Former New Zealand Māori All Blacks, Highlanders and Tasman flanker Shane Christie has died, aged 39.

Christie was forced to retire from professional rugby in 2017 after a string of concussions - and since became a spoken advocate on the subject, offering to donate his brain to help contribute to the research.

D'Arcy spoke with professor of neuroscience at AUT, Doug King, about Christie's death - as well as the research on the impact of head injuries.

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