National Magnetic Resonance Research Center and Aysel Sabuncu Brain Research Center, Bilkent University, Ankara, Turkey; Graduate School of Engineering and Science, Neuroscience Program, Bilkent University, Ankara, Turkey.
National Magnetic Resonance Research Center and Aysel Sabuncu Brain Research Center, Bilkent University, Ankara, Turkey.
Neuroimage. 2019 Apr 15;190:242-253. doi: 10.1016/j.neuroimage.2018.03.077. Epub 2018 Apr 4.
The occipital lobe contains a substantial part of the neural machinery involved in visual perception. Mutations in the LAMC3 gene have recently been shown to cause complex bilateral occipital cortical gyration abnormalities. However, to what extent these structural changes impact visual behavior is not known. We recorded responses for two screening test batteries targeting visual function (Leuven - Perceptual Organization Screening Test, Cortical Vision Screening Test) and measured eye fixation performance in a visual attention experiment from a patient with homozygous LAMC3 gene mutation. Using voxel-based morphometry (VBM) we quantitatively assessed the extent of structural changes brought on by the genetic mutation by comparing mean cortical curvature, cortical thickness, and gray matter volume in 34 cortical areas between patient and an age-, sex-, and education-matched control group. Anatomical connectivity between these cortical areas was investigated by a structural covariance analysis. Visual screening-, and behavioral results revealed that the patient's impairments were predominantly in visuo-spatial attention. Consistent with this, VBM and structural connectivity results revealed significant structural changes in cortical regions subserving attentional functions. We conclude that the LAMC3 gene mutation affects cortical areas beyond the occipital lobe and primarily those visual functions that involve heavily distributed networks - such as visuo-spatial attention.
枕叶包含了大量参与视觉感知的神经机制。最近的研究表明，LAMC3 基因突变会导致复杂的双侧枕叶皮质回旋异常。然而，这些结构变化在多大程度上影响视觉行为尚不清楚。我们记录了一位 LAMC3 基因纯合突变患者的视觉功能筛查测试（Leuven - 知觉组织筛查测试、皮质视觉筛查测试）的两种测试结果，并在视觉注意力实验中测量了眼动注视性能。我们通过体素形态计量学（VBM）对患者和年龄、性别、教育匹配的对照组之间 34 个皮质区域的平均皮质曲率、皮质厚度和灰质体积进行比较，定量评估了遗传突变带来的结构变化程度。通过结构协方差分析研究了这些皮质区域之间的解剖连接。视觉筛查和行为结果表明，患者的损伤主要在视空间注意力方面。与此一致的是，VBM 和结构连接结果显示，注意力功能相关皮质区域的结构发生了显著变化。我们得出结论，LAMC3 基因突变会影响枕叶以外的皮质区域，主要是那些涉及广泛分布网络的视觉功能，如视空间注意力。
