Liesefeld Heinrich René, Liesefeld Anna M, Pollmann Stefan, Müller Hermann J
Department Psychologie, Ludwig-Maximilians-Universität, Munich, Germany.
Graduate School of Systemic Neurosciences, Ludwig-Maximilians-Universität, Munich, Germany.
Curr Top Behav Neurosci. 2019;41:87-113. doi: 10.1007/7854_2018_75.
Objects that stand out from the environment tend to be of behavioral relevance, and the visual system is tuned to preferably process these salient objects by allocating focused attention. However, attention is not just passively (bottom-up) driven by stimulus features, but previous experiences and task goals exert strong biases toward attending or actively ignoring salient objects. The core and eponymous assumption of the dimension-weighting account (DWA) is that these top-down biases are not as flexible as one would like them to be; rather, they are subject to dimensional constraints. In particular, DWA assumes that people can often not search for objects that have a particular feature but only for objects that stand out from the environment (i.e., that are salient) in a particular feature dimension. We review behavioral and neuroimaging evidence for such dimensional constraints in three areas: search history, voluntary target enhancement, and distractor handling. The first two have been the focus of research on DWA since its inception and the latter the subject of our more recent research. Additionally, we discuss various challenges to the DWA and its relation to other prominent theories on top-down influences in visual search.
在环境中突出的物体往往具有行为相关性，视觉系统会通过分配集中注意力来优先处理这些显著物体。然而，注意力并非仅仅由刺激特征被动地（自下而上地）驱动，先前的经验和任务目标会对关注或主动忽略显著物体产生强烈的偏向。维度加权理论（DWA）的核心及同名假设是，这些自上而下的偏向并不像人们期望的那样灵活；相反，它们受到维度限制。具体而言，DWA假设人们通常无法搜索具有特定特征的物体，而只能搜索在特定特征维度上从环境中突出（即显著）的物体。我们回顾了在三个领域中关于这种维度限制的行为和神经影像学证据：搜索历史、自愿目标增强和干扰物处理。前两个领域自DWA提出以来一直是研究重点，而后者是我们近期研究的主题。此外，我们讨论了DWA面临的各种挑战及其与视觉搜索中自上而下影响的其他重要理论的关系。
