Abstract:
Sensory inputs enter a constantly active brain, whose state is always changing from one moment to the next. Currently, little is known about how ongoing, spontaneous brain activity participates in online task processing. We employed 7 Tesla fMRI and a threshold-level visual perception task to probe the effects of prestimulus ongoing brain activity on perceptual decision-making and conscious recognition. Prestimulus activity originating from distributed brain regions, including visual cortices and regions of the default-mode and cingulo-opercular networks, exerted a diverse set of effects on the sensitivity and criterion of conscious recognition, and categorization performance. We further elucidate the mechanisms underlying these behavioral effects, revealing how prestimulus activity modulates multiple aspects of stimulus processing in highly specific and network-dependent manners. These findings reveal heretofore unknown network mechanisms underlying ongoing brain activity\'s influence on conscious perception, and may hold implications for understanding the precise roles of spontaneous activity in other brain functions.
摘要:
感官输入进入一个不断活跃的大脑,他们的状态总是从一个时刻变化到下一个时刻。目前,很少有人知道如何进行,自发的大脑活动参与在线任务处理。我们采用了7TeslafMRI和阈值水平的视觉感知任务来探测前刺激持续的大脑活动对感知决策和意识识别的影响。来自分布的大脑区域的前刺激活动,包括默认模式和扣带操作网络的视觉皮层和区域,对意识识别的敏感性和标准产生了一系列不同的影响,和分类性能。我们进一步阐明了这些行为效应的潜在机制,揭示了前刺激活动如何以高度特定和网络相关的方式调节刺激处理的多个方面。这些发现揭示了迄今为止未知的网络机制,潜在的大脑活动对意识感知的影响,并且可能对理解自发活动在其他大脑功能中的确切作用有意义。