Medical Research Council Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, UK.
Medical Research Council Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, UK.
Cortex. 2018 Oct;107:166-179. doi: 10.1016/j.cortex.2017.09.004. Epub 2017 Sep 13.
The finding of increased fronto-parietal activity during conscious and attended perception forms a key basis for theories of consciousness and attention. However, this finding comes largely from studies that required explicit detection of events in a way that made detection the goal of the ongoing task. This is an important confound because goal completion itself elicits fronto-parietal activity. In everyday life attended and conscious perception is instrumental in achieving our goals but rarely a goal in itself. Here we examined whether conscious perception that was instrumental to participants' current goals, but not a goal in itself, elicited increased fronto-parietal activity. In Experiments 1 and 2 participants attended to a stream of letters (1 per second) to detect occasional targets in their midst. We found that consciousness of, and attention to, these highly visible non-targets events deactivated fronto-parietal regions. In Experiment 3 participants heard a loud auditory cue that had to be retained in memory for up to 9 sec before being used to select the correct rule for completing the goal. No increased fronto-parietal activity was observed even for such salient, attended and remembered event. In contrast, robust fronto-parietal activation was observed across all the experiments for goal completion events. The results indicate that increased fronto-parietal activity is not a necessary correlate of conscious and attended perception. We speculate that fronto-parietal deactivation during non-target events may be related to the suppression of potential interference from salient, conscious, but non-goal stimuli.
在有意识和关注的情况下，额顶区域活动增加的发现为意识和注意理论提供了重要基础。然而，这一发现主要来自于那些要求以明确检测事件的方式进行的研究，而这种检测方式使检测成为正在进行的任务的目标。这是一个重要的混杂因素，因为目标的完成本身就会引起额顶区域的活动。在日常生活中，关注和有意识的感知对于实现我们的目标是至关重要的，但很少是目标本身。在这里，我们研究了一种情况，即对于参与者当前目标有帮助但本身不是目标的有意识感知是否会引起额顶区域活动的增加。在实验 1 和实验 2 中，参与者关注一连串的字母（每秒一个），以检测其中偶尔出现的目标。我们发现，对这些高度可见的非目标事件的意识和关注会使额顶区域失活。在实验 3 中，参与者听到一个响亮的听觉提示，该提示必须在 9 秒内保存在记忆中，然后才能用于选择完成目标的正确规则。即使是如此突出、受关注和被记住的事件，也没有观察到额顶区域活动的增加。相比之下，在所有实验中，目标完成事件都观察到了强烈的额顶区域激活。结果表明，额顶区域活动的增加不是有意识和关注感知的必要相关物。我们推测，在非目标事件期间额顶区域的失活可能与对突出的、有意识但非目标刺激的潜在干扰的抑制有关。
