Down syndrome: cognitive phenotype

Ment Retard Dev Disabil Res Rev. 2007;13(3):228-36. doi: 10.1002/mrdd.20156.


Down syndrome is the most prevalent cause of intellectual impairment associated with a genetic anomaly, in this case, trisomy of chromosome 21. It affects both physical and cognitive development and produces a characteristic phenotype, although affected individuals vary considerably with respect to severity of specific impairments. Studies focusing on the cognitive characteristics of Down syndrome were reviewed, and while performance in most areas could be predicted based upon overall intellectual disability, relative weaknesses were consistently found to be associated with expressive language, syntactic/morphosyntactic processing, and verbal working memory. This profile of uneven deficits could result from a failure to develop typically automatic processing for speech perception and production, and this possibility is discussed along with its implications for intervention.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Chromosomes, Human, Pair 21*
  • Cognition*
  • Down Syndrome / genetics
  • Down Syndrome / physiopathology
  • Down Syndrome / psychology*
  • Humans
  • Language*
  • Memory*
  • Phenotype
  • Verbal Learning