We use both hemispheres of our brain, but theory has it that one side is usually dominant. Take this quiz to see if you favor your right or left. Your brain is a muscle. To keep it as fit as the rest of your body, you have to exercise it. Brain exercises can be active and physical or passive. Exercise your grey matter every day with Left vs Right! Our games are designed to test your Awareness, Adaptability, Reflex, Reasoning, Precision, and Patience.