"In Reading in the Brain: The Science and Evolution of a Human Invention, French neuroscientist Stanislas Dehaene points out that humans did not have time to evolve reading-specific brain circuitry; instead, our brain “recycles” existing networks for the task. "
This concept helps explain why it is that clapping your hands and stomping your feet improves reading scores.
One of the most difficult concepts in IM to grasp is the concept that doing a physically challenging activity helps MENTAL processing necessary for reading and math. Research proves this is the case, but how? Dehaene stated it very clearly in the statement above - we use these efficient neuronetworks that we build in our motor and sensory processing areas for reading. "We 'recycle' existing networks for the task."
Later he wrote: "The goal of reading instruction becomes very clear. It must aim to lay down an efficient neuronal hierarchy...."
Many of the children I see do not have efficient neuronal networks. Sometimes it's just one or two neuro-networks, such as crossing midline or a weak right hemisphere of the brain. Other times it's a system wide issue with timing issues through out the entire brain and various sensory networks besides. The more networks needing fine tuned or sometimes even built from scratch, the more the child has to gain from IM...... and the more IM the child should do. It's all about building efficient neuronal networks.