It's not just basketball players and gamblers who fall prey to believing in "lucky streaks" -- monkeys do, too. When scientists trained three rhesus monkeys to play a computer game, the primates acted as if they always made winning choices, even though wins came at random. The monkeys basically made choices as if they were on a roll in a casino, laying down bets.
The scientists had monkeys play thousands of rounds of a simple game, to figure out if monkeys would succumb to the "hot hand phenomenon." (When basketball players mistakenly feel more likely to score after sinking a shot, that's the hot hand phenomenon.) "Luckily, monkeys love to gamble," states Tommy Blanchard, a cognition expert in at the University of Rochester in New York and an author of the new study in the Journal of Experimental Psychology: Animal Learning and Cognition.
To win juice rewards, the monkeys had to correctly guess which side of the screen would show a colored rectangle. There were two types of scenarios in the game: a pattern or a random sequence. The rhesus monkeys quickly mastered the pattern. But when games became random, the monkeys continued to guess as if they were playing in a pattern scenario, too.