Siegle Greg J, Steinhauer Stuart R, Stenger V Andrew, Konecky Roma, Carter Cameron S
University of Pittsburgh, Pittsburgh, PA, USA. gsiegle+@pitt.edu
Neuroimage. 2003 Sep;20(1):114-24. doi: 10.1016/s1053-8119(03)00298-2.
Potential contributions of concurrently acquired pupil dilation data to functional magnetic resonance imaging (fMRI) experiments were examined. Sixteen healthy participants completed a working memory task (digit sorting) during measurement of pupil dilation outside the fMRI environment and during concurrent 3T fMRI assessment. Pupil dilation increased parametrically with task difficulty inside and outside the scanner, on a similar time course, suggesting that task demand was similar in both environments. The time course of pupil dilation during digit sorting was similar to the time course of the fMRI signal in the middle frontal gyrus, suggesting that middle-frontal gyrus activity indexed the engagement working memory processes. Incorporating individual differences in pupil dilation improved the sensitivity and specificity of general linear modeling analyses of activity in the middle frontal gyrus, above and beyond standard analytic techniques. Results suggest concurrent pupil dilation during fMRI assessment can help to (1) specify whether task demand is the same inside and outside the fMRI environment, (2) resolve the extent to which fMRI signals reflect different aspects of event-related designs, and (3) explain variation in fMRI data due to individual differences in information processing.
研究了同时获取的瞳孔扩张数据对功能磁共振成像（fMRI）实验的潜在贡献。16名健康参与者在fMRI环境外测量瞳孔扩张期间以及同时进行3T fMRI评估期间完成了一项工作记忆任务（数字分类）。在扫描仪内外，瞳孔扩张随任务难度呈参数性增加，时间进程相似，这表明两种环境下的任务需求相似。数字分类期间瞳孔扩张的时间进程与额中回fMRI信号的时间进程相似，这表明额中回活动反映了工作记忆过程的参与情况。纳入瞳孔扩张的个体差异提高了额中回活动的一般线性模型分析的敏感性和特异性，超过了标准分析技术。结果表明，fMRI评估期间同时进行瞳孔扩张有助于：（1）确定fMRI环境内外的任务需求是否相同；（2）确定fMRI信号反映事件相关设计不同方面的程度；（3）解释由于信息处理个体差异导致的fMRI数据变化。
