an autodidact meets a dilettante…

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adult ADHD – what’s the buzz?

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Jacinta: So this is a commissioned piece, sort of, by someone who wants us to look into this disorder (attention deficit hyperactivity disorder, in full), for our sakes and of course for the sake of humanity.

Canto: Sounds like a first world issue to me.

Jacinta: Okay consider yourself lucky you don’t have to scrounge around rubbish heaps for a living, or travel miles on a half-dead donkey to see a medico, or dodge government bullets because you’re an outspoken female…

Canto: Okay okay. So we know that diagnoses of adult ADHD have risen substantially in recent years, in the WEIRD* world, along with autism spectrum disorder (ASD), bipolar disorder, major depressive disorder, PTSD, chronic fatigue syndrome, and others. A lot of work is being created for clinical psychologists, and the waiting lists are getting longer. 

Jacinta: So we’ve started by watching a couple of videos, one from CNBC in the US, another from the ABC in Australia. And a few points here about research and reliable info. Avoid social media! And for the most part avoid commercial news and info networks, which are privately owned and often have a commercial-financial agenda. The most reliable sources in the WEIRD world are generally government subsidised and mandated sites (the ABC in Australia, the BBC in Britain, PBS and NPR in the USA, DW (Deutsche Welle) in Germany, France TV and Radio France, for example). 

Canto: Well, we’ve broken that rule by starting with this video from CNBC, but it does give a good overview of the symptoms, via field professionals such as Dr Leonard Adler, director of an adult ADHD programme at NYU. The symptoms are divided into two types, those associated with inattentiveness and with hyperactivity, though there are obvious crossovers. Under each type heading, nine more or less connected symptoms are described. For example, symptoms of inattentiveness include ‘forgetfulness in daily activities’, ‘failure to finish tasks’ and ‘losing important things’, and under hyperactivity comes ‘interrupting others’ or ‘trouble with turn-taking’, and ‘being always ‘on the go”. Apparently you need at least five of the nine symptoms in either category to be diagnosed with ADHD, at least in the USA. Personally, I can relate to all of the symptoms some of the time. All of this, by the way, comes from the famous, or infamous, DSM-5, the 5th edition of the diagnostic and statistical manual of mental disorders. 

Jacinta: So you may be skeptical, but on the question posed throughout this video: ‘Is ADHD on the rise or is there simply a rise in diagnoses?’, my answer would be ‘yes there is a rise in diagnoses’, but not for the cynical reason you seem to favour – that it’s all about lining the pockets of psychiatrists. Remember we’ve been studying Freud and the post-Freudians, who pioneered the uncovering of disorders due to childhood trauma, sexual repression, unconscious guilt and the like, all in a groping, hit-and-miss sort of way, before anything much was known of neurology, endocrinology or genetics. Now in the 21st century, we can make connections between genetics, family and personal histories and brain processes in a more scientific way – at least slightly. There’s a long way to go. And this has led us to the reality of ongoing behavioural disorders, where previously people were just considered in vague terms as oddballs, eccentrics, psychos, losers or pains in the arse. 

Canto: Steady on. I understand that it’s not about having some symptoms sometimes, which we all do, it’s about having a number of them to a degree that it becomes debilitating. And, as more than one expert has said, what’s frustrating to these sufferers is that sometimes, with certain specific tasks, or aspects of their professional lives, they perform perfectly well on a regular basis, while the rest of their lives are a mess of procrastination, disorganisation, impulsivity and the like. But the more I learn about the disorder, the more I wonder about treatment. These symptoms seem so multi-faceted, I can’t imagine how they can be dealt with though drugs. I can’t even begin to imagine the brain chemistry behind such varied behaviour. Surely there’s no medication that’s going to make you more organised or a better listener – never mind both at the same time.

Jacinta: Well, and yet it all has to be about brain chemistry and signalling. What else can it be? And patterns of behaviour – that’s to say, patterns of brain signalling, that have become habitual since childhood. In response to family dynamics and such. No free will, remember. Much that I’ve heard so far indicates that it runs in families. And of course there are prescription medications for the disorder. So we have to look at effectiveness (method of action), cost, availability and any side-effects or downsides. And then there are other treatments such as cognitive behavioural therapy. 

Canto: Yeah I’ve heard that medications are expensive, and I doubt that therapy comes cheaply either. But let’s look at the brain of ADHD sufferers and what can be done medically, if anything, to alter it. 

Jacinta: Well Britain’s National Health Service has this to say: 

Research has identified a number of possible differences in the brains of people with ADHD from those without the condition, although the exact significance of these is not clear. For example, studies involving brain scans have suggested that certain areas of the brain may be smaller in people with ADHD, whereas other areas may be larger. Other studies have suggested that people with ADHD may have an imbalance in the level of neurotransmitters in the brain, or that these chemicals may not work properly.

Canto: Wow, that’s really informative. I like the bit about smaller or larger. Are they talking about brains or dicks? I mean, really… 

Jacinta: Hmm. We need to look at research papers. And one thing I note is that researchers don’t readily distinguish ‘Adult ADHD’ because it’s understood to have emerged in childhood, though symptoms might have changed over time. In fact many children may ‘get over it’. Dr Judy Ho, in an interview on ADHD in the USA, quoted that childhood ADHD affects some 5% of the population but the adult version affects some 2.5%, which seems to make sense. 

Canto: Well, having checked Google Scholar, I don’t see much in the way of recent research that jumps out. Sheeting home the various symptoms of the disorder to brain chemistry is really difficult…

Jacinta: Well since they do have medications on the market – the NHS describes 5 types- methylphenidate, lisdexamfetamine, dexamfetamine, atomoxetine and guanfacine – and these presumably work on brain chemistry, they must have some idea. ..

Canto: Well these are generally amfetamines, which act as stimulants, speeding up brain functions through the release of hormones and monoamine neurotransmitters such as dopamine and norepinephrine, and this kind of ‘upper’ activity would help with the disorder most associated with ADHD, which is depression, though there are definite downsides related to prolonged use or overuse. Combining, and possibly replacing, such medications with more behavioural-analytical treatments such as Cognitive Behavioural Therapy might be an idea, if there were enough decent therapists around, and if it was affordable, but it’s all a bit hit and miss. 

Jacinta: You have to distinguish between proximal causes and ultimate causes. The proximal causes of most of these conditions is hormone levels and neurotransmitter activity, but that says nothing about why those levels are higher in some people than in others. If you don’t know the underlying causes, you’re just treating symptoms – drugging people to behave ‘normally’. But those underlying causes are generally fiendishly difficult to deal with – for example how can you cure an abused childhood, or damage done in the womb? 

Canto: But many people with ADHD may just want to be ‘normalised’, to a degree. They know that what’s been done to them can’t be undone, but they just might want those symptoms reduced, to concentrate better, to be more organised, to calm down, whatever. 

