CAJ | 학술논문

为了实现任务态fMRI的嗅觉刺激装置的设计和功能验证．满足嗅觉fMRI实验的自动化刺激要求．首先，针对嗅觉刺激和人体嗅觉感受的特点，结合使用环境的要求，总结嗅觉fMRI的实验设计方法，归纳出用于fMRI的嗅觉刺激装置的具体需求．将刺激装置分为气路系统和控制系统、气路系统采用洁净空气通过气味溶液产生相应的气味气体，通过多支路切换达到输出不同气味的目的；控制系统采用虚拟仪器方案，其软件基于LabVIEW平台编程，提供可输入刺激序列的人机界面，并根据要求控制电磁阀切换不同气路．然后，使用该刺激装置对单个被试进行嗅觉刺激并成像，刺激气体采用乙酸异戊酯和吡啶，实验为组块设计，使用Siemens 3.0 T MRI仪器EPI序列进行扫描，数据处理采用基于Matlab软件的SPM8和MarsBaR工具包．选取眶额叶和岛叶中的脑激活团簇作为感兴趣区域(ROI)进行分析，激活信号在时间上的强度变化与刺激序列变化基本一致，吡啶组块的激活信号强度大于乙酸异戊酯组块激活强度，且其强度变化比乙酸异戊酯组块更符合刺激序列．ROI分析证明刺激装置基本满足嗅觉fMRI实验需要，具有较强的可用性．此外，在相同的刺激时间和间隔时间下，人脑同一区域对不同刺激气味的激活反应可能不同．
위료실현임무태fMRI적후각자격장치적설계화공능험증．만족후각fMRI실험적자동화자격요구．수선，침대후각자격화인체후각감수적특점，결합사용배경적요구，총결후각fMRI적실험설계방법，귀납출용우fMRI적후각자격장치적구체수구．장자격장치분위기로계통화공제계통、기로계통채용길정공기통과기미용액산생상응적기미기체，통과다지로절환체도수출불동기미적목적；공제계통채용허의의기방안，기연건기우LabVIEW평태편정，제공가수입자격서렬적인궤계면，병근거요구공제전자벌절환불동기로．연후，사용해자격장치대단개피시진행후각자격병성상，자격기체채용을산이무지화필정，실험위조괴설계，사용Siemens 3.0 T MRI의기EPI서렬진행소묘，수거처리채용기우Matlab연건적SPM8화MarsBaR공구포．선취광액협화도협중적뇌격활단족작위감흥취구역(ROI)진행분석，격활신호재시간상적강도변화여자격서렬변화기본일치，필정조괴적격활신호강도대우을산이무지조괴격활강도，차기강도변화비을산이무지조괴경부합자격서렬．ROI분석증명자격장치기본만족후각fMRI실험수요，구유교강적가용성．차외，재상동적자격시간화간격시간하，인뇌동일구역대불동자격기미적격활반응가능불동．
We developed a computer-controlled olfactometer for delivering odors for functional magnetic resonance imaging (fMRI) experiments. The olfactometer is consisted of an air transport system and a control system. Odors are produced and delivered by the air transport system, in which air flow first passes through liquid mixed with odorants in gas-washing bottles and then is delivered to the test subjects. The control system provides a user interface for operating the device and controlling solenoid valves. The system is based on virtual instrumentation technology, and the software for it is written in LabVIEW. The device was tested on a Siemens 3.0 T MRI scanner. Block-design fMRI data were collected from one healthy subject who was stimulated with two odors, isoamyl acetate and pyridine. The raw fMRI data were processed with Matlab-based SPM8 and MarsBaR toolbox. Region-of-interest (ROI)-based analysis was performed for the left orbitofrontal cortex and left insula. It was found that the signal changes in the two ROIs were basically in compliance with the stimulation paradigm, but the signal changes induced by pyridine were more robust than that produced by isoamyl acetate stimulation. In the same ROI, the signal intensity changes caused by pyridine were higher than that induced by isoamyl acetate.