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embodied cognition: common sense or something startling? part one – seeing red

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color-effects-on-people-8-638

Canto: So I’ve just read a book that details experiments highlighting the effects of, for example, colour, odour, physical comfort and ’embodied metaphors’ on mood, decision-making and creative thinking…

Jacinta: Embodied metaphors?

Canto: I’ll explain later, or not. What I want to do here is lay the groundwork for a future PD talk on how these findings can improve our educational settings and teaching.

Jacinta: So you’re saying our environment can be manipulated, perhaps, to bring out better results in students?

Canto: Yes, think about it. Will sitting in a soft chair help you to think more creatively or efficiently than sitting in a hard chair? Will standing or walking around improve your thinking? Don’t forget Harry Stottle and the Peripatetics. And can these effects be measured? What about the temperature of the room? The view from the window? Inside or outside?

Jacinta: Okay, so can you give me some solid research data on anything that can improve, say, test scores?

Canto: For a start, don’t ask females to indicate that they’re female on the test booklet when they’re sitting a mathematics test. Their results will be impaired. The very act of writing that they’re female apparently brings to mind the idea that girls can’t do maths. The same has been found with African-Americans and maths. This phenomenon is well known in the literature, and has been called stereotype threat.

Jacinta: Okay, but is this really an example of what you were talking about? I thought it was all about the effect of colour, temperature, lighting etc?

Canto: I’m talking about embodied cognition, or physical intelligence, and yes that research is an example – by getting someone to write their gender before sitting a test, it makes them more aware of their gender; their embodiment is brought to mind. But I’m going to give some quite striking examples of the influence of the colour red on test results. A team of American and German researchers conducted a number of experiments, the first involving 71 American undergrads. Each subject was tested individually. They were told they’d be given an anagram test, in which they had to unscramble sets of letters into words. These were of medium difficulty. After a practice run, the students were randomly divided into three groups. All students were given the same anagram tests on paper, with one difference – each participant was given a number, but with one group, the number was coloured red, with another the colour was green, with the third the colour was black. The number on the top of the paper was called to the subjects’ attention at the beginning of the test, with the excuse that this was necessary for processing. The difference in the test results was striking – those who saw a red number at the top of each page performed significantly worse than the green and black groups.

Jacinta: They saw red, and fell apart? But why would they do that? Has this study been replicated? Maybe the group with the red numbers were just bad at anagrams?

Canto: Good questions, and of course it’s the sort of study that could easily be replicated, but the results are in line with similar studies. Unfortunately I could only read a brief abstract of the original study as the detail is behind a paywall, but all these studies have been written about by Thalma Lobel in her book Sensation: the new science of physical intelligence, and, according to her, this particular study took into consideration the abilities of the groups and made sure that this wasn’t the cause of the difference. Also, the same researchers did a follow-up test in Germany, with altered experimental conditions. Instead of using anagrams they used analogy tests, such as:

legs relate to walk like:

1 tongue to mouth

2. eyes to blink

3. comb to hair

4. nose to face

Jacinta: Right, so the correct answer is 2, though it’s not the best analogy.

Canto: Well, eyes to see might be too easy. Anyway, 46 subjects were given 5 minutes to come up with 20 correct analogies. The analogies were presented on paper, each with a cover page. The subjects were divided into 3 groups and the only difference between the groups was the colour of the cover page. The first group had red, the second green, the third, white.  This time their exposure to the colours was shorter – only seconds before they were asked to turn the page, and they weren’t exposed to the colour during the test itself, after they’d turned the page. Still the results were much the same as in the first experiment – exposure to the red cover page resulted in poorer scores.

Jacinta: Sooo, red’s a colour to be avoided when doing tests. What about the other colours? Were any of them good for improving test scores?

Canto: No, not in these experiments. And again, Lobel assures us that the study controlled for the variable of differential ability. The researchers conducted other studies on a range of participants – using verbal and non-verbal (e.g. mathematical) tests, and the results were consistent – exposing subjects to the colour red, and making them conscious of that colour, resulted in poorer scores.

Jacinta: And they have no explanation as to why? Presumably it’s some sort of connotative value for red. Red is danger, red is embarrassment…

Canto: Nature red in tooth and claw – but red is also the heart, the rose, the Valentine. Red has all sorts of contradictory connotations.

Jacinta: So isn’t it the way that red is seen in our culture? What about controlling for cultural connotations, however contradictory?

Canto: You mean trying it out in Outer Mongolia, or a remote African village? It’s a good point, but you know red is the colour of blood..

Jacinta: And of my life-producing vagina.

Canto: Yeah but look at the wariness with which women are treated for having one of those. Anyway I’m not sure they’ve done the study in those places, but they’ve varied the settings – labs, classrooms, outdoors – and the age-groups and the test-types, and the results haven’t varied significantly. And they did other tests to measure motivation rather than performance.

Jacinta: So you mean how seeing red influenced people’s motivation? Presumably negatively.

Canto: Yes. The same research team tried out an experiment on 67 students, based on the assumption that, if you’re an anxious or under-confident employee, you’ll knock on the boss’s door more quietly, and with fewer knocks, than if you’re a confident employee. That’s assuming you find the door closed, and you don’t actually know why you’ve been asked to see the boss. Reasonable assumptions?

Jacinta: Okay.

Canto: So here’s the set-up. The 67 students were told they would be taking one of two tests: analogies or vocal. The students were shown a sample question from each of the tests, to convince them of the process, though it was all subterfuge basically. They were given white binders, and asked to read the name of the test on the first page. They found the word analogies printed in black ink on a coloured rectangle. The colour was either red or green. Next they were asked to walk down the corridor to a lab to take the test. The lab door was closed, but it had a sign saying ‘please knock’. It was found that those who saw the test title on a red background consistently knocked less often and less insistently.

