Fig. 4

MPS IIIB mice exhibit altered responses to negative stimuli suggestive of reduced fear by early adulthood. A Weight measurements recorded during Acoustic Startle/PPI task. B Startle response to 120 dB acoustic stimulus across 4 trials. C Startle response to consecutive trials of acoustic stimuli presentations of increasing dB level. D Inhibition of startle response to 120 dB stimuli following prepulse tone 4, 8, or 16 dB above background. E Percent of mice per group that exhibited a significant difference in response between startle and non-startle trials. F Schematic of fear conditioning paradigm. G Percent time freezing during baseline and tone/shock conditioning on day one. H Percent time freezing in response to fear context on day two. I Percent time freezing on day three during baseline in a new context and during tone presentation. A, and G-I Grouped data are presented as means ± SEM with individual data points presented as open circles. B-D Grouped data are presented as covariate adjusted means ± SEM accounting for differences in body weight. E Data are presented as counts