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View Full Version : Hey, I wrote this down. Some sites, I know, say several weeks for affected memory



beachguy in thongs
05-03-2006, 09:06 AM
Here's the site: www.hnrc.ucsd.edu

Some references may be brief. Adult Language, Nudity, and Violence.

Tests may have been done in 2001, but it was published in 2003.

They included three groups: heavy Cannabis users (recently), past heavy users (but, not recently), and a group of controls (very limited exposure to Cannabis).

Eight neurocognitive ability areas were tested. Six indicated that the effect could not be distinguished from zero. Learning and forgetting were the other two. The numbers of the differences being .21 for learning and .27 for forgetting (I don't know how to read those numbers, but I know that .21 means 1/5 of 1).

"These results can be interpreted in several ways. A statistically reliable negative effect was observed in the domain of learning and forgetting, suggesting that chronic long-term cannabis use results in a selective memory defect. While the results are compatible with this conclustion, the effect size for both domains was of a very small magnitude. The 'real life' impact of such a small and selective effect is questionable."

They asked the groups to abstain from cannabis and took urine analyses for the next month. "They were tested on days zero, 1, 7, and 28. After 28 days, all the heavy-users had undetectable THC levels. They noted subtle impairments on several neurocognitive tests in the active-users, who had just become abstinent. However, by 28 days, the active-users who had abstained for almost a month were indistinguishable from former heavy-users or non-using controls."

I forgot the rest.

beachguy in thongs
05-03-2006, 02:40 PM
Bump for tadaa. :smokin:

MaryJaneintheCloset
05-03-2006, 02:45 PM
Ahhh... ;)

beachguy in thongs
05-03-2006, 02:46 PM
Was that an extension of my last post?

MaryJaneintheCloset
05-03-2006, 02:48 PM
...yes...

beachguy in thongs
05-03-2006, 02:52 PM
Oh, :confused: , well then, I guess I should've said something else, along the lines of "haaaaaaaaaaaaaaaa".

MaryJaneintheCloset
05-03-2006, 02:56 PM
Haaaahaaaaaaaaaaaaaaa!

beachguy in thongs
05-03-2006, 03:06 PM
Go sell some land! Ahhhhhhh.

MaryJaneintheCloset
05-03-2006, 03:10 PM
Go sell some land! Ahhhhhhh.

Dude... that's creepy.

beachguy in thongs
05-03-2006, 03:15 PM
Which part, the land, or the "ahhhhhh"?

"Land Ho!"
-The Doors

minnesota man
05-03-2006, 03:17 PM
hey party people. I lost my avatar.

MaryJaneintheCloset
05-03-2006, 03:21 PM
The land.

Hi MM, how come you lost it?

beachguy in thongs
05-03-2006, 03:37 PM
Minnesota man, use this as your avatar until your user-name gets banned.

GhostFace2K
05-03-2006, 08:42 PM
Here's the site: www.hnrc.ucsd.edu

Some references may be brief. Adult Language, Nudity, and Violence.

Tests may have been done in 2001, but it was published in 2003.

They included three groups: heavy Cannabis users (recently), past heavy users (but, not recently), and a group of controls (very limited exposure to Cannabis).

Eight neurocognitive ability areas were tested. Six indicated that the effect could not be distinguished from zero. Learning and forgetting were the other two. The numbers of the differences being .21 for learning and .27 for forgetting (I don't know how to read those numbers, but I know that .21 means 1/5 of 1).
"These results can be interpreted in several ways. A statistically reliable negative effect was observed in the domain of learning and forgetting, suggesting that chronic long-term cannabis use results in a selective memory defect. While the results are compatible with this conclustion, the effect size for both domains was of a very small magnitude. The 'real life' impact of such a small and selective effect is questionable."

