00:00:00
Speaker 1: I was reading an article on the BBC earlier this week about various bits of research that put together, paint a picture of birdwatching improving cognitive ability and slowing cognitive decline.
00:00:14
Speaker 2: Dr.
00:00:14
Speaker 1: Skalk Berger is a neurosurgeon and an avid birder. Hello, Skalk.
00:00:20
Speaker 2: Hi, John, and good afternoon to your PM Drive listeners.
00:00:24
Speaker 1: What would be the reasons, the brain-related reasons, why this would be the case?
00:00:30
Speaker 2: Well, there's three scientific proven mechanisms that sort of underpin how birdwatching slows cognitive decline. The one that you've referred to in that BBC article of 23 October, largely drew on a March 2026 article published in Journal of Neuroscience by a doctor in cognitive neuroscience aptly named Dr. Wing, who studied specific MRI changes in expert birdwatchers compared to novice birdwatchers. Now, it's been known for quite a long time that London taxi drivers have got larger hippocampal areas in their brains and professional musicians have got increased auditory cortices. So what this Dr. Wing did is he did diffusion MRI studies on expert bird watchers. And he found that there's reduced diffusion on these diffusion MRIs, which indicate that there's less space between the brain cells. So this underpins an increased complexity of the brain cells and a larger interconnectivity. And he postulated that the structural changes then underlines a functional improvement of the brain and that this increases your cognitive reserve. Now, it's very important to differentiate between cognitive reserve and brain reserve. Your brain reserve would be largely structural in your brain size and your neuronal count, whereas your cognitive reserve is something that you can modify as a bird watcher. And hopefully by us watching birds, we can increase specific areas regarding attention and recognition in our brain. And if we compare with what the Lancet Commission on Dementia Prevention in their update in 2024, they identified 14 modifiable risk factors that account for 45% of cases of dementia. And these include physical inactivity, social isolation, cognitive inactivity, as well as depression. And I hope that your listeners will agree that birdwatching tends to at least be, if not all four of these factors. The question that you might have is, why does birdwatching have an increased sort of high-value cognitive reserve activity compared to Sudoku or word puzzles and the likes? And the reason for this is that it actually engages nine of your cognitive functional areas simultaneously. So there's obviously visual recognition, you know, as Bertus talks about, gives, you know, your general impression of size and shape, you know, so Bertus can quite often quickly identify birds on a quick visual glimpse. There's also auditory discrimination, there's episodic memory, semantic memory, spatial navigation, executive function, you know, planning or birding trips, you know, language where Bertus quite often know the Afrikaans and English and even binomial Latin names, you know, processing speed and even working memories.
00:03:26
Speaker 1: I'm very proud, Skalk. I'm very proud of the fact that I know the Latin names of a couple of hundred. I know the Latin names of 350 birds. The first one I learned was Leptoptilus cruminophorus, which is the Marabar stork. And then I learned Nectarinia talatala, which is one of the sunbirds. You used the word expert a couple of times.
00:03:47
Speaker 2: Yes.
00:03:47
Speaker 1: So how necessary is it to be an expert to have this cognitive advance?
00:03:53
Speaker 2: Well, the most important thing with creating this cognitive reserve is that obviously the quicker you start, the better. The most important period for cognitive reserve building is probably between 40 and 60 years. And if we compare it with a muscle, any sort of exercise for a muscle is good. Obviously, the more trained you are, the more reserve you build up. So the more experienced bird that you are, the bigger the reserve that you build up and the bigger your reserve, the more sort of resilient, you know, you will be to age sort of related cognitive decline.
00:04:28
Speaker 1: Okay. There are a lot of incredible young birders that I've met Over the years, and I know some birders who are 15 and 16 and who are 400 times better birders than I am, despite the fact that I've seen a multiple of species of birds more than they. And so is it, I mean, you said the optimal time is between 40 and 60, but if you're a bird expert at 20, like Adam Riley of Rock Jumper Tours was, surely that stands you in good stead when you get to 40, 50, 60, 70.
