Table 1.
Milestones of Neuroanatomical and Neurobehavioral Vestibular Development in Mouse (Mus musculus) and Rat (Rattus norvegicus)
| Mouse embryonic age | Rat embryonic age | Rat gestational age | Developmental milestone |
|---|---|---|---|
| 9-13a | 11-15 (Altman & Bayer, 1980) | G11.5-15.5 | Differentiation of neurons within vestibular nuclei |
| 9.5 (Theiler, 1989; Sher, 1971) | 11.5 (Altman & Bayer, 1982) | G12 | Formation of otocyst |
| 10-12 (Ruben, 1967) | 12-14 (Altman & Bayer, 1982) | G13.5-14.5 | Formation of vestibular (otic) ganglion cells |
| 10.5 (Sher, 1971; Tello, 1931) | 13 (Ashwell & Zhang, 1998) | G13.5 | Afferent processes of vestibular ganglion cells invade the macula utricle and saccule and cristae of the semicircular canals |
| 11-12 (Fritzsch & Nichols, 1993) | 13-14a | G13.5-14.5 | Efferent nerve endings first approach hair cells |
| 13-17 (Ruben, 1967) | 15-19 (Altman & Bayer, 1980) | G15.5-19.5 | Peak hair cell mitosis in crista ampullaris, maculae of saccules, and utricles |
| 15 (Mbiene, Favre, & Sans, 1988) | 17a | G17.5 | Afferent synaptogenesis with hair cells begins |
| 18-P10 (Rusch, Lysakowski, & Eatock, 1998) | 20-P12a | G20.5-P12 | Morphological differentiation into Type I and Type II hair cells |
| P28 (Rusch, Lysakowski, & Eatock, 1998) | P30a | P30 | Fully mature morphological and physiological innervation |
Note. G = gestational age (days); P = postnatal age (days).
a
Data not available in either mouse or rat, so the approximate age is estimated based on data from the other species.