Vestibulo-ocular reflex (VOR) pathways were devided functionally into four parts as follows Sivna I transformation in each part was expounded using transfer function.(1) Head angular acceleration leads to the cupula displacement, which represents head angular velocity. The cupula displacement is transformed into increased or decreased firing rate of vestibular nerve.(2) The head velocity signal via the vestibular nerve is modified into the signal that approximates head velocity more accurately. This means that cupula time constant (Tc) is prolonged to longer VOR time constant (Tv) by the circuit including the neural integrator in the CNS.(3) The head velocity signal (time constant: Tv) is transformed into the eye position signal by the circuit including another neural integrator. Both the head velocity signal and the eve position signal are input to the oculomotor neurons.(4) To move the eye balls properly, the power against the viscous and elastic resistance in the orbit is necessary. They are proportional to the eye velocity and eye position, respectively. The head velocity signal and the eye position signal mentioned above correspond to these. Transfer function of whole VOR is the product of these four i. e. GVOR (S)(g: VOR gain, Tv: time constant of VOR).

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