39 replies to this topic

[B!oN!cSy@PsE]

Hello, I am Final Year Medical Student With nootropic experience of 5 years. I will try to Give you better idea about nootropics and brain/body. Of course it will be considered a hypothesis.

1.BRAIN & INTELLIGENCE:
Intelligence is a wide term which can be tough to explain so I will rather try to explain why you are what you are.
-Genes- of course the most important of all. They determine how the stock model of brain will be and they also determine how far your brain can go positively as well as negatively.
-Environment- This is 2nd most important. If albert einstein was put into a jungle since his childhood with no communication with other humans he wouldnt be the great einstein that we know inspite of having genetic capacity. PTSD( post traumatic stress disorder) is another example of how your brain can be messed up even if you had genes to be genius.
-nutrition, habits, lifestyle- Its a simple fact that it is very difficult to build something and very easy to destroy it. Our body has powers to get rebuilt from all the damages happened from trauma, poor nutrition or other cause but to a extent. the more severe the damage the less chances of recovery naturally.
I will end this section here because it will be off topic.

2.NOOTROPICS:

I would like to give answer of question that why nootropics have different effects in every person.

2A. PHARMACOLOGICAL ASPECTS- this applies to all the drugs or exogenous substance administered in body.
-Pharmacokinetics, Pharmacodynemics, absorption, excretion etc for a particular compound will be different in every person to a some extent. This aspects affect that how long the molecule you administered stay in ur brain and in what concentration. This will have direct effect on the effect produced by a molecule in a person.

2B. GENETIC VARIATION-
-genes have great influence on size and structure of your brain, numbers of neurotransmitter receptors and many other things. So when you are giving a particular substance to a person and noticing the effect produced by it, it will be wrong to call it effect of that substance but it will be effect of that substance + your present brain condition which is firstly determined by genes and secondly by other factors like environment, nutrition, habits etc..... But most of us has similar brains in structures yet they are different just like everyone has nose, eyes, ear, mouth and they perform same functions in everyone yet they are somewhat different in looks and efficiency of function performed by them in every person.
So clinical trails are just like pointing out that eyes serves visual function in humans but everyone's vision is a bit different including & excluding the various pathology of eyes. In same way clinical trails can point of primary function of particular substance but yet it will be different in each n every person.

2C. PSYCHOLOGICAL ASPECTS-
We cant think that when we administer a nootropic it affects those receptors and/or neurotransmitter according to its mechanism of action while your whole cns process is frozen or nil. It means Nootropic is not the only thing affecting your neurotransmission when you take it, behaviors. actions, thinking etc everything has effect on your neurotransmission. There has been studies out there which already state that same dose of amphetamine has different reinforcing effects according to environment. If you travel to novel environment at the same dose that you used to take, that novel environment will increase reinforcing effect of same dose twice or thrice. So whether you increased the dose or traveled to a novel environment both has same effects on your brain.
So basically your habits, current mood state and thinking will have direct positive or negative effects on the nootropic that you took. your some mood state will boost effects of nootropics while some will decrease its effects.
Thats why same nootropic has different effects. This also applies to tolerance where drug loses its effect, may be the drug alone never had that powerful effect, that effect was combination of drug+ something that you were doing that was augmenting the effects of drug and you stopped doing it. So you will feel that you got tolerant to nootropic's effect.

I wish I could write more but running out of time for now. I will continue according to time I get. I have a lot to write yet.

[chung_pao]

Getting through medical school, what nootropics has been of most use to you?

"I would like to give answer of question that why nootropics have different effects in every person."

What is the relationship between acetylcholine and the catecholamines? Does choline depletion cause or contribute to mania?
Just giving you something more specific to work on mate.

Edited by chung_pao, 07 February 2013 - 07:40 PM.

[peakplasma]

I'm sorry but these are all literally cliches!!!!

None of your points offer a new perspective and most of them have been discussed ad nauseum.

For example, the psychological aspects or "set and setting" have been actively discussed since at least the 1960's in the context of bad trips with psychedelics. Same goes for your first point... "nature vs nurture" said everyone whose taken Psych-101!

