This is not 100% clear from the data and just blindly using a plausible amount carries the risk of the negative effects, so I intend to run another large experiment. I will reuse the NOW Foods Magnesium Citrate Powder, but this time, I will use longer blocks (to make cumulative overdosing more evident) and try to avoid any doses >150mg of elemental magnesium.
Be patient.  Even though you may notice some improvements right away (sometimes within the first day), you should give your brain supplement at least several months to work.  The positive effects are cumulative, and most people do not max out their brain potential on a supplement until they have used it for at least 90 days.  That is when the really dramatic effects start kicking in!
A big part is that we are finally starting to apply complex systems science to psycho-neuro-pharmacology and a nootropic approach. The neural system is awesomely complex and old-fashioned reductionist science has a really hard time with complexity. Big companies spends hundreds of millions of dollars trying to separate the effects of just a single molecule from placebo – and nootropics invariably show up as “stacks” of many different ingredients (ours, Qualia , currently has 42 separate synergistic nootropics ingredients from alpha GPC to bacopa monnieri and L-theanine). That kind of complex, multi pathway input requires a different methodology to understand well that goes beyond simply what’s put in capsules.

“It is surprising and encouraging that it may be possible to predict the magnitude of a placebo effect before treatment,” says Tor Wager, a neuroscientist at the University of Colorado Boulder, who was not involved in the research. More work is needed to see how the predictive features hold up in other populations and for different pain conditions, he says.
Such competitive anxieties are already being felt in the workplace. Recently an advice column in Wired featured a question from a reader worried about "a rising star at the firm" who was "using unprescribed modafinil to work crazy hours. Our boss has started getting on my case for not being as productive." And on internet forums such as ImmInst (Immortality Institute), whose members share a nerdy passion for tweaking their cognitive function through drugs and supplements, people trade advice about dosages and "stacks" - improvised combinations - of neuroenhancers ("Cut a tablet into fourths and took 25mg every four hours, four times today, and had a great and productive day - with no side-effects"). In one recent post a 52-year-old - who was working full time, studying for an advanced degree at night and "married, etc" - wrote that after experimenting with modafinil he had settled on two daily doses of 100mg each. He believed that he was "performing a little better", adding: "I also feel slightly more animated when in discussion."
The nootropic sulbutiamine, of the synthetic B-vitamin-derived nootropics family, is generally considered a low-risk supplement; however, some users have reported that the supplement has addictive qualities. While there is no firm evidence of sulbutiamine addiction, the risk may increase at high dosages. For instance, users who consume this supplement for 10 consecutive days may experience withdrawal for two to five days. There are also increased risks when sulbutiamine is taken with antipsychotic medications.[8]
I eventually met Seltzer in an underground food court not far from the Pentagon. He's slim, with a shaved head, and he spoke precisely, rarely stumbling over his words. I asked him if he had any ethical worries about smart drugs. After a pause, he said that he might have a concern if somebody popped a neuroenhancer before taking a licensing exam that certified him as, say, a brain surgeon, and then stopped using the drug. Other than that he couldn't see a problem. He said that he was a firm believer in the idea that "we should have a fair degree of liberty to do with our bodies and our minds as we see fit, so long as it doesn't impinge on the basic rights, liberty and safety of others". He argued: "Why would you want an upward limit on the intellectual capabilities of a human being? And, if you have a very nationalist viewpoint, why wouldn't you want our country to have the advantage over other countries, particularly in what some people call a knowledge-based economy?" He went on: "Think about the complexity of the intellectual tasks that people need to accomplish today. Just trying to understand what Congress is doing is not a simple thing! The complexity of understanding the gamut of scientific and technical and social issues is difficult. If we had a tool that enabled more people to understand the world at a greater level of sophistication, how can we prejudice ourselves against the notion simply because we don't like athletes to do it? To me it doesn't seem like the same question. And it deserves its own debate."

The metal magnesium (Examine.com), like potassium (which didn’t help me), plays many biological roles and has an RDA for me of 400mg which is higher than I likely get (most people apparently get less, with 68% of American adults
Googling, you sometimes see correlational studies like Intake of Flavonoid-Rich Wine, Tea, and Chocolate by Elderly Men and Women Is Associated with Better Cognitive Test Performance; in this one, the correlated performance increase from eating chocolate was generally fairly modest (say, <10%), and the maximum effects were at 10g/day of what was probably milk chocolate, which generally has 10-40% chocolate liquor in it, suggesting any experiment use 1-4g. More interesting is the blind RCT experiment Consumption of cocoa flavanols results in acute improvements in mood and cognitive performance during sustained mental effort11, which found improvements at ~1g; the most dramatic improvement of the 4 tasks (on the Threes correct) saw a difference of 2 to 6 at the end of the hour of testing, while several of the other tests converged by the end or saw the controls winning (Sevens correct). Crews et al 2008 found no cognitive benefit, and an fMRI experiment found the change in brain oxygen levels it wanted but no improvement to reaction times.
The different ADHD medications like Adderall and Ritalin are classified as stimulants, and deal with these symptoms by increasing the neurotransmitters known as dopamine and norepinephrine, which are associated with pleasure, movement, and attention. They have a calming and focusing effect on people affected with ADHD, and are helpful for the inattentiveness, poor memory, impulsiveness, and mood swings experienced by those people.

Be patient.  Even though you may notice some improvements right away (sometimes within the first day), you should give your brain supplement at least several months to work.  The positive effects are cumulative, and most people do not max out their brain potential on a supplement until they have used it for at least 90 days.  That is when the really dramatic effects start kicking in!

Omega-3 fatty acids: DHA and EPA – two Cochrane Collaboration reviews on the use of supplemental omega-3 fatty acids for ADHD and learning disorders conclude that there is limited evidence of treatment benefits for either disorder.[42][43] Two other systematic reviews noted no cognition-enhancing effects in the general population or middle-aged and older adults.[44][45]

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