00:05:05
Speaker 2: Absolutely, absolutely. The earlier you start, you know, the better your brain is trained. And that's where that plasticity, you know, if the brain comes in, your neuroplasticity, something that when we trained, you know, it wasn't well described. And your cortexes in your frontal, the parietal and occipital lobes actually increase in thickness. And then also this diffusion that could be measured by MRI decreases, indicating that there's more synapses. So the earlier you start, the better, but the critical period that you should not leave it later is 40 to 60, but that doesn't mean that it's ever too late. There's even well-documented studies like the Italian canary study where they've placed canaries in old age homes and they saw a 50% reduction in their geriatric depression scales. I mean, that is something incredible, you know, that not a lot of antidepressants can claim fame to and that without any side effects. So it's never too late, but obviously the earlier you start, the better.
00:06:05
Speaker 1: Is Skaltberger an expert birder?
00:06:09
Speaker 2: Trying to be, but absolute love for birding. And yeah, it's an absolute fantastic leisurely activity. The other thing that we must also understand is that it's obviously a very social thing. And we know that elderly patients, if they become socially isolated, it's devastating to cognitive decline.
00:06:30
Speaker 1: Okay, I'm looking at my technical producer and he's looking unimpressed. I don't think he's going to be asking me for a loan of my cheap binoculars just yet.
00:06:41
Speaker 2: Well, all he needs to do is he needs to log into BirdLife SA's website and he must click on Go Birding and he must find a local bird group and he must look at all the fantastic work that Mark Anderson, the CEO of BirdLife, is doing for conservation. and he must start birding. Okay.
00:07:00
Speaker 1: Well, he'll have to turn some attention away from LeBron James, and I don't.
00:07:04
Speaker 2: Know whether he's prepared to do that.
00:07:05
Speaker 1: Hope to see you in the field with binoculars in hand soon, Dr. Skulk Berger, a neurosurgeon and avid birder.
Speaker 1: I was reading an article on the BBC earlier this week about various bits of research that put together, paint a picture of birdwatching improving cognitive ability and slowing cognitive decline.
00:00:14
Speaker 2: Dr.
00:00:14
Speaker 1: Skalk Berger is a neurosurgeon and an avid birder. Hello, Skalk.
00:00:20
Speaker 2: Hi, John, and good afternoon to your PM Drive listeners.
00:00:24
Speaker 1: What would be the reasons, the brain-related reasons, why this would be the case?
00:00:30
Speaker 2: Well, there's three scientific proven mechanisms that sort of underpin how birdwatching slows cognitive decline. The one that you've referred to in that BBC article of 23 October, largely drew on a March 2026 article published in Journal of Neuroscience by a doctor in cognitive neuroscience aptly named Dr. Wing, who studied specific MRI changes in expert birdwatchers compared to novice birdwatchers. Now, it's been known for quite a long time that London taxi drivers have got larger hippocampal areas in their brains and professional musicians have got increased auditory cortices. So what this Dr. Wing did is he did diffusion MRI studies on expert bird watchers. And he found that there's reduced diffusion on these diffusion MRIs, which indicate that there's less space between the brain cells. So this underpins an increased complexity of the brain cells and a larger interconnectivity. And he postulated that the structural changes then underlines a functional improvement of the brain and that this increases your cognitive reserve. Now, it's very important to differentiate between cognitive reserve and brain reserve. Your brain reserve would be largely structural in your brain size and your neuronal count, whereas your cognitive reserve is something that you can modify as a bird watcher. And hopefully by us watching birds, we can increase specific areas regarding attention and recognition in our brain. And if we compare with what the Lancet Commission on Dementia Prevention in their update in 2024, they identified 14 modifiable risk factors that account for 45% of cases of dementia. And these include physical inactivity, social isolation, cognitive inactivity, as well as depression. And I hope that your listeners will agree that birdwatching tends to at least be, if not all four of these factors. The question that you might have is, why does birdwatching have an increased sort of high-value cognitive reserve activity compared to Sudoku or word puzzles and the likes? And the reason for this is that it actually engages nine of your cognitive functional areas simultaneously. So there's obviously visual recognition, you know, as Bertus talks about, gives, you know, your general impression of size and shape, you know, so Bertus can quite often quickly identify birds on a quick visual glimpse. There's also auditory discrimination, there's episodic memory, semantic memory, spatial navigation, executive function, you know, planning or birding trips, you know, language where Bertus quite often know the Afrikaans and English and even binomial Latin names, you know, processing speed and even working memories.
