Global Impact of Aging on the Hemodynamic Response Function in the Gray Matter of Human Cerebral Cortex.

ABSTRACT: In functional magnetic resonance imaging, the hemodynamic response function (HRF) is a stereotypical response to local changes in cerebral hemodynamics and oxygen metabolism due to briefly (< 4 s) evoked neural activity. Accordingly, the HRF is often used as an impulse response with the assumption of linearity in data analysis. In cognitive aging studies, it has been very common to interpret differences in brain activation as age-related changes in neural activity. Contrary to this assumption, however, evidence has accrued that normal aging may also significantly affect the vasculature, thereby affecting cerebral hemodynamics and metabolism, confounding interpretation of fMRI cognitive aging studies. In this study, use was made of a multisensory task to evoke the HRF in ~87% of cerebral co

SUBMITTER: Fesharaki NJ 

PROVIDER: S-EPMC11653092 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature