Traumatic brain injuries and damage are major causes of death and disability. Whereas recent experimental evidence has uncovered mechanical phenomena accompanying the neural activity, the mechanism by which mechanical impact affects neuronal impairment remains unclear. We propose a 3D model of a nerve bundle to understand the electrophysiological changes due to trauma. Here, the electrical and mechanical phenomena are simulated simultaneously by using electro-thermal equivalences in the finite element software Abaqus CAE 6.13-3. This model provides a unique framework which combines a real-time fully coupled electro-mechanical, modulated threshold for spiking activation and damage as a function of strain and strain rate. Results show the alteration of electrostriction and neural activity due to damage as observed in experiments. One of the key findings is the distribution of residual stresses and strains at the membrane of each fibre due to mechanically-induced electrophysiological impairments.