Methylphenidate (Concerta, Ritalin) for executive function
Methylphenidate is one of the stimulant medications used mainly to treat attention deficit hyperactivity disorder (ADHD) in children. The brand-name versions of the drug include Ritalin and Concerta. All the stimulant medications used to treat ADHD work by augmenting the activity of dopamine in the brain. Dopamine influences many cognitive processes, including executive function.
But when methylphenidate has been tested as a treatment for older people with cognitive deficits, the results have been a mixed bag: some promising, some not so much, which leaves room for more research but hardly a clear path into everyday clinical practice.
Furthermore, the drug's effect on memory, depression, and various other aspects of mental life has been measured, but very few studies have tackled executive function head on. In 2003, British researchers reported that methylphenidate didn't seem to have much of an effect on an older brain. The "cognitive effects of methylphenidate are grossly attenuated" in the elderly, they said in a summary of their results (the abstract).