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Marijuana as a Nootropic

neurogenesis marijuana cannabinoids

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#1 Wurzel Bagman

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Posted 29 August 2010 - 07:17 PM


I was wondering what other's experiences with marijuana as a nootropic are. I believe that when in a controlled dose using a vaporizer marijuana is a great nootropic. When i vaporize small amounts daily I believe my right brain's abilities are greatly enhanced. I begin to express a lot more empathy. My ability and confidence to be social is boosted 10 fold. I find that my verbal fluency also gets a boost (i do significantly better on a word building game on Lumosity) Also my senses are sharper and my mind clearer and more focused.

Some people might think it impairs memory and makes you sluggish but with the small amount i use (0.25-.5grams) i havent been affected by that at all... in fact i find the opposite to be true. I have a working memory game that involves remembering the spacial position of blocks on a grid from Lumosity and I recently beat my high score high (i've played the game hundreds of times prior so my scores are quite difficult to beat)

I've seen some recent studies showing that marijuana can stimulate brain cell growth and may be good for memory.
http://www.newscient...-the-brain.html
http://www.wired.com...arijuana-could/

Does anyone know if there are any synergistic effects with piracetam? I find this combination to be the ultimate nootropic regime for me. I feel all around calm, focused, energetic and "in the Now" when ive combined the two (piracetam doesn't seem to work especially well by itself for me). I also remember Isochroma mentioning marijuana (perhaps that was aiding in his creative literary ability?).

Edited by chrono, 13 November 2011 - 04:05 PM.

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#2 medievil

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Posted 29 August 2010 - 09:20 PM

reduce social anxiety significantly

For most people it actually makes SA a ton worse (even after the drug wears off).

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#3 Logan

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Posted 29 August 2010 - 11:13 PM

reduce social anxiety significantly

For most people it actually makes SA a ton worse (even after the drug wears off).


That was never my experience. Everyone I know that is a regular MJ user does so in order to both function better at work and better enjoy social situations. I think it depends on the person and the kind of MJ you are using.
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#4 gamesguru

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Posted 30 August 2010 - 03:31 AM

There is indisputable evidence that the administration of exogenous cannabinoids catalyzes hippocampal neurogenesis. This means more, albeit marginally more, neurons grow and thus the calculative complexity of the hippocampus increases; it can handle more calculations. However, if one believes in the well-established Hebbian theory of synaptic plasticity, then it is a personal truth that exogenous cannabinoids decrease the communicative efficiency of cells in the hippocampus. The former statement stems from this fact: exogenous cannabinoids temporarily cause the majority of electrical activity in the hippocampus to stop, and so the Hebbian theory that "cells which fire together, wire together" dictates a decrease in communicative efficiency with the administration of exogenous cannabinoids to the CNS.
The clinical significance of these opposing phenomenon (increased calculative complexicty vs. decreased communicative efficiency) is a subject of great scientific debate, as is the dosing schedule which offers optimal equilibrium. I believe I have located a dosing schedule very near this equilibrium. At such a dosing schedule, the stereotypical disruption of memory functionality is transient and after the high subsides, it appears (based on self-imposed neurological tests as well as personal experience) that what persists is a hippocampus which functions better than baseline. Many people, in my opinion, use too high of a dose and as a result suffer from memory impairment and learning down-regulation (probably due to decreased communicative efficiency between cells of the hippocampus and possibly the prefrontal cortex). In any event, quantitatively speaking, the up-regulated learning is not terribly significant, but it cannot hurt as long as your behavioral schedule permits your productivity not to suffer. I can provide more information on this topic upon request.

I believe all other factors are more insignificant. The temporary increased communication between the hemispheres of the brain seems to possess little long-term therapeutic use. It seems to be only of temporary use in increasing complexity of abstract thinking capabilities and sensory perception. I have seen no research papers indicating long-term upregulation of thinking abilities, and to the best of my abilities, based on my personal experience I cannot honestly assert the existence of a long-term benefit in this regard either.

It is also important to consider that biological individuality means people respond marginally differently to cannabinoids and there are many factors here that the limited research on this topic (thank you government!) has yet to unveil.

