Central luminance flicker can activate peripheral retinotopic representation
Central luminance flicker can activate peripheral retinotopic representation
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DOI：
10.1016/j.neuroimage.2006.08.029
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发表时间：
2007-01-01
期刊：
影响因子：
5.7
通讯作者：
Vanni, Simo
中科院分区：
文献类型：
--
作者：
Stenbacka, Linda;Vanni, Simo
目的是研究不同条件下大脑皮层对均匀亮度刺激的反应。我们用亮度闪烁和棋盘格图案对比的反转来刺激中央视野，并绘制了视野表现为偏心50度的图。结果表明，当视觉刺激包含黑暗环境下的平均亮度变化时，皮层BOLD反应呈扩张性，而当刺激环境有明亮照明时，皮层BOLD反应无扩张性。在两种刺激设置中，没有皮层区域对亮度闪烁比模式反转更敏感。我们认为视网膜皮质区域亮度反应的扩散是由眼内光散射引起的。在眼睛内部散射的光在视网膜上传播视觉刺激，当刺激的周围是黑暗时，散射光的对比度最强。杂散光是视觉实验中潜在的、经常被忽视的伪影来源，杂散光的响应可能被错误地解释为局部皮层对亮度的敏感性指标。(c) 2006爱思唯尔公司版权所有。
We aimed to study cortical responses to uniform luminance stimulus in different conditions. We stimulated the central visual field with luminance flicker and reversal of checkerboard pattern contrast and mapped the visual field representation up to 50 degrees of eccentricity. Our results show spreading of cortical BOLD responses when visual stimulus contains mean luminance change in dark surround and no spreading when the stimulus surround has bright illumination. No cortical region was more sensitive to luminance flicker than to pattern reversal during both stimulation setups. We suggest that the spread of luminance responses in retinotopic cortical areas results from intraocular scattering of light. Light scattered inside the eye spreads visual stimulation on the retina, and the contrast of the scattered light is strongest when the surround of the stimulus is dark. The stray light is potential and often neglected source of an artefact in visual experiments, and the responses due to stray light can erroneously be interpreted as indicators for local cortical sensitivity to luminance. (c) 2006 Elsevier Inc. All rights reserved.