Development Of Artifact-free Imaging System And FMRI Research Paradigm For Creative Thinking In An MR-compatible Environment

Magnetic Resonance Imaging (MRI) is one of the major approaches of medical imaging, because it is non-invasive and provides high imaging contrast. With the continuous improvement of MRI, it has significantly upgraded the level of our health care. MRI now has been widely used in brain studies, cognitive neuroscience and clinical research.Because the acquisition time of imaging data when running a MRI sequence is typically lengthy and a patient must remain motionless during the procedure of acquisition, motion artifacts are inevitable. Consequently, such motion artifacts will impair the quality of the imaging data, and thereby bias a doctor’s diagnosis. The imaging data thus acquired therefore have to be corrected by employing certain post-processing methods to remove the artifacts in the raw data so that the data can be recovered. Under some circumstances that frequently happen (e.g. subjects move out of the Field-of-View (FOV) or heavy head motion appears during the scanning session), however, the post-processing technique may not be able to completely recover the images.Functional magnetic resonance imaging (fMRI) is widely used in cognitive neuroscience and psychological research. For example, positioning functional brain cortex. Studying the mechanism of creative thinking in humans is one of the hottest topics in fMRI studies, which is actually a subject received intensive attention across many different disciplines. In the field of intelligent computer-aided design (iCAD), the framework of "multi-source analog generation design" is a computable model that can simulate the process of human’s creative thinking on a computer. While nobody has introduced this concept in fMRI studies, we propose for the first time study human creative thinking in our work, using this analogue generation model.The work presented in this study covers the two parts that discussed above.Part I reports our development of a video-based tracking system for correcting motion on-the-fly during MRI acquisition, by reconstructing the spatial coordinates of the target marks in3D space that firmly attached to the subject being imaged, then updating the motion parameters that identify the subjects’ spatial posture to the MR scanner system in real-time, and finally modifying the scanning parameters of the corresponding MR pulse sequence to achieve motion- free imaging. The study has shown that the optical tracking system can successfully correct motion artifacts, and has the potential to completely remove motion artifacts.Part Ⅱ reports our work of a system called "Three-Source Analog System for Face Generation" for fMRI studies of human creative thinking. Because traditional experimental platform is unable to meet the demand for our programming, we have developed a magnetic resonance compatible platform, which can synchronize scanning with the corresponding experimental tasks, and simultaneously collect and record the subject’s reaction. The study has shown that creative thinking is the result of a collaboration of multiple brain regions.