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Boy Without A Cerebellum...Has No Cerebellum

A reader pointed me to this piece:

Boy Without a Cerebellum Baffles Doctors
Argh. This is going to be a bit awkward. So I'll just say at the outset that I have nothing against kids struggling with serious illnesses and I wish them all the best.


The article's about Chase Britton, a boy who apparantly lacks two important parts of the brain: the cerebellum and the pons. Despite this, the article says, Chase is a lovely kid and is determined to be as active as possible.

As I said, I am all in favor of this. However the article runs into trouble is where it starts to argue that "doctors are baffled" by this:

When he was 1 year old, doctors did an MRI, expecting to find he had a mild case of cerebral palsy. Instead, they discovered he was completely missing his cerebellum -- the part of the brain that controls motor skills, balance and emotions.

"That's when the doctor called and didn't know what to say to us," Britton said in a telephone interview. "No one had ever seen it before. And then we'd go to the neurologists and they'd say, 'That's impossible.' 'He has the MRI of a vegetable,' one of the doctors said to us."

Chase is not a vegetable, leaving doctors bewildered and experts rethinking what they thought they knew about the human brain.

They don't say which doctor made the "vegetable" comment but whoever it was deserves to be hit over the head with a large marrow because it's just not true. The cerebellum is more or less a kind of sidekick for the rest of the brain. Although it actually contains more brain cells than the rest of the brain put together (they're really small ones), it's not required for any of our basic functions such as sensation or movement.

Without it, you can still move, because movement commands are initiated in the motor cortex. Such movement is clumsy and awkward (ataxia), because the cerebellum helps to coordinate things like posture and gait, getting the timing exactly right to allow you to move smoothly. Like how your mouse makes it easy and intuitive to move the cursor around the screen.

Imagine if you had no mouse and had to move the cursor with a pair of big rusty iron levers to go left and right, up and down. It would be annoying, but eventually, maybe, you could learn to compensate.

From the footage of Chase alongside the article it's clear that he has problems with coordination, albeit he's gradually learning to be able to move despite them.

Lacking a pons is another kettle of fish however. The pons is part of your brainstem and it controls, amongst other things, breathing. In fact you (or rather your body) can survive perfectly well if the whole of your brain above the pons is removed; only the brainstem is required for vital functions.

So it seems very unlikely that Chase actually lacks a pons. The article claims that scans show that "There is only fluid where the cerebellum and pons should be" but as Steven Novella points out in his post on the case, the pons might be so shrunken that it's not easily visible - at least not in the place it normally is - yet functional remnants could remain.

As for the idea that the case is bafflingly unique, it's not really. There are no less than 6 known types of pontocerebellar hypoplasia caused by different genes; Novella points to a case series of children whose cerebellums seemed to develop normally in the womb, but then degenerated when they were born prematurely, which Chase was.

The article has had well over a thousand comments and has attracted lots of links from religious websites amongst others. The case seems, if you believe the article, to mean that the brain isn't all that important, almost as if there was some kind of immaterial soul at work instead... or at the very least suggesting that the brain is much more "plastic" and changeable than neuroscientists suppose.

Unfortunately, the heroic efforts that Chase has been required to make to cope with his disability suggest otherwise and as I've written before, while neuroplasticity is certainly real it has its limits.

Meditation vs. Medication for Depression

What's the best way to overcome depression? Antidepressant drugs, or Buddhist meditation?

A new trial has examined this question: Segal et al. The short answer is that 8 weeks of mindfulness mediation training was just as good as prolonged antidepressant treatment over 18 months. But like all clinical trials, there are some catches.

Right mindfulness, sammā-sati, is the 7th step on the Buddha's Nobel Eightfold Path of enlightenment. In its modern therapeutic form, however, it's a secular practice: you don't have to be a Buddhist to meditate here (but it presumably helps).

Mindfulness meditation is also branded nowadays as mindfulness-based cognitive behavioural therapy (MCBT), although how much it has in common with regular CBT is debatable. The technique is derived from the Buddhist tradition.

The essence of mindfulness is deceptively simple: you try to become a detached observer of your own feelings and thoughts. Rather than just getting angry, you notice the feelings of anger, without letting them take over. As I've written before, while this might sound easy, we're not always aware of our own feelings.

MCBT has attracted a lot of attention as a possible way of helping people with depression achieve relapse prevention. The idea is that if you can train people to become aware of depressive thoughts and feelings if they start to reappear, they'll be able to avoid being sucked into the cycle of depression.

The 160 patients in this trial were initially treated with antidepressants, starting with an SSRI, and if that didn't work, moving onto venlafaxine (up to 375 mg, as necessary, which is a serious dose) or mirtazapine for people who couldn't take the side effects. This is a sensible treatment regime, not one relying on low doses and doubtful drugs, as in many other antidepressant trials.

About half of the patients both stayed in the trial and achieved remission. After 5 months of sustained treatment, these 84 patients were randomized into 3 groups: continuation of their antidepressant, placebo pills, or mindfulness. The people who ended up on placebo had their antidepressants gradually replaced by sugar pills over a number of weeks, to avoid withdrawal effects.

