Author: vaughanbell

Today is World Mental Health Day, and what could be a better way to celebrate a day of mental calm and tranquility than to ignite a blazing row at the core of psychiatry?

A group of mental health activists are pushing for the diagnosis of schizophrenia to be abolished.

Actually, the idea that schizophrenia is a single separate disorder is in a pretty shoddy state, but the argument is a textbook example of mixed agendas as the people who want to reject the label also reject the use of biological explanations in theories of mental illness, and those who argue most forcefully for the diagnosis of schizophrenia are usually heavily committed to biological psychiatry.

What gets lost, is that the validity of schizophrenia as a concept, and whether biological theories are useful, are separate issues.

This is probably because both sides seem to spend so much time trying to make us think that they’re not.

To get a good idea of what the diagnosis of schizophrenia describes in terms of our scientific understanding, the entry for schizophrenia on the OMIM database of medical conditions with genetic influences really says it all:

Schizophrenia is a psychosis, a disorder of thought and sense of self. Although it affects emotions, it is distinguished from mood disorders in which such disturbances are primary. Similarly, there may be mild impairment of cognitive function, and it is distinguished from the dementias in which disturbed cognitive function is considered primary. There is no characteristic pathology, such as neurofibrillary tangles in Alzheimer disease. Schizophrenia is a common disorder with a lifetime prevalence of approximately 1%. It is highly heritable but the genetics are complex. This may not be a single entity.

In other words, very little can be said with certainty. Any definition that finishes with the ominous “This may not be a single entity” suggests we really don’t understand much about the associated experiences.

So why does the argument over schizophrenia persist?

Mainly because the medical and legal systems are far more comfortable with cut-and-dry “you have it or you don’t” conditions than ones in which you might have a bit of this and a bit of that.

This is often due to the fact that the medical and legal systems have to make cut and dry decisions. To treat or not to treat, to detain or not to detain, and so on. These decisions become a lot easier when the supporting information is as simple as possible.

It also becomes a lot easier to market treatments for specific disorders. In fact, in many countries, drugs can only be licensed for specific disorders.

So, no diagnosis means that there’s no way of getting drugs licensed. This is why pharmaceutical companies have a vested interest in supporting the concept of schizophrenia.

In other words, the usefulness of the diagnosis of schizophrenia rests not only upon the supporting medical research, but also on its social function.

In fact, one of the ironies of the debate, is that the most recent research in molecular genetics (exactly the sort of biological approach that those against the diagnosis of schizophrenia are also opposed to) shows some of the best evidence that schizophrenia is not a discrete condition.

You can imagine that neither the drug companies nor the anti-schizophrenia-diagnosis mental health activists plaster these findings across their leaflets.

Link to article on molecular genetics of mental illness.
Link to Asylum Online on ‘Abolition of the Schizophrenia Label’.
Link to BBC News article on the debate.

Quality online cognitive science site Science and Consciousness Review has arisen phoenix-like from the ashes after a nasty database crash.

The outage removed it from the internet for several months, but it is now back in action, serving up the latest in news and views in consciousness and cognitive science research.

In fact, it’s just alerted me to the announcement of the 2007 visual illusion contest which also includes last year’s winners on their website.

Link to Science and Consciousness Review.

There’s an interesting piece on BBC News that has a different take on the two breastfeeding stories we ran recently that suggested that breastfeeding during the early years might aid brain development and reduce risk for mental illness.

A study published this week in the British Medical Journal suggests that the advantage of breastfeeding on baby’s intelligence could be explained not by the effect of breastmilk on the infant’s developing brain, but by the fact that women who breastfeed are more likely to have higher IQs.

This is perhaps because IQ is correlated with social and economic class, and people in these classes are generally more likely to follow health advice promoted in education campaigns.

Hence, these babies might just be more likely to inherit neurodevelopmental advantages from their mothers (IQ is known to be partially heritable), and are probably more likely to benefit from a range of other factors which better socioeconomic conditions bring.

I suspect that advantage seen in breastfed babies might be a combination of social and genetic factors, as well as the effects of breastmilk.

We know that good nutrition in the early years is crucial to good brain development and breastmilk is a tailor-made for the purpose.

However, the brain also develops through interaction with the environment, so this nutritional advantage has to be balanced against social and educational experience.

Link to BBC News story “Breast milk ‘does not boost IQ'”.
Link to abstract of original study from BMJ.

The BBC has a news story on the genetics of a disorder called trichotillomania (compulsive hair-pulling) that typifies the way genetics discoveries are reported in the media.

First sentence:

Scientists have identified gene mutations responsible for a psychiatric disorder that causes people to compulsively pull their own hair.

Way down the article:

Dr Allison Ashley-Koch, who also worked on the study, said numerous other genes were likely to contribute to the condition. She said: “The SLITRK1 gene could be among many other genes that are likely interact with each other and environmental factors to trigger trichotillomania and other psychiatric conditions.

No prizes for guessing which is the most accurate and which makes the best headline copy.

In almost any news story you read that says ‘gene found for psychiatric disorder X’ read ‘a gene has been identified which seems to explain some of the risk for developing X’ – unless it specifically says otherwise.

Link to BBC News article ‘Hair pulling disorder gene found’.
Link to more information on trichotillomania.