Figure 4

Effects of prenatal stress on ultrasonic communication in juvenile mice. Ultrasonic vocalizations (USVs) were assessed during the direct social interaction test with an adult NMRI WT female in Fmr1 mice of both sexes. The following parameters were measured through spectrographic analysis of the calls: total number (a,b), mean duration (c,d), mean peak frequency (e,f) and amplitude (g,h). The number of the calls was subjected to square-root (sqrt) transformation in order to meet the normality assumptions of parametric ANOVA. * p < 0.05. N for males: 10 (a,c,e,g) WT-no stress, 8 (a,c,e) and 7 (g) WT-stress, 8 (a,c,e) and 11 (g) KO-no stress, 10 (a,c,e,g) KO-stress; N for females: 11 (b,d,f,h) WT-no stress, 12 (b,d,f,h) WT-stress, 12 (b,d,f) and 11 (h) KO-no stress, 12 (b,d,f) and 11 (h) KO-stress. KO refers to -/Y in males, HET to +/− in females. Data are expressed as mean ± SEM.