Center for Research in Cognition & Neuroscience (CRCN), Université Libre de Bruxelles, 1050 Brussels, Belgium.
Department of Psychology, Lancaster University, Lancaster LA1 4YF, UK.
Sensors (Basel). 2023 Jan 14;23(2):972. doi: 10.3390/s23020972.
Most well-established eye-tracking research paradigms adopt remote systems, which typically feature regular flat screens of limited width. Limitations of current eye-tracking methods over a wide area include calibration, the significant loss of data due to head movements, and the reduction of data quality over the course of an experimental session. Here, we introduced a novel method of tracking gaze and head movements that combines the possibility of investigating a wide field of view and an offline calibration procedure to enhance the accuracy of measurements. A 4-camera Smart Eye Pro system was adapted for infant research to detect gaze movements across 126° of the horizontal meridian. To accurately track this visual area, an online system calibration was combined with a new offline gaze calibration procedure. Results revealed that the proposed system successfully tracked infants' head and gaze beyond the average screen size. The implementation of an offline calibration procedure improved the validity and spatial accuracy of measures by correcting a systematic top-right error (1.38° mean horizontal error and 1.46° mean vertical error). This approach could be critical for deriving accurate physiological measures from the eye and represents a substantial methodological advance for tracking looking behaviour across both central and peripheral regions. The offline calibration is particularly useful for work with developing populations, such as infants, and for people who may have difficulties in following instructions.
大多数成熟的眼动追踪研究范式采用远程系统，这些系统通常具有有限宽度的常规平面屏幕。当前的眼动追踪方法在广泛的区域内存在局限性，包括校准、由于头部运动而导致的大量数据丢失，以及在实验过程中数据质量的降低。在这里，我们引入了一种新的追踪注视和头部运动的方法，它结合了调查广阔视野的可能性和离线校准程序，以提高测量的准确性。我们将 4 个摄像头的 Smart Eye Pro 系统应用于婴儿研究中，以检测水平子午线 126°范围内的注视运动。为了准确地追踪这个视觉区域，我们将在线系统校准与新的离线注视校准程序相结合。结果表明，该系统成功地追踪了婴儿的头部和注视，超出了平均屏幕尺寸。离线校准程序的实施通过纠正系统的右上角误差（平均水平误差 1.38°，平均垂直误差 1.46°），提高了测量的有效性和空间准确性。这种方法对于从眼睛中得出准确的生理测量值非常重要，代表了在中央和周边区域追踪注视行为的重要方法学进展。离线校准对于婴儿等发育中人群的工作以及可能难以遵循指令的人群特别有用。
