Static and Dynamic Balance in Children With Dyslexia

Dyslexia is described as a learning disability with a neurological origin. It is a widespread disease, characterized by difficulties in recognition of words, spelling, and decoding. It is an unexpected and permanent failure in gaining reading skills in the individual who have sufficient intelligence, socio-cultural opportunities, and education, according to the World Health Organization. The diagnosis can be made by a child and adolescent psychiatrist clinically or with the Diagnostics and Statistical Manual of mental disorders (DSM-5). The prevalence of dyslexia varies between 2-10%, and it is seen 3-4 times more in men than in women.

Postural balance is the ability to control the center of gravity (CoG) on the support base. This control starts to appear at the beginning of the 15th months of life and reaches its maximum capacity at around 12 years with the maturation of visual, vestibular, and somatosensory systems. Static balance defines the postural control state in the maintaining position, while dynamic balance represents it during movement. Static and dynamic balance has been widely investigated and found to be impaired in different pediatric disorders such as cystic fibrosis, cerebral palsy, and spina bifida. There is also apparent evidence of deteriorated balance in children with dyslexia. Frankle and Levinson suggested that there is a cerebellar-vestibular disorder in people with dyslexia for the first time in 1973. They found that 97% of 115 children with dyslexia abnormal neurological findings such as positive Romberg test, walking difficulty, speech disorder, or hypotonia. After then, Rae et al. reported that the right frontal lobe of the cerebellum was smaller, and there were distinct biochemical changes on the temporoparietal lobe in dyslexic individuals compared to healthy controls. Moe-Nilssen et al. showed that dyslexic children have impairment in both balance and gait ability. Barela et al. claimed that writing and learning disorders in dyslexia were associated with cerebellum. Patel et al. found that postural instability was related to the severity of dyslexia. Quercia et al. gave postural exercise treatment to the dyslexics, then examined their postural stability after a vibrational stimulation. The length and speed of CoG were shown to be significantly higher in untreated dyslexic patients compared to the treated dyslexics and the non-dyslexic group.

Although quite a number of studies investigated balance impairment in individuals with dyslexia, only one study was interested in the effects of a postural training program and found significant improvements. That study addressed such improvements to brain plasticity, however, did not investigate the reading performance simultaneously. The aim of this study was to demonstrate the changes in static and dynamic balance, reading performance, and quality of life after a six week after a scheduled exercise program in children with dyslexia.