Why does the gunslinger who draws first always get shot?

i-0625e965d2fa47fcbb142f4d71b81ac2-Gunslinger.jpgIn Western films, the gunslinger that draws first always gets shot. This seems like a standard Hollywood trope but it diverted the attention of no less a scientist that Niels Bohr, one of history's greatest physicists. Taking time off from solving the structure of the atom, Bohr suggested that it takes more time to initiate a movement than to react to the same movement. Perversely, the second gunslinger wins because they're responding to their opponent's draw.

Now, Andrew Welchman from the University of Birmingham has found that there's something to Bohr's explanation. People do indeed have a "reactive advantage", where they execute a movement about 10% more quickly if they're reacting to an opponent. Of course, ethics committees might frown on scientists duelling with the pistols in the name of discovery, even if the people in question were graduate students. So Welchman designed a laboratory gunfight, played out using buttons rather than guns.

Two opponents faced each other and had to press a series of three buttons as quickly as possible. To begin with, they held a central "home key" with their trigger fingers and they had to wait for a short spell before before starting the round. The point where they were allowed to begin varied from trial to trial and the players weren't told how long it would be. There was no starting pistol or countdown. Either player could start the race but if they went too soon, an alarm would sound to signal a false-start.

These button-mashing duels revealed that, on average, the players completed their sequence 21 milliseconds faster if they reacted than if they initiated. That's an improvement of around 9%, and most of this advantage came at the very beginning, when they pressed the first button. It's an interesting result and like all good scientists, Welchman systematically considered and ruled out several possible explanations for it.

He thought that the three-button task was quite complicated compared to, say, drawing a gun but the reactive advantage remained even when the task was distilled to a single button press. He thought that the expectation of a warning alarm might have slowed the players who started first. But the reactive advantage remained when he repeated the experiment without any warning tone. 

He considered the possibility that the reactors might gain an advantage by being able to model their actions on someone else's. But even if the button order was swapped for one player, or the button array rotated by 90 degrees, still the reactive advantage remained.

Perhaps players were steeling themselves up for one role or the other, or perhaps they planned to win by sacrificing accuracy for speed. But that's not possible - remember that the players didn't know beforehand if they were going to initiate or react. Those roles were only decided once someone moved, which prevents either one from carrying out a pre-planned strategy.

Perhaps some people always chose to react and always did so very quickly? Not so - Welchman found no link between the probability of reacting and the speed of reactive movements. Finally, Welchman wondered if the social aspect of the game was important, so he asked players to duel a computer or a virtual player in another room. And still, they moved faster if they reacted than if they initiated.

Having ruled out these myriad reasons, Welchman thinks that the reactive advantage stems from our use of different brain networks, when moving proactively or reactively. There's plenty of evidence for separate pathways already, and Welchman's idea is that one of these just happens to be slightly faster than the other.

He suggests that the our brain holds in check the actions we plan to carry out, possibly using an area called the supplementary motor area (SMA). Another area - the pre-SMA - lifts this block in order to launch the movement. When we move reactively, another part of the brain - the parietal cortex - lifts the block in a similar but quicker way. From an evolutionary point of view, this all seems reasonable. Reactions are among the most important movements that animals can make, such as escaping from a predator's strike.

So what does this mean for Western gunslingers? Is it always better to draw second? Well, not quite. Welchman also found that the 21 millisecond benefit of reacting quickly was totally overwhelmed by the 200 milliseconds it took to react in the first place. Despite their faster movements, the reactors very rarely beat the initiators. If Greedo hadn't been such a bad shot, Hans would have died (not counting the subsequent editing).

Bohr's idea, it seems, was correct in theory, but wrong in practice. That didn't stop Bohr himself from testing his hypothesis in experimental duels against fellow physicist George Gamow using toy pistols. According to anecdotal reports, Bohr always reacted and he won every duel, but Welchman has the final word on the matter:

"Our data make it unlikely that these victories can be ascribed to the benefits associated with reaction. Rather, they suggest that Bohr was a crack shot, in addition to being a brilliant physicist."

Reference: Welchman et al. 2010. The quick and the dead: when reaction beats intention. Proc Roy Soc B http://dx.doi.org/10.1098/rspb.2009.2123


More like this

Does the amygdala come into play here, as if the reacting player was responding to a threat? Perhaps the sensory information gets sent down the "quick & dirty" pathway. Perhaps I would know this if I hadn't majored in music.

Han shot first.

Yes, Han shot first. Also, it's Han not Hans.

Of course, ethics committees might frown on scientists duelling with the pistols in the name of discovery, even if the people in question were graduate students

Ha! This is why I <3 your blog, humorous lines like that :D

By Christina (not verified) on 02 Feb 2010 #permalink

I'm not sure I'm following this. It takes 200 ms for either reactors or initiators to hit their button sequence, but the reactors are 20 ms faster (rounding out). So, does that mean that once the initiator begins, the reactor is still 180 ms behind? But it doesn't take until the initiator is done before the reactor begins, does it?

It seems like the question is how long it takes the reactor to 'notice' that they've begun to fight. If he notices within the first 20 ms, he'll beat the initiator to the draw.

Directed here by Doctor Cooper. Fascinated by the content, but feel compelled to point out a geek fail.

It's Han, not Hans. =/

It's a beautiful and elegant bit of scientific work ... but I don't buy it. I think if you checked the historical record, you'd find two things to be true:

1) the classic movie-style speeddraw gun duel was extremely rare; and

2) in those speeddraw duels that did take place, there was a tendency for the one who was less confident to draw first, because he hoped that drawing first would give him the advantage. Unfortunately, the lack of confidence would slow him down enough that a better opponent could still outdraw him.

