Researchers Find the 1st Possible Negative Side Effect of Marijuana Use in Adults

Brain blood flow in those with cannabis use disorder was found to be significantly restricted. 

 

The stigma against marijuana in the US has been eroding for decades. But over the last ten years, use has skyrocketed. Since 2002, the number of Americans using the drug has almost doubled, according to a recent survey. In 2001, 4.1% said they had smoked marijuana within the past year. By 2014, 9.5% had done so. The number of patients using it to control the symptoms of an illness or disorder has risen substantially as well. Since it has been found far less dangerous that alcohol and other intoxicants, cannabis is quickly becoming the drug of choice for many Americans. New laws have allowed for medical marijuana in over half the states and recreational marijuana in about a half dozen.


Cannabis is also the most commonly used illicit drug in the world, according to the WHO. While opponents to liberalization often talk about it as a gateway drug, there is little evidence of this. In fact, scant data exists alleging that marijuana causes any damage whatsoever, if used in moderation, once the brain has stopped developing. But for chronic users, a new study imposes a harsh warning.

Researchers at Amen Clinics Inc. of California have found evidence that chronic use may increase the risk of Alzheimer’s. This is because it restricts blood flow to the regions of the brain where the condition takes root. Co-author Dr. Elisabeth Jorandby and colleagues recruited participants with marijuana use disorder. Around nine percent of users get addicted to cannabis. That’s a relatively low number.

Cannabis or marijuana use disorder is defined as using the drug chronically, even when it is clearly causing significant cognitive impairment. The symptoms may be mild, moderate, or severe, depending on the particular case. Chronic use is considered daily or near daily use. Those who habitually consume are more susceptible to psychiatric disorders.  

Medical marijuana is available in 28 states in the US today. Seven states now allow the recreational kind, and many more cities across the nation have decriminalized pot.

In this study, published in the Journal of Alzheimer’s Disease, 982 current or former chronic users and 92 healthy controls underwent brain scans to evaluate blood flow there. Those diagnosed with cannabis use disorder showed a significant reduction in brain blood flow in almost every region. The hippocampus, which is where Alzheimer’s originates, saw the largest reduction. This is the area responsible for learning and memory.

Few previous studies have evaluated blood flow inside the brain as an effect of chronic marijuana use, researcher’s said. This was measured using single photon emission computed tomography (SPECT). Participants had their brains scanned while performing a task and while at rest. Reduced brain blood flow would cause less oxygen to travel to neurons, which could lead to tissue damage.

Blood flow was especially restricted in the right hippocampus. Researchers believe marijuana may affect memory formation due to this effect. The study suggests consistent marijuana use causes damage to the brain. Possible effects include memory formation disruption. Other studies have suggested that restricted blood flow to the hippocampus can increase the risk of Alzheimer’s.

More research will have to be conducted to corroborate this claim. But it’s reasonable that someone who only lights up occasionally won’t have such an issue. This study conflicts with a 2014 preclinical trial, also published in the Journal of Alzheimer’s Disease. There, tiny doses of marijuana’s active ingredient, delta 9-tetrahydrocannabinol (THC) had neuroprotective qualities. It helped ward off Alzheimer’s by destroying beta amyloid proteins which are what cause the disease. So in the end, it may be an issue of dosage. A little is okay, but too much is damaging. But only more studies can tell us for sure.

To learn how marijuana affects memory in the short-term, click here: 

Steven Mnuchin withdraws from Saudi conference over missing journalist

Treasury Secretary Steven Mnuchin has cancelled an upcoming trip to an economic conference in Saudi Arabia amid the controversy involving missing journalist Jamal Khashoggi.

(Photo by Chip Somodevilla/Getty Images)
Politics & Current Affairs
  • Saudi Arabia's economic conference has been dubbed "Davos in the Desert".
  • Mnuchin joins a growing list of officials and industry executives who've dropped out of the event.
  • It's turning into a PR nightmare for the nation, particularly for Crown Prince Mohammed bin Salman.
Keep reading Show less

Where the water wars of the future will be fought

A new report warns about the increasing likelihood of international conflicts over water.