Edited by dasheenster, 30 August 2010 - 03:38 AM.

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#5 Wurzel Bagman

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Posted 30 August 2010 - 07:25 AM

There is indisputable evidence that the administration of exogenous cannabinoids catalyzes hippocampal neurogenesis. This means more, albeit marginally more, neurons grow and thus the calculative complexity of the hippocampus increases; it can handle more calculations. However, if one believes in the well-established Hebbian theory of synaptic plasticity, then it is a personal truth that exogenous cannabinoids decrease the communicative efficiency of cells in the hippocampus. The former statement stems from this fact: exogenous cannabinoids temporarily cause the majority of electrical activity in the hippocampus to stop, and so the Hebbian theory that "cells which fire together, wire together" dictates a decrease in communicative efficiency with the administration of exogenous cannabinoids to the CNS.
The clinical significance of these opposing phenomenon (increased calculative complexicty vs. decreased communicative efficiency) is a subject of great scientific debate, as is the dosing schedule which offers optimal equilibrium. I believe I have located a dosing schedule very near this equilibrium. At such a dosing schedule, the stereotypical disruption of memory functionality is transient and after the high subsides, it appears (based on self-imposed neurological tests as well as personal experience) that what persists is a hippocampus which functions better than baseline. Many people, in my opinion, use too high of a dose and as a result suffer from memory impairment and learning down-regulation (probably due to decreased communicative efficiency between cells of the hippocampus and possibly the prefrontal cortex). In any event, quantitatively speaking, the up-regulated learning is not terribly significant, but it cannot hurt as long as your behavioral schedule permits your productivity not to suffer. I can provide more information on this topic upon request.

I believe all other factors are more insignificant. The temporary increased communication between the hemispheres of the brain seems to possess little long-term therapeutic use. It seems to be only of temporary use in increasing complexity of abstract thinking capabilities and sensory perception. I have seen no research papers indicating long-term upregulation of thinking abilities, and to the best of my abilities, based on my personal experience I cannot honestly assert the existence of a long-term benefit in this regard either.

It is also important to consider that biological individuality means people respond marginally differently to cannabinoids and there are many factors here that the limited research on this topic (thank you government!) has yet to unveil.


Thank you very much for this post. I like the equilibrium idea you're talking about. I think I've found a good balance but would be interested in finding out what your dose/schedule is. I would also like more information on this topic :)

Edited by ptamaddict, 30 August 2010 - 07:26 AM.


#6 winston

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Posted 31 August 2010 - 01:17 AM

Vaporizing MJ usually produces a more "clear headed" high than smoking. Why this is I'm not sure, but I would encourage anyone who liked MJ except for the brain fog to give it a shot.

Personally I didn't enjoy MJ much till one time when I smoked quite a bit while on a large benzo dose. Now my brain associates it with relaxation as opposed to heightened anxiety. At least, this is my best guess.

From anecdotal readings, it seems that occasional use of marijuana doesn't cause any long term cognitive harm. And, given how much it's affects vary from person to person, I think you've just got to try it out to see if it's beneficial to your thinking. Very much a subjective thing as, IMO, it's affects are as much the outcome of it's interaction with your psychological make up as your chemical.

#7 ajnast4r

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Posted 31 August 2010 - 01:25 AM

ive heard a few people say this, but that type of reaction is the exception not the rule... most people have decrease cognitive function and increase anxiety.

#8 NR2(x)

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Posted 31 August 2010 - 05:22 AM

However, if one believes in the well-established Hebbian theory of synaptic plasticity, then it is a personal truth that exogenous cannabinoids decrease the communicative efficiency of cells in the hippocampus. The former statement stems from this fact: exogenous cannabinoids temporarily cause the majority of electrical activity in the hippocampus to stop, and so the Hebbian theory that "cells which fire together, wire together" dictates a decrease in communicative efficiency with the administration of exogenous cannabinoids to the CNS.

