Imai Akira, Tsuji Keiichiro
Department of Psychology, Faculty of Arts, Shinshu University, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
Vision Res. 2004 Apr;44(8):763-73. doi: 10.1016/j.visres.2003.10.021.
Event-related potentials were recorded from human subjects performing a visual detection task to find correlates of detection performance (d' and beta) in accordance with the theory of signal detection. Two spatial frequencies of square waves shifted horizontally with three shifting-step varieties were presented to the subjects who reported whether or not the waves were perceived to shift. Although three components of N1, P2, and P3 were observed for all of four response categories of hit, miss, false alarm, and correct rejection, only the amplitudes of the P3 component at vertex and parietal sites highly correlated to the detection sensitivity of d'. It was also found that coefficients of correlation between the P3 amplitudes at these sites and observed hit and false alarm rates were highly significant and a d'-extrapolation value reproduced by the normalized P3 amplitudes and the usual d' indicated a highly linear trend. Results suggest that generation of the P3 component is associated with "threshold-modulating" mechanisms which determine detection sensitivity of a task for each perceptual event.
从执行视觉检测任务的人类受试者身上记录事件相关电位，以根据信号检测理论找到检测性能（d'和β）的相关因素。向受试者呈现具有三种移位步长变化的水平移位的两种空间频率的方波，受试者报告是否感知到波发生了移位。尽管在命中、未命中、误报和正确拒绝这四个反应类别中均观察到了N1、P2和P3这三个成分，但仅头顶和顶叶部位的P3成分幅度与d'的检测灵敏度高度相关。还发现，这些部位的P3幅度与观察到的命中率和误报率之间的相关系数非常显著，并且由标准化P3幅度再现的d'外推值与通常的d'显示出高度线性趋势。结果表明，P3成分的产生与“阈值调节”机制有关，该机制决定了每个感知事件任务的检测灵敏度。
