Conducting an economic analysis of drug use is a particularly difficult endeavor, but for Michigan State University professor and economist Siddharth Chandra, it just meant taking a look at the history books.
“You can’t simply go to Wal-Mart and look at the sticker price, and people don’t want to talk to you because drugs are illegal and they think they’ll get in trouble, ” Chandra said. “Our study is the first time the subject of how populations of consumers switch between drugs is being studied with data considered reliable.”
To find reliable economic data on drug use, Chandra, also the director of the Asian Studies Center at MSU, had to look back to early 20th century India, when the region was still part of the British Empire.
“One hundred years ago these products were legal. In British India the government was actually selling these things to the public, and they kept meticulous records,” Chandra said.
In his study – the first of its kind – Chandra pored through stacks of 100-year-old ledgers, called Excise Administration Reports, kept by the governments of the various provinces of India. Interpreting these data, he found surprising results about the economics of drug use behaviors. Despite the stark differences in the effects of opium vs. cannabis on the human body, the study shows that users would switch between the two drugs when the price of one went up – in economics, a phenomenon called substitution.
“The time, place and context are different, but the phenomenon is there. You might think consumers would treat them differently,” Chandra said. “But just because the two drugs used are very different, doesn’t mean people won’t switch.”
Opium, used legally to make the pain medicine morphine and illegally to make the drug heroin, is a highly addictive and potent depressant with potentially lethal side effects. Cannabis, also known as marijuana, is a less potent drug that produces a sense of relaxation and euphoria when used, usually through smoking or ingestion. These differences only came into consideration when analyzing cannabis in its weakest form, a drug called bhang, which consumers would not substitute for the more potent opium.
“There are many policy implications for these results,” Chandra said. “Targeting a particular drug with policies and enforcement might backfire.”
Chandra pointed to the epidemic of heroin, a product of opium that is relatively inexpensive and is devastating some communities in the United States.
“Many people know someone who has been affected by heroin – it is a very dangerous drug,” Chandra said. “But prohibiting harmful drugs selectively can be ineffective. Consumers may switch.”
Yogis may be enjoying a surprising benefit when they unroll their mats and strike a pose. A new study finds that just 20 minutes of hatha yoga stimulates brain function.
Researchers from the University of Illinois at Urbana-Champaign enlisted 30 subjects to take tests of working memory and inhibitory control, two measures of brain function associated with the ability to focus, retain, and use new information, the researchers said.
Subjects who took a single, 20-minute yoga session were significantly faster and more accurate on their tests than subjects who walked or jogged on a treadmill for 20 minutes.
Participants on the treadmill exercised with the goal of maintaining 60 to 70 percent of their maximum heart rate throughout the exercise session. “This range was chosen to replicate previous findings that have shown improved cognitive performance in response to this intensity,” the researchers said.
“Yoga is an ancient Indian science and way of life that includes not only physical movements and postures but also regulated breathing and meditation,” said study lead Neha Gothe. “The practice involves an active attentional or mindfulness component but its potential benefits have not been thoroughly explored.”
Subjects who practiced yoga performed a 20-minute sequence of seated, standing, and supine yoga postures, with the class ending in a meditative posture and deep breathing.
“It appears that following yoga practice, the participants were better able to focus their mental resources, process information quickly, more accurately and also learn, hold and update pieces of information more effectively than after performing an aerobic exercise bout,” Gothe said.
“The breathing and meditative exercises aim at calming the mind and body and keeping distracting thoughts away while you focus on your body, posture or breath,” she said. “Maybe these processes translate beyond yoga practice when you try to perform mental tasks or day-to-day activities.”
Findings, announced June 5, appear in the Journal of Physical Activity and Health.
A separate study published last month finds that twice-weekly yoga sessions can reduce high blood pressure. In the study, researchers led by Dr. Debbie Cohen of the University of Pennsylvania tracked 58 women and men, aged 38 to 62, for 24 weeks.
Another study published earlier this year in the journal Frontiers in Psychiatry found that the practice may soothe depression and help sleep problems.
