Abstract: Compositions for enhancing memory of a subject comprising a combination of a positive modulator of an AMPA receptor and a positive modulator of an NMDA receptor are provided, wherein each modulator of the combination is present at a subtherapeutic dose for effecting memory enhancement. Methods for using such compositions in the treatment of cognitive impairment associated with aging, age-related diseases, and CNS disorders, for example, are provided. New fusion molecules are also provided that combine the positive modulator functionalities into one molecule.