Scottish racing driver Dario Franchitti has spoken about the long-term damage caused by the multiple concussions he sustained during his career.
Franchitti – who competed at the highest level of American single-seater racing between 1997 and 2013 – is one of Britain's most successful professional drivers of recent decades, with four IndyCar titles and three Indianapolis 500 victories to his name.
He was forced to call time on his career behind the wheel following the 2013 IndyCar season, when a heavy crash in Houston left him with multiple injuries, including concussion. He was advised to step away from the sport or risk permanent damage, having already suffered a concussion more than a decade earlier.
The crash that ended Franchitti's career.
Speaking to John Beattie for the BBC, Franchitti admitted that he has no recollection of the period around his first major crash, which occurred during testing ahead of the 2000 season.
"There's a five-week period that's just gone," said Franchitti. "There's maybe tiny snippets that have come back – a minute here, a second there – but otherwise, completely gone."
The 43-year-old went on to discuss his struggles with memory loss, and said that his personality was "completely changed" by his first concussion.
"I was more easy-going beforehand and my concussion made me more serious," he said.
"I brought [this] up to my brother [fellow racing driver Marino] years later. I said, 'I think this [personality change] happened', and he said, 'I never noticed.' But, from the inside, I felt different."
Franchitti believes that he returned to the car too soon in 2000 – he was out for just five weeks, but feels it was two years before he fully recovered – although he credits the focus this required with preventing depression.
He added that his mood was positive after his career-ending accident, saying: "I was so thankful for what I'd [been able] to do. The fact I survived the crash, and what I'd got to do with my life – I was looking at it that way. What's the rest of my life going to bring? What fun can I have? What's the next chapter?"
Returning to concussions, he concluded: "One thing I find fascinating, but scary, is that the damage is cumulative. So you have one concussion, it takes X amount of energy to cause damage. Then the next one takes less energy; and the next one again."
Though his accidents in 2000 and 2013 were particularly severe, Franchitti was involved in several other major crashes during his career, including two terrifying high-speed flips during the 2007 season in Kentucky and Michigan. He now works as an advisor to his former IndyCar team and commentates on the all-electric Formula E series.