Annette Karmiloff-Smith has left the building

The brilliant developmental neuropsychologist Annette Karmiloff-Smith has passed away and one of the brightest lights into the psychology of children’s development has been dimmed.

She actually started her professional life as a simultaneous interpreter for the UN and then went on to study psychology and trained with Jean Piaget.

Karmiloff-Smith went into neuropsychology and starting rethinking some of the assumptions of how cognition was organised in the brain which, until then, had almost entirely been based on studies of adults with brain injury.

These studies showed that some mental abilities could be independently impaired after brain damage suggesting that there was a degree of ‘modularity’ in the organisation of cognitive functions.

But Karmiloff-Smith investigated children with developmental disorders, like autism or William’s syndrome, and showed that what seemed to be the ‘natural’ organisation of the brain in adults was actually a result of development itself – an approach she called neuroconstructivism.

In other words, developmental disorders were not ‘knocking out’ specific abilities but affecting the dynamics of neurodevelopment as the child interacted with the world.

If you want to hear more of Karmiloff-Smith’s life and work, her interview on BBC Radio 4’s The Life Scientific is well worth a listen.

Link to page of remembrance for Annette Karmiloff-Smith.

echo chambers: old psych, new tech

If you were surprised by the result of the Brexit vote in the UK or by the Trump victory in the US, you might live in an echo chamber – a self-reinforcing world of people who share the same opinions as you. Echo chambers are a problem, and not just because it means some people make incorrect predictions about political events. They threaten our democratic conversation, splitting up the common ground of assumption and fact that is needed for diverse people to talk to each other.

Echo chambers aren’t just a product of the internet and social media, however, but of how those things interact with fundamental features of human nature. Understand these features of human nature and maybe we can think creatively about ways to escape them.

Built-in bias

One thing that drives echo chambers is our tendency to associate with people like us. Sociologists call this homophily. We’re more likely to make connections with people who are similar to us. That’s true for ethnicity, age, gender, education and occupation (and, of course, geography), as well as a range of other dimensions. We’re also more likely to lose touch with people who aren’t like us, further strengthening the niches we find ourselves in. Homophily is one reason obesity can seem contagious – people who are at risk of gaining weight are disproportionately more likely to hang out with each other and share an environment that encourages obesity.

Another factor that drives the echo chamber is our psychological tendency to seek information that confirms what we already know – often called confirmation bias. Worse, even when presented with evidence to the contrary, we show a tendency to dismiss it and even harden our convictions. This means that even if you break into someone’s echo chamber armed with facts that contradict their view, you’re unlikely to persuade them with those facts alone.

News as information and identity

More and more of us get our news primarily from social media and use that same social media to discuss the news.

Social media takes our natural tendencies to associate with similar minded people and seek information that confirms and amplifies our convictions. Dan Kahan, professor of law and psychology at Yale, describes each of us switching between two modes of information processing – identity affirming and truth seeking. The result is that for issues that, for whatever reasons, become associated with a group identity, even the most informed or well educated can believe radically different things because believing those things is tied up with signalling group identity more than a pursuit of evidence.

Mitigating human foibles

Where we go from here isn’t clear. The fundamentals of human psychology won’t just go away, but they do change depending on the environment we’re in. If technology and the technological economy reinforce the echo chamber, we can work to reshape these forces so as to mitigate it.

We can recognise that a diverse and truth-seeking media is a public good. That means it is worth supporting – both in established forms like the BBC, and in new forms like Wikipedia and The Conversation.

We can support alternative funding models for non-public media. Paying for news may seem old-fashioned, but there are long-term benefits. New ways of doing it are popping up. Services such as Blendle let you access news stories that are behind a pay wall by offering a pay-per-article model.

Technology can also help with individual solutions to the echo chamber, if you’re so minded. For Twitter users, let’s you view the feed of any other Twitter user, so if you want to know what Nigel Farage or Donald Trump read on Twitter, you can. (I wouldn’t bother with Trump. He only follows 41 people – mostly family and his own businesses. Now that’s an echo chamber.)

For Facebook users, is a browser extension that shows the political biases of your friends and Facebook newsfeed. If you want a shortcut, this Wall Street Journal article puts Republican and Democratic Facebook feeds side-by-side.

Of course, these things don’t remove the echo chamber, but they do highlight the extent to which you’re in one, and – as with other addictions – recognising that you have a problem is the first step to recovery.

The ConversationThis article was originally published on The Conversation. Read the original article.

rational judges, not extraneous factors in decisions

The graph tells a drammatic story of irrationality, presented in the 2011 paper Extraneous factors in judicial decisions. What it shows is the outcome of parole board decisions, as ruled by judges, against the order those decisions were made. The circles show the meal breaks taken by the judges.

parole_decisionsAs you can see, the decisions change the further the judge gets from his/her last meal, dramatically decreasing from around 65% chance of a favourable decision if you are the first case after a meal break, to close to 0% if you are the last case in a long series before a break.

In their paper, the original authors argue that this effect of order truly is due to the judges’ hunger, and not a confound introduced by some other factor which affects the order of cases and their chances of success (the lawyers sit outside the closed doors of the court, for example, so can’t time their best cases to come just after a break – they don’t know when the judge is taking a meal; The effect survives additional analysis where severity of prisoner’s crime and length of sentence are factored it; and so on). The interpretation is that as the judges tire they more and more fall back on a simple heuristic – playing safe and refusing parole.

This seeming evidence of the irrationality of judges has been cited hundreds of times, in economics, psychology and legal scholarship. Now, a new analysis by Andreas Glöckner in the journal Judgement and Decision Making questions these conclusions.

Glöckner’s analysis doesn’t prove that extraneous factors weren’t influencing the judges, but he shows how the same effect could be produced by entirely rational judges interacting with the protocols required by the legal system.