00:03:26
Speaker 1: I'm very proud, Skalk. I'm very proud of the fact that I know the Latin names of a couple of hundred. I know the Latin names of 350 birds. The first one I learned was Leptoptilus cruminophorus, which is the Marabar stork. And then I learned Nectarinia talatala, which is one of the sunbirds. You used the word expert a couple of times.
00:03:47
Speaker 2: Yes.
00:03:47
Speaker 1: So how necessary is it to be an expert to have this cognitive advance?
00:03:53
Speaker 2: Well, the most important thing with creating this cognitive reserve is that obviously the quicker you start, the better. The most important period for cognitive reserve building is probably between 40 and 60 years. And if we compare it with a muscle, any sort of exercise for a muscle is good. Obviously, the more trained you are, the more reserve you build up. So the more experienced bird that you are, the bigger the reserve that you build up and the bigger your reserve, the more sort of resilient, you know, you will be to age sort of related cognitive decline.
00:04:28
Speaker 1: Okay. There are a lot of incredible young birders that I've met Over the years, and I know some birders who are 15 and 16 and who are 400 times better birders than I am, despite the fact that I've seen a multiple of species of birds more than they. And so is it, I mean, you said the optimal time is between 40 and 60, but if you're a bird expert at 20, like Adam Riley of Rock Jumper Tours was, surely that stands you in good stead when you get to 40, 50, 60, 70.
00:05:05
Speaker 2: Absolutely, absolutely. The earlier you start, you know, the better your brain is trained. And that's where that plasticity, you know, if the brain comes in, your neuroplasticity, something that when we trained, you know, it wasn't well described. And your cortexes in your frontal, the parietal and occipital lobes actually increase in thickness. And then also this diffusion that could be measured by MRI decreases, indicating that there's more synapses. So the earlier you start, the better, but the critical period that you should not leave it later is 40 to 60, but that doesn't mean that it's ever too late. There's even well-documented studies like the Italian canary study where they've placed canaries in old age homes and they saw a 50% reduction in their geriatric depression scales. I mean, that is something incredible, you know, that not a lot of antidepressants can claim fame to and that without any side effects. So it's never too late, but obviously the earlier you start, the better.
00:06:05
Speaker 1: Is Skaltberger an expert birder?
00:06:09
Speaker 2: Trying to be, but absolute love for birding. And yeah, it's an absolute fantastic leisurely activity. The other thing that we must also understand is that it's obviously a very social thing. And we know that elderly patients, if they become socially isolated, it's devastating to cognitive decline.
00:06:30
Speaker 1: Okay, I'm looking at my technical producer and he's looking unimpressed. I don't think he's going to be asking me for a loan of my cheap binoculars just yet.
00:06:41
Speaker 2: Well, all he needs to do is he needs to log into BirdLife SA's website and he must click on Go Birding and he must find a local bird group and he must look at all the fantastic work that Mark Anderson, the CEO of BirdLife, is doing for conservation. and he must start birding. Okay.
00:07:00
Speaker 1: Well, he'll have to turn some attention away from LeBron James, and I don't.
00:07:04
Speaker 2: Know whether he's prepared to do that.
00:07:05
Speaker 1: Hope to see you in the field with binoculars in hand soon, Dr. Skulk Berger, a neurosurgeon and avid birder.
