Vermont is among more than 15 states and the District of Columbia that have legalized recreational cannabis. But broader social acceptance of the drug doesn't address the health and public safety concerns that come with more people using it. A new app developed by a St. Michael's College psychology professor could help.VPR’s Mitch Wertlieb spoke with St. Michael’s professor Ari Kirshenbaum about the he's developed, which aims to help cannabis users gain awareness of how the drug is affecting them. Their conversation has been edited and condensed for clarity.
Mitch Wertlieb: Before we get into this app, I'd like to know why you are interested in studying marijuana in the first place. Because I understand that you have a personal connection to wanting to see responsible cannabis use.

It would be disingenuous to say that my interest in the app really came from my experience with cancer. My partners and I had already been working on the app prior to that, because both of my partners are involved with public health and public safety in various ways. But my cancer diagnosis really changed the emphasis of where we were going with the app.
My real goal with the app is to just collect information about how cannabis and THC alter neuropsychological functioning. And really, my overarching goal, as both a professor and as a scientist, is to provide the public with information. Because a better informed society is a better society, in my opinion.
You and your colleagues used a National Science Foundation grant to develop this app to measure “neurocognitive aptitudes,� things like reaction time, concentration, time perception. And you do this through what you call, essentially, “brain games.� How do those games work within the app you've developed?

We designed these games based upon 40 years or so of laboratory research, in which psychopharmacologists give controlled doses of cannabinoids [like THC] to various participants in the laboratory. And what we've tried to do is take all of that data and distill it into what we call a “rapid neurocognitive testing procedure.� So there are a variety of different tests, and each one taps into just a slightly different neuropsychological domain.
When you open the app and you start to, let's say, play one of these games, you know, there are so many different kinds of games you can get on an app. This is not something like Angry Birds. This is testing something different. How exactly would it work for the user?
Take, for instance, [people who] use our app when they're sober. The app then accumulates that data and shows it to that user, on how they perform under these baseline conditions. And then if they were to use a little bit of cannabis for whatever reason, the app would give their performance relative to their sober performance.
All of us understand at some level how alcohol impairs our ability to function. And we all have some sort of understanding that, well, let's say, we can have a beer an hour. As long as we keep to that, we're not necessarily going to be intoxicated.
"I think the important conversations now need to become: what is a safe dosage? What are the levels at which you can use cannabis and be safe to drive?" - Ari Kirshenbaum, professor at St. Michael's College
We don't have any such information like that about THC or cannabis. And I think that it's going to be very useful for users of cannabis to have that information. And I also think it's going to be very important for dispensaries, with the wave of legalization across the country, to be able to provide their clients with useful information about how their products are affecting them.
That dilemma you just mentioned � that we have ways of measuring alcohol and knowing when we're intoxicated � this is one of the big concerns that Gov. Phil Scott had about legalizing marijuana in Vermont. He was worried about things like people using marijuana and driving because there's no reliable kind of breathalyzer test [for cannabis] like you would have for alcohol. Is this something that you see this app being used for?

Well, potentially � maybe. I think we want to have more conversations with the law enforcement community. But I think our initial goal is to improve public safety by informing consumers themselves. And then eventually, if we get enough evidence, if we find that the app is really effective and it's accurate, then maybe we can pursue those other avenues.
But you're absolutely right. Saliva testing and breathalyzer testing for cannabis is scientifically unjustified, in my opinion, and they represent threats to civil liberties. And these are the reasons why [the state of] Vermont has not permitted the collection of oral solutions or blood or breathalyzer as a means for detecting cannabis at roadside.
Can you give me sort of like a real-world practical effect of this use? Does the app give you sort of a number, say, "You are this high," or that kind of thing? Or is it more like the user has to sort of gauge what they've done while sober [and] compare it to what the app says when they're high, and then make a determination about how high they actually are?At this point, the app cannot be used as a reliable tool to say whether or not you are safe to drive, or you're safe to operate heavy equipment. All the app does is it gives you some hopefully useful information about how cannabis is impairing you.
Some of the information that we're getting from the app has to do with the timing of the effect of the edible that you took; for example, [how many] milligrams you took.
You know, there are real problems with dispensaries, for instance. They market their vaping or smoke products in terms of percentage THC, but then the edible [cannabis products] are in milligrams. How is the average consumer supposed to make that leap from concentration, which is like ABV [alcohol by volume], to just a flat milligram?
You know, I'm a professor at St. Mike’s [College], so I think that, on my best days of being a professor, I probably am able to encourage productive conversation. I think that it's important to have productive conversations. And I think there are three types of conversations that are not productive with cannabis.
First and foremost, whether or not cannabis is dependence-producing; it absolutely is, there's a withdrawal syndrome associated with it. So, we need to have stop having that conversation.
Another conversation that we need to stop having is whether cannabis is effective for medical purposes. It absolutely is; it helps to relieve suffering for a wide variety of conditions, and that list of conditions is growing.
The third conversation that we need to stop having is whether or not you're safe to drive when you're stoned. You're not! You're impaired. And there are all sorts of indications from the National Highway Traffic Safety Administration, along with the [National] Governors Association, across the country, that it's not safe and it does increase your risk.
I think the important conversations now need to become: what is a safe dosage? What are the levels at which you can use cannabis and be safe to drive? And I think a really big question now, with dispensaries, is that we have so many different products � from tinctures to edibles to smoke products � and there's really no good standard to know when you might be safe to drive [or] when you might be better able to interact with your kids. And I think that kind of information is desperately needed.
If we can provide objective information to dispensaries about how their products are affecting their clientele, I think that that's going to be just a boon for public safety all around.
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