biostudies-literatureEscarcega JDNINDS NIH HHSNational Institutes of Health110259https://www.ebi.ac.uk/biostudies/studies/S-EPMC8055167biostudies-literatureUnknown119Natural modes and frequencies of three-dimensional (3D) deformation of the human brain were identified from in vivo tagged magnetic resonance images (MRI) acquired dynamically during transient mild acceleration of the head. Twenty 3D strain fields, estimated from tagged MRI image volumes in 19 adult subjects, were analyzed using dynamic mode decomposition (DMD). These strain fields represented dynamic, 3D brain deformations during constrained head accelerations, either involving rotation about the vertical axis of the neck or neck extension. DMD results reveal fundamental oscillatory modes of deformation at damped frequencies near 7 Hz (in neck rotation) and 11 Hz (in neck extension). Modes at these frequencies were found consistently among all subjects. These characteristic features of 3D human brain deformation are important for understanding the response of the brain in head impacts and provide valuable quantitative criteria for the evaluation and use of computer models of brain mechanics.Journal of biomechanicsNatural oscillatory modes of 3D deformation of the human brain in vivo.PMC8055167R01 NS055951R56 NS055951U01 NS112120Bayly PVKnutsen AKPham DLEscarcega JDOkamoto RJfalseNatural oscillatory modes of 3D deformation of the human brain in vivo.Natural modes and frequencies of three-dimensional (3D) deformation of the human brain were identified from in vivo tagged magnetic resonance images (MRI) acquired dynamically during transient mild acceleration of the head. Twenty 3D strain fields, estimated from tagged MRI image volumes in 19 adult subjects, were analyzed using dynamic mode decomposition (DMD). These strain fields represented dynamic, 3D brain deformations during constrained head accelerations, either involving rotation about the vertical axis of the neck or neck extension. DMD results reveal fundamental oscillatory modes of deformation at damped frequencies near 7 Hz (in neck rotation) and 11 Hz (in neck extension). Modes at these frequencies were found consistently among all subjects. These characteristic features of 3D human brain deformation are important for understanding the response of the brain in head impacts and provide valuable quantitative criteria for the evaluation and use of computer models of brain mechanics.2021-01-01T00:00:00Z2021 Apr2025-04-26T07:26:21.89Z2025-04-06T12:19:04.553ZS-EPMC80551673361832910.1016/j.jbiomech.2021.110259