School of Behavioral and Brain Sciences, Center for Brain Health, University of Texas at Dallas, Richardson, TX, USA.
School of Medicine, Department of Radiology, Johns Hopkins University, Baltimore, MD, USA.
Psychophysiology. 2021 Jul;58(7):e13845. doi: 10.1111/psyp.13845. Epub 2021 Jun 11.
Most studies examining neurocognitive aging are based on the blood-oxygen level-dependent signal obtained during functional magnetic resonance imaging (fMRI). The physiological basis of this signal is neural-vascular coupling, the process by which neurons signal cerebrovasculature to dilate in response to an increase in active neural metabolism due to stimulation. These fMRI studies of aging rely on the hemodynamic equivalence assumption that this process is not disrupted by physiologic deterioration associated with aging. Studies of neural-vascular coupling challenge this assumption and show that neural-vascular coupling is closely related to cognition. In this review, we put forward a theory of processing speed decline in aging and how it is related to age-related neural-vascular coupling changes based on the results of studies elucidating the relationships between cognition, cerebrovascular dynamics, and aging.
大多数研究神经认知老化的研究都是基于在功能磁共振成像(fMRI)期间获得的血氧水平依赖信号。该信号的生理基础是神经血管耦合，即神经元通过信号传递到脑血管，以响应由于刺激导致的活跃神经代谢的增加而扩张的过程。这些关于衰老的 fMRI 研究依赖于血流动力学等效性假设，即该过程不会因与衰老相关的生理恶化而受到干扰。神经血管耦合的研究挑战了这一假设，并表明神经血管耦合与认知密切相关。在这篇综述中，我们根据阐明认知、脑血管动力学和衰老之间关系的研究结果，提出了一个关于衰老过程中处理速度下降的理论，以及它与与年龄相关的神经血管耦合变化的关系。