Jacinta: And given that we’re not that good at tolerating differences, why not give people drugs so they can all be the same, at least tolerably so….

*western ,educated,industrial,rich,democratic

References

ADD/ADHD – What is Attention Deficit Hyperactivity Disorder? (video)

https://www.nhs.uk/conditions/attention-deficit-hyperactivity-disorder-adhd/treatment/

https://www.cdc.gov/ncbddd/adhd/index.html


Written by stewart henderson

December 19, 2022 at 9:39 pm

A bit about schizophrenia – a very bizarre ailment

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Having, for a book group, read a strange novel written a little over 50 years ago, by Doris Lessing, Briefing for a descent into hell, the title of which may or may not be ironic, and being reasonably interested in the brain, its functions and dysfunctions, I’ve decided to use this post to update my tiny knowledge of schizophrenia, a disorder I’ve had some acquaintance with.

Lessing’s book may or may not be about schizophrenia, because it doesn’t concern itself with labeling any mental disorders, or with the science of brain dysfunction in any way. The focus is upon the imaginative world of an Oxbridge academic, a lecturer in classical mythology or some such, who, having been found wandering about in some Egdon Heath-type landscape, with no identification papers or money, and a lack of proper lucidity, is brought into a psychiatric facility for observation and treatment. The vast bulk of the book is told from this individuals’s perspective. Not that he tells the story of his illness, he simply tells stories – or Lessing tells stories on his behalf. Somehow the reader is allowed to to enter the main character’s inner landscape, which includes a voyage around the Pacific Ocean, another voyage around the solar system (conducted by classical deities) and harrowing, but fake, war-time experiences in the Balkans. Along the way we’re provided with the occasional dazzling piece of insight which I think we’re asked to consider as the upside, or mind-expanding nature, of ‘madness’ – somewhat in the spirit of Huxley’s Doors of Perception and Timothy Leary’s psychedelia. At the end of the book the professor is returned to ‘normality’ via electric shock treatment, and becomes, apparently, as uninteresting a character as most of the others in the book, especially the doctors responsible for his treatment, only known as X and Y. 

So, there are problems here. First, Lessing’s apparent lack of interest in the science of the brain means that we’re at a loss to know what the academic is suffering from. Madness and insanity are not of course, legitimate terms for mental conditions, and Lessing avoids using them, but offers nothing more specific, so we’re reduced to trying to deduce the condition from what we know of the behaviour and ramblings of an entirely fictional character. I’ve come up with only two not very convincing possibilities – schizophrenia and brain tumour. A brain tumour is a useful literary device due to the multifaceted nature of our white and grey matter, which constitutes the most complex organ in the known universe, as many an expert has pointed out. A benign tumour – one that that doesn’t metastasise – may bring on a multiplicity of neurons or connections between them that increase the ability to confabulate – though I’ve never heard of such an outcome and it’s more likely that our ‘imagination’ is the product of multiple regions spread throughout the cortex. Schizophrenia only really occurs to me here because the professor was found wandering ‘lonely as a cloud’, far from home, having had his wallet presumably stolen, so that it took some time to identify him. This reminds me of a friend who has from this condition, and has suffered a similar experience more than once.

One of the symptoms of schizophrenia is called ‘loss of affect’, which means that the sufferer become relatively indifferent to the basics – food, clothing and shelter – so caught up is he in his mental ramblings, which he often voices aloud. It’s rare however, for schizophrenia to make its first appearance in middle-age, as appears to be the case here. Another reason, though, that my thoughts turned to schizophrenia was something I read online, in reference to Briefing for a descent into hell. I haven’t read any reviews of the book, and in fact I had no idea when the book was published, as I’d obtained a cheapie online version, which was undated. So in trying to ascertain the date – 1971, earlier than I’d expected, but in many ways illuminating – I happened to note a brief reference to a review written when the book came out, by the US essayist Joan Didion. She wrote that the book presented an ‘unconvincing description of mental illness’ and that the book displayed the influence of R D Laing. A double bullseye in my opinion. 

I read a bit of R D Laing, the noted ‘anti-psychiatrist’ in the seventies, after which he went decidedly out of fashion. His focus was primarily on schizophrenia – as for example in his 1964 paper ‘Is schizophrenia a disease?’ – though he treated other psychoses in much the same way as ‘a perfectly rational response to an insane world’. This is doubtless an oversimplification of his views, but in any case he seems to have given scant regard to what is actually going on in the brain of schizophrenics. 

Since the sixties and seventies, though, and especially since the nineties and the advent of PET scanning, MEG, fMRI and other technologies, the field of neurology has advanced exponentially, and the mental ailments we suffer from are being pinpointed a little more accurately vis-à-vis brain regions and processes. I’ve noted, though, that there’s still a certain romantic halo around the concept of ‘madness’, which after all human society has been ambivalent about since the beginning. The wise fool, the mad scientist and the like have long had their appeal, and it may even be that in extremis, insanity may be a ‘reasonable’ option. As for schizophrenia, maybe we can live with our ‘demons’, as was apparently the case for John Nash after years of struggle, but it’s surely worth trying to get to the bottom of this often crippling disorder, so that it can be managed or cured without resort to disabling or otherwise unhealthy or inconvenient dependence on medication. 

Schizophrenia is certainly weird, and its causes are essentially unknown. There’s a genetic element – you’re more likely to suffer from it if it runs in the family – but it can also be brought on by stress and/or regular drug use, depending no doubt on the drug. It’s currently described as affecting a whopping one in a hundred people (with enormous regional variation, apparently), but perhaps if we’re able to learn more about the variety of symptoms we might be able to break it down into a group of affiliated disorders. There is no known cure as yet.

One feature of the ‘neurological revolution’ of the last few decades has been the focus on neurotransmission and electrochemical pathways in the brain, and dopamine, a neurotransmitter, was an early target for understanding and treating the disorder (and may others). And that’s still ongoing:

Current research suggests that schizophrenia is a neurodevelopmental disorder with an important dopamine component.

That’s from a very recent popular website, but research is of course growing, and pointing at other markers. A reading of the extensive Wikipedia article on schizophrenia has a near-paralysing effect on any attempt to define or describe it in a blog post like this. Glutamate, the brain’s ‘most abundant excitatory neurotransmitter’, has been a major recent focus, but it’s unlikely that we’ll get to the bottom of schizophrenia by examining brains in isolation from the lived experience of their owners. Genetics, epigenetics, stress, living conditions and associated disorders, inter alia, all appear to play a part. And due to its strangeness, its apparent hallucinatory nature, its modern associations of alienation and dystopia  – think King Crimson’s ’21st century schizoid man’ and much of the oeuvre of Bowie (mostly his best work) – it’s hardly surprising that we feel something of an urge to venerate the schizoid personality, or at least to legitimate it. 

