4 ms·

It doesn't seem like a stretch to me to suggest that the same (heavily documented and confirmed) effects apply to first-time adult users. Certainly alcohol use

It doesn't seem like a stretch to me to suggest that the same (heavily documented and confirmed) effects apply to first-time adult users. Certainly alcohol use affects teenagers' brains more than adults, yet still does affect adults. This seems like common sense. Most substances behave this way. Likewise, the studies all track teenagers over decades, who then became adults. This is the most common usage pattern.

herbst 5y ago
Now it's common sense and whatnot without any scientific study backing it. Mkey. Because most substances behave this way and alcohol and weed has so much in common. Obviously Dude stop
- ceilingcorner 5y ago
  This took me 30 seconds to find. Blest-Hopley et al. [21] showed that both adolescent and adult cannabis users exhibited deficits compared to controls but in different brain areas, suggesting age-related risks at both developmental periods [21]. Additionally, Scott et al. [19] found small but significant effect sizes for the relationship between heavy cannabis use and cognition in both adolescents and young adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6394430/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6394430/ I really don't know what you are trying to argue for, other than to just have your already-existing opinions validated. You are arguing that for people that only use cannabis first as an adult, it has no negative effect? Because it is quite clear that usage as a teenager has negative IQ effects later on.
  - herbst 5y ago
    Took me 30 seconds to find this https://www.pnas.org/content/113/5/E500 https://www.pnas.org/content/113/5/E500 > Among twin pairs discordant for marijuana use, we assessed intelligence quotient (IQ) score changes while adjusting for the effects of genetic influences and other factors shared by members of the same twin pair. Results suggest that familial confounds underlie the association between adolescent marijuana use and declining IQ scores So we are back to my initial suggestion that it's environmental related more than anything. Yes I do have an opinion, because I think saying shit like 'just like with alcohol' when we talk about cannabis, or generally suggesting that cannabis leads to a school dropouts and what not are old ideas that should not be so present in a modern, scientific, society Edit:// adding the conclusion > In the largest longitudinal examination of marijuana use and IQ change, using two samples to replicate results and a genetically informative design, we find little evidence to suggest that adolescent marijuana use has a direct effect on intellectual decline. Although marijuana users showed greater decline than nonusers in areas of Gc, the presence of baseline differences before marijuana involvement, the lack of a dose–response relationship, and an absence of meaningful differences between discordant siblings lead us to conclude that the deficits observed in marijuana users are attributable to confounding factors that influence both substance initiation and IQ rather than a neurotoxic effect of marijuana.
    - ceilingcorner 5y ago
      > environmental related more than anything. It is likely both... that's usually what happens. This study also stopped tracking the twins at age 20, which is far younger than most other studies. Although our study evaluated a subset of subjects who had been daily users over the course of 6 mo to a year, all participants were still young adults at their last assessment. Perhaps regular use over a more prolonged period would result in greater differentiation across groups. This is a possible explanation for the discrepancy of our findings from those of Meier et al. (23), whose subjects were aged 38 y at their last assessment. We additionally were not able to differentiate current heavy users from former heavy users, and thus our results cannot disentangle the acute from nonacute effects of marijuana use on intellectual functioning. To me this makes the conclusions pretty useless. They are still adolescents, not adults. They haven't used cannabis over a long period of time, which seems to be the real determining factor. > cannabis leads to a school dropouts Yeah, well that's my personal experience. I watched it happen in my own life. If that's not good enough for your "modern, scientific, society", why bother making this topic? I thought you wanted personal experiences.
ipaddr 5y ago
It is a huge stretch. I'm sure there have been studies with adults why not reference them.

herbst 5y ago

Now it's common sense and whatnot without any scientific study backing it. Mkey. Because most substances behave this way and alcohol and weed has so much in common. Obviously Dude stop

ceilingcorner 5y ago
This took me 30 seconds to find. Blest-Hopley et al. [21] showed that both adolescent and adult cannabis users exhibited deficits compared to controls but in different brain areas, suggesting age-related risks at both developmental periods [21]. Additionally, Scott et al. [19] found small but significant effect sizes for the relationship between heavy cannabis use and cognition in both adolescents and young adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6394430/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6394430/ I really don't know what you are trying to argue for, other than to just have your already-existing opinions validated. You are arguing that for people that only use cannabis first as an adult, it has no negative effect? Because it is quite clear that usage as a teenager has negative IQ effects later on.
- herbst 5y ago
  Took me 30 seconds to find this https://www.pnas.org/content/113/5/E500 https://www.pnas.org/content/113/5/E500 > Among twin pairs discordant for marijuana use, we assessed intelligence quotient (IQ) score changes while adjusting for the effects of genetic influences and other factors shared by members of the same twin pair. Results suggest that familial confounds underlie the association between adolescent marijuana use and declining IQ scores So we are back to my initial suggestion that it's environmental related more than anything. Yes I do have an opinion, because I think saying shit like 'just like with alcohol' when we talk about cannabis, or generally suggesting that cannabis leads to a school dropouts and what not are old ideas that should not be so present in a modern, scientific, society Edit:// adding the conclusion > In the largest longitudinal examination of marijuana use and IQ change, using two samples to replicate results and a genetically informative design, we find little evidence to suggest that adolescent marijuana use has a direct effect on intellectual decline. Although marijuana users showed greater decline than nonusers in areas of Gc, the presence of baseline differences before marijuana involvement, the lack of a dose–response relationship, and an absence of meaningful differences between discordant siblings lead us to conclude that the deficits observed in marijuana users are attributable to confounding factors that influence both substance initiation and IQ rather than a neurotoxic effect of marijuana.
  - ceilingcorner 5y ago
    > environmental related more than anything. It is likely both... that's usually what happens. This study also stopped tracking the twins at age 20, which is far younger than most other studies. Although our study evaluated a subset of subjects who had been daily users over the course of 6 mo to a year, all participants were still young adults at their last assessment. Perhaps regular use over a more prolonged period would result in greater differentiation across groups. This is a possible explanation for the discrepancy of our findings from those of Meier et al. (23), whose subjects were aged 38 y at their last assessment. We additionally were not able to differentiate current heavy users from former heavy users, and thus our results cannot disentangle the acute from nonacute effects of marijuana use on intellectual functioning. To me this makes the conclusions pretty useless. They are still adolescents, not adults. They haven't used cannabis over a long period of time, which seems to be the real determining factor. > cannabis leads to a school dropouts Yeah, well that's my personal experience. I watched it happen in my own life. If that's not good enough for your "modern, scientific, society", why bother making this topic? I thought you wanted personal experiences.

ipaddr 5y ago

It is a huge stretch. I'm sure there have been studies with adults why not reference them.