Mind Hacks

Earlier this year we covered a study on REM sleep behaviour disorder (RBD) where normal sleep paralysis breaks down and sleepers act out their dreams. The Journal of Forensic Science has just published a study on the dark side of the disorder, where affected sleepers experience nightmares and can unknowingly damage themselves or their partners in fits of dream world violence.

The researchers examined all the published cases on violence in REM sleep behaviour disorder with potential for a lethal outcome and found they fall into three groups: choking or headlock attacks, throwing someone or throwing yourself through a window, and diving from the bed.

Some of the descriptions are pretty intense:

A 63-year-old man with RBD and delayed-onset Shy-Drager Syndrome reported “a progressive 10-year history of abnormal behavior during sleep. He would at various times choke, kick, punch, and spit on his wife while he was asleep. In addition, complex behaviors such as getting out of bed and running into walls while asleep were reported by family members. This behavior occurred while the patient was dreaming, usually of being attacked.

A 67-year-old man had a 3-year history of progressive stiffness and slowing of his left side. Five years before the onset of these symptoms, he began having vivid dreams together with violent movements during sleep. Once he dreamed of being trapped in a house on fire, and he almost jumped out of the window, if not for his wife awakening and restraining him.

A 25-year-old woman with multiple sclerosis “presented with a 6-month history of sudden awakenings from fearful, often vivid‚Ķdreams and with terrified screams or violent behavior such as kicking, running to the door or to the window, crying and falling out of bed. If awakened, she always recalled a fighting dream. Once she repetitively banged her head against the floor, inducing a large facial hematoma. On that occasion, she was dreaming that a man was knocking her against the wall.

The idea that someone could be violent during sleep without any awareness was initially treated with suspicion but it has since been confirmed in sleep labs where patient are video-taped and wired up to an EEG to confirm they are in REM sleep.

There have now been numerous legal cases where ‘sleepwalking violence’ has been used as a defence for murders or attempted murders, and at least one case where it led to a successful acquittal.

Link to summary of RBD lethal violence study.

One of the most influential and controversial papers in psychiatry was from a 1976 study published in The Lancet that found that people with schizophrenia had larger fluid filled ventricles in the brain.

Yesterday, I looked up the original paper in London’s Institute of Psychiatry library and was amazed to see that the controversy seems ingrained into the paper copy, which has been ripped, repaired, damaged and defaced.

In the early days of scientific psychiatry, during the 1800s, many famous German psychiatrists expended a great deal of effort examining the post-mortem brains of patients with schizophrenia (also known at that time as dementia praecox) attempting to demonstrate Wilhelm Griesinger’s theory that “all mental illness is disease of the brain.”

Despite numerous studies, they were unable to replicate the success of studies on dementia, which they linked to specific changes in the brain. So for generations, schizophrenia came to be defined as a condition in which the brain was structurally normal.

This fact was often highlighted by the antipsychiatry movement to suggest that ‘mental illness’ was nothing more than a difference in human experience and there was no medical evidence supporting the work of psychiatrists.

But the fact was also cited by many psychiatrists resistant to the relatively new wave of medications that had appeared on the scene. The drugs were claimed to ‘fix’ the brain with the assumption that the discovery of clear evidence for brain differences would just be a matter of time.

Enter Eve Johnstone and her colleagues at Northwick Park Hospital in London, who, in the midst of this politically charged environment, completed a study that compared CAT brain scans of 18 patients with schizophrenia to a group of healthy control participants. Alongside the scans, the researchers also tested the participants’ mental abilities with psychological tests.

The results were striking. They found the size of the ventricles, the fluid filled spaces in the brain, was, on average, larger in patients with schizophrenia and that it was correlated with the degree of difficulty with tests of memory, concentration and problem solving.

This caused enormous interest and controversy at the time. The paper copy from London’s Institute of Psychiatry library clearly reflects this, as it has been read so many times (and possibly ripped out) that it is virtually in tatters and has been reattached with sticky tape in an otherwise pristine copy of the journal.

There are a few annotations on the page, including the word “Rubbish” written in the margin!

Although seminal, the study has been rightly criticised and one of the major difficulties with these sorts of studies is that because patients are normally taking antipsychotic medication, it’s hard to distinguish where the effect is linked to schizophrenia or the treatment.

While some medication is thought to also thought to affect brain structure, a study on patients that have never taken medication seem to suggest some differences in ventricle size, on average, are still apparent.

The ‘on average’ bit is important though, as these differences are not present in everyone with the diagnosis. They’re just an average difference when you compare a group of people with and without schizophrenia. Furthermore, we’re still not quite sure of its significance.

So the topic is still as controversial as when Johnstone’s study first appeared in 1976, although the argument has shifted from whether differences in the structure of the brain are associated with schizophrenia, to whether they are telling us anything useful.

Link to scan of article from Institute of Psychiatry library.
Link to PubMed entry for same.

A fascinating study just published in the medical journal Pain examined the side-effects reported by patients taking placebos in clinical trials to test migraine drugs. It found that side-effects from placebo were almost as common as from the actual drug, but most interestingly, were specific to side-effects you would expected from the comparison medication.

In other words, the side-effects you get from a sugar pill in a study on anticonvulsant drugs closely resemble side-effects you get from anticonvulsants and are different from the side-effects you get from a sugar pill in a study on pain killers, which more closely resemble pain killer side-effects.

The researchers, led by neuroscientist Martina Amanzio, looked at trials for three type of migraine drugs: NSAIDs (like aspirin), triptans that work on the serotonin system, and anticonvulsant drugs more often used to treat epilepsy.

Side-effects from placebo are known as the nocebo effect and just the combined list of side-effects from the placebo groups in this study is surprising enough:

abdominal pain, anorexia or/and weight loss, attention difficulties, burning or/and flushing, chest discomfort, chills, diarrhea, dizziness, dry mouth, dyspepsia, fatigue, heaviness, injection side reaction, insomnia, language difficulties, memory difficulties, nasal signs and symptoms, nausea, numbness, paresthesia or/and tingling, pharyngitis, somnolence or/and drowsiness, stinging or/and pressure sensation, taste disturbance, tinnitus, upper respiratory tract infection, vomiting, weakness

It turns out that when placebo was being compared to an anticonvulsant, side-effects more common in these drugs – like fatigue, reduced appetite, sleepiness and tingling sensations – were more common in the placebo. In contrast, stomach upsets and dry mouth were more common in the placebo group when the comparison was with NSAID painkillers, which more often cause these symptoms themselves.

One explanation may be that before taking part in a clinical trial, patients are informed of the possible side-effects that the active drug may cause, regardless of whether they are going to be given placebo or the actual medication.

Information on the possible side-effects will be specific to the real medication, and, as we know that expectation plays a big part in the placebo effect, it is probably also shaping the nocebo effect and leading to the production of symptoms through expectancy.

Link to PubMed entry for study.