Jacinta: So they were de-motivated and made more anxious simply by this sight of red. Again, why?

Canto: Learned associations, presumably. Red with danger, with anger, with disapproval.

Jacinta: But – just seeing it on a binder?

Canto: That’s what the evidence says.

Jacinta: Okay – I’m not sure I’m entirely convinced, but all this is a bit negative. Granted we could avoid exposing students to red just in case it inhibits learning, but what about studies that show what might be done to improve learning? That’s what we should be aiming for, surely?

Canto: Okay, so now we’ve eliminated the negative, I promise to accentuate the positive in the next post.

Jacinta: Good, we really need to latch onto the affirmative, without messing with Ms In-between…

 

I like

I like

Written by stewart henderson

January 5, 2017 at 8:39 pm

this one’s for the birds

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clevercrow1

Canto: If anybody doesn’t appreciate the beauty and complexity and general magnificence of birds they should pee off and never darken this blog again.

Jacinta: Right. Now what brought that on, mate?

Canto: Oh just a general statement of position vis-à-vis other species. Charles Darwin, an old friend of mine, was pretty disdainful of human specialness in his correspondence, but he kept a low profile – on this and everything else – in public. I want to be a bit more overt about these things. And one of the things that really amazes me about birds, apart from their physical beauty, is how much goes on in those teeny noggins of theirs.

Jacinta: Yes, but what really brought this on? I haven’t heard you rhapsodising about birds before.

Canto: You haven’t been inside my vast noggin mate. Actually I’ve been taking photos – or trying to – of the bird life around here; magpies, magpie-larks, crows, rainbow lorikeets, honeyeaters, galahs, corellas, sulphur-crested cockies, as well as the pelicans, black swans, cormorants, moorhens, coots and mallard ducks by the river, not to mention the ubiquitous Australian white ibis and the masked lapwing.

Jacinta: Well I didn’t know you cared. Of course I agree with you on the beauty of these beasties. Better than any tattoo I’ve seen. So you’re becoming a twitcher?

Canto: I wouldn’t go that far, but I’ve been nurturing my fledgling interest with a book on the sensory world of birds, called, appropriately, Bird sense, by a British biologist and bird specialist, Tim Birkhead. It’s divided into sections on the senses of birds – a very diverse set of creatures, it needs to be said. So we have vision, hearing, smell, taste, touch, and that wonderful magnetic sense that so much has been made of recently.

Jacinta: So we can’t generalise about birds, but I know at least some of them have great eyesight, as in ‘eyes like an eagle’.

Canto: Well, as it happens, our own Aussie wedge-tailed eagle has the most acute sense of vision of any creature so far recorded.

Jacinta: Well actually it isn’t ours, it just happens to inhabit the same land-form as us.

Canto: How pedantic, but how true. But Birkhead points out that there are horses for courses. Different birds have vision adapted for particular lifestyles. The wedge-tail’s eyes are perfectly adapted to the clear blue skies and bright light of our hinterland, but think of owl eyes. Notice how they both face forward? They’re mostly nocturnal and so they need good night vision. They’ve done light-detection experiments with tawny owls, which show that on the whole they could detect lower light levels than humans. They also have much larger eyes, compared with other birds. In fact their eyes are much the same size as ours, but with larger pupils, letting in more light. They’ve worked out, I don’t know how, that the image on an owl’s retina is about twice as bright as on the average human’s.

Jacinta: So their light-sensitivity is excellent, but visual acuity – not half so good as the wedge-tailed eagle’s?

wedge-tailed eagle - world's acutest eyes

wedge-tailed eagle – world’s acutest eyes

Canto: Right – natural selection is about adaptation to particular survival strategies within particular environments, and visual acuity isn’t so useful in the dark, when there’s only so much light around, and that’s why barn owls, who have about 100 times the light-sensitivity of pigeons, also happen to have very good hearing – handy for hunting in the dark, as there’s only so much you can see on a moonless night, no matter how sensitive your eyes are. They also learn to become familiar with obstacles by keeping to the same territory throughout their lives.

face of a barn owl - 'one cannot help thinking of a sound-collecting device, quoth researcher Masakazu Konishi

face of a barn owl – ‘one cannot help thinking of a sound-collecting device’, quoth researcher Masakazu Konishi

Jacinta: So they don’t echo-locate, do they?

Canto: No, though researchers now know of a number of species, such as oilbirds, that do. Barn owls, though, have asymmetrical ear-holes, one being higher in the head than the other, which helps them to pinpoint sound. It was once thought that they had infra-red vision, because of their ability to catch mice in apparently total darkness, but subsequent experiments have shown that it’s all about their hearing, in combination with vision.

Jacinta: Well you were talking about those amazing little brains of birds in general, and I must say I’ve heard some tales about their smarts, including how crows use cars to crack nuts for them, which must be true because it was in a David Attenborough program.

Canto: Yes, and they know how to drop their nuts near pedestrian crossings and traffic lights, so they can retrieve their crushed nuts safely. The genus Corvus, including ravens, crows and rooks, has been a fun target for investigation, and there’s plenty of material about their impressive abilities online.

seeing is believing

seeing is believing

Jacinta: So what other tales do you have to tell, and can you shed any light on how all this cleverness comes in such small packages?

Canto: Well Birkhead has been studying guillemots for years. These are seabirds that congregate on cliff faces in the islands around Britain, and throughout northern Europe and Canada. They’re highly monogamous, and get very attached to each other, and thereby hangs another fascinating tale. They migrate south in the winter, and often get separated for lengthy periods, and it’s been noted that when they spot their partner returning, as a speck in the distance, they get highly excited and agitated, and the greeting ceremony when they get together is a joy to behold, apparently – though probably not as spectacular as that of gannets. Here’s the question, though – how the hell can they recognise their partner in the distance? Common guillemots breed in colonies, butt-to-butt, and certainly to us one guillemot looks pretty well identical to another. No creature could possibly have such acute vision, surely?

