December 2013 – Page 2

Hallucinated voices and the community inside us

I’ve long been fascinated by the experience of ‘hearing voices’ and long been baffled by the typical scientific approach to the experience.

As a result, I’ve just had a paper published in PLOS Biology that focus on one of the most striking but ignored aspects of hallucinated voices.

Here’s how I describe the central paradox in the paper:

Auditory verbal hallucinations, the experience of “hearing voices”, present us with an interesting paradox: the experiences are generated from within a single individual but are typically experienced as a social phenomenon—that is, a form of communication from another speaker.

Current theories attempt to explain auditory verbal hallucinations as alterations to individualistic information processing—namely, misattributions of internal thoughts as external phenomena due to biases in cognitive monitoring.

The fact that voices stem from an internal source is, of course, clear, but the typical experience of “hearing voices” is not that thoughts seem to be “spoken aloud” but that hallucinated voices have a social identity with clear interpersonal relevance. In other words, voices are as much hallucinated social identities as they are hallucinated words or sounds.

The article discusses the psychology and neuroscience of social processing in the experience of hearing voices and suggests how we can begin to consider this as a central component of the experience in terms of scientific research.

It’s an academic article but should hopefully be fairly accessible to most people with an interest in the science of hallucinations.

Enjoy!

Link to article ‘A Community of One’ on social cognition and hearing voices.

London’s Shuffle Festival is back

London’s film, food and science festival in an abandoned psychiatric hospital is back as the Shuffle Festival kicks off its Winter run.

Hosted in the old buildings of St Clement’s Hospital the festival has an impressive programme including everything from Jarvis Cocker to Brian Cox.

There are also regular talks from working scientists including a couple of standout-looking ones on the neuroscience of religious experience and circadian rhythms.

There’s also a full film programme, DJs, a restaurant, music, theatre and an art gallery with a commissioned show.

As with the summer Shuffle Festival, the profits go to the East London Community Land Trust that will ensure that when the hospital gets redeveloped, affordable housing will be available to the local community. A welcome change from the usual practice of converting London’s old asylums into exorbitant luxury flats.

If it’s anything like last time, it should be awesome. And if you didn’t go in August, this may be your last chance to say you’ve experienced a festival in an abandoned Victorian-era asylum.

The full programme is at the link below. See you there!

Link to the Shuffle Festival.

A life in the day of a medical morphine addict

AddictionBlog has an amazing article by a doctor and recovering morphine addict that describes the experience of injection, rush and withdrawal.

It’s wonderfully written to the point of being painful and if you’re not good with needles, you’ll probably feel a bit queasy when reading it.

Heroin, by the way, is just the prodrug of morphine. In other words, the heroin molecule just gets broken down into morphine in the body and this is the form in which it arrives in the brain.

But because each heroin molecule gets transformed into two morphine molecules (hence the medical name for heroin – diamorphine) the feeling can be a little different because the increased concentration can apparently make the high more intense.

Neurochemically, however, the action in each opioid receptor is the same.

As morphine is used more widely in medicine than diamorphine, it is more likely to be abused by doctors and turn up in cases of addiction.

As we’ve discussed previously, addiction and abuse of medical drugs by doctors is linked to clinical speciality – likely due to both knowledge of and access to particular compounds.

The AddictionBlog article is a strikingly written, honest, detailed and psychologically insightful piece if you want a look into this curious corner of medical drug abuse.

Link to ‘What it’s like to take and withdraw from morphine’

Are men better wired to read maps or is it a tired cliché?

By Tom Stafford

The headlines

The Guardian: Male and female brains wired differently, scans reveal

The Atlantic: Male and female brains really are built differently

The Independent: The hardwired difference between male and female brains could explain why men are ‘better at map reading

The Story

An analysis of 949 brain scans shows significant sex differences in the connections between different brain areas.

What they actually did

Researchers from Philadelphia took data from 949 brain scans and divided them into three age groups and by gender. They then analysed the connections between 95 separate divisions of each brain using a technique called Diffusion Tensor Imaging.

