The FMRI Study Of Basic Chinese Character And Pattern N-back Working Memory In Normal Individual

Memory is an ability to store and recollection new information, which is important for cognize and accommodate. Through the processes of learning, remembering, thinking, solving problems and so on, human need a cognitive system for the on-line retention, temporary storage, maintenance and manipulation of remembered information which has been described and discussed as working memory. The new technique of functional magnetic resonance imaging was used to study the effects of learning on cortical organization in humans. Blood oxygenation level dependent (BOLD) contrast imaging of human brain function gives good freedom from motion artifact, high SNR/unit time, and adequate spatial and time resolution. Because this method is entirely non-invasive, it can be repeated with individual subjects as often as desired and associated with the three elements of function, image and anatomy. These merits make fMRI-BOLD become a new approach in working memory research. And studing human brain using fMRI-BOLD would be the focus in the area of cognitive neuroscience.Objective:To study the feature of brain fMRI-BOLD during the basic Chinese character and pattern n-back working memory task in normal subjects.Methods:20 normal subjects (10 male, 10 female, mean age 26.7, range from 21 to 29 years old) received fMRI-BOLD with the basic Chinese character and pattern n-back working memory tasks, and a 0-back task as control. Statistical analysis and result display of data were performed by SPM2. Behavioral performance including reaction time and accuracy were recorded and performed by using one sample t-tests of basic model.Results:1. Behavior results:(1) Performance accuracy for 0, 2-back basic Chinese character working memory in normal subjects was 99.07%, 93.06% respectively;(2) Performance accuracy for 0, 2-back basic pattern n-back working memory task in normal subjects was 98.61%, 90.43% respectively; 2. fMRI-BOLD results:(1) The n-back basic Chinese character of working memory task:Following brain cortical areas can be found significant activation: left inferior frontal gyrus (BA 46), left inferior temporal gyrus (BA 37), left inferior parietal lobule (BA 40); right middle frontal gyrus (BA 10), right inferior frontal gyrus (BA 47), right medial frontal gyrus (BA 6), right superior parietal lobule (BA 7).(2) The n-back basic pattern of working memory task:Following brain cortical areas can be found significant activation: left middle frontal gyrus (BA 6), left inferior frontal gyrus (BA 47), left inferior parietal lobule (BA 40); right middle frontal gyrus (BA 9), right medial frontal gyrus (BA 8), right extranuclear gray matter (BA13), right inferior parietal lobule (BA40).3. Conclusion:(1) The prefrontal lobe play an important role in working memory. The parietal lobe which is also relative with working memory and play an very important role.(2) Brain domains related to working memory of Chinese character is different from the working memory of alphabetic foreigns; and the dominant hemisphere may located at right hemisphere of brain.(3) Brain domains related to working memory of Chinese character is different from the working memory of pattern.