The motion of a viscoelastic material enclosed in a rigid shell which is suddenly rotated about its axis is investigated for three kinds of shells: an infinitely long cylindrical shell, a semi-infinite cylindrical shell terminated at one end by a plane wall, and a spherical shell. With the aid of the analytical solutions of these problems, a model is proposed for brain displacement in the vicinity of the superior sagittal sinus. The material properties of brain matter in terms of the shear modulus, G, and the kinematic viscosity, v, are determined experimentally in transient rotation yielding the values G = 1700 Pa and v = 0.009 m²/sec. Simulation of the brain displacement has been performed using the proposed model and the experimentally found material parameters.