Effect of Default Mode Network on FMRI Analyses of Addition Calculation

• Main Authors: Tzu-Yi Hong, 洪慈憶
• Other Authors: Tzu-Chen Yeh
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/64652697294638608604

碩士 === 國立陽明大學 === 腦科學研究所 === 98 === In previous studies of functional magnetic resonance imaging, the central correlates of mathematical calculation showed the tripartite system involving bilateral lateral parietal lobes, bilateral middle and superior frontal regions. The spatial template of the default-mode network (DMN) included bilateral medial prefrontal cortice, bilateral posterior cingulate cortice, bilateral inferior parietal lobes, bilateral medial temporal lobes, and bilateral parahippocampal regions. Meta-analysis results showed co-localization of bilateral parietal regions by comparing to meta-analysis of DMN and constructed DMN template of fMRI. The hypothesis of this study was existing interactions of mathematical calculation and DMN in fMRI analyses. In other words, DMN may interfere the fMRI analyses of mathematical calculation. So we use behavioral and fMRI approaches to clarify interactions of neural correlates in addition calculation and DMN. The behavioral experiment of addition was performed for selecting the materials optimal for fMRI, and recording reaction time and the accuracy rate. Effect of DMN on the functional correlates of addition calculation was analyzed using the DMN template-based independent component analysis (TB-ICA). The performance of males was better than females in reaction time of behavioral test for addition condition. Effect of DMN on detecting neural correlates of addition calculation was demonstrated by removal of DMN from the original functional data. Alternation of bilateral parietal activation (especially right side) at (44, -52, 52) appeared after DMN removal. False positive interpretation of previous publish literatures was suggested at regional parietal lobes as indicated by present results.