Pigeons and humans don’t have much in common until it comes to problem gambling
A pigeon walks into a casino and steps up to a slot machine. Is it likely to gamble? I wouldn’t bet against it.
As it turns out, pigeons will take a chance on a very low probability large reward (gambling) over a sure thing – a more optimal small reward (the equivalent of not gambling).
Specifically, the pigeon can choose between two white lights. If it pecks one light it gets a yellow light that signals 3 pellets of food every time (the non-gamble). Or it can take a chance and peck the other white light. If it does, 20 percent of the time it gets a green light signaling the ‘jackpot,’ 10 pellets of food. But 80 percent of the time it gets a red light signaling it loses (no food).
Although the gamble gets it an average of only 2 pellets (20 percent of 10), the pigeon has a strong preference for the chance to get 10 pellets.
Biologists would argue that animals have evolved to be “optimal foragers.” They have evolved to evaluate choices and detect the better food alternative. But they don’t always do that.
Why should we humans care? Supposedly, humans gamble for its entertainment value. Observing the arrays of slot machines at casinos and racetracks, often populated by (dare I say) addicted gamblers, does not suggest that those people are having fun.
Do pigeons gamble ”for the fun of it.” Pigeons are known to be impulsive animals. If you offer them a choice between 1 pellet of food now or 5 pellets of food in 10 seconds, they seem to lack self-control. They will choose the smaller sooner reward. Coincidentally, problem gamblers also tend to show a lack of self-control and, relative to non-gamblers, they tend to go for smaller sooner rewards.
As it turns out, for pigeons the probability of losing has little effect on their gambling — and it doesn’t appear to affect problem gamblers either. Consider the lottery. Judging by the advertised value of winning the lottery (on billboards and TV news shows), it is not the probability of winning but the expected value of a win that counts. Just as with humans, the low probability of winning doesn’t appear to affect pigeons.
Pigeons will even gamble if they have a choice between a 50 percent chance of a signal for food and a 100 percent chance of a signal for food. It is as if they don’t expect to win - so when they do win, the value of winning is greater than the actual reward itself. And that’s what keeps them gambling. Humans and pigeons differ in many ways, however, the drive to get that surge of adrenaline that often comes with winning when you don’t actually expect to win is likely to be similar in many species.
Paradoxically, human gamblers are often those who can least afford to gamble. Interestingly, hungry pigeons tend to gamble more than less hungry pigeons. The hungry pigeons need the food more, but by gambling they get less of it.
Most interestingly, if we give the pigeons experience in an enriched environment, where they can fly and interact with other pigeons, they are less likely to gamble in these gambling experiments. This finding may have important implications for the treatment of problem gamblers.
It may be that the excitement that problem gamblers get from winning, or even the thought of winning, can be replaced with certain activities (e.g., playing sports or camping). And those activities would not only replace the devastating economic and social consequences of problem gambling but they might also have the added effect of contributing to the health of the former gambler.
Thomas Zentall is a Research Professor of Psychology at the University of Kentucky.