There’s some debate in poker about whether fixing your opponent with a steely gaze has any real value in terms of making you a more successful player. If we’re to believe fictional portrayals of poker games (think Bond vs Le Chiffre in Casino Royale), a stare-down with a rival will either lead to the hero spotting a vital ‘tell’, which allows them to win a vast quantity of cash (and to triumph over evil!), or intimidate their foe into folding their (usually winning) hand.

However, watching pro poker players on TV shows us something very different: many of them are reluctant to engage in a staring match, preferring not to hold the gaze of an opponent for fear of giving something away.