Finally, there's accuracy. Getting off the first shot doesn't help you if the first shot misses. "Fast is fine, but accuracy is final. You have to be slow in a hurry." -- Wyatt Earp.

By wolfwalker (not verified) on 02 Feb 2010 #permalink

Have corrected the Han problem. And I hang my head in shame at forgetting that, yes, Han did shoot first.

I remember reading an article in the children's magazine Look and Learn about thirty-five years ago entitled 'When a fast draw meant a quick death!' which examined this very issue. As far as I recall, the conclusions of the piece were pretty much what wolfwalker has to say above. In the end you can be as fast as fast can be, but it won't do you any good if you don't hit the other guy.

Cool stuff. But the button pressing experiment seems quite a bit different than the gun slinging one, so I rather wonder about generalizing from the former to the latter. Why not replicate the Bohr/Gamow toy gun experiment and then vary who shoots first and who reacts(to control for who's the better shot)?

In the mid 1800's gunfights were seldon as depicted on screen od even in documents written at the time (written by the winners supporters) guns, even the "Colt" were notoriously inaccurate when fired rapidly from the hip and (as is the case with Wyatt Earp - documented) an accurate gun was far better than a fast draw the "Buntline Special" had a much longer barrell than other hand guns and was therefore much more accurate! In Wyatt Earp's case he seldom shot first, always relying on the mind-set of his adversary and the acuracy of his own gun. He actually got "winged" on some occasion(s) and still shot his opponent dead.

By Max Headroom (not verified) on 03 Feb 2010 #permalink

Yes Han shot first but he shot with the gun in his HANS so Han's hans weren't at all handy. Han should have put his hans up!

By The Grim Reaper (not verified) on 03 Feb 2010 #permalink

On a further note, in the actual gunfight, one is reacting to a life-threatening situation instead of a game, which I would imagine has quite different physiological responses and brain activity.

I think the gunslinger angle is more of a nice way of framing an interesting piece of neuroscientific research, rather than the driving force behind it.

Just a quick note about quick draws in action... first, accuracy beats speed, but it is hard to be accurate when you are hit - anywhere. First blood is a big advantage in a duel.

Second, hip shots are truly inaccurate. When using a revolver against a particularly mean slip of paper about fifteen feet away, most shooters can lob a shot onto the target, but only by the sixth shot! Out of ten experienced shooters who tried in our group, one hit the target with the first shot, but then missed the next four.

And I mean to say they hit the target at all, let alone near the bullseye.

No one managed to hip-shoot and hit the target within 6 shots when using a modern auto pistol, in this case a Glock 40 cal. The gun jumps so much that many were unable to get the target in the full 13 shots held by the little Glock.

And finally, like others have said, it all goes out the window when someone would be shooting back!

With all the variables, I think the button pushing method is a better test of reaction time.

A very interesting starting point, but if the question is about _movie_ gunfights, the answer is elsewhere.
I think the reactor in the movies wins because the gunfight is usually at the end, involves the hero, and if the hero goes first he's less of a hero. Drawing second you're defending yourself, and that's the way it should be in the movies.

Wow. What a subject for persons steeped in reality.

The persons who knew by experience are mostly dead, for real. It would be nice to get the take of General Patton who represented the US in pistol shooting at the first modern Olympics, and also some top video gamers, because I suspect that further inspection would show huge individual differences possible.

The reality would be closer to No Country for Old Men, but it's a nice way to get into a subject, something anyone can react to.

NanU, I think you've got the best answer. :-)

I'd add that if Hero is not in the particular duel in question, then it's always Bad Guy vs a redshirt, and it's used to dramatically emphasize what a badass quick-draw Bad Guy is: he can give the other guy the first move and still beat him to the draw.

By wolfwalker (not verified) on 03 Feb 2010 #permalink

You were right first time - it's a law of Hollywood that the initiator of violence cannot win.

However, one question I wish the research had addressed but apparently didn't, is whether the normal sporting technique of visualisation can help the initiator. In other words, if he visualises his opponent moving, then his initiation is effectively a reaction. Indeed, in the conventional scene where the gunslinger practices against a tin can before the big confrontation, he is forced to use visualisation. If doing this routinely shaved 10% off one's reaction times, you'd expect gunslingers to have noticed....

By Ian Kemmish (not verified) on 03 Feb 2010 #permalink

"ethics committees might frown on scientists duelling with the pistols in the name of discovery, even if the people in question were graduate students"

I know a biology prof who says he's not allowed to have undergrads or professors die in field accidents. Grad students are okay though, and mortality for post-docs is actively encouraged.

Hugely interesting; thanks!

All the people who miss the point and go off on the movie gunfight tangent are autistic, by the way. Guys: no one thinks actual gunfights happened like in movies, you need to learn when to not take things seriously.

Most of this movie gunfight stuff is inspired by samurai duels - the situation plays out the same way when one watches a samurai film. The one to draw their sword first almost inevitably gets cut down. There's usually a bit (in eastern or western duels) before the guns/swords come out where the two are just staring at each other, trying to psych the other out. The one that loses his cool first is the first to draw, and the other guy is then able to go for "one cut, one kill".

A patient with Parkinson's, if asked to throw a ball does it with agonizing slowness. bradykinesia . However, if a ball is thrown to him, he can catch it without delay. Startle reflex. Do these responses demonstrate two pathways that are explained in this post? I defer to a neurokinesiologist.