Figure 1: Impaired fear extinction precedes memory decline in Fmn2 mutant mice.F. Freezing was analyzed in 3- (n=11), 12- (n=9) and 16- (n=8) month old male wild type mice. A significant impairment (P < 0,0001) was observed in 16-month old animals when compared to either 3- or 12-month old animals. 