Researchers say 96% of former NFL players who donated their brains to science after death tested positive for a brain disease linked to concussions. CNN’s Sanjay Gupta explains.
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Win a Trip to CMA Fest 2026 in Nashville
Listen for your chance to win a trip to CMA Fest 2026 in Nashville! Catch the TV Special on June 26th at 8/7c on ABC and streaming next day on Hulu.