Thanks gwern for returning to the discussion, cheers.

This is just missing the point. The mind is what the brain does. If a teenager chooses the higher reward and glances away, then by definition the areas involved in inhibition etc aren't going to be as busy! If they were equally busy in both the glancers and non-glancers, no one would be discussing them in the first place!

Perhaps I am missing the point. I reason that one point is that if the areas involved in inhibition aren't busy, then the person isn't estimating risk, in context, they are instead being overconfident in their decision making, they've not judged the situation, instead acting in impulse.

Unfortunately, we pay with death for both action and inaction. Destroying my own argument indeed. If you seriously mean that, then you must mean that no risk should ever be taken, which is not a position many will sympathize with.

Well no actually, I do seriously believe that you've destroyed your own argument and I don't mean that no risk should be ever taken, instead I mean that when the risk is death of oneself or others then the risk is so high as to outweigh most, if not all rewards.

Nothing inescapable about it. What we have is a worthless anecdote you insist on supporting your position, extremely strong evidence against underestimation of risk, brain-imaging results you do not understand, none of which forces the conclusion of overconfidence as opposed to teens intrinsically having higher rewards just as they intrinsically oversleep and all the over changes that go with puberty and being young adults.

The evidence isn't extremely strong against underestimation of risk, Dobbs wrote about growing from teenager to adult... "When this development proceeds normally, we get better at balancing impulse, desire, goals, self-interest, rules, ethics, and even altruism, generating behavior that is more complex and, sometimes at least, more sensible. But at times, and especially at first, the brain does this work clumsily. It's hard to get all those new cogs to mesh."

If one gets better at balancing those things during development, ie. growing up, that reveals one has a lack in balancing those things, which are to do with judgement - and poor judgement is one form of overconfidence. http://en.wikipedia.org/wiki/Overconfidence_effect

Dobbs goes on to write, "This let the adults use a variety of brain resources and better resist temptation, while the teens used those areas less often and more readily gave in to the impulse to look at the flickering light..." this reveals that teens give in to impulse, which is about lacking judgement which goes to them being overconfident.

Dobbs continues "If offered an extra reward, however, teens showed they could push those executive regions to work harder, improving their scores."

This draws out a reason why they underestimate risk - because if the reward isn't "extra" or perceived as higher to the teen, then they likely won't push those executive regions to work harder, as is revealed in the articles previous paragraph, which I haven't quoted.

Dobbs continues "Add stakes that the teen cares about, however, and the situation changes. In this case Steinberg added friends: When he brought a teen's friends into the room to watch, the teen would take twice as many risks, trying to gun it through lights he'd stopped for before. The adults, meanwhile, drove no differently with a friend watching."

This can actually be interpreted either way, Steinberg chooses a higher reward, whilst one can just as reasonably choose an underestimation of risk – a rationale for which is alluded to in article is that social feelings/thoughts are more sensitive for the teenagers, hence the brain is more focussed on social cognition than risk estimation (as the risk estimation processes require more effort), hence less brain cycles on risk estimation – hence risk underestimation.

If I may use a real world scenario based upon the research and one that does happen, i.e. not fictional. When a teenagers friends are brought into their car, the teen would take twice (or some other >1 multiplier) as many risks, trying to gun it through lights he'd stopped at before. (rephrasing dobbs, reasonably I believe) It's known that some teenage passengers and drivers encourage or engage in risky driving for the thrill, that includes the social aspect of a shared thrill - in this situation the risk has also multiplied for now the death of passengers should be taken into account, whilst the reward has also increased. Might be zero sum, don't know, more research needed, but it’s clear that both reward and risk have increased due to the presence of others.

Now I hope that all you guys can see, this isn't a case of me being some tired old man who doesn't understand the joys of risk taking and thrill seeking. One should not forget that whilst I may be a somewhat respectable sober adult, I have already been through the teenage years under discussion and hence am able to recall those feelings that have been presented as if I am incapable of relating to. On the other hand a thrill seeking teenager is likely to be less aware of what it is to be a respectable sober adult, having never been one. In short I've been both a thrill seeking teenager, a thrill seeking adult and also a respectable sober adult. I do see both sides of this discussion.