Developmental paediatrics: 2020

Monday, 25 May 2020

Student compliance

Work in developmental paediatrics, and you're going to work with schools.

I've met and chatted with many gifted and dedicated teachers over the years. Some grownups tell the story of how, growing up, a schoolteacher took a genuine interest in them and their wellbeing, more than anyone else in their lives, and this is what kept them going.

But some aspects of modern schooling can come as a surprise to those outside the sector. Some of it can be pretty shocking. There are many 'systems problems' of course, just like for hospitals both public and private. More on that below.

Something which I'm more attuned to now than in the past, is the wide range of skill level and qualities possessed by individual teachers. This should be expected, it's certainly the case for any collection of doctors, even within small specialties.

An education researcher recently published a paper with some first-hand accounts of just how big a difference a teacher's abilities and approach can make, for the young kids in their class. As background, this was a prospectively designed study, the specific classrooms described below weren't picked out especially to serve a prejudged argument. And these were two adjacent classrooms in the same school. Not only that, but all the kids from both classes come together for maths lessons with one of the two teachers.

These were grade 2 classes; the kids mostly aged 7 or 8yo.

[Field notes, recorded by researcher, Classroom 1]: [Mr Smith] writes a word on the board, but it is quite small and I can't read it from where I'm sitting. Charlie, whose desk is nearest me, just outside the main classroom, yells “How do you spell 'description'?" Another child shouts back “it's on the board". Charlie says, “I know, but I can't read it from here." After a while he moves his desk closer to the board, but [Mr Smith] picks up the desk and moves it back to where it was. Charlie says, “But I can't see the board" to which [Mr Smith] replies “if there's a problem, put your hand up and ask." Charlie puts his hand up and I start my timer. After 3 minutes, he's still waiting. Charlie's now banging on his desk and complaining that his hand has been up for ages. [Mr Smith] comes over to Charlie's desk and puts his hand, absently, on the blank sheet of paper on the boy's desk, but he quickly becomes distracted by another student and wanders off. Charlie howls with frustration and gets up to follow the teacher, who turns around and tells him if he has a question he must sit in his seat and raise his hand. The boy goes back to his seat and puts his hand up. It's still up after 5 minutes when the teacher tells them to pack up.

[Field notes, Classroom 2, maths lesson i.e. both classes combined]: The children from [Mr Smith's] class come in and sit quietly on the rug in [Miss Jones's] class. Hands on heads, they know exactly what to do. Aiden, from [Mr Smith's] class, comes into the room talking and [Miss Jones] says softly, but firmly “Shush." She asks generally, “who can remind me of the rules?" and gently reminds them of her behaviour expectations for the activity: “Play fair, no cheating, is there one person in charge? No." She quickly puts them in groups and says “As soon as that timer goes off, where do I expect you to be? Sit down on the carpet and show me you're ready for your Dojo points." She then sends them into their groups by saying “tip-toe to where you're supposed to be' and they do, except Bailey from [Mr Smith's] class, who she calls back and tells him to tip-toe, which he does. She has a lovely manner, saying “thank you, sir" and “beautiful walking." Charlie, from [Mr Smith's] class, has come to work with [Miss Jones] in a small group. She gently strokes Charlie's back to welcome him. She has tubs full of plastic coins. Charlie goes to touch the coins and she says, “we're not touching yet" and he stops. There is shouting from next door and Charlie says, “Why do they have to be so naughty all the time?"

Later, after seven-year-old Charlie has returned to the chaos of his own classroom, he puts his head down on his desk and says quietly: “I want out of this fucking class."

Readers will be relieved to hear that Charlie received no punishment for his profanity, though apart from these field notes he probably received no response either.

The researcher calls it as she sees it: "Mr Smith's classroom is chaos. His relationship with the students is mutually disrespectful." But she does have her eye on the big picture: "Mr Smith clearly requires more support and guidance on proactive classroom management but, in the apparent absence of such support, he resorts to physically manhandling students, even with two other adults in the room: the researcher and the teacher aide."

The main point which the researcher makes in the paper is that past and recent calls for 'no excuses' discipline in schools is not only misguided, it's incoherent, nonsensical, divorced from real life. I entirely agree. How would a 'no-excuses discipline' policy be enacted in Mr Smith's class? Sounds like he could be equipped with a firearm and a set of thumbscrews, and there'd still be bedlam.

My own point is more straightforward - anyone working in developmental paeds or related disciplines should really get hold of this paper and read it. Observations and interpretations of a kid's behaviours and performance, provided by a teacher, can't always be taken at face value. What those observations might mean will depend a lot on whether the teacher making them is a Ms Jones, or a Mr Smith. That's not always immediately apparent.

