Thursday, September 30, 2010

Psychosocial theory of ADHD does not blame parents

Sarah Boseley's report in the Guardian about the Lancet genetic study of ADHD, which concludes in the paper that ADHD is not purely a social construct, quotes Professor Anita Thapar, the senior author of the study, as saying that she hopes "that these findings will help overcome the stigma associated with ADHD". She's confident that ADHD is a genetic condition, which, to her mind, shows she was right that ADHD should not be dismissed as being due to bad parenting or poor diet.

Avoiding blaming the parents is commonly used as an argument for a biomedical view of ADHD and other mental disorders, such as schizophrenia. However, it's a misunderstanding of the psychosocial perspective to take this as its implication. Trying to understand why a child becomes hyperactive is several steps away from blaming anyone. There's no suggestion that there's any conscious intention to cause harm and there is no one-to-one causal connection. Understanding reasons is not the same as causal connections.

Wednesday, September 29, 2010

Oh no, not another neurobiological theory of depression

When I initially read Scicurious' posting on the Guardian Science blog, I wondered whether it was a spoof. But no, there are some references in the literature to antidepressants increasing neurogenesis in animals. Scicurious wonders whether this may be the mechanism of action of antidepressants, as she's given up on the low serotonin theory of depression.

Scicurious blogs at Neurotic Physiology. She makes clear her view on her About Scicurious page that "we have [now] discovered that all “neuroses” and psychiatric disorders have a physiological basis". I don't want to undermine her faith, but she should make it clear she's just promoting her belief and not call it science.

She notes that "antidepressants do work in some patients". As I've said in a previous post, the way in which they work may be merely as amplified placebos.

Sunday, September 26, 2010

Adult executive brain dysfunction

Felicia Wong, in a posting on the Healthy Minds. Healthy Lives. blog (the American Psychiatric Association’s online resource for mental health issues), refers favourably to a Wall Street Journal article on adult ADHD. As the article says, ADHD is "thought to be an imbalance in neurotransmitters, the chemical messengers that relay signals in the brain, particularly in the frontal cortex that governs planning and impulse control." Ivan K. Goldberg, a psychiatrist in New York City, who co-developed a commonly used screening test, is quoted as saying "What it really is is a disturbance of the executive functions of the brain".

Dr Wong recommends that those who suspect they have ADHD should have a thorough evaluation with a psychologist or psychiatrist. How do psychologists or psychiatrists know if there is an executive brain dysfunction? It's an hypothesis but how do we know whether it's true? Using the screening test co-developed by Dr Goldberg is not a diagnostic test, although there are rating scales used for diagnosing ADHD. But they're not measuring executive brain dysfunction. So what is being diagnosed when a diagnosis of adult ADHD is made and why link it to speculation about executive brain dysfunction? It's just a convenient way of viewing the world, isn't it?.

Thursday, September 23, 2010

Does it matter whether biomedical psychiatry is true or not?

Lesson 5 of the NIMH course curriculum on mental illness, mentioned in a previous post, looks at the problem from the diagnosed children's perspective. Like any other kid is a video in three parts.

Regarding their problem as caused by a brain disorder has helped to make sense of their situation for these young people. Biomedical psychiatry can provide a genuine order to the world. Does it matter whether it's true or not?

Sunday, September 19, 2010

Mental illness as faulty circuits in the brain

Research in mental health has moved on from chemical imbalances as the cause of mental illness to circuitry dysfunction in the prefrontal cortex, at least according to Thomas Insel, Director of NIMH. For example, in his article Disruptive insights in psychiatry: Transforming a clinical discipline, he says aspects of schizophrenia can be mapped onto dysfunction of dorsolateral prefrontal circuits that mediate executive function; depression appears to involve dysfunction in a region of the midline infragenual prefrontal cortex important for regulation of mood; OCD (obsessive-compulsive disorder) involves dysfunction in the orbitofrontal prefrontal cortex via its role in perseverative behaviours; and posttraumatic stress disorder (PTSD) can now be mapped to dysfunction in prefrontal circuits required for the extinction of fear.

There is of course some localisation of function in the brain but dynamic interactions between multiple regions produce thought, emotion and behaviour. It's a long step to mapping specific mental illnesses to dysfunction of brain circuits. Insel himself concedes that more research is needed.

Moreover, Insel clearly juxtaposes his concept of mental illness as brain disorder with psychological disorders caused by psychic trauma or conflict. He says we need to rethink our approaches to diagnosis, treatment, and professional training. So he's happy for his approach to encourage psychosurgery and intracranial brain stimulation.

He got an airing of his views in an article, Faulty circuits, for the popular Scientic American. His claim that neuroscience will revolutionise psychiatry is no different from the one made by modern psychiatry since its origins with the asylums. How many more blind alleys will psychiatric research lead us down? Faulty brain circuits in mental illness are as much of a myth as biochemical imbalances.