The following behavioural tests were assessed in wt and NPC1nmf164 mice treated or not with 0.09mg/kg/day EFV D. Mean ± SEM percentage of entries in the novel arm of the Y maze test (n=10 mice, 10 week-old, 2-way ANOVA, ***p < 0.0001). E. Mean ± SEM percentage of freezing time in the Contextual Fear Conditioning test (n=10 mice, 10 week-old, 2-way ANOVA, **pNPC1 < 0.0025, *pNPC1+EFV < 0.0181). F. Mean ± SEM percentage of freezing time in the Cued Fear Conditioning test (n=10 mice, 10 week-old, 2-way ANOVA, *pNPC1 < 0.0453, **pNPC1+EFV < 0.0054). 