And I've previously worried out loud about the practice of basing ADHD 'diagnosis' on little more than a parent and teacher questionnaire, dressed up as a 'standardised assessment instrument'. I'd hope that anyone reading this paper could only hesitate to rely on such flimsy pseudoscience before rushing to define a kid they've just met, or pulling out the script pad.

I always want to talk direct with a kid's teacher or wellbeing officer or assistant principal. Not rely on written observations, reports, letters back and forth. For the same reason I want to take a history in real time in real life, not just rely on a 1 page written summary. This often leads to an amazing amount of phone tag. Can be frustrating but I think the main reason for it is that schools and teachers just aren't accustomed to anyone outside school wanting to take the time to actually talk with them.

*****

Aren't they beautiful giant wheat containers

'The researcher' is Prof Linda Graham. Prof Graham has published excellent papers for the last 15 years, many of them on the important questions of how reliably modern schooling really does deliver education to all children; and on the intersection of education, psychology, and medical practice, and its associated dangers, for many kids in the system.

You'll no doubt hear more from me, on the Prof and her work. I only came across it all a couple of months ago. This amazes me, since I follow the related literature fairly closely. But none of Prof Graham's output has come across my line of sight, for the last 15 years.

No doubt this is largely because Prof Graham's academic home - in terms of university faculties, conferences, and journals - is in Education. Whereas the stuff I read, and people I talk to, are mostly in neuroscience, or dev medicine, or psychology, etc.

This is a problem! I wish all paediatricians and paediatric trainees had the benefit of access to Prof Graham's work. I'm sure that many would find it as informative as I do. But I wonder how many, through lucky chance like mine, have ever read a paper of hers - 5? 50? None??

Same query for clinicians in other disciplines. Some excellent speechies, child psychs, and OTs work closely with a school to support a particular kid. Often they have an ongoing working relationship with a particular school, which must add value exponentially - as would familiarity with Prof Graham's research. I'd guess that a fair few such non-medical dev clinicians are familiar with it. At least one is, the redoubtable Pamela Snow, speech pathologist and scourge of education reactionaries.

*****

I'd better at least mention some of the school system problems I glossed over above. Each worthy of its own post, or journal article, or book. So this is a very brief rundown. Sorry to end on a downer.

Literacy. Put at least an hour aside, perhaps have a stiff drink or Valium handy. Then google 'reading wars'.

Behaviour vs. attention. A widespread belief among schools and teachers is that child behaviours must be addressed first, other progress will follow. For 'ADHD', this belief entails that the first step and priority is to get the kid sitting quietly in their seat, not roaming around the classroom or cracking jokes. Once that's achieved, the kid will naturally concentrate on the teacher's instruction, so the story goes. The reality is of course entirely in the opposite direction - some kids who have their attentional control ability boosted will better engage with classroom activities. But only if the instruction itself is sufficiently engaging.

The Prep year used to be just that, a preparatory year, before school proper. Not anymore. Now a kid's '4 Year Old Kinder', the year before Prep (Victoria, Australia) is treated as the year in which the kid better get their act together. Or for some kids I see, their plain (i.e. 3yo) kinder year is their first encounter with expectations and standards. This push is well intentioned, the rationale being that possible future learning problems can be headed off, early. The problem is that all kids, but especially very young kids under 6yo, naturally learn through spontaneous play and exploration. This is as scientifically well established as the periodic table. But in order to 'start educating' very young kids, a reflexive tactic from our very clunky system has been to try the same approach in kindergarten, as in Years 1+. With the expectation that all very young kids will as readily sit on the mat, listen to the teacher, and not spontaneously wander off or interact with their neighbour, as most 6yos can. I read reports in which sitting-quietly-on-the-mat is talked about as if it was its own standalone developmental ability. This. Is. Nuts.

Much of which are addressed in the Prof's research. Along with plenty else of great importance.

Further reading:

https://drlindagraham.wordpress.com/

http://pamelasnow.blogspot.com/

Papers:

Graham LJ, "Student compliance will not mean ‘all teachers can teach’: a critical analysis of the rationale for ‘no excuses’ discipline" (2018) 22 International Journal of Inclusive Education 1242.
https://www.researchgate.net/profile/Linda_Graham3/publication/322100123_Student_compliance_will_not_mean_'all_teachers_can_teach'_a_critical_analysis_of_the_rationale_for_'no_excuses'_discipline/links/5affe0360f7e9be94bd7ef85/Student-compliance-will-not-mean-all-teachers-can-teach-a-critical-analysis-of-the-rationale-for-no-excuses-discipline.pdf

Graham LJ, "The politics of ADHD" (2006) Australian Association for Research in Education Annual Conference.
https://eprints.qut.edu.au/4806/1/4806.pdf

Graham LJ et al., "A longitudinal analysis of the alignment between children’s early word‐level reading trajectories, teachers’ reported concerns and supports provided" (2020) Reading and Writing, doi 10.1007/s11145-020-10023-7.

