Top–down processes allow the selection and prioritization of information by limiting attentional capture by distractors, and these mechanisms depend on task demands such as working memory (WM) load. However, bottom–up processes give salient stimuli a stronger neuronal representation and provoke attentional capture. The aim of this study was to examine the effect of salient nociceptive stimuli on WM while manipulating task demands. Twenty-one healthy participants performed a change detection task during which they had to determine whether 2 successive visual arrays were different or the same. Task demands were modulated by manipulating the WM load (set size included 2 or 4 objects to recall) and by the correspondence between the 2 successive visual arrays (change vs no change). Innocuous stimuli (control) or nociceptive stimuli (distractors) were delivered during the delay period between the 2 visual arrays. Contralateral delay activity and laser-evoked potentials were recorded to examine neural markers of visual WM and nociceptive processes. Nociceptive stimuli decreased WM performance depending on task demands (all P < 0.05). Moreover, compared with control stimuli, nociceptive stimuli abolished the increase in contralateral delay activity amplitude for set size 4 vs set size 2 (P = 0.04). Consistent with these results, laser-evoked potential amplitude was not decreased when task demands were high (P = 0.5). These findings indicate that WM may shield cognition from nociceptive stimuli, but nociceptive stimuli disrupt WM and alter task performance when cognitive resources become insufficient to process all task-relevant information.

自上而下的过程通过限制干扰物的注意力捕获来允许信息的选择和优先排序，这些机制取决于任务需求，例如工作记忆 (WM) 负载。然而，自下而上的过程使显着刺激具有更强的神经元表征并引发注意力捕获。本研究的目的是在处理任务需求时检查显着伤害性刺激对 WM 的影响。21 名健康参与者执行了一项变化检测任务，在此期间他们必须确定 2 个连续的视觉阵列是否不同或相同。通过操纵 WM 负载（设置大小包括 2 或 4 个要召回的对象）和 2 个连续视觉阵列之间的对应关系（变化与无变化）来调节任务需求。在 2 个视觉阵列之间的延迟期间传递无害刺激（对照）或伤害性刺激（干扰物）。对侧延迟活动和记录激光诱发电位以检查视觉 WM 和伤害感受过程的神经标记。伤害性刺激会根据任务需求降低 WM 性能（所有P < 0.05）。此外，与控制刺激相比，伤害性刺激消除了设置大小 4 与设置大小 2 的对侧延迟活动幅度的增加（P = 0.04）。与这些结果一致，当任务要求高时，激光诱发电位幅度没有降低（P = 0.5）。这些发现表明，WM 可能会保护认知免受伤害性刺激，但当认知资源不足以处理所有与任务相关的信息时，伤害性刺激会破坏 WM 并改变任务表现。