Effect of the number of response alternatives on brain activity in response selection
Effect of the number of response alternatives on brain activity in response selection
复制标题
反应选择中反应选项数量对大脑活动的影响
作者：
S. Woo;Kyoung
众所周知，在运动控制文献中，响应时间（RT）作为响应选择数（NA）的对数函数增加（希克定律）。在这项研究中，我们使用事件相关的功能性MRI和选择手指运动任务来确定这种关系的神经相关性。在行为上，所有受试者的平均RT增加作为NA的对数函数，按照法律。通过逐体素搜索活动与NA和RT相关的脑区，在后扣带回和左侧上级额回发现正相关，而在双侧顶下小叶区域观察到负相关。这种差异调制的任务背景下，即NA可用于选择反应相同的刺激和反应，表明这些区域参与了反应选择，故意检索的运动程序，或空间期望的各个方面。Brain Mapp 2006.© 2006 Wiley利斯公司
It is well‐known in motor control literature that a response time (RT) increases as a logarithmic function of the number of response alternatives (NA) (Hick's law). In this study, we identified neural correlates for this relationship using event‐related functional MRI and a choice finger‐movement task. Behaviorally, average RTs of all subjects increased as a logarithmic function of the NA in accordance with the law. From a voxel‐wise search for brain areas where the activity was correlated with NA and thence the RT, a positive correlation was found at the posterior cingulate and left superior frontal gyri, whereas a negative correlation was observed at areas in bilateral inferior parietal lobules. This differential modulation by the task context, namely, the NA available for a choice response with identical stimulus and response, indicates that these regions are involved in various aspects of response selection, intentional retrieval of motor program, or spatial expectancy. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.