Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada.
Hum Mov Sci. 2013 Apr;32(2):328-42. doi: 10.1016/j.humov.2012.11.001. Epub 2013 Apr 29.
Recent findings suggest that rapid perturbation-evoked reach-to-grasp balance-recovery reactions can be (and often are) guided by visuospatial information stored in working memory. To further our understanding, the present study examined the influence of memory-decay and concurrent cognitive-task performance on the speed, accuracy and effectiveness of these reactions by using liquid-crystal goggles to initiate occlusion of vision at various "recall-delay" times prior to perturbation-onset, in ten healthy young-adults. A small handhold was moved unpredictably to one of four locations 2s prior to vision-occlusion; reactions to recover balance by grasping the handhold were evoked by unpredictable antero-posterior platform-translation perturbations. Recall-delay time (0s/2s/5s/10s) was randomized, and subjects performed a spatial- or non-spatial-memory task during the delay-time in a subset of trials. Consistent with studies of volitional reach-to-grasp, recall-delay led to some reduction in endpoint accuracy; however, unlike those studies, the present results showed no evidence that recall-delay led to slowing of the arm movement. Both spatial and non-spatial cognitive tasks had similar effects (slowing of movement initiation and execution), suggesting these effects were related to generic attentional demands rather than competition for specific resources related to spatial working memory. Further work is needed to determine effects of age-related impairments in visuospatial memory and attentional capacity.
最近的研究结果表明，快速的扰动诱发的伸手抓握平衡恢复反应可以（并且经常是）由工作记忆中存储的视空间信息指导。为了进一步了解这一情况，本研究通过在扰动发生前使用液晶护目镜在不同的“回忆延迟”时间内开始遮挡视觉，检查了记忆衰减和并发认知任务表现对这些反应的速度、准确性和有效性的影响，在 10 名健康的年轻成年人中进行了实验。在视觉遮挡前 2 秒，一个小手柄会不可预测地移动到四个位置之一；通过不可预测的前后平台平移扰动来诱发抓握手柄以恢复平衡的反应。回忆延迟时间（0s/2s/5s/10s）是随机的，并且在部分试验中，受试者在延迟时间内执行空间或非空间记忆任务。与自愿伸手抓握的研究一致，回忆延迟导致末端精度有所降低；然而，与那些研究不同，本研究结果没有证据表明回忆延迟会导致手臂运动的减慢。空间和非空间认知任务都有类似的效果（运动起始和执行的减慢），这表明这些效果与一般的注意力需求有关，而不是与空间工作记忆相关的特定资源竞争有关。需要进一步的工作来确定与年龄相关的视空间记忆和注意力能力损伤的影响。
