Activity-dependent modulation: a non-linearity in the unilateral vestibulo-ocular reflex pathways.
Activity-dependent modulation: a non-linearity in the unilateral vestibulo-ocular reflex pathways.
复制标题
活动依赖性调节：单侧前庭眼反射通路的非线性。
DOI：
10.1007/s00221-005-2304-z
复制
发表时间：
2005
影响因子：
2
通讯作者：
Fong,Alexander
中科院分区：
文献类型：
--
作者：
Zhou,Wu;Simpson,Ivra;Xu,Youguo;Fong,Alexander
It is well established that the vestibulo-ocular reflex (VOR) depends not only on sensory stimulation but also on the behavioral context associated with the stimulation. Recent modeling studies suggested that including a non-linearity in the activation function of the VOR neurons achieves the desired context-dependence for the VOR without resorting to currently assumed complex cortical computations. With the non-linearity, neurons operate as non-linear summers of incoming activity with sensitivities modulated by their activation levels. In this study we examined whether such a non-linearity exists in the unilateral VOR pathways in behaving monkeys. Acoustic clicks were employed to evoke unilateral VOR responses during fixation, head motion and smooth pursuit. We found that the click-evoked unilateral VOR responses did not simply sum in a linear manner with the eye movements initiated by head or target motion. Instead, the same acoustic click evoked larger eye movements if the ongoing eye movements were in the same direction. We also showed that the interaction between the ongoing eye movement and the click-evoked response was close to being multiplicative. These results revealed a previous unknown non-linearity in the unilateral VOR pathways, which may have important implications on the neural implementation of the context-dependence for the VOR.
