This article shows a solution for the computation of deformable tissues displacements in the brain shift problem in neurosurgery. In this type of surgery, the brain moves and deforms, changing the pre-surgical reference the surgeon had before the intervention. Among the causes of brain shift are the effect of gravity, loss of cerebrospinal fluid as a consequence of the resection practiced, the effect of the drugs supplied, among others. This document refers to the physical model of this displacement to later simulate them in multiphysics software. A phantom test was constructed by means of hydrogels, imitating the porcine brain tissue, which is subjected to compression along the z-axis. The results show that the simulation proposed reproduces the behaviour of the real phantom with a high level of accuracy. The application developed may serve in the future to reproduce the total behaviours of the brain and thus obtain a better calculation of the brain shift.