Brouwer Gijs Joost, Tong Frank, Hagoort Peter, van Ee Raymond
Department of Physics, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands.
PLoS One. 2009;4(3):e5056. doi: 10.1371/journal.pone.0005056. Epub 2009 Mar 31.
We employed a parametric psychophysical design in combination with functional imaging to examine the influence of metric changes in perceptual incongruence on perceptual alternation rates and cortical responses. Subjects viewed a bistable stimulus defined by incongruent depth cues; bistability resulted from incongruence between binocular disparity and monocular perspective cues that specify different slants (slant rivalry). Psychophysical results revealed that perceptual alternation rates were positively correlated with the degree of perceived incongruence. Functional imaging revealed systematic increases in activity that paralleled the psychophysical results within anterior intraparietal sulcus, prior to the onset of perceptual alternations. We suggest that this cortical activity predicts the frequency of subsequent alternations, implying a putative causal role for these areas in initiating bistable perception. In contrast, areas implicated in form and depth processing (LOC and V3A) were sensitive to the degree of slant, but failed to show increases in activity when these cues were in conflict.
我们采用参数化心理物理学设计并结合功能成像，以研究感知不一致中的度量变化对感知交替率和皮层反应的影响。受试者观看由不一致的深度线索定义的双稳态刺激；双稳态是由指定不同倾斜度的双眼视差和单眼透视线索之间的不一致导致的（倾斜竞争）。心理物理学结果表明，感知交替率与感知到的不一致程度呈正相关。功能成像显示，在感知交替开始之前，顶内沟前部的活动系统增加，这与心理物理学结果平行。我们认为，这种皮层活动预测了随后交替的频率，这意味着这些区域在启动双稳态感知中可能具有因果作用。相比之下，涉及形状和深度处理的区域（外侧枕叶复合体和V3A）对倾斜度敏感，但当这些线索冲突时，活动并未增加。
