Déjà vu is really hard to study because it occurs for a short time, unannounced, only in some people mostly between the ages of 8-25 and has no witnesses or physical evidence other than the person announcement. That is why there is little firm research and no explanations. Déjà vu studies must depend on personal descriptions and recollection for data. Now, these studies show that the brain function, especially the vision system, and this phenomenon are related. That is about a disconnection! Watch the video to find out.