Uncovering mechanisms of attentional control by tracking preparatory states in real time

我们对外部世界的感知，以及我们与外部物体和事件互动的方式，不仅由传入的感官信息决定，也由我们的预期和意图决定。我们不仅仅是知觉信号的被动接受者--很多时候，我们已经为期待什么和在特定情况下什么将是相关的做好了准备。做好准备可以让我们更有效地应对环境，把注意力集中在重要的事情上，过滤掉其他可以安全地忽略的信息。显然，准备是人类认知最重要的方面之一--它塑造了我们的意识体验，并指导我们与世界的互动。然而，我们仍然对如何为即将到来的任务做准备知之甚少。这样做的原因是，准备状态的激活是一种内部心理现象，通常发生在没有任何直接可观察到的行为的情况下。因此，这种状态很难用实验心理学中传统的基于成绩的方法来评估。在这个项目中，我们将通过记录观察者为即将到来的视觉搜索任务做准备时的大脑活动(EEG)来直接测量准备状态。在这些任务中，他们必须在多个不相关的对象(干扰物)中搜索特定的已知目标对象。他们可以通过激活这个目标对象的心理表征来准备搜索，然后当目标出现时，这将有助于引导他们的注意力到目标上。我们最近开发了一种新的方法，可以在激活时直接测量这种准备状态，并实时跟踪这些激活状态。因此，我们现在可以直接观察准备工作何时开始，以及准备工作如何随时间变化。我们还可以确定这种预备状态的内容。例如，当我们准备在杂乱的办公桌上搜索手机时，我们是激活了整个物体的脑海中的图像，还是只激活了这个物体的特定属性，比如它的颜色或形状？我们是否可以控制我们准备的内容，并在不同的情况下故意使用不同的准备策略？例如，我们是否更有效地为与激励相关的任务目标做准备，因为它们与更高的奖励相关？当任务目标突然改变时，我们能以多快的速度改变受影响的准备状态？重要的是，我们还将调查选择性注意准备和失败之间的联系。我们经常找不到我们正在寻找的东西，或者注意力会被不相关的物体和事件分散。通过比较在随后的注意力选择有效运作的情况下和在注意力选择无效的情况下测量的准备状态，我们可以发现准备状态的波动如何产生不同的行为结果。我们如何为当前相关的对象和事件做准备的问题对于选择性注意的心理学理论来说是重要的，因此我们的研究将对注意研究具有重要的理论和概念意义。虽然这个项目的重点是基础研究问题，但从长远来看，这项研究的见解也将与更多的应用问题相关。在现代技术发达的社会中，生活的一个关键特征是多种信息源之间无处不在的竞争，这导致了对注意对象选择和选择的永久需求。对准备状态的性质以及这些状态如何决定我们关注什么以及何时关注的新见解，对父母养育、教育、工作场所设计和经济决策等不同领域具有明显的实际影响，也可能为研究注意力控制缺陷，如ADHD提供新的方法。

Our perception of the outside world, and the way that we interact with external objects and events, is not just determined by incoming sensory information, but also by our expectations and intentions. We are not merely passive recipients of perceptual signals - very often, we are already prepared for what to expect and for what will be relevant in a given situation. Being prepared allows us to deal with our environment more effectively, by focussing our attention on what is important, and filtering out other information that can be safely ignored. It is obvious that preparation is one of the most important aspects of human cognition - it shapes our conscious experience and guides our interactions with the world. However, we still know very little about how we prepare for upcoming tasks. The reason for this is that the activation of preparatory states is an internal mental phenomenon that usually takes place in the absence of any directly observable behaviour. Such states are therefore difficult to assess with the conventional performance-based measures of experimental psychology. In this project, we will measure preparatory states directly, while they occur, by recording brain activity (EEG) from observers when they prepare for upcoming visual search tasks. In these tasks, they have to search for a specific known target object among multiple irrelevant objects (distractors). They can prepare for search by activating a mental representation of this target object, which will then help to guide their attention to the target when it appears. We have recently developed new methods to measure such preparatory "images in the mind" directly, at the moment when they are activated, and to track these activation states in real time. We can therefore now directly observe when preparation starts and how it changes across time. We can also determine the content of such preparatory states. For example, when we prepare to search for our mobile phone on our cluttered desk, do we activate a mental image of the whole object, or just a specific attribute of this object, such as its colour or shape? Can we control the content of what we prepare for, and deliberately employ different preparation strategies in different contexts? For example, do we prepare more effectively for task goals that are motivationally relevant, because they are associated with a higher reward? How quickly can we change preparatory states affected when task goals suddenly change? Importantly, we will also investigate links between preparation and failures of selective attention. We often fail to find what we are looking for, or attention can be distracted by irrelevant objects and events. By comparing preparatory states measured on an occasion where subsequent attentional selection operates efficiently and on an occasion where it does not, we can find out how fluctuations in preparedness produce different behavioural outcomes. The question how we prepare for currently relevant objects and events is important for psychological theories of selective attention, and our research will therefore have important theoretical and conceptual implications for attention research. Although this project focuses on basic research questions, it is likely that in the longer term, the insights from this research will also become relevant for more applied questions. A key feature of life in modern technologically advanced societies is the ubiquitous competition between multiple sources of information, which result in permanent demands on attentional object selection and choice. New insights into the nature of preparatory states and how these states determine what we attend to and when has clear practical implications for areas as diverse as parenting, education, workplace design, and economic decision making, and may also offer new ways of investigating deficits of attentional control, such as ADHD.