Encephalon 46 arrives

The latest edition of the Encephalon psychology and neuroscience writing carnival has just appeared online, ably hosted by The Neurocritic.

A couple of my favourites include an article on the psychology of superstition from PodBlack and one hot from the Association for Psychological Science convention, where Cognitive Daily report on cognitive influences on calculation.

It’s a bumper edition and it even has some video of an intriguing experiment on ‘distributive justice’. You’ll have to read more to find out.

Link to Encephalon 46.

Hash high in cannabidiol but varies widely

In light of research showing that an ingredient in cannabis, cannabidiol, seems to actually reduce the risk of psychosis, I speculated previously on Mind Hacks whether smokers might be attracted to high-cannabidiol dope.

A study of UK street cannabis published in the Journal of Forensic Sciences suggests that cannabis resin (hashish) has the average highest rates of cannabidiol, while ‘skunk’ and imported herbal cannabis (weed) have the lowest.

For people who take cannabis, it’s not the cannabidiol that makes you ‘high’, it’s mainly a substance called tetrahydrocannabinol or THC.

There’s accumulating evidence that THC increases the risk of psychosis, while cannabidiol reduces it – so the ratio of the two substances in the street drug might give a ‘risk profile’ in terms of mental health.

‘Might’ is the operative word here, as the research is still preliminary and the studies are still largely correlational with regard to cannabidiol-to-THC ratio and psychosis-like symptoms.

However, if this does turn out to be case, the new survey of UK street cannabis suggests that, on average, cannabis resin has higher levels of cannabidiol, with the implication that this might be less risky in terms of developing schizophrenia or other psychotic disorders.

This finding is an average over all the samples, however, and the study also found that resin had quite a bit of variability with regards to cannabidiol-to-THC ratio.

However, imported herbal cannabis and skunk was generally very low in cannabidiol. Additionally, skunk also had about 6 times the THC content of normal weed, making it especially potent.

The study concludes:

This study suggests that cannabis in England in 2005 remains a very variable drug with unpredictable pharmacological and psychological activity. The potency (THC content) of the cannabis varies widely, as does the content of other cannabinoids, especially in herbal cannabis and cannabis resin. The average potency within the country appears to be increasing, but large variations remain within and between different areas of the country.

CBD affects the pharmacological qualities of THC and reduces it psychoactive potential. The relative proportions of THC and CBD in resin are wide ranging, supporting the view that the potential effects of resin cannot be judged by measuring the THC content alone. The resin samples were all similar in appearance and gave the user no indication of their cannabinoid content.

Of the three principle forms of cannabis, sinsemilla [skunk] commonly had the highest THC content and almost totally lacked CBD. Had CBD been present it would have reduced the psychoactive potential of this material. In addition to having increased in potency, sinsemilla also appears to have become the most widely used form of cannabis. The current trends in cannabis use suggest that those susceptible to the harmful psychological effects associated with THC are at ever greater risk. This is due to the combined rise in potency and popularity of sinsemilla and the absence of CBD in this product.

The lead scientist in the study is called Professor Potter. Do with that fact as you will.

Link to abstract of Journal of Forensic Sciences study.

Placebo is not what you think

The New York Times covers an interesting development in the world of consumer medicine – a company selling placebos to consumers that they can use to ease their children’s ills.

For doctors, the use of placebos to treat medical conditions is explicitly banned by most medical associations but their use is widely debated.

Thousands of clinical trials have shown us that placebo is one of the most effective and safest of medicines (although it is not entirely without side-effects).

However, it is also one of the most misunderstood of treatments.

An article in this month’s Journal of the Royal Society of Medicine (which has been debating placebo over the past year or two) dispels some of the myths.

The placebo effect is usually equated with the average response of patients receiving placebo controls in randomized trials. However, it’s not quite that simple.

For example, not every improvement that happens after someone is given a placebo treatment is the ‘placebo effect’ (some symptoms will just get better by themselves) and not every improvement after medication is the active effect of the drug, some of that will be ‘placebo effect’ too.

Placebos are not ‘ineffective’. In fact, when three condition trials are run (no treatment vs placebo vs medical treatment), placebo consistently out performs ‘no treatment’ and of course, not uncommonly, the medical treatment condition as well.

Placebos are not a ‘non-specific’ treatment. A study on people who take the dopamine-boosting drug L-DOPA for Parkinson’s disease but who took a placebo L-DOPA pill, showed almost identical brain changes, as if they’d taken the real thing.

Furthermore, studies done in the 1970s showed that when heroin users inject water (sometimes done deliberately to alleviate cravings when drugs are in short supply), they can experience drug-like euphoria and have been observed to show opiate-like physiological signs such as pupil constriction.

