BDNF and autism: Because BDNF/TrkB-mediated signaling pathways, including Akt-mTOR and Eps8-Rac, play a key role in the development of the cortex and in synaptic function and plasticity (Yoshii and Constantine-Paton 2010), altered BDNF/TrkB signaling through these pathways may be an important contributor to autism pathogenesis.