Jacinta: Is that a rhetorical question?

Canto: No no, but it has no answer, so far. It’s a mystery. It’s unlikely to be sight, or hearing, or smell, so what is it?

Jacinta: What about this magnetic sense? But that’s only about orientation for long flights, isn’t it?

Canto: Yes we might discuss that later, but though it’s obvious that birds are tuned into their own species much more than we are, the means by which they recognise individuals are unknown, though someone’s bound to devise an ingenious experiment that’ll further our knowledge.

Jacinta: Oh right, so something’s bound to turn up? Actually I wonder if the fact that people used to say that all Chinese look the same, which sounds absurd today, might one day be the case with birds – we’ll look back and think, how could we possibly have been so blind as to think all seagulls looked the same?

Canto: Hmmm, I think that would take a lot of evolving. Anyway, birds are not just monogamous (and anyway some species are way more monogamous than others, and they all like to have a bit on the side now and then) but they do, some of them, have distinctly sociable behaviours. Ever heard of allopreening?

Jacinta: No but I’ve heard the saying ‘birds of a feather flock together’ and that’s pretty sociable. Safety in numbers I suppose. But go on, enlighten me.

Canto: Well, allopreening just means mutual preening, and it usually occurs between mates – and I don’t mean in the Australian sense – but it’s also used for more general bonding within larger groups.

Jacinta: Like, checking each other out for fleas and such, like chimps?

Cant: Yeah, though this particular term is usually reserved for birds. Obviously it serves a hygienic purpose, but it also helps calm ruffled feathers when flocks of colonies live beak by jowl. And if you ever get close enough to see this, you’ll notice the preened bird goes all relaxed and has this eyes half-closed, blissed-out look on her face, but we can’t really say that coz it’s anthropomorphising, and who knows if they can experience real pleasure?

Jacinta: Yes, I very much doubt it – they can only experience fake pleasure, surely.

Canto: It’s only anecdotal evidence I suppose, but that ‘look’ of contentment when birds are snuggling together, the drooping air some adopt when they’ve lost a partner, as well as ‘bystander affiliation’, seen in members of the Corvus genus, all of these are highly suggestive of strong emotion.

Jacinta: Fuck it, let’s stop beating about the bush, of course they have emotions, it’s only human vested interest that says no, isn’t it? I mean it’s a lot easier to keep birds in tiny little cages for our convenience, and to burn their beaks off when they get stressed and aggressive with each other, than to admit they have feelings just a bit like our own, right? That might mean going to the awful effort of treating them with dignity.

Canto: Yyesss. Well on that note, we might make like the birds and flock off…

how the flock do they do that?

how the flock do they do that?

Written by stewart henderson

November 13, 2015 at 12:06 pm

distributed consciousness – another nail in the coffin of human specialness

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onlinePoster6.jpg

for more on this, the whole conference is available online

I wrote a piece here called ‘Animals R Us’ a few years ago because I was annoyed at certain contemptuous remarks directed at animals – a rather large set to be contemptuous of – and also because I’ve always disliked the idea of human specialness so beloved of some of our religious co-habitants. I was also thinking of the remarks of Marilyn Robinson on consciousness, which I critiqued even more years ago. Atheists, she argued (wrongly) don’t take enough account of consciousness (with the inference that if they did, they’d be more accepting of a supernatural being, presumably). So I’m happy to briefly revisit the complexities and the consciousness of non-humans here.

The latest research reveals more and more the distributed nature of consciousness, and some of this research is summarised in ‘Triumph of the zombie killers’, chapter 1 of Michael Brooks’s book At the edge of uncertainty: 11 discoveries taking science by surprise. He brings up philosopher David Chalmers’s 20-year-old claim about the ‘hard problem’ of consciousness, that it doesn’t appear to be reducible to material processes. In fact, Chalmers went further, saying ‘No explanation given wholly in physical terms can ever account for the emergence of conscious experience.’ Well, forever is a long long time and I wonder what Chalmers would have to say now (I’ll have to check out his more recent pronouncements). In 1994 he used a zombie analogy, suggesting that you couldn’t know whether we were surrounded by zombies, or ‘pretend’ humans, since the sense of self-awareness essential to consciousness cannot be identified or described by methodological naturalism. It’s been difficult to provide a coherent theory to account for this subjective feeling, and Daniel Dennett took the view a couple of decades ago that consciousness is essentially an illusion, or rather an evolved way of dealing with the world which captures the elements of reality we need to get by, and then some. That’s why we can so often be fooled by our brains. We have perceptual glitches and blind spots. An obvious example is the human eye, which only focuses sharply on a tiny area, using the fovea centralis, a patch of densely packed photoreceptor cells only a millimetre in diameter. The rest of our visual field is seen in much lower resolution, and without colour. But we’re not aware of this because of the eye’s movements, or saccades, which average 3 per second. The time between one sharp focus and the next is ‘blacked-out’ of consciousness, creating an illusion of seamlessly moving vision. The analogy with film is obvious.