Meanwhile, research will inevitably continue, as will the breaking down of intelligence and consciousness into neurotransmission pathways, hormone production, feedback loops, astrocytes etc etc, and ways of enhancing, re-routing, dampening and off-on switching neural signals via increasingly sophisticated and targeted medications… because a certain level of normality is optimal after all. 

Meanwhile, I’m off to listen to some of that crazy music….

References

https://www.verywellmind.com/the-relationship-between-schizophrenia-and-dopamine-5219904

https://www.verywellmind.com/what-is-dopamine-5185621

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6953551/

https://en.wikipedia.org/wiki/Schizophrenia

Written by stewart henderson

December 1, 2022 at 9:16 pm

more oxytocin fantasies: an interminable conversation 3

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not sure if this measures a significant difference

 

Canto: So, as it turns out, the bonobo-oxytocin connection is all the rage on the internet. I mean, there are at least two articles on it. Here’s a quote from a PubMed article called ‘Divergent effects of oxytocin on eye contact in bonobos and chimpanzees’:

Previous studies have shown that bonobos and chimpanzees, humans’ two closest relatives, demonstrate considerable behavioral differences, including that bonobos look more at others’ eyes than chimpanzees. Oxytocin is known to increase attention to another’s eyes in many mammalian species (e.g. dogs, monkeys, and humans), yet this effect has not been tested in any nonhuman great ape species.

Jacinta: Hmm, so how do they know this? Presumably they’ve dosed subjects with oxytocin and measured their eye contact against controls?

Canto: No no, they know that bonobos have more eye contact than chimps, simply from observation. So they might infer from this that bonobos produce more oxytocin naturally than chimps…

Jacinta: So do women produce more oxytocin than men I wonder? I presume women make more eye contact than men.

Canto: Well in this study they dosed both bonobos and chimps with oxytocin, and the effect – more eye contact – was greater in bonobos than chimps. In fact, chimps even tended to avoid eye contact when shown images of conspecifics.

Jacinta: So, it’s a matter of interplay between this hormone/neurotransmitter and social conditioning?

Canto: Maybe, but you’d think that an increase in this supposedly touchy-feely hormone would act against social conditioning. Isn’t this the point of that drug, ecstacy? That it reduces social inhibitions…  But presumably nothing is ever so simple. Being poor, I only have access to the abstract of this paper, but another abstract, which looks at the effects of oxytocin and vasopressin on chimps, describes them as neuropeptides, just to confuse matters. The abstract also refers to about a dozen brain regions, as well as specific oxytocin and vasopressin receptors, so it gets pretty complicated.

Jacinta: Okay, vasopressin… from Wikipedia:

Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP), or argipressin, is a hormone synthesised from the AVP gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travels down the axon terminating in the posterior pituitary, and is released from vesicles into the circulation in response to extracellular hypertonicity (hyperosmolality). AVP has two major functions… etc etc

Canto: Okay thanks for that, let’s stick with oxytocin for now. It’s produced in the hypothalamus, a smallish region buried deep within the brain, just below the larger thalamus and above the even smaller amygdala. It releases and manages a variety of hormones. Brain signals are sent to the hypothalamus, exciting it to release oxytocin and other hormones, which are secreted into the bloodstream by the posterior pituitary gland….

Jacinta: Can you tell me what oxytocin is actually made of? Its structure? The term ‘hormone’ is just a black box to me.

Canto: Okay, here’s a diagram of oxytocin to try and make sense of:

It’s a polypeptide. A peptide is basically an amino acid chain. FYI:

An amino acid is an organic molecule that is made up of a basic amino group (−NH2), an acidic carboxyl group (−COOH), and an organic R group (or side chain) that is unique to each amino acid. The term amino acid is short for α-amino [alpha-amino] carboxylic acid.

Jacinta: So these are coded for, ultimately, by genes?

Canto: Yes, we’re heading backwards here, but each amino acid is encoded by a sequence of three of the four base pairs in our DNA. Anyway oxytocin, among other things is sometimes given to women while in labour. It helps with the contractions apparently. I’ve also heard that the recreational drug ‘ecstasy’, or MDMA, works essentially by releasing oxytocin.

Jacinta: It just so happens I’ve found an interesting 2014 paper published in Neuropsychopharmacology, my new favourite journal, called ‘Effects of MDMA and Intranasal Oxytocin on Social and Emotional Processing’, and here’s a quote from the abstract:

Oxytocin produced small but significant increases in feelings of sociability and enhanced recognition of sad facial expressions. Additionally, responses to oxytocin were related to responses to MDMA with subjects on two subjective measures of sociability. Thus, MDMA increased euphoria and feelings of sociability, perhaps by reducing sensitivity to subtle signs of negative emotions in others. The present findings provide only limited support for the idea that oxytocin produces the prosocial effects of MDMA.

Canto: That is interesting. If that finding can be replicated, I’d say forget the MDMA, dose people with oxytocin. A small but significant increase in feelings of sociability might just be enough to transform our human world.

Jacinta: Hmmm. Small but significant – that sounds a mite contradictory.

Canto: Not the same as significantly small. That slightly significant dose, administered to Messrs Pudding and Pingpong and their enablers, might’ve saved the lives of many Ukrainians, Uyghurs and advocates of multiculturalism, democracy, feminism and other wild and woolly notions. And it doesn’t really transform characters, it just softens their edges.

Jacinta: Yes it’s a nice fantasy – more productive than butchering the butchers, a fantasy I occasionally indulge in. But not workable really.

Canto: Why not? We dosed petrol with lead, and look at how that worked out. It certainly had an effect. In Japan they still use radium baths (at very low levels) for health purposes, even claiming it as a cure for cancer. I’m not sure if oxytocin baths can ever be a thing, but if so I’m sure there will be early adopters.

Jacinta: Well, it’s good to think positively. Oxytocin is often thought of as a bonding hormone between mother and child. The key would be to ensure it facilitates a more general bonding: to cause Mr Pingpong, for example, to see Uyghur, Tibetan, Yi, Limi, and all the other non-Han ethnicities in China as his sisters – or lovers even, revolting as that would be to those peoples.

Canto: Better than being their oppressors and exterminators.

Jacinta: Slightly. But I wonder, quite seriously, if, assuming such a dose of bonding could be effectuated, we could still function as the sometimes rational, problem-solving, highly creative species we indubitably are. Would there be a price to pay for all that oxytocin? And how would this affect all those other hormones and neurotransmitters and all their myriad effects? Humans are notorious for causing extra problems with their solutions, e.g lead, DDT, etc etc.

Canto: Well, there’s no need to worry about the fallout from this solution as yet. I just googled Putin and oxytocin together and came up empty. Obviously we’re way ahead of the curve.

Jacinta: Haha, it’s not a curve these days, it’s a pivot. Get with the program!

