Placebo has strength in numbers

Photo by Flickr user anitacanita. Click for sourceWired has an excellent article on how the placebo effect is increasing in drug trials and how drug companies are trying to understand why. It’s an intriguing article but it conflates two distinct concepts of ‘placebo’ that need to be separated to fully understand the effect.

The term ‘placebo effect’ is used to refer to two things in the medical literature. The first is a statistical concept and it refers to the improvement in patients given an inactive treatment in a drug trial in comparison to those given the actual drug. The second is a psychological concept and it refers to improvement due to expectancy and belief.

If you’re not sure how these are different, you may be surprised to learn that you don’t need a mind to demonstrate the placebo effect – in fact, even rocks can show it.

Let’s say an oil tanker has sunk, the local beach is covered in oil, and you want to compare how effective two cleaning products are – the first, liquid soap, our active treatment, and the second water, our placebo.

So we randomly assign oily stones to a bucket of soapy water or to a bucket of water. It turns out that while stones in the soap condition become less oily, so do stones in the placebo condition, although, perhaps, the effect is weaker. Oil breaks down on its own, water movement disperses it, oxygenation happens. There’s a whole bunch of stuff which means our placebo ‘treats’ the stones.

Statistically we have a placebo effect, because in a trial anything which causes improvement not to do with the active treatment is chalked up to the placebo effect.

In humans, similar effects are at work. Most illnesses improve on their own, when we catch anything at its worst typically it will return to its normal state (an effect known as regression to the mean), people change their behaviour to become more healthy when they’re ill, and so on. None of these are to do with expectancy or beliefs about taking a pill.

But here’s the other thing. Because the statistical concept of placebo is drawn from the study data, the study itself has an effect.

For example, the strength of the placebo effect is measured relative to the active treatment. The Wired article says that placebo is getting stronger, which is another way of saying that the difference between placebo and the drug is getting smaller.

It turns out that the more rigorous the study the less strong the drug effect is, or, in other words, the stronger the placebo effect.

For example, we know that better designed and higher quality studies show smaller drug effects. This includes things as simple as randomisation. If your method for randomly allocating people to groups is more susceptible to bias, it’s more likely to produced biased results. Better randomisation improves the placebo effect, again, nothing to do with expectancy or belief.

So one reason why the placebo effect might be increasing is that studies are just more rigorous these days.

Of course, on top of all of these things, individual psychology plays a part as it adds improvement, and anything which leads to improvement gets captured by the statistical placebo effect.

However, the lab-based studies which investigate placebo look almost exclusively at the psychological placebo effect. They examine the effects of beliefs and expectations but usually carefully control the presence of the unpleasant thing, like pain, so it doesn’t naturally improve and you can’t change your behaviour like you would in real life.

You can’t explain the statistical placebo effect just with psychology. It’s part of it, but not the whole story.

So when I read the article which said that drug companies are busily doing lab studies to understand why the placebo effect is increasing I became a bit suspicious.

The first thing you’d do is look at how your studies have been run, not look at the psychology of belief. Drug companies undoubtedly know this. They’re masters of drug trial sleight-of-hand and know research methods inside out.

The article touches on a likely explanation – marketing. They would like to influence your beliefs so the drug works better for you, because once it’s on the market, it’s the customers’ experience that brings them back for more.

In an industry where genuinely new drugs are rare and most are just no-better copies of rival medications, your beliefs could make all the difference.

Link to Wired on the increasing placebo effect.
Link to previous Mind Hacks post on the psychology of placebo.

The sexual transformation delusion

Photo by Flickr user jcoterhal. Click for sourceMedical journal Epilepsy and Behavior has a curious case study of a female patient who had the experience of changing sex when she had a seizure.

The patient in question had a small tumour near the right amygdala and showed abnormal right temporal lobe activity on an EEG. Interestingly, when she had the experience of changing sex, she also experienced other females in the vicinity as also transforming into males.

She experienced a sensation of dull nausea rising from the epigastrium [abdomen] with concomitant fear, sometimes also accompanied by déjà vu, in isolation, several times per week. Occasionally this developed into a complex alteration of perception, which she explained as follows: ”I’m no longer feeling to be a female. I have the impression to transform into a male. My voice, for example, sounds like a male voice that moment. One time, when I looked down to my arms during this episode, these looked like male arms including male hair growth.”

This particular kind of perceptual disturbance was not restricted to herself, but also characterized her perception of female persons nearby during the episode: “One time another woman, a friend of mine, was in the same room, I perceived also her as becoming a male person including changing sound of her voice.” After introduction of anticonvulsive treatment with carbamazepine, only the elementary simple-partial phenomena of epigastric aura and déjà vu persisted. Secondary generalized tonic–clonic seizures never occurred.

