Slots (physical and online) are the most popular form of casino gambling in the United States. While most people gamble for fun and as a harmless social activity, a small subset of players can experience serious gambling problems that include financial debt, emotional distress, interpersonal difficulties, professional struggles, and involvement in illegal activities to support their gambling behavior.

To better understand the appeal of slots, we developed two psychophysiological measures of reward reactivity that gauge how much players enjoy playing them. Unlike other psychophysiological measures that use cumbersome electrodes and wires to record brain activity, our instruments are unobtrusive and designed to capture only the most natural aspect of a player’s game-play: pressing the spin button. Specifically, we fixed a force transducer underneath each spin button of three separate slots simulators, housed in slot machine cabinets, and recorded the amount of pressure required to depress the button. Each transducer produced a single volt signal that was recorded by an AD Instruments PowerLabs device, and saved into the Labchart software.

Our results showed that both of our measures of in-game reward reactivity were positively related to retrospective ratings of positive affect, suggesting that the two measurements tap into distinct aspects of the enjoyment of slots. The findings further supported the validity of our approach, and underscore the importance of measuring both types of satisfaction in a game. Accepting that winning at slot games is largely a matter of chance, while controlling what you can control (such as setting win and loss limits), will help maximize your chances of enjoying the game to its fullest extent.