It’s common knowledge that the consumption of cannabis creates a “high” for the user. There is plenty of anecdotal evidence of the effects – users report feelings of euphoria, heightened empathy, altered physical sensations, increased creativity, introspection, metacognition, and a host of other deviations from sober brain function. In high doses, some users even report experiences that sound almost psychedelic. So, just how does THC affect the brain?
As more of the world continues to legalize and embrace cannabis, more knowledge is becoming readily available about how cannabis actually works. You may already know that THC (abbreviated from Δ9-tetrahydrocannabinol) is the primary psychoactive component of cannabis. This is certainly true, but there are many other compounds in cannabis that produce their own effects or modify the effects of the other compounds.
More Than Just THC
THC is the most well-known chemical in the class known as cannabinoids. There are more than 113 different cannabinoids that can be found in cannabis, and while none of them have an effect as significant as THC’s, many of these compounds can induce varying effects as well. But how does THC interact with our brains?
Prior to the 1980s, scientists had thought that cannabinoids took effect by interacting with cell membranes. We now know that they work by interacting with specific cannabinoid receptors. There are two primary types of cannabinoid receptors, known as CB1 and CB2. CB1 receptors can be found in the brain, nervous system, lungs, liver, and kidneys. CB2 receptors are found in the spleen, immune system, and the gastrointestinal system.
The body creates two natural chemicals called 2-AG and anandamide, both of which act on CB receptors. This explains why our body can interact with THC and cannabinoids in the first place – THC is extremely similar to anandamide, and so it (and the other cannabinoids) can bind to the CB receptors. The differences between THC and the body’s natural cannabinoids (endocannabinoids) are what create the previously mentioned effects of a high.
THC isn’t the only important element found in cannabis, though. CBD, or cannabidiol, is the second-most prevalent cannabinoid found in the marijuana plant. CBD doesn’t have any of the psychotropic effects that THC does, but it does influence the effects of the plant. This is the compound that is responsible for cannabis’ tendency to relax the user, reduce anxiety, and promote sleep. This is also the more useful compound when it comes to using marijuana medicinally, as CBD has been shown to help treat epilepsy, seizures, pain, inflammation, PTSD, Crohn’s disease, and more.
Due to the ongoing legalization of cannabis, more and more varieties of cannabis are becoming available as growers gain access to more efficient, larger-scale, more precise methods of growing, nurturing, and breeding the plants. It is currently possible (in most areas where cannabis has been legalized) to buy strains that have been bred for a high THC content, a high CBD content or a mix of both. However, there is some evidence that CBD helps counteract some of the less-pleasant effects of THC, such as temporary short-term memory loss, so that may be worth keeping in mind.
THC And Terpenes
Finally, there is one more set of compounds that affects the type of high you’ll experience when you consume cannabis. These are terpenes, compounds that provide the basis for the essential oils that can be derived from various plants. They are the compounds that give different plants their different flavors and smells. They are present in all kinds of plants, and cannabis plants produce over 100 different terpenes. These compounds interact with THC and CBD in a variety of different ways – some terpenes enhance the effects of the two dominant compounds, while others tend to counteract them to some extent, softening the overall effect. Either way, the complex relationship between all of these compounds is known as the entourage effect.
Terpenes are what give different strains of cannabis their different scents, as well as the slight variations in effect. Leafly has a useful graphic that contains information on some of the more common terpenes, such as their effects and their smells. With a combination of research and some personal experience, you can learn to discern the differences between strains and accurately anticipate the effects that they are likely to have, simply based on their scents.
Cannabis contains many compounds that have a perceptible effect on the user. These chemicals have a complex relationship with each other that affects the high, but as cannabis research becomes more prevalent, we will continue to understand more about how all of these molecular pieces work together.
For more information on THC and the brain, be sure to check out Calm Collectiv’s interview with Nick Jikomes.