Herwig Uwe, Satrapi Peyman, Schönfeldt-Lecuona Carlos
Department of Psychiatry, University of Ulm, Germany.
Brain Topogr. 2003 Winter;16(2):95-9. doi: 10.1023/b:brat.0000006333.93597.9d.
The International 10-20 system for EEG electrode placement is increasingly applied for the positioning of transcranial magnetic stimulation (TMS) in cognitive neuroscience and in psychiatric treatment studies. The crucial issue in TMS studies remains the reliable positioning of the coil above the skull for targeting a desired cortex region. In order to asses the precision of the 10-20 system for this purpose, we tested its projections onto the underlying cortex by using neuronavigation.
In 21 subjects, the 10-20 positions F3, F4, T3, TP3, and P3, as determined by a 10-20 positioning cap, were targeted stereotactically. The corresponding individual anatomical sites were identified in the Talairach atlas.
The main targeted regions were: for F3 Brodmann areas (BA) 8/9 within the dorsolateral prefrontal cortex, for T3 BA 22/42 on the superior temporal gyrus, for TP3 BA 40/39 in thearea of the supramarginal and angular gyrus, and for P3 BA 7/40 on the inferior parietal lobe. However, in about 10% of the measurements adjacent and possibly functionally distinct BAs were reached. The ranges were mainly below 20 mm.
Using the 10-20 system for TMS positioning is applicable at low cost and may reach desired cortex regions reliably on a larger scale level. For finer grained positioning, possible interindividual differences, and therefore the application of neuroimaging based methods, are to be considered.
国际10 - 20脑电图电极放置系统越来越多地应用于认知神经科学和精神治疗研究中的经颅磁刺激（TMS）定位。TMS研究中的关键问题仍然是将线圈可靠地放置在颅骨上方以靶向所需的皮质区域。为了评估10 - 20系统在此目的上的精度，我们使用神经导航测试了其在下层皮质上的投影。
在21名受试者中，通过10 - 20定位帽确定的10 - 20位置F3、F4、T3、TP3和P3进行立体定向靶向。在Talairach图谱中识别相应的个体解剖部位。
主要靶向区域为：F3对应背外侧前额叶皮质内的布罗德曼区（BA）8/9，T3对应颞上回的BA 22/42，TP3对应缘上回和角回区域的BA 40/39，P3对应顶下叶的BA 7/40。然而，在约10%的测量中，到达了相邻且可能功能不同的BA。范围主要在20毫米以下。
使用10 - 20系统进行TMS定位成本低且可大规模可靠地到达所需的皮质区域。对于更精细的定位，应考虑个体间可能存在的差异，因此需考虑应用基于神经成像的方法。
