4.1. Hippocampus
It has been shown that the hippocampus is asymmetric in children and adults without any sex effect (Jack CR et al., 1989; Szabo CA et al., 2001) In line with these findings, Thompson et al. have not found a sex difference in hippocampus symmetry neither in preterm nor in full-term neonates taking into consideration that hippocampal asymmetry develops during the gestational period and maintains into adulthood (Thompson DK et al., 2008; Thompson et al., 2009). This asymmetry has been suggested to be more pronounced in male children from 1 to 15 years old, than in their female counterparts (Pfulger T et al., 1999). It has been suggested that this sex-difference asymmetry is due to the influence of sex hormones, particularly testosterone (Lenroot RK and Giedd JN, 2010).