Age as a risk factor
In another study done by Cordner and Tamashiro, mice aged between young adult to 18 months were continuously exposed to stress stimulants for two weeks. While testing their memory, all mice have some cognitive impairment, but the old mice were much more affected throughout the testing as compared to the younger ones.
They also discovered that stress can cause the expression of beta-secretase or Bace1, a gene that also affects the plaques in the brain during Alzheimer’s disease. Young mice have Bace1 increased 1.5 up to 2 times in the hippocampus while in old mice, Bace1 doesn’t just affect the hippocampus but also the amygdala and prefrontal cortex which controls the thoughts, emotions, and actions.