Orientation-tuned fMRI adaptation in human visual cortex
Orientation-tuned fMRI adaptation in human visual cortex
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DOI：
10.1152/jn.00378.2005
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发表时间：
2005-12-01
影响因子：
2.5
通讯作者：
He, S
中科院分区：
文献类型：
--
作者：
Fang, F;Murray, SO;He, S
方，方，斯科特·O·默里，丹尼尔·克斯滕，何盛。人类视觉皮层的方向调整功能磁共振成像适应。 《神经生理学杂志》94：4188-4195，2005 年。首次发表于 2005 年 8 月 24 日； doi：10.1152/jn。 00378.2005。适应是几乎所有神经系统的普遍属性，并且一直是心理物理学的长期工具，因为它具有隔离和暂时减少特定神经群体的贡献的能力。最近，适应设计已广泛应用于功能磁共振成像（fMRI）研究中，以推断特定皮质区域的神经选择性。然而，这些实验中使用的适应持续时间存在相当大的变化。特别是，尽管长期适应已在心理物理学和神经生理学研究中得到牢固确立，但它已被纳入很少的功能磁共振成像研究中。此外，使用具有众所周知的适应性特性（例如方向）的刺激维度和在更好理解的皮层区域（例如初级视觉皮层，V1）中对功能磁共振成像适应性的验证很少。我们使用事件相关的功能磁共振成像实验来研究人类视觉皮层的长期定向适应。在长期适应定向模式后，V1、V2、V3/VP、V3A 和 V4 对测试刺激的 fMRI 响应与适应刺激和测试刺激之间的角度差成正比。然而，只有V3A和V4表现出这种短期适应的反应模式。在另一个实验中，我们测量了适应后的行为对比检测阈值，发现 V1 中的 fMRI 信号与心理物理学得出的对比检测阈值密切匹配。与功能磁共振成像结果类似，适应引起的阈值变化很大程度上取决于适应的持续时间。除了支持人类视觉皮层中存在适应性定向调节神经元之外，我们的结果还表明在功能磁共振成像适应实验中考虑时序参数的重要性。
Fang, Fang, Scott O. Murray, Daniel Kersten, and Sheng He. Orientation-tuned fMRI adaptation in human visual cortex. J Neurophysiol 94: 4188-4195, 2005. First published August 24, 2005; doi: 10.1152/jn. 00378.2005. Adaptation is a general property of almost all neural systems and has been a longstanding tool of psychophysics because of its power to isolate and temporarily reduce the contribution of specific neural populations. Recently, adaptation designs have been extensively applied in functional MRI (fMRI) studies to infer neural selectivity in specific cortical areas. However, there has been considerable variability in the duration of adaptation used in these experiments. In particular, although long-term adaptation has been solidly established in psychophysical and neurophysiological studies, it has been incorporated into few fMRI studies. Furthermore, there has been little validation of fMRI adaptation using stimulus dimensions with well-known adaptive properties (e.g., orientation) and in better understood regions of cortex (e.g., primary visual cortex, V1). We used an event-related fMRI experiment to study long-term orientation adaptation in the human visual cortex. After long-term adaptation to an oriented pattern, the fMRI response in V1, V2, V3/VP, V3A, and V4 to a test stimulus was proportional to the angular difference between the adapting and test stimuli. However, only V3A and V4 showed this response pattern with short-term adaptation. In a separate experiment, we measured behavioral contrast detection thresholds after adaptation and found that the fMRI signal in V1 closely matched the psychophysically derived contrast detection thresholds. Similar to the fMRI results, adaptation induced threshold changes strongly depended on the duration of adaptation. In addition to supporting the existence of adaptable orientation-tuned neurons in human visual cortex, our results show the importance of considering timing parameters in fMRI adaptation experiments.