Binocular disparity, a primary cue for stereoscopic depth perception, is widely represented in visual cortex. However, the functional specialization in the disparity processing network remains unclear. Using magnetic resonance imaging-guided transcranial magnetic stimulation, we studied the causal contributions of V3A and MT+ to stereoscopic depth perception. Subjects viewed random-dot stereograms forming transparent planes with various interplane disparities. Their smallest detectable disparity and largest detectable disparity were measured in two experiments. We found that the smallest detectable disparity was affected by V3A, but not MT+ , stimulation. On the other hand, the largest detectable disparity was affected by both V3A and MT+ stimulation. Our results suggest different roles of V3A and MT+ in stereoscopic depth processing.

双眼视差是立体深度感知的主要提示，在视觉皮层中得到了广泛体现。然而，视差处理网络中的功能专业化仍不清楚。使用磁共振成像引导的经颅磁刺激，我们研究了V3A和MT +对立体深度感知的因果关系。受试者观看了随机点立体图，这些立体图形成了具有各种平面间差异的透明平面。在两个实验中测量了它们的最小可检测差异和最大可检测差异。我们发现最小的可检测差异受V3A刺激，但不受MT +刺激影响。另一方面，V3A和MT +刺激都会影响最大可检测到的差异。我们的结果表明，V3A和MT +在立体深度处理中具有不同的作用。