Neural mechanisms for suppression of saccades by the frontal eye field

额叶视野抑制眼跳的神经机制

• 批准号: 16300131
• 负责人: SHINODA Yoshikazu
• 金额: $ 6.91万
• 依托单位: Tokyo Medical and Dental University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16300131/
• 关键词: frontal eye field; saccade; fixation; smooth pursuit eye movement; frontal eye field; saccade; fixation; smooth pursuit eye movement

To understand the neural mechanism of fixation, we investigated effects of electrical stimulation of the frontal eye field (FEF) and its vicinity on visually guided (Vsacs) and memory-guided saccades (Msacs) in trained monkeys and found that there were two types of suppression induced by the electrical stimulation : suppression of ipsilateral saccades and suppression of bilateral saccades. In this report, we characterized the properties of the suppression of bilateral Vsacs and Msacs. Stimulation of the bilateral 'suppression sites suppressed the initiation of both Vsacs and Msacs in all directions during and 〜50ms after stimulation but did not affect the vector of these saccades. The suppression was stronger for ipsiversive larger saccades and contraversive smaller saccades, and saccades with initial eye positions shifted more in the saccadic direction. The most effective stimulation timing for the suppression of ipsilateral and contralateral Vsacs was 〜40-50ms before saccade onset, indicating that the suppression occurred most likely in the superior colliculus and/or the paramedian pontine reticular formation. Suppression sites of bilateral saccades were located in the prearcuate gyrus facing the inferior arcuate sulcus where stimulation induced suppression at 【less than or equal】40μA but usually did not evoke any saccades at 80μA and were different from those of ipsilateral saccades where stimulation evoked saccades at 【less than or equal】50μA The smooth pursuit area of the FEF was different from the bilateral suppression area. The bilateral suppression sites contained fixation neurons. The results suggest that fixation neurons in the bilateral suppression area of the FEF may play roles in maintaining fixation by suppressing saccades in all directions.

To understand the neural mechanism of fixation, we investigated effects of electrical stimulation of the frontal eye field (FEF) and its vicinity on visually guided (Vsacs) and memory-guided saccades (Msacs) in trained monkeys and found that there were two types of suppression induced by the electric stimulation: suppression of ipsilateral saccades and suppression of bilateral saccades.在本报告中，我们表征了双侧VSAC和MSAC抑制的特性。双侧抑制位点的刺激抑制了VSAC和MSAC在刺激后的各个方向和〜50ms的主动性，但不影响这些扫视的载体。对于较大的扫视和矛盾的较小的扫视，抑制更强，并且具有初始眼睛位置的扫视沿扫视方向变化更多。抑制同侧和对侧VSAC的最有效刺激时间是扫视发作前约40-50ms，这表明抑制最有可能发生在上丘和/或parledian pontine网状网状形成中。 Suppression sites of bilateral saccades were located in the prearcuate gyrus facing the inferior arcuate sulcus where stimulation induced suppression at [less than or equal] 40μA but usually did not evoke any saccades at 80μA and were different from those of ipsilateral saccades where stimulation evoked saccades at [less than or equal] 50μA The smooth pursuit area of​​ ​​the FEF was different from the双侧抑制区。双侧抑制位点包含固定神经元。结果表明，FEF双侧抑制区域中的固定神经元可能通过抑制各个方向的扫视来保持固定作用。