Paré M, Wurtz R H
Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
J Neurophysiol. 1997 Dec;78(6):3493-7. doi: 10.1152/jn.1997.78.6.3493.
The connection between the posterior parietal cortex (PPC) and the superior colliculus (SC) was investigated by antidromically activating neurons within the lateral intraparietal (LIP) area with single-pulse stimulation delivered to the intermediate layers of the SC. To dissociate visual and saccade-related responses, the discharge properties of the identified efferent neurons were studied in the delayed visually guided saccade task and the memory guided saccade task. We found that the great majority (74%) of the identified LIP efferent neurons have a peripheral visual receptive field, typically with a broad spatial tuning. About two-thirds (64%) exhibited sustained activity during the delay period of the behavioral tasks, during which the monkeys had to withhold eye movements, and 80% of these increased their activity just before the onset of saccades. Both delay and presaccadic discharges in the delayed visually guided saccade task were higher than in the memory guided saccade task. These results establish that the neuronal signal sent by LIP to the SC carries both visual and saccade-related information.
通过向中脑上丘（SC）中间层施加单脉冲刺激，逆向激活外侧顶内（LIP）区的神经元，研究了顶叶后皮质（PPC）与中脑上丘（SC）之间的联系。为了区分视觉和扫视相关反应，在延迟视觉引导扫视任务和记忆引导扫视任务中研究了已识别的传出神经元的放电特性。我们发现，绝大多数（74%）已识别的LIP传出神经元具有外周视觉感受野，通常具有广泛的空间调谐。约三分之二（64%）的神经元在行为任务的延迟期表现出持续活动，在此期间猴子必须抑制眼球运动，其中80%的神经元在扫视开始前活动增加。延迟视觉引导扫视任务中的延迟放电和扫视前放电均高于记忆引导扫视任务。这些结果表明，LIP向SC发送的神经元信号携带视觉和扫视相关信息。
