Probability of Winning At Rock-Paper-Scissors is Higher With Eyes Closed thus establishing the deep-seated Urge To mimic

In a new study published in the Proceedings of the Royal Society B earlier this week, researchers at the University College London (UCL) revealed that the human urge to mimic others is so deep-seated that our probability of winning the playground hand game of Rock-Paper-Scissors is higher with eyes shut than with eyes open.

Before you try to figure out the odds of winning Rock-Paper-Scissors with eyes shut, try thinking about, what are the odds with your eyes open?

All over the world, the one-handed game of Rock-Paper-Scissors is an all time playground favorite. Rock (closed fist), Paper (flat hand), or Scissors (fist with index and middle finger open like scissors) – these are one of three possible single hand gestures that you and your opponent have to show at the same time.
A winner is declared when, Rock beats Scissors (because it can crush them), Paper beats Rock (because it can wrap around it), and Scissors beats paper (because they can cut it). The game ends in a draw when both you and your opponent show the same hand gestures.

There are nine probable patterns comprising: three of win-lose, three of lose-win, and three of draw-draw. Consequently, if both opponents “show their hand” precisely at the same time, the expected probability of the game ending in a draw is one in three.

These were the observations made by researchers when both players were blindfolded. When one of the players did not wear a blindfold while the opponent did, the probability of a draw (with eyes open) increased! The players could not resist mimicking the hand gestures of their blindfolded opponent. This was regardless of the fact that winning the game had a financial incentive to it.

For the study, a total of 45 volunteers were recruited by Lead author Richard Cook, from the UCL Department of Cognitive, Perceptual and Brain Science, and colleagues. The players were required to play the game under one of two conditions: with and without blindfolds.

Both players were blindfolded under the first condition while only one was blindfolded in the other. As an incentive to avoid draws, players who won majority of the games out of a total of 60 in each match were promised a financial reward.

Cook and colleagues observed that under the blind-blind condition, the number of games ending in a draw was one in three which is exactly what one might expect by chance. However, under the blind-sighted condition, the number of games ending in a draw was significantly higher than a third: even when it was not in their interest to do so, the hand gestures of the blindfolded opponent were being copied by the sighted player.

“From the moment we’re born, we are frequently exposed to situations where performing an action accurately predicts seeing the same action, or vice versa. Parents seemingly can’t help but imitate the facial expressions of their newborns – smiling, sticking their tongues out and so on,” Cook told the press.

He added that the impulse to imitate is triggered by such experiences “to become so ingrained it is often subconscious, for example when one person starts tapping their foot in a waiting room it is not uncommon for the whole room to start tapping their feet without thinking.”

If hand gesture responses are “automatic” and not voluntary results of thinking, then in order to make the same action in the other player almost instantaneous, the mere sight of action in one player has to excite the motor “program” in the other.

There is substantial proof to support such responses in what is called the “mirror neuron system.” This system reacts instantly at the sight of an action, thereby introducing a prejudice towards imitation that has to be overcome if one tries to act differently.

Imitative responses occur more rapidly than non-imitative ones and there is enough evidence to support this, said Cook. There have been experiments that have been conducted with reaction times ranging between 200 and 400 milliseconds.

He added that the study shows, such imitative responses can be hard to stop therefore seeming to be almost “automatic.”

The study was funded by the Economic and Social Research Council.

“Automatic imitation in a strategic context: players of rock-paper-scissors imitate opponents’ gestures.”
Richard Cook, Geoffrey Bird, Gabriele Lünser, Steffen Huck, Cecilia Heyes.
Proc. R. Soc. B, Published online before print 20 July 2011
DOI:10.1098/rspb.2011.1024