Hooge Ignace, Holmqvist Kenneth, Nyström Marcus
Experimental Psychology, Helmholtz Institute, Utrecht University, Heidelberglaan 1, 3584 CS Utrecht, The Netherlands.
Lund University Humanities Lab, Lund University, Helgonabacken 12, 22362 Lund, Sweden; School of Languages and Academic Literacy, Vaal Triangle Campus, North-West University, Vanderbijlpark 1900, South Africa.
Vision Res. 2016 Nov;128:6-18. doi: 10.1016/j.visres.2016.09.002. Epub 2016 Sep 22.
Most modern video eye trackers use the p-CR (pupil minus CR) technique to deal with small relative movements between the eye tracker camera and the eye. We question whether the p-CR technique is appropriate to investigate saccade dynamics. In two experiments we investigated the dynamics of pupil, CR and gaze signals obtained from a standard SMI Hi-Speed eye tracker. We found many differences between the pupil and the CR signals. Differences concern timing of the saccade onset, saccade peak velocity and post-saccadic oscillation (PSO). We also obtained that pupil peak velocities were higher than CR peak velocities. Saccades in the eye trackers' gaze signal (that is constructed from p-CR) appear to be excessive versions of saccades in the pupil signal. We conclude that the pupil-CR technique is not suitable for studying detailed dynamics of eye movements.
大多数现代视频眼动仪使用瞳孔减去角膜反射（p-CR）技术来处理眼动仪摄像头与眼睛之间的微小相对运动。我们质疑p-CR技术是否适用于研究扫视动力学。在两个实验中，我们研究了从标准的SMI高速眼动仪获得的瞳孔、角膜反射和注视信号的动力学。我们发现瞳孔信号和角膜反射信号之间存在许多差异。这些差异涉及扫视起始时间、扫视峰值速度和扫视后振荡（PSO）。我们还发现瞳孔峰值速度高于角膜反射峰值速度。眼动仪注视信号（由p-CR构建）中的扫视似乎是瞳孔信号中扫视的过度版本。我们得出结论，瞳孔-角膜反射技术不适用于研究眼动的详细动力学。
