Exercise modulates brain pulsatility: Insights from q-aMRI and MRI-based flow methods

Motivation: The interaction between cranial fluid flow and brain displacement patterns following exercise has not been studied in an MRI context. Quantification of this relationship is now possible with the novel quantitative amplified MRI (q-aMRI) algorithm. Goal(s): Characterization of intracranial fluid dynamics with low-intensity exercise to measure how these correlate. Approach: Cerebral blood flow (CBF), cerebrospinal fluid (CSF) flow, and brain motion were measured at rest and during handgrip exercise to assess relative changes. Results: During exercise, CBF was less pulsatile, CSF flow increased and did not regurgitate, and brain motion reduced. q-aMRI brain motion patterns mimicked CSF flow patterns. Impact: This study demonstrates exercise has a physiological effect on fluid flow and brain displacement. It highlights q-aMRI's potential diagnostic applications, as intracranical dynamics coupling could serve as a potential biomarker of abnormality, especially in intracranial pressure and fluid-related disorders.