Haworth Joshua L, Vallabhajosula Srikant, Stergiou Nicholas
Nebraska Biomechanics Core Facility, University of Nebraska at Omaha, Omaha, NE, 68182-0216, USA,
Exp Brain Res. 2014 Sep;232(9):2797-806. doi: 10.1007/s00221-014-3962-5. Epub 2014 May 4.
In this study, we explored whether gaze and posture would exhibit coordination with the motion of a presented visual stimulus, specifically with regard to the complexity of the motion structure. Fourteen healthy adults viewed a set of four visual stimulus motion conditions, in both self-selected and semi-tandem stance, during which the stimulus moved horizontally across a screen, with position updated to follow a sine, chaos, surrogate, or random noise trajectory. Posture was measured using a standard force platform in self-selected and semi-tandem stance conditions while gaze was recorded using image-based eye-tracking equipment. Cross-correlation confirmed the continuous coordination of gaze with each type of stimulus motion, with increasing lag as stimulus motion complexity increased. Correlation dimension and approximate entropy were used to assess the complexity of the measured gaze and posture behaviors, with these values compared against those of the actual stimulus via ANOVA and dependent t tests. We found that gaze behavior was particularly sensitive to the complexity of the stimulus motion, according to both metrics. Posture seemed to be unaffected by stimulus motion viewing; however, different stance conditions did exhibit differences in posture metrics. Our results support an evolving understanding of how vision is used for determining perception and action.
在本研究中，我们探究了注视和姿势是否会与呈现的视觉刺激的运动表现出协调性，特别是在运动结构的复杂性方面。14名健康成年人在自选站姿和半串联站姿下观看了一组四种视觉刺激运动条件，在此期间，刺激物在屏幕上水平移动，其位置更新以遵循正弦、混沌、替代或随机噪声轨迹。在自选和半串联站姿条件下，使用标准测力平台测量姿势，同时使用基于图像的眼动追踪设备记录注视情况。互相关分析证实了注视与每种类型的刺激运动持续协调，随着刺激运动复杂性的增加，滞后增加。使用关联维数和近似熵来评估所测量的注视和姿势行为的复杂性，并通过方差分析和配对t检验将这些值与实际刺激的值进行比较。我们发现，根据这两种指标，注视行为对刺激运动的复杂性特别敏感。姿势似乎不受刺激运动观看的影响；然而，不同的站姿条件在姿势指标上确实表现出差异。我们的结果支持了对视觉如何用于确定感知和行动的不断发展的理解。