I think you are underestimating the knowledge on this forum; some of us have more than a few years in med school to boast about.

If you want to make a contribution, I would encourage you to capitalize on your school's access to resources. For example, almost everyday someone requests a full version of a paywalled article.

Edited by peakplasma, 07 February 2013 - 07:47 PM.

[B!oN!cSy@PsE]

Getting through medical school, what nootropics has been of most use to you?

"I would like to give answer of question that why nootropics have different effects in every person."

What is the relationship between acetylcholine and the catecholamines? Does choline depletion cause or contribute to mania?
Just giving you something more specific to work on mate.

Before I answer anything Let me make this thing clear, We are in no position to know every mechanism and aspects of our brain for now, because it will be somewhat different in every person. All we have is hypothesis. Something that works wonders for one might not be of any wonder for other. Least we can do is trial and error to find your own wonder. if it is wonder then how long that wonder will last, what will it do to you in future good/bad is also inconclusive. But if you have decided to take nootropics then I guess its the risk everyone here is willing to take.
Coming back to your question. The nootropics which has been most useful to me wont help you much because buying and taking nootropics is not enough, there is a lot of side job which I will discuss here later.
Acetylcholine and dopamine connection is most prominent. then comes acetylcholine and norepinephrine connection. And it will affect every neurotransmitter because all the neurotransmitter systems are interconnected, When you increase level of one neurotransmitter it will have effect on levels of all neurotransmitter to more or less extent. Recently Hyperactivity of muscarinic acetylcholine receptors has been shown to produce negative symptoms of schizophrenia which includes apathy, amotivation, emotional numbing, social isolation, anhedonia. if you look opposite to this then blockade of muscarinic receptors has been shown to produce euphoria and antidepressant effects which depends on strength and duration of block. On other hand activation of nicotinic acetylcholine receptors is associated with release of NE and DA. but acetylcholine has less affinity for nicotinic receptors compared to muscarinic receptors. So if levels of acetylcholine are increased in brain then first it will saturate binding with muscarinic receptors and then it will bind nicotinic receptors. so blocking of muscarinic receptors will also lead to increase binding of acetylcholine to nicotinic receptors because it cannot bind to muscarinic receptors due to block, this will lead to increased levels of NE and DA through nicotinic receptors.
Now question is whether choline or acetylcholine depletion is possible in normal circumstances? amphetamine is well known depletor of dopamine but whether racetams does same to acetylcholine is a question. and choline is also independently present in brain along with acetylcholine. Theoretically depletion of acetylcholine can reduce muscarinic receptor activation which can have somewhat good effects on mood but not comparable to anticholinergic euphoria becaue if acetylcholine is depleted it will also reduce nicotinic receptor activation which will be reduced DA and NE release.
If acetylcholine and catecholamine have inhibitory effect on eachother then the person who is having amphetamine crash mush have brilliant long term memory recall during his crash period.
So choline depletion has somewhat boosting effect on catecholamine by removing muscarinic receptor inhibition but it cant boost it to a level where it can produce mania unless you have bipolar disorder or some other disorder where sensitivity of your receptors keep fluctuating. Still it is not enough to be conclusive, but since choline depletion can increase catecholamine effects there is potential for mania but very less.

[CrazyIguana]

genes have great influence on size and structure of your brain

I would like to point out that the size of your brain has nothing to do with performance, while structure is another story.

[B!oN!cSy@PsE]

I'm sorry but these are all literally cliches!!!!

None of your points offer a new perspective and most of them have been discussed ad nauseum.

For example, the psychological aspects or "set and setting" have been actively discussed since at least the 1960's in the context of bad trips with psychedelics. Same goes for your first point... "nature vs nurture" said everyone whose taken Psych-101!

I think you are underestimating the knowledge on this forum; some of us have more than a few years in med school to boast about.

If you want to make a contribution, I would encourage you to capitalize on your school's access to resources. For example, almost everyday someone requests a full version of a paywalled article.

