Chen C H, Ninomiya H, Onitsuka T
Department of Neuropsychiatry, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Psychiatry Clin Neurosci. 1997 Jun;51(3):139-43. doi: 10.1111/j.1440-1819.1997.tb02376.x.
To clarify the nature of auditory P50, middle latency auditory evoked potentials were recorded by using different conditions of reference electrodes (linked earlobes, LE; balanced non-cephalic, BN), stimulation characteristics (tone burst, human voice) and tasks (counting, simple reaction) in 10 right-handed males (aged 21-36 years). EEG was recorded from Fz, Cz, Pz, C3, C4, T3 and T4 according to the 10-20 system. Two groups of electrode sites were made for the statistical analysis: a midline group, Fz, Cz and Pz, and a lateral group, T3, C3, Cz, C4 and T4. The results were that the P50 amplitudes with BN electrodes were significantly higher than those with LE in both groups (midline, P < 0.01; lateral, P < 0.01); the P50 amplitudes by voice stimulation were significantly higher than those by tone stimulation in the lateral group (P < 0.05), and the P50 latencies under a simple reaction paradigm were significantly shorter than those under a counting task in both groups (midline, P < 0.05; lateral, P < 0.05). These results suggest that various factors including motor response affect the P50 amplitudes and latencies.
为阐明听觉P50的本质，对10名右利手男性（年龄21 - 36岁）在不同参考电极条件（耳垂相连，LE；平衡非头侧，BN）、刺激特征（短纯音、人声）和任务（计数、简单反应）下记录了中潜伏期听觉诱发电位。根据10 - 20系统从Fz、Cz、Pz、C3、C4、T3和T4记录脑电图。为进行统计分析设置了两组电极部位：中线组，Fz、Cz和Pz；外侧组，T3、C3、Cz、C4和T4。结果显示，两组中使用BN电极时的P50波幅均显著高于使用LE电极时（中线组，P < 0.01；外侧组，P < 0.01）；外侧组中声音刺激时的P50波幅显著高于短纯音刺激时（P < 0.05），且两组在简单反应范式下的P50潜伏期均显著短于计数任务下的P50潜伏期（中线组，P < 0.05；外侧组，P < 0.05）。这些结果表明，包括运动反应在内的多种因素会影响P50波幅和潜伏期。
