Vrijling A C L, de Boer M J, Renken R J, Marsman J B C, Grillini A, Petrillo C E, Heutink J, Jansonius N M, Cornelissen F W
Laboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands; Royal Dutch Visio, Centre of Expertise for Blind and Partially Sighted People, Huizen, the Netherlands.
Laboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
Vision Res. 2023 Apr;205:108188. doi: 10.1016/j.visres.2023.108188. Epub 2023 Feb 9.
Human observers tend to naturally track moving stimuli. This tendency may be exploited towards an intuitive means of screening visual function as an impairment induced reduction in stimulus visibility will decrease tracking performance. Yet, to be able to detect subtle impairments, stimulus contrast is critical. If too high, the decrease in performance may remain undetected. Therefore, for this approach to become reliable and sensitive, we need a detailed understanding of how age, stimulus contrast, and the type of stimulus movement affect continuous tracking performance. To do so, we evaluated how well twenty younger and twenty older participants tracked a semi-randomly moving stimulus (Goldmann size III, 0.43 degrees of visual angle), presented at five contrast levels (5%-10%-20%-40%-80%). The stimulus could move smoothly only (smooth pursuit mode) or in alternation with displacements (saccadic pursuit mode). Additionally, we assessed static foveal and peripheral contrast thresholds. For all participants, tracking performance improved with increasing contrast in both pursuit modes. To reach threshold performance levels, older participants required about twice as much contrast (20% vs. 10% and 40% vs. 20% in smooth and saccadic modes respectively). Saccadic pursuit detection thresholds correlated significantly with static peripheral contrast thresholds (rho = 0.64). Smooth pursuit detection thresholds were uncorrelated with static foveal contrast thresholds (rho = 0.29). We conclude that continuous visual stimulus tracking is strongly affected by stimulus contrast, pursuit mode, and age. This provides essential insights that can be applied towards new and intuitive approaches of screening visual function.
人类观察者往往会自然地追踪移动的刺激物。这种倾向可被用于一种直观的视觉功能筛查方法，因为由损伤引起的刺激物可见度降低会降低追踪性能。然而，为了能够检测到细微的损伤，刺激物对比度至关重要。如果对比度太高，性能的下降可能无法被检测到。因此，为了使这种方法变得可靠且灵敏，我们需要详细了解年龄、刺激物对比度和刺激物运动类型如何影响连续追踪性能。为此，我们评估了20名年轻参与者和20名年长参与者在五个对比度水平（5%-10%-20%-40%-80%）下追踪一个半随机移动的刺激物（戈德曼III号大小，视角0.43度）的能力。刺激物可以仅平滑移动（平滑追踪模式）或与位移交替移动（扫视追踪模式）。此外，我们评估了静态中央凹和周边对比度阈值。对于所有参与者，在两种追踪模式下，追踪性能都随着对比度的增加而提高。为了达到阈值性能水平，年长参与者所需的对比度大约是年轻参与者的两倍（在平滑模式和扫视模式下分别为20%对10%和40%对20%）。扫视追踪检测阈值与静态周边对比度阈值显著相关（rho = 0.64）。平滑追踪检测阈值与静态中央凹对比度阈值不相关（rho = 0.29）。我们得出结论，连续视觉刺激追踪受到刺激物对比度、追踪模式和年龄的强烈影响。这为可应用于新型直观视觉功能筛查方法的研究提供了重要见解。