I wrote that I am medical student because I hardly post something here so letting everyone know about my medical background might make people at least read the post. I am not proud or boasting about it, In fact I feel opposite way because medical knowledge still is so much backward that even after so many years of human birth we still can't understand everything about our body and brain. Yes, Its obvious that I cant be the first one to think about all this aspects that I wrote here. It is just conclusion of what I learned, read and experienced till now with no intention of claiming my superiority of knowledge. I am just trying to show best way out of nootropics and to do that, reading all this is necessary first. Oh sorry not the best way I should say a good way otherwise few other people will post their thread links of their best ways. I am just sharing whatever good I can, it may help you or it may not. My intention is to help, I wont ask anything in return. I will see if I can do something about that abstract request thing,

[LBGSHI]

genes have great influence on size and structure of your brain

I would like to point out that the size of your brain has nothing to do with performance, while structure is another story.

Incorrect; brain size is a significant factor in intelligence (along with convolutions and complexity, as you allude to). For example:

http://en.wikipedia....lligence#Humans - Brain size, Humans

http://www.ncbi.nlm....pubmed/20072853 - Genetic covariation between brain volumes and IQ, reading performance, and processing speed

http://www.sciencedi...160289691900318 - In vivo brain size and intelligence

http://onlinelibrary...400314/abstract - Brain size and intelligence in man

...and so on.

[CrazyIguana]

genes have great influence on size and structure of your brain

I would like to point out that the size of your brain has nothing to do with performance, while structure is another story.

Incorrect; brain size is a significant factor in intelligence (along with convolutions and complexity, as you allude to). For example:

http://en.wikipedia....lligence#Humans - Brain size, Humans

http://www.ncbi.nlm....pubmed/20072853 - Genetic covariation between brain volumes and IQ, reading performance, and processing speed

http://www.sciencedi...160289691900318 - In vivo brain size and intelligence

http://onlinelibrary...400314/abstract - Brain size and intelligence in man

...and so on.

There is a difference between the SIZE of the brain and the Neuronal Count of the brain. My point is, density is what actually matters, not size. Larger brain size decreases density which leads to lower connection count (think about it, longer distances for connections will result in less of them).... and so on. This is why I said that the structure of the brain is really what matters more.

If you recall, one of the arguably smartest and definitely most influential members of modern society, Albert Einstein, did not have a large brain, in fact is was considered to be on the mid-lower end of the average brain size scale.

[jadamgo]

None of your points offer a new perspective and most of them have been discussed ad nauseum.

{...}

I think you are underestimating the knowledge on this forum; some of us have more than a few years in med school to boast about.

Look how many posts are made by newbs asking the same questions over and over again. Every day. Wouldn't you like to have a comprehensive collection of the knowledge we already have, so you could link those newbs to it instead of having to discuss their questions ad nauseam?

[LBGSHI]

There is a difference between the SIZE of the brain and the Neuronal Count of the brain. My point is, density is what actually matters, not size.

But your point is wrong. Both brain size and complexity are important. A tiny brain with high complexity would still not yield the processing capability of a large brain with high complexity. You're claiming that size is irrelevant, which is simply incorrect.

Larger brain size decreases density which leads to lower connection count (think about it, longer distances for connections will result in less of them)....

This isn't how the brain works. If this were the case, larger brains wouldn't correlate with higher intelligence - yet they do.

If you recall, one of the arguably smartest and definitely most influential members of modern society, Albert Einstein, did not have a large brain, in fact is was considered to be on the mid-lower end of the average brain size scale.

Yes; Einstein's brain was slightly smaller than average, yet highly complex, with a higher proportion of glial cells than the average brain (though that finding is debatable), and several other peculiarities. However, despite Einstein's pseudo-celebrity status, it should be kept in mind that he is one of many brilliant people, and that he is not likely the most intelligent person we've ever had. The vast majority of brains measured did show a positive correlation between size and intelligence.

[alexburke]

http://www.pbs.org/w...pigenetics.html

Look up epigenetics.. Anyone can learn to become intelligent, its called neuroplasticity.
School systems outdated anyways..

