“You know how they say that we can only access 20% of our brain?” says the man who offers stressed-out writer Eddie Morra a fateful pill in the 2011 film Limitless. “Well, what this does, it lets you access all of it.” Morra is instantly transformed into a superhuman by the fictitious drug NZT-48. Granted access to all cognitive areas, he learns to play the piano in three days, finishes writing his book in four, and swiftly makes himself a millionaire.
Methylphenidate – a benzylpiperidine that had cognitive effects (e.g., working memory, episodic memory, and inhibitory control, aspects of attention, and planning latency) in healthy people. It also may improve task saliency and performance on tedious tasks. At above optimal doses, methylphenidate had off–target effects that decreased learning.
The main concern with pharmaceutical drugs is adverse effects, which also apply to nootropics with undefined effects. Long-term safety evidence is typically unavailable for nootropics. Racetams — piracetam and other compounds that are structurally related to piracetam — have few serious adverse effects and low toxicity, but there is little evidence that they enhance cognition in people having no cognitive impairments.