 Experimental design overview The proposed project is a prospective experimental study design. independent old adultsage 65 years old and older who do not suffer from balance problems willing to participate in the study will be tested with well-established measuring techniques of Balance control before and 2 hours after taking of Methylphenidate Ritalin in the movement and Rehabilitation Laboratory at BGU. An automated algorithm will be used to extract standardized stabilogram-diffusion parameters from each of the COP data sets collected during quiet standing. These parameters include diffusion coefficients, critical displacement, critical time and scaling exponents for both lateral and anterior-posterior sway directions Collins De Luca, 1993. For each of the conditions before and 1 hour after the use of Ritalin in three task conditions single task; dual task concentrating and identifying specific music; and just Listening to a relaxing music. Participants will be required to stand on the platform 10 times for 30 s. For each trial, they will be instructed to sway as little as possible. 