Data from: The effect of Speed of Processing training on microsaccade magnitude

Older adults experience cognitive deficits that can lead to driving errors and a loss of mobility. Fortunately, some of these deficits can be ameliorated with targeted interventions which improve the speed and accuracy of simultaneous attention to a central and a peripheral stimulus called Speed of Processing training. To date, the mechanisms behind this effective training are unknown. We hypothesized that one potential mechanism underlying this training is a change in distribution of eye movements of different amplitudes. Microsaccades are small amplitude eye movements made when fixating on a stimulus, and are thought to counteract the "visual fading" that occurs when static stimuli are presented. Due to retinal anatomy, larger microsaccadic eye movements are needed to move a peripheral stimulus between receptive fields and counteract visual fading. Alternatively, larger microsaccades may decrease performance due to neural suppression. Because larger microsaccades could aid or hinder peripheral vision, we examine the distribution of microsaccades during stimulus presentation. Our results indicate that there is no statistically significant change in the proportion of large amplitude microsaccades during a Useful Field of View-like task after training in a small sample of older adults. Speed of Processing training does not appear to result in changes in microsaccade amplitude, suggesting that the mechanism underlying Speed of Processing training is unlikely to rely on microsaccades.

老年群体存在认知缺损，此类缺损可引发驾驶失误并造成行动能力丧失。所幸，部分此类认知缺损可通过针对性干预手段得到改善——这类干预可提升个体同时关注中央与周边刺激的速度与准确性，该训练方法被称为加工速度训练（Speed of Processing training）。截至目前，该高效训练的背后机制仍未阐明。我们推测，该训练的潜在作用机制之一，是不同幅度的眼球运动分布发生了改变。微扫视（Microsaccades）指个体在注视刺激物时产生的小幅眼球运动，被认为可抵消静态刺激呈现时出现的“视觉消退”现象。受视网膜解剖结构的限制，若要让周边刺激在不同感受野之间移动并抵消视觉消退，需要幅度更大的微扫视眼动。另一方面，由于神经抑制效应，幅度更大的微扫视也可能降低任务表现。鉴于幅度更大的微扫视既可能辅助也可能妨碍周边视觉功能，我们对刺激呈现过程中的微扫视分布展开了研究。本研究结果显示，在小样本老年群体中，经过加工速度训练后，类有效视野（Useful Field of View）任务期间，大幅值微扫视的占比未出现具有统计学意义的显著变化。加工速度训练似乎并未引起微扫视幅度的改变，这表明该训练的潜在作用机制不太可能依赖微扫视活动。