There are some oversights when it comes to traditional rehabilitation therapies when compared to advances in neuroscience research. The idea of focusing on muscles instead of the brain, doing mindless repetitions with no attention paid to movement to create “muscle memory” will only provide limited outcomes.
The whole idea of thinking in terms of muscle memory instead of the brain is backwards. There is no question that to be able to move, we need our muscles, and that stronger muscles provide us with the possibility for stronger, more powerful movement and stamina.
However, muscles do not know what to do on their own. It is the brain that “tells” the muscles what to do—when to contract and when to let go—through the signals it sends to the muscles through our nervous system. And in order for the brain to know what signals to send to our muscles, it has to first “know” that the muscles are there to be used and learn how to coordinate the different muscle groups successfully. The brain needs a rich variety of experiences from which it creates the necessary connections and patterns of our movements, also known as “mapping” in the brain. When a child has cerebral palsy and not muscular dystrophy – they have nothing wrong with their muscles, they have a brain injury and need to learn that the part of the body that lost functionality from the brain injury exists before they start learning to move those parts. That happens through self exploration and movement, and we can amplify their learning using touch and a variety of gentle movements.
Brain research, cited below, has shown that movement done automatically does not create new connections in the brain, but rather it grooves in more deeply existing brain patterns (those stubborn limitations, making the limitations and poorly organized movement more pronounced instead of introducing proper function). However, the moment we bring attention to what we feel as we do any movement, there is an immediate, dramatic increase in the number of new connections associated with the areas of body that we are moving.
A physiotherapist once told me ”the brain needs repetitions to form muscle memory.” Based on the above research that’s fairly inaccurate. There’s no doubt that when a child with Cerebral palsy is performing new functions and paying attention to how they are moving this is improving their brain mapping, so movement even rudimentary movement can be helpful. Movement with attention is effective as learning is actually occurring, but some of what they are doing in therapy is introducing limitations by using force or doing the movement “for the child” instead of allowing them to discover “how to do” it. Such as putting them in sitting to learn how to sit, when there’s a foundation of learning needed; mapping the relationships between the pelvis, head and spine to have sitting naturally occur without effort. Mindless repetitions and the focus on muscles before brain is a limited approach and will produce limited outcomes. While new experiences and variations within the child’s present ability while they are paying attention and aware of the movement is helpful to build a better brain, allowing for learning to better organize their movements, for example, they learn where to put their head to make coming up to sitting easy. Spasticity occurs when the muscles are overworking to keep a child upright in the gravitational field. When we help them to feel how to shift their weight to transfer through their bones, balance improves and spasticity decreases.
Children put into sitting or standing before they know how to get there on their own creates a chain of disorganization as they brace themselves against falling, which is an intelligent response, but it creates more effort, which makes it even harder to move, and isn’t how you learned to come up to sitting and standing if left to your own self learning and discovery. When a child learns to “get into” a position the “getting out” of the position is automatic too, as ideal movement is reversible. I’ve worked with a number of children over the years who had no idea how to walk, as they were placed in standers or walked by parents behind them. They carried their head so far behind their spine that shifting their momentum forward was an impossible feat. They had not learned a way to bring their hands down to the floor to come down to rest and get out of the standing position. They learned to lock their knees to support their weight, making taking steps forward an impossible task. I watched them in physiotherapy walking while the therapist moved their lower legs to walk them. This creates a myriad of disorganization in movement, as our legs don’t walk us; catching the weight with the legs initiated by swiveling the pelvis does.
Think of movement with attention as bringing about a virtual explosion of activity in the brain: Scans showed high levels of activity in the prefrontal cortex during new learning but not once the performance became routine.
It’s so important when learning a new skill to go slow and do less repetitions until the ideal movement is formed. Reducing force and doing it many different ways provides the system with rich information to discover how to make the movement easy. At that time repetitions are helpful to form the ideal movement pattern in the brain. I think this is what’s commonly referred to as muscle memory, it’s our auto-pilot. The more our auto-pilot is tuned to ideal movement that allows for easy transitions and distribution of effort through our skeleton, the easier it becomes to move. To use repetition with a less than ideal movement pattern to simply do “the thing” (walk or crawl or stand) as part of a rehabilitation strategy, is only going to introduce and groove in a limitation, making effortless movement harder to obtain. Our brain is constantly learning from every experience, whether it’s making movement easier or making movement harder.
Research shows that movement done automatically creates little or no new connections in the brain:
“[T]he variable determining whether or not the brain changes is . . . the attentional state of the animal.” Schwartz J, Begley S. 2002, rpnt 2003.
The Mind and the Brain: Neuroplasticity and the Power of Mental Force. New York: HarperCollins. Recanzone G. H, Merzenich MM, Jenkins WM, et al. 1992.
Topographic reorganization of the hand representation in cortical area 3b of owl monkeys trained in a frequency discrimination task. Journal of Neurophysiology 67: 1031-56. Nudo RJ, Milliken GW, Jenkins WM, Merzenich MM. 1996
Use-dependent alterations of movement representations in primary motor cortex of adult squirrel monkeys. Journal of Neuroscience 16: 785- 807. See Doidge N. 2007. The Brain That Changes Itself. New York: Viking/ Penguin.
Jueptner M, Stephan K, Frith CD, et al. 1997. Anatomy of motor learning. I. Frontal Ccrtex and attention to Action. Journal of Neurophysiology 77(3): 1313- 24. Johansen- Berg H, Matthews PM. 2002.
Attention to movement modulates activity in sensori- motor areas, including primary motor cortex. Experimental Brain Research 142(1): 13- 24. “Experience coupled with attention leads to physical changes in the structure and functioning of the nervous system”: Merzenich MM, deCharms RC. 1996.
“Neural representations, experience and change.” In Llinàs R, Churchland PS, eds. The Mind-Brain Continuum. Cambridge, MA: MIT Press.