Monday, 13 April 2020

Vision, perception

Check these figures out, both have a horizontal line in the middle. Which of the horizontal lines is longest?

Assuming you're human (which isn't reported in blogger.com stats), you'll clearly see that the line in the top figure is slightly longer than the line in the bottom figure.

But wait! What's this?

Tricked you! Except, I didn't trick you - your brain tricked you.

Optical illusions like this are a lot of fun. They can do my head in. But then, thinking about visual perception in general can do my head in.

How does vision work again? Easy, you remember the uni textbooks. Light hits cells in the retina, the retinal cells then send the signal to the primary visual cortex for processing, then....

Wrong! We're now clever enough to know that the processing of the pattern of visual stimuli is something which starts as soon as a photon hits a rod or cone, since the complex but orderly distribution of those cells across the retina has been genetically programmed. And there's more information processing by other cells in the retina, and then more at the first 'relay station', the lateral geniculate nucleus in the thalamus. And then on to more processing in the primary visual cortex, which then packages things up and sends it all on to the other visual cortices, and something out of all this is sent on to the brain's motor control area, and its consciousness/executive area, and whoever else is in the group email.

That sure is a lot of processing.

But actually. We're now clever enough to know that this model, of a signal proceeding along a set path, and being processed at each stop along the way, doesn't quite capture what's really going on. Since many nerve fibres from all over the rest of the brain terminate at each point of the visual pathway. These meddlers and micromanagers themselves influence how the visual signal is processed at each point. Starting at that first relay station, the LGN. And these meddling nerve fibres come in similar numbers to those of the visual pathway itself. So, visual perception is more like mutual, continuous, simultaneous, information processing in all directions, if this model is to be believed.

This really is getting out of hand. Who decided that vision has to be this complicated?

Evolution decided. Or however you prefer to frame that - the need for organisms to survive and procreate decided it. Or, engineering 'design principles' decided it. The selfish gene decided it. Any which way, what matters is that the system works. It works in terms of having produced a tool which helped humans survive and procreate.

It helped achieve that by turning patterns of photon energy quanta into perception. The perception of a straight or curved border, where one object ends and another begins. The perception of movement (the just-perceptible and unexpected movement of a lurking predator). The perception of colour (the pastel hues of edible fruits and veges). Etc.

*****

"What's your point, blog dude?? If I wanted a slice of Neuroscience Lite, I would have, well, opened the current issue of any major medical or psychology journal!"

Fair call. My point is that the cliché that 'Each person sees the world in their own individual way' is true, more fundamentally than metaphorically. And just like that, we've jumped from Hard Neuroscience into subjective experience - ewwww!

No, don't be like that. People fool themselves that early neurodevelopment and its disorders can be understood without worrying about subjective experience. But they can't be.

This is especially relevant in autism. The life stories of some autistic people are amazing for how difficult life was for them and their family, at a very young age, compared to the success and happiness they achieve in adulthood. This sometimes happens 'before your eyes' in paediatric practice, a kid who looks very autistic at 2yo might barely at all, 5 or 10 years later (I mean even without intensive therapies of any sort, in some instances).

This doesn't happen in other situations, like intellectual disability. If a very young kid is found to have an IQ of, say, 50, and if it's an accurate measurement, then one can look 20+ years ahead, and (sadly) predict a lot, at least what sort of work or role in society is very unlikely for them.

The difference for some autistic people is their subjective experience of how their body works, and of what happens around them, and to them. They might have a brain which works very well, with that native intelligence underpinning their success in later life. But that's little help to them at a very young age, if as soon as they walk into a new kindergarten, their conscious mind is assaulted by a cacophony of sights and sounds, including those from unfamiliar people, with each of these percepts experienced as a visceral threat to them.

In that situation, the kid's future-blooming native intelligence isn't much material help.

*****

Random additional points:

Francis Crick was a pretty annoying guy. Crick, as in 'Crick and Watson', as in discovered the structure of the genetic code. Nah I'm being silly, I only mean annoying in envy, as one of those people who seem to achieve more in their life than is temperate or considerate.

