In some individuals, this causes significant traction and stress on the spinal cord and can lead to a worsening of associated paralysis, scoliosis, back pain, and worsening bowel and/or bladder function. Neurological problems
Many individuals with spina bifida have an associated abnormality of the cerebellum, called the Arnold Chiari II malformation. In affected individuals, the back portion of the brain is displaced from the back of the skull down into the upper neck. In about 90% of the people with myelomeningocele, hydrocephalus also occurs because the displaced cerebellum interferes with the normal flow of cerebrospinal fluid, causing an excess of the fluid to accumulate. In fact, the cerebellum also tends to be smaller in individuals with spina bifida, especially for those with higher lesion levels.The corpus callosum is abnormally developed in 70–90% of individuals with spina bifida myelomeningocele; this affects the communication processes between the left and right brain hemispheres. Further, white matter tracts connecting posterior brain regions with anterior regions appear less organized. White matter tracts between frontal regions have also been found to be impaired.Cortex abnormalities may also be present. For example, frontal regions of the brain tend to be thicker than expected, while posterior and parietal regions are thinner. Thinner sections of the brain are also associated with increased cortical folding. Neurons within the cortex may also be displaced. Executive function
Several studies have demonstrated difficulties with executive functions in youth with spina bifida, with greater deficits observed in youth with shunted hydrocephalus.
Unlike typically developing children, youths with spina bifida do not tend to improve in their executive functioning as they grow older. Specific areas of difficulty in some individuals include planning, organizing, initiating, and working memory. Problem-solving, abstraction, and visual planning may also be impaired. Further, children with spina bifida may have poor cognitive flexibility. Although executive functions are often attributed to the frontal lobes of the brain, individuals with spina bifida have intact frontal lobes; therefore, other areas of the brain may be implicated.Individuals with spina bifida, especially those with shunted hydrocephalus, often have attention problems. Children with spina bifida and shunted hydrocephalus have higher rates of ADHD than children without those conditions (31% vs. 17%). Deficits have been observed for selective attention and focused attention, although poor motor speed may contribute to poor scores on tests of attention. Attention deficits may be evident at a very early age, as infants with spina bifida lag behind their peers in orienting to faces. Academic skills
Individuals with spina bifida may struggle academically, especially in the subjects of mathematics and reading. In one study, 60% of children with spina bifida were diagnosed with a learning disability. In addition to brain abnormalities directly related to various academic skills, achievement is likely affected by impaired attentional control and executive functioning. Children with spina bifida may perform well in elementary school, but begin to struggle as academic demands increase.Children with spina bifida are more likely than their peers without spina bifida to be dyscalculic.