This evolved use of sight to be ‘good enough’ helps explain our ‘change blindness’, which has been highlighted by a number of recent experiments, and which has been exploited for decades by professional magicians. It also helps explain why we don’t notice mistakes in editorial continuity in films, which are even overlooked by editors, because they involve ‘irrelevant’ background details. This evolved use of eyesight to help us to make enough sense of the world as we need to, as economically as possible, is something shared by many other creatures, as researchers have declared. Consciousness researchers gathered together at Cambridge in July 2012 and issued a ‘declaration on consciousness’, summarising recent findings on consciousness in non-human animals and in infant humans:

Non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviours… humans are not unique in possessing the neurological substrates that generate consciousness. Non-human animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates

It’s a vitally important point that’s being made here. Even to call consciousness an emergent property is misleading, as it suggests that we’re still hung up on the consciousness label, and on detecting the point at which this phenomenon has ‘emerged’. Previous tests for consciousness are gradually being found wanting, as what they test has little to do with the more expansive understanding of consciousness that our research is contributing to, more and more. What’s more, serious damage to, and indeed the complete loss of, such areas of the human brain as the insular cortex, the anterior cingulate cortex, and the medial prefrontal cortex, all vital to our self-awareness according to previous research, haven’t prevented subjects from articulating clear signs of consciousness and self-reflection. There’s no ‘place’ of consciousness in the human or mammalian brain, and signs of intentionality and individual personality are cropping up in a whole range of species.

Early researchers on chimpanzees and other highly developed animals were often dismissive of claims that they were being cruel, citing ‘anthropomorphism’ as a barrier to scientific progress. We can now see that we don’t have to think of animals as ‘human-like’ to recognise their capacity for suffering and a whole range of other negative and positive experiences and emotions. And we’re only at the beginning of this journey, which, like the journey initiated by Copernicus, Kepler and others, will take us far from the hubristic sense of ourselves as singular and central.

Written by stewart henderson

July 29, 2015 at 10:05 am

something to send you to sleep

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sleep-apnea-machine.jpg

sleep apnoea mask – looks great, feels even worse?

I went to a Science in the Pub talk last night, not knowing what to expect. The three speakers were all researching sleep, and the focus was mainly on insomnia and sleep apnoea. How fortunate, for I’m having a problem with insomnia at the moment. I may well have a problem with apnoea too, but because I sleep alone I can’t monitor it. Sleep apnoea is about blocked airways that reduce the intake of oxygen, causing sleep disturbance. Here’s an extract from the Better Health Channel on the subject:

In most cases, the person suffering from sleep apnoea doesn’t even realise they are waking up. This pattern can repeat itself hundreds of times every night, causing fragmented sleep. This leaves the person feeling unrefreshed in the morning, with excessive daytime sleepiness, poor daytime concentration and work performance, and fatigue. It’s estimated that about five per cent of Australians suffer from this sleep disorder, with around one in four men over the age of 30 years affected.

So it’s much more common among older males, and it correlates with excessive weight and obesity. Some years ago, when I had a sleeping partner, she expressed a concern about what she thought might be my sleep apnoea, but since then I’ve lost a lot of weight, and my overall health – apart from my bronchiectasis – has improved, so I don’t intend to worry needlessly over that, but it was interesting to hear about the CPAP mask and other treatments being offered, including the possibility of surgery to the uvula and tongue. Also that the evidence is mounting about the long-term effects of sleep apnoea, upon the heart particularly, though not surprisingly with obesity, confounding factors are hard to control for. The problem I’m having at the moment, though, is ‘advanced circadian rhythm’ insomnia, which has only been happening over the past few weeks and which I’m hoping will sort itself out. Our roughly 24-hour circadian rhythms, our body clock, when running at its best, gives us at least eight hours sleep, optimally between 11pm and 7am, though there is enormous individual variation, and huge variation in tolerance of sleep deprivation, possibly due to genetic factors. Amongst the many varieties of body clock-related sleep disorder, two were focused on last night; delayed-phase and advanced-phase circadian rhythms. The terms are largely self-explanatory. In the delayed-phase type, you stay up late and find it hard to get up in the morning, a common teenage problem (or habit). In the advanced-phase type, which I’m now experiencing for the first time in my life, you find yourself falling asleep alarmingly early, and then waking up – and being alarmingly wide awake, at 4am or sometimes even earlier.

The Circadian Sleep Disorders Network is a great place to learn about the problems, and possible solutions for having a body clock that’s out of synch with the day-night cycle or with your work or other commitments. These problems can lead to all sorts of stresses, but what I took from last night’s session, though it was never explicitly stated, was that your attitude to wonky sleep patterns might be causing more stress than the patterns themselves. In my case, though it’s irritating, I tell myself I needn’t stress over it as I have to get up around 6am for work anyway, and as long as I’m awake and fully operational until 5pm, or 7pm for cooking and eating dinner, it’s no big problem. I’ve not noticed excessive daytime sleepiness or poor concentration (but maybe I’m not concentrating enough). Though I do hope it will right itself, just because being abnormal feels – abnormal. Then again, I’m abnormal in so many other ways that are far more stressful.

Advanced-phase sleep disorder is apparently much less common than delayed phase, though that might just be that it’s less often reported precisely because it doesn’t disrupt work routines. The main treatment is the use of bright light, though I’ve found myself falling asleep in the bright light of the lounge room, or in my bedroom with a bright reading lamp left on. But there’s more to it than just leaving the light on. Here’s a summary from the Sleep Health Foundation:

Bright light visual stimulation should occur in the evening before you go to bed. The light should be brighter than normal indoor lighting. You can obtain it from specialized light boxes, or portable devices that you can wear, e.g. eye glasses. A few examples can be found by a web search for “bright light therapy”. You may need an hour or two of bright light therapy before bed. Some will benefit from nightly use for a week. Others will need longer, sometimes several weeks, to get maximum benefit. It is best used late in the evening, perhaps turning the bright light device off half an hour before bed.