Its good to see someone using hebbian plasticity to basis the models on. I might disagree with the conclusion that you have drawn depending on the meaning you ascribe to communicative efficiency.
Yes MJ facilitates Long Term Depression between Neurons, that is the probability of two neurons mutual firing could be more easily decreased if MJ is present. But communicative efficiency should be judge in relation to the the network as a whole. Imagine if every neuron fired at exactly the same time. THere would be no product or design to the EMF and hence no conciousness or computational power. THe same would apply if there was no hebbian plasticity aswell. My point is that its a very complex phenomia, and very qualified statements with many assumptions are required before any real statement can be made.

Roughly this is how i understand it;
Have you consider that its possiable that the major limit to the brain is its proir learning. Eg Excessive Long Term Potentiation makes it hard to learn, so by increasing LTD, we can faciliate great LTP or learn. This is important because most of the excessive learning incodes information that is very narrow and redundant. Furthermore most of the material was laid while we were toddlers and therefore is compromised by lack of understanding and influence. I think this model could explain both the increased calculative complexitiy and the inverse U shaped effect curve.

Got a feeling the MJ positive mechanism of action is not through CB receptors but no proof; HU211

#9 Wurzel Bagman

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Posted 31 August 2010 - 03:46 PM

I should just clarify what i mean when i say cannabis makes me more focused, social, energetic. It's not the immediate effects that are the most important to me. Those are enjoyable and relaxing but i'm not super focused or energetic then. It's the after effects from vaporizing that really benefits my day to day life. The residual highness that is mild and lingers a day or two. So when i vaporize at night the next day i feel alert and in the moment.

Dasheenster, or anyone else, can you tell me a little bit more about the increased calculative complexicty in the hippocampus stuff? Like in layman's terms what that means for the individual? When i'm able to relate and connect ideas that wouldn't normally be connected together, could that be from having an increased calculative complexicty? Would this be why many comedians consume cannabis? The complexity of their hippocampus' neurons allow them to synthesis ideas that others would have a difficult time to spontaneously do.
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#10 Pike

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Posted 31 August 2010 - 04:40 PM

i do sincerely doubt that MJ works as a sustainable, consistent nootropic for the majority of people who take it. i don't know one person who has been on MJ and did any better in school because of it, nor have i met someone who appears to be benefitting from "enhanced cognition" whilst on it. in fact, i'd say just the opposite.

that aside, there might be a slight possibility it could have some sort of cognitive benefit. like with many medicines used as drugs, most theraputic effects are pretty much void beyond low doses. i personally don't have what it takes to enjoy MJ, but i wonder if a low dose, if taken properly as a medicine (i.e. consistent administration at consistent times) could bring about some benefit.

#11 medievil

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Posted 31 August 2010 - 06:43 PM

Ive read that certain people with ADHD find MJ therapeutic, not in my case, more like the opposite, but it does have therapeutic potential for some, but i agree that for most it will just be a dumb drug.

#12 medievil

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Posted 31 August 2010 - 06:57 PM

In this attachement is a review of all the evidence wheter cannabinoids are neurotoxic. This one dates back from 2004 tough so new evidence may have showed up, here's the summary of the paper:

