Wojciulik E, Kanwisher N, Driver J
Department of Psychology, University of California, Los Angeles, California 90095, USA.
J Neurophysiol. 1998 Mar;79(3):1574-8. doi: 10.1152/jn.1998.79.3.1574.
Several lines of evidence demonstrate that faces undergo specialized processing within the primate visual system. It has been claimed that dedicated modules for such biologically significant stimuli operate in a mandatory fashion whenever their triggering input is presented. However, the possible role of covert attention to the activating stimulus has never been examined for such cases. We used functional magnetic resonance imaging to test whether face-specific activity in the human fusiform face area (FFA) is modulated by covert attention. The FFA was first identified individually in each subject as the ventral occipitotemporal region that responded more strongly to visually presented faces than to other visual objects under passive central viewing. This then served as the region of interest within which attentional modulation was tested independently, using active tasks and a very different stimulus set. Subjects viewed brief displays each comprising two peripheral faces and two peripheral houses (all presented simultaneously). They performed a matching task on either the two faces or the two houses, while maintaining central fixation to equate retinal stimulation across tasks. Signal intensity was reliably stronger during face-matching than house matching in both right- and left-hemisphere predefined FFAs. These results show that face-specific fusiform activity is reduced when stimuli appear outside (vs. inside) the focus of attention. Despite the modular nature of the FFA (i.e., its functional specificity and anatomic localization), face processing in this region nonetheless depends on voluntary attention.
多条证据表明，面孔在灵长类动物视觉系统中会经历专门的处理过程。有人声称，针对此类具有生物学意义的刺激的专用模块，在其触发输入出现时会以强制方式运行。然而，对于此类情况，从未研究过对激活刺激的隐蔽注意可能发挥的作用。我们使用功能磁共振成像来测试人类梭状面孔区（FFA）中对面孔的特异性活动是否会受到隐蔽注意的调节。首先在每个受试者个体中确定FFA，将其作为枕颞腹侧区域，在被动中央注视下，该区域对视觉呈现的面孔的反应比对其他视觉对象的反应更强烈。然后，这一区域作为感兴趣区域，在其中使用主动任务和非常不同的刺激集独立测试注意调节。受试者观看简短的展示，每次展示包括两个外周面孔和两个外周房屋（所有同时呈现）。他们对两张面孔或两所房屋执行匹配任务，同时保持中央注视，以使各任务的视网膜刺激相等。在左右半球预先定义的FFA中，面孔匹配期间的信号强度比房屋匹配期间可靠地更强。这些结果表明，当刺激出现在注意焦点之外（相对于之内）时，梭状面孔区对面孔的特异性活动会降低。尽管FFA具有模块化性质（即其功能特异性和解剖定位），但该区域的面孔处理仍依赖于自愿注意。
