Alsius Agnès, Navarra Jordi, Soto-Faraco Salvador
Departament de Psicologia Bàsica, Universitat de Barcelona, Pg. Vall d'Hebrón 171, Barcelona, 08035, Spain.
Exp Brain Res. 2007 Nov;183(3):399-404. doi: 10.1007/s00221-007-1110-1.
One of the classic examples of multisensory integration in humans occurs when speech sounds are combined with the sight of corresponding articulatory gestures. Despite the longstanding assumption that this kind of audiovisual binding operates in an attention-free mode, recent findings (Alsius et al. in Curr Biol, 15(9):839-843, 2005) suggest that audiovisual speech integration decreases when visual or auditory attentional resources are depleted. The present study addressed the generalization of this attention constraint by testing whether a similar decrease in multisensory integration is observed when attention demands are imposed on a sensory domain that is not involved in speech perception, such as touch. We measured the McGurk illusion in a dual task paradigm involving a difficult tactile task. The results showed that the percentage of visually influenced responses to audiovisual stimuli was reduced when attention was diverted to a tactile task. This finding is attributed to a modulatory effect on audiovisual integration of speech mediated by supramodal attention limitations. We suggest that the interactions between the attentional system and crossmodal binding mechanisms may be much more extensive and dynamic than it was advanced in previous studies.
人类多感官整合的经典例子之一，是语音与相应发音手势的视觉信息相结合时发生的情况。尽管长期以来人们一直认为这种视听结合以无注意力模式运行，但最近的研究结果（阿尔修斯等人，《当代生物学》，2005年，第15卷第9期：839 - 843页）表明，当视觉或听觉注意力资源耗尽时，视听语音整合会减少。本研究通过测试当对不参与语音感知的感觉领域（如触觉）施加注意力需求时，是否会观察到多感官整合有类似的减少，来探讨这种注意力限制的普遍性。我们在一个涉及困难触觉任务的双重任务范式中测量了麦格克错觉。结果表明，当注意力转移到触觉任务时，对视听刺激的视觉影响反应百分比会降低。这一发现归因于超模态注意力限制对语音视听整合的调节作用。我们认为，注意力系统与跨模态结合机制之间的相互作用可能比以往研究中所提出的更为广泛和动态。
