000 counts submitted by almost 90,000 people. So thanks to everyone that's taken part. They've counted in excess of 247,000 Red admiral butterflies.

Chris - So people just go out in their garden or in their nearby park and they're totting up how many butterflies they see in what, an hour or something? Is that how it works?

佐伊-甚至不是一个小时。任何人都可以参加。It's dead easy. All you need to do is spend 15 minutes in a warm, sunny spot and count the different types of butterfly that you see. There's an identification guide on the Big Butterfly Count website that people can download to help them identify the species that they see. And there's also a mobile phone app as well. You can log your counts there or on the Big Butterfly Count website.

Chris - So two questions we need to explore then is, first, why the Red admirals have shot up so much, and then what's happening to the other species. We'll look at that second. So tell us about the Red admirals first. Why do you think they've gone up so much?

Zoe - Well, the Red Admiral is traditionally thought of as a migrant species. It's a summer visitor to our shores. It normally lives in the Mediterranean and North Africa, and they've evolved a survival strategy which helps them track their food plants. So they will move into areas where their food plant is more abundant to escape the summer droughts that are coming in their native lands. But, more recently, the Red admiral has been found to be breeding in the UK and it can survive our winters. So the long term trend for this butterfly from the UK Butterfly Monitoring Scheme is an increase in abundance of 234% and 15% in distribution. And we believe that climate change is driving the increase in numbers that we've seen in the UK this year.

Chris - Where there are winners, there are inevitably losers. Does this mean that some other species that perhaps rely on a cold snap are not doing quite so well?

Zoe - Yeah, that's absolutely right. Climate change is beneficial for some species and detrimental to others. So for example, in Scotland, we've got the Scotch argus butterfly and, as the name suggests, it's primarily found in Scotland. There are a couple of sites in northern England, but what we're seeing is that the butterfly is trying to escape the heat. And what it does is it shifts its range northwards, so it's moving further northwards in Scotland and retracting from those southern ranges. And it's also going up to higher elevations as well to escape the heat. So once you get to the north coast of Scotland, there's not really anywhere for you to go. And once you get to the top of the mountain, where does the butterfly go? So it's a mixed bag. Also, climate change is beneficial for some species. It does enable them to move northwards. But, to habitat specialist species, for example, the Duke of burgundy, the Pearl-bordered fritillary, they can only move northwards and take advantage of climate change if there's suitable habitat in the new envelope of places that open up to it.

Chris - Are we seeing that there are some endangered species that climate change is turning out to be a silver lining to the cloud? As in, it opens up more space for them, more opportunities, more niches. So their numbers are perhaps being rescued?

Zoe - Well, that's right. The work that we're doing at Butterfly Conservation is targeting landscape scale conservation work to benefit these other species. And we are seeing increases in rare species. But let's look at the overall picture, and that is, unfortunately, 80% of the UK's butterflies are declining in number or where they're found. So it's not all good news for all species.