Something to think about if this keeps up. Another treatment is with melatonin, the ’sleep hormone’:

One option is to take a 2mg slow release melatonin tablet (Circadin™) as close to your new (later) bedtime as possible. A second option is to take a small dose of melatonin (0.5 mg), about half way through your sleep period. This could be at a time when you wake up on your own. To change your hours of sleep, you should gradually delay your bed time (e.g. 20 minutes later each night) until you get it to the time that you want. As you delay your bedtime, you will also be delaying the time of your bright light exposure and melatonin intake.

Obviously, neither of these treatments are simple or guaranteed to be effective. Cognitive behaviour therapy was suggested by the experts, if these approaches were unsuccessful, but I know next to nothing about that. For now I’m not too worried, I just hope the problem goes away without my noticing.

Written by stewart henderson

July 5, 2015 at 10:12 am

a change of focus, and Charlie Darwin’s teenage fantasies

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He's just so moi, though I'm more rough than ruff

He’s just so moi, though I’m more rough than ruff

“bashful, insolent; chaste, lustful; prating, silent; laborious, delicate; ingenious, heavy; melancholic, pleasant; lying, true; knowing, ignorant; liberal, covetous, and prodigal”

Michel de Montaigne, ‘Myself’

Sitting at my computer with the ABC’s ‘Rage’ on in the background, when on came a video by an artist who’s taken the moniker ‘Montaigne’, and how could I not be attracted? Good luck to her. I first stumbled on the original Montaigne decades ago, and like thousands before and since, I was fairly blown away. He’s been an inspiration and a touchstone ever since, and to think I’m now approaching his age at his death. One thing he wrote has always stayed with me, and I’ll misquote in the Montaignian tradition, being more concerned with the idea than the actual words – something like ‘I write not to learn about myself, but to create myself’. This raises the importance of writing, of written language, to an almost ridiculous degree, and I feel it in myself, as I’ve sacrificed much to my writing, such as it is. Certainly relationships, friendships, career – but I was always bad at those. All I have to show for it is a body of work, much of it lost, certainly before the blogosphere came along, the blogosphere that retains everything, for better or worse.

The New Yorker captures the appeal of Montaigne well. He wasn’t an autobiographical writer, in that he didn’t dwell on the details of his own life, but as a skeptic who trusted little beyond his own thoughts, he provided a fascinating insight into a liberal and wide-ranging thinker of an earlier era, and he liberated the minds of those who came later and were inspired by his example, including moi, some 400 years on. So, I’d like to make my writings a bit more Montaignian in future (I’ve been thinking about it for a while).

I’ve been focussing mainly on science heretofore, but there are hundreds of bloggers better qualified to write about science than me. My excuse, now and in the future, is that I’m keen to educate myself, and science will continue to play a major part, as I’m a thorough-going materialist and endlessly interested in our expanding technological achievements and our increasing knowledge. But I want to be a little more random in my focus, to reflect on implications, trends, and my experience of being in this rapidly changing world. We’ll see how it pans out.

what's in that noddle?

what’s in that noddle?

Reading the celebrated biography of Charles Darwin by Adrian Desmond and James Moore, I was intrigued by some remarks in a letter to his cousin and friend, William Darwin Fox, referring to the ‘paradise’ of Fanny and Sarah Owen’s bedrooms. This was 1828, and the 19-year-old Darwin, already an avid and accomplished beetle collector and on his way to becoming a self-made naturalist, was contemplating ‘divinity’ studies at Cambridge, having flunked out of medicine in Edinburgh. Fanny was his girlfriend at the time. These bedrooms were

‘a paradise… about which, like any good Mussulman I am always thinking… (only here) the black-eyed Houris… do not merely exist in Mahomets noddle, but are real substantial flesh and blood.’

It’s not so much the sensual avidity shown by the 19-year-old that intrigues me here, but the religious attitude (and the fascinating reference to Islam). For someone about to embark on a godly career – though with the definite intention of using it to further his passion for naturalism – such a cavalier treatment of religion, albeit the wrong one, as ‘inside the noddle’, is quite revealing. But then Darwin’s immediate family, or the males at least, were all quasi-freethinkers, unlike his Wedgewood cousins. Darwin never took the idea of Holy Orders seriously.

Written by stewart henderson

February 8, 2015 at 10:53 am

What do we currently know about the differences between male and female brains in humans?

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Having had an interesting conversation-cum-dispute recently over the question of male-female differences, and having then listened to a podcast, from Stuff You Should Know, on the neurological differences between the human male and the human female, which contained some claims which astonished me (and for that matter they astonished the show’s presenters), I’ve decided to try and satisfy my own curiosity about this pretty central question. Should be fun.

The above link is to How Stuff Works, which I think is the written version of the Stuff You Should Know podcast, that’s to say with more content and less humour (and less ads), but I do recommend the podcast, because the guys have lots of fun with it while still delivering plenty of useful and thought-provoking info. Anyway, the conversation I was talking about was one of those kitchen table, wine-soaked bullshit sessions in which one of the participants, a woman, was adamant that nurture was pretty well entirely the basis for male-female differences. I naturally felt sympathetic to this view, having spent much of my life trying to blur the distinctions between masculinity and femininity, having generally been turned off by ultra-masculine and ultra-feminine traits and wanting to push for blended behaviour, which obviously suggests we can control these things through nurturing such a blending. However, I had just enough knowledge of what research has revealed about the matter to say, ‘well no, there are distinct neurological differences between males and females’, but I didn’t have enough knowledge to give more than a vague idea of what these differences were. The podcast further whetted my appetite, but writing about it here should pin things down in my mind a bit more, here’s hoping.

I’ve chosen the title of this post reasonably carefully, with apologies for its clunkiness. For the fact is, we still know little enough about our brains. I’ve mentioned humans, but I expect there are gender differences in the brains of all mammals, so I’m particularly interested in that part of the brain that distinguishes us, though not completely, from other mammals, namely the prefrontal cortex.