Summary
The results from the various experiments investigating chronic cannabinoid treatment on neuronal morphology are summed up in table 1. In the rat experiments reported here, all but one reported that cannabinoids alters neuronal morphology, particularly in the hippocampus, and the one study that did not used an unknown sample size and techniques. In the rhesus monkey the results have been inconclusive, but seem to show that 1 2.6% THC cannabis cigarette a day is not enough to induced neurohistological changes.
Studies investigating the neurochemical effect of chronic cannabinoid treatment have had mixed results (Table 2). It has been reported that administration of cannabinoids to pregnant rats produced neurochemical alterations in their offspring up to 40 days after weaning (Walters & Carr, 1986), but when this experiment was repeated, the alterations found were completely different (Walters & Carr, 1988). Other experiments have found no significant alterations in the neurochemical systems investigated in either the rat or the rhesus monkey. It is possible that there is a critical period in which cannabinoids can alter the neurochemistry of the rat.
Experiments investigating the behaviour of rats and rhesus monkeys have reported that it is altered, even after a significant washout phase, after chronic cannabinoid treatment (Table 3). The one experiment which did not show this conclusively was Nakamura et al., (1991), which showed that the behavioural effects were reversed after a 30 day washout, but not a 15 day washout phase. It is unknown whether this is due to the persistence of cannabinoids in the plasma. It has been convincingly shown that cannabinoids in doses between 5 and 20mg/kg produce a residual change in behaviour in the rat, and that this change is negative in nature, as it involves a decrease in spatial processing shown by reduced performance in 8 and 12-arm radial mazes. In order to draw hard conclusions about the action of chronic cannabinoids in monkeys, more experiments need to be run.
In humans it has been shown that cannabinoids probably do not produce any change in brain volume (Table 4). Block et al., (2000b) reported that during abstinence, cannabinoids produced a change in regional brain flow, but the abstinent period was not long enough to reasonably conclude that this was not an effect of residual cannabinoids in the blood or cannabinoid withdrawal.
Investigations into the cognitive state of cannabis users have yielded very interesting results (Table 5). The findings of Pope and Yurgelun-Todd (1996) indicate that the chronic cannabinoid usage results, which showed cognitive impairment, were probably due to an insufficient washout phase. Fletcher et al., (1996) reported that, even after a washout phase presumed to be long enough for residual cannabinoids to be cleared and withdrawal symptoms to subside, subjects who had used cannabinoids for a mean length of 34 years performed significantly worse than their age matched controls in short term memory tasks. On the other hand, it was reported that subjects who had used for a mean of 9 years did not. This experiment perhaps suggests that significant cognitive impairment only happens after extended cannabinoid treatment. Pope et al (2001) showed that subjects who had used cannabis more than 5000 times, but had been generally abstinent for the last 3 months, performed no worse than the controls. They also reported that while subjects who had used cannabis more than 5000 times and were still using daily performed significantly worse than the controls, they performed no worse than the controls after 28 days abstinence.
As mentioned earlier, in order for a chemical to satisfy to ICON definition for neurotoxicity, it must produced a physical change (neurochemical/neurohistological/ neurological) and this change must be associated with a negative behavioural effect. Cannabinoids have satisfied this criterion in doses between 8 and 20mg/kg in the rat, but not in the rhesus monkey. In humans there is no clear evidence that chronic cannabinoid physical alters the brain or cognition, so there is no evidence that cannabinoids are neurotoxic.
Even though cannabinoids have been shown to be protective against many induced neurotoxic events (for review, see Fowler, 2003) in a model proposed by Guzman (2003), it could be possible for cannabinoids to be protective against large neurotoxic insults, yet cause neurotoxicity slowly over time.
Studies investigating rhesus monkeys that are dosed in a more controlled fashion than smoke, and at a higher dose than 1 cannabis cigarette are currently lacking. Instead of getting further away from human users, this could in fact bring the experimental paradigm closer to human users, who often smoke more than one cannabis cigarette a day (Foltin et al., 1989). Also, studies investigating the cognitive function of humans who have used cannabis for 30 years or longer could show whether permanent cognitive impairments can be induced by extended cannabis use.
In conclusion, there is evidence that chronic cannabinoid treatment is neurotoxic to the rat, but not to the rhesus monkey or to humans.

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Edited by medievil, 31 August 2010 - 07:11 PM.

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#13 Pike

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Posted 31 August 2010 - 06:59 PM

Ive read that certain people with ADHD find MJ therapeutic, not in my case, more like the opposite, but it does have therapeutic potential for some, but i agree that for most it will just be a dumb drug.


i could understand the logic behind that. it might quiet down racing thoughts. in my case of adhd, however, the anxiety i got from it only made the racing thoughts worse.

#14 medievil

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Posted 31 August 2010 - 07:07 PM

Some further interesting study's on cannibinoids.
http://www.nature.co...s/6605248a.html

http://www.sciencedi...b4997e57c829176

http://mct.aacrjourn...9-0448.abstract

http://www.jleukbio....t/full/82/3/532

http://www.jci.org/a...16116/version/1

http://www.cancer-th...i,_103-116.html

Offcourse i would cast some doubt on those study's, this doesnt mean at all that smoking MJ will prevent cancer, i beleive that this was discussed before on another forum and that MJ is also immumosupressive wich then again could increase cancer risk, could be completely wrong tough, still interesting food for tought, now that were talking about MJ, there's some interesting data on cannabinoids worth discussing.

