A computer system is configured to present an individual having Alzheimer's disease or other form of dementia by stimulating the individual's brain using one or both of sensory stimulation and an electrical current. The individual's brain may be stimulated while the individual is awake, or asleep. In situations where the individual is asleep, the computer system may also determine the individual's sleep-stage. Stimulating the individual's brain induces gamma frequency activity in the individual's brain. The gamma frequency activity is captured and used to provide real-time feedback in a loop to the user regarding their brain's oscillatory activity to enhance the entrainment of the gamma frequency by the sensory stimulation and/or the electrical current.