Zhang Yuan, Agosti Giulia, Guan Shuchen, Braun Doris I, Gegenfurtner Karl R
J Opt Soc Am A Opt Image Sci Vis. 2025 May 1;42(5):B256-B265. doi: 10.1364/JOSAA.545021.
We investigated the interplay between luminance and heterochromatic brightness in guiding oculomotor behavior, particularly in saccades and smooth pursuit eye movements. We were particularly interested in testing whether mechanisms for eye target selection incorporate contributions from S-cones. Luminance, typically measured using the CIE's luminous efficiency function (), has limitations in representing the perceived brightness of heterochromatic stimuli, especially with bluish and yellowish lights. S-cones do not contribute significantly to luminance but do influence brightness perception. To examine the S-cone contributions to oculomotor behavior, we measured the target choices of saccades and smooth pursuit between equi-luminant bluish and yellowish stimuli, with paradigms producing a wide range of latencies. Our results show that at shorter latencies, luminance primarily drives both eye movements, with equi-luminant bluish and yellowish stimuli being chosen equally often. However, as latency increases, participants tend to choose bluish stimuli more frequently, suggesting that heterochromatic brightness plays a major role in longer-latency eye movements. This indicates that S-cone input may influence target selection as latency increases, highlighting a dynamic interaction between luminance and brightness in oculomotor decisions. We were particularly interested in investigating whether the mechanism responsible for eye movement target selection incorporates S-cone activity.
我们研究了亮度与异色亮度在引导眼球运动行为(特别是扫视和平滑追踪眼球运动)中的相互作用。我们特别感兴趣的是测试眼球目标选择机制是否纳入了S-视锥细胞的贡献。亮度通常使用国际照明委员会(CIE)的发光效率函数来测量,在表示异色刺激的感知亮度方面存在局限性,尤其是对于蓝光和黄光。S-视锥细胞对亮度的贡献不大,但确实会影响亮度感知。为了研究S-视锥细胞对眼球运动行为的贡献,我们测量了在等亮度的蓝光和黄光刺激之间扫视和平滑追踪的目标选择,采用了产生广泛潜伏期的范式。我们的结果表明,在较短的潜伏期内,亮度主要驱动两种眼球运动,等亮度的蓝光和黄光刺激被选择的频率相同。然而,随着潜伏期的增加,参与者倾向于更频繁地选择蓝光刺激,这表明异色亮度在较长潜伏期的眼球运动中起主要作用。这表明随着潜伏期的增加,S-视锥细胞输入可能会影响目标选择,突出了亮度和亮度在眼球运动决策中的动态相互作用。我们特别感兴趣的是研究负责眼球运动目标选择的机制是否包含S-视锥细胞活动。