Sex change delusions have been reported in the medical literature before, but usually in longer-term psychoses in people with diagnoses like schizophrenia, rather than occurring as a short-term effect of a seizure.

In fact, sex change delusions were reported by one of the most famous psychiatric patients in history: Daniel Schreber, a 19th century German judge who wrote about his experience of insanity in his book Memoirs of My Nervous Illness.

Among other experiences he describes how he believed that his mind was attracting ‘rays’ from God causing him feminising sensations of ‘voluptuousness’ which he noticed as female body changes.

Temporary sex change ‘delusions’ have also been created using hypnosis in highly hypnotisable people in two remarkable studies that attempt to understand how the mind justifies a belief clearly contrary to reality.

Link to DOI entry and summary of case study.

Ten year high

Photo by Flickr user MyDigitalSLRCamera. Click for sourceOriginally an academic project to study the science of happiness, positive psychology has spawned a hippy fringe of life coaching and self-help. In a thoughtful review of the field, The Chronicle of Higher Education looks at the state of the elation after its first decade in existence.

Positive psychology maintains a core of rigorous empirical science but it is clear from the article that there is considerable tension between those who simply want to investigate the building blocks of the good living and those who want to extend (and sometimes over-extend) the work into life guidance.

Although it has gained considerable respectability, the field is still treated with suspicion in some corners of mainstream psychology, not least because of the tendency for academia to privilege austere seriousness and to treat anything with mass appeal with elitist disdain.

But still there is a slightly evangelical feel to positive psychology which make some people uncomfortable.

Two of the field’s founders and most enthusiastic proponents became famous for some of the darkest and bleakest studies in psychology: Martin Seligman’s work on depression and learned helplessness was based on how some dogs give up trying to escape when repeatedly tortured with inescapable electric shocks and Philip Zimbardo’s prison experiment showed that respectable people can be turned into brutal abusers when the context encourages it.

Whether Seligman and Zimbardo feel they’re repenting for their dark past or not, many who associate with the field have the zeal of those reborn from a science previously obsessed with human misery.

The Chronicle article is a insightful look into both the science and culture of positive psychology, taking a particularly close look at the tensions which are shaping how we understand human growth and potential.

Link to Chronicle on 10 years of positive psychology (via @researchdigest).

Brain fibres

concertinapieces is a psychology student who makes wonderful crochet neurons that you can buy over the interwebs, although she warns that “your neuron may vary slightly in dendritic branches as no two are alike :)”

Her online shop has motor, bipolar and hippocampal pyramidal neurons that you can use to begin creating your reanimated textile zombie brain.

Actually, I quite fancy the idea of a crochet Purkinje neuron but I suspect it would need so much wool you’d need a truck to deliver it.

Might make for a great duvet though.

Multi media, we don’t need it do we?

Photo by Flickr user iPocrates. Click for sourcePeople who spend lots of time monitoring multiple sources of information are worse at switching between tasks and are less able to focus exclusively on single sources according to a new study published in the Proceedings in the National Academy of Sciences.

It’s a well designed, rigorous study of the type that we are sorely missing in the debate over the psychological effects of media which, sadly, often amounts to little more than hot air.

It’s also been picked up by hundreds of news sources, almost all of which miss the subtlety of what it’s actually telling us.

Here are some of the headlines that miss the point: Hi-tech addicts scrambling their brains; Multi-media use muddles the mind; and my favourite Electronic Multitaskers Not Really ‘Information Gods’ (damn you Microsoft, fooled again!)

The experiment compared groups of people who frequently monitor multiple media sources compared to those who do it rarely. Big media has picked up on the ‘multi media’ angle and has focused solely on digital technology but the study was much broader than this.

It divided groups into high and low ‘media multitaskers’ but ‘media’ included a whole bunch of sources, including:

print media, television, computer-based video (such as YouTube or online television episodes), music, nonmusic audio, video or computer games, telephone and mobile phone voice calls, instant messaging, SMS (text messaging), email, web surfing, and other computer-based applications (such as word processing).

In other words, listening to music while reading a book counts as ‘media multitasking’, as does chatting on the telephone while watching television, none of which need digital technology. In fact, you could have multitasked five out of the twelve activities (print, TV, music, nonmusic audio, phone calls) in the 1950s.

This is actually one of the study’s major advantages. It makes sense to look at how people monitor multiple sources in the real world rather restrict ourselves to the computer technology, because there is nothing necessarily distinctive about ‘digital media’. A digital radio is not psychologically different to an analogue one in terms of its output.

