Harding G F, Boylan C, Clement R A
Doc Ophthalmol. 1986 Jan 31;62(1):81-8. doi: 10.1007/BF00140550.
Albinism is a congenital condition in which hypopigmentation occurs. In addition to this abnormality there is a misrouting of the optic nerve fibers, with some fibers from the temporal retina following a crossed route at the chiasma and terminating in the contralateral cortical hemisphere. This contralateral preponderance of fibers from each eye should be recognizable from recording the visual evoked cortical potential over each hemisphere on monocular stimulation. Such a technique should produce evidence of responses of either increased amplitude or shorter latency over the contralateral hemisphere. Twenty-five human albinos (twenty-three oculocutaneous, two ocular) have been examined. Pattern appearance-disappearance visual evoked cortical potentials were used, but only on bioccipital derivations did these show clear lateralization. With the flash response the P2 component has a consistently shorter latency over the contralateral hemisphere to the eye stimulated. The visual evoked subcortical potential shows contrasting lateralization. The implications of these findings are discussed.
白化病是一种出现色素减退的先天性疾病。除了这种异常外，还存在视神经纤维的错路，一些来自颞侧视网膜的纤维在视交叉处走交叉路径，并终止于对侧皮质半球。通过在单眼刺激时记录每个半球的视觉诱发电位皮质电位，应该可以识别出每只眼睛纤维的这种对侧优势。这种技术应该能产生对侧半球上反应幅度增加或潜伏期缩短的证据。对25名白化病患者（23名眼皮肤型、2名眼型）进行了检查。使用了图形出现-消失视觉诱发电位皮质电位，但只有在双侧枕部导联时才显示出明显的偏侧化。对于闪光反应，P2成分在受刺激眼对侧的半球上潜伏期始终较短。视觉诱发的皮质下电位显示出相反的偏侧化。讨论了这些发现的意义。
