One of the advantages of retiring to a college\university town you can go and attend presentations by the local scholars as well as visiting ones. So I went and attended a talk by some researchers from the Neuroscience Center.
According to the speaker even one session with a recreational drug like pot permanently rewires connections. The rewiring is mostly meaningless, in some (yes a very small number!) its not. The more use the more rewiring again for mostly still meaningless, the threshold of the rewiring changing behavior is never reached. (Aside: As an anecdotal example I knew people who came back from Nam who were heroin users in Nam. The minute they hit the states, they stopped. No dramatic action, no rehab, no intervention etc. They just stopped! Yes their story, but I knew them well enough to give it credence.) But for each use again a small number of that population have their behavior modified. And so on !
I have always heard of the psychological term “addictive personalities”. Meaning a personality primed to react toward some sort of addition, gambling, sex, TV watching, thrill seeking (adrenaline rush!), cigarettes, pot, etc. This talk provided a possible physical reason for that term. Could it just be "confirmation bias" on my part? Maybe ? But maybe not ! So no not a stretch, or a leap or anything like that. Just thinking about new information, observing and integrating in personal information, observations and experiences. Yes my "speculative conclusion" could be wrong. If I get new information and its relevant I am open to changing my conclusion. !
Anyway it makes you think !