Harding G F, Degg C, Anderson S J, Holliday I, Fylan F, Barnes G, Bedford J
Department of Vision Sciences, Aston University, Birmingham, UK.
Int J Psychophysiol. 1994 May;16(2-3):175-83. doi: 10.1016/0167-8760(89)90044-5.
Visual evoked magnetic responses to pattern onset/offset stimuli were recorded in 5 normal subjects. The outgoing and ingoing magnetic currents were seen maximally over the contralateral visual cortex to the half field stimulated in the majority of subjects. The distribution of magnetic currents with half field stimulation would be consistent with a dipole on the midline with the positive end pointing laterally. Quadrantic stimuli produced dipoles which would be consistent with a vector sum of dipoles situated, in the case of upper quarter field stimulation, in the lingual gyri on the floor of the calcarine fissure. Lower quadrantic stimulation produced a vector consistent with dipoles on the cuneal gyrus and on the ceiling of the calcarine fissure producing a resultant vector. The use of paired octant stimuli to improve localisation was demonstrated on both right left and upper and lower half fields.
对5名正常受试者记录了对图形起始/偏移刺激的视觉诱发电磁反应。在大多数受试者中，传出和传入磁电流在与受刺激半视野对侧的视觉皮层上显示最大。半视野刺激时磁电流的分布与位于中线的偶极子一致，其正极指向外侧。象限刺激产生的偶极子与偶极子的矢量和一致，在上象限视野刺激的情况下，这些偶极子位于距状裂底部的舌回中。下象限刺激产生的矢量与楔回和距状裂顶部的偶极子一致，从而产生一个合成矢量。在左右半视野和上下半视野上都证明了使用配对八分视野刺激来改善定位。