With this data they constructed “connectome” maps, which show the network of the strength of connection between those brain regions.

Statistical testing of this showed significant differences between these networks according to sex – the average men’s network was more connected within each side of the brain, and the average women’s network was better connected between the two hemispheres. These differences emerged most strongly after the age of 13 (so weren’t as striking for the youngest group they tested).

How plausible is this?

Everybody knows that men are women have some biological differences – different sizes of brains and different hormones. It wouldn’t be too surprising if there were some neurological differences too. The thing is, we also know that we treat men and women differently from the moment they’re born, in almost all areas of life. Brains respond to the demands we make of them, and men and women have different demands placed on them.

Although a study of brain scans has an air of biological purity, it doesn’t escape from the reality that the people having their brains scanned are the product of social and cultural forces as well as biological ones.

The research itself is a technical tour-de-force which really needs a specialist to properly critique. I am not that specialist. But a few things seem odd about it: they report finding significant differences between the sexes, but don’t show the statistics that allow the reader to evaluate the size of any sex difference against other factors such as age or individual variability. This matters because you can have a statistically significant difference which isn’t practically meaningful. Relative size of effect might be very important.

For example, a significant sex difference could be tiny compared to the differences between people of different ages, or compared to the normal differences between individuals. The question of age differences is also relevant because we know the brain continues to develop after the oldest age tested in the study (22 years).

Any sex difference could plausibly be due to difference in the time-course of development between men and women. But, in general, it isn’t the technical details which I am equipped to critique. It’s a fair assumption to believe what the researchers have found, so let’s turn instead to how it is being interpreted.

Tom’s take

One of the authors of this research, as reported in The Guardian, said “the greatest surprise was how much the findings supported old stereotypes”. That, for me, should be a warning sign. Time and time again we find, as we see here, that highly technical and advanced neuroscience is used to support tired old generalisations.

Here, the research assumes the difference it seeks to prove. The data is analysed for sex differences with other categories receiving less or no attention (age, education, training and so on). From this biased lens on the data, a story about fundamental differences is also told. Part of our psychological make-up seems to be to want to assign essences to things – and differences between genders is a prime example of something people want to be true.

Even if we assume this research is reliable it doesn’t tell us about actual psychological differences between men and women. The brain scan doesn’t tell us about behaviour (and, indeed, most of us manage to behave in very similar ways despite large differences in brain structure and connectivity). Bizarrely, the authors seem also to want to use their analysis to support a myth about left brain vs right brain thinking. The “rational” left brain vs the intuitive’ right brain is a distinction that even Michael Gazzaniga, one of the founding fathers of “split brain” studies doesn’t believe any more.

Perhaps more importantly, analysis of how men and women are doesn’t tell you how men and women could be if brought up differently.

When the headlines talk about “hardwiring” and “proof that men and women are different” we can see the role this research is playing in cementing an assumption that people have already made. In fact, the data is silent on how men and women’s brains would be connected if society put different expectations on them.

Given the surprising ways in which brains do adapt to different experiences, it is completely plausible that even these significant “biological” differences could be due to cultural factors.

And even reliable differences between men and women can be reversed by psychological manipulations, which suggests that any underling biological differences isn’t as fundamental as researchers like to claim.

As Shakespeare has Ophelia say in Hamlet: “Lord, we know what we are, but know not what we may be.”

Sophie Scott of UCL has some technical queries about the research – one possibility is that movements made during the scanning could have been different between the sexes and generated the apparent differences in the resulting connectome networks.

Another large study, cited by this current paper, found no differences according to sex.

Cordelia Fine’s book, Delusions of gender: how our minds, society, and neuro-sexism create difference provides essential context for looking at this kind of research.

UPDATE: Cordelia Fine provides her own critique of the paper

Tom Stafford does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published at The Conversation.
Read the original article.

