The effect of viscoelastic brain on the dynamic characteristics of the human skull-brain system

In this paper, we present a solution to the problem of free vibrations of the human head system taking into account the dissipative behaviour of the brain. The mathematical model is based on the three-dimensional theory of viscoelasticity and the representation of the displacement field in terms of the Navier eigenvectors. The frequency equation is solved numerically and the results for eigenfrequencies and damping coefficients are presented for various geometrical and physical parameters of the system. The results obtained are in excellent agreement with the measured eigenfrequencies, and the predicted damping coefficients are within the order of magnitude of the measured ones. From the proposed analysis we have obtained the information that the role of the viscoelastic neck as well as the viscoelastic properties of the skull-brain system have to be simultaneously taken into account in the study of the frequency spectrum of the human head. The analysis of the realistic model is under preparation.