Sultan Fahad, Augath Mark, Logothetis Nikos
Department of Cognitive Neurology, HIH for Clinical Brain Research, University Tuebingen, 72076 Tuebingen, Germany.
Magn Reson Imaging. 2007 Jul;25(6):754-9. doi: 10.1016/j.mri.2007.03.014. Epub 2007 May 4.
Electrical microstimulation via intracortical electrodes is a widely used method for deducing functions of the brain. In this study, we compared the spatial extent and amplitude of BOLD responses evoked by intracortical electrical stimulation in primary visual cortex with BOLD activations evoked by visual stimulation. The experiments were performed in anesthetized rhesus monkeys. Visual stimulation yielded activities larger than predicted from the well-established visual magnification factor. However, electrical microstimulation yielded an even greater spread of the BOLD response. Our results confirm that the effects of electrical microstimulation extend beyond the brain region expected to be excited by direct current spread.
通过皮层内电极进行电微刺激是一种广泛用于推断大脑功能的方法。在本研究中，我们比较了初级视觉皮层中皮层内电刺激诱发的BOLD反应的空间范围和幅度与视觉刺激诱发的BOLD激活。实验在麻醉的恒河猴身上进行。视觉刺激产生的活动大于根据已确立的视觉放大因子预测的活动。然而，电微刺激产生的BOLD反应扩散甚至更大。我们的结果证实，电微刺激的影响超出了预期因直流电扩散而被兴奋的脑区。