Here’s an interesting summary, from a blurb on a New Scientist article by Hannah Hoag from 2008;

Research is revealing that male and female brains are built from markedly different genetic blueprints, which create numerous anatomical differences. There are also differences in the circuitry that wires them up and the chemicals that transmit messages between neurons. All this is pointing towards the conclusion that there is not just one kind of human brain, but two. …

Men have bigger brains on average than women, even accounting for sexual dimorphism, but the two sexes are bigger in different areas. A 2001 Harvard study found that some frontal lobe regions involved in problem-solving and decision-making were larger in women, as well as regions of the limbic cortex, responsible for regulating emotions. On the other hand, areas of the parietal cortex and the amygdala were larger in men. These areas regulate social and sexual behaviour.

The really incredible piece of data, though, is that men have about 6.5 times more grey matter (neurons) than women, while women have about ten times more white matter (axons and dendrites, that’s to say connections) than men. These are white because they’re sheathed in myelin, which allows current to flow much faster. On the face of it, I find this really hard, if not impossible, to believe. I mean, that’s one effing huge difference. It comes from a study led by Richard Haier of the University of California, Irvine and colleagues from the University of New Mexico, but this extraordinary fact appears to be of little consequence for male performance in intellectual tasks as compared to female. What appears to have happened is that two different ‘brain types ‘ have evolved alongside and in conjunction with each other to perform much the same tasks. Other research appears to confirm this amazing fact, finding that males and females access different parts of the brain for performing the same tasks. In an experiment where men and women were asked to sound out different words, Gina Kolata reported on this back in early 1995 in the New York Times:

The investigators, who were seeking the basis of reading disorders, asked what areas of the brain were used by normal readers in the first step in the process of sounding out words. To their astonishment, they discovered that men use a minute area in the left side of the brain while women use areas in both sides of the brain.

After lesions to the left hemisphere, men more often develop aphasia (problems with understanding and formulating speech) than women.

While I’m a bit sceptical about the extent of the differences between grey and white matter in terms of gender, it’s clear that these and many other differences exist, but they’re difficult to summarise. We can refer to different regions, such as the amygdala, but there are also differences in hormone activity throughout the brain, and so many other factors, such as ‘the number of dopaminergic cells in the mesencephalon’, to quote one abstract (it apparently means the number of cells containing the neurotransmitter dopamine in the midbrain). But let me dwell a bit on the amygdala, which appears to be central to neurophysiological sex differences.

Actually, there are 2 amygdalae, located within the left and right temporal lobes. They play a vital role in the formation of emotional memories, and their storage in the adjacent hippocampus, and in fear conditioning. They’re seen as part of the limbic system, but their connections with and influences on other regions of the brain are too complex for me to dare to elaborate here.  The amygdalae are larger in human males, and this sex difference appears also in children from age 7. But get this:

In addition to size, other differences between men and women exist with regards to the amygdala. Subjects’ amygdala activation was observed when watching a horror film. The results of the study showed a different lateralization of the amygdala in men and women. Enhanced memory for the film was related to enhanced activity of the left, but not the right, amygdala in women, whereas it was related to enhanced activity of the right, but not the left, amygdala in men.

This right-left difference is significant because the right amygdala connects differently with other brain regions than the left. For example, the left amygdala has more connections with the hypothalamus, which directs stress and other emotional responses, whereas the right amygdala connects more with motor and visual neural regions, which interact more with the external world. Researchers are of course reluctant to speculate beyond the evidence, but as a non-scientist, but as a pure dilettante I don’t give a flock about that – just don’t pay attention to my ravings. It seems to me that most female mammals, who have to tend offspring, would be more connected to the flight than the fight response to danger than the unencumbered males would be??? OMG, is that evolutionary psychology?

It’s interesting but hardly surprising to note that studies have shown this right-left amygdala difference is also correlated to sexual orientation. Presumably – speculating again – it would also relate to those individuals who sense from early on that they’re born into ‘the wrong gender’.

Neuroimaging studies have found that the amygdala develops structurally at different rates in males and females, and this seems to be due to the concentration of sex hormone receptors in the different genders. Where there’s a size difference there appears to be a big difference in number of sex hormones circulating in the area. Again this is difficult to interpret, and it’s early days for this research. One brain structure, the stria terminalis, a bundle of fibres that constitute the major output pathway for the amygdala, has become a focus of controversy in the determination of our sense of gender and sexual orientation. As a dilettante I’m reluctant to comment much on this, but the central subdivision of the bed nucleus of the stria terminalis is on average twice as large in men as in women, and contains twice the number of somatostatin neurons in males. Somatostatin is a peptide hormone which helps regulate the endocrine system, which maintains homeostasis.

What all this means for the detail of sex differences is obviously very far from being worked out, but it seems that the more we examine the brain, the more we find structural and process differences between the male and female brain in humans. And it’s likely that we’ll find similar differences in other mammals.

It’s important to note, though, that these differences, as in other mammals, exist in the same species, in which the genders have evolved to be codependent and to work in tandem towards their survival and success. Just as it would seem silly to say that female kangaroos are smarter/dumber than males, the same should be said of humans. The terms smart/dumb are not very useful here. The two genders, in all mammals, perform complementary roles, but they’re also also both able to survive independently of one another. The amazing thing is that such different brain designs can be so similar in output and achievement. It’s more impressive evidence of the enormous diversity of evolutionary development.

Written by stewart henderson

October 6, 2013 at 9:30 am

stress and resilience: what rats are telling us

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I recently read that when you go to the dentist, an almost archetypal stressful experience, your stress will be massively diminished if the dentist tells you, before picking up the drill and attacking your enamel, exactly what he or she plans to do and why. It’s a finding that can surely be safely extrapolated to many other experiences in life, and, perhaps obscurely, it reminds me of the famous story by Franz Kafka, The Trial. K is arrested one fine morning, and he doesn’t know why and he never finds out despite his best efforts, and then he’s executed (excuse the spoiler). A classic literary exploitation of the horror of stress. It reminds me also of how our co-op was treated by its government regulating body, but more of that in later posts.