New NIDA-funded research shows that heavy marijuana use (at least four times per week over the past six months) is linked to adverse changes in the function and structure of brain areas associated with reward, decision making, and motivation. Heavy marijuana use can also enhance some brain circuits – possibly to compensate for reduced function in specific brain regions. This effect was more pronounced in those who started using at a young age, indicating that developing brains are particularly vulnerable to marijuana’s effects.
Although further long-term studies are needed to determine whether marijuana caused these effects, these scientific findings add to the growing literature showing that heavy marijuana use may harm the brain.
For a copy of the abstract (published online November 10), go to www.pnas.org/content/early/2014/11/05/1415297111.abstract.
People who are exposed to secondhand marijuana smoke may feel a bit of the “high” that comes with using the drug, a new study finds. They may also feel unable to think clearly, and they may even have detectable levels of the drug in their urine or blood. But all of this happens only if they are exposed to marijuana smoke under severely unventilated conditions, the study found.
“If you’re going to breathe in enough passive cannabis smoke to feel high and potentially be slightly impaired, you could fail a drug test,” said Evan S. Herrmann, the study’s lead author and postdoctoral fellow in psychiatry and behavioral sciences at Johns Hopkins School of Medicine. “But this only happens under a very extreme situation.”
Cannabis is the world’s most commonly used illicit drug. It is often smoked in small, enclosed spaces with poor ventilation, according to the study.
Studies in the 1980s showed that such “social exposure” to pot smoke could trigger positive drug tests for cannabis’ main psychoactive ingredient, tetrahydrocannabinol (THC). But such studies had several limitations. They used marijuana that had much lower potency than the pot available today and they failed to account for normal levels of ventilation in rooms. They also did not examine how people may feel or behave after such exposures.
“This new study probes a question people have been wondering forever,” said Ziva Cooper, an assistant professor of clinical neurobiology at Columbia University, who was not involved in this research. “Do people actually get high from these ‘hot box’ effects? And if so, does it change your capabilities or cause you to fail a drug test?”
In the first study of its kind, Herrmann’s team recruited about 20 healthy people between the ages of 18 and 45, including some who smoked marijuana and some who didn’t use the drug. The researchers tested the participants’ blood, saliva, urine and hair samples for cannabis biomarkers, and then asked six smokers and six nonsmokers to relax in a Plexiglas and aluminum smoke chamber about the size of a dorm room. Participants underwent two separate sessions, each an hour long.
The researchers gave each of the six smokers 10 marijuana cigarettes, each containing 1 gram of high-potency weed, and instructed them to smoke at their leisure for the hour while the six non-smokers sat by their side in the chamber.
During one test session, the room’s ventilation system was switched on, allowing air to flow in and out at a standard office-building rate. In the other session, the researchers restricted the airflow in the chamber. After the 60 minutes, each participant completed a series of biological, cognitive and subjective surveys and tasks at regular intervals for up to 34 hours after exposure. [11 Odd Facts About Marijuana]
“Our results are pretty consistent with what we expected,” Herrmann said. The new findings confirm “it’s really hard to get a positive [drug test result] from passive smoke unless you’re in an extreme scenario,” he said.
Under the unventilated, “hot box” condition, the nonsmokers showed slight impairments on cognitive tests, reported feeling high, and had detectable levels of THC in their blood and urine for up to 22 hours post-exposure. Those in the ventilated condition had much lower levels of THC in their blood, did not feel impaired or high, and did not test positive for THC in their urine.
But the unventilated room is not representative of most real-life situations, the researchers said. “We modeled the worst-case scenario,” Herrmann said. “You are in an enclosed room for an hour with 15 grams of cannabis being smoked.”
Ideally, the study would have had a placebo group, in which nonsmokers were exposed to smoke without THC. This would have helped the researchers determine whether the feeling of being high was due to the marijuana or simply a placebo effect, from being exposed to smoke.
Still, “this study is really important because it adds to our limited knowledge of the direct effects of cannabis smoking and the potential dangers of second-hand smoke,” Cooper said.
History, despite its wrenching pain, cannot be unlived, however, if faced with courage, need not be lived again. Maya Angelou