OBJECTIVE
To review the literature over the past decade on mental retardation, particularly as regards its definition, prevalence, major causes, and associated mental disorders.
METHOD
A computerized search was performed for articles published in the past decade, and selected papers were highlighted.
RESULTS
The study of mental retardation has benefited considerably by advances in medicine generally and by developments in molecular neurobiology in particular. Increasing awareness of psychiatric comorbidity in the context of intellectual disability highlights the need for studies of the phenomenology and treatment of mental disorders in this population.
CONCLUSIONS
Although the study of developmental disorders has advanced significantly over the past decade, considerable work remains. Mental retardation is a model for the utility of the biopsychosocial approach in medicine.