Neuronal mechanisms controlling the spatial attention and gaze movements

控制空间注意力和注视运动的神经机制

基本信息

批准号：
10480232
负责人：
ISA Tadashi
金额：
$ 7.87万
依托单位：
National Institute for Physiological Sciences
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

A substantial number of cholinergic projections originate from the parabrachial region in the midbrain the pedunculo-pontine tegmental nucleus(PPTN), and the latero-dorsal tegmental nucleus(LDTN). They are directed to several brain regions, icluding the lateral geniculate nusleus(LGN) of the thalamus, the superior colliculus(SC), dopamine neurons in substantia nigra, and the ponto-medullary reticular formation. Recent studies have suggested that the PPTN cholinergic neurons help control gating movements and attentive behaviors. To further clarify the function of the brainstem cholinergic system, we analyzed the single-unit activity of PPTN neurons in three awake Japanese monkeys while they were performing visually guided GAP/NO-GAP saccade tasks. About 64% (45/70) of the tested neurons exhibited a phasic change in their activity, which preceded their saccade-to-target : 26 cells had an increase in activity (burst-type cells), and 19 a decrease (pause-type cells). In addition to their presaccadic behavior, the burst neurons tended to show an increase in activity, and the pause cells a decrease, during the GAP period(i. e., the 200-ms blank period between the offset of the fixation point and onset of the saccade target). These results suggested that PPTN neurons are involved in the preparation for a saccade-to-target. Additionally, 7 neurons exhibited a tonic increase in their activity from the intertrial interval (the time between the reward in the preceding trial and onset of the fixation point in the succeeding trial) until the end of the saccade. Furthermore, 29 neurons had a tonic, and 5 a phasic, increase in activity when the fixation point first appeared. This latter behavior was closely correlated with the successful completion of the upcoming saccade-to-target, thereby suggesting that such neurons contribute to control of the animals' vigilance.

大量的胆碱能投影来自中脑的副型区域，pedunculo-pontine temental nucleus（PPTN）和后期偏向段核（LDTN）。它们针对多个大脑区域，占丘脑的侧向二核（LGN），上丘丘（SC），黑质尼格拉的多巴胺神经元和蓬托 - 金皮尔的网状形成。最近的研究表明，PPTN胆碱能神经元有助于控制门控运动和细心行为。为了进一步阐明脑干胆碱能系统的功能，我们在执行视觉引导的GAP/NO-NO-GAP扫视任务时分析了PPTN神经元在三只醒着的日本猴子中的单单位活性。大约64％（45/70）测试的神经元在其活性发生了阶段变化，在其扫视至靶标之前：26个细胞的活性增加（爆发型细胞）和19个降低（暂停型细胞）。除了它们的前行为外，爆发神经元还倾向于显示活动的增加，并且在间隙期间（即，在固定点偏移到扫视目标的偏移之间的200毫秒空白周期）降低。这些结果表明，PPTN神经元参与了扫视到靶标的准备。此外，有7个神经元从中间间隔（在先前的试验中的奖励与在接下来的试验中的固定点开始之间的奖励之间的时间）表现出滋补作用）直到扫视结束。此外，当固定点首次出现时，有29个神经元具有刺激性和5个阶段性，活动的增加。后一种行为与即将到来的扫视到靶的成功完成密切相关，从而表明这种神经元有助于控制动物的警惕性。