Terao Yasuo, Fukuda Hideki, Tokushuge Shinnichi, Nomura Yoshiko, Hanajima Ritsuko, Ugawa Yoshikazu
Department of Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Segawa Neurological Clinic for Children, Japan.
Clin Neurophysiol. 2016 Aug;127(8):2953-2967. doi: 10.1016/j.clinph.2015.07.041. Epub 2015 Sep 30.
To study saccade abnormalities associated with focal cerebral lesions, including the cerebral cortex and basal ganglia (BG).
We studied the latency and amplitude of reflexive and voluntary saccades in 37 patients with focal lesions of the frontal and parietal cortices and BG (caudate and putamen), and 51 age-matched controls, along with the ability to inhibit unwanted reflexive saccades.
Latencies of reflexive saccades were prolonged in patients with parietal lesions involving the parietal eye field (PEF), whereas their amplitude was decreased with parietal or putaminal lesions. In contrast, latency of voluntary saccades was prolonged and their success rate reduced with frontal lesions including the frontal eye field (FEF) or its outflow tract as well as the dorsolateral/medial prefrontal cortex, and caudate lesions, whereas their amplitude was decreased with parietal lesions. Inhibitory control of reflexive saccades was impaired with frontal, caudate and, less prominently, parietal lesions.
PEF is important in triggering reflexive saccades, also determining their amplitude. Whereas FEF and the caudate emit commands for initiating voluntary saccades, their amplitude is mainly determined by PEF. Commands not only from FEF and dorsolateral/medial prefrontal cortex but also from the caudate and PEF serve to inhibit unnecessary reflexive saccades.
The findings suggested how cortical and BG commands shape reflexive and voluntary saccades in humans.
研究与局灶性脑损伤相关的扫视异常，包括大脑皮层和基底神经节（BG）。
我们研究了37例额叶、顶叶皮质和BG（尾状核和壳核）局灶性损伤患者以及51名年龄匹配的对照者的反射性和自主性扫视的潜伏期和幅度，以及抑制不必要反射性扫视的能力。
累及顶叶眼区（PEF）的顶叶损伤患者的反射性扫视潜伏期延长，而顶叶或壳核损伤时其幅度减小。相比之下，包括额叶眼区（FEF）或其传出通路以及背外侧/内侧前额叶皮质的额叶损伤以及尾状核损伤患者的自主性扫视潜伏期延长且成功率降低，而顶叶损伤时其幅度减小。额叶、尾状核损伤以及不太明显的顶叶损伤会损害对反射性扫视的抑制控制。
PEF在触发反射性扫视中很重要，也决定其幅度。而FEF和尾状核发出启动自主性扫视的指令，其幅度主要由PEF决定。不仅来自FEF和背外侧/内侧前额叶皮质，而且来自尾状核和PEF的指令都有助于抑制不必要的反射性扫视。
这些发现提示了皮质和BG指令如何塑造人类的反射性和自主性扫视。
