NASCAR Hall of Famer Darrell Waltrip's family revealed over the weekend he has been diagnosed with frontotemporal degeneration complicated by possible chronic traumatic encephalopathy. ↧ What to know about frontotemporal degeneration after NASCAR Hall of... NASCAR Hall of Famer Darrell Waltrip's family revealed he has been diagnosed with frontotemporal degeneration. Here's what to know about the condition.