Having discovered DNA, he felt that emerging neuroscience sounded like a bit of a lark. He teamed up with a younger neuroscientist who has also made big important contributions, Christof Koch.

In 1995 they published a paper titled "Are we aware of neural activity in the primary visual cortex?" Yes that primary visual cortex I talked about earlier in this post, please pay attention, this will be on the examination!

Are we aware of neural activity in the primary visual cortex? Their short answer was - probably not.

But it's the primary visual cortex! What sort of cortical area does it call itself, if its activity doesn't even reach the conscious mind? Has it no shame??

In a 2016 paper, Koch and his mates addressed this question again. The question is "the subject of ongoing debate". Awesome.

So, that's what 20+ years of neuroscience gets you. Turns out the brain really is pretty complicated.

*****

Hang on. I opened this post by saying that I didn't trick you, your brain tricked you.

But what does that even mean? Does it mean that your brain's sitting there, waiting for its chance to deceive you, to deceive your mind? Like a guide dog leading its blind master into the deluxe pet food store, instead of Aldi?

It means nothing, it's nonsense. The brain isn't something neatly separate to the mind. It can't play, well, mind games, with its own mind. There's no little mini-woman or mini-man sitting somewhere in your cranium, sifting through your brain's discharges and sending a sensible synopsis to your mind.

But trying to avoid describing things this way can be tricky. It's a natural habit to do so, in The Contemporary Sociocultural Context.

These days I try to consciously (irony alert!) restrict my use of the word 'brain' to mean 'unconscious mind' in some situations; and not more loosely than that. I admit, this approach doesn't make sense either - the brain is just as much a part of conscious experience as it is a stable of 'zombie agents'. But it seems a useful shorthand, which people generally understand.

There you go! You thought you'd get through this post without having to trudge through any philosophy of mind.

Tricked you.

Saturday, 22 February 2020

ASD 'levels'

With the DSM-5 in 2013, came ASD 'levels'. I wonder what other clinicians have made of this 'innovation' from the American Psychiatric Association.

'Requiring support', 'requiring substantial support', 'requiring very substantial support'. How do these descriptions fit in to current scientific or clinical understanding of autism? Or of psychology generally, or of child neurodevelopment?

To me they don't seem to fit at all. Autism remains poorly understood. A historical barrier to better understanding has been the assumption that autistic people lack intelligence, empathy, an emotional life, or anything to contribute to society. A more enlightened view has only developed very recently. To me it seems that autistic people who are now happy and successful adults, and can finally tell their story and have it heard - they've played as big a part in the tectonic shift in its conceptualisation, as any celebrated clinician or researcher.

One view on early child development is that it is based around the transmission of a society's culture to a young child, initially by their parents and other close adults. And soon enough by a broader range of sources. The meaning of 'culture' here is very broad, encompassing not only social customs, but knowledge about the physical world, 'folk psychology', and understanding of the emotional life of oneself and others.

A related perspective on the struggles which many autistic children face, is that they are just as intelligent, compassionate, and complex as any other human individual. But that for a number of reasons, they don't naturally, automatically, 'receive' the prevailing culture which those around them would otherwise (largely unconsciously) transmit to them. Modern experience shows that if the environment and interactions of an autistic child can be supported and modified in a way suited to their particular strengths and challenges, they do very well.

But how well this support and modification is done, by an adult in the hot seat, varies enormously in reality. This is partly due to the very powerful force of cultural conformity - some adults might never accept that there are many different but equally good ways to live one's life, outside the way they happened to be born into. An example of this is negative reactions, in our society but not all societies, to young kids who won't make eye contact with newly met adults.

But even well-intending adults may need to take on a lot more knowledge, in order to make things work for an autistic child in their charge.

What this means is that the question of how much support an autistic child 'requires', in reality depends as much on the knowledge, beliefs, and actions of the adults around them, as it does on the individual makeup of the autistic child.

Why would the APA introduce such a conceptually flawed definitional layer, over what is already an increasingly incoherent construct? Why do so many Australian clinicians and professional bodies follow its lead, like the children of Hamelin?

I'll suggest an answer to just the first question. These 'levels' look to me to have been created entirely for the convenience of large funding and service bureaucracies. In the US that's health insurance companies, HMOs, or whatever they're called now. Enormous, quasi-private corporations. How handy that any non-clinical corporate worker can receive a documented 'level' of severity for each autistic child, for whom their job is to ration services. The levels don't have much clinical meaning, but they'll look good on paper.

The question of why so many Australian clinicians and professional bodies have meekly fallen into line is harder for me to fathom.

Perhaps a reader of this blog post might hazard an answer?

