There can be damage either to the ear itself or to the central auditory pathways that process the information conveyed by the ears. People who sustain head injury are susceptible to hearing loss or tinnitus, either temporary or permanent. Contact sports like football (U.S. NFL), hockey and cricket have a notable incidence of head injuries (concussions). In one survey of retired NFL players, all of whom reported one or more concussions during their playing careers, 25% had hearing loss and 50% had tinnitus.