Chronic traumatic brain injury in professional soccer players.

OBJECTIVE: To determine the presence of chronic traumatic brain injury in professional soccer players. METHODS: Fifty-three active professional soccer players from several professional Dutch soccer clubs were compared with a control group of 27 elite noncontact sport athletes. All participants underwent neuropsychological examination. The main outcome measures were neuropsychological tests proven to be sensitive to cognitive changes incurred during contact and collision sports. RESULTS: The professional soccer players exhibited impaired performances in memory, planning, and visuoperceptual processing when compared with control subjects. Among professional soccer players, performance on memory, planning, and visuoperceptual tasks were inversely related to the number of concussions incurred in soccer and the frequency of "heading" the ball. Performance on neuropsychological testing also varied according to field position, with forward and defensive players exhibiting more impairment. CONCLUSION: Participation in professional soccer may affect adversely some aspects of cognitive functioning (i.e., memory, planning, and visuoperceptual processing).