A man strangles his wife while dreaming about fighting off intruders in his sleep. Does that make him mad, bad or innocent? Recent research is helping to unpick these issues, and may help reveal who, if anyone, bears responsibility in such cases.
Last week, British man Brian Thomas appeared in court on a murder charge after strangling his wife as they slept in their camper van. The prosecution withdrew the charges after three psychiatrists testified that locking him up would serve no useful purpose. The judge said that Thomas bore no responsibility for his actions.
The case has cast a spotlight on the use of such sleepwalking defences in court. "If you look at the media reports there appears to be an upsurge in the use of the sleepwalking defence," says Michel Cramer-Bornemann of the Minnesota Regional Sleep Disorders Center in Minneapolis.
Thomas had a genuine sleep disorder, but Cramer-Bornemann is concerned that in many other cases, the sleepwalking and other sleep-related defences are misused. Studies on the causes of sleepwalking may eventually make it easier to identify who has a genuine sleep disorder that could occasionally result in violence, and who is making it up.
Lucid dreamers
Last month, Ursula Voss of Bonn University in Germany and colleagues reported that even during lucid dreaming – a state in which some people claim to be able to control their dreams – some areas of the brain associated with intent stayed offline, while other areas associated with consciousness were active. "As long as you are in a dream, you have no free rein on your actions and emotions," says Voss (Sleep, vol 32, p 1191).
Although this research didn't look specifically at sleepwalkers, it tallies with a previous study by Claudio Bassetti at the University of Zurich in Switzerland, who once managed to manoeuvre a sleepwalker into a brain scanner during a sleepwalking episode. He found the sleepwalker also showed no activation in the areas of the brain associated with intent, though emotional areas and those associated with movement were active (The Lancet, DOI: 10.1016/S0140-6736(00)02561-7).
"Our judgement is off and our ability to act out emotionally is on," says Rosalind Cartwright of the Sleep Disorder Service and Research Center in Chicago. She believes a confirmed diagnosis of sleepwalking would make a strong defence in court, but says better tests are needed to establish who has a genuine sleep disorder.
Sparking sleepwalking
That might become easier with the recent discovery that auditory stimuli, such as a dog barking, can trigger sleepwalking in those susceptible to it – particularly if they have been suffering from sleep deprivation. Antonio Zadra at the University of Montreal in Quebec, Canada, and his colleagues measured the brain activity of 10 sleepwalkers and 10 control subjects to determine what stage of sleep they were in.
They found that sounding a buzzer during "slow wave" sleep triggered sleepwalking in three of the sleepwalkers under normal circumstances, and all 10 sleepwalkers when they had been kept awake for 25 hours prior to sleeping. None of the control subjects were prompted to sleepwalk when the buzzer was sounded (Neurology, vol 70, p 2284).
The study might eventually enable a test for genuine sleepwalkers. "That's a big breakthrough," says Cartwright. Until recently, defence lawyers used evidence of sleepwalking in childhood or a family history of the activity to back up their claims.
However, Zadra cautions that other factors, like having the motivation to commit a crime, must also be taken into account. "We should not forget that some sleepwalkers can be criminals," he says.
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Have your say
The couple were good friends of my Girlfriends family. The couple were very close indeed and he was never aggressive towards her
SHAME ON NS
~~~~~~~~~~~~
This has been reviewed by legal and scientific experts without input from the tabloid NS and its readers.
The family has suffered enough. Shame on NS.
People, don't renew your subscriptions.
Hang on - NS confirm that he had a legitimate condition, how is that adversely affecting the family in any way beyond simply mentioning it?
From the point of view of somebody who sleeps normally, I'm a bit skeptical about such things. But in any case, shouldn't a person who can't stop themselves from committing crimes - and who are likely to be committing them again - be locked up as criminally insane? Nothing's to stop this guy from strangling his next wife in her sleep, too.
No just handcuff to the bed
I don't know how likely it is to happen again. But it would be prudent if he sleeps alone from now on, and maybe locks himself in. I can't really imagine he would want to run the risk himself, either.
"I'm a bit skeptical about such things."
You are alone in the house. Your wife has gone on a trip but comes back early for whatever reason, has lost her keys and phone but forces her way into the house in her own tried and trusted way, she doesn't want to wake anybody.
You run downstairs thinking it is a burglar (and if this is the US) shoot her.
You are a sane man, in a loving relationship, no history of violence.
It's not murder. It's not even manslaughter. It is a tragic accident.
Or, you are in a car, you have perfect mental and physical health, your car is serviced regularly, you are not tired or intoxicated. You suddenly veer off and mow down some pedestrians.
You had a sudden muscle spasm. Seems trite.
For the car, I actually heard of a case where some people were injured because a driver sneezed at the wrong moment, just to go ploughing into a line of cars.
"From the point of view of somebody who sleeps normally, I'm a bit skeptical about such things."
That's right buddy, if it doesn't happen to you it's obviously made up. I don't believe in cancer either because I've never had it.
Likely To Happen Again?
Tue Nov 24 17:26:34 GMT 2009 by Tony Coleby
http://perfectyellow.co.uk/
Though this is a tragedy, the question must be asked, what if it happens again? What could we do to stop it happening again?
We could lock him up for murder, that would stop it from happening again.
I guess if I were in that unfortunate man's position, I would sleep alone from now on, behind a locked door.
That's standard operating procedure for werewolves.
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