Extended Data Fig. 7: Control experiments for firing properties of CA2 neurons in Df(16)A+/− mice.
a,b, Saline injection (control for spadin injection) in Df(16)A+/− mice did not alter CA2 (a) mean firing rate (two-sided paired t-test p = 0.21) or (b) spatial stability in the five sessions of the three-chamber task (two-sided paired t-test, p = 0.31; n = 128 neurons). c, CA2 neuron firing rate in saline-injected Df(16)A+/− mice did not differ in interaction zone around the novel compared to familiar mouse (two-sided paired t-test, p = 0.7), similar to uninjected Df(16)A+/− mice (Fig. 7a) but distinct from CA2 novel firing preference in wild-type mice (Fig. 4c) and spadin-injected Df(16)A+/− mice (Fig. 7d). d–f, CA2 neuron firing properties in two groups of wild-type control mice used for comparison with Df(16)A+/− mice (all on identical C57Bl/6 J backgrounds): wild-type littermates of Df(16)A+/− mice (n = 56 neurons from 2 mice) and wild-type non-littermates (n = 136 neurons from 4 mice). d, There was no significant difference in mean firing rate between wild-type non-littermates (WT) and wild-type littermates (LM) (paired t-test, p = 0.19). e, CA2 spatial stability was slightly but significantly lower in wild-type littermates compared to wild-type non-littermates (two-sided paired t-test with Bonferroni correction, p = 0.002); spatial stability of both wild-type groups was significantly less than that of Df(16)A+/− mice (two-sided paired t-test with Bonferroni correction, p < 0.0001 in both cases). f, The two wild-type control groups did not differ in their increase in firing around the novel compared to familiar animal (two-sided paired t-test, p = 0.45). Box plots display the center line as the mean; box limits are upper and lower quartiles; whiskers show min to max values in data sets. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.