Edited by medievil, 31 August 2010 - 07:10 PM.

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#15 John Barleycorn

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Posted 01 September 2010 - 03:22 AM

Vaporizing MJ usually produces a more "clear headed" high than smoking. Why this is I'm not sure, but I would encourage anyone who liked MJ except for the brain fog to give it a shot.


Most vapourisers aren't hot enough to get all the CBN/CBD, so they subjectively increase the THC ratio. I have heard that if the leftovers are subsequently combusted, it can have a tranquillising effect. In fact, that's what most heavy smokers want, because they have become desensitised to the THC effects. They might as well just smoke an Indica strain.

#16 John Barleycorn

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Posted 01 September 2010 - 03:29 AM

Have you consider that its possiable that the major limit to the brain is its proir learning. Eg Excessive Long Term Potentiation makes it hard to learn, so by increasing LTD, we can faciliate great LTP or learn.


It stands to reason that breaking of connections is just as important to learning as is making of connections. I have seen similar claims made in relation to the MOA of oxytocin.

#17 e Volution

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Posted 01 September 2010 - 04:37 AM

Marijuana is to me:

1. A powerful nootropic. It enhances many of my creative thinking abilities, and I view it just as a general 'enhancer' to almost any activity from watching a movie or eating food, to having sex, to reading interesting scientific ideas on the web. It just generally makes me "think differently" and allows me to make cognitive connections I normally could not. For me a long car trip can go from most boring activity ever to enjoyable if I get stoned for example.

2. Incredibly bad for social interactions. I become socially inept under the influence of Marijuana, even around close friends. Growing up I was a bit shy and suffered from social anxiety, however in my early 20's I made a directed effort to get over this which paid great dividends to the point where I am now very sociable and most friends I have made recently cannot imagine me as shy (if anything the opposite--this is probably due to my constant pushing against my natural quietness/shyness and trying to be outgoing/extroverted).
2.1 As a side note here, a real issue I have with social anxiety under Marijuana is looking people in the eyes. I have noticed an incredibly powerful inhibition of this if I simply put on a pair of dark sunglasses. It is something about not having that direct eye contact which instantly puts me more at ease. Anyone shed any insight on this?

3. Paranoid. Related to above, I think the paranoia is underlying much of my difficulties with social interactions, I am too "in my head" and thinking about what to say or what the person I am talking to is thinking about me or what I have just said. Whilst I still suffer from these feelings when high, I have mostly learned to ignore them when around close friends, simply due to reinforcing that it is all in my head, and that these are close friends, etc. Basically just positive thinking.

4. Affects my sleep. I notice much less dreaming when smoking regularly. This is probably my greatest concern when considering the potential harms of indulging in this plant's fruits. I am worried about memory formation, circadian rhythm, etc.

5. Doesn't put me to sleep like most people, quite the opposite. If I smoke close to bed it will keep me up, as my brain is racing with random thoughts and new perspectives on issues I think about.

6. Kills motivation. Thankfully due to my inability to be at all social whilst under the influence, I have been unable to ever develop a serious Marijuana habit (I could never smoke before work, university, dinner at a friends house, etc). However during the few periods on my life when I was smoking daily (at night) I certainty noticed a decreased desire to basically just get shit done! Very influencing to staying in doors, playing games, watching movies, browsing the web, etc. Certainly was the time in my life when I exercised the least!
6.1 Side note, stretching under the influence of Marijuana is great. I always hated stretching but noticed a much higher tolerance of holding stretches whilst stoned.

7. I have never noticed any "bongover" or brain fog after smoking Marijuana. I have had many clear transitions between smoking regularly and complete abstinence and have never noticed any difference in the following day. Any effect is pale in significance to sleep quality (including amount), diet and exercise.

