How do you separate the effects of the drug from simply learning how to take the test? Theoretically, you can't learn how to take an IQ test and no matter how much you "study", your score won't increase, at least not by much, but that's not the case with most standardized tests. A proper study regimen and no drugs can produce significant improvements on tests like the SAT, GRE and MCAT. That's why study courses exist which guarantee certain levels of improvement. So maybe your scores increased because of practice. I also think the benefits of nootropics are greatly exaggerated, mostly by people who want a simple solution for the difficult problem of cognitive improvement. I don't think that solution exists. You can't just pop up a pill and raise your IQ by 20 points. But there are activities that can improve your memory, reasoning skills, reading comprehension, etc. Mostly they involve memorizing, solving logic problems, and reading.