Developmental disabilities are considered to be lifelong, severe chronic cognitive and physical disabilities that that appear before the age of 22. Developmental disabilities include but are not limited to mild to severe mental retardation, auditory processing disorder, cerebral palsy, muscular dystrophy, fetal alcohol syndrome and Down’s syndrome.
Intellectual disabilities (include but are not limited to) Asperger’s Syndrome, Autism Spectrum Disorder (both are also known as Pervasive Developmental Disorder and Pervasive Developmental Disorder not otherwise specified) and Borderline Intellectual Disability (formerly Borderline Intellectual Functioning according to the DSM V).
Intellectual disabilities fall under the same definition of developmental disabilities due to the chronic cognitive nature of the diagnoses. Intellectual disabilities display significant limitations in intellectual functioning, adaptive behavior and have an onset before the age of 18.