‘Now, a new study in the journal Science Advances from researchers at the University of Melbourne and the University of Cambridge — Elizabeth Bowman, David Coghill, Carsten Murawski, and Peter Bossaerts — finds that far from making users smarter, smart drugs seem to actually undermine cognitive performance.

The authors tested the effects of three drugs — methylphenidate (more commonly known through one of its brand names, Ritalin), modafinil, and dextroamphetamine* (brand name Dexedrine, among others) — on a cognitive task designed to more closely mimic the complexities of real-world problems than past stimulant studies.

Far from simply concluding that smart drugs offer little benefit, the researchers found that the drugs actually seemed to leave users worse off. While study subjects worked harder while on the drugs compared to placebo, the “quality of effort,” or productivity, actually declined. The upshot is that smart drugs led users to spend more effort working while being less productive — not exactly a picture of cognitive enhancement….’ (Vox)

* one of the two active components of popular ADHD stimulant Adderall -ed.