University of Alberta, Canada.
J Cogn Neurosci. 2012 May;24(5):1233-52. doi: 10.1162/jocn_a_00206. Epub 2012 Feb 14.
Traditionally, emotional stimuli have been thought to be automatically processed via a bottom-up automatic "capture of attention" mechanism. Recently, this view has been challenged by evidence that emotion processing depends on the availability of attentional resources. Although these two views are not mutually exclusive, direct evidence reconciling them is lacking. One limitation of previous investigations supporting the traditional or competing views is that they have not systematically investigated the impact of emotional charge of task-irrelevant distraction in conjunction with manipulations of attentional demands. Using event-related fMRI, we investigated the nature of emotion-cognition interactions in a perceptual discrimination task with emotional distraction by manipulating both the emotional charge of the distracting information and the demands of the main task. Our findings show that emotion processing is both automatic and modulated by attention, but emotion and attention were only found to interact when finer assessments of emotional charge (comparison of most vs. least emotional conditions) were considered along with an effective manipulation of processing load (high vs. low). The study also identified brain regions reflecting the detrimental impact of emotional distraction on performance as well as regions involved in coping with such distraction. Activity in the dorsomedial pFC and ventrolateral pFC was linked to a detrimental impact of emotional distraction, whereas the dorsal ACC and lateral occipital cortex were involved in helping with emotional distraction. These findings demonstrate that task-irrelevant emotion processing is subjective to both the emotional content of distraction and the level of attentional demand.
传统上,情绪刺激被认为是通过自下而上的自动“注意力捕获”机制自动处理的。最近,有证据表明情绪处理取决于注意力资源的可用性,这一观点对上述观点提出了挑战。尽管这两种观点并不相互排斥,但缺乏直接证据来调和它们。支持传统或竞争观点的先前研究的一个局限性是,它们没有系统地调查与注意力需求操作相结合的无关分心任务的情绪负荷对情绪处理的影响。我们使用事件相关 fMRI 研究了在带有情绪分心的知觉辨别任务中情绪与认知相互作用的性质,通过同时操纵分心信息的情绪负荷和主要任务的注意力需求来实现。我们的研究结果表明,情绪处理是自动的,并且受到注意力的调节,但只有在更精细地评估情绪负荷(比较最情绪化和最不情绪化的条件)以及有效操纵处理负载(高负载和低负载)时,才会发现情绪和注意力相互作用。该研究还确定了反映情绪分心对表现的不利影响的大脑区域,以及涉及应对这种分心的大脑区域。背内侧前额叶皮层和腹外侧前额叶皮层的活动与情绪分心的不利影响有关,而背侧前扣带皮层和外侧枕叶皮层则参与了应对情绪分心。这些发现表明,无关的情绪处理既受到分心的情绪内容的影响,也受到注意力需求水平的影响。