DYNAMIC MAPPING OF THE HUMAN VISUAL-CORTEX BY HIGH-SPEED MAGNETIC-RESONANCE-IMAGING
DYNAMIC MAPPING OF THE HUMAN VISUAL-CORTEX BY HIGH-SPEED MAGNETIC-RESONANCE-IMAGING
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DOI：
10.1073/pnas.89.22.11069
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发表时间：
1992-11-15
影响因子：
11.1
通讯作者：
SHULMAN, RG
中科院分区：
文献类型：
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作者：
BLAMIRE, AM;OGAWA, S;SHULMAN, RG
我们报告使用高速磁共振成像来跟踪闪烁棋盘刺激刺激期间人类视觉皮层图像强度的变化。测量是在 2.1-T、1 米直径的磁铁中进行的，该磁铁是 Bruker Biospec 光谱仪的一部分，我们已对其进行编程以进行平面回波成像。使用直径 15 厘米的表面线圈来发送和接收信号。图像是在 2 秒至 180 秒的刺激期间获取的。图像在 65.5 毫秒内采集到 10 毫米切片，面内体素大小为 6 x 3 毫米。重复时间 (T(R)) 通常为 2 秒，但对于长闪烁周期，使用 T(R) = 8 秒。体素位于以 2 x 2 mm 面内分辨率拍摄的反演恢复图像上。刺激发生后图像强度增加。相对于刺激前水平 (DELTAS/S) 的信号平均变化为 9.7% (SD = 2.8%, n = 20)，回波时间为 70 ms。无论刺激的周期如何，磁共振信号强度的增加相对于刺激都有延迟。每个方案从刺激开始测量的平均延迟如下：2 秒刺激，延迟 = 3.5 秒（SD = 0.5 秒，n = 10）（延迟超过刺激持续时间）； 20 至 24 秒刺激，延迟 = 5 秒（SD = 2 秒，n = 20）。
We report the use of high-speed magnetic resonance imaging to follow the changes in image intensity in the human visual cortex during stimulation by a flashing checkerboard stimulus. Measurements were made in a 2.1-T, 1-m-diameter magnet, part of a Bruker Biospec spectrometer that we had programmed to do echo-planar imaging. A 15-cm-diameter surface coil was used to transmit and receive signals. Images were acquired during periods of stimulation from 2 s to 180 s. Images were acquired in 65.5 ms in a 10-mm slice with in-plane voxel size of 6 x 3 mm. Repetition time (T(R)) was generally 2 s, although for the long flashing periods, T(R) = 8 s was used. Voxels were located onto an inversion recovery image taken with 2 x 2 mm in-plane resolution. Image intensity increased after onset of the stimulus. The mean change in signal relative to the prestimulation level (DELTAS/S) was 9.7% (SD = 2.8%, n = 20) with an echo time of 70 ms. Irrespective of the period of stimulation, the increase in magnetic resonance signal intensity was delayed relative to the stimulus. The mean delay measured from the start of stimulation for each protocol was as follows: 2-s stimulation, delay = 3.5 s (SD = 0.5 s, n = 10) (the delay exceeds stimulus duration); 20- to 24-s stimulation, delay = 5 s (SD = 2 s, n = 20).