Behavioural and electrophysiological investigations of individual differences in dual-task attention costs

在我们的日常生活中，我们经常同时执行两项任务，或者试图同时处理不止一件事情(例如，开车时打手机)。我们想同时处理多项任务的愿望往往与这样一个事实相冲突，即我们在任何给定时间所能处理的信息量都是有限的。当我们同时执行两项要求注意力的任务时，其中一项或两项任务的表现往往会受到影响。为了研究多任务处理的困难，在我的实验室里，像字母这样的视觉刺激被快速连续地呈现在计算机屏幕上的同一位置。两个目标作为信息流的一部分出现，这两个目标之间的时间间隔从不到十分之一秒到近两秒不等。参与者被要求报告这两个目标。测量了对目标1和目标2的行为反应的准确性。对目标2的反应显示，当目标在时间上被紧密地呈现在一起时，准确度显著下降--这种现象被称为注意眨眼(AB)。最近的研究表明，AB的大小因个体而异，但对于同一个人来说，随着时间的推移相对稳定。我的实验室最近的研究表明，AB大小的个体差异可以通过各种性格、脑波和认知表现指标来预测。我认为，AB大小的个体差异是由于注意焦点和投资的个体差异，而前扣带皮质驱动的操作监控调节了这一差异。这项拟议研究的目标是记录大脑和行为测量，并在一系列研究项目中使用个体差异方法来测试这种概念化。这种理解AB的创新的个体差异方法，结合生理测量的使用，将帮助我们理解为什么一些人比其他人更有能力克服双重任务的注意力成本。这不仅将提供对AB的潜在性质的洞察，而且可能帮助我们深入了解人类的注意处理调制，这可能是使用其他方法难以实现的。这些知识可能会帮助我们制定成功的战略，在日常生活中降低这些成本。

In our daily lives we often perform two tasks at once, or try to attend to more than one thing at a time (for example, talking on a cell phone while driving). Our desire to multi-task often conflicts with the fact that there are limits on how much information we can attend to at any given time. When we perform two attention-demanding tasks at the same time, performance on one or both tasks often suffers. To investigate multi-tasking difficulties, in my lab visual stimuli such as letters are presented in rapid succession in the same location on the computer screen. Two targets are presented as part of the stream of information, and the time interval between these two targets varies from less than one-tenth of a second to almost two seconds. Participants are asked to report both of the targets. Behavioural response accuracy to target 1 and target 2 are measured. Responses to target 2 show a marked decreased in accuracy when targets are presented closely together in time - a phenomenon known as the attentional blink (AB). Recent research has shown that the size of the AB differs across individuals, but is relatively stable across time for the same individual. Recent work from my lab has shown that individual differences in the size of the AB are predicted by various dispositional, brain-wave, and cognitive performance measures. I suggest that individual differences in AB size result from individual differences in attentional focus and investment, as modulated by anterior cingulate cortex driven performance monitoring. The goal of the proposed research is to record both brain and behavioural measures and to use an individual differences approach to test this conceptualization in a series of research projects. This innovative individual differences approach to understanding AB, combined with the use of physiological measures, will help us understand why some individuals are better able to overcome dual-task attention costs than others. This will not only provide insight into the underlying nature of the AB, but may help us arrive at insights into human attentional processing modulations that may be difficult to achieve using other approaches. This knowledge may help us to lead to successful strategies for reducing these costs in our daily life.