Compared to what? Early brain overgrowth in autism and the perils of population norms.

ABSTRACT:

Background

Early brain overgrowth (EBO) in autism spectrum disorder (ASD) is among the best replicated biological associations in psychiatry. Most positive reports have compared head circumference (HC) in ASD (an excellent proxy for early brain size) with well-known reference norms. We sought to reappraise evidence for the EBO hypothesis given 1) the recent proliferation of longitudinal HC studies in ASD, and 2) emerging reports that several of the reference norms used to define EBO in ASD may be biased toward detecting HC overgrowth in contemporary samples of healthy children.

Methods

Systematic review of all published HC studies in children with ASD. Comparison of 330 longitudinally gathered HC measures between birth and 18 months from male children with autism (n = 35) an

SUBMITTER: Raznahan A 

PROVIDER: S-EPMC4837958 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature