First of all, let's just give the listeners an idea about how these substances, psychedelic substances in general, are able to influence the way our brain works and maybe why some substances in general can influence our brain activity and some cannot.

Okay, so maybe a useful way to approach that important question is just to start off with some basic definitions.

So there are a number of terms that are Similar and therefore confusing, but let's briefly go through them just to unpack them for listeners.

So if we describe a substance as psychoactive, it just means that it's a chemical that affects perception or mood or consciousness or cognition or behavior, just in a broad sense.

So many substances are psychoactive like alcohol or tobacco or Valium or sleeping pills or antidepressants.

Some are intoxicating.

like alcohol or cocaine or cannabis.

Could you please elaborate on that? For example, if a person suffering from post-traumatic stress disorder or depression reaches out to their to their psychiatrist and asks for a prescription for medicinal marijuana, what are the factors that a clinician takes into account before deciding whether this particular patient is a good candidate or not?