Real smart drugs = nootropics = piracetam and piracetam-like molecules. Stimulants generally decrease performance, increase false positives, and lead to worse performance as this study showed (especially in a first time user).
Most nootropics take about 14 days to hit their stride and the effect isn't discernible immediately (though can be detected in an EEG)...
See study: "Increase in the power of human memory in normal man through the use of drugs"
"Nootropyl (Piracetam) a drug reported to facilitate learning in animals was tested for its effect on man by administering it to normal volunteers. The subjects were given 3x4 capsules at 400 mg per day, in a double blind study. Each subject learned series of words presented as stimuli upon a memory drum. No effects were observed after 7 days but after 14 days verbal learning had significantly increased."
https://pubmed.ncbi.nlm.nih.gov/826948/
Study: "Single-dose piracetam effects on global complexity measures of human spontaneous multichannel EEG"
"The results indicate that a single dose of piracetam dose-dependently affects the spontaneous EEG in normal volunteers, showing effects at the lowest treatment level. The decreased EEG complexity is interpreted as increased cooperativity of brain functional processes."
https://pubmed.ncbi.nlm.nih.gov/10555876/
Study: "Single doses of piracetam affect 42-channel event-related potential microstate maps in a cognitive paradigm"
"U-shaped dose-dependent effects were found; they were strongest after 4.8 g piracetam. Since these particular ERP segments are recognized to be strongly correlated to cognitive functions, the present findings suggest that single medium doses of piracetam selectively activate differently located or oriented neurons during cognitive steps of information processing."