[CrazyIguana]

Ok, I will accept that there may be a weak correlation (.3 from most studies). Even from a high school Statistics class, it's generally accepted that r = .3 (r² = .09, which suggests that the correlation isn't one on which you can trust) is a weak correlation, and by no means provides evidence for cause and effect. It may be so that 9% of people with bigger brains are smarter (r² indicates this). That is the only conclusion you can draw from any of the experiments you linked. While I am not saying there is no connection, I'm saying there is a weak connection between brain size and intelligence.

That being said, from a statistical view point, of which science validates its claims, instead of "brain size is a significant factor in intelligence" it should be, brain size is a weak factor in intelligence.


And to be fair, when I said that brain size has nothing to do with performance, the correct observation should be, brain size has almost nothing to do with performance.

http://www.bized.co....relate_expl.htm

Here's a good question to ask yourself: Would you bet $100 with odds like 9%? If not, then I wouldn't bet the studies are correct if I were you.

Edited by CrazyIguana, 08 February 2013 - 12:03 AM.

[B!oN!cSy@PsE]

Ok, I will accept that there may be a weak correlation (.3 from most studies). Even from a high school Statistics class, it's generally accepted that r = .3 (r² = .09, which suggests that the correlation isn't one on which you can trust) is a weak correlation, and by no means provides evidence for cause and effect. It may be so that 9% of people with bigger brains are smarter (r² indicates this). That is the only conclusion you can draw from any of the experiments you linked. While I am not saying there is no connection, I'm saying there is a weak connection between brain size and intelligence.

That being said, from a statistical view point, of which science validates its claims, instead of "brain size is a significant factor in intelligence" it should be, brain size is a weak factor in intelligence.


And to be fair, when I said that brain size has nothing to do with performance, the correct observation should be, brain size has almost nothing to do with performance.

http://www.bized.co....relate_expl.htm

Here's a good question to ask yourself: Would you bet $100 with odds like 9%? If not, then I wouldn't bet the studies are correct if I were you.

Brain size and structure has effects on nootropics taken. thats the only thing to point out. To a what extent is not something to be focused on rightnow. For Example brain size and structures are like your computer hardware and nootropics are like software. Performance of software will definitely depend on your hardware. And that neurogenesis, neuroplasticity, incidence where thickness of cortex or other area of brain is increased is just like overclocking your hardware but still it will be just modification to some extent, it will be wrong to call it a new hardware. Child prodigy is best way to see the power of genes.

[B!oN!cSy@PsE]

TYPES OF NOOTROPIC EFFECTS

There are mainly three types of nootropic effects observed according to what you are taking.

1. feeling Intelligent
2. Being Intelligent
3. Preserving intelligence

1.Feeling Intelligent. -

This is mostly dopaminergic phenomenon, commonly seen with stimulants. Where they amplify the perception of achievement, For Example even if you solved an easy riddle, person under influence of stimulant will feel they just cracked the most difficult riddle. No matter how much they actually got benefited from stimulants, most of users will feel they got significant benefits.
But this effect is beneficial indirectly because when you get amplified feelings of achievement it will have positive influence on your further achievements, making you better day by day because you are going through various cognitively demanding tasks where stimulants gives you strength to stay on that task.
Another advantage is sometimes many people have potential to achieve something but if they are not feeling confident, they have no motivation, drive etc then their potential will remain unused.
Initially, stimulants will improve your reaction speed, alertness, motivation etc but with chronic use tolerance is an issue. Achieving homeostasis with stimulants is necessary to prevent going towards addiction and to continue getting beneficial effects with a reasonable level of tolerance.

2.Being Intelligent -

This are the compounds which actually increase your intelligence But it is hard for you to notice it without going through cognitive tests. There is also limitation in this field of nootropics as compounds available rightnow can increase intelligence only to a minor extent that wont have big impact on your life.
But their effect are quite noticeable in person having various brain pathology and disorders. but it also depends on type of pathology or disorder. They are most likely to work best if you acquired cognitive impairments during your life, if thats the case then these type of nootropics can bring back to your baseline level again. but if you are already at baseline they won't make a drastic change.
Memory is only aspect of intelligence that can be enhanced noticeably compared to other aspects of intelligence with current nootropic compounds.

