The genetic contribution to the variance in the size of brain regions for typical neurodevelopment across the lifespan is high (for review, see (Kremen et al. 2010; Peper et al. 2007; Schmitt et al. 2007; Blokland et al. 2012)). Among these studies, heritability values for regional structures were generally more variable and lower than global indices. In adults, additive genetic influences accounted for 40-75% of the total variance for different neuroanatomical measures. In general, there are few regions that have evidence of significant shared environmental effects (Peper et al. 2007; Schmitt et al. 2007; Baare et al. 2001; Geschwind et al. 2002; Glahn et al. 2007; Thompson et al. 2001), although lateral ventricular volume during childhood and adolescence may be an exception (Kremen et al. 2012).