8. The huge variance in how it effects different people. I have great friends who are very similar to myself interms of interests and outlooks on life, social circles, grew up together, etc and they are profoundly different to myself under the influence, most notably in the social aspect. Like some posters have mentioned, I have friends who view Marijuana as a social lubricant akin to Alcohol. To me the difference could not be any more dramatic.
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#18 chris w

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Posted 01 September 2010 - 03:14 PM

Almost +1 with the above poster

Social interactions - bad, MJ in my eyes is ultimately a "solitary" drug ( unlike some alcohol used before socializing, that is by far the best lubricant to me ). After having smoked a little somethin somethin, the idea of going to a party and meeting some entirely new people that I would have to find things to talk about with, just freaks me out and wraps me into a cocoon in the basement.

Intelectual and sensual insight - definitely yes, I like reading on a mild high ; music, movies - greater esthetic appreciation of stuff, a walk in the afternoon sun through the neighbourhood feels like a foreign journey.

Motivation - For the first 1 or 2 hours it actually increases, I ocassionaly do moderate weight lifting then, if I have to write some paper for a college class, then this is the sweet spot to do this, after that comes the inevitable burnout and subsequent joints sometimes get me back to this state, sometimes only slow me down further.
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#19 medievil

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Posted 01 September 2010 - 06:39 PM

Couple study's on cannabinoids and memory and the mechanisms behind it.

The acute effects of cannabinoids on memory in humans: a review
by
Ranganathan M, D'Souza DC.
Schizophrenia Biological Research Center,
VA Connecticut Healthcare System,
West-Haven, CT, USA.
Psychopharmacology (Berl). 2006 Nov;188(4):425-44.

ABSTRACT

RATIONALE: Cannabis is one of the most frequently used substances. Cannabis and its constituent cannabinoids are known to impair several aspects of cognitive function, with the most robust effects on short-term episodic and working memory in humans. A large body of the work in this area occurred in the 1970s before the discovery of cannabinoid receptors. Recent advances in the knowledge of cannabinoid receptors' function have rekindled interest in examining effects of exogenous cannabinoids on memory and in understanding the mechanism of these effects. OBJECTIVE: The literature about the acute effects of cannabinoids on memory tasks in humans is reviewed. The limitations of the human literature including issues of dose, route of administration, small sample sizes, sample selection, effects of other drug use, tolerance and dependence to cannabinoids, and the timing and sensitivity of psychological tests are discussed. Finally, the human literature is discussed against the backdrop of preclinical findings. RESULTS: Acute administration of Delta-9-THC transiently impairs immediate and delayed free recall of information presented after, but not before, drug administration in a dose- and delay-dependent manner. In particular, cannabinoids increase intrusion errors. These effects are more robust with the inhaled and intravenous route and correspond to peak drug levels. CONCLUSIONS: This profile of effects suggests that cannabinoids impair all stages of memory including encoding, consolidation, and retrieval. Several mechanisms, including effects on long-term potentiation and long-term depression and the inhibition of neurotransmitter (GABA, glutamate, acetyl choline, dopamine) release, have been implicated in the amnestic effects of cannabinoids. Future research in humans is necessary to characterize the neuroanatomical and neurochemical basis of the memory impairing effects of cannabinoids, to dissect out their effects on the various stages of memory and to bridge the expanding gap between the humans and preclinical literature.

Cannabinoid-induced working memory impairment is reversed by a second generation cholinesterase inhibitor in rats
by
Braida D, Sala M
Department of Pharmacology,
Chemotherapy and Medical Toxicology,
University of Milan, Italy.
Neuroreport 2000 Jun 26; 11(9):2025-9

ABSTRACT

Cannabinoids which impair rat working memory appear to inhibit hippocampal extracellular acetylcholine (Ach) release and reduce choline uptake through an interaction with CB1 cannabinoid receptors. Here we report that CP 55,940, a potent bicyclic synthetic cannabinoid analog, dose-dependently impaired rat performance, when given i.p. 20 min before an eight-arm radial maze test. The selective CB1 cannabinoid receptor antagonist SR 141716A, given i.p. 20 min earlier, significantly reduced the memory deficit Pretreatment with eptastigmine, a second generation cholinesterase inhibitor, given orally 100 min before the cannabinoid agonist, relieved the memory impairment without affecting CP 55,940-induced behavioural alterations such as reduced spontaneous motor activity, analgesia and hind limb splaying. These data suggest that cannabinoid-induced working memory impairment is mediated through a central cholinergic blockade.

