Mental Retardation (MR) is diagnosed in individuals with an IQ below 70 who also have significant limitations in self-help skills. Causes of MR are numerous and can often be traced to genetics; prenatal conditions such as toxicity, infections, and trauma; birth complications; and postnatal medical conditions.
Problems in self-help skills are noticed far earlier than IQ deficits. Self-help skills are often referred to as adaptive functioning or adaptive living skills. You may encounter these terms in your child’s evaluation. They refer to your child’s ability to engage in the normal tasks of daily living and how well he can perform in comparison to others his own age.
The majority of children with Asperger’s Disorder have an average or higher than average IQ and thus are not likely to be misdiagnosed as MR. The deficits in self-help skills seen in MR are more widespread and the overall functioning is far below the child’s age. While children with Asperger’s Disorder do have deficits in self-help skills, they are quite scattered, with remarkable abilities in some areas and surprisingly limited skills in others. While most children with Asperger’s Disorder do not have MR, 75–80 percent of children with the other four types of PDD are also diagnosed with MR.