Sandhu Rajwant, Dyson Benjamin James
Department of Psychology, Ryerson University, 350 Victoria Street, Toronto, ON, M5B 2K3, Canada.
University of Sussex, Brighton, UK.
Exp Brain Res. 2016 May;234(5):1279-91. doi: 10.1007/s00221-015-4517-0. Epub 2015 Dec 15.
Visual distractor processing tends to be more pronounced when the perceptual load (PL) of a task is low compared to when it is high [perpetual load theory (PLT); Lavie in J Exp Psychol Hum Percept Perform 21(3):451-468, 1995]. While PLT is well established in the visual domain, application to cross-modal processing has produced mixed results, and the current study was designed in an attempt to improve previous methodologies. First, we assessed PLT using response competition, a typical metric from the uni-modal domain. Second, we looked at the impact of auditory load on visual distractors, and of visual load on auditory distractors, within the same individual. Third, we compared individual uni- and cross-modal selective attention abilities, by correlating performance with the visual Attentional Network Test (ANT). Fourth, we obtained a measure of the relative processing efficiency between vision and audition, to investigate whether processing ease influences the extent of distractor processing. Although distractor processing was evident during both attend auditory and attend visual conditions, we found that PL did not modulate processing of either visual or auditory distractors. We also found support for a correlation between the uni-modal (visual) ANT and our cross-modal task but only when the distractors were visual. Finally, although auditory processing was more impacted by visual distractors, our measure of processing efficiency only accounted for this asymmetry in the auditory high-load condition. The results are discussed with respect to the continued debate regarding the shared or separate nature of processing resources across modalities.
与高感知负荷时相比，当一项任务的感知负荷（PL）较低时，视觉干扰项处理往往更为明显[感知负荷理论（PLT）；拉维，《实验心理学杂志：人类感知与表现》21(3):451 - 468，1995年]。虽然PLT在视觉领域已得到充分确立，但应用于跨模态处理时产生了混合结果，本研究旨在改进先前的方法。首先，我们使用反应竞争来评估PLT，这是单模态领域的一种典型指标。其次，我们考察了在同一个体内听觉负荷对视觉干扰项的影响，以及视觉负荷对听觉干扰项的影响。第三，我们通过将表现与视觉注意网络测试（ANT）相关联，比较了个体的单模态和跨模态选择性注意能力。第四，我们获得了视觉与听觉之间相对处理效率的度量，以研究处理的难易程度是否会影响干扰项处理的程度。尽管在专注听觉和专注视觉条件下干扰项处理都很明显，但我们发现PL并未调节视觉或听觉干扰项的处理。我们还发现单模态（视觉）ANT与我们的跨模态任务之间存在相关性，但仅当干扰项为视觉时。最后，尽管听觉处理受视觉干扰项的影响更大，但我们的处理效率度量仅在听觉高负荷条件下解释了这种不对称性。我们将结合关于跨模态处理资源共享或分离性质的持续争论来讨论这些结果。
