Ed Andrieski / AP

ASPEN, Colo — If you ask certain pot aficionados here, marijuana is “not a drug.” It certainly isn’t sold like one, now that pot legalization has swept through these spruce-dotted valleys like smoke through the neck of a gravity bong.

The tiny downtown area of this resort city, population 6,700, is home to six street-facing, bonafide pot shops. A gondola that ferries skiers up and down Aspen Mountain is referred to, lovingly, as the “ganjala.”

The pot-vending operation here is aggressively—almost desperately—respectable, like a teenager making conversation with his great-aunt. “Budtenders” talk of “educating consumers” even as they misuse words like “implement” and “stigma.”

A Harvard neurobiology lab this is not, in other words. But it’s civilized. Pot sellers’ golfball-sized green nuggets smell fresh and pungent, like hot peppermint tea. They’re neatly organized in mason jars with labels like Kandy Skunk and Turbo Diesel. Customers emerge toting branded shopping bags, pre-emptively grinning. Everyone has their ID’s checked—even reporters who are just in there for quotes.

Here’s the hookup: You walk into one of these stores, which are named “Silverpeak” and other un-edgy things that won’t scare off your grandma. You give them some money. They give you pot.

You don’t have to winkingly tell a “doctor” that you get terrible backaches nothing else will cure. You don’t have to know a guy. You can just buy it, as banally as you buy toilet paper or a Diet Coke.

It’s so easy it’s boring.

But is it boring enough? As in, are you still worried you’re doing something wrong?

The vibe of marijuana—the smoke! the rebelliousness! the lingo!—can be exciting. But when it gets too exciting, the dreadful dark side sets in: the paranoia.

One minute you’re sitting there, enjoying the Discovery channel or simply the awesome shape of your own hand. The next, you ardently believe your eyeballs might liquefy and drain out of your face. Or, more realistically, that the police will find you, using their patented stoner-radar, and bust you. No matter if a person can’t be jailed just for being high. When the paranoia strikes, you find yourself pleading with the intoxication gods to free you from your baked prison.

But what if there are no cops? Because what if there is no law saying you can’t possess or smoke or sell or buy marijuana?

Recreational marijuana isn’t legal for most Americans. But it soon might be, thanks to initiatives on the ballot in several states this year. I was curious whether a laxer legal environment afforded pot-smoking citizens a freedom from pot-induced paranoia, as well. I took to the mean streets of Aspen to find out.

My first problem was making sure my sources understood what I meant by “paranoia.”

At a store called Roots Rx, budtender Alex Reyes told me that whether tourists feel nervous depends on the social norms of their homelands. “A lot of Texans, they're like, can I come in?” he said, imitating a tentative southerner. “You know, their weed laws are so strict I can't even imagine.” (Actually, even Texas has legalized medical marijuana for epileptic people, but perhaps the state’s reputation for not being messed-with precedes it.)

At the Green Dragon, on one of Aspen’s busiest streets, a man named Emery Long strolled in for a pack of Zig Zag rolling papers. He’s lived here for about a year, but he visited periodically before marijuana was legalized. Medical marijuana was approved in the state more than a decade ago, and recreational sales began in 2014.

Long said paranoia is worse under the new regime, since now people have to worry about their credit-card statements revealing a pot purchase, or having their pictures taken near one of the stores and posted on social media for the scornful eye of their employers. “Now everyone sees you because you come into a public place instead of going to your caregiver's house,” he explained.

But, that’s not the kind of generalized angst—Oh man, my boss knows I smoke weed—that I’m curious about. I was wondering about the all-consuming, irrational dread that seems to strike marijuana novices, in particular, when they’re high. After all, the people who would probably suffer the worst paranoia ​are​ the first timers and the tourists, especially those who listened raptly in their 5th grade D.A.R.E. classes and forgot to update their worldview with age. Or at least that’s my theory.

