School of Psychology, Vita-Salute San Raffaele University, Via Olgettina 58, 20132, Milan, Italy.
Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy.
Psychon Bull Rev. 2020 Aug;27(4):724-734. doi: 10.3758/s13423-020-01752-5.
The current study investigates the role of temporal processing in the visual domain in participants with developmental dyslexia (DD), the most common neurodevelopmental disorder, which is characterized by severe and specific difficulties in learning to read despite normal intelligence and adequate education. Specifically, our aim was to test whether DD is associated with a general impairment of temporal sensory processing or a specific deficit in temporal integration (which ensures stability of object identity and location) or segregation (which ensures sensitivity to changes in visual input). Participants with DD performed a task that measured both temporal integration and segregation using an identical sequence of two displays separated by a varying interstimulus interval (ISI) under two different task instructions. Results showed that participants with DD performed worse in the segregation task, with a shallower slope of the psychometric curve of percentage correct as a function of the ISI between the two target displays. Moreover, we found also a relationship between temporal segregation performance and text, words, and pseudowords reading speeds at the individual level. In contrast, no significant association between reading (dis)ability and temporal integration emerged. The current findings provide evidence for a difference in the fine temporal resolution of visual processing in DD and, considering the growing evidence about a link between visual temporal segregation and neural oscillations at specific frequencies, they support the idea that DD is characterized by an altered oscillatory sampling within the visual system.
本研究调查了发展性阅读障碍（DD）患者视觉领域中时间处理的作用。DD 是最常见的神经发育障碍，其特征是尽管智力正常且接受了足够的教育，但在学习阅读方面仍存在严重和特定的困难。具体而言，我们的目的是测试 DD 是否与时间感觉处理的一般损伤有关，或者与时间整合（确保对象身份和位置的稳定性）或分离（确保对视觉输入变化的敏感性）的特定缺陷有关。DD 患者在两种不同的任务指令下，使用两个显示之间的变化刺激间间隔（ISI）相同的序列，完成了一项同时测量时间整合和分离的任务。结果表明，DD 患者在分离任务中的表现较差，两个目标显示之间的 ISI 与正确百分比的心理测量曲线斜率较浅。此外，我们还在个体水平上发现了时间分离性能与文本、单词和伪单词阅读速度之间的关系。相比之下，阅读（障碍）能力与时间整合之间没有显著的关联。当前的研究结果为 DD 患者在视觉处理的精细时间分辨率方面存在差异提供了证据，并且考虑到视觉时间分离与特定频率的神经振荡之间存在联系的证据越来越多，这些结果支持了这样一种观点，即 DD 的特征是视觉系统中振荡采样的改变。
