The TBI Research Unit at McGill studies the consequences of traumatic brain injuries on visual perception and visual processing. After psychophysic experiments evaluating potential changes, that can remain unnoticed in everyday life, we compare these results with the average population who never had TBI. We postulate that the inhibition and excitation fragile balance in the brain is threatened and possibly modified by a TBI. We thus work with different technologies to illustrate the shift occurring between these two processes. We work in close collaboration with the Neurocircuit clinic.