Abd al-Ibrahim, whose home was destroyed during fighting, as he rests on his trip to supply water to his family at the house they are squatting in the northern Syrian city of Raqa. October 15, 2018. (Photo credit: DELIL SOULEIMAN/AFP/Getty Images)
Politics & Current Affairs
  • A study finds that serious conflicts over water are going to arise around the globe.
  • The 5 hotspots identified by the paper include areas of the Nile, Ganges-Brahmaputra, Indus, Tigris-Euphrates, and Colorado rivers.
  • It's still possible to change course if we are prepared to address the effects of climate change.
Keep reading Show less
A Star Is Born, Warner Bros Pictures
Surprising Science
  • It has to do with two parts of the brain, both of which are thicker in those with better smell and spacial recognition.
  • Your nose can detect about 1 trillion smells.
  • While your nose isn't a full GPS, it can help you pick out a general direction.
Keep reading Show less
(Opener)
Technology & Innovation
  • A Larry Page-backed company has announced that its flying car will go on sale in 2019.
  • It's called the BlackFly.
  • Not quite the escape from traffic you had in mind, but it's a jaw-dropping start.
Keep reading Show less

The original 'Big Bird' puppeteer is leaving Sesame Street

He was recruited by Jim Henson himself in 1969.

(Photo by Slaven Vlasic/Getty Images for HBO)
Culture & Religion
  • His last performance will be this coming Thursday, Oct. 19
  • A feature movie about him was made in 2014
  • Other actors will take over. Well, at least, they'll try ...
Keep reading Show less

Being busy all the time is a habit you made. You can unmake it.

There will never be enough time. Here's how to use it more wisely.

Videos
  • One-third of us are suffering from chronic stress in the workplace. Other studies suggest that half of us bring our work stress home, creating stress in our personal lives.
  • Being busy has become a cultural obsession. But it's not the golden badge of honor we think it is. Dan Pontefract points out that there's a big difference between being busy and being productive.
  • The best productivity hack? Schedule a break. That means eating lunch away from your desk. Saying hello to people around you. Keep a graph in your mind that has 'action' on the x-axis and 'reflection' on the y-axis. Where do you sit on that graph?

7 brilliant Japanese words we need in English

Ever wanted to describe precisely how crummy you feel after a bad haircut?

Culture & Religion
  • English is a phenomenal language, but there are circumstances where words seem to fail us.
  • Often, other languages have already found a solution to expressing the complicated ideas that can't be succinctly conveyed in English.
  • If you've ever wanted to describe the anguish of a bad haircut, the pleasure of walking in the woods, or the satisfaction of finding your life's purpose, read on.

Don't get me wrong. The English language has some very excellent words. There's petrichor, the pleasant smell of the first rain after warm and dry weather. Paraprosdokian—which describes sentences that end surprisingly, forcing the reader to reinterpret the first half—is both oddly specific and fantastic to say out loud. I'm even a fan of new inventions, like tweetstorm, even if I'm not a fan of the experience.

But English-speaking culture—like any culture—has a limited perspective on the world. Just like English, Japanese also has some five-star words that English could stand to borrow. The Japanese have an entirely different perspective on the world than many English-speaking cultures—as proof, it's tough to imagine that the politely reserved Japanese have a word for defenestrate, or the act of throwing somebody out of a window. Here's the top 7 Japanese words that we could use in English.

1. Ikigai

(Flickr user Raul Pacheco-Vega)

Literally translating to "life value," Ikigai is best understood as the reason somebody gets up in the morning—somebody's reason for living. It's a combination of what you are good at, what you get paid to do, what you love to do, and what the world needs.

We often find our ikigai during flow states, which occur when a given task is just challenging and absorbing enough that we forget time has passed, that "in the zone" sensation. But it's more nuanced than something that is simply absorbing or a passion; it's a fulfilling kind of work that benefits oneself and others.

