黑白棋盘格视觉刺激源时BOLD响应对闪烁频率的非依赖性

目的研究视觉刺激的闪烁频率与BOLD响应之间的关系.材料与方法通过磁共振功能成像(fMRI)的方法,在黑白棋盘格视觉刺激源的切换频率从4～14Hz范围内,在初级视觉皮层(V1)区内分别测量BOLD响应.结果BOLD信号幅度的变化在4～14Hz内基本相同,但是在V1区内激活像元数显示出频率依赖性.结论BOLD信号对视觉刺激频率的依赖性可能受视觉刺激类型的影响.

Frequency-Independent BOLD Response to Reversing Checkerboard Stimulation Observed in Human Primary Visual Cortex Using fMRI

Purpose: This study aimed to examine the relationship between the BOLD response in human primary visual cortex and temporal frequency by pressenting a black and white reversing checkerboard. Materials and Methods: The blood oxygenation level dependent (BOLD) response to a black and white checkerboard at various reversing frequencies between 4 Hz and 14 Hz was measured in the primary visual cortex using functional magnetic resonance imaging (fMRI). Results: It was found that the amplitude of the BOLD signal was approximately the same for all frequencies in this range but the averaged number of activated pixels showed frequency dependent within the primary visual cortex. Conclusion: This study may suggest that BOLD response depended on the temporal frequency could be influenced by visual stimulus pattern.