This invention relates to the treatment of varying degrees of cognitive impairment associated with, for example, aging, Alzheimer’s disease, schizophrenia with low dose administration of a PDE4 inhibitor, specifically roflumilast.本發明係關於以低劑量投與PDE4抑制劑(明確言之羅氟司特(roflumilast))治療與(例如)衰老、阿茲海默氏病(Alzheimers disease)、精神分裂症相關聯之各種程度的認知損傷。