Motor Assessment

Neuroanatomy

The motor system is contained within the front part of the brain. This motor strip controls the execution and maintenance of simple motor functions. It is a crossed system so that the right hemisphere motor strip located on the right side of the brain controls the left side of the body, and vice versa. The premotor cortex lies in front of the motor strip and directs the primary motor cortex.

In addition to the frontal lobes, the parietal lobe is also involved with the motor system. The parietal lobe lies in the superior portion of the back of the brain. This section allows for not only the perception of touch and temperature, but also an awareness of the position and movement of body parts (kinesthetic sense). Similar to the motor system, the sensory system is also a crossed system. It is particularly important for motor skills in that the primary parietal region allows for a rapid cross-communication with the motor system, which is necessary for the execution of motor behavior (Teeter & Semrud-Clikeman, 1997).

In addition to the sensory and motor cortices, the ability to integrate motor skills and visual information [Page 336]is an important part of motor control. The juncture of the occipital, parietal, and temporal lobes has been implicated in visual–motor integration. This juncture lies in the posterior portion of the brain where the three lobes connect. For some children, fine motor skills may be intact but they experience difficulty integrating what they see with what their hands/fingers are reproducing. These children may have difficulties in visual–motor integration, but have adequate fine motor skills. Similarly, a child with fine motor skill deficits may experience difficulties with visual–motor tasks that are not caused by perceptual deficits. Fine motor skills are those that allow a person to complete a task with his or her hand, while perceptual skills are those that allow understanding of what the person sees.

The school psychologist needs to tease apart the difficulties a child may have through the use of fine motor tests as well as perceptual tasks that are not heavily involved motorically. For example, child with cerebral palsy may perform poorly on a visual–motor task because of obvious motor problems and should be tested for perceptual accuracy on tasks that do not have a motor component. Similarly children with tremors, arthritis, or motor slowing may do poorly on measures of visual–motor integration for these reasons and not because of perceptual difficulties. In addition, children with motor difficulties may do poorly because of their positioning. It is very helpful to have a physical therapist or occupational therapist assist the psychologist in positioning the child for optimum performance.

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