Cellular and molecular mechanisms underlying learning
and memory impairments produced by cannabinoids
by
Sullivan JM Molecular Neurobiology Laboratory,
The Salk Institute,
La Jolla,
California 92037, USA.
janes@AXP2.Salk.edu
Learn Mem 2000 May-Jun;7(3):132-9

ABSTRACT

Why does smoking marijuana impair learning and memory? Behavioral studies suggest that a disruption of normal hippocampal function contributes to these deficits. In vitro experiments find that cannabinoid receptor activation reduces neurotransmitter release below the levels required to trigger long-term changes in synaptic strength in the hippocampus. Cannabinoids reduce glutamate release through a G-protein-mediated inhibition of the calcium channels responsible for neurotransmitter release from hippocampal neurons. These mechanisms likely play a role in the learning and memory impairments produced by cannabinoids and by endogenous cannabinoid receptor ligands.


It can enhance creativity (and have some utility in some ADHD patients) but shouldnt be called a nootropic at all.

First study says it all.

CONCLUSIONS: This profile of effects suggests that cannabinoids impair all stages of memory including encoding, consolidation, and retrieval


Edited by medievil, 01 September 2010 - 06:42 PM.

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#20 kassem23

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Posted 01 September 2010 - 08:27 PM

My short-term memory is completely gone on MJ -- I can't formulate proper sentences, I lose track of conversations and I just want to relax -- because it can be quite frightening at times.

#21 k10

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Posted 03 September 2010 - 05:08 AM

A 2002 longitudinal study published in the Canadian Medical Association Journal concluded that "marijuana does not have a long-term negative impact on global intelligence", and that "current marijuana use had a negative effect on global IQ score only in subjects who smoked 5 or more joints per week." The study, which monitored subjects since birth, examined IQ scores before, during and after cessation of regular marijuana use. It found current light users and former users showed average IQ gains of 5.8 and 3.5 respectively, compared to an IQ gain of 2.6 for those who had never used cannabis.[79] The study did however show an average IQ decrease of 4.1 for heavy users.[79]

Edited by k10, 03 September 2010 - 05:09 AM.

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#22 NR2(x)

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Posted 03 September 2010 - 05:11 AM

That would fit with my own subjective experiences and observations of others

#23 Pike

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Posted 03 September 2010 - 06:41 AM

A 2002 longitudinal study published in the Canadian Medical Association Journal concluded that "marijuana does not have a long-term negative impact on global intelligence", and that "current marijuana use had a negative effect on global IQ score only in subjects who smoked 5 or more joints per week." The study, which monitored subjects since birth, examined IQ scores before, during and after cessation of regular marijuana use. It found current light users and former users showed average IQ gains of 5.8 and 3.5 respectively, compared to an IQ gain of 2.6 for those who had never used cannabis.[79] The study did however show an average IQ decrease of 4.1 for heavy users.[79]


the problem with that is that what that study found is only a correlation, and correlation does not prove causation. all one could say by reading that is that people who tend to very sparingly use or decided to quit have a tendency to develop a better learning ability. there could have been any number of other reasons that those occurred. it could happen to be just that the people who have it in them to quit smoking marijuana or decide that it's not something to be made a habit of are naturally the kinds of people who develop a higher learning ability later in life.

bottom line: correlation =/= causation.

Edited by Pike, 03 September 2010 - 06:42 AM.


#24 e Volution

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Posted 03 September 2010 - 07:02 AM

the problem with that is that what that study found is only a correlation, and correlation does not prove causation. all one could say by reading that is that people who tend to very sparingly use or decided to quit have a tendency to develop a better learning ability. there could have been any number of other reasons that those occurred. it could happen to be just that the people who have it in them to quit smoking marijuana or decide that it's not something to be made a habit of are naturally the kinds of people who develop a higher learning ability later in life.

bottom line: correlation =/= causation.

