Experimental design overview The proposed project is a prospective experimental study design. Children (age <15) suffer from attention deficit hyperactivity disorder (ADHD) that their Parents willing to participate in the study will be tested with well-established measuring techniques of Balance control before and 1 hour 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.