The presenter told Top Gear Magazine that reading about Formula 1 driver Felipe Massa's recent accident reminded him of his own experience.
Hammond said: "I damaged the front of my brain in my crash in 2006 and the thought of someone else having to set off on the lengthy journey to recovery from such an injury was a glum one.
"But every time I read that Massa hopes to return to racing in F1 soon after sustaining that head injury, I'll admit that my shoulders slump a bit. I know that for me, three years later, the process is still ongoing."
Hammond said: "I damaged the front of my brain in my crash in 2006 and the thought of someone else having to set off on the lengthy journey to recovery from such an injury was a glum one.
"But every time I read that Massa hopes to return to racing in F1 soon after sustaining that head injury, I'll admit that my shoulders slump a bit. I know that for me, three years later, the process is still ongoing."
Massa suffered a fractured skull when he was hit by a spring from another vehicle during qualifying for the Hungarian Grand Prix in July.
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