Further reading:

Frances AJ, "DSM-5 is guide not bible - ignore its ten worst changes" (2 Dec 2012) Psychology Today. https://www.psychologytoday.com/au/blog/dsm5-in-distress/201212/dsm-5-is-guide-not-bible-ignore-its-ten-worst-changes
Prof Frances is a prominent voice of reason on the DSM, has a big Twitter presence, and is an absolute legend.

Silberman S, "Neurotribes" (2015) Penguin Random House.

Grandin T, "Thinking in Pictures" (1995) Penguin Random House.

Further reading, on 'cultural transmission':

Vygotsky LS, "Thinking and speech (1934). https://www.marxists.org/archive/vygotsky/works/words/Thinking-and-Speech.pdf

Bruner JS, "Child's talk" (1983) WW Norton.

Tomasello M et al., "Cultural learning" (1993) 16 Behavioral and Brain Sciences 495.

Friday, 14 February 2020

Neonatal imitation

I'm telling you, the baby started it!

What are these cheeky babies up to? They're demonstrating neonatal imitation, as newborns can from the moment they're born.

Researchers in 1977 got adults to demonstrate certain facial gestures - tongue protrusion, lip protrusion, or open mouth - for 15 seconds, to newborns. After this, the newborns produced the same facial gesture more often than other facial gestures, see Figure below. The same researchers in a later study found the same effect, in babies less than an hour old. They also showed that newborns imitate an adult poking their tongue to one side (a gesture which is less likely to be made spontaneously, or as a reflex).

There's still some controversy over whether this phenomenon is real. An alternative explanation is that the sight of the adult's face causes general arousal in the newborn, with increased actions of all sorts.

Assuming the phenomenon is real, how do newborns do it? How could a newborn translate their visual perception of an adult poking their tongue out, into their own facial motor action?

This is an example of an explanation proposed within an embodied cognition framework, which is quite different to those proposed within traditional frameworks. The debate partly turns on different ideas about the role which symbolic 'representation' plays in human thought and action.

Representation is central to the classical/computational model of brain function. A computer processes information by manipulating the physical patterns within its central processing unit; those physical patterns are themselves symbols/representations of external objects, actions, or concepts. By this model, neural function works the same - the physical pattern of a group of neurons and their connections (or perhaps even a single neuron) becomes a symbol for an external object, which the brain manipulates. This manipulation is what 'thought' or 'cognition' is.

An example of a cognitive representation is a mental map. If you can imagine life before Google Maps, we used to rely on street directories when driving somewhere new. We'd look at the street map, printed on paper, and try to commit the map to memory. It does seem like some sort of neural pattern must work as a representation of the paper map, in our brains.

But other brain functions which might seem to involve this sort of representation, probably don't at all. Like in the outfielder problem, described in a previous post. It seems unlikely that a fielder catches a ball by mentally simulating the ball's trajectory, within a 3D mental map of the playing field.

Much of the scepticism about neonatal imitation has stemmed from an assumption that, for a newborn to imitate an adult's facial gesture, they'd have to use a mental representation of the gesture. Newborns "can visually observe a stimulus, store an abstract representation of that stimulus, and compare it shortly thereafter to a proprioceptive representation (i.e., their own movements)."

Could a newborn's brain really be capable of a such a computational feat?

My reading of the research is that neonatal imitation is real enough. But it might not involve this sort of representation.

An alternative explanation is that newborns might be born with functioning 'intermodal translation' - connection between the sensory channels of vision and proprioception (the sense of one's own body part positions in space). A close connection is needed between these channels, for an infant to master basic sensorimotor tasks such as reaching and grasping. But it's not been clear just how early this sensorimotor coordination might come online. Looking at a baby under 6 weeks age, doesn't seem like they have a lot of coordination going on.

But perhaps a skill like reaching and grasping isn't the first use which intermodal translation is put to. A tight and rich connection between visual perception and proprioception could also serve as a link between an infant seeing an adult's facial gesture, and the infant reproducing the same facial gesture. "In the case of the neonate, we do not have to posit some prior internal cognition that the infant is attempting to express or externalize through imitation. The infant has seen something, a facial gesture, and is expressing what she/he has seen, by taking up the capacity the infant has for that expressive movement on her/his own face."

That is, the infant doesn't need to use an abstract mental representation of the facial gesture she/he has just seen. The infant can skip that and go straight to a physical representation of it instead (on her/his own face).

If this intermodal translation idea is right, then it's likely that mirror neurons play a role. Mirror neurons, found in monkeys, are neurons which are active both when a monkey performs a particular motor action, and when the monkey sees another monkey perform that action. It's likely that mirror neurons operate in the human brain also (though their purported role has been overhyped, de rigeur for neuroscience findings).

