Dorsal premotor cortex and conditional movement selection: A PET functional mapping study.
Dorsal premotor cortex and conditional movement selection: A PET functional mapping study.
复制标题
DOI：
10.3902/jnns.5.78
复制
发表时间：
1998
影响因子：
2.5
通讯作者：
Scott T. Grafton;A. Fagg;M. Arbib
中科院分区：
文献类型：
--
作者：
Scott T. Grafton;A. Fagg;M. Arbib
正电子发射断层扫描（PET）脑映射被用来研究是否背侧运动前皮层参与选择运动行为的基础上任意的视觉刺激。正常受试者进行四个动作选择任务。使用具有三个可抓握站的操作器。一个强制性的视觉提示（LED灯以随机顺序点亮）指示下一个要抓住的站，没有指示延迟期。在动力任务中，所有试验均使用大孔径动力握把，与LED颜色无关。在精确任务中，使用拇指和食指的钳形抓握。在条件任务中，抓握的类型（力量或精度）由LED颜色随机确定。条件选择任务与平均功率和精度任务的比较显示，左背运动前皮质和上级顶叶小叶的血流量增加。产生不同抓取类型和运输到操作台的平均速率在该比较中是相等的，最小化运动属性的贡献，例如规划个体运动（与使用指导刺激相关的规划不同）、运动学或目标或肢体运动的方向。所有三个运动任务与休息任务的比较确定了涉及大面积的中央，中央前和中央后皮质的运动相关活动。在该地区的中央前沟运动相关的活动位于紧接尾部的区域在选择过程中激活。结果建立了人类背侧运动前皮层和上级顶叶皮层在选择刺激引导运动的作用，并建议背侧运动前皮层内的功能隔离。
Positron emission tomography (PET) brain mapping was used to investigate whether or not human dorsal premotor cortex is involved in selecting motor acts based on arbitrary visual stimuli. Normal subjects performed four movement selection tasks. A manipulandum with three graspable stations was used. An imperative visual cue (LEDs illuminated in random order) indicated which station to grasp next with no instructional delay period. In a power task, a large aperture power grip was used for all trials, irrespective of the LED color. In a precision task, a pincer grasp of thumb and index finger was used. In a conditional task, the type of grasp (power or precision) was randomly determined by LED color. Comparison of the conditional selection task versus the average of the power and precision tasks revealed increased blood flow in left dorsal premotor cortex and superior parietal lobule. The average rate of producing the different grasp types and transport to the manipulandum stations was equivalent across this comparison, minimizing the contribution of movement attributes such as planning the individual movements (as distinct from planning associated with use of instructional stimuli), kinematics, or direction of target or limb movement. A comparison of all three movement tasks versus a rest task identified movement related activity involving a large area of central, precentral and postcentral cortex. In the region of the precentral sulcus movement related activity was located immediately caudal to the area activated during selection. The results establish a role for human dorsal premotor cortex and superior parietal cortex in selecting stimulus guided movements and suggest functional segregation within dorsal premotor cortex.