Slot is an online video game in which players attempt to match symbols on a screen to win prizes. Traditionally, the machine consisted of a reel that spun when a lever was pulled, but modern slot machines are operated digitally and feature a touchscreen. The games are designed with a variety of themes and include multiple paylines, themed symbols, bonus rounds, and jackpots. Many are also available for free or with a trial period.

While researchers have explored the psychological effects of video games, less attention has been paid to slots. In one study, Dixon et al. used skin conductance responses (SCRs) to measure participants’ arousal during a slots game. Results showed that SCRs increased when a player won, and that the size of the win was associated with greater arousal. The arousal measures were not related to enjoyment ratings, however, suggesting that arousal is not the sole reinforcer of gambling behaviour.

Other research has found that people enjoy slot machines because they release stress and distract from negative aspects of their lives. A recent study used a psychophysiological measure of reward reactivity—which is based on the programming documents of commercially available slots—and found that it was highly correlated with positive affect ratings and inversely correlated with depression scores. Unlike other psychophysiological measures that use cumbersome electrodes and wires to monitor brain activity, this method is easy to administer and provides valuable empirical data on slot play. It also allows researchers to investigate the underlying psychological processes that drive gambling behaviour.