Here's what happened:

People on placebo did very badly, with only 20% remaining well 18 months later. People who either stayed on the drugs, or who got the mindfulness training, did a lot better, with 70% staying well, and there were no differences between the two.

However here's the catch. This was only true of a sub-set of the patients, the ones who had an "unstable remission", meaning that when they were originally treated with drugs, their symptoms went up and down a bit. The "stable remission" people showed no benefits of either treatment, with the ones on placebo doing slightly better, if anything.

Overall, though, this is a decent study, and shows that, for some people, mindfulness can be helpful. A skeptic could complain that mindfulness was no better than medication, but it might have two advantages: cost, and side effects, though this would depend on the medication you were talking about (some are a lot more expensive, and more prone to side-effects, than others.) The mindfulness meditation also wasn't double-blind, so the benefits may have been placebo effects, but that could be said of almost any trial of psychotherapy.

I also wonder whether you'd do even better if you became all mindful and stayed on medication: this study had no combined-treatment group, unfortunately, but this is something to look into...

ResearchBlogging.orgSegal ZV, Bieling P, Young T, Macqueen G, Cooke R, Martin L, Bloch R, & Levitan RD (2010). Antidepressant Monotherapy vs Sequential Pharmacotherapy and Mindfulness-Based Cognitive Therapy, or Placebo, for Relapse Prophylaxis in Recurrent Depression. Archives of general psychiatry, 67 (12), 1256-64 PMID: 21135325

"Koran Burning"

According to the BBC:

Koran protests sweep Afghanistan... Thousands of protesters have taken to the streets across Afghanistan... Three people were shot when a protest near a Nato base in the north-east of the country turned violent.
Wow. That's a lot of fuss about, literally, nothing - the Koran burning hasn't happened. So what are they angry about? The "Koran Burning" - the mere idea of it. That has happened, of course - it's been all over the news.

Why? Well, obviously, it's a big deal. People are getting shot protesting about it in Afghanistan. It's news, so of course the media want to talk about it. But all they're talking about is themselves: the news is that everyone is talking about the news which is that everyone is talking about...

A week ago no-one had heard of Pastor Jones. The only way he could become newsworthy is if he did something important. But what he was proposing to do was not, in itself, important: he was going to burn a Koran in front of a handful of like-minded people.

No-one would have cared about that, because the only people who'd have known about it would have been the participants. Muslims wouldn't have cared, because they would never have heard about it. "Someone You've Never Heard Of Does Something" - not much of a headline.

But as soon as it became news, it was news. Once he'd appeared on CNN, say, every other news outlet was naturally going to cover the story because by then people did care. If something's on CNN, it's news, by definition. Clever, eh?


What's odd is that Jones actually announced his plans way back in July; no-one took much notice at the time. Google Trends shows that interest began to build only in late August, peaking on August 22nd, but then falling off almost to zero.

What triggered the first peak? It seems to have been the decision of the local fire department to deny a permit for the holy book bonfire, on August 18th. (There were just 6 English-language news hits between the 1st and the 17th.)

It all kicked off when the Associated Press reported about the fire department's decision on August 18th and was quickly followed up by everyone else; the AP credit the story to the local paper The Gainsville Sun who covered the story on the same day.

But in their original article, the Sun wrote that Pastor Jones had already made "international headlines" over the event. Indeed there were a number of articles about it in late July following Jones's original Facebook announcement. But interest then disappeared - there was virtually nothing about it in the first half of August, remember.

So there was, it seems, nothing inevitable about this story going global. It had a chance to become a big deal in late July - and it didn't. It had another shot in mid-August, and it got a bit of press that time, but then it all petered out.

Only this week has the story become massive. US commander in Afghanistan General Petraeus spoke out on September 6th; ironically, just before the story finally exploded, since as you can see on the Google Trends above, searches were basically zero up until September 7th when they went through the roof.

So the "Koran Burning" story had three chances to become front-page global news and it only succeeded on the third try. Why? The easy answer is that it's an immediate issue now, because the burning is planned for 11th September - tomorrow. But I wonder if that's one of those post hoc explanations that makes whatever random stuff that happened seem inevitable in retrospect.

The whole story is newsworthy only because it's news, remember. The more attention it gets, the more it attracts. Presumably, therefore, there's a certain critical mass, the famous Tipping Point, after which it's unstoppable. This happened around September 6th, and not in late July or mid August.

But there's a random factor: every given news outlet who might run the story, might decide not to; maybe it doesn't have space because something more important happened, or because the Religion correspondent was off sick that day, etc. Whether a story reaches the critical mass is down to luck, in other words.

The decision of a single journalist on the 5th or the 6th might well have been what finally tipped it.

We Really Are Sorry, But Your Soul is Still Dead

Over the past few weeks, Christian neurosurgeon Michael Egnor, who writes on Evolution News & Views, and atheist neurologist Steve Novella (Neurologica) have been having an, er, vigorous debate about what neuroscience can tell us about materialism and the soul. As reported in New Scientist, this is part of an apparant attempt to undermine the materialist position (that all mental processes are the product of neural processes), on the part of the same people who brought you Intelligent Design. Many are calling it the latest front in the Culture War.