References

https://pubmed.ncbi.nlm.nih.gov/33388536/

https://www.yourhormones.info/hormones/oxytocin/

https://www.acs.org/content/acs/en/molecule-of-the-week/archive/o/oxytocin.html

https://www.britannica.com/science/amino-acid

https://www.wsj.com/articles/BL-JRTB-11551

 

Written by stewart henderson

August 4, 2022 at 10:38 pm

still bitten by the bonobo bug…

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Having written quite a few essays on a future bonoboesque world, I’ve found myself in possession of a whole book on our Pan paniscus relatives for the first time. All that I’ve gleaned about these fellow apes until now has been from the vasty depths of the internet, a gift that will doubtless keep on giving. My benefactor apologised for her gift to me, describing it as a coffee-table book, perhaps more pictorial than informative, but I’ve already learned much that’s new to me from the first few pages. For example, I knew from my basic research that bonobos were first identified as a distinct species in the late 1920s or early 1930s –  I could never get the date straight, perhaps because I’d read conflicting accounts. De Waal presents a more comprehensive and interesting story, which involves, among other things, an ape called Mafuka, the most popular resident, or inmate, of Amsterdam Zoo between 2011 and 2016, later identified as a bonobo. The zoo now features a statue of Mafuka.

More important, though, for me, is that everything I’ve read so far reminds me of the purpose of my bonobo essays, but also makes me wonder if I haven’t focussed enough on one central feature of bonobo society, probably out of timidity. Here’s how De Waal puts it:

It is impossible to understand the social life of this ape without attention to its sex life: the two are inseparable. Whereas in most other species, sexual behaviour is a fairly distinct category, in the bonobo it has become an integral of social relationships, and not just between males and females. Bonobos engage in sex in virtually every partner combination: male-male, male-female, female-female, male-juvenile, female-juvenile, and so on. The frequency of sexual contact is also higher than among most other primates.

In our own society, definitely still male-dominated but also with a legacy of religious sexual conservatism, this kind of all-in, semi-masturbatory sexual contact is absolutely beyond the pale. I’m reminded of the Freudian concept of sublimation I learned about as a teen – the eros or sex drive is channelled into other passionate, creative activities, and, voila, human civilisation! And yet, we’re still obsessed with sex, which we’re expected to transmute into sexual fulfilment with a lifelong partner. Meanwhile, the popularity of porn, or what I prefer to call the sex video industry, as well as the world’s oldest profession, indicates that there’s much that’s not quite right about our sex lives.

This raises questions about monogamy, the nuclear family, and even the human concept of love. This is ancient, but nevertheless dangerous territory, so for now I’ll stick with bonobos. As with chimps, female bonobos often, though not always, move to other groups at sexual maturity, a practice known as philopatry. Interestingly, this practice has similarities to exogamous marriage practices, for example among some Australian Aboriginal groups. It’s interesting, then, that female-female bonds tend to be the strongest among bonobos, considering that there’s no kinship involved.

Needless to say, bonobos don’t live in nuclear families, and child-care is a more flexible arrangement than amongst humans, though the mother is naturally the principal carer. And it seems that bonobo mothers have a subtly closer relationship with their sons than their daughters:

the bond between mother and son is of particular significance in bonobo society where the son will maintain his connection with his mother for life and depend upon her for his social standing within the group. For example, the son of the society’s dominant female, the strong matriarch who maintains social order, will rise in the ranks of the group, presumably to ensure the establishment and perpetuation of unaggressive, non-competitive, cooperative male characteristics, both learnt and genetic, within the group.

Considering this point, it would be interesting to research mother-son relations among human single-parent families in the WEIRD world, a situation that has become more common in recent decades. Could it be that, given other support networks, rather than the disadvantages often associated with one-parent families in human societies, males from such backgrounds are of the type that command more respect than other males? Particularly, I would suspect, from females. Of course, it’s hard to generalise about human upbringing, but we might be able to derive lessons from bonobo methods. Bonobo mothers rarely behave punitively towards their sons, and those sons remain attached to their mothers throughout their lives. The sons of high-status females also attain high status within the male hierarchy.

Yet we are far from being able to emulate bonobo matriarchy, as we’re still a very patriarchal society. Research indicates that many women are still attracted to high-status, philandering men. That’s to say, they’ve been ‘trained’ to climb the success ladder through marriage or co-habitation than through personal achievement. They’ve also been trained into the idea of high-status males as dominating other males as well as females. It is of course changing, though too slowly, and with too many backward moves for the more impatient among us. Two macho thugocracies, Russia and China, are currently threatening the movement towards collaboration and inclusivity that we see in female-led democracies such as Taiwan, New Zealand and a number of Scandinavian countries. It may well be that in the aftermath of the massive destruction wrought by these thugocracies, there will come a reckoning, as occurred after the two ‘world wars’ with the creation of the UN and the growth of the human rights movement and international aid organisations, but it is frustrating to contemplate the suffering endured in the meantime, by those unlucky enough to be born in the wrong place at the wrong time.

Now of course all this might be seen as presenting a romanticised picture of bonobos (not to mention female humans), which De Waal and other experts warn us against. The difference in aggression between bonobos and chimps is more a matter of degree than of type, perhaps, and these differences can vary with habitat and the availability of resources. And yet we know from our studies of human societies that male-dominated societies are more violent. And male domination has nothing to do with simple numbers, it is rather about how a society is structured, and how that structure is reinforced. For example I’ve written recently about how the decidedly male god of the Abrahamic religions, originally written as YWH or Elohim, emerged from a patriarchal, polygamous society in the Sinai region, with its stories of Jacob and Abraham and their many wives, which was reinforced in its structure by origin myths in which woman was created out of a man’s rib and was principally responsible for the banishment from paradise. The WEIRD world is struggling to disentangle itself from these myths and attitudes, and modern science is its best tool for doing so.

One of the most interesting findings, then, from modern neurology, is that while there are no categorical differences between the male and the female brain in humans, there are significant statistical differences – which might make for a difference in human society as a whole. To explain further: no categorical difference means that, if you were a professional neurologist who had been studying the human brain for decades, and were presented with a completely disembodied but still functional human brain to analyse, you wouldn’t be able to assert categorically that this brain belonged to a male or a female. That’s because the differences among female brains, and among male brains, are substantial – a good reason for promoting gender fluidity. However, statistically, there are also substantial differences between male and female brains, with males having more ‘grey’ material (the neurons) and females having more ‘white’ material (the myelinated connections between neurons), and with males having slightly higher brain volume, in accord with general sexual dimorphism. In a 2017 British study involving some 5,000 subjects, researchers found that:

Adjusting for age, on average… women tended to have significantly thicker cortices than men. Thicker cortices have been associated with higher scores on a variety of cognitive and general intelligence tests.

