Fig. 3: EphB2^+/− females, but not males, display deficits in cue-induced fear memory.

A Scheme representing the fear conditioning (FC) assay. During FC training, the animals are exposed to three footshocks (0.5 mA) preceded by an auditory tone (cue) in a specific chamber (context). Twenty-four hours later, during FC test, the animals are first placed in the same context, then placed in an altered context, and finally reexposed to the cue in the altered context. B EphB2^+/− males and females show normal context-induced fear memory (two-way ANOVA). C No difference in freezing time during the FC test in an altered context (two-way ANOVA). D EphB2^+/− females, but not males, display a robust decrease in freezing time when reexposed to the cue in an altered context (two-way ANOVA; significant interaction: p = 0.042; main effect of genotype: p = 0.007; post hoc analysis: for females, p = 0.0026, and for males, p = 0.8275). E No difference in freezing time during the last interval following the last footshock of fear conditioning training in the chamber between EphB2^+/− males or females and WT mice (two-way ANOVA). F EphB2^+/− females, but not males, present a statistical trend to decreased cue-induced freezing time during the last auditory tone of FC training, preceding the last footshock (two-way ANOVA; main effect of genotype: p = 0.0437; post hoc analysis: for females, p = 0.0616, and for males, p = 0.7272). G No difference in startle response to footshocks at 0.5 mA between EphB2^+/− and WT males and females (two-way ANOVA). WT wild type. Data are represented as mean ± SEM. Statistical significance was determined by two-way ANOVA with Sidak’s post hoc comparison. ^#p < 0.1, *p < 0.05, **p < 0.005, ns not significant. The number of animals is indicated in each bar for each experiment.