Movement, Performance, and Cognition
“Movement cannot be separated from perception and cognition; these processes are continually and dynamically interacting. The acts of perceiving and planning are always in reference to eventual movement, and the movement is part of what is being remembered. Over a lifetime, I believe, these interactions with the world construct our cognition and maintain it.” [emphasis mine] (Thelen, 2004). The energy spent constructing a world of objects, sights, sounds, colors, shapes, dimensions, and directions is enormous. Without the incredible and finely tuned machine called our body, our brain would be at a loss to describe the world. Our ability to see, touch, feel, hear, move, and control ourselves in relationship to the environment is the slate that academic learning is etched on (Oden, 2006).
For a child to communicate his desires, his thoughts, or his knowledge, motor skills are necessary, for example, in the form of writing, speaking, or keyboarding. These motor skills which accomplish a task are born of multiple system interactions, according to the Dynamic Systems Theory. This theory, which is the current guide for our understanding of development and movement, states that movement emerges not through a single cause and effect of sensory stimulus-motor response, but through the interaction of various systems: brain, spinal, and peripheral structures along with biomechanical, environmental and social structures available at the moment, including the particular task at hand (Bundy & Murray, 2002; VanSant, 2003). Movement is the end result of all the possibilities and constraints(limitations or restrictions) offered by all the contributing systems. Possibilities and constraints can even include growth issues such as the arm length of a six year old. The Dynamic Systems Theory views the brain’s function in the movement as a whole; the actual output of the brain to the external world is manifested as movement (Bertoti, 2004).
Reflexes: Hierarchal Theory vs. Dynamic Systems Theory
Maturation and developmental change was at one time thought to only correlate in a linear manner with the maturation and development of the CNS (central nervous system). This narrow view has now been expanded. It does not operate on the hierarchal timeline once considered to be the concrete framework for all the developmental progress. It is currently understood that development is never static. Development is a process of assembling patterns of behavior to meet the demands of a task within the biological possibilities of the child at that precise moment (Thelen, 2004).
The Dynamic Systems Theory suggests that new motor skills emerge through the process of the self-organization of multiple systems, rather than by a hard-wired hierarchal framework, such as the historic perspective on reflexes (Kamm, Thelen, & Jensen, 1990). Because of this, one of the principles of the Dynamic Systems Theory is complexity. Every behavior is the condensation of heterogeneous components. There is rarely a single clear-cut cause for a behavior. No one factor, whether internal or external, or one system, whether CNS or musculoskeletal, has a greater influence than another. Maturation is no longer considered a step-by-step process, as in the former reflex hierarchy, but instead is an increase in complexity in multiple systems allowing for more sophisticated functioning. Even though human balance and coordination are too complex for innate reflex patterns to be a satisfactory explanation, these reflex patterns must still somehow be considered as part of the movement system and therefore an influence.
The Dynamic Systems understanding does not deny reflexes (Heriza, 1991; Shumway-Cook & Woollacott, 2001). Reflexes do exist, as consistent patterns that occur more frequently than by chance (Clotpon, 2000). But the former term ‘primitive’ reflex is considered archaic and misleading in that it suggests an incompetent infant brain (Pimental, 1996). Other terms describing these early motor movements, including the term ‘reflex’ are being explored, changed, and even discarded in developmental literature. “Early motor behavior itself has not changed but how we conceptualize what that motor behavior represents has changed” (Montgomery & Effgen, 2005). Sherrington’s 1906 work describing reflex theory focused on decerebrate animals to describe the patterns of reflexive movement. Yet we should look at these movements not as lock-in patterns of a decerebrate cat, but as general motor patterns, or as deep attractors as per the Dynamic Systems Theory. This leads to the second principle of dynamic systems, namely dynamic stability. There are within us some consistencies—stable patterns that we use regularly which will be replaced as we develop other more useful and stable patterns. Thelen and her colleagues, who defined the Dynamic Systems Theory approach, stated, “Reconsider the so-called primitive reflexes, indeed not as hard-wiring, but as the infant’s propensity under certain circumstances to exhibit a particular motor response” (Kamm, Thelen, & Jensen, 1990). As such, it is valuable to discuss and list the reflexes seen as part of the dynamic unfolding of continually developing postural control (Bertoti, 2004).
The development and organization of postural control is built on prior experiences, as is the ability to plan any successful action (VanSant, 2005). Because the many systems self-organize with experience, preferred patterns of motor behavior will emerge. They will reflect the most efficient pattern available to the child at a certain time, in a defined environment, dealing with a particular task. Whether that task is jumping, writing, or remaining still in a classroom chair, all sensory and motor system abilities form the foundation for the performance of that task. Therefore, the Ready Bodies Motor Lab addresses the needs of allstudents in task-oriented circuit training, supported by consistent, foundational exercises, offering developmental support for each system.
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