This sounds promising, but it’s doubtful that anything too insightful can be made of it, any more than a study of bonobo neurophysiology would provide us with insights into their culture. But, you never know…

References

Frans De Waal & Frans Lanting, Bonobo: the forgotten ape, 1997.

https://www.humancondition.com/freedom-the-importance-of-nurturing-in-bonobo-society/

https://www.science.org/content/article/study-finds-some-significant-differences-brains-men-and-women

on the origin of the god called God, part 2: the first writings, the curse on women, the jealous god

Written by stewart henderson

June 13, 2022 at 2:43 pm

a bonobo world? 11

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another bitter-sweet reflection on capacities and failures

I was in a half-asleep state, and I don’t know how to describe it neurologically, but subjectively I was hearing or being subjected to a din in my head, a kind of babble, like in an echoing school canteen. Then I heard a knocking sound above the din, then in a transforming whoosh all the din stopped in my head, it became silent apart from the knocking, and then, as a kind of wakening crystallisation clarified things, another sound, of trickling water. I quickly realised this was the sound from the shower above me, and the knocking was of the pipes being affected by the rush of hot water. But what really interested me was what had just happened in my brain. The din, of thought, or inchoate thought, or of confusedly buzzing neural connections, was dampened down instantly when this new sound forced itself into my – consciousness? – at least into a place or a mini-network which commanded attention. It, the din, disappeared as if a door had been slammed on it. 

I can’t describe what happened in my brain better than this, though I’m sure that this concentration of focus, or activity, in one area of my brain, and the concomitant dropping of all other foci or activity, to facilitate that concentration, was something essential to human, and of course other animal, neurology. Something observed but not controlled by ‘me’. Something evolved. I like the way this is shared by mice and men, women and wombats. 

But of course there are big differences too. I’ve described the experience, whatever it is, in such a way that a neurologist, on reading or listening to me, would be able to explain my experience more fully, or, less likely, be inspired to examine it or experiment with its no-doubt miriad causal pathways. I suppose this experience, though more or less everyday and unthreatening, is associated with flight-or-fight. The oddity of the sound, its difference from the background din, or perhaps rather my awareness of its oddity, caused a kind of brain-flip, as all its forces, or most of them, became devoted to identifying it. Which caused me to awaken, to marshall a fuller consciousness. How essential this is, in a world of predators and home intruders, and how much fun it is, and how useful it is, to try for a fuller knowledge of what’s going on. And so we go, adding to our understanding, developing tools for further investigation, finding those tools might just have other uses in expanding other areas of our knowledge, and the world of our ape cousins is left further and further behind. For me, this is a matter of pride, and a worry. I’m torn. The fact that I think the way I do has to do with my reading and my reflections, the habits of a lifetime. Some have nerdiness, if that’s what it is, thrust upon them. I’m fascinated by the human adventure, in its beginnings and its future. Its beginnings are connected to other apes, to old world and new world monkeys, to tarsiers, to tree shrews and rodents and so on, all the way back to archaea and perhaps other forms yet to be discovered. We need to fully recognise this connectivity. Its future, what with our increasing dominance over other species and the earthly landscape, our obsession with growth, our throwaway mindset, but also our ingenious solutions, our capacity for compassion and for global cooperation, that future is and always will be a mystery, just outside of our manipulating grasp, with every new solution creating more problems requiring more solutions. 

A few hundred years ago, indeed right up to the so-called Great War of 1914, human warfare was a much-celebrated way of life. And we still suffer a kind of hero-worship of military adventurism, and tell lies about it. In the USA, many times over the most powerful military nation on earth, the media are always extolling the sacrifice of those who fought to ‘keep America safe’. This is a hackneyed platitude, considering that, notwithstanding the highly anomalous September 11 2001 attack, the country has never had to defend its borders in any war. Military casualties are almost certain to occur in a foreign country, where the USA is seeking to preserve or promote its own interest, generally against the interests of that country. In this respect, the USA, it should be said, is no better or worse than any other powerful country throughout history. The myth of military might entailing moral superiority, which began with the dawn of civilisations, dies hard, as ‘American exceptionalism’ shows. 

But globalism, international trade, travel, communication and co-operation, is making for a safer and less combative human society than ever before. So, as militarism as a way of life recedes, we need to focus on the problems of globalism and economic growth. As many have pointed out, the pursuit of growth and richesse is producing many victims, many ‘left-behind’. It’s dividing families and creating a culture of envy, resentment and often unmitigated hatred of the supposedly threatening ‘other’. The world of the bonobo – that tiny community of a few tens of thousands – tinier than any human nation – a gentle, fun-loving, struggling, sharing world – seems as distant to us as the world of the International Space Station, way out there. And yet…

 

Written by stewart henderson

November 16, 2020 at 12:10 pm

reading matters 9

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New Scientist – the collection: mysteries of the human brain. 2019

  • content hints – history of neurology, Galen, Hippocrates, Descartes, Galvani, Thomas Willis, Emil Du Bois-Reymond, Santiago Ramon y Cajal, connectionism, plasticity, mind-maps, forebrain, midbrain, hindbrain, frontal, parietal and occipital lobes, basal ganglia, thalamus, hypothalamus, amygdala, hippocampus, cerebral cortex, substantia nigra, pons, cerebellum, medulla oblongata, connectome, action potentials, axons and dendritic spines, neurotransmitters, axon terminals, signalling, ion channels and receptors, deep brain stimulation, transcranial direct current stimulation, hyper-connected hubs, 170,000 kilometres of nerve fibres, trains of thought, unbidden thoughts, memory and imagination, the sleeping brain, unconscious activity, the role of dreams, brainwaves during sleep, sleep cycles, traumatic stress disorder, Parkinsons, ADHD, dementia, depression, epilepsy, anaesthesia, attention, working memory, first memories, rationality, consciousness, von Economo neurons, the sense of self…

 

Written by stewart henderson

August 16, 2020 at 3:57 pm

the male and female brain, revisited

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Culture does not make people. People make culture. If it is true that the full humanity of women is not our culture, then we can and must make it our culture.

Chimamanda Ngozi Adichie

An article, ‘Do women and men have different brains?’, from Mysteries of the human brain, in the New Scientist ‘Collection’ series, has persuaded me to return to this issue – or perhaps non-issue. It convincingly argues, to me, that it’s largely a non-issue, and largely due to the problem of framing.

The above-mentioned article doesn’t go much into the neurology that I described in my piece written nearly 7 years ago, but it raises points that I largely neglected. For example, in noting differences in the amygdalae, and between white and grey matter, I failed to significantly emphasise that these were averages. The differences among women in these and other statistics is greater than the differences between women and men. Perhaps more importantly, we need to question, in these studies, who the female and male subjects were. Were they randomly selected, and what does that mean? What lives did they lead? We know more now about the plasticity of the brain, and it’s likely that our neurological activity and wiring has much more to do with our focus, and what we’ve been taught or encouraged to focus on from our earliest years, than our gender. 