So the researchers compared the high and low multitaskers on several tasks looking at whether peripheral information affected performance on visual and memory monitoring tasks, and on a task-switching experiment.

High media multitaskers were generally more affected by peripheral information but this is not a bad thing in itself. You could interpret it as them being more distractable, or simply that they have a wider net of attention and are more able to pick up peripheral information. They might be open to noticing more stuff.

But the task-switching experiment was quite striking. Participants were presented with a letter and number combination, like “a6” or “i7” and were asked to do one of two tasks: one was to hit the left button if they saw an odd number and the right for an even; the other was to press the left for a vowel the right for a consonant.

They were warned before each letter-number combination appeared what the task was to be, but high multi-taskers responded on average half a second more slowly when the task was switched.

In reaction time terms, half a second is a very long time. Bruce Lee could have made mincemeat of you by then.

Of course, what we can’t tell from this study is whether heavy parallel media monitoring causes these effects, or whether people who are less able to exclusively focus and switch prefer more media concurrently. Maybe they’re actually absorbing more of it in total. We don’t know from this study.

Despite big media going off half-cocked, this is a valuable study because we need to start understanding how information technology affects us in our day-to-day life.

We have precious few of these studies and we need more.

Link to paper.
Link to DOI entry for same.
Link to great write-up from Not Exactly Rocket Science who beat me to the punch.

Learning reality in the first few months of life

Photo by Flickr user kton25. Click for sourceRadioLab has just released an excellent brief podcast on how babies’ experience of the world is quite different during the first months of life due to some startling differences in brain function that they rapidly lose.

It’s a discussion with developmental psychologist Charles Fernyhough who has pieced together the perceptual world of young children from studies on newborns.

It’s full of fascinating insights, like the fact that the lenses in the eyes of newborns have yet to acquired the yellow tint of adults which filters out blue light – so children see a much brighter whiter world.

One of the most surprising bits is about a phenomenon I’d never heard of before – something called sticky fixation – where babies lose control of their vision at about two months old and seem to lose the ability to look away from interesting things.

This seems to be due to the fact that vision is initially controlled by subcortical brain systems but about two months the control shifts to the cortex. During the ‘changeover’ the competition between the two systems seems to lead to the stalemate of sticky fixation.

It’s a really fascinating way to spend 10 minutes and I think virtually everything featured was quite new to me.

And if you’re wanting more about the fascinating science of baby development Edge has an interesting discussion with psychologist Alison Gopnik.

One interesting thing to note here is how Bayesian statistical models are now appearing everywhere in cognitive science as models of thought and behaviour.

Influential neuroscientist Karl Friston has been championing them as a ‘theory of everything’ for the brain for a couple of years now and they’re starting to be more widely accepted as you can see by the way Gopnik riffs about them with regards to infant psychology.

Link to RadioLab short ‘After Birth’.
Link to Edge on ‘Amazing Babies’ with Alison Gopnik.

You see us as you want to see us

The LA Times has a reflective piece on the late teen movie director John Hughes‘ vision of adolescence in light of today’s fashion for medicating teenagers:

“If the brooding, solitary Andie played by Ringwald in “Pretty in Pink” were in high school in 2009, it’s hard to imagine she wouldn’t be a candidate for anti-depression therapy. Likewise, if “The Breakfast Club,” which is about five teens serving time in Saturday detention, took place in a post-Prozac, post-Columbine America, Ally Sheedy’s mostly mute, kleptomaniac misfit would have undoubtedly been medicated, and Anthony Michael Hall’s character would have received a lot more than detention for bringing a flare gun to school. As for Ferris Bueller, the kid obviously needed Ritalin.

“I’m not suggesting that any of us were better off when legitimate disorders went unrecognized and untreated. But in a culture in which diagnoses sometimes seem to get handed out like conservation-awareness fliers in front of the supermarket, it’s worth asking ourselves if old-fashioned eccentricity — of the teen or adult variety — can too easily be supplanted by the ease of assigning a code from the Diagnostic and Statistical Manual. Hughes, who left the movie business in the early 1990s because he feared the impact Hollywood would have on his children, should be remembered not just for the way he appreciated weirdness but for the way he normalized it — not with pills but with paisley.”

The monologue that bookmarks The Breakfast Club, with the line “You see us as you want to see us – in the simplest terms, in the most convenient definitions”, succinctly captures how society’s view of youth changes and yet always stays the same.

For the current younger generation, the simplest terms are mostly taken from psychiatry. This will eventually change and our recurrent anxieties about the young will largely be expressed in the next most convenient definition.

As a society, we are strangely blind to the complexities of youth.

Link to LA Times piece ‘He made weird normal’ (via Furious Seasons).