They asked the groups to abstain from cannabis and took urine analyses for the next month. "They were tested on days zero, 1, 7, and 28. After 28 days, all the heavy-users had undetectable THC levels. They noted subtle impairments on several neurocognitive tests in the active-users, who had just become abstinent. However, by 28 days, the active-users who had abstained for almost a month were indistinguishable from former heavy-users or non-using controls."

I forgot the rest.

The .21 and .27 numbers are most likely the adjusted R^2 (pronounced R-Squared) refer to the experiments "explaining power." (1 being perfect explaining power.) For example, a perfect correlation with a perfect R^2 of 1.00 means that the two effects are directly correolated (i.e. when it rains its wet outside) .21 and .27 are relatively weak R^2 numbers and they basically mean that memory loss can be correlated with long-term heavy cannabis users but it only explains about 20% of all possible variables that could be affecting memory loss. Basically, to a very small extent, cannabis could be attributed partially to why these users suffered memory loss. An acceptable R^2 (and this is opinionated, but most professionals agree) is around .5 or .6 and that offers a reasonable amount of explaining power. BUT the study does not mention anything about the direction of causality. Is it that cannabis causes memory loss, or do people apt to memory loss tend to smoke cannabis? (basically, does cannabis cause memory loss, or does memory loss cause people to be more susceptible to smoking cannabis) For example, does it rain because it's wet outside, or is it wet outside because it rained. The direction of causality is really important, and isn't as clear cut as the example i just gave. Although the numbers aren't very high, they are statistically different from zero, which means that cannabis (to some extent) may be related to memory loss.

beachguy in thongs
05-03-2006, 11:03 PM
Thanks, very much, for that explanation, GhostFace, but those weren't the only numbers.

However, in the case of the learning [-.21 99%CI (-.39,
-.022)] and forgetting [-.27 99%CI (-.49, -.044)] domains
the average effect sizes were found to be significant,
albeit of small magnitudes.

Okay, here is the site. http://www.hnrc.ucsd.edu/publications_pdf/348art2003.pdf

To answer your question about how it affects memory-loss, I've heard (but, I have no proof) that you, actually, do retain the information, in fact, more information is allowed into your head upon activation of the Cannabinoid receptors. They did not discuss the results of the tests on the seventh day, rather, just said that there were subtle differences.

But, the main factor is that in most of the studies, users were asked to abstain from a day to an hour before the test. If CB1 receptors are one of the most numerous in your Nervous System, maybe when they're settling down after being activated, you lose some of the "energy" to be able to retain information. Seeing that forgetting has been shown to affect the user, at it's highest degree, shortly after consumption, and melatonin has been shown to skyrocket, shortly after, I wonder what role melatonin plays in memory.

But, you're a brilliant man.

beachguy in thongs
05-03-2006, 11:12 PM
It looks like melatonin levels do affect memory. http://www.nootropics.com/melatonin/memory.html

Wait, I read that wrong, so I'm editing this.

beachguy in thongs
05-03-2006, 11:20 PM
extropians: Melatonin & Memory
European Journal of Pharmacology 1998 May 22;349(2-3):159-62 ... Melatonin facilitates short-term memory.
http://lists.extropy.org/exi-lists/extropians.3Q99/2153.html

Can't get to that application.

beachguy in thongs
05-03-2006, 11:23 PM
Memory Loss
As you grow older, you tend to become more forgetful. However, memory problems and difficulties in concentrating can happen at any age. Common causes include lack of sleep, depression, stress, anxiety, allergies, and hormonal imbalances. Poor nutrition is often thought to cause memory problems, so make sure you eat a healthy diet. Gentle exercise increases the flow of blood to the brain and may help to improve brain function.

I'm putting these up here, because I don't have much time, so sorry if I waste space.

beachguy in thongs
05-03-2006, 11:29 PM
http://emediawire.com/releases/2005/12/emw326511.htm

The nighttime use of artificial light stimulates human breast tumors according to a Dec. 19, 2005 press release from the National Institute for Environmental Health Sciences. This is the result of melatonin suppression. University scientists have invented light bulbs that do not suppress melatonin.