The main analysis works like this: we know that favourable rulings take longer than unfavourable ones (~7 mins vs ~5 mins), and we assume that judges are able to guess how long a case will take to rule on before they begin it (from clues like the thickness of the file, the types of request made, the representation the prisoner has and so on). Finally, we assume judges have a time limit in mind for each of the three sessions of the day, and will avoid starting cases which they estimate will overrun the time limit for the current session.

It turns out that this kind of rational time-management is sufficient to  generate the drops in favourable outcomes. How this occurs isn’t straightforward and interacts with a quirk of original author’s data presentation (specifically their graph shows the order number of cases when the number of cases in each session varied day to day – so, for example, it shows that the 12th case after a break is least likely to be judged favourably, but there wasn’t always a 12 case in each session. So sessions in which there were more unfavourable cases were more likely to contribute to this data point).

This story of claim and counter-claim shows why psychologists prefer experiments, since only then can you truly isolate causal explanations (if you are a judge and willing to go without lunch please get in touch). Also, it shows the benefit of simulations for extending the horizons of our intuition. Glöckner’s achievement is to show in detail how some reasonable assumptions – including that of a rational judge – can generate a pattern which hitherto seemed only explainable by the influence of an irrelevant factor on the judges decisions. This doesn’t settle the matter, but it does mean we can’t be so confident that this graph shows what it is often claimed to show. The judges decisions may not be irrational after all, and the timing of the judges meal breaks may not be influencing parole decision outcome.

Original finding: Danziger, S., Levav, J., & Avnaim-Pesso, L. (2011). Extraneous factors in judicial decisions. Proceedings of the National Academy of Sciences, 108(17), 6889-6892.

New analysis: Glöckner, A. (2016). The irrational hungry judge effect revisited: Simulations reveal that the magnitude of the effect is overestimated. Judgment and Decision Making, 11(6), 601-610.

Elsewhere I have written about how evidence of human irrationality is often over-egged : For argument’s sake: evidence that reason can change minds


Is psychosis an ‘immune disorder’?

A fascinating new study has just been published which found evidence for the immune system attacking a neuroreceptor in the brain in a small proportion of people with psychosis. It’s an interesting study that probably reflects what’s going to be a cultural tipping point for the idea of ‘immune system mental health problems’ or ‘madness as inflammation disorder’ but it’s worth being a little wary of the coming hype.

This new study, published in The Lancet Psychiatry, did blood tests on people who presented with their first episode of psychosis and looked for antibodies that attack specific receptors in the brain. Receptors are what receive neurotransmitters – the brain’s chemical signals – and allow information to be transferred around the nervous system, so disruption to these can cause brain disturbances.

The most scientifically interesting finding is that the research team found a type of antibody that attacks NMDA receptors in 7 patients (3%) out of 228, but zero controls.

The study found markers for other neuroreceptors that the immune system was attacking, but the reason the NMDA finding is so crucial is because it shows evidence of a condition called anti-NMDA receptor encephalitis which is known to cause episodes of psychosis that can be indistinguishable from ‘regular’ psychosis but for which the best treatment is dealing with the autoimmune problem.

It was only discovered in 2007 but there has been a long-running suspicion that it may be the best explanation for a small minority of cases of psychosis which can be easily misdiagnosed as schizophrenia.

Importantly, the findings from this research have been supported by another independent study that has just been published online. The two studies used different ranges for the concentration of NMDA antibodies they measured, but they came up with roughly the same figures.

It also chimes with a growing debate about the role of the immune system in mental health. A lot of this evidence is circumstantial but suggestive. For example, many of the genes associated (albeit weakly) with the diagnosis of schizophrenia are involved in the immune system – particularly in coding proteins for the major histocompatibility complex.

However, it’s worth being a little circumspect about this new enthusiasm for thinking of psychosis as an ‘immune disorder’.

Importantly, these new studies did blood tests, rather than checking cerebrospinal fluid – the fluid that your brain floats around in which lies on the other side of the blood-brain barrier, so we can’t be sure that these antibodies were actually affecting the brain in everyone found to have them. It’s likely, but not certain.

Also, we’re not sure to what extent anti-NMDA antibodies contribute to the chance of developing psychosis in everyone. Certainly there are some cases where it seems to be the main cause, but we’re not sure how that holds for all.

It’s also worth bearing in mind that the science over the role of the genes associated with the schizophrenia diagnosis in the immune system is certainly not settled. A recent large study compared the role of these genes in schizophrenia to known autoimmune disorders and concluded that the genes just don’t look like they’re actually impacting on the immune system.

There’s also a constant background of cultural enthusiasm in psychiatry to identify ‘biomarkers’ and anything that looks like a clear common biological pathway even for a small number of cases of ‘psychiatric’ problem gets a lot of airtime.

Curiously, in this case, Hollywood may also play a part.

A film called Brain On Fire has just been shown to film festivals and is being tested for a possible big release. It’s based on the (excellent) book of the same name by journalist Susannah Cahalan and describes her experience of developing psychosis only for it later to be discovered that she had anti-NMDA receptor encephalitis.

Hollywood has historically had a big effect on discussions about mental health and you can be sure that if the movie becomes a hit, popular media will be alive with discussions on ‘whether your mental health problems are really an immune problem’.

But taking a less glitzy view, in terms of these new studies, they probably reflect that a small percentage of people with psychosis, maybe 1-2%, have NMDA receptor-related immune problems that play an important role in the generation of their mental health difficulties.

It’s important not to underestimate the importance of these findings. It could potentially translate into more effective treatment for millions of people a year globally.

But in terms of psychosis as a whole, for which we know social adversity in its many forms plays a massive role, it’s just a small piece of the puzzle.

Link to locked Lancet Psychiatry study.