Kelly Lambert, a veteran stress researcher and rat-lover, describes our growing understanding of the impact of stress and how it might be avoided and treated as one of the most important developments in modern medical and health science. In The lab rat chronicles Lambert displays a pragmatic and down to earth view of stress and depression, with an emphasis on prevention and action rather than ‘treatment’ and medicalisation, which I heartily endorse, while always recognising that there are complex psychological factors that can weigh against individuals taking charge of their lives.

Lambert’s intriguing rat stories serve multiple purposes, of which altering the common view of rats (as pigeons sans wings) is not the least. She teaches us, I think, that we can and have learned a great deal from experiments with animals, and especially rats, but we need to treat them with respect – and can ultimately learn a lot more from them if we do. Among the things they can teach us about are resilience, endurance, reciprocity, social capital, healthy living and self-reliance, and no kidding. But it’s the subject of stress, and building up a resistance to it, that most concerns me here.

Our stress responses are of course necessary and valuable. They motivate us to save ourselves when under attack, or to perform the unpleasant task we must do as part of our job (the prospect of being sacked concentrates the mind wonderfully). Yet the negative physiological effects of stress are the same, whether you’re facing a charging elephant or an angry supervisor. So how do we maximise the motivating force of the stress response, while minimising the negative impact? How do we make ourselves more resilient?

My account here will be abridged – stress is a very complex subject, and I most certainly won’t be giving a full account of it. The first thing is to be aware of stressful situations, of the type I described at the top of this post.

Interestingly, the term stress as applied to humans, other animals and plants, is of very recent coinage, and it’s actually a misapplication from engineering. According to Lambert, in the 1940s, a famous researcher, Hans Selye, began injecting rats with a hormone extract to observe their responses. He noted a heap of immediate negative reactions including swollen adrenal glands, shrivelled thymus glands and stomach ulcers, and was keen to write them all up, but felt he needed more baseline data, so he tried the same experiment, this time using a saline solution to inject the rats with – a placebo, effectively. What he found was the same heap of negative responses. How could this be? It eventually dawned on him that his rough handling of the rats in order to inject them, as well as chasing the scared rats around the cage and dropping them from a height as they squirmed to get out of his hands – all of this was the cause of the adverse reactions. Selye was so intrigued by this that he ditched the hormone extracts and began running experiments to test the rats’ physiological responses to adverse events, deprivation, novel scenarios and the like. This was such a new direction in research that Selye had to find terminology from another discipline to describe the state of mind of the rats as evidenced by their physiological and hormonal responses. He found what he thought he needed in the literature of engineering, with its twin terms stress and strain, but, being a Hungarian reading in English, he appears to have misunderstood that the term stress was applied in engineering to the causal factors operating on, say, a bridge, while strain was a description of the effects of those factors on the strength and durability of the bridge. In any case, psychology had been gifted a new term, one which has been a major feature of psychology and mental and physical health research ever since.

As the evidence mounted for serious negative effects on subjects exposed to events now deemed ‘stressful’, more consideration was given to variation within the findings, so as to better understand resilience in the face of stress. Work done with rats exposed to novel scenarios has shown that the responses vary on a spectrum from neophilic at one extreme to neophobic at the other. That’s to say, when placed in a new environment, the neophilic rats will be happy to explore it, while the neophobic ones will exhibit avoidance and a degree of inertness. Another way to categorise them is ‘bold’ and ‘shy’, and whereas bold and risk-taking creatures (it’s almost inevitable to think of teenage male humans) can create their own physiological problems, such as broken limbs or death by misadventure, the evidence in rats is that they live longer, on average, than their risk-averse fellows. The research also indicates that having the right temperament, or somehow building it into our natures, is key to coping with the day to day stresses that can accumulate in affecting our health in a host of ways.

So how do we enhance boldness or neophilia – in just the right measure – to cope with the slings and arrows? And why is it that some rats and people are more neophilic than others? Not sure that I can provide clear answers to these questions, but let’s come back to them after looking at the rat studies.

 

First, we’ve all heard of homeostasis, right? It has something to do with maintaining your body temperature and internal environment within certain parameters regardless of what’s going on outside. Fine, but studies of stress and responses have added a new, related term, allostasis, to the physiological lexicon. Allostasis is not so much about stability as about appropriate bodily change in response to external stimuli. For example, if you suddenly consume a heap of chocolate, as I’ve been wont to do, you’ll be hoping that your body’s insulin-producing response is timely and appropriate. Neuroscientist Bruce McEwen, adapting another engineering term, introduced the concept of allostatic load, a reference to the strain on the body when it fails to adequately cope with a stressful experience, whether it be heavy lifting or the deaths of loved ones. Both the general concept of stress and the concept of allostatic load were developed by researchers observing the responses of rats.

 

McEwen injected rats with the stress hormone corticosterone for 3 weeks, and then looked for changes in the hippocampus, an area which contains many glucocorticoid receptors, implicated in stress-related responses. The hippocampus is a region essential for spatial learning and memory; it would stand to reason that stressors and memory need to be associated for effective response. The added corticosterone had the effect of reducing the connections and size of the neurons in the region. How did this downsizing affect memory and learning?

McEwen first tried to replicate this effect on the hippocampal neurons by means of stress. So instead of corticosterone injections, he placed the rats in a ‘Plexiglas restraint tube’ for a couple of hours a day for 3 weeks. The physiological changes were similar to those induced by the hormone injections.

