Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2011 Jun;9(6):e1001081.
doi: 10.1371/journal.pbio.1001081. Epub 2011 Jun 14.

Why are autism spectrum conditions more prevalent in males?

Simon Baron-Cohen  1 , Michael V Lombardo, Bonnie Auyeung, Emma Ashwin, Bhismadev Chakrabarti, Rebecca Knickmeyer
Affiliations
Review

Why are autism spectrum conditions more prevalent in males?

Simon Baron-Cohen et al. PLoS Biol. 2011 Jun.

Abstract

Autism Spectrum Conditions (ASC) are much more common in males, a bias that may offer clues to the etiology of this condition. Although the cause of this bias remains a mystery, we argue that it occurs because ASC is an extreme manifestation of the male brain. The extreme male brain (EMB) theory, first proposed in 1997, is an extension of the Empathizing-Systemizing (E-S) theory of typical sex differences that proposes that females on average have a stronger drive to empathize while males on average have a stronger drive to systemize. In this first major update since 2005, we describe some of the evidence relating to the EMB theory of ASC and consider how typical sex differences in brain structure may be relevant to ASC. One possible biological mechanism to account for the male bias is the effect of fetal testosterone (fT). We also consider alternative biological theories, the X and Y chromosome theories, and the reduced autosomal penetrance theory. None of these theories has yet been fully confirmed or refuted, though the weight of evidence in favor of the fT theory is growing from converging sources (longitudinal amniocentesis studies from pregnancy to age 10 years old, current hormone studies, and genetic association studies of SNPs in the sex steroid pathways). Ultimately, as these theories are not mutually exclusive and ASC is multi-factorial, they may help explain the male prevalence of ASC.

PubMed Disclaimer

Conflict of interest statement

The authors have declared that no competing interests exist.

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. A.P.A. DSM-IV diagnostic and statistical manual of mental disorders, 4th edition. Washington DC: American Psychiatric Association; 1994.
    1. Baird G, Simonoff E, Pickles A, Chandler S, Loucas T, et al. Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: the Special Needs and Autism Project (SNAP). Lancet. 2006;368:210–215. - PubMed
    1. Baron-Cohen S, Scott F. J, Allison C, Williams J. G, Bolton P, et al. Autism spectrum prevalence: a school-based U.K. population study. Brit J Psychiat. 2009;194:500–509. - PubMed
    1. Bauman M. L, Kemper T. L. Neuroanatomic observations of the brain in autism: a review and future directions. Int J Dev Neurosci. 2005;23:183–187. - PubMed
    1. Stodgell C. J, Ingram J. I, Hyman S. L. The role of candidate genes in unravelling the genetics of autism. Int Rev Res Ment Ret. 2001;23:57–81.

Publication types