【摘要】 实时功能磁共振成像通过技术手段将数据分析所需的时间缩短到可与数据采集时间相比拟的程度,从而能在实验进程中将大脑皮层活动情况即刻反馈给受试者,构成一个闭合的神经反馈回路.近年来随着数据采集技术与图像重建算法的改进以及计算机运算能力的提高,实时功能磁共振成像技术日趋成熟并在诸多方面得到应用.凭借实时功能磁共振成像提供的神经反馈,受试者能够自主调节相关脑区的激活水平,与被调节脑区相关的认知过程或行为也会随之变化,这为认知神经科学提供了一种新的研究范式.实时功能磁共振成像还可以用作具备优良空间分辨率和全脑覆盖性的脑机接口,通过对大脑皮层激活模式的分析对脑状态进行判断和分类,从而实现仅依赖大脑活动的交互方式.另外,实时功能磁共振成像在临床上的潜在应用也得到了广泛关注,它为神经系统或精神类疾病的治疗与康复提供了新的途径,患者有望通过神经反馈调控异常的大脑激活状况从而缓解相应症状.本文旨在对实时功能磁共振成像的概念、关键技术及相关应用进行详细的介绍,并对其面临的问题和发展的前景进行讨论.更多还原

【Abstract】 Real-time functional magnetic resonance imaging(rtfMRI) has made it possible to gain accesses to brain cortex activities immediately in an on-going experiment by analyzing data as fast as they are acquired.The continuously updated hemodynamic results could be used as neruo-feedback to build a closed information loop.Recently improvements in acquisition techniques and processing algorithms along with advances in computational power have facilitated the development of rtfMRI and its applications in neuroscience and clinical therapy.Preliminary evidence suggested that self-regulation of certain brain areas could be achieved by rtfMRI neuro-feedback,resulting in the changes of related cognitive processes or behaviors,which provides a novel paradigm for cognitive neuroscience.rtfMRI can also be used as a brain-computer interface with high spatial resolution and whole brain coverage.Since brain states can be decoded and classified in real time,interactions with the outside could be dependent only on brain activities.In addition,the potential usage of rtfMRI for clinical applications has drawn public attentions.Patients might be able to modulate their abnormal brain activation using neuro-feedback based on rtfMRI,thus it has been suggested as a new tool for the treatment and rehabilitation of neurological or pathological disorders.This article aims to review the core concepts,key techniques and related applications of rtfMRI.Current problems and future directions are also discussed at the end.更多还原