Playing cards, used for games and magic, are so familiar, yet we know remarkably little about the way we perceive and think about them. Are some cards more memorable than others? Are some easier to identify? With so much at stake in games like poker, and card magic a staple of family entertainment, it's surprising that no-one has thought to study this before.
Jay Olson, Alym Amlani and Ronald Rensink first tested if some Western playing cards are easier to spot than others. Ninety-six students were shown visual streams of 26 playing cards on a computer, each displayed for a tenth of a second, and they had to say if a certain target card was present in the stream or not. The students were pretty good, achieving an accuracy rate of 80 per cent, but they performed better for some cards than others. For example, they detected the Ace of Spades more easily than any other card, and they detected Aces in general more easily than other cards - probably because of their simple, distinct pattern. Surprisingly, face cards (e.g. Jack, Queen etc) were no easier to spot than number cards, despite being more distinctive. Another curious finding was the students' particular tendency to say the two red sixes (Six of Hearts and Six of Diamonds) were present when they weren't. It's not clear why.
To test the memorability of cards, Olson's team employed a similar methodology. The students saw a stream of seven cards, each displayed for a quarter of a second, and then they were asked to say whether a particular card had been in the stream or not. Again, the Ace of Spades especially, and all Aces to a lesser extent, were more memorable than other cards.
What about likeability? Students were shown pairs of cards and in each case had to say which they preferred. Regards numerical value, the participants liked the highest (10) and lowest (2) cards the most. And they had a tendency to prefer Spades and Hearts over Clubs and Diamonds - maybe because of their rank in games, or their curved shape. Two cards were especially popular - the Ace of Hearts and the King of Hearts. There was also a gender difference in taste. Men tended to prefer higher value cards and women to prefer lower value.