The few scientists who study pot-induced paranoia generally concur that whether a pot user gets paranoid depends on her tolerance and just how much marijuana she’s consumed. There also might be a genetic component, according to Steven Laviolette, who has studied the neurobiology of pot at the University of Western Ontario in Canada. He’s found that the psychoactive compounds in marijuana increase the synaptic connections between the amygdala, the brain’s fear center, and the prefrontal cortex, which processes responses to stimuli. As a result, the brain might twist innocuous information, filing sights and sounds under “scary” when they’re actually quite normal. People with heightened anxiety—especially those who know they’re doing something illegal—might be likelier to get paranoid.

Another theory is that paranoia arises from a mismatch between a pot smoker’s expectations and how high he actually became. Deepak Cyril D’Souza, a professor of psychiatry at Yale University School of Medicine, recalled a time in the 1990s when he gave a lab subject THC intravenously for a marijuana study. The man at first felt happy and euphoric, but he gradually grew progressively quieter. He asked the researchers if they were still dripping THC through his IV lines, and D’Souza answered (truthfully) that he wasn’t. Nevertheless, the man asked D’Souza to remove first his IV lines, then his blood pressure cuff, and finally his bed sheets.

Because people get so paranoid even in clinical, supervised environments, D’Souza told me, he doesn’t think legal status would affect the phenomenon.

Max Meredith, the manager of the Stash marijuana store in Aspen (Olga Khazan / The Atlantic)

The Aspeners seemed mixed on whether this kind of paranoia has abated since legalization, or even if the two are related. The Aspen police said they’ve seen a slight increase in ambulance calls from people who eat too many edibles and start hyperventilating. But the rise is negligible: One call every two or three months these days, compared to none before legalization.

Around town, paranoia seemed more like a personal issue than a legal one. At a restaurant called the Red Onion, Jeff Kromschroeder was enjoying a beer for his 44th birthday. He said he wished he was getting stoned instead, though. He only sometimes gets paranoid, but he considers it part of the rush.

A few barstools down, a short, thin brunette named Carina McCormick said she would sometimes get paranoid, back when she was underaged and pot was illegal. She and her friends would smoke behind dumpsters to avoid being seen. “Now that I’m 24 and it's legal, I don't feel as scared about it,” she said.

Further down the road, a man who would only give his name as Trevor said his wife found paranoia to be worse in Colorado. They’re from Missouri, and she says the weed is too strong down here. A friend who was walking with Trevor said she still gets paranoid, but only when she eats marijuana-infused edibles. “They make me think my head's going to fall off,” said the woman, who asked to go by only her first name, Michelle, because of job concerns.

But legalization, they agreed, had little to do with it.

Indeed, it likely has more to do with the relative proportions of cannabidiol to THC, two psychoactive compounds, in any given strain. The two chemicals work in opposite ways, with high concentrations of THC prompting delusional thoughts and CBD dampening them. Sagnik Bhattacharyya, a neuroscientist at King’s College in London, found that THC seems to ramp up the brain’s response to unremarkable stimuli.

Let’s say you smoke pot and go for a bus ride. Every day on the bus, other passengers look around, talk to each other, and laugh. It’s so predictable you typically don’t even notice it. But to your blazed brain, these normal conversations might actually be about you. Or worse yet, your fellow passengers might be plotting your demise.

This connection between THC and delusions is why the Aspen budtenders try to steer customers who are concerned about paranoia toward the lower-THC indica strains. They also caution those buying edibles to start with a tiny nibble and wait three hours before eating more.

If legalization has played a role in easing paranoia, it’s that. It ushered in a formal customer-service system, complete with advising and recommending, so that even the most repressed of Texans aren’t afraid to ask what Lemon Kush will do to them.

Because pot is, in fact, a drug. As with other drugs, people are drawn to it and, occasionally, frightened by its powers. The budtenders might entertain some far-fetched notions—one store hawked a dubious “rescue tonic” of sugar and cherry powder—but they’re adequate captains for a maiden marijuana voyage.

At the very least, pot users here don’t have to worry about using code words and other sketchy tactics. Alec Orr, manager of the Native Roots dispensary, told me that after he moved here from his native Georgia, he found it freeing to call the glass pipes in the store by their true name, bongs.

In Georgia, he explained, saying “bong” in a head shop could get a person thrown out. The saying was, “if it rhymes with song, it’s wrong.” Talk about paranoia.

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