You've been hoodwinked by "The Man"
Read the fine print: "For the study, researchers performed high-resolution structural magnetic resonance imaging (MRI) on 15 men who smoked more than 5 joints daily for more than 10 years. With an average age of 39.8 years and a mean duration of regular use of 19.7 years,
Who in the world smokes five joints (or more) a day?! Do you realize how much pot that is? That's like an 8th a day. Where do they get these guys? The lack of oxygen alone while smoking that much would cause the brain to shrink.
They have to do these studies where they get people to ingest massive quantities so that they can get some startling data. What would happen if they gave subjects 5 shots of vodka every day for ten years? They wouldn't have any subjects left at the end of the trials.
A little Googling reveals that the ORYGEN (the research outfit that did this study) gets the bulk of it's funding from a charitable trust in Australia called the Colonial Foundation. Reading the Colonial Foundation's Annual Report we find such gems as these from the chairman:
"The aim of the research is to fundamentally change the way in which drug policy decision-making occurs, and to ultimately reduce the harms from drug use."
Excuse me! but the aim of research should be to discover the truth, not change the way policy making decisions are made. I smell a big, stinky conflict of interest.
I also don't trust Aussies. They always want to fight me for some reason. Must be because they don't ingest enough pot to mellow their shit out.
On 6/27/08, My Wife wrote:Pot Damages the Brain
The marijuana debate continues, even though we have seen damage on SPECT scans from marijuana for many years. The article below reports on an important new study on marijuana and brain damage published in the Archives of General Psychiatry.
Medscape News June 6, 2008 — Long-term, heavy cannabis use has been linked with structural brain abnormalities, a new study shows.
Investigators at the University of Melbourne, Australia, found the hippocampus and the amygdala tend to be smaller in heavy cannabis users compared with nonusers, with average volume reductions of 12% in the hippocampus and 7.1% in the amygdala. Cannabis use was also associated with subthreshold symptoms of psychotic disorders.
Cannibis use is a controversial topic; the authors note there are many who believe cannabis is relatively harmless and should be legally available. However, the current findings suggest otherwise.
“These findings challenge the widespread perception of cannabis as having limited or no neuroanatomical sequelae. Although modest use may not lead to significant neurotoxic effects, these results suggest that heavy daily use might indeed be toxic to human brain tissue,” they write.
It is estimated that 15 million Americans use cannabis in a given month, that 3.4 million are daily users with a duration of 12 months or more, and that every year 2.1 million start using the drug.
Led by Murat Yücel, PhD, the study is published in the June issue of Archives of General Psychiatry.
Mechanism Unclear
According to the authors, this is the first human study of long-term heavy cannabis use to show marked hippocampal volume reductions. The findings, they add, are consistent with the view that cannabis use increases the risk of psychotic symptoms.
For the study, researchers performed high-resolution structural magnetic resonance imaging (MRI) on 15 men who smoked more than 5 joints daily for more than 10 years. With an average age of 39.8 years and a mean duration of regular use of 19.7 years, the subjects had no history of polydrug abuse or neurologic/mental disorder.
MRI results from these subjects were then compared with those of 16 matched controls who did not use cannabis.
Despite the large magnitude of effect, it is unclear whether volumetric reductions are due to neuronal or glial loss, a change in cell size, or a reduction in synaptic density. The investigators say more research is needed to explain the underlying mechanisms.
The study also showed hippocampal volume in cannabis users was inversely correlated with cumulative exposure to the drug in the left, but not right, hemisphere — a finding that suggests that “the left hippocampus may be particularly vulnerable to the effects of cannabis exposure and may be more closely related to the emergence of psychotic symptoms.”
According to the investigators, “further prospective, longitudinal research is required to determine the degree and mechanisms of long term cannabis-related harm and the time course of neuronal recovery after abstinence.”
Arch Gen Psychiatry. 2008;65:694-701.