2. Karoshi

Karoshi, or death from overwork, provides a nice contrast to the concept of ikigai. Japan's work culture is so over the top that dying from working too hard is not uncommon. This word covers a range of ailments from heart failure to suicide, so long as the root of their cause is in working too hard.

As another hardworking nation, the U.S. could stand to better appreciate the dangers of overwork. Americans put in an average 47 hours a week, which is demonstrably bad for our health.

3. Shinrin-yoku

(Flickr user jungle_group)

This word translates to "forest-bathing," which sums up the activity fairly well. It's getting outdoors to de-stress, relax, and promote well-being. While the concept is familiar, we clearly don't place enough importance on getting outdoors to honor it with its own term.

According to the Environmental Protection Agency, Americans spend about 87% of their time indoors, which is clearly too much. Meanwhile, being in nature is associated with a slew of benefits, like improving memory, reducing stress and anxiety, and even lowering inflammation. Scotland has the right idea—doctors in Shetland can now prescribe nature to their patients.

4. Shikata ga nai

Used interchangeably with shouganai, this term roughly means "it cannot be helped." You can think of it as the Japanese equivalent of c'est la vie´or amor fati. It's the idea that one should accept things outside of one's control with dignity and grace and not implode from the pressure of having no control over a terrible situation.

This concept is a bit controversial. During the U.S. internment of Japanese-Americans after the bombing of Pearl Harbor, many Japanese-Americans resigned themselves to their mistreatment, characterizing the situation as shikata ga nai.

On the other hand, when a tsunami devastated Japan in 2011, many outside observers commented upon the stoic way the Japanese carried on with their daily lives, an example of the positive side of shikata ga nai.

5. Tsundoku

(pexels.com)

While it's a little less high-minded than the previous words on this list, it's certainly one that I and others could use. A combination of tsunde-oku (letting things pile up) and dukosho (reading books), tsundoku is the practice of buying a book you swear you're going to read, obviously not doing that, finding a new book you swear you're going to read, and then letting these abandoned books pile up in your house until it's a certifiable fire hazard.

6. Irusu

Garden State (2004)

You're in a terrible, anti-social mood and don't want to see anybody at all today. Suddenly, your doorbell rings; you lie as still as possible in your bed (surrounded by the hordes of unread books you purchased), praying the unwanted visitor leaves. This is the practice of irusu, or pretending not to be home when somebody rings your doorbell. It's a very common experience, although maybe the modern-day equivalent is responding "Sorry, I just got this" hours after you actually saw a text.

7. Age-otori

Not everybody practices tsundoku, and I'm sure some extroverts are entirely unfamiliar with practicing irusu, but everybody can identify with getting a bad haircut. Age-otori is the feeling one gets after leaving a barbershop looking worse than you did going in. It's an ingenious word for the unique blend of regret, suffering, and shame you feel after you foolishly trusted your elderly barber when he said "Yeah, I can do a hard part."

Bonus words

While Japanese has some phenomenal words, there are some that the English language probably doesn't have need of. For example, a nito-onna is a woman so obsessed with her job that she doesn't have time to iron her blouses and so resorts to wearing knitted tops constantly. It's a wonderfully specific word, but its specificity probably doesn't translate to English-speaking contexts.

There's also the hikikomori, a mostly Japanese phenomenon involving modern-day hermits that don't leave their bedrooms for years and years. People like this exist in English-speaking contexts, but we generally characterize these as people suffering from anxiety, as loners, or hermits. In addition, part of what makes a hikikomori is the high pressure and highly ritualized nature of Japanese society, a feature that is mostly absent in English-speaking contexts.

So, write to our good friends Merriam and Webster. Let's see if we can pack a little more utility into the English language.

Earth used to be purple, new NASA study shows

NASA research finds a new direction in searching for signs of life in the Universe.

Surprising Science
  • NASA-funded research says retinal, not chlorophyll, gave the early Earth its color
  • The two pigments co-evolved but retinal came first
  • We should be looking for retinal-based life throughout the Universe
Keep reading Show less