This is such an awesome example of the confirmation bias, normally I am making the same arguments for observational studies, this time round I am thinking but the interpreted results are the most likely scenario rather than some other confounding variables screwing up correlation! When we have observational studies like this, and where a controlled experiment is never going to be feasible, how do we then further investigate the correlation != causation issue? Or you just simply can not?

#25 NR2(x)

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Posted 03 September 2010 - 07:34 AM

This science has been conducted fairly well as it monitors the change in IQ that occurs from before the habit is picked up. This eliminates type one errors, which is pretty important. Think you need a rationale on this one for how correlation doesnt prove causation

#26 John Barleycorn

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Posted 03 September 2010 - 07:51 AM

The big thing you would want to control for is age of starting smoking. Starting pre full development is reputedly not good. Other obvious controls (really, covariates) would be duration of smoking, and initial IQ.

#27 maxwatt

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Posted 03 September 2010 - 11:40 AM

Ive read that certain people with ADHD find MJ therapeutic, not in my case, more like the opposite, but it does have therapeutic potential for some, but i agree that for most it will just be a dumb drug.


It would help me to see a citation for that.

#28 medievil

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Posted 03 September 2010 - 11:55 AM

Ive read that certain people with ADHD find MJ therapeutic, not in my case, more like the opposite, but it does have therapeutic potential for some, but i agree that for most it will just be a dumb drug.


It would help me to see a citation for that.

I dont have a citation as its just anecdotal.

Re: long term toxiticy of MJ, i'm pretty sure that study was also included in my attachment wich reviewed all of the evidence around that time, not sure tough was long ago ive read the paper but it its a very good overview.

Edited by medievil, 03 September 2010 - 11:55 AM.


#29 gamesguru

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Posted 04 September 2010 - 06:33 PM

You can't directly compare the amount you vaporise with the amount that would be in a joint since combustion is a far less efficient way of delivering the actives to a user. But getting buzzed twice a day? I would consider that moderate-heavy.

I agree, the percentage of THC removed from the plant material will be a dependent variable upon the method of ingestion.

I would not agree with this statement. Twice a day consumption of cannabinoids can be of great therapeutic benefit, but that is all contingent upon the dose per use. At a qualitatively low dose, for me at least, and potentially everyone if I possess no genetic anomalies of cannabinoid receptor spatial density, none of the memory impairment- or learning down-regulation-related symptoms manifest themselves. It is only at the qualitatively high doses (to whom I mentioned again) where the individual experiences lasting impairment of memory formation and learning.

Given this, using small doses of cannabinoids twice daily is of no burden to cognitive function and as such is true, I would not consider that "moderate-heavy". I have known many researchers at my university (I work in the theoretical physics department conducting research on theoretical quantum magnetism) who use cannabinoids twice daily at low doses and, even in one of the most intellectually-demanding jobs known to man, experience no decline in productivity and therefore no learning impairment. They cannot be differentiated from the non-users only on the basis of their productivity and intellectual function. Now I have also known very many researchers (typically new college students who have no maturity in their behavior) who have used cannabinoids twice daily at HIGH DOSES who have also lost their jobs based on my testimonies to the physics dept. head suggesting they had an extreme lack of productivity and a deficiency in learning rates.

Now certainly, my sample size is small. Put together, only about 5 people from each side, it is very small. But I see no reason to doubt my instinctual intuition which has guided me towards this belief based solely on the data I have seen in my life. It seems to be a very general phenomenon amongst adolescents. Those who learn how to use it find it useful, those who learn not how to use it find it a burden.
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#30 bobman

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Posted 06 September 2010 - 08:54 AM

Definitely nootropic for me, the effect lasts at least to the next day, although I've noticed that at times a single experience would create a "turning point" in my cognition, a permanent change, and so far positive every time. I smoke to deepen an introverted, meditative experience, and it definitely helps my mind broaden and synchronize to better track new ideas of the highly divergent type leading to widely sampled congruency.
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