According to the third edition of America's Children and Environment (2011), the prevalence of neurodevelopmental disorders has been increasing over the past four decades. A neurodevelopmental disorder is defined as a disorder that affects the nervous system. These conditions include attention deficit hyperactivity disorder (ADHD), autism, cerebral palsy, Down syndrome, dyslexia, dyscalculia, and fragile X syndrome. Such disorders take more of a physical toll on the diagnosed individual. Neurodevelopmental disorders take a heavy financial, emotional, and mental toll on affected family members throughout the diagnosed individual's development. Special educational, medical, and support services are needed for people diagnosed with a neurodevelopmental disorder. The causes of these disorders are generally accepted as multifactorial: they can be caused by anything related to genetic factors and environmental agents. However, the true causes of most of the listed disabilities remain unknown and highly debated. These conditions, their causes and ramifications will be discussed in depth in this article. The most common of childhood brain disorders is the first neurodevelopmental disorder to be discussed, attention deficit hyperactivity disorder. Attention deficit hyperactivity disorder is commonly abbreviated and referred to as ADHD. Severe and persistent symptoms of inattention, hyperactivity, and impulsivity are the best indicators of attention deficit hyperactivity disorder. The maturation pattern in the affected brain appears normal, but hindered by an average of three years. Genetics and prenatal factors appear to be major contributors to the development of ADHD in a child. The research implies that attention is lacking... in the middle of the paper..., for unexplained reasons. Another medical condition that people with fragile X syndrome are more prone to get are ear infections. Ear infections are common in boys with the syndrome. If regular, this can lead to hearing loss. Twenty to 25 percent of people with fragile X syndrome also have an autism spectrum disorder. Autism typically affects social interaction and communication skills in individuals with fragile X syndrome. About half of the male population with fragile X syndrome has a heart murmur due to an improperly closed valve, a condition called mitral valve prolapse. Seizures, lazy eye, hernias, joint problems, depression, dysplasia, scoliosis, and flat feet are other complications and medical problems that can affect individuals with fragile X. Medical check-ups should be regular, as this can prevent and cure in the most effective way.