For the downvoters: this recent paper gives a thorough overview on the known effects of repeated head injury, and the currently available evidence: http://ge.tt

For the downvoters: this recent paper gives a thorough overview on the known effects of repeated head injury, and the currently available evidence: http://ge.tt/2Y9BoiC2 http://ge.tt/2Y9BoiC2 In summary, his choice of sport does increase the risk of neurodegenerative disease presenting as dementia in later life, and CTE in particular has a distinct neuropathology that distinguishes it from other presentations at autopsy.