Despite decades of research, mental retardation remains an amorphous concept defined not in black and white but in ever-changing shades of gray. As recently as 40 years ago, the condition was defined ...

What's in a name? For people served by the Massachusetts Department of Mental Retardation and their families and friends, this is a very important question. The label "mental retardation" is part of a ...

The International Classification of Diseases, or ICD, is a classification system for all physical and mental diseases produced by the World Health Organization (WHO). It’s used for diagnosis, research ...

Since average scores on particular IQ tests rise a few points every 3 or 4 years, those tests become obsolete after a couple of decades. In order to reset the average score to 100, harder IQ tests are ...

The human brain is a highly complex structure, and its normal development and functioning is critically dependent on the proper and tightly regulated activity of a large number of genes. Indeed, ...

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of ...