Experimental design overview The proposed project is a prospective experimental study design. independent old adults(age 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.

Inclusion Criteria:

• Age 65 years old and older
• independent elderly adults
• do not suffer from balance prblems
• minimental score 24 and above

Exclusion Criteria:

• old adults who suffer from neurological disease or stroke
• old adults who suffer from psychiatric state
• old adults who suffer from orthopedic condition (1/2 a year after a fracture in the lower limb)
• old adults who suffer from heart conditions
• old adults who suffer from blindness