AKT1 and memory impairment: For example, Arcego et al. (2016) demonstrated that rats exposed to 7 days of social isolation showed memory impairment and reduced BDNF, Na+, K+, ATPase activity, MAPK, AKT and phospho-AKT levels in PFCx; however, rats exposed to this stress situation but fed with HFD showed restored memory impairment as well as the aforementioned biochemical alterations.