And this takes me back to framing. Studies designed to ‘seek out’ differences between male and female brains are in an important sense compromised from the start, as they tend to rule out the differences among men and among women due to a host of other variables. They also lead researchers to make too much of what might be quite minor statistical differences. To quote from the New Scientist article, written by Gina Rippon, author of the somewhat controversial book The gendered brain:

Revisiting the evidence suggests that women and men are more similar than they are different. In 2015, a review of more than 20,000 studies into behavioural differences, comprising data from over 12 million people, found that, overall, the differences between men and women on a wide range of characteristics such as impulsivity, cooperativeness and emotionality were vanishingly small.

What all the research seems more and more to be pointing to is that there’s no such thing as a male or a female brain, and that our brains are much more what we make of them than previously thought. Stereotyping, as the article points out, has led to ‘stereotype threat’ – the fact that we tend to conform to stereotypes if that’s what’s expected of us. And all this fuels my long-standing annoyance at the stereotyped advertising and sales directed at each gender, but especially girls and women, which, as some feminists have pointed out, has paradoxically become more crass and extreme since the advent of second-wave feminism.

And yet – there are ways of looking at ‘natural’ differences between males and females that might be enlightening. That is, are there informative neurological differences between male and female rats? Male and female wolves? Are there any such differences between male and female bonobos, and male and female chimps, that can inform us about why our two closest living relatives are so socially and behaviourally different from each other? These sorts of studies might help to isolate ‘real’, biological differences in the brains of male and female humans, as distinct from differences due to social and cultural stereotyping and reinforcement. Then again, biology is surely not destiny these days. 

Not destiny, but not entirely to be discounted. In the same New Scientist collection there’s another article, ‘The real baby brain’, which looks at a so-called condition known as ‘mummy brain’ or ‘baby brain’, a supposed mild cognitive impairment due to pregnancy. I know of at least one woman who’s sure this is real (I don’t know many people), but up until recently it has been little more than an untested meme. There is, apparently, a slight, temporary shrinkage in the brain of a woman during pregnancy, but this hasn’t been found to correlate with any behavioural changes, and some think it has to do with streamlining. In fact, as one researcher, Craig Kinsley, explained, his skepticism about the claim was raised in watching his partner handling the many new tasks of motherhood with great efficiency while still maintaining a working life. So Kinsley and his team looked at rat behaviour to see what they could find:

In his years of studying the neurobiology underlying social behaviours in rats, his animals had never shown any evidence of baby brain. Quite the opposite, actually. Although rats in the final phase of their pregnancy show a slight dip in spacial ability, after their pups are born they surpass non-mothers at remembering the location of food in complex mazes. Mother rats are also much faster at catching prey. In one study in Kinsley’s lab the non-mothers took nearly 270 seconds on average to hunt down a cricket hidden in an enclosure, whereas the mothers took just over 50 seconds.

It’s true that human mothers don’t have to negotiate physical mazes or find tasty crickets (rat mothers, unlike humans, are solely responsible for raising offspring), but it’s also clear that they, like all mammalian mothers, have to be more alert than usual to any signs and dangers when they have someone very precious and fragile to nurture and attend to. In rats, this shows up in neurological and hormonal changes – lower levels of stress hormones in the blood, and less activity in brain regions such as the amygdalae, which regulate fear and anxiety. Other hormones, such as oestradiol and oxytocin, soar to multiple times more than normal levels, priming rapid responses to sensory stimuli from offspring. Many more connections between neurons are forged in late pregnancy and its immediate aftermath.

Okay, but we’re not rats – nothing like. But how about monkeys? Owl monkeys, like most humans, share the responsibilities of child-rearing, but research has found that mothers are better at finding and gaining access to stores of food than non-mothers. Different behaviours will be reflected in different neural connections.

So, while it’s certainly worth exploring how the female brain functions during an experience unique to females, most of the time women and men engage in the same activities – working, playing, studying, socialising and so forth. Our brain processes will reflect the particular patterns of our lives, often determined at an early age, as the famous Dunedin longitudinal study has shown. Gender, and how gender is treated in the culture in which we’re embedded, is just one of many factors that will affect those processes.

References

New Scientist – The Collection, Mysteries of the human brain, 2019

https://en.wikipedia.org/wiki/Dunedin_Multidisciplinary_Health_and_Development_Study

https://ussromantics.com/2013/10/06/what-do-we-currently-know-about-the-differences-between-male-and-female-brains-in-humans/

Written by stewart henderson

June 25, 2020 at 10:50 pm

interactional reasoning: modularity

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all explained

Mercier and Sperber write a lot about modules and modularity in their book on interactional reasoning and its evolution. I’ve passed this over as I find the concepts difficult and I’m not sure if understanding reasoning as a module, if it fits that description, is essential to the thesis about interactional reasoning and its superiority to the intellectualist model. However, as an autodidact who hates admitting intellectual defeat, I want to use this blog to fully understand stuff for its own sake – and I generally find the reward is worth the pain.

Modules and modularity are introduced in chapter 4 of The enigma of reason. The idea is that there’s a kind of inferential mechanism that we share with other species – something noted, more or less, by David Hume centuries ago. A sort of learning instinct, as argued by bird expert Peter Marler, but taken further in our species, as suggested by Stephen Pinker in The language instinct, and by other cognitive psychologists. 

This requires us to think more carefully about the term ‘instinct’. Marler saw it as ‘an evolved disposition to acquire a given type of knowledge’, such as songs for birds and language for humans. We’ve found that we have evolved predispositions to recognise faces, for example, and that there’s a small area in the inferior temporal lobes called the fusiform face area that plays a vital role in face recognition. 

However reasoning is surely more conceptual than perceptual. Interestingly, though, in learning how to do things ‘the right way’, that’s to say, normative behaviour, children often rely on perceptual cues from adults. When shown the ‘right way’ to do something by a person they trust, in a teacherly sort of way (this is called ostensive demonstration), an infant will tend to do it that way all the time, even though there may be many other perfectly acceptable ways to perform that act. They then try to get others to conform to this ostensively demonstrated mode of action. This suggests, perhaps, an evolved disposition for norm identification and acquisition. 

Face recognition, norm acquisition and other even more complex activities, such as reading, are gradually being hooked up to specific areas of the brain by researchers. They’re described as being on an instinct-expertise continuum, and according to Mercier and Sperber:

[they] are what in biology might typically be called modules: they are autonomous mechanisms with a history, a function, and procedures appropriate to this function. They should be viewed as components of larger systems to which they each make a distinct contribution. Conversely, the capacities of a modular system cannot be well explained without identifying its modular components and the way they work together.

