Among the most promising cognition treatments are vortioxetine, which has shown replicated effects on psychomotor speed in symptomatic MDD28, modafinil that improved some aspects of cognition in a study of remitted MDD29, transcranial direct current stimulation that improved working memory in symptomatic MDD30,31, lurasidone that improved a global measure of cognition in remitted BD32 and erythropoietin (EPO) that improved several cognitive domains in symptomatic MDD and remitted BD33,34. This evidence concerns the gene EPO and major depressive disorder.