A slot is a narrow opening, groove or channel in something, often used for receiving objects. In a computer, a slot may refer to an expansion slot, such as an ISA or PCI slot that allows for the insertion of various cards that give the machine additional functionality. A slot may also refer to a position on a motherboard that allows for the installation of various add-ons, such as sound cards and video cards.

The allure of slot machines is due to a number of factors. One is the rapid feedback – unlike other gambling forms, players know immediately whether they have won or lost. Additionally, monetary gains are accompanied by high-fidelity attention-grabbing music and amusing animations (Griffiths & Parke, 2005; Haas & Edworthy, 1996). Another factor is the uncertainty of winning or losing – slot machines use a variable-ratio reinforcement schedule that makes it impossible for players to anticipate when they will win or lose.

Finally, the allure of slots can be linked to their escapism qualities. For example, as shown in the movie National Lampoon’s Vegas Vacation, Chevy Chase’s character, Clark Griswold, gets caught up in a losing streak that turns into an all-out binge. However, while the majority of gamblers enjoy their slots play without any negative repercussions, a small subset of gamblers can experience severe gambling-related problems that range from debt to professional and interpersonal difficulties.

To understand how slot players perceive the varying dimensions of enjoyment, this study utilizes two new psychophysiological measures of reward reactivity. Unlike other psychophysiological measures that involve cumbersome electrodes and wires, these measures are completely unobtrusive, relying on the natural pressure exerted by the player’s fingers on the spin buttons of three separate slot-machine simulators. The pressure is translated into a volt signal recorded by a force transducer fixed underneath the spin button of each machine.