BDNF and autism spectrum disorder: Furthermore, BDNF levels in preterm neonates differ from BDNF levels in full-term neonates (Malamitsi-Puchner et al. 2004), thereby affecting cognitive development in early postnatal life (Chau et al. 2017) and potentially being associated with children’s mental diseases such as autism spectrum disorders (Qin et al. 2016; Zheng et al. 2016).