Speaker
Description
Since its discovery by physicists in the early 1990s, functional MRI (fMRI), based on the Blood Oxygenation Level-Dependent or “BOLD” signal, has revolutionized our ability to non-invasively map the functional organization of the brain at high spatial and temporal resolution. The BOLD signal, however, can be challenging to interpret because it is an indirect measure of brain activity that relies on coordinated changes in brain physiology (blood flow, blood volume, and metabolism), which can be altered in neurological and psychiatric disorders, and over the healthy lifespan. This shortcoming, amongst others, has impeded the more widespread adoption of BOLD fMRI in the neurosciences and clinically. To better interpret the BOLD signal, biophysical models that link the BOLD signal to underlying physiology have been developed. In this talk, I will summarize recent developments and my lab's work developing and applying such models using numerical simulations of the vasculature and analytical descriptions of the BOLD signal. These have allowed us to extract detailed physiological information, which is quantitative and interpretable, from functional MRI, thereby providing valuable insights into healthy and diseased brain function.