We wanted to talk specifically about cerebellar kids, because they are common sources of "mild" or soft neurological signs, but their impact on learning, activities of daily living (self-care, mood control, appetite), sensory-motor and sensory-sensory coordination, and social interaction can be tremendous.
It turns out the cerebellum is particularly vulnerable to prenatal or perinatal stress, and cerebellar differences are found in groups of kids diagnosed with premature birth, mild birth injury, dyslexia, ADD / ADHD, and autism spectrum disorders.
The cerebellum is sometimes referred to as the "primitive brain" because it's more along the lines of reflexive or automatic action rather than conscious thought. It used to be taught that large amounts of cerebellum could be removed (for instance because of tumor) without any significant functional deficits, but now we know that the cerebellum is involved in a lot more important cognitive functions than we were previously aware.
Looking at the complex pattern of connections that pass through the cerebellum (sensory-sensory, sensory-motor, motor-motor coordination), it may come as no surprise to you that even mild cerebellar problems can produce major practical life disruptions in a child's automatic pilot (moving, balancing, speaking, or performing other skilled activities without thinking, bodily appetites and arousal, and response to danger, pain, or environmental change). Sensory processing disorder kids are often really cerebellar kids - at least from the standpoint of a neurological exam.
It's not necessarily that a child has problems all over his or her nervous system; it may be that problems have arisen in brain location that is a great relay center for sensory inputs and motor plans.
Because the cerebellum is important for triggering escape reactions in response to threat, children with even seemingly mild cerebellar problems may have trouble with quick changes in routine, and have especially volatile emotions when young and before the frontal cognitive controls have really matured.
In the figure below, the blue areas indicate lower areas of blood flow-oxygenation in the cerebelar vermis areas of children diagnosed with pediatric bipolar disease.
The cerebellar cognitive affective syndrome -- Schmahmann and Sherman 121 (4): 561 -- Brain
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