3.Preserving Intelligence-
This are compounds which mainly keep you at your baseline or achieved level and mainly prevent the cognitive deterioration. neuroprotective substances, vitamins, minerals, exercise etc. In general all the compounds that protects you from deteriorating.

[B!oN!cSy@PsE]

NOOTROPICS EFFECT & TARGET EFFECT

When You take a nootropic to get benefit in particular task or field is of unpredictable outcome. You cant pop a dexedrine pill and tell it that increase my attention in studies for next 5 hours. When it can make a boring book more interesting then it can definitely make already interesting things almost irresistible. When you decided that you will read after taking dexedrine was a different mind state and your mind state will be different under the influence of dexedrine. So nootropic effect of increased attention is obtained when you take dexedrine but target effect which is increase attention in studies may not be necessarily obtained.
drugs which increase your thinking capacity also has somewhat above mentioned same effect. You take something to increase your thinking and understanding power so that you can understand topics and things faster in your school but again when you are able to think better you are in different mind state than before. It is possible that you may start thinking that school system is useless, You could give your time to more useful things and you lose interest in school. If you see the past record, most of extraordinary geniuses were average in their school or collage dropouts. So again nootropic effect which is increase thinking capacity is present but target effect which is increase performance in school may not be necessarily achieved by it.

[B!oN!cSy@PsE]

NOOTROPIC EFFECTS & CHOICE OF COGNITIVE ASPECT

No man can be a creative genius, at the same time with having great longterm memory, pro social life, great attention span. Because those extreme cognitive states are outcome of dominance of one particular brain region or neurotransmission cascade which will give unhuman abilities in one aspect of cognition where as below average performance in other aspects of cognition.
Stimulants will increase your motivation and attention as well as short term memory. But at the cost of compromising long term memory recall. Higher the dose of stimulant the more impaired long term recall will get. especially if something is making you euphoric, it will impair your long term memory recall. because of balance between acetylcholine and dopamine. euphoria is high dopamine which will suppress effects of acetylcholine vice versa.. This view is also compatible with cognitive impairment seen in case of mania in bipolar disorder. A maniac person will have godlike confidence, he requires less sleep, he is very energetic. Somewhat someone being high on stimulants.
on opposite side, many people report getting depressed after then take acetylcholine esterase inhibitors or high dose of choline or drugs which increase acetylcholine levels. They will have great long term memory recall but at cost of mood, motivation and somewhat attention.
As far as schools are concerned you need to stay in a balanced condition because if you go to extreme in one thing you will get impaired in the other and in school all the aspects are equally important, that is why it is most difficult thing to create a nootropic stack for collage or school.

[B!oN!cSy@PsE]

NOOTROPICS & TOLERANCE

First of all I will discuss about most commonly discussed tolerance, The Stimulant Tolerance. I will use non neurological examples to explains it because neuropharmacology dosent give perfect answer in this case.
I will give example of music. Music is ofcourse one of the strongest natural reinforcers after sex. Ok So you started liking a song which gave you intense pleasurable feelings. What will happen if you listen to same song repeatedly? Soon enough you will reach to a point where listening to that song will give you boredom instead of pleasure. So did that music downregulated your dopamine receptors or produce toxicity? Most probably that cannot happen. So why you lost those pleasurable effects? its the memory. As soon as the memory of a particular stimulus reach certain level of consolidation your brain will stop giving dopaminergic pleasure response either by inhibiting its release or by increasing the effects of other neurotransmitter which can have inhibitory effect on dopamine. (acetylcholine or glutamate most likely)
now what will happen if you hit your head somewhere which produced temporary amnesia and you forgot the memories of that song. if you listen to that song again and start liking it, it is possible that you may get pleasurable effects once again.
in other case, you shifted to other song of your liking and after few days you came back to your old song then your old song will be again pleasurable but not as much as you listen to it first time.
Motivation cannot come without presence of reinforcement, and motivation has direct effect on your attention quality and attention span, Isn't this the primary effect of all stimulants?
now there are many evidence that NMDA receptors play important role in memory and learning. blocking it will reduce the learned tolerance to stimulant's effect. but how can you expect that erasing stimulant's effect will not erase what you read or learned under the influence of stimulants? as in above example, Amnesia may bring back responsiveness of your song but we should not forget that amnesia also made you forget about song lyrics and every detail of it. so when you use NMDA antagonist with stimulant, you may get stimulant's effect back because you forgot the previous effects of stimulants but you may also have forgotten everything you read while you were on stimulant. this effect wont bother much to people who just wanna have good times with help of stimulants but a person preparing for school or collage test will be adversely affected by this.

