How abnormal visual experiences early in life influence human subcortical pathways is poorly understood. Using high-resolution fMRI and pathway-selective visual stimuli, we investigate the influence of amblyopia on response properties and the effective connectivity of subcortical visual pathways of the adult human brain. Compared to the normal and fellow eyes, stimuli presented to the amblyopic eye show selectively reduced response in the parvocellular layers of the lateral geniculate nucleus and weaker effective connectivity to V1. Compared to the normal eye, the response of the amblyopic eye to chromatic stimulus decreases in the superficial layers of the superior colliculus, while response of the fellow eye robustly increases in the deep SC with stronger connectivity from the visual cortex. Therefore, amblyopia leads to selective parvocellular alterations of the geniculostriate and corticotectal pathways. These findings provide the neural basis for amblyopic deficits in visual acuity, ocular motor control, and attention.

人们对生命早期的异常视觉体验如何影响人类皮层下通路知之甚少。我们使用高分辨率 fMRI 和通路选择性视觉刺激，研究弱视对成人大脑的反应特性和皮层下视觉通路的有效连通性的影响。与正常眼和对侧眼相比，弱视眼的刺激表现出选择性降低外侧膝状体核的小细胞层的反应，并且与 V1 的有效连接性较弱。与正常眼睛相比，弱视眼对色刺激的反应在上丘浅层减少，而对侧眼的反应在深部 SC 强烈增加，视觉皮层的连接性更强。所以，弱视导致膝纹状体和皮质顶盖通路的选择性细小细胞改变。这些发现为视力、眼球运动控制和注意力方面的弱视缺陷提供了神经基础。