 

Another stress experiment was tried by Lambert to see how quickly the brain could be affected. Rats were housed in cages with adjoining running wheels, and their food schedule was restricted to one hour of feeding a day. The rats responded by becoming more, rather than less, energetic, running frenetically and showing all the signs of stress first noted by Hans Selye – swollen or shrivelled glands and stomach ulcers – and shrinking of neurons in the hippocampus. But the shrinking of neurons in all these experiments was reversible, and Lambert considers that this shrinking is probably an energy-saving manoeuvre of the brain. Brains take up a lot of energy, and may react to increased hormone production by downsizing to prevent overload.

 

Returning to the temperamentally bold and shy rats, I’ve noted that the shy ones have shorter lives – 20% shorter on average. Not surprisingly, the bold rats’ hormones returned to base levels more quickly after stress than their shy kin (and often they were actual kin). Clearly, having a more exploratory nature, within limits, is more adaptive than being exploration-averse. Freezing and worrying over novel scenarios isn’t a healthy option.

 

Lambert and her students became interested in pig studies in which piglets, held on their backs for a brief period, reacted either by struggling to escape or by holding still. The struggling piglets were labelled proactive and the apparently passive ones were labelled reactive, but a second test showed that some of the piglets changed tactics. Lambert’s group tried the experiment with rats. They found that some rats were extremely active, some extremely passive, and some switched tactics from one test to another. The last group was labelled as variable or flexible copers. The question was, had this group learned something between the first and second test which had made them change their behaviour?

 

After the tests, the rats were put through an activity-stress program in which they were given a restricted feeding schedule and then were given a choice between running on a wheel or resting. The proactives and the flexible copers ran more than the reactives. The levels of stress hormone were measured in each group. The proactives had more elevated stress levels than the reactives, but, quite surprisingly, the flexible copers had considerably lower stress levels than both the other groups.

 

In another simple test with the same rats, clips were placed on the rats’ tails to see how long they would persist in trying to remove them. The flexible copers persisted longest, and generally interacted more with novel stimuli.

 

The rats were then tested for how they coped with more chronic and unpredictable stress, of the kind that might be compared with serious economic downturns as experienced in the US recently, not to mention Greece, Ireland and other countries. The rat equivalents were strobe lighting, tilted cages, vinegar in their water, and predator odours. What was found with these and other tests was that the flexible copers’ brains produced higher levels of neuropeptide Y (NPY), a neurochemical associated with resilience (special forces soldiers produce a lot of it). The flexible copers also had the highest levels of corticosterone, which assisted them in maintaining a constant state of readiness to meet changing challenges.

 

So, how to turn rats – and people – into more resilient, flexible copers? Perhaps a bit of training might be required. An experiment was conducted in which the profiled rats were assigned to two groups, a ‘contingent training’ group, in which reward was contingent on effort, and a control ‘noncontingent training’ group, the trust fund rats. It was expected, or hoped, that the passive and more stressfully active rats in the contingent training group would, feeling an enhanced sense of control over their environment, increase their NPY levels and generally behave in more resilient ways. The contingently-trained rats, regardless of their coping profiles, all performed better at trying to get rewards (froot loops!) out from inside a cat toy (the task was impossible, but they were being tested on persistence). So far so good. Next, the rats were asked to perform a swim test, which I won’t describe here, but the results were excellent for the flexible copers, who improved their performances even more (and had higher levels of the hormone DHEA, associated with resilience), but the other two profile groups didn’t improve. A disappointing but not entirely surprising result.

A more interesting result came out of the control group. The flexible copers in that group, after a regime of easy benefits, reduced their willingness to make an effort when confronted with the need to do so to gain rewards in subsequent tests. I’ll quote Lambert here at some length:

Instead of having no effect on the coping responses, the trust fund condition erased the advantage typically shown by the flexible copers. The lack of a predictable contingency formula accompanying the presentation of life’s sweetest rewards reset the behavioural computations underlying the rats’ motivation to work for their rewards. They were now characterised by less flexibility in their responses and a shorter tolerance for work that didn’t immediately produce a reward. Had we systematically spoiled our rats? Once again, animals that were more sensitive to associations between effort and consequences would likely be even more affected by the trust fund noncontingency condition; after the fact, it all made so much sense.

So what can we take from these complex but often striking findings? Of course it goes without saying that we’re not rats, but I also like to think it goes without saying that these findings are highly relevant to humans, and all other mammals. Above all we find that removing us from a state in which we have to strive for rewards tends to make us slothful, intolerant and complacent – ‘spoiled’. A term which now has added resonance. How we build in that resilience in the first place is another question – it might be that very early experiences in which we’ve made positive connections between effort and reward, strongly reinforced from time to time, make for a kind of ‘natural’ resilience which we wrongly consider innate. This has always been my suspicion, that the earliest experiences, even in the womb, can set a strong pattern, which is what we’re talking about when we note that a baby seems to have already a set character, whether timid or ebullient, from birth. That character, when it is ‘resilient’, can be spoiled, so that’s something to watch out for. And as to how a set character which is non-resilient can be transformed into a flexible coper, that’s a tougher problem, as you’d expect.

What I like about Lambert’s approach is that she’s always looking for how we can improve our well-being without resort to medications, ways of positively altering our hormone regulation system through behavioural change, rather than through resort to pills. As she points, the use of anti-depressant medications has sky-rocketed since the mid-nineties, as have diagnoses of depression and related disorders. Something’s definitely wrong here. You’re not likely to increase resilience with pills. The good thing is that more and more researchers are coming to realize this, and looking to behavioural change, from exercise to social interaction to the creation of challenges and rewards, for the answers.

 

 

Written by stewart henderson

June 30, 2013 at 8:21 pm