Neuroimaging Study of Second Generation with Polychlorinated Biphenyls Exposure

• Main Authors: Shao-Wei Wu, 吳紹維
• Other Authors: Sung-Tsang Hsieh
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/91271888137463260888

碩士 === 國立臺灣大學 === 腦與心智科學研究所 === 101 === Background and aim: In 1979, there were people poisoned by polychlorinated biphenyls (PCBs) due to ingestion of contaminated cooking oil in Taiwan. The victims were called “Yucheng, oil disease”. Yucheng offspring with indirect transplacenta exposure to PCBs were noticed to have cognitive dysfunction by neuropsychological test since childhood to adolescence in previous studies. This study follows up IQ test in Yucheng offspring, analyses the cerebral functional connectivity and task activated brain networks in functional magnetic resonance image (fMRI). We discuss the relationship of brain functional network and neurocognitive function. Method: 10 Yucheng offspring and 12 health controls undergo Wechsler Adult Intelligence Scale (WAIS) test and brain magnetic resonance image study. We get various brain networks by seed region with posterior cingulate cortex (PCC), left middle temporal motion-sensitive area (MT+), right or left anterior inferior parietal lobule and left inferior frontal sulcus, to analyze the temporal coherence of BOLD signal fluctuation in resting state. Cortical deactivation during working memory task in comparison to control task and functional coupling of spatial attentive areas during spatial attention task are also analyzed. Results: Comparing adult of Yucheng offspring with health controls, no difference in the WAIS score is observed. In working memory task, there is reduced deactivation of medial prefrontal cortex (mPFC) which is an important node in default mode network (DMN). During spatial attention task, there is reduced functional connectivity between regions associated with processing of spatial attention, such as left anterior insula, left middle temporal area and precuneus. As for functional coupling of brain networks in resting state, Yucheng offspring reveal increased connectivity to right inferior parietal lobule (RIPL) in executive attention network, reduced connectivity to left temporoparietal junction (TPJ), left insula, and right supramarginal gyrus in right frontoparietal control network (FPCN) ,as well as reduced connectivity to left middle frontal gyrus in left FPCN. There is no difference in functional connectivity within DMN and language network among two groups. Conclusion: We describe normalization of clinical cognitive function in Yucheng offspring in adulthood, while there is failure to deactivate the mPFC within DMN during executive task and aberrant functional connectivity within various brain networks subclinically. These findings may contribute to the understanding of prenatal PCBs exposure and consequence of neural network change in Yucheng offspring.