In this study, over- and under- expression of BDNF in the HPC and PFC of WT and IL-4Rα┴ in infected groups results in depression-like behaviours and cognitive impairment which is similar to a report by Cunha et al., 2006, Sakata et al., 2010, Taliaz et al., 2010. The gene discussed is BDNF; the disease is depressive disorder.