A close reading of this passage should suggest to us that reasoning is one of those larger systems informed by many other mechanisms. The mind, according to the authors, is an articulated system of modules. The neuron is a module, as is the brain. The authors suggest that this is, at the very least, the most useful working hypothesis. Cognitive modules, in particular, need not be innate, but can harness biologically evolved modules for other purposes.

I’m not sure how much that clarifies, though it has helped me, for what it’s worth. And that’s all I’ll be posting on interactional reasoning, for now

Written by stewart henderson

February 6, 2020 at 5:29 pm

discussing mental health and illness

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Canto: I’ve been told I’m on the autism spectrum, by someone who’s not on it, presumably, but who’s also not an expert on such things, but I’m not sure who is.

Jacinta: Well of course we’re all on the autism spectrum, it depends on your location on it, I suppose, if you need to worry. ‘You’re sick’ is one of the oldest lines of abuse, but I’m reminded of a passage in The moral landscape, which I’m currently rereading. He describes a funny-but-not-so-funny piece of research by one D L Rosenhan:

… in which he and seven confederates had themselves committed to psychiatric hospitals in five different states in an effort to determine whether mental health professionals could detect the presence of the sane among the mentally ill. In order to get committed, each researcher complained of hearing a voice repeating the words ’empty’, ‘hollow and ‘thud’. Beyond that, each behaved perfectly normally. Upon winning admission to the psychiatric ward, the pseudo-patients stopped complaining of their symptoms and immediately sought to convince the doctors, nurses and staff that they felt fine and were fit to be released. This proved surprisingly difficult. While these genuinely sane patients wanted to leave the hospital, repeatedly declared that they experienced no symptoms, and became ‘paragons of cooperation’, their average length of hospitalisation was 19 days (ranging from 7 to 52 days), during which they were bombarded with an astounding range of powerful drugs (which they discreetly deposited in the toilet. None were pronounced healthy. Each was ultimately discharged with a diagnosis of schizophrenia ‘in remission’ (with the exception of one who received a diagnosis of bipolar disorder). Interestingly, while the doctors, nurses and staff were apparently blind to the presence of normal people on the ward, actual mental patients frequently remarked on the obvious sanity of the researchers, saying things like ‘You’re not crazy – you’re a journalist’.

S. Harris, The moral landscape, p142

Canto: Well, that’s a fascinating story, but let’s get skeptical. Has that study been replicated? We know how rarely that happens. And there are quite a few other questions worth asking. Wouldn’t most of the staff etc have been primed to assume these patients had a genuine mental illness? And surely only a small percentage would have had the authority to make a decision either way. Who exactly had them committed, what was the process, and what was the relationship between those doing the diagnosis and those engaging in treatment and daily care? Was there any fudging on the part of the pseudo-patients (who were apparently also the researchers) in order to prove their point (which presumably was that mental illness can be easily shammed)? And wouldn’t you expect other patients, many of whom wouldn’t believe in their own mental problems, to be supportive of the sanity of those around them?

Jacinta: Okay, those are some valid points, but are you prepared to accept that a lot of these mental conditions, such as bipolar disorder, borderline personality disorder (the name speaks volumes), attention deficit disorder, narcissistic whatever disorder and so on, are a little flakey around the edges?

Canto: Maybe, but with solid centres I’m sure. Depression is probably the most common of those mental conditions, and too much skepticism on that count could obviously lead to disaster. Take the case of South Korea, which has one of the highest suicide rates in the world. There appears to be a nationwide skepticism about mental health issues there, which clashes with high stress levels to create a crisis of care. Professional help is rarely sought and isn’t widely available. It raises the question of the value of skepticism in some areas.

Jacinta: I wonder if the rapid advances in neurophysiology can help us here. Mental health is all about the brain. In the above quote, the pseudo-patients were mostly diagnosed with schizophrenia. That’s surprising. In my naïveté I would’ve thought there was a neurological test for schizophrenia by now.

Canto: Well, the experiment described in The moral landscape dates from the early seventies, but currently there’s still no diagnostic test for schizophrenia based on the brain itself, it’s all about such symptoms as specific delusions and hallucinations, which could still be shammed I suppose, if anyone wanted to. But what about borderline personality disorder – I was told recently that it’s very real, in spite of the name.

Jacinta: Well, there appears to be a mystery about the causes, and a general confusion about the symptoms, which seem to be rather wide-ranging – though I suppose if a patient displays several of them you can safely conclude that she’s stark staring bonkers.

Canto: Yes that’s a thing about mental illness, quite seriously. You don’t need to be an expert to notice when people are behaving in a way that’s detrimental to themselves and others, especially if it’s a sharp deviation from previous behaviour. And if it’s a slow descent, as quite often depression can be, it’s harder to pick from that person’s standard lugubrious personality, so to speak. And in the end, maybe the labelling isn’t so important as the help and the treatment. But then, people love a label – they want to know precisely what’s wrong with them.

Jacinta: I suppose the difficulty with mental illness and labelling, as opposed to labelling other more ‘physical’ illnesses or injuries, is the near-ineffable complexity of the brain. For example, I notice that among the symptoms of borderline personality disorder are apparent behaviours that don’t really cohere in any way. This site places the symptom of uncertainty and indecisiveness along with extreme risk-taking and impulsiveness, and then there is fear of abandonment, and other odd behaviours which seem to head in different directions, seeming to have one thing alone in common – being extreme or abnormal.

Canto: Yes, again, behaviour that tends to harm the self or others.

Jacinta: At the moment, I think there are still too few connections between neurology and psychiatry and the treatment of mental illness, though it’s a matter of enormous complexity. I had thought, for example, that the role of the neurotransmitter dopamine was essential to our understanding of schizophrenia, but more recent research has found that the neurochemistry of the condition involves many other factors, including glutamate, GABA, acetylcholine and serotonin. There’s so much more work to be done. But we also need to be very aware of the social and cultural conditions that tip people over the edge into mental illness. Changes in the way our brain is functioning might be seen as proximal causes of an increase in depression and suicide, but it’s more likely that the ultimate causes have to do with the stresses that particular organisations, societies and cultures impose upon us.

Written by stewart henderson

June 30, 2019 at 12:45 pm

why do our pupils dilate when we’re thinking hard?

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Canto: So we’re reading Daniel Kahneman’s Thinking fast and slow, among other things, at the moment, and every page has stuff worth writing about and exploring further, it’s impossible to keep up.

Jacinta: Yes with this stuff it’s a case of reading slow and slower. Or writing about it faster and faster, unlikely in our case. A lot of it might be common knowledge, but not to us, though in these first fifty pages or so he’s getting into embodied cognition, which we’ve written about, but there’s new data here that I didn’t know about but which makes a lot of sense to me.

Canto: That’s because you’ve been primed to accept this stuff haha. But I want to focus here more narrowly on experiments Kahneman did early in his career with Jackson Beatty, who went on to become the leading figure in the study of ‘cognitive pupillometry’.

