实时功能磁共振反馈技术的优化和应用研究

发布时间：2018-06-21 04:59

本文选题：实时功能磁共振 + 神经反馈　；参考：《浙江大学》2017年硕士论文

【摘要】：随着磁共振影像技术广泛地应用于神经科学领域研究,关于大脑的功能分析不断涌现,帮助人们揭示了大脑的奥秘。其中,传统的功能磁共振研究虽然实验设计多种多样,但因其实验业务流程比较固定,在一定程度上限制了实验变量的设定。本文在实现实时功能磁共振闭环回路系统的基础上,以感兴趣区血氧水平依赖(blood oxygen level dependent,BOLD)信号强度作为神经反馈实验设计变量,探索了受试者的自我调控能力对其大脑任务响应程度的影响。同时,结合了多层同时成像技术和局部扫描技术采集方法提高了实时功能磁共振的时间分辨率和空间分辨率,进而缩短了神经反馈的周期,增加了神经反馈的精细性。实验结果表明,经过神经反馈训练的所有受试者相较于对照组都能够明显地抑制大脑额中回感兴趣区对负面情绪图片刺激的响应水平。并且,在综合了普通EPI、multiband-EPI和ZOOMit-EPI序列采集得到的任务实验激活区BOLD信号强度响应的情况下,发现ZOOMit-EPI采集方法能够在激活区提供更高的平静和刺激状态信号强度对比度。改善实验业务流程不但可以拓展研究实验中变量的设计,而且可以帮助提高临床病人的功能任务实验扫描的效率。为此,本文基于实时功能磁共振提出了一种具有实时更新和监控功能的实验任务刺激系统。该系统通过检测受试者的任务实验响应情况帮助主试者判断是否提前无缝切换任务实验至新阶段。该系统不仅可以监测数据的质量,还可以缩短任务实验扫描总时长,具有十分重要的实际应用价值。
[Abstract]:With the wide application of magnetic resonance imaging (MRI) in the field of neuroscience, functional analysis of the brain is emerging, which helps to reveal the mystery of the brain. The traditional functional magnetic resonance (fMRI) study has a variety of experimental designs, but its experimental business process is relatively fixed, which limits the setting of experimental variables to a certain extent. In this paper, based on the realization of real-time functional magnetic resonance closed-loop system, the signal intensity of blood oxygen level dependent Bod in the region of interest is used as the neural feedback experimental design variable. The effects of subjects' self-regulation ability on their brain task response were investigated. At the same time, the time resolution and spatial resolution of real-time fMRI are improved by combining multi-layer simultaneous imaging technique and local scanning technique, and the period of neural feedback is shortened and the fineness of neural feedback is increased. The results showed that all subjects trained with neural feedback could significantly inhibit the response level of the region of interest in frontal gyrus to the stimulation of negative emotional images compared with the control group. Furthermore, under the condition of synthesizing the signal intensity response of the activation region of the task experiment obtained from the common EPII-multiband-EPI and ZOOMit-EPI sequences, it is found that the ZOOMit-EPI acquisition method can provide a higher calm and contrast of the signal intensity of the stimulus state in the activation region. Improving the experimental business process can not only expand the design of the variables in the research experiment, but also help to improve the efficiency of the functional task experimental scanning of the clinical patients. Therefore, based on real-time functional magnetic resonance, an experimental task stimulation system with real-time updating and monitoring function is proposed. The system can help the subjects to decide whether to switch tasks seamlessly to the new stage by detecting the subjects' response to the task experiment. The system can not only monitor the quality of data, but also shorten the total scanning time of task experiment. It has very important practical application value.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP274;R445.2

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