MAPT and post-traumatic stress disorder: Additionally, some of the cognitive deficits may be associated with increased tau protein deposition in the brain (Wei et al., 2019), specifically in SPS-induced PTSD rats, due to the incongruent interaction between AKT-related GSK-3β activation and SGK1-related ERK1/2 inactivation, which ultimately leads to hyperphosphorylation of tau proteins at the Ser202/Thr205 and Ser404 loci.