Fig. 1

High dietary zinc prevents auditory fear conditioning deficits in the heterozygous Tbr1^+/− mouse model of autism spectrum disorder (ASD). A Schematic of the auditory fear conditioning test. B Freezing responses of the wildtype Tbr1^+/+ mice (WT) and heterozygous Tbr1^+/− mice fed with the normal zinc diet (30 parts per million) before electric shock (Basal), immediately after the third electric shock (After Shock), and 1 day after training (Auditory Fear Memory) are shown. Tbr1^+/− mice (n = 14) display impaired auditory fear memory represented by significantly reduced freezing responses compared to WT (n = 12). C Tbr1^+/− mice (n = 12) fed with high dietary zinc (150 parts per million) no longer display significantly different freezing responses when compared to WT mice (n = 11). All data represent mean ± standard error of the mean, analysed using two-way analysis of variance (ANOVA) with Šídák's post hoc test and one-way ANOVA with Tukey’s post hoc test. ns = not significant, **p < 0.01