This last point also demonstrates that placebo is not solely about expectancy, belief or ‘being fooled’, as the heroin users knew they were injecting themselves with water. Conditioned responses play a role.

This can also be seen from the fact that these specific effects of placebo tend to fade after a while, as the conditioning becomes extinguished.

The fact that placebo can be a relatively safe, effective, and sometimes selective treatment has led some to argue that doctors should be able to use it officially (although, of course, many use it unofficially).

Law professor Adam Kolber (who you may know from the excellent Neuroethics and Law blog) wrote a fascinating paper last year that reviewed the research and argued that in limited circumstances, placebos could be ethically used.

The article is available online and I really recommend reading the ‘Avoiding Deception’ section if nothing else – for series of recommendations on how placebo could be used without straight up deception.

Link to NYT on buy-your-own placebos for kids.
Link to JRSM article on placebo. Full text here (thanks Ines!).
Link to Adam Kolber’s article (scroll down for free full text download).

Spellbound by the box

A quote from the sardonic Alfred Hitcock where he notes the curious interaction between mind doctors and the moving image:

“Television has done much for psychiatry by spreading information about it, as well as contributing to the need for it.”

I suspect he was commenting on concerns about negative effects of television, although I wonder whether he still might say the same, in light of the enduring influence of pharmaceutical adverts and claims of disease mongering.

Hitchcock himself was famously fascinated by the psychiatry of the day, and his films are well known for containing Freudian themes.

The most obvious was Spellbound, which featured psychiatrists, a psychoanalytic plot, and a symbolic dream sequence designed by Salvador Dalí.

Free choice and the female science divide

The Boston Globe has a provocative article that sheds some new light on the old debate over why there are so few women in maths and physical science subjects. One important factor seems to be that they simply choose other professions, but if you think this answer is too simplistic, there may be more to it than meets the eye.

It no longer seems to be the case that women are being explicitly blocked from maths, physics and engineering jobs, although the number of women in these professions is still very small.

One strong argument for why women are in the minority is that they suffer from the effects of implicit sexism, a system designed to take advantage of male attributes and life choices.

Some argue that the lack of support and consideration for women’s lives puts them off, and so they decide against what seems like a bad option.

However, the article presents an interesting piece of evidence against this as being the major influence.

In her controversial new book, “The Sexual Paradox: Men, Women, and the Real Gender Gap,” [Susan] Pinker gathers data from the journal Science and a variety of sources that show that in countries where women have the most freedom to choose their careers, the gender divide is the most pronounced.

The United States, Norway, Switzerland, Canada, and the United Kingdom, which offer women the most financial stability and legal protections in job choice, have the greatest gender split in careers. In countries with less economic opportunity, like the Philippines, Thailand, and Russia, she writes, the number of women in physics is as high as 30 to 35 percent, versus 5 percent in Canada, Japan, and Germany.

“It’s the opposite of what we’d expect,” says Pinker. “You’d think the more family-friendly policies, and richer the economy, the more women should behave like men, but it’s the opposite. I think with economic opportunity comes choices, comes freedom.”

If the gender gap in many fields has its roots in women’s own preferences, that raises a new line of questions, including the most obvious: Why do women make these choices? Why do they prefer different kinds of work? And what does “freedom of choice” really mean in a world that is still structured very differently for men and women?

Of course, this doesn’t deny that there are still other reasons why women might be put off these careers (lack of female role models, perception / effect of a ‘boys club’ etc) but it’s interesting that support for female physical scientists seems not to correlate with their numbers.

The article also mentions an interesting point that women with high maths ability tend to have good verbal ability (meaning they have a much wider potential choice of careers) whereas this is less often the case with men. In essence, the article argues that women would rather select jobs with more human contact.

It’s probably worth saying that in the life sciences, females predominate. In fact, in psychology, men are typically outnumbered 10-1. Clinical psychology tends to be even more extreme.

Despite the vanishingly small number of male psychology undergraduates, I’ve never heard of any effort to recruit or attract more males to the subject.

I’m always curious as to why having few males in life sciences doesn’t seem to bother people but having few females in maths or physics does.

Can’t we have some equality in our equality?

Link to Boston Globe article on women in science and engineering.

Like a bullet in the head

Neurophilosophy has collected some of the most unusual cases of penetrating brain injury from the medical literature, with x-rays that illustrate how some of the most curious objects can end up on the wrong side of the bony brain protector.

You may recognise a couple that we’ve noted before on Mind Hacks, but this is a far more complete and frankly quite surprising collection.

The most amazing is the case of a “32-year-old Caucasian male with a history of repeated self-injury drilled a hole in his skull using a power tool and subsequently introduced intracerebrally a binding wire from a sketchpad”.

