If Pavlov Played the Slots, He wouldn't Have Needed a Dog

12 April 2004

By Alan Krigman

Conditioning is a central training principle of behavioral psychology. Nearly everybody knows of the experiments by Ivan Pavlov in the early 1900s. Pavlov started by ringing a bell and presenting food simultaneously. When he stopped offering the food, the dogs still salivated at the sound of the bell. Later, to keep the dogs responding to the bell, he reinforced the behavior by accompanying it with food at random, but frequently enough that the stimulus was not futile too often. B F Skinner extended this work during the 1930s using conditioning to train animals such as pigeons and rats to perform various tasks.

Tom Creed, a psychology professor at the College of St Benedict at St John's University, says that slot machines utilize similar conditioning processes to produce player behavior characteristics desired by the casinos. Interestingly, slot machine developers didn't expressly build these features into the apparatus. Rather, the machines are successful because they happen to include them.

According to Professor Creed, the desired behavior is for patrons to be attracted to the machines, to gamble once attracted, and to continue playing for extended periods. More, this behavior must be maintained despite the negative influence of losses. A device "that can succeed under these conditions is indeed a model of operant conditioning at work," he states. Further, "the slot machine's nickname, 'one-armed bandit,' is indicative of the control it exerts over the player but is only half accurate -- it does take money from its victim, but must do so by enticement rather than force. 'One-armed hustler' would be more accurate."

Attracting solid citizens appears to be a matter of equipment design, from general appearance and sound to displays of payouts. This may help explain the current popularity of "themed" slots. Differences between Little Bo Peep and Count Dracula games may be nothing more than images on the screen or graphics on the faceplate; however, individuals may show preferences for one or the other, as well as a proclivity to investigate something new particularly when they can identify with it.

The most powerful feature of the slots for encouraging desired behavior, Professor Creed believes, is the reinforcement function. Payouts, which comprise the primary fortifying element, occur at unpredictable intervals and are of variable sizes. Play is initiated by the "possibility of winning big," he says. Gamblers "are not dreaming about small, relatively frequent reinforcement. The lure is hitting the jackpot." But, once begun, interest is kept up by the variable interval reinforcement of the modest returns. "This 'schedule-induced behavior' is so potent," he adds, "it is often regarded as an addiction."

Numerous small wins are augmented in maintaining behavior by secondary conditioning mechanisms, especially during periods when little or no return is obtained. In slot machines, the most important of these is the relative frequency at which players think they "almost" win. "Getting two out of three jackpot bars on a payline is exciting [and] the player has been reinforced at no cost to the [casino]." High-value symbols visible on the display but not together on a payline are alternate conditional reinforcements that don't cost the bosses a cent. A conditioned stimulus effect, chiefly resulting from the bells, whistles, and flashing lights associated with winners on nearby machines, is an additional obvious means of secondary reinforcement. Cashback and slot clubs, while not inherent machine features considered by Professor Creed, serve comparable reinforcement roles.

Superstition is yet another conditioning principle intimately associated with slot machines. Prominent among these, Professor Creed asserts, is switching among machines. "Occasionally, switching is followed by reinforcement. When this happens, not only is slot playing reinforced, but so is switching."

This doesn't necessarily equate slot players to rats who find their way through mazes when there's no cheese at the end. Not necessarily, anyway. For, as the poet Sumner A Ingmark, wrote: