Will life extension increase risk aversion?

Scientist Tom Johnson says that humans someday might live to 350 years old. Aubrey De Grey argues that as our lifespans become longer, we might stop taking high-speed automobile trips. Why risk losing so much, and after all, what would the hurry be?

FuturePundit suggests that perhaps our level of risk-taking behavior is regulated by our biology and hormonal systems. So if driving a car doesn't "feel too risky" now, living to 350 won't change this, perhaps we were never making an intertemporal calculation in the first place. Furthermore, it is young males who take the most risks, and they have large numbers of years left to lose. So giving us more years might not change our behavior that much. FuturePundit then wonders how drugs and neuroscience engineering might change this conclusion. What if you could take drugs that would make you more averse to risky behavior? Might you then, sitting alone in your room, ponder your remaining 320 years and decide to clutch on to them?