I've taken several nootropics specifically targeted at improving memory for medical school studying (Ginkgo biloba, Bacopa monneira, Huperzine A, Vinpocetine, Fish Oil, Rhodiola rosea, L-Theanine, Choline-bitartrate, Acetyl-L-carnatine, and a slew of multivitamins, etc.), and while these did have a noticeable effect on my memory and motivation to study, they all led to a major crash at 1-2 half lives-- depending on their therapeutic window (the blood concentration that both has an effect and is not toxic). Each resulted in a significant reduction in declarative recall (but not procedural memory) for me in this refractory window (the crash). Ginkgo and Rhodiola were the most "stimulant" oriented for me of those, and worked well in both motivational and mnemestic regards, but it they had the hardest "nap time!" crash effect in the afternoon. I attribute this to their pharmacodynmic behavior as a mild MAO inhibitors (similar to old generation atypical antidepressants that prevent the degradation of epinephrine, norepinephrine, and dopamine by monoamine oxidase). Rhodiola is a pretty potent MAOI, which leads to monoamine tolerance (not to mention some excess body odor from apocrine sweat glands, and a potentially dangerous hypertensive reaction with tyramines found in Cheese and Wine). I took Ginko the most regularly as it is not specifically an MAOI and has other effects increasing cranial blood flow and possibly enhancing acetylcholine transmission in the hippocampus. This was every day for a year, 2 or 3 times a day at 60-120mg. I found the best result with Extended Release 120mg. Bacopa was also great for about 6 weeks but I then began to notice its least desirable side effect. It has been shown to lead to testicular atrophy and (supposedly) reversible infertility in a few studies, so while it was often more stable for me than Ginko, I chose to avoid it. I did experience a loss of libido from this, but have since returned to normal testicular mass and sexual desire. Apparently it inhibits ledig cells.
I've recently started Piracetam. I experience an enhanced cerebral recall, which makes sense given its proposed pharmacodynamic behavior at the AMPA and NMDA receptors. I do not experience hippocampal recall enhancement... vinpocetine and huperzine A were excellent for this, but the short duration and inevitable acetylcholine tolerance are unacceptable for me. Perhaps useful only on exam days. Occasional continued Ginko use helps boost my hippocampus when needed, at the risk of excess stimulation/jitters.
For me the nature of the memory recall with Piracetam is different than many "memory enhancing" nootropics in that recall is unlikely be/feel more "instantaneous" or "certain," but will instead be more voluminous and thorough once a particular cerebral storage area for the given memory is activated by hippocampal pathways. There's also speculation (and at least personal confirmation here) that Piracetam improves memory consolidation through modulation of the previously described receptors (AMPA/NMDA). I find that I retain what I've studied much more reliably with Piracetam than with Ginkgo, but that the combo of the two helps more with regurgitating this info... especially verbally. Combining Piracetam with Ginkgo, Vinpocetine, Huperzine A or another Acetylcholine esterase inhibitor or Agonist will likely help with hippocampal activation to achieve this effect (think of it like opening the memory gateway to a warehouse vs just increasing the size and efficiency inside the memory warehouse itself with Piracetam alone-- which acts on cerebral neurons and may only slightly aid hippocampal ones.).
Choline-bitartrate supplements may work to aid this process, but the evidence for Choline actually crossing the blood brain barrier and having an effect is limited (unless one is already significantly deficient in acetylcholine and thus synthesis, conversion to acytelcholine, and import into the brain may be enhanced. This would be caused by excess Huperzine, Vinpocetine, and possibly Ginkgo use -- among other Alzheimer's supplements/prescriptions which are aimed at stimulating the activity of the nucleus basalis of meynert in the basal forebrain).
L-Glutamine may potentially work by the same concept as Choline-bitartrate, but on cerebral glutamate neurons instead of the more hippocampal acetylcholine neurons. I have ordered some of this from Amazon, but have yet to try it. I plan to add it to my "Intense Day" stack.
For bedtime I enjoy a bit of Cannabis to enhance neuroplasticity and relaxation with some regularity. I also use 5-HTP, Valerian root, and Acetyl-L-carnatine + Propionyl-L-carnatine if I'm too hyped up or feeling depleted from going too hard.
Anyways, this is my current stack:
Daily:
-Spark Energy Drink from Advocare (1-3 scoops per day) -- http://www.advocare....tive/A2094.aspx
(contains a lot of caffeine, choline, and other vitamins that are very common to this forum)
-Fish Oil (1100mg, extended release)
(make sure it's chetelated for mercury, and cod liver oil is best, but spendy.)
-Piracetam 800mg per 4.5 hours, 3 times per day.
Intense Days:
-All the above.
-L-Glutamine 1-5g added to Spark (will experiment)
-Ginkgo Extended Release -- 120mg, per 6 hours, twice a day.
-L-Theanine, 100mg as needed if feeling impending Ginkgo crash or too jittery.
Exam Days:
-All the Above
... then immediately before test...
-Vinpocetine 10 mg
-Huperzine A 100 mcg
Nighttime:
- 0.2g Cannabis sativa, vaporized via Volcano, or in olive oil tincture.
- 100 mg 5-HTP and Valarian Root 20mg if feeling burnt out and desiring a nice long sleep.
- Acetyl-L-carnatine + Propionyl-L-carnatine (Acetyl-L-carnatine may actually result in some restless legs, hyper-motor activity in some people.)
Lastly, a word of caution: After reading these forums, I was shocked by the quantity many people are dosing with these drugs. 12 grams of Piracetam, or a gram of Ginkgo at once is crazy, and you risk blowing an aneurysm or bleeding out from the anticoagulant and hypertensive effects of these drugs. Also, a huge dose all at once is foolish. The half life on these is between 5-7 hours depending on your kidney function, better equals faster. It's much better to take lower doses more frequently. You should always be seeking the MINIMAL therapeutic dosage with nootropics, and any supplement for that matter. Many supplements have a very potent effect that is not necessarily dosage dependent, and varies from person to person. Many supplements, just like prescription drugs, have serious adverse effects that are often NOT noticeable at the time, or even for years. The greatest concern is generally cancer (bladder is a common example several of the mineral vitamins, for example), kidney failure, liver cirrhosis/failure, and (with nootropics) neurotransmitter receptor desensitization. These are a very real risk. Many of you may bock at the "low" dosages I've indicated in my above stack, and that's fine with me. I'm currently in the most intense portion of my medical training, I use my mind more than I have ever before in my life. Through the next 8 months, I will be using it more intensely than I probably ever will again. I notice a truly efficacious difference at these dosages and have steadily moved up in class ranking since starting my quest into nootropics. I plan to cut out much of it once I've finished by board exams. If none of that convinces you, consider this. The dosages I listed are on the low-mid range of the spectrum for peer reviewed research papers that have held up to scrutiny in regard to effectiveness and safety in DEMENTIA patients. The research for young, health people is very limited, as reputable medical researchers are generally looking to help the sick and not enhance the healthy. The studies indicate safety for most of these drugs at about 2 years out, at most-- many of their patients (with dementia) often opt or die of complications related to their their illness at this point. What this means is that for the short term, all this stuff is probably safe if responsibly administered at minimum therapeutic dosages in young people, but there is NO evidence out there supporting long term safety 20-50 years out when one begins to consider things like long term brain damage and dementia from the nootropics themselves or cancerous malignancy.