Ebata S, Sugiuchi Y, Izawa Y, Shinomiya K, Shinoda Y
Department of Orthopedics, Graduate School of Medicine, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo 113, Japan.
Neurosci Res. 2004 May;49(1):55-68. doi: 10.1016/j.neures.2004.01.012.
Vestibular inputs to the cerebral cortex are important for spatial orientation, body equilibrium, and head and eye movements. We examined vestibular input to the periarcuate cortex in the Japanese monkey by analyzing laminar field potentials evoked by electrical stimulation of the vestibular nerve. Laminar field potential analysis in the depths of the cerebral cortex showed that vestibular-evoked potentials consisted of early-positive and late-negative potentials and early-negative and late-positive potentials in the superficial and deep layers of the periarcuate cortex, respectively, with latencies of 4.8-6.3 ms, suggesting that these potentials were directly conveyed to the cortex through the thalamus. These potentials were distributed continuously in the fundus, dorsal and ventral banks of the spur and the bottom of the junctional part of the arcuate sulcus and spur. This vestibular-projecting area overlapped the cortical distribution of corticovestibular neurons that were retrogradely labeled by tracer injection into the vestibular nuclei (previously reported area 6 pa), and also the distribution of smooth pursuit-related neurons recorded in the periarcuate cortex including area 8 in a trained monkey. These results are discussed in relation to the function of vestibular information in control of smooth pursuit and efferents of the smooth pursuit-related frontal eye field.
前庭向大脑皮层的输入对于空间定向、身体平衡以及头部和眼睛运动非常重要。我们通过分析前庭神经电刺激诱发的层状场电位，研究了日本猕猴弓状周围皮层的前庭输入。大脑皮层深处的层状场电位分析表明，前庭诱发电位在弓状周围皮层的浅层和深层分别由早期正向和晚期负向电位以及早期负向和晚期正向电位组成，潜伏期为4.8 - 6.3毫秒，这表明这些电位是通过丘脑直接传至皮层的。这些电位连续分布于脑底、胼胝体的背侧和腹侧以及弓状沟与胼胝体交界处的底部。这个前庭投射区与通过向前庭核注射示踪剂逆行标记的皮质前庭神经元的皮质分布（先前报道的6区pa）重叠，也与在训练过的猕猴的弓状周围皮层（包括8区）记录到的与平稳跟踪相关的神经元的分布重叠。结合前庭信息在平稳跟踪控制中的功能以及与平稳跟踪相关的额叶眼区的传出神经，对这些结果进行了讨论。
