Qihong Zou1, 2, Hong Gu2, Jiongjiong Wang3, Jia-Hong Gao1, 4, Yihong Yang2
1MRI Research Center and Beijing City Key Lab for Medical Physics and Engineering, Peking University, Beijing, China; 2Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States; 3Department of Neurology, University of California Los Angeles, Los Angeles, CA, United States; 4Brain Research Imaging Center, University of Chicago, Chicago, IL, United States
Brain activation and deactivation induced by N-back working memory tasks and load effects have been investigated using PET and BOLD fMRI. However, mechanisms of BOLD fMRI are not completely understood and PET requires injection of radioactive tracers. Here, a pCASL technique was used to quantify CBF, a well understood index reflective of cerebral metabolism. We showed activation in fronto-parietal cortices and deactivation in PCC and MPFC during working memory tasks. Most of the activated/deactivated brain regions showed approximately linear relationship between CBF and task loads. These results demonstrate feasibility of ASL techniques to quantify brain activity during high cognitive tasks.