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 p...

老年群体常出现认知功能缺损，这可能引发驾驶失误乃至行动能力丧失。所幸，部分此类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外周刺激的速度与精度，即加工速度训练（Speed of Processing training）。迄今为止，该高效训练的作用机制仍未明确。我们提出假说，认为该训练的潜在作用机制之一，是不同幅度眼球运动的分布发生改变。微扫视（Microsaccades）是个体注视刺激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。由于视网膜的解剖结构特性，要让外周刺激在感受野之间移动并抵消视觉消退，需要产生幅度更大的微扫视。反之，由于神经抑制效应，幅度更大的微扫视可能会降低任务表现。由于幅度更大的微扫视既可能助力也可能阻碍……