Nootropics ( noh-ə-TROHP-iks or noh-ə-TROP-iks; but not new-TROHP-iks or new-TROP-iks, which are common mispronunciations), colloquially brain supplements, smart drugs and cognitive enhancers, are natural, semisynthetic or synthetic compounds which purportedly improve cognitive functions, such as executive functions, attention or memory.