Abstract：
OBJECTIVE: While high concentrations of toluene are known to affect multiple human organ systems, research concerning the influence of immediate, short-term exposure to toluene indoors and at low concentrations is scarce. Here, we studied effects of indoor toluene exposure on neural network alterations during working memory (WM) encoding.
METHODS: A total of 23 healthy college students were recruited. All participants were situated in a closed environmental chamber with a full fresh air system. Each participant was subjected to four exposure experiments with different toluene concentrations (0, 17.5, 35, and 70 ppb, named Group A, B, C and D, respectively), with at least one week between each experiment. WM Behavioral and 19-channel electroencephalogram (EEG) recordings in a pre-set environmental chamber were conducted simultaneously during each toluene exposure experiment. Neural networks relevant to WM encoding were visualized analyzing the obtained data.
RESULTS: 1. No significant difference in WM behavioral performance among the four groups was found. However, a significant increase in whole brain neural network functional connectivity was noted, especially in the frontal region. 2. An outflow directional transfer function (DTFoutflow) revealed higher frontal region values among Group D (the 70 ppb group) as compared to Group A, B and C (the0, 17.5 ppb and 35 ppb groups, respectively), although no differences in frontal region DTFinflow values among the four groups were noted. 3. The DTFFZ-F7, DTFFZ-T5, DTFFZ-P4, DTFFZ-P3, DTFFP2-O2, DTFP3-T4, DTFP3-F4, DTFP4-CZ and DTFP4-T4 values of Group D were found to be higher as compared to those of Group A and B. Furthermore, DTFFZ-F7 and DTFP4-T4 values of Group C were higher as compared to those of Group A. The DTFFZ-F7 values of Group D were higher as compared to those of the Group C.
CONCLUSIONS: Short-term toluene exposure significantly influences neural networks during cognitive processes such as WM encoding, even at low concentration.
METHODS: A total of 23 healthy college students were recruited. All participants were situated in a closed environmental chamber with a full fresh air system. Each participant was subjected to four exposure experiments with different toluene concentrations (0, 17.5, 35, and 70 ppb, named Group A, B, C and D, respectively), with at least one week between each experiment. WM Behavioral and 19-channel electroencephalogram (EEG) recordings in a pre-set environmental chamber were conducted simultaneously during each toluene exposure experiment. Neural networks relevant to WM encoding were visualized analyzing the obtained data.
RESULTS: 1. No significant difference in WM behavioral performance among the four groups was found. However, a significant increase in whole brain neural network functional connectivity was noted, especially in the frontal region. 2. An outflow directional transfer function (DTFoutflow) revealed higher frontal region values among Group D (the 70 ppb group) as compared to Group A, B and C (the0, 17.5 ppb and 35 ppb groups, respectively), although no differences in frontal region DTFinflow values among the four groups were noted. 3. The DTFFZ-F7, DTFFZ-T5, DTFFZ-P4, DTFFZ-P3, DTFFP2-O2, DTFP3-T4, DTFP3-F4, DTFP4-CZ and DTFP4-T4 values of Group D were found to be higher as compared to those of Group A and B. Furthermore, DTFFZ-F7 and DTFP4-T4 values of Group C were higher as compared to those of Group A. The DTFFZ-F7 values of Group D were higher as compared to those of the Group C.
CONCLUSIONS: Short-term toluene exposure significantly influences neural networks during cognitive processes such as WM encoding, even at low concentration.
摘要：
目的：虽然已知高浓度的甲苯会影响多个人体器官系统，关于即时影响的研究，在室内和低浓度下短期接触甲苯很少。这里,我们研究了室内甲苯暴露对工作记忆（WM）编码过程中神经网络变化的影响。
方法：招募23名健康大学生。所有参与者都位于带有完整新鲜空气系统的封闭环境室中。每个参与者都接受了不同甲苯浓度（0、17.5、35和70ppb，名为A组,B,C和D,分别)，每个实验之间至少有一周的时间。在每个甲苯暴露实验期间，在预设的环境室中同时进行WM行为和19通道脑电图（EEG）记录。与WM编码相关的神经网络被可视化，分析获得的数据。
结果：1.四组之间的WM行为表现没有显着差异。然而,注意到全脑神经网络功能连通性的显着增加，尤其是在额叶区域。2.流出方向传递函数（DTFoutflow）显示，与A组相比，D组（70ppb组）的额叶区域值较高，B和C(0、17.5ppb和35ppb组，分别)，尽管四组中额叶区DTFinflow值没有差异.3.发现D组的DTFFZ-F7、DTFFZ-T5、DTFFZ-P4、DTFFZ-P3、DTFFP2-O2、DTFP3-T4、DTFP3-F4、DTFP4-CZ和DTFP4-T4值高于A组和B组。C组的DTFFZ-F7和DTFP4-T4值高于A组。D组的DTFFZ-F7值高于C组。即使浓度很低。
方法：招募23名健康大学生。
结果：1.