[B!oN!cSy@PsE]

Task-specific tolerance to d-amphetamine.

Emmett-Oglesby MW, Spencer DG Jr, Wood DM, Lal H.

Abstract


Rats were trained concurrently on sweetened-milk drinking and bar-press-responding behavior, which alternated on a daily basis. Dose-response functions for d-amphetamine were determined before and after conditions of chronic treatment. When given before chronic treatment, d-amphetamine decreased both milk consumption and reinforcement received for lever-pressing in a dose-dependent manner. Subsequently, three conditions of chronic injection were established in which one group received saline, prior to both tasks, another group received d-amphetamine prior to drinking milk and saline prior to lever-pressing and the third group received d-amphetamine prior to lever-pressing and saline before drinking milk. The rats became tolerant to d-amphetamine in the task in which the drug had been administered chronically; however, the same rats showed no tolerance in the other task in which saline had been administered chronically. Tolerance to d-amphetamine was thus shown to be behaviorally specific.

So Either change your task or take NMDA antagonist to erase the memory of the task you did can bring back effects of stimulant once again.

[B!oN!cSy@PsE]

The reason why some people with ADHD continue to get benefits from stimulants for long time without tolerance is because reward system is different in ADHD person compared to normal person. So exposure to stimulus, reinforcement, memory consolidation etc must be different in them compared to normal person. But some many people who have ADHD also develope tolerance, in that case may be they were misdiagnosed or protection from tolerance is only limited to one specific type of ADHD.
As tolerance to stimulants is task specific, we can tweak the way in which stimuli is presented to our brain to get the effects of stimulants back. For example, if you used to read silently, start reading loudly thus the same information will now get presented along with auditory input and your brain will interpret it differently. same thing with environment, changing your reading place frequently will increase responsiveness of stimulants. cycling between these things may allow you to achieve benefits from stimulants to a reasonable level without erasing what you learned.

[B!oN!cSy@PsE]

Stimulants are no magic pills. You have to use approach that you use for other things in your daily life to keep continue getting benefits. Your girlfriend might be the most attractive woman on earth but after some time she will not feel as attractive as she used to be. So would you hit your head to get amnesia just to make your gf feel attractive once again? or you would suggest her to try different clothing, makeup, or lifestyle change to bring back that feeling of attractiveness? This is the only way to get maximum out of stimulants otherwise they will do more harm than benefit.

[LBGSHI]

Ok, I will accept that there may be a weak correlation (.3 from most studies). Even from a high school Statistics class, it's generally accepted that r = .3 (r² = .09, which suggests that the correlation isn't one on which you can trust) is a weak correlation, and by no means provides evidence for cause and effect. It may be so that 9% of people with bigger brains are smarter (r² indicates this). That is the only conclusion you can draw from any of the experiments you linked. While I am not saying there is no connection, I'm saying there is a weak connection between brain size and intelligence.

That being said, from a statistical view point, of which science validates its claims, instead of "brain size is a significant factor in intelligence" it should be, brain size is a weak factor in intelligence.


And to be fair, when I said that brain size has nothing to do with performance, the correct observation should be, brain size has almost nothing to do with performance.

http://www.bized.co....relate_expl.htm

Here's a good question to ask yourself: Would you bet $100 with odds like 9%? If not, then I wouldn't bet the studies are correct if I were you.

