ELECTROMAGNETIC NEUROIMAGING OF THE AGING BRAIN

血流动力学神经成像方法（PET，fMRI）的时间分辨率较差。 血流变化太慢（几秒钟），无法跟踪动态认知过程。这种局限性在衰老的神经心理学研究中很重要。即使在抽象认知、记忆或灵活性的测量中没有显示出正常衰老的影响，老年人也总是比年轻人慢。此外，评估阿尔茨海默氏痴呆症的早期智力下降将受益于神经成像技术，以跟踪特定记忆功能的过早减缓。我们建议开发一种先进的密集传感器阵列脑电图（EEG）系统，该系统针对与全头脑磁图（MEG）系统的集成进行了优化。我们介绍了一种256通道传感器网络，该网络通过碳纤维电极和生理放大器实现低磁噪声，该放大器专为高头皮阻抗传感器和低磁干扰而设计。最重要的是，我们提出了一个完整的电磁信号分析策略，其中电场和磁场的不同优势结合在一个交钥匙软件包中。虽然所提出的电磁神经成像系统最初将出售给研究实验室，但在理解老年大脑中心理操作的时间过程变化方面的进展将具有重要的临床应用。拟议的商业应用：通过以毫秒级精度跟踪神经生理学减慢，密集阵列MEG/EEG可以优化我们对老年人神经系统疾病的理解，从而在治疗仍然有用时准确评估痴呆疾病。

Hemodynamic neuroimaging methods (PET, fMRI) have poor temporal resolution. Blood flow changes too slowly (over several sec6nds) to track dynamic cognitive processes. This limitation is important in neuropsychological studies of aging. Even when measures of abstract cognition, memory, or flexibility show no effects of normal aging, the older person is consistently found to be slower than the young person. Furthermore, assessing the early mental decline of Alzheimer's Dementia would benefit from a neuroimaging technology to track the premature slowing of specific memory functions. We propose to develop an advanced dense sensor array electroencephalographic (EEG) system that is optimized for integration with whole-head magnetoencephalographic (MEG) systems. We introduce a 256-channel sensor net that achieves low magnetic noise with carbon-fiber electrodes and a physiological amplifier that is engineered for high scalp impedance sensors and low magnetic interference. Most importantly, we propose a fully electromagnetic signal analytic strategy, in which the differing advantages of electrical and magnetic fields are combined within a single turnkey software package. Although the proposed electromagnetic neuroimaging system would be sold initially to research laboratories, advances in understanding the changes in the time course of mental operations in the aged brain will have significant clinical applications. PROPOSED COMMERCIAL APPLICATIONS: By tracking neurophysiological slowing with rnillisecond precision, dense array MEG/EEG could optimize our understanding of neurological disorders of the aged, leading to accurate assessment of dementing illness when treatment is still useful.