Sakatani K, Lichty W, Xie Y, Li S, Zuo H
Department of Neurosurgery, China-Japan Friendship Hospital, Beijing, China; Department of Rehabilitation, China-Japan Friendship Hospital, Beijing, China; Group of Detection & Analysis of Human Body Movement, Program of Biomedical Engineering, Department of Electrical Engineering, Tsinghua University, Beijing, China; Department of Neurology, Beijing Union Hospital, Beijing, China.
J Stroke Cerebrovasc Dis. 1999 Nov-Dec;8(6):398-403. doi: 10.1016/s1052-3057(99)80047-0.
The use of positron-emission tomography (PET) has shown a variety of age-related alterations in neuronal activity in elderly patients. Near infrared spectroscopy (NIRS) has shown a multiplicity of evoked cerebral blood oxygenation (CBO) changes during cognitive performance. To evaluate the effects of aging on the CBO changes, we compared the CBO changes induced by cognitive tasks between young adults and older adults by using NIRS. Twenty-six participants performed 6 cognitive tasks to evaluate differences among young adults (mean age+/-SD, 28.8+/-4.4 years) and older adults (50.7+/-8.0 years). We monitored CBO changes in the left prefrontal cortex. We classified several common patterns of the NIRS parameter change and compared the frequency of each pattern in both groups. In both groups, the most common NIRS parameter change was an increase in oxyhemoglobin (Oxy-Hb) and total-hemoglobin (Total-Hb), with a decrease in deoxyhemoglobin (Deoxy-Hb). The frequency of this pattern in the older group, however, was considerably lower than in the young group (P<.01). In addition, decreases of Oxy-Hb and Total-Hb during the tasks were more common in the older groups, (P<.0001), suggesting a decrease of regional cerebral blood flow during the tasks. Age effects varied for specific tasks, with results being significant for verbal fluency and reading, (P<.05). During all tasks, older subjects were less likely than younger subjects to have the typical pattern of increases in Oxy-Hb and Total-Hb. In addition, compared with younger subjects, older subjects had a greater frequency of decreases in Oxy-Hb and Total-Hb. The overall results, as well as results for specific tasks, suggest that functional reorganization or alteration of CBO responses may occur during aging.
正电子发射断层扫描（PET）的应用显示，老年患者的神经元活动存在多种与年龄相关的变化。近红外光谱（NIRS）显示，在认知活动期间，诱发的脑血氧合（CBO）会发生多种变化。为了评估衰老对CBO变化的影响，我们使用NIRS比较了年轻人和老年人在认知任务诱发下的CBO变化。26名参与者进行了6项认知任务，以评估年轻人（平均年龄±标准差，28.8±4.4岁）和老年人（50.7±8.0岁）之间的差异。我们监测了左前额叶皮层的CBO变化。我们对NIRS参数变化的几种常见模式进行了分类，并比较了两组中每种模式的出现频率。在两组中，最常见的NIRS参数变化是氧合血红蛋白（Oxy-Hb）和总血红蛋白（Total-Hb）增加，脱氧血红蛋白（Deoxy-Hb）减少。然而，这种模式在老年组中的出现频率明显低于年轻组（P<0.01）。此外，任务期间Oxy-Hb和Total-Hb的减少在老年组中更为常见（P<0.0001），这表明任务期间局部脑血流量减少。年龄效应因特定任务而异，在言语流畅性和阅读方面结果显著（P<0.05）。在所有任务中，老年受试者比年轻受试者更不容易出现Oxy-Hb和Total-Hb增加的典型模式。此外，与年轻受试者相比，老年受试者Oxy-Hb和Total-Hb减少的频率更高。总体结果以及特定任务的结果表明，衰老过程中可能会发生CBO反应的功能重组或改变。
