Traumatic brain injury derived from an external source and non-traumatic brain injury derived from either an internal or external source. Traumatic brain injury does not always result in obvious motor impairment. Other hidden symptoms related to cognition and behavior can also occur with traumatic brain injury. The two most common causes of traumatic brain injury are Falls and road traffic accidents (RTA), which includes vehicle collisions, pedestrians being hit by a vehicle, vehicle-cyclist and car-motorcyclist collisions as well as bicycle and motorbike crashes which do not involve another...