Perdziak Maciej, Gryncewicz Wojciech, Witkowska Dagmara, Sawosz Piotr, Ober Jan
Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw, Poland.
Laboratory of Vision Science and Optometry, Faculty of Physics, Adam Mickiewicz University, Poznan, Poland.
J Vis. 2019 Apr 1;19(4):17. doi: 10.1167/19.4.17.
Amblyopia is a neurodevelopmental vision disorder that is associated with abnormal visual stimulation during early childhood. Although our knowledge regarding spatial vision deficits in amblyopic subjects is well established, the neural control of eye movements in amblyopia is yet to be explored. In the present study we have evaluated the gap effect, and for the first time (to our best knowledge), express saccades generation in amblyopic (strabismic as well as anisometropic) and age-matched control subjects. We have compared the saccadic latency under different gap conditions ("no gap," 50 ms gap, and 200 ms gap), between the amblyopic and control groups. Our results have shown that saccadic latency was reduced during the gap paradigms both for amblyopic and control groups for all viewing conditions. Furthermore, the size of the gap effect was comparable for all groups and viewing conditions (both for short and long gap durations). In addition, consistent with previous results, the amblyopic eye has manifested an increased saccadic latency as compared to the nondominant eye in the control group. Regarding the occurrence of express saccades, the 200 ms gap condition was associated with an increased number of express saccades as compared to 50 ms gap and "no gap" conditions, both for amblyopic and control subjects. We did not observe any significant difference in terms of express saccades production between the control and amblyopic subjects. Our findings may suggest that amblyopia does not alter physiological mechanisms related to the efficiency of visual attention/fixation disengagement as supported by the observation that the gap effect and express saccades production was comparable between the normal and amblyopic subjects.
弱视是一种神经发育性视觉障碍，与儿童早期异常的视觉刺激有关。尽管我们对弱视患者空间视觉缺陷的认识已经很充分，但弱视患者眼球运动的神经控制仍有待探索。在本研究中，我们评估了间隙效应，并首次（据我们所知）在弱视（斜视性和屈光参差性）和年龄匹配的对照组受试者中研究了快速扫视的产生。我们比较了弱视组和对照组在不同间隙条件下（“无间隙”、50毫秒间隙和200毫秒间隙）的扫视潜伏期。我们的结果表明，在所有观察条件下，弱视组和对照组在间隙范式期间扫视潜伏期均缩短。此外，所有组和观察条件下（短间隙和长间隙持续时间）间隙效应的大小相当。此外，与先前结果一致，弱视眼与对照组非优势眼相比，扫视潜伏期增加。关于快速扫视的发生，与50毫秒间隙和“无间隙”条件相比，200毫秒间隙条件下弱视和对照受试者的快速扫视数量均增加。我们没有观察到对照组和弱视组在快速扫视产生方面有任何显著差异。我们的研究结果可能表明，弱视不会改变与视觉注意力/注视脱离效率相关的生理机制，这一观察结果支持了正常受试者和弱视受试者之间的间隙效应和快速扫视产生相当的观点。