A striking, and, in some places, stomach churning collection of case studies.

Link to Neurophilosophy on unusual penetrating brain injuries.

Mental illness following The Exorcist

Horror movie The Exorcist remains one of cinema’s darkest and most frightening classics. So great was its power that rumours circulated about viewers running in fear, feinting, or even going mad after seeing the film. In fact, it caused such concern that it was discussed in the medical literature for its possible role in triggering mental illness.

In 1975 psychiatrist James Bozzuto wrote an article for the Journal of Nervous and Mental Disease entitled ‘Cinematic Neurosis Following The Exorcist’ that reported four cases of previously untroubled people who seemed to develop psychiatric difficulties after watching the film.

I’ll return to the case reports in a moment, but it’s probably worth mentioning that Bozzuto was not alone in discussing the possible ‘destabilising’ effect of the film. In fact, his commentary was remarkably reserved in comparison to some of his contemporaries.

A 1974 Time magazine article quoted some of his less inhibited colleagues:

After seeing the film, two young Chicagoans required hospitalization. “They’re way out in leftfield,” said Dr. Louis Schlan, psychiatrist and medical director of Riveredge Hospital in Forest Park, Ill. “They see themselves possessed by Satan.”

Many others who have seen the film experience nightmares, hysteria and an undefined, but nevertheless profound apprehension. “It is dangerous for people with weak ego control,” explains Dr. Vladimir Piskacek, a Manhattan sociologist and psychiatrist, “but it would not cause psychosis.” Small children may suffer from hallucinations after seeing The Exorcist, but Dr. Piskacek doubts that the film would permanently impair even an immature mind.

Predictably, there are widespread objections to the film’s R rating, which permits youths under 17 to see it if accompanied by a parent. Manhattan Child Psychiatrist Hilde Mosse warns that the film provides a “deadly mixture of sex, violence and evil. The idea that we can solve our problems by magic instead of by rational solutions is destructive. I lived through this before Hitler came to power. He said, ‘Listen to the language of your pure Germanic blood, your unconscious.’ The Jews in Germany then became the devil to be exorcised. The only thing The Exorcist can do,” Dr. Mosse concludes emphatically, “is to pull young people down to a primitive level.”

With Hitler, hallucinating children and Satanic possession being invoked in relation to the film, it’s no wonder that people had anxieties about its influence.

Bozzuto’s explanation for his four case studies is perhaps a little mundane in comparison, but the influence of the media hysteria is plain to see.

One case is particularly striking, owing to gentleman’s florid magical thinking about the Devil and his possible malign influence.

Case 4. Mr. Lyle H. was a 24-year-old black male who initially came to the emergency room for three visits approximately 1 month after seeing “The Exorcist”. At that time, he complained of flashbacks and of getting “nervous”, especially with his two children and his wife; he was frightened that his 5-year-old daughter was possessed, had insomnia, and felt that certain people “looked strange”. He was given Vallium and referred to the Psychiatric Clinic. After being contacted for his first interview, he was fearful of coming for he felt that the therapist may have been involved with the Devil.

The patient stated that he knew little about the movie but had seen it discussed on a TV talk show before. He went with his wife and another couple. He was so upset during the movie that he had to walk out, and afterward he was frightened, feeling that the Devil “would come”. He had immediate insomnia, 15-pound weight loss over the past month, and numerous nightmares of vampires chasing women with himself interfering. He could not look people directly in the eye for fear he might imagine them to be devils…

Also, since seeing the movie, he complained of a stiff neck which he related to an identification with the girl in the movie. He was afraid to use a razor that his brother-in-law had given him because it might be stolen and it would imply he had done something wrong and would therefore be like the Devil.

Bozzuto suggests that each of his patients was already under significant pressure and the film was the last stressful straw that broke the camel’s back.

He also suggests, invoking the spirit of Freud, that the movie’s theme of losing control to the love-hate figure of the Devil may have had special significance for the four, each of which was apparently struggling with an ambivalent relationship.

According to Bozzuto, the similarity triggered repressed feelings, leading to an emotional crisis and a subsequent breakdown.

While the cases remain entirely anecdotal, it’s interesting that they made it into print at all, considering that almost all films have the potential to trigger emotional crises in some.

The fact that the issue of ‘Exorcist madness’ was considered serious enough to appear in a medical journal is more likely testament to the fact that the film touched a raw nerve in the America of the 1970s, than the fact that it raised the hackles of some of its audience members.

Link to PubMed entry for ‘Cinematic neurosis following The Exorcist’.
Link to Time article ‘Exorcist fever’.