.3x correlation was derived by cranial measurement (a stupid way to measure brain size accurately). Brain scans and direct brain measurement provide an average of .4 correlation, which is to say a 16% correlation (for example, http://www.ncbi.nlm....pubmed/19283594). Incidentally, the Pearson's scale, which is what we're using to refer to correlation in this sense, places 0.4 exactly between medium and large correlation (http://en.wikipedia....8correlation.29). More pertinently, the correlation is much higher when measuring specific abilities than general IQ tests:

http://www.ncbi.nlm....pubmed/20072853:

Although there has been much interest in the relation between brain size and cognition, few studies have investigated this relation within a genetic framework and fewer still in non-adult samples. We analyzed the genetic and environmental covariance between structural MRI data from four brain regions (total brain volume, neocortex, white matter, and prefrontal cortex), and four cognitive measures (verbal IQ (VIQ), performance IQ (PIQ), reading ability, and processing speed), in a sample of 41 MZ twin pairs and 30 same-sex DZ twin pairs (mean age at cognitive test = 11.4 years; mean age at scan = 15.4 years). Multivariate Cholesky decompositions were performed with each brain volume measure entered first, followed by the four cognitive measures. Consistent with previous research, each brain and cognitive measure was found to be significantly heritable. The novel finding was the significant genetic but not environmental covariance between brain volumes and cognitive measures. Specifically, PIQ shared significant common genetic variance with all four measures of brain volume (r (g) = .58-.82). In contrast, VIQ shared significant genetic influence with neocortex volume only (r (g) = .58). Processing speed was significant with total brain volume (r (g) = .79), neocortex (r (g) = .64), and white matter (r (g) = .89), but not prefrontal cortex. The only brain measure to share genetic influence with reading was total brain volume (r (g) = .32), which also shared genetic influences with processing speed.

It would be foolish to discard brain complexity in favor of only brain size, but it would also be foolish to do the opposite.

[CrazyIguana]

.3x correlation was derived by cranial measurement (a stupid way to measure brain size accurately).

Then why did you cite it?

It would be foolish to discard brain complexity in favor of only brain size, but it would also be foolish to do the opposite.

I think we can both agree to this point, that there is more to intelligence than brain size.

[LBGSHI]

.3x correlation was derived by cranial measurement (a stupid way to measure brain size accurately).

Then why did you cite it?

Only one of the four references I cited mentioned the value 0.3; I was providing multiple citations from different sources to show that the correlation did exist. I didn't expect to debate about whether it was 0.3 or 0.4.

It would be foolish to discard brain complexity in favor of only brain size, but it would also be foolish to do the opposite.

I think we can both agree to this point, that there is more to intelligence than brain size.

Yes, as long as we can also agree that there is more to intelligence than brain complexity

[CrazyIguana]

Yes, as long as we can also agree that there is more to intelligence than brain complexity

And that I think we can.

[Daruman]

No offense to Saral Desai, but this isn't being productive. It reiterates essentially self explanatory information and by being watered down it is edging on being misinformation. There is plenty of resources for new members already. The only thing this is doing is adding buzzwords for Google.

I also don't believe your writing is on par with a medical student, it is just lazy.

[B!oN!cSy@PsE]

No offense to Saral Desai, but this isn't being productive. It reiterates essentially self explanatory information and by being watered down it is edging on being misinformation. There is plenty of resources for new members already. The only thing this is doing is adding buzzwords for Google.

I also don't believe your writing is on par with a medical student, it is just lazy.

Yes, Lack of time is the reason, It happens when you want to share information but don't have that much time to write it in professional way. Well, we have whole lot of research on neurology and nootropics but neuropharmacology doesn't necessarily give answer to all questions. If people were Actually getting what they wanted from nootropics then they would not be coming here that often. Luckily, I am one of them. No offence noted, You just saved me a lot of time because I will end the topic here. Have a nice day

[nootrope]

I think it's valuable to step back and look at the big picture, as the Topic Starter is doing here. A couple of people here seem annoyed and maybe that's because he touted his medical background and over-stated the novelty of his view. There may be a lot implicit in current research that could be ignored by focus on particular detailed results. For example, nature vs. nurture might be old hat, but the discoveries in epigenetics are fairly recent. It's worth pointing out how many-facted intelligence is and how many tradeoffs are involved in "improving intelligence." Sure, many or most posters may know this, but sometimes I get a sense of overconfidence from people who do a lot of reading that, for example, ingesting a certain substance will definitely lead to such and such a neurotransmitter being upregulated, and then we hear over-simplified stories of the roles of each--dopamine for pleasure/reward, serotonin and mood, acetylcholine and memory.

