Both typical (haloperidol) and atypical antipsychotic drugs (clozapine, risperidone) decrease serum BDNF levels in schizophrenia patients (Xiu et al., 2009) and the expression of Bdnf mRNA in the hippocampus of rats (Angelucci et al., 2000; Lipska et al., 2001; Chlan-Fourney et al., 2002) although results are inconsistent in some studies (Bai et al., 2003; Park et al., 2011a). Here, BDNF is linked to schizophrenia.