Mental retardation generally refers to pediatric mental retardation, which is characterized by slow mental development, poor levels of language development, and movement disorders. Pediatric mental retardation is a group of syndromes originating in children under the age of 18 with incomplete or impaired mental development, which is caused by a combination of both genetic and environmental components. Patients with pediatric mental retardation may exhibit varying degrees of mental retardation and social adjustment difficulties. Patients are less able than healthy children of the same age to speak, read and comprehend, do number crunching, exercise, and take care of themselves. Patients with mild mental retardation may show lower intellectual development, speaking and walking than children of the same age. Patients with moderate mental retardation may have a low level of language development and may not be able to express more complex content. In severe cases, patients may have slurred pronunciation or even be unable to speak. Some patients may be accompanied by symptoms such as movement disorders, seizures, and limb paralysis. Once a patient has a suspected case of pediatric mental retardation, he or she should go to the hospital to clarify the cause of the disease and be given targeted treatment.