The Science Behind Weed – How and Why does it get you High?
Have you ever looked at that spot on the wall before? No, really looked at it. If you love your weed, you’ve almost certainly been on one side or the other of a conversation like that at least once.
Perceiving the extraordinary in the mundane is one of the more intriguing effects of getting high. Of course, there are others, too, such as lack of inhibitions and that classic fall-back, laughing so long and uncontrollably that your jaw aches the next day.
How can it be that a simple little plant that first sprouted from the earth somewhere in the mountainous regions of Tibet can have such a profound impact on our senses and how we perceive reality? Most of us think we know the answer – it’s that mischievous cannabinoid THC messing with our minds.
The Endocannabinoid System
THC is one of more than 100 different cannabinoids present in cannabis, but the vast majority do not get you high. So what makes THC so different? To answer that, we first need to unravel the mysteries of the endocannabinoid system.
This is a relatively recent discovery and can best be pictured as a network of receptors that affect both physical and physiological functions such as pain, tiredness, concentration, anxiety, and so on.
The body naturally produces chemicals called endocannabinoids that trigger these different receptors and cause you to feel soreness when you bump your knee, anxiety when you are late for a meeting, or euphoria when you are reunited with a loved one.
When you ingest extra cannabinoids, they interact with those neurotransmitters to alter the message. The easiest way to think of it is like a dimmer switch.
This is why, for example, some people find that CBD helps to relieve pain or anxiety – it is not necessarily having any effect on the root cause – there’s still a bruise on your knee and the boss is still waiting for you in the conference room.
It simply modifies your neurological reaction meaning you don’t experience the same amount of pain or you feel less trepidation about arriving late.
How is THC Different?
When you ingest cannabis, and especially when you do so by smoking or vaping it, THC is rapidly absorbed into the bloodstream where it is a short journey to the brain and those receptors.
So far so good, and the same applies to CBD and THC. Where things become interesting is in the way the two cannabinoids interact with a specific receptor type known as CB1.
Without wishing to disappear too far down the rabbit hole, studies have shown that THC activates CB1 receptors, while CBD tends to repress it. Put simply, it seems that activating CB1 receptors turns up the volume of our emotions.
Studies are still in their infancy, but researchers have observed that different cannabinoids beyond just CBD and THC each have their own effect on those CB1 receptors. For example, synthetic cannabinoids like spice (K2) tend to trigger an extreme response, and this correlates with the potentially dangerous effects that these types of drugs can have.
THC, on the other hand, dials up the CB1 receptors more gently, while CBD dials them down. Now, we can begin to understand why different strains of cannabis can have such a range of effects.
In particular, it goes some way to explaining the more mellow kind of high that is engendered when you smoke a weed that contains a good blend of both THC and CBD.
Scrambling the Network
So much for CB1 receptors – but there is a whole lot more happening in the endocannabinoid system, and THC affects all of it according to pharmacological researcher Daniele Piomelli from the University of California.
He explains that THC arrives in the system “like a sledgehammer,” flooding it with signals that essentially scramble the usual flow of messages and information.
Until very recently, US regulations have made it very difficult to study the effects of THC, but according to the limited research his team has completed to date, he believes that it temporarily “unplugs” our brain from default thinking mode.
Ordinarily, we damp down the part of the brain that is concerned with daydreaming or pondering the past and future, so that we can concentrate on whatever we are doing.
With this “dampening field” switched off, all sorts of random thoughts are likely to invade our consciousness, and so it’s absolutely feasible that we will find ourselves completely distracted and entranced by a mark on the wall or the lines on our hands.
Piomelli stresses that there are still far more questions than answers when it comes to understanding exactly how THC works and what it really means to be “high,” but he says it is looking increasingly clear that its impact on the brain’s “default mode” is a major part of the equation.
He said that when the default mode network is switched off, it “takes us into a mental place where the function of the things we experience is less important than the things themselves: our hands are no longer just something we use for touching or grabbing, but something with inner existence and intrinsic value.” Sounds like a familiar sensation? Psychedelic drugs like LSD and magic mushrooms effectively do exactly the same thing.
However, researching these effects and coming to tangible conclusions is complicated by the fact that people experience cannabis highs differently, even if they are sharing the same joint.
Piomelli commented that the phenomenon of seeing the wonder in the everyday is common, but it is by no means universal.
So far, we have established that THC dials up our CB1 receptors while unplugging our brain’s default mode setting. But there is also one more trick it has up its sleeve.
A study carried out in 2017 showed that it can also trigger the release of dopamine, the “feel-good” neurotransmitter. This is important because it explains why, in the majority of cases, a cannabis high is an enjoyable experience.
The research also suggested that in the long term, it can blunt the effect of dopamine, which is why some heavy users of cannabis think they build up a tolerance and need to take more to feel the same effect.
Coming Down and Staying Safe
The effects of cannabis usually last for a couple of hours when the weed is smoked. With edibles, keep in mind that although you have to wait longer for them to take effect, they also stay in your system for longer.
There’s no doubt that cannabis affects your ability to drive or operate machinery, so only indulge if you know you don’t have to be anywhere else. After a few hours, the THC will leave the brain, carried away into the liver where it will be broken down and expelled from the body in urine.
Even if taking cannabis for recreational purposes is legal where you live, you need to take care of its use. There are still as many unknowns as knowns when it comes to the effects of THC, so it makes sense to err on the side of caution.
If you’re trying it for the first time, do so in the company of someone experienced who can help you along if things take an unpredictable turn. Always remember to start slow, especially with edibles as the “delayed action” can easily catch you out.
Last of all, remember that when it comes down to it, cannabis is a pharmacological substance and a potent one at that. If you are pregnant, or you think you might be, you should avoid it as it can cross from your bloodstream into the placenta.
Cannabis is also best avoided if you have ever been diagnosed with a mental condition or are at risk of psychosis. This is especially important when it comes to stronger synthetic cannabinoids like the ones mentioned earlier, which are best avoided entirely.