Why the stupid think they’re smart

Psychologists have shown humans are poor judges of their own abilities, from sense of humour to grammar. Those worst at it are the worst judges of all.

You’re pretty smart right? Clever, and funny too. Of course you are, just like me. But wouldn’t it be terrible if we were mistaken? Psychologists have shown that we are more likely to be blind to our own failings than perhaps we realise. This could explain why some incompetent people are so annoying, and also inject a healthy dose of humility into our own sense of self-regard.

In 1999, Justin Kruger and David Dunning, from Cornell University, New York, tested whether people who lack the skills or abilities for something are also more likely to lack awareness of their lack of ability. At the start of their research paper they cite a Pittsburgh bank robber called McArthur Wheeler as an example, who was arrested in 1995 shortly after robbing two banks in broad daylight without wearing a mask or any other kind of disguise. When police showed him the security camera footage, he protested “But I wore the juice”. The hapless criminal believed that if you rubbed your face with lemon juice you would be invisible to security cameras.

Kruger and Dunning were interested in testing another kind of laughing matter. They asked professional comedians to rate 30 jokes for funniness. Then, 65 undergraduates were asked to rate the jokes too, and then ranked according to how well their judgements matched those of the professionals. They were also asked how well they thought they had done compared to the average person.

As you might expect, most people thought their ability to tell what was funny was above average. The results were, however, most interesting when split according to how well participants performed. Those slightly above average in their ability to rate jokes were highly accurate in their self-assessment, while those who actually did the best tended to think they were only slightly above average. Participants who were least able to judge what was funny (at least according to the professional comics) were also least able to accurately assess their own ability.

This finding was not a quirk of trying to measure subjective sense of humour. The researchers repeated the experiment, only this time with tests of logical reasoning and grammar. These disciplines have defined answers, and in each case they found the same pattern: those people who performed the worst were also the worst in estimating their own aptitude. In all three studies, those whose performance put them in the lowest quarter massively overestimated their own abilities by rating themselves as above average.

It didn’t even help the poor performers to be given a benchmark. In a later study, the most incompetent participants still failed to realise they were bottom of the pack even when given feedback on the performance of others.

Kruger and Dunning’s interpretation is that accurately assessing skill level relies on some of the same core abilities as actually performing that skill, so the least competent suffer a double deficit. Not only are they incompetent, but they lack the mental tools to judge their own incompetence.

In a key final test, Kruger and Dunning trained a group of poor performers in logical reasoning tasks. This improved participants’ self-assessments, suggesting that ability levels really did influence self-awareness.

Other research has shown that this “unskilled and unaware of it” effect holds in real-life situations, not just in abstract laboratory tests. For example, hunters who know the least about firearms also have the most inaccurate view of their firearm knowledge, and doctors with the worst patient-interviewing skills are the least likely to recognise their inadequacies.

What has become known as the Dunning-Kruger effect is an example of what psychologists call metacognition – thinking about thinking. It’s also something that should give us all pause for thought. The effect might just explain the apparently baffling self belief of some of your friends and colleagues. But before you start getting too smug, just remember one thing. As unlikely as you might think it is, you too could be walking around blissfully ignorant of your ignorance.

This is my BBC Future column from last week. The original is here.

A quarter century of All in the Mind

A new series of BBC Radio 4’s All in the Mind has just kicked off and to celebrate 25 years of broadcasting they’ve just had three great episodes looking back on the last quarter century of psychology, neuroscience and mental health.

Each make for a interesting discussion of how science and attitudes have changed.

As per BBC usual, you can access the streamed versions at the links above, but you have to go to an entirely separate page for the podcasts.

And because there are no separate podcast pages for specific episodes, I’ve linked them directly below. Here’s hoping that in the next 25 years, the BBC can fix their website.

mp3 of ’25 years of understanding the brain’
mp3 of ‘What has psychology research taught us in the last 25 years?’
mp3 of ‘How have attitudes to mental health changed in the last 25 years?’