As far as brain size vs. intelligence, it's also worth noting that there are people with abnormalities that lead to their brains being greatly compressed against their skulls, and yet many such people have normal intelligence. People with tumors may have an entire hemisphere removed, and in many cases one hemisphere can duplicate the functions of the other, and some such people have normal intelligence. So if there's a correlation, that doesn't mean it's linear. Even some of those apparent mental advantages tested for may be double-edged swords. Processing speed? Obviously the brain is processing many different things at different levels. A person who takes longer to answer a question may get to take input from parts of the brain that a person who thinks quicker may not make use of. We all know people who are quick but glib, and people who are thoughtful but take a little longer to reach their conclusions.

[B!oN!cSy@PsE]

We Don't Want how many PubMed Abstracts you read, We don't want how skillful you are in cutting a new way with Abstract links, Because in the end your abstracts knowledge will fail to answer a simple question that why this nootropic doesn't work for me. Whoever Designed our brain was not some Rookie going through trial test, Its more complex than bunch of neurotransmitters and receptors. How many success stories are there who defeated the naturally gifted person with stacking all these nootropics? Quite few. If we keep playing games of respect and proving who has best knowledge then we are not progressing forward just fooling our minds. People run behind fame only when they are unsatisfied, try to prove their existence only when they don't have enough self esteem. And when we all know all these feelings are product of mind then its better to focus on the mystery of it rather than playing alpha-beta games on discussion boards. Troll me, Say something bad to me, say the sickest thing to me Or thank me, congratulate me, praise me, Nothing will matter to me because after struggling for many years I have achieved state of mind which is neither overconfident nor depressive, emotional but only when I want to, Logical but not imagination killer. How I achieved will not be a perfect guideline as it will not be a universally applicable. But again its not boasting about what I achieved, its to bring light on the fact that taking nootropics and doing nothing else is definitely not the way to get there. In fact the more you think about what you have taken and what you are getting as an effect will make effect of the same compound more complex. Remember Inception movie? where someone enters(nootrpic) into other's dream (your body), the dream will continue to flow good unless u arouse suspicion on that someone(nootrpic) and everyone in dream start staring at that someone as per movie. This one was funny example but It conveys the main point. I have nothing to gain or nothing to lose, It wont even matter if you make fun of this or take it seriously, but when you already tried so many things then leaving few things which are totally non of harm would be.........again its the choice that you make. I'll take your leave here.

[nupi]

Ok, I will accept that there may be a weak correlation (.3 from most studies). Even from a high school Statistics class, it's generally accepted that r = .3 (r² = .09, which suggests that the correlation isn't one on which you can trust) is a weak correlation, and by no means provides evidence for cause and effect. It may be so that 9% of people with bigger brains are smarter (r² indicates this).

Except that correlation and r2 never determine the least bit of causation... r=0.3 is not that bad given that we are looking at a highly multi variate system, BTW.

As for saral's post just above mine, that's just painful to read (not sure what it is trying to say, either). How about, you know, using paragraphs and maybe quickly glancing over what you wrote to fix at least the most egregious grammar mistakes? If you are going to claim authority from education (does not work for me, most doctors I are too bad at what they do for me to be impressed with that anymore), at least spend the time to prove you have it. If you lack the time, then don't boast about it.

Edited by nupi, 09 February 2013 - 01:04 PM.

[B!oN!cSy@PsE]

Placebo is the biggest example available in front of us since so long which shows that your thinking is powerful enough to make a change, giving piracetam to some illiterate and giving piracetam to a abstract geek who will think "I am taking piracetam, it will increase my memory and performance through positive modulation of NMDA receptor or increasing membrane fluidity or upregulating mitochondrial function." will have different effects.