Pubdate: Sat, 21 Jun 2014
Source: New York Times (NY)
Copyright: 2014 The New York Times Company
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Website: http://www.nytimes.com/
Details: http://www.mapinc.org/media/298
Author: T. M. Luhrmann

CANDY'S DANDY, BUT POT'S SCARY

As Marijuana Laws Ease, the Risks Grow

WE know that occasionally people react badly to marijuana. Some 
withdraw into anxious, glassy silence. Some responses are more 
horrifying. In a recent, much discussed case, a Denver man bought 
cannabis-infused Karma Kandy and hours later - perhaps after also 
taking prescription pain medication - began raving about the end of 
the world and killed his wife.

Marijuana is more dangerous than many of us once thought. For one 
thing, cannabis use is associated with schizophrenia, an often 
devastating disorder in which people can hear disembodied voices that 
sneer, hiss and command. A 1987 study published in The Lancet, the 
London-based medical journal, followed more than 45,000 Swedish 
military conscripts. Those who said on a conscription questionnaire 
that they had used cannabis more than 50 times were six times as 
likely, 15 years later, to have been diagnosed with schizophrenia 
than those who said they had not used it. There have been many more 
research papers since. A 2007 meta-study, also published in The 
Lancet, examined a series of them and concluded that there was a 
consistent increase in the incidence of psychosis - the radical 
disconnect from reality characteristic of schizophrenia - among 
people who smoked marijuana, with most studies showing a 50 to 200 
percent increased risk among the heaviest users.

The causal arrow is complicated here. This does not prove that 
marijuana brings on schizophrenia. It could be that people with 
incipient schizophrenia are drawn to cannabis. But it is clear that 
cannabis can lead to passing paranoid and hallucinatory experiences, 
and a 2014 psychiatric overview argued that cannabis could not only 
cause those symptoms to persist, but to develop into a condition that 
looks like schizophrenia. Jim van Os, a leading European 
schizophrenia researcher, suggested that marijuana might be 
responsible for as many as one in seven or eight cases of 
schizophrenia in the Netherlands.

To be sure, that increased risk is pretty low: About one in 100 
people will develop schizophrenia. The unnerving question is whether 
in this country, with its history of gun violence and its easy access 
to guns, a person with a paranoid reaction is more likely to act violently.

A basic anthropological insight about drugs and alcohol is that the 
effect of a drug is a result not just of biology, but also of 
culture. The classic argument on this is "Drunken Comportment," a 
1969 book in which Craig MacAndrew and Robert B. Edgerton said that 
the effects of alcohol depended on local expectations. They wrote 
that when Americans drank, they fought, argued and were much more 
relaxed about sex.

When American undergraduates get drunk, they throw sofas out of the 
frat house and wake up next to people they didn't think they knew. 
That's because we Americans think that alcohol is disinhibiting and 
that we can't really control what we do.

That's not necessarily the case in other cultures. Mr. MacAndrew and 
Mr. Edgerton gave example after example of people in other cultures 
who drank plenty of strong alcohol but didn't behave as Americans did 
when drunk. In these societies drunks became silent, "thick-lipped," 
or they grew talkative, but not violent. In some settings, the 
anthropologists were able to demonstrate that when drunk, people 
became violent in culturally rulebound ways.

When Mr. Edgerton was doing fieldwork in Kenya in 1962, for example, 
he was warned about a man who became dangerous when drunk. But when 
he encountered that man during a drunken episode, "the man calmed 
down, and as he walked slowly past me, he greeted me in polite, even 
deferential terms, before he turned and dashed away." The drunk role 
did not include being violent to visiting anthropologists.

How people act when drunk, these anthropologists argue, is a learned 
behavior. People learn what it is to be drunk and what drunkenness permits.

Since then, anthropologists have demonstrated that this principle 
applies - to some degree - to the experience of many different drugs. 
As Eugene Raikhel of the University of Chicago summarizes the 
literature, drug experience is determined not only by the body's 
chemistry but also by local ideas about what those drugs should do.

Right now, for many people, marijuana conjures up the mellow calm of 
the Rocky Mountain high. But that mellowness is associated with a set 
of cultural cues that may not be shared by all who buy legal 
cannabis. Alcohol is a factor in about 40 percent of violent crimes, 
according to surveys of perpetrators. Let's hope that the meaning of 
being high doesn't migrate.
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MAP posted-by: Jay Bergstrom