Fig. 1.

Imbalance behaviors of Oc90 null mice as compared with other otoconia mutants. Statistical comparisons are presented in Table 1 and Fig. 2. (A) Delayed development of the air-righting response of Oc90 null mice (P11 shown). At this age, wt pups right their body positions instantly, and it is not possible to photograph the landing process. (C) Oc90 null pups (P16) hold their heads and bodies in a tilted position. Compared with wt mice (D), Oc90 null mice (F) walk with ataxic gaits that have irregular shorter strides, wider stances and a non-linear curved pattern compared with wt littermate controls. Homozygous Otop1^tlt (J) and Nox3^het (L) mice have worse ataxic gaits than Oc90 null mice. (G) Oc90 null pups sometimes walk in a circular pattern, i.e. when they are put in a new environment and become disoriented. Otop1^tlt (K) and Nox3^het (M) mice show worse circular patterns under the same conditions.