Recent studies clearly indicate that PDE2 inhibitors can regulate neuronal plasticity, reduce tau phosphorylation and beta amyloid (Aβ) aggregation, promote inflammatory cytokines and apoptosis, increase the levels of Brain-Derived Neurotrophic Factor (BDNF) and cAMP/cGMP, and improve cognitive impairment [11,12,13,14]. This evidence concerns the gene BDNF and Cognitive impairment.