Interesting stuff. But what then is the purpose of neonatal imitation? An obvious possibility is that it might have the "function of maintaining adult/infant social interaction until infants are capable of intentionally influencing such interactions themselves."

Ho hum. A more appealing explanation (to me anyway) is that it might play a foundational role in an infant's early sense of self, of others, and of intersubjectivity. Mind you, current evolutionary theory apparently contends that few if any evolutionary innovations serve only one purpose - so maybe it's a bit of both. (This principle would then also apply to intermodal translation - necessary for both basic sensorimotor performance, and for foundational social cognition.)

Further reading:

Gallagher S, "How the Body Shapes the Mind" (2005) Oxford University Press.

Related papers:

Meltzoff AN and Moore MK, "Imitation of facial and manual gestures by human neonates" (1977) 198 Science 75.

Meltzoff AN and Moore MK, "Imitation, memory, and the representation of persons" (1994) 17 Infant Behavior and Development 83.

Jones SS, "The development of imitation in infancy" (2009) 364 Philosophical Transactions of the Royal Society B 2325.

Bjorklund DF, "A note on neonatal imitation" (1987) 7 Developmental Review 86.

Thursday, 6 February 2020

Antipsychotics - Risperidone

Risperidone is an appalling drug. Complications include irreversible involuntary movements, and rapid weight gain with severe metabolic derangement.

But the most surprising aspect of its increasing use, in increasingly young kids, is that it has no real therapeutic effect in this age group.

I assume that antipsychotics are genuinely therapeutic, in psychosis. That's the indication - schizophrenia - for which this drug class was developed. Auditory hallucinations, persecutory delusions, and illusions of malign external control over one's thoughts and actions, can be horrific experiences; antipsychotics can provide relief from that suffering.

But this isn't the role which antipsychotics play for children and (non-psychotic) adolescents. In Australia, the main 'indication' for Risperidone prescription in young kids is challenging behaviours in autistic children. (It's also given to non-autistic, non-psychotic adolescents, with extreme challenging/aggressive behaviours.)

The use of Risperidone in autistic children has government authority behind it, quite literally. Australia's Pharmaceutical Benefits Scheme specifically authorises its prescription in 'severe behavioural disturbances' in patients with Autism spectrum disorder under 18 years of age, 'under the supervision of a paediatrician or psychiatrist'.

Risperidone doesn't, however, promote any particular cognitive function or developmental ability, in autistic kids, or in kids of any sort. It blunts their thoughts and actions - it turns their overall cognitive-behavioural volume down. It does so very reliably, which is why it's so helpful in extreme, aggressive or self-injurious behaviours.

Its effectiveness in dampening down all undesirable thoughts, speech and actions, should in itself cause concern over the associated consequences for the young person's neurodevelopment and learning.

I see quite a few kids for whom someone started Risperidone a while ago, where it seems that the kid's ongoing ingestion of the antipsychotic hasn't featured as a major clinical issue for regular consideration, by the prescriber. A 'set and forget' approach. The change most often made, over the 6 months or 5+ years of repeat prescriptions, is a regular nudging up of the dose.

One question which has struck me, is - if an antipsychotic really is indicated for a child or adolescent, why is it almost never prescribed PRN (as needed)? Why does the current default plan seem to be to commence regular doses, as if these drugs have SSRI pharmacokinetics, which they don't? Olanzapine wafers have been used PRN with good effect in emergency departments, for years.

I assume that the reason that PRN use hasn't taken off, is that antipsychotics are just so reliably effective at controlling behaviours. Without adequate medical explanation and advice, it's natural for a parent or carer who sees an antipsychotic provide relief from extreme behaviours once, to wonder why that relief can't be sustained. This phenomenon of 'dosing creep' is common enough with stimulants for ADHD - initially judicious use, with breaks on weekends and holidays; but which over months-years slides steadily into daily administration of ever increasing doses. But with ADHD and stimulants, the problem behaviours targeted are often merely annoying to adults - disruptive wisecracks in the classroom, failure to comply with household chores etc. Whereas the behaviours for which antipsychotics are started are often extreme - punching, kicking, detailed death threats, property damage, you name it.

One trap is for a younger kid (6-10yo) to be started on Risperidone for extreme behaviours like this, but without adding either adequate parent/carer support and understanding, or expert clinician involvement, to look a bit deeper than the behaviours alone. Many parents in this situation will resort to purely physical containment strategies. But as the child grows up, that becomes less and less physically feasible - especially if the drug has caused massive weight gain. A particular warning is warranted - it's never a good idea for an adult parent/carer to sit on a child, to restrain or control them.

