The overall body posture and movement is balanced by the integration of information received from the vestibular system (vestibule receptors), proprioceptors (somatic receptors) and visual receptors by the brain. The vestibular system is the localized somatosensory system.
The vestibular apparatus (and cochlea) present in the ear contains mechanoreceptors that respond to the sense of hearing and equilibrium.
Thus, the blanks can be filled with vestibular system; balance.