Bilateral Training

Assume you never had a stroke. If you are right-hand dominant and you are trying to do something equal and opposite (like drumming) your right hand will slow so the left hand can keep up.

But it works in the opposite as well...your left hand will be able to drum faster, will have better trajectory and make fewer mistakes if you do the drumming with both hands at the same time... together. The right hand essentially trains the left hand.

After a stroke the unaffected "good" arm/hand will train the "bad" arm/hand. It's called 'bilateral transfer'. This transfer of info from one limb to the other, some scientists think, happens below the brain; right through the spinal cord, as if the two limbs are communicating directly. this may be one of the (many, many) reasons the legs usually come back sooner; bilateral transfer is used constantly during the one activity the legs are most involved in...walking. Want it to sound more scientific-y? Here's my slide for it...

Visit tia strokes to get more info about signs of a stroke.