The information in the brain is processed
contralaterally.
Each hemisphere of the brain controls opposite side of
body parts.
This means, left side of the brain process
information for right side of the body AND
right side of the brain process
information for left side of the body.
Stroke is diminised or disrupted supply of blood to a region of
the brain.
Hence, if a stroke occurs on one side of the brain, movement on
the other side of body are affected. Example : If there is diminished blood supply to
right hemisphere, functions such as muscle movement, sensation of
left side of the body are affected.