Webbe and collaborators tested soccer players in neurocognitive performance such as attention, concentration, and speed of thinking. They compared long-time soccer players to novices, as well as moderate-to-frequent headers to less than moderate headers. In addition, they tested people who had played soccer recently as well as people who hadn't played in some time. The results suggested that more frequent headers are at more risk for brain injury than less frequent headers. As a group, frequent headers performed lower on cognition tests in the week after a game of frequent heading than did other subjects. Also, players with the highest lifetime estimates of heading scored lowest overall on these cognition tests. The results convince Webbe that heading does indeed pose a threat to brain function and that more research needs to be done.