A couple of days ago Denyse O'Leary, a Canadian journalist who writes the blog Mindful Hack(*), posted some comments from Egnor about the great Wilder Penfield and his idea of "double consciousness" (my emphasis)

[By stimulating points on the cerebral cortex with electrodes during surgery] Penfield found that he could invoke all sorts of things- movements, sensations, memories. But in every instance ... the patients were aware that the stimulation was being done to them, but not by them. There was a part of the mind that was independent of brain stimulation and that constituted a part of subjective experience that Penfield was not able to manipulate with his surgery.... Penfield called this "double consciousness", meaning that there was a part of subjective experience that he could invoke or modify materially, and a different part that was immune to such manipulation.
I generally find arguing about religion boring, and I've no wish to enlist in any Culture Armies (I'm British - we're a nation of Culture Pacifists), but I'm going to say something about this, because it's just bad neuroscience. Maybe there are good arguments against materialism, but this isn't one.

Unfortunately, neither O'Leary nor Egnor allow comments on their blogs, but immediately after posting this I emailed them both with a link to this post. We'll see what happens.

Anyway, Penfield, whom you can read about in great detail at Neurophilosophy, was a pioneer in the functional mapping of the cerebral cortex. He was a neurosurgeon, and as part of his surgical procedures he would systematically stimulate different points of the cerebral cortex with an electrode, so as to locate which areas were responsible for important functions and avoid damaging them. Michael Egnor, following Penfield, is correct that this kind of point stimulation of the cortex tends to evoke sensations or motor responses which are experienced by the patient as external. Point stimulation is not reported to be able to effect our "higher" mental faculties such as our beliefs, desires, decisions, and "will"; it might evoke a movement of the arm, say, but the subject will report that this felt like an involuntary reflex, not a willed action.

However, to take this as evidence for some kind of a dualism between a form of conciousness which can be manipulated via the brain and another, non-material level of conciousness which can't (the "soul" in other words), is like saying that because hammering away at one key of a piano produces nothing but an annoying noise, there must be something magical going on when a pianist plays a Mozart concerto. Stimulating a single small part of the brain is about the crudest manipulation imaginable; all we can conclude from the results of point-stimulation experiments is that some kinds of mental processes are not controlled by single points on the cortex. This should not be surprising, since the brain is a network of 100 billion cells; what's interesting, in fact, is that stimulating a few million of these cells with the tip of an electrode can do anything.

Neuroskeptic is frequently critical of fMRI, but one of my favorite papers is an fMRI study, Reading Hidden Intentions in the Human Brain. In this experiment the authors got volunteers to freely decide on one of two courses of action several seconds before they were required to actually do the chosen act. (It was deciding betweening adding vs. subtracting two numbers on a screen.) They discovered that it was possible to determine (albeit with less than 100% accuracy) what subjects were planning to do on any given trial, before they actually did it, through an analysis of the pattern of neural activity across a large area of the medial prefrontal cortex.

The green area on this image shows the area over which activity predicts the future action. Importantly, no one point on the cortex is associated with one choice over another, but the combination of activity across the whole area is (once you put it through some brilliant maths).

Based on this evidence, it's reasonable to suppose that we could manipulate human intentions if, instead of just one electrode, we had several thousand (or million), and if we knew exactly which pattern of stimulation to apply. Or to run with the piano analogy: we could play a wonderful tune if we were skilled enough to play the right notes in the right combinations in the right order.

In fact, there are plenty of things which already are known to alter "higher" processes. At the correct doses, acetylcholine receptor antagonists such as scopolamine and atropine can produce a state of delerium with hallucinations which are experienced as being indistingishable from reality. Someone might talk to a non-existent friend or try to smoke a non-existent cigarette, without any knowledge of having taken a drug at all. Erowid has many first-hand accounts from people who have taken such drugs "recreationally" (a very bad idea, as you'll gather if you read a few.)

Then there's psychiatric illness. Someone who's psychotic may hear voices and believe them to be real communications from God, or the dead, or a radio transmitter in his head. A bipolar patient in a manic state may believe herself to have incredible talents or supernatural powers and dismiss as nonsense any suggestion that this is a result of her illness. In general those suffering from acute abnormal mental states may behave in a manner which is completely out of character, or think and talk in bizarre ways, without being aware of doing so. This is called "lacking in insight".

We don't yet know the neurobiological basis of these states, but that they (often) have one is beyond doubt; give the appropriate drugs - or use electricity to induce seizures - and they (usually) vanish. Many people in the advanced phases of dementia, especially Alzheimer's disease, as a result of neurodegeneration, are similarly unaware of being ill - hence the sad sight of formerly intelligent men and women wandering the streets, not knowing how they got there. Brain damage, or stimulation of deep brain structures (not the cortex which Penfield studied), can lead to profound alterations in personality and emotion. To summarize - if you seek the soul in the data of neuroscience, you will need to look harder than Penfield did.

Links : Sorry, But Your Soul Just Died - Tom Wolfe. A classic.

(*) - Mindful Hack - not to be confused with Mind Hacks.

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