Kakizaki T
National Institute of Industrial Health, Kawasaki, Japan.
Ind Health. 1990;28(2):85-96. doi: 10.2486/indhealth.28.85.
To objectively detect the lowering in mental activity during mental tasks, twenty-five male students were given the calculating tasks of adding or subtracting two 2-digit numbers at three grades of task load for 1 hr each. At any task load there was little variation in the percentage of correct responses in successive 5-min periods. There was no difference among the three task loads in the mood states of stress or arousal rated at the end of the task. Among the six bands in eight leads the amplitude of the beta-2 band in the Oz-A1 lead (Oz beta 2) showed the greatest fall corresponding to a drowsy state in one subject. It was judged from this pattern that mental activity might decrease sporadically in half of the subjects, irrespective of the task load. The mean Oz beta 2 amplitudes for all the task loads decreased with work time.
为了客观检测心理任务期间心理活动的降低情况，25名男学生被给予了在三种任务负荷等级下进行两个两位数加减法的计算任务，每种任务负荷持续1小时。在任何任务负荷下，连续5分钟时间段内正确反应的百分比几乎没有变化。在任务结束时评定的压力或唤醒情绪状态方面，三种任务负荷之间没有差异。在八个导联的六个波段中，Oz - A1导联（Ozβ2）的β2波段振幅下降最大，对应一名受试者的困倦状态。从这种模式判断，无论任务负荷如何，一半受试者的心理活动可能会偶尔下降。所有任务负荷下的Ozβ2平均振幅随工作时间而降低。
