Ambidexterity is when a person can use both sides of their body equally. Mostly using both hands to do physical activities with the same efficiency. There are four types of handedness, right-handed, left-handed, mixed-handed, and ambidextrous. Usually referring to being able to use both hands dominantly. Most people who are right handed dominant have a more dominant left hemisphere of the brain. However ambidextrous people have no dominant hemisphere in their brain. Meaning ambidextrous people can at times use both sides of their brain.

To test this theory you can do a couple of experiments on your own using body motions. One example is lifting your right leg and making a clockwise rotation with your right foot. While continuously doing this motion, take your right hand and draw the number six in the air with your right hand.
Test two is take your right arm and in a fast motion act as if your punching a speed bag and then take your left arm and do the same motion but going in the opposite direction at the same speed without stopping.
Test two is take your right arm and in a fast motion act as if your punching a speed bag and then take your left arm and do the same motion but going in the opposite direction at the same speed without stopping.