Josh, I'd love to see a replication of the source studies of that article. The article itself seems a "little" biased.
Ok, let's get to some unbiased scientific articles. This first one has to do with the claim that marijuana has no effect on memory beyond the period when you're high.
Snippet from "Marijuana: A Decade and a Half Later, Still a Crude Drug With Underappreciated Toxicity" as written by Schwartz, Richard H. and published in Pediatrics; Feb2002 Part 1 of 2, Vol. 109 Issue 2, p284, 6p.
Short-Term Memory Impairment
Impairment of short-term memory is one of the least debatable and most troublesome adverse effects of marijuana.( n38-n43) During the past 15 years, there has been important research in this area in adults, high school students, and college students. The single most marked effect of marijuana smoking seems to be an impairment of our ability to process newly learned material and store it for future use. Given the increase in use of marijuana by 8th-grade students since 1992, this has alarming potential significance.
Seven of 8 studies published before 1988 found lingering selective deficits in recent memory in adult, chronic marijuana smokers as compared with control subjects.( n38) Two of those 8 studies initially found no evidence of memory impairment. However, on reevaluation of the same subjects 1 decade later, short-term memory impairment was demonstrable. Does impairment of short-term memory linger after the marijuana euphoria has passed? In real life, as in the laboratory setting, short-term memory impairment secondary to smoking marijuana has been documented to cause major problems. Having trouble remembering things is the most bothersome adverse effect mentioned by 100 adult, daily marijuana smokers.( n44) In a study of 10 high school students who had been daily marijuana smokers for a mean of 7 months, marijuana use was confirmed by twice-weekly tests for urine THC.( n45) Excluded from the study were those who were heavy drinkers and those with low IQ test scores. During the 6-week study period, participants were supervised 24 hours a day to ensure that they could not continue to smoke marijuana. A neuropsychology masters-level candidate administered auditory and visual short-term memory tests after a 48-hour washout period and again 6 weeks later. Impairment of both visual and auditory short-term memory was demonstrated. Control groups did not show this impairment. In a well-publicized study of 65 college students who smoked marijuana frequently and 64 who smoked it occasionally, daily use of the drug was associated with impairment of "executive functions" such as learning of lists and attention to homework.( n46) Residual neuropsychological impairment of executive functions was found to carry over well past the period of intoxication. Verbal fluency was noted to be impaired in many of the daily marijuana smokers. In the accompanying editorial to this published study, it was suggested that the most plausible interpretation of the findings was that heavy marijuana smoking produces alterations of cannabinoid-specific brain function or structure.( n47)
The citations:
(n38.) Schwartz RH. Heavy marijuana use and recent memory impairment. Psychiatr Ann. 1991;21:80-83
(n39.) Block RI, Ghoneim MM. Effects of chronic marijuana use on human cognition. Psychopharmacology (Berl). 1993;110:219-228
(n40.) Solowij N, Michie PT, Fox AM. Differential impairments of selective attention due to frequency and duration of cannabis use. Biol Psychiatry. 1995;37:731-739
(n41.) Kurzthaler H, Hummer M, Miller C, et al. Effect of cannabis use on cognitive functions and driving ability. J Clin Psychiatr. 1999;60:395-399
(n42.) Solowij N. Cannabis and Cognitive Functioning. Cambridge, England: Cambridge University Press; 1998
(n43.) Ameri A. The effects of cannabinoids on the brain. Prog Neurobiol. 1999;58:315-348
(n44.) Hendin H, Haas AP, Singer P, et al. Living High: Daily Marijuana Use Among Adults. New York, NY: Human Sciences Press; 1987
(n45.) Schwartz RH, Gruenewald PJ, Klitzner M, Fedio P. Short-term memory impairment in cannabis-dependent adolescents. Am J Dis Child. 1989;143:1214-1219
(n46.) Pope HG Jr, Yurgelun-Todd D. The residual cognitive effects of heavy marijuana use in college students. JAMA. 1996;275:521-527
(n47.) Block RI. Does heavy marijuana use impair human cognition and brain function? JAMA. 1996;275:560-561
(n48.) Van Hoozen BE, Cross CE. Marijuana: Respiratory tract effects. Clin Rev Allergy Immunol. 1997;15:243-269
This clearly states the exact opposite of the idea that marijuana has no long term effects. Period. If anyone wants me to find an individual cited article I may be able to.
Though to show I'm not biased, I may be able to link anyone interested in study that shows that previous or current light use of marijuana does not decrese IQ in a 70-person sample size (however consistant, heavy -more than 5 joints per week- use did result in a decrease in IQ score.) Josh, that's one of the reasons I'd love to see the studies cited in your article, the general finding seems similar, but I'd like to see how well the other parts of the study match up.
Interesting stuff, all of it. At the very least I hope I can
everyone a good kick in the fanny. lol! It's easy to SAY something is one way or another, but it's another when suddenly you have evidence stating the contrary.