Natural recovery from fear generalization without extinction training indicates that extinction of increased fear memory seems to be preserved in the CaMKIIα (K42R)-KI mouse, which does not fit as a PTSD model, because in PTSD, fear generalization is sustained and difficult to be extinguished (Siegmund and Wotjak, 2006; Yehuda and LeDoux, 2007). Here, CAMK2A is linked to post-traumatic stress disorder.