Football (soccer) is the only sport, where players purposefully use the head to accelerate the ball. Since the publications of the Dutch research group of J.T. Matser short- and long-term consequences of playing football respectively the impact of headers on brain structure and function have been debated vividly. Recent meta-analysis show that results to date are inconclusive, thus a more thorough understanding of the true risk of headers is essential to estimate the risk of playing football in its current form. Therefore, the main objective of the study is to evaluate, if and how heading in professional football players alters functional and structural brain networks. Secondary objectives are to investigate, if and how heading in professional football players alters neuropsychological performance as well as vestibular and ocular motor functions.