*****

PBS authorisations follow the advice of expert committees, made up of thought leaders in the relevant medical specialties. A while ago I went looking for the 'evidence base' of Risperidone's PBS approval, for use in autistic kids.

I think the 2002 NEJM paper shown in this post's header probably really kicked things off. It has now been cited 1424 times. Abstract Conclusion:
"Risperidone was effective and well tolerated for the treatment of tantrums, aggression, or self-injurious behavior in children with autistic disorder."

A key outcome measure was the "Irritability subscale of the Aberrant Behavior Checklist, as rated by the parent... and confirmed by a clinician". What more could an overworked paediatrician ask for?

But this doesn't look like good science to me. Antipsychotic use in profoundly autistic kids with severe self-injury might be justified, especially in the short term. But 'irritability'? That's not a core clinical concept in practice, it doesn't appear in DSM definitions either. It's a plain English word, as liable to motivated misuse as any other word.

I'm sure that Risperidone does reliably address any 'irritability' shown by autistic kids. Administration of adequate doses of a barbiturate, or of the anaesthetic agent Propofol, or for that matter of cheap brandy or gin, would also address irritability in any patient, in the short term. Handcuffs or a straitjacket would also be effective in most cases.

*****

The number of antipsychotic prescriptions to children continues to climb. Meanwhile, in the US, pharma firm Johnson and Johnson has paid over $10 billion in damages, between 2013 and 2019, for its marketing of Risperidone. I wonder how much of the drug's increasing popularity in Australia arises from the apparent respectability which PBS authority listing might evoke, in the minds of some practitioners.

I posted this image to Twitter once, a pharmacist accused me of misleading the hivemind by using a non-zero x-axis. So I referred him to the chart's author, Rupert Murdoch. I haven't heard from the colleague since.

There are intermittent signs of pushback against this trend. The peak Australasian developmental paediatric body, the NBPSA, is working on a policy paper on the use of psychotropic medications in children and adolescents; the draft looks good. It's hard to know how it'll all play out.

Would I argue for the current PBS authority indication for Risperidone to be rescinded? No - the antidote to misguided, simplistic, authoritarian control over clinical practice isn't just simplistic authoritarian control of a different flavour.

Real progress will come from better individual clinical practice, across the board. There are good reasons for optimism on this front.

Most commonly, in my experience, the problems which arise from the prescribing of psychotropics to kids have little to do with a doctor's ignorance or knowledge of noradrenaline receptor dynamics, or the drug's second-order pharmacokinetics, or any of that.

One basic but reliable clinical rule of thumb is to not start a kid on any psychotropic medication, until all the non-drug ducks are lined up for him/her (tonight's post is brought to you by Mangled Metaphors Pty Ltd). Most often this is a simple enough clinical concept, but a major real-life pain in the posterior. If you think an 8yo will benefit from stimulants, but he's already down on himself from getting in trouble all the time at school, then don't start the med trial until the kid has an appointment booked with a psych or OT who you know and trust.

Successful drug prescribing entails the provision of meaningful explanations to bamboozled parents, meaningful interdisciplinary collaboration, and deft management of one's own counter-transference. And most of all, it takes time.

Papers:

McCracken JT et al, "Risperidone in children with autism and serious behavioral problems" (2002) 347 New England Journal of Medicine 314.

Panagiotopoulos C et al, "First do no harm: Promoting an evidence-based approach to atypical antipsychotic use in children and adolescents" (2010) 19 Journal of the Canadian Academy of Child and Adolescent Psychiatry 124. [ http://www.bcchildrens.ca/mental-health-services-site/Documents/First%20Do%20No%20Harm.pdf ]

Sunday, 26 January 2020

Embodied cognition

I tried turning it off and then on again already!

'Embodied cognition' is cognition which is "deeply dependent upon features of the physical body of an agent, that is, when aspects of the agent's body beyond the brain play a significant causal or physically constitutive role in cognitive processing".

It provides an alternative way of understanding the human mind, to the prevailing cognitive science model. In the cognitive science model, the brain is like a computer, it receives information from its external senses, it processes that information, then it provides a (motor) output. It processes information through computation. Its job could be entirely performed instead by a (very powerful) computer).

I myself find a lot of embodied cognition theory and research compelling and illuminating, it feels closer to real-life to me than some cognitive science. At present, embodied cognition is a minority view, and it's also not a single group or research program, it covers many different groups, with many different (and sometimes conflicting) theories.

