Abstract:
Representations of task-relevant object attributes (attentional templates) control the adaptive selectivity of visual processing. Previous studies have demonstrated that templates involved in the guidance of attention during visual search are activated in a preparatory fashion prior to the arrival of visual search displays. The current study investigated whether such proactive mechanisms are also triggered in non-search tasks, where attentional templates do not mediate the guidance of attention towards targets amongst distractors but are still necessary for subsequent target recognition processes. Participants either searched for colour-defined targets among multiple distractors or performed two other non-search tasks where imperative stimuli appeared without competing distractors (a colour-based Go/NoGo task, and a shape discrimination task where target colour was constant and could thus be ignored). Preparatory activation of colour-selective templates was tracked by measuring N2pc components (markers of attention allocation) to task-irrelevant colour singleton probes flashed every 200 ms during the interval between target displays. As expected, N2pcs were triggered by target-coloured probes in the search task, indicating that a corresponding guidance template was triggered proactively. Critically, clear probe N2pcs were also observed in the Go/NoGo task, and even in the shape discrimination task in an attenuated fashion. These findings demonstrate that the preparatory activation of feature-selective attentional task settings is not uniquely associated with the guidance of visual search but is also present in other types of visual selection tasks where guidance is not required.
摘要:
与任务相关的对象属性(注意力模板)的表示控制了视觉处理的自适应选择性。先前的研究已经证明,在视觉搜索期间涉及注意力引导的模板在视觉搜索显示到达之前以预备方式被激活。当前的研究调查了这种主动机制是否也在非搜索任务中被触发,注意模板不会在干扰者之间调解对目标的注意力引导,但对于随后的目标识别过程仍然是必要的。参与者要么在多个干扰者中搜索颜色定义的目标,要么执行另外两个非搜索任务,其中命令性刺激出现而没有竞争性干扰者(基于颜色的Go/NoGo任务,和形状辨别任务,其中目标颜色是恒定的,因此可以忽略)。通过测量N2pc成分(注意力分配的标记)来跟踪颜色选择模板的准备激活,以在目标显示之间的间隔内每200毫秒闪烁一次与任务无关的彩色单例探针。不出所料,N2pcs由搜索任务中的目标彩色探针触发,指示相应的指导模板是主动触发的。严重的,在Go/NoGo任务中也观察到清晰的探头N2pcs,甚至在形状辨别任务中以衰减的方式进行。这些发现表明,特征选择性注意任务设置的预备激活与视觉搜索的指导并不唯一相关,但也存在于不需要指导的其他类型的视觉选择任务中。