Jacinta: Presumably measuring pupils, which is easy enough, while measuring cognition or cognitive processes, no doubt a deal harder.

Canto: Kahneman tells the story of an article he read in Scientific American – a mag I regularly read in the eighties, so I felt all nostalgic reading this.

Jacinta: Why’d you stop reading it?

Canto: I don’t know – I had a hiatus, then I started reading New Scientist and Cosmos. I should get back to Scientific American. All three. Anyway, the article was by Eckhard Hess, whose wife noticed that his pupils dilated when he looked at lovely nature pictures. He started looking into the matter, and found that people are judged to be more attractive when their pupils are wider and that belladonna, which is used in cosmetics, also dilates the pupils. More importantly for Kahneman, he noted ‘the pupils are sensitive indicators of mental effort’. Kahneman was looking for a research project at the time, so he recruited Beatty to help him with some experiments.

Jacinta: And the result was that our pupils dilate very reliably, and quite significantly, when we’re faced with tough problem-solving tasks, like multiplying double-digit numbers – and they constrict again on completion, so reliably that the monitoring researcher can surprise the subject by saying ‘so you’ve got the answer now?’

Canto: Yes, the subjects were arranged so the researchers could view their eyes magnified on a screen. And of course this kind of research is easy enough to replicate, and has been. My question, though, is why does the pupil dilate in response to such an internal process as concentration? We think of pupils widening to let more light in at times of dim light, that makes intuitive sense, but – in order to seek a kind of metaphorical enlightenment? That’s fascinating.

Jacinta: Well I think you’re hitting on something there. Think of attention rather than concentration. I suspect that our pupils widen when we attend to something important or interesting. As Eckhard Hess’s wife noticed when he was looking at a beautiful scene. In the case of a mathematical or logical problem we’re attending to something intently as well, and the fact that it’s internal rather than external is not so essential. We’re looking at the problem, seeing the problem as we try to solve it.

Canto: Yes but again that’s a kind of metaphorical seeing, whereas your pupils don’t dilate metaphorically.

Jacinta: Yes but it’s likely that our pupils dilate in the dark only when we’re trying to see in the dark. Making that effort. When we turn off the light at night in our bedroom before going to sleep, it’s likely that our pupils don’t dilate, because we’re not trying to see the familiar objects around us, we just want to fall asleep. So even if we leave our eyes open for a brief period, they’re not actually trying to look at anything. It’s like when you enter a classroom and see a maths problem on the board. Your eyes won’t dilate just on noticing the problem, but only when you try to solve it.

Canto: I presume there’s been research on this – like with everything we ever think of. What I’ve found is that the ‘pupillary light reflex’ is described as part of the autonomous nervous system – an involuntary system, largely, which responds ‘autonomously’, unconsciously, to the amount of light it receives. But as you say, there are probably other over-riding features, coming from the brain rather than outside. However, a pupil ‘at rest’, in a darkened room, is usually much dilated. So dilation is by no means always to do with attention or focus.

Jacinta: Well there’s a distinction made in neurology between bottom-up and top-down processing, which you’ve just alluded to, in the sense that information coming from outside, and sensed on the skin, the eye and other sensory organs, is sent ‘up’ to the brain – the Higher Authority, – which then sends down responses, in this case to dilate or contract the pupil, all that is called bottom-up processing. But researchers have found that the pupil isn’t just regulated in a bottom-up way.

Canto: And that’s where cognitive pupillometry comes in.

Jacinta: And here are some interesting research findings regarding top-down influences on pupil size. When subjects were primed with pictures relating to the sun, even if they were’nt bright, their pupils contracted more than with pictures of the moon, even if those pictures were actually brighter than the sun pictures. And even words connected to brightness made their pupils contract. There’s also been solid research to back up the speculations of Eckhard Hess, that emotional scenes, images and memories, whether positive or negative, have a dilating effect on our pupils. For example, hearing the cute sound of a baby laughing, and the disturbing sound of a baby screaming, widens our pupils, while more neutral sounds of road traffic or workplace hubub have very little effect.

Canto: Because there’s nothing, or maybe too much info, to focus our attention, surely? While the foregrounded baby’s noises stimulate our sense of wonder, of ‘what’s happening?’ We’re moved to attend to it. Actually this reminds me of something apparently unrelated but maybe not. That’s the well-known problem that we’re moved to give to a charity when one suffering child is presented in an advertisement, and less and less as we’re faced with a greater and greater number of starving children. These numbers become like distant traffic, they disperse our attention and interest.

Jacinta: Yes well that’s a whole other story, but this brings us to the most interesting of findings re top-down effects on our pupils, and the question we’ve asked in the title. A more scientific name for thinking hard is increased cognitive load, and countless experiments have shown that increasing cognitive load, for example by solving tough maths problems, or committing stacks of info to memory, correlates with increased pupillary dilation. This hard thinking is done in the prefrontal cortex, but we won’t go into detail here about its more or less contested compartments. What I will say is there’s an obvious difference between thinking and memorising, and both of these activities increase cognitive load, and pupillary dilation. Some very interesting studies relating memorising and pupillary dilation have shown that children under a certain age, unsurprisingly, are less able to hold info in short-term memory than adults. The research task was to memorise a long sequence of numbers. Monitoring of pupil response showed that the children’s pupils would constrict from their dilated state after six numbers, unlike those of adults.

Canto: So, while we may not have a definitive answer to our title question – the why question – it seems to be that cognitive load, like any load that we carry, requires the expenditure of energy, which can be manifested in the tightening of muscles in the eye which dilates the pupils. This dilation reveals, apparently, that we’re attending to something or concentrating on something. I can see some real-world applications. Imagine, as a teacher, having a physics class, say. You could get your students to wear special glasses that monitor the dilation and constriction of their pupils – I’m sure such devices could be rigged up, and connected to a special console at the teacher’s desk, so he could see who in the class was paying close attention and who was off in dreamland…

Jacinta: Yeah right haha – even if that was physically possible, there are just a few privacy issues there, and how would you know if the pupillary dilation was due to the fascinating complexities of electromagnetism or the delightful profile of your student’s object of fantasy a couple of seats away? Or how could you know if their apparent concentration had anything much to do with comprehension? Or how would you know if their apparent lack of concentration was to do with disinterest or incomprehension or the fact they were way ahead of you in comprehension?

Canto: Details details. Small steps. One way of finding out all that is by asking them. At least such monitoring would give you some clues to go by. I look forward to this brave new transhumanising world….

References

Daniel Kahneman, Thinking fast and slow, 2012

https://kids.frontiersin.org/article/10.3389/frym.2019.00003

Torres A and Hout M (2019) Pupils: A Window Into the Mind. Front. Young Minds. 7:3. doi: 10.3389/frym.2019.00003

Written by stewart henderson

June 24, 2019 at 11:18 am