It can be tricky to describe, so let's take a look at a couple of examples.

*****

The outfielder problem

I'm not saying I entirely understand this diagram...

In cricket*, how does an outfielder know where to run, to catch a ball which has been hit high and far by the batsman/batswoman?

'Instinct'. 'Practice'. Yeah sort of, but I mean the deeper explanation. How does the brain work out exactly where to send its body, in time to catch the ball?

Given the ball's starting point, and an estimate of its direction and velocity soon after it was hit, the answer can be calculated, it's basic Newtonian mechanics. Does the brain do this? Does it turn the two-dimensional image which the eyes have sent it into a 3D model, calculate the ball's landing spot, and send the body there? This model has been proposed as an explanation.

But that's apparently not what happens. The way the brain really solves this physics problem is by taking a shortcut, one which reliably works.

It gets a bit complicated, and there's still debate about which shortcut is used in real life. As I understand it, the fielder uses a (presumably unconscious) heuristic, of running so that as they see it, the ball moves in a particular way, within their field of vision. "The fielder watches the flight of the ball; constantly adjusting her position in response to what she sees. If it appears to be accelerating upward, she moves back. If it seems to be accelerating downward, she moves forward."

This trick would be much easier to show someone, with a bat and ball out on a field, than to describe in words. Although the best outfielder in the world hasn't ever been either shown this trick, or had it described to them.

This all captures a central idea in embodied cognition - that just because a real-life problem can be solved by a computer, that doesn't mean that animal or human brains actually do so, like a computer. Computation can be 'offloaded' onto the body and the environment. We didn't start off as a modern computer in a sea cucumber body; the brain and the body evolved concurrently, and interdependently.

*Research actually refers to 'fly balls' in baseball, thanks a lot American cultural imperialism.

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Embodied simulation as a theory of language

Where does language come from? More specifically, what is the mechanism by which the human brain turns infants with no language into fluent speakers? You might think we'd have a clear answer to that by now, but far from it.

When behaviourist theory dominated, in the first half of the 20th century, it tried to explain language acquisition as merely the reinforced association of sound patterns (words) with objects and actions, handed down from one generation to the next, one behavioural training session at a time. Too easy.

Cognitive science, and Noam Chomsky especially, came along in the 1960s and ripped that all to shreds. Chomsky then, and Steven Pinker now, propose an innate, hardwired program for language, which the human brain has evolved - a 'generative grammar'. A really innate program - in the genes. Chomsky talked about 'the poverty of the stimulus', arguing that young kids can't possibly hear enough instances of words and grammar to work out the structure of a human language (the feat can indeed seem miraculous, if you think about it).

But then by this model, what base language does our genes program, which a child then turns into one of the thousands of human languages around? What is the language of thought itself? A 1975 book on the topic by a guy called Jerry Fodor was influential. Pinker later coined the term 'mentalese' for this postulated language of thought.

Some thinkers and researchers today don't believe in this model, however. And for what it's worth, neither do I.

One alternative theory of the neural/cognitive foundation of language is the 'embodied simulation' theory. By this theory, the way all our brains have attached a particular meaning to a word or utterance, is by associating that utterance with a particular sensorimotor experience. A particular sensorimotor experience which we have actually experienced in real life, once or repeatedly.

This theory is closely tied to the 'conceptual metaphor' theory, which argues that most thought (not just language) arises as metaphor; a literal meaning being (largely unconsciously) cognitively recycled for an abstract meaning. The conceptual metaphor that 'anger is fire' is an example - we might consider a remark to be 'inflammatory', without any affectation of poetry. It's argued that these connections to and from conceptual metaphors are so direct that they underlie common fallacies and biases. We might conceptualise linguistic expressions as 'containers for meaning', but that conceptual metaphor might leave us blind to the role which context plays, in determining the meaning of a particular expression in real life.

This can all get very complex and very philosophical, quite quickly. Modern researchers in language embodied simulation have, however, done some pretty cool experiments supporting their claims, which I won't go into here.

To get slightly off topic, I myself suspect that, as is the usually the case in child development, child language acquisition is neither predominantly innate (genes/brain), nor predominantly determined by the environment/body. It's not just some 50-50 split either. It's the product of millions of agent-environment interactions, occurring in real time.

Or, as someone more clever than me has put it (I forget who), the cause of child language acquisition is evenly split between 100% genetic cause and 100% environmental cause.

[The discussion above excludes many other important aspects and frameworks of understanding human language. Those other frameworks, looking at the question from a different angle (such as the social aspect, set out by Jerome Bruner and Michael Tomasello), are of course equally important in explaining language.]