Transient deviation of closed eye on head torsion. A kind of neck-ocular reflex

Electrooculographically, torsion of the head with closed eyes causes little appearance of VOR, but a transient ocular deviation (TOD) of about 30 degrees and a maximum velocity of not less than 200 degrees/sec. TOD occurs more significantly during torsion of the head alone than during rotation of the whole body, with a two-fold greater degree of deviation, suggesting the importance of the input from the cervical afferent. TOD occurs even in a condition in which torsion of the head is made to try with the head fixed and as a result of this maneuver, a torsional force is put on the neck toward the direction of head torsion, but the head does not rotate (vestibular afferent is inoperative). Thus, it is supposed that TOD occurs as a result of the fact that the lateral gaze center is activated by perception of the directional information of head torsion from the cervical afferent.