在人体V1损伤后,与训练恢复对比度敏感度的有限恢复
Jingyi Yang 杨菁艺1,2,3, Elizabeth L Saionz1,3, Matthew R Cavanaugh1,3
1Flaum Eye Institute, University of Rochester Medical Center, Rochester, New York 14642.
eNeuro
|February 23, 2024
概括
对主要视觉皮层的中风损伤严重损害了对比度的敏感性. 虽然感知训练有助于一些患者,特别是在中风后的早期,但它并不能完全恢复正常视力,这表明V1是V1.
科学领域:
- 神经科学是一个神经科学.
- 视觉科学 视觉科学 视觉科学
- 临床神经学 临床神经学
背景情况:
- 从中风造成的初级视觉皮层 (V1) 损伤会导致显著的视觉缺陷.
- 感知再训练可以改善一些视觉功能,但对比度敏感度的恢复是有限的.
- 在中风后的盲场中,高对比的视觉能力可能会被保留.
研究的目的:
- 调查V1冲击后在盲场中对方向和运动歧视的对比度敏感度 (CS) 的保存和可训练性.
- 为了比较亚急性和慢性中风患者的结果.
主要方法:
- 评估了13名亚急性 (<3个月) 和12名慢性 (>6个月) V1中风患者.
- 参与者接受了培训,以在逐渐较低的对比度下区分Gabor补丁的方向或运动方向.
- 评估了在盲人领域的基线和训练后的表现.
主要成果:
- 亚急性患者在盲场中比慢性患者更好地显示出基线导向歧视,但所有患者在低对比度下都失败了.
- 训练改善了CS在更多的亚急性比慢性参与者,但正常的CS没有达到任何病人.
- 在亚急性患者中,对静态目标的导向歧视的改善更为明显.
结论:
- V1损伤严重限制了中风后恢复正常的对比度灵敏度,与高对比度区分能力不同.
- 在V1损坏的视觉系统中,对比敏感性依赖于不同的神经基质,而不是方向和运动歧视.
- 感知训练对完全恢复V1中风后对比度敏感性的潜力有限,特别是在慢性患者中.
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