Pardo J V, Fox P T, Raichle M E
Department of Psychiatry, Washington University Medical Center, St. Louis, Missouri 63110.
Nature. 1991 Jan 3;349(6304):61-4. doi: 10.1038/349061a0.
Positron emission tomographic (PET) studies of human attention have begun to dissect isolable components of this complex higher brain function, including a midline attentional system in a region of the anterior cingulate cortex. The right hemisphere may play a special part in human attention; neglect, an important phenomenon associated with damage to attentional systems, is more severe, extensive and long-lasting after lesions to the right hemisphere. Here we use PET measurements of brain blood flow in healthy subjects to identify changes in regional brain activity during simple visual and somatosensory tasks of sustained attention or vigilance. We find localized increases in blood flow in the prefrontal and superior parietal cortex primarily in the right hemisphere, regardless of the modality or laterality of sensory input. The anterior cingulate was not activated during either task. These data localize the vigilance aspects of normal human attention to sensory stimuli, thereby clarifying the biology underlying asymmetries of attention to such stimuli that have been reported in clinical lesions.
对人类注意力的正电子发射断层扫描（PET）研究已开始剖析这种复杂的高级脑功能中可分离的组成部分，包括前扣带回皮质区域的中线注意力系统。右半球可能在人类注意力中发挥特殊作用；忽视是与注意力系统损伤相关的一个重要现象，在右半球受损后更为严重、广泛且持久。在此，我们利用PET对健康受试者脑血流的测量，来识别在持续注意力或警觉的简单视觉和躯体感觉任务期间区域脑活动的变化。我们发现，无论感觉输入的方式或偏向如何，主要在右半球的前额叶和顶上皮质区域血流出现局部增加。在这两项任务中，前扣带回均未被激活。这些数据将正常人类对感觉刺激的注意力警觉方面定位下来，从而阐明了临床损伤中所报告的对这类刺激的注意力不对称现象背后的生物学机制。
