Hericium erinaceus (Examine.com) was recommended strongly by several on the ImmInst.org forums for its long-term benefits to learning, apparently linked to Nerve growth factor. Highly speculative stuff, and it’s unclear whether the mushroom powder I bought was the right form to take (ImmInst.org discussions seem to universally assume one is taking an alcohol or hotwater extract). It tasted nice, though, and I mixed it into my sleeping pills (which contain melatonin & tryptophan). I’ll probably never know whether the $30 for 0.5lb was well-spent or not.
I don’t believe there’s any need to control for training with repeated within-subject sampling, since there will be as many samples on both control and active days drawn from the later trained period as with the initial untrained period. But yes, my D5B scores seem to have plateaued pretty much and only very slowly increase; you can look at the stats file yourself.
Choosing to take smart drugs is not an effective or long term solution. Smart drugs may help you study faster or keep you awake longer, but they are not your best option. Most of the ADHD medications are based on an amphetamine structure and they are not healthy for your heart or your liver. Also, by taking smart drugs, you are putting yourself at considerable risk for addiction to these substances.
Nootropic (new-tro-pik) is the term for supplements, also known as smart drugs, that improve brain function. They can be food substances like phenethylamine and L-Theanine, found in chocolate and green tea, respectively. Nootropics also include extracted and purified components of medicinal plants, as well as substances synthesized from chemical precursors, such as piracetam, the world's first official nootropic (piracetam was created in 1964 in Belgium by a team of scientists whose leader, Dr. Corneliu E. Giurgea, coined the term). Since then piracetam has been widely used as a cognitive enhancer and to treat neurological diseases like Alzheimer's.
Oxiracetam is one of the 3 most popular -racetams; less popular than piracetam but seems to be more popular than aniracetam. Prices have come down substantially since the early 2000s, and stand at around 1.2g/$ or roughly 50 cents a dose, which was low enough to experiment with; key question, does it stack with piracetam or is it redundant for me? (Oxiracetam can’t compete on price with my piracetam pile stockpile: the latter is now a sunk cost and hence free.)
With a lack of reviews and a formulation containing some questionable ingredients that we could not find to benefit consumers, together with the possibility of the product being sub-standard, we placed this product in our # 4 ranking. Its redeeming features however, include the fact that they use all-natural ingredients plus, the price is cheap, if you are into taking a risk about the quality of the product.

Eugeroics (armodafinil and modafinil) – are classified as "wakefulness promoting" agents; modafinil increased alertness, particularly in sleep deprived individuals, and was noted to facilitate reasoning and problem solving in non-ADHD youth.[23] In a systematic review of small, preliminary studies where the effects of modafinil were examined, when simple psychometric assessments were considered, modafinil intake appeared to enhance executive function.[27] Modafinil does not produce improvements in mood or motivation in sleep deprived or non-sleep deprived individuals.[28]