What are the different types of developmental disabilities?
Nervous system disabilities These are birth defects that affect the functioning of the brain, spinal cord, and nervous system, which can impact intelligence and learning. These conditions can also cause problems such as behavioral disorders, speech or language difficulties, convulsions, and movement disorders. Some of the common nervous system disabilities include: • Mental retardation – The term mental retardation describes a certain range of scores on an IQ (intelligence quotient) test. Mental retardation can result from a number of different conditions, including (but not limited to): • [down_syndrome.cfm Down syndrome] – a set of mental and physical characteristics related to having an extra copy of Chromosome 21. • [fragile_x_syndrome.cfm Fragile X syndrome]- the most common inherited form of mental retardation caused by a defect in a specific part of the Fragile X Mental Retardation-1 gene that causes the body to produce low amounts or none of a certain protein. Without the prote
