Yes. It depends on the age at which the cannabis is consumed. We have studies, for example, on THC and on many people around the world, and imaging studies in humans. Without a doubt the chronic use of cannabis does change the brain. It can change the brain in some aspects that are positive, obviously, and in others that are negative. In the developing brain, we see that it has a long-term impact. In prenatal exposure, adolescent exposure, and when you look at the brain of adults, you see sensitivity of reward, sensitivity of stress reactivity in the brain. We see changes that in some individuals are even reflective of a psychosis risk, which is consistent to what was mentioned before, that in some individuals that can occur.
Cannabis is not benign. It is definitely having an impact not only, as I said, on reward, but also cognition and emotional circuits. For example, PTSD activates the part of our brain, the amygdala, which is very important for emotional regulation. There have been studies to show that cannabis reduces that hyperactivity. However, the chronic use is definitely long term, impacting all brain circuits that we can see, and in other people as well, both in imaging....
You mentioned marijuana, cannabis, has been around for 6,000 years. Opioids are also natural and they've also been around for thousands of years. What we as humans have done is to leverage things in our environment to help us medicinally. To Dr. Jutras-Aswad's question, I think it's very important that we need to make sure we are standardizing in the same way that we develop all other medications.