A narrow depression, perforation or aperture, especially one for the reception of something fitting or sliding into it. (Linguistics) The position within a construction or grammatical construct into which any of a number of possible morphemes or morpheme sequences may fit. The position is assigned according to a schedule or sequence, such as a time slot on a broadcasting schedule.

In the casino, slot machines are games of chance in which symbols line up on the reels to trigger a payout, based on a paytable and machine settings. Whether they’re classic three-reel games or more sophisticated multiline machines, slots operate using the same fundamental technology. The differences in their appearance, features and payouts lie in the algorithms used by the individual manufacturers to determine where the symbols will land on each spin.

The allure of the slot machine has long been a subject of interest and research. While the vast majority of gamblers experience recreational gambling and play responsibly, a small subset of players can experience severe gambling problems, including financial difficulties, personal distress, interpersonal difficulties, work-related difficulties, and involvement in criminal activities.

Dixon et al. (2019) report two new measures of reward reactivity that gauge how much players enjoy playing slots. Unlike other psychophysiological measures that use cumbersome electrodes or wires that may reduce ecological validity and inhibit flow, these new measures of enjoyment involve simple computer software that asks players to play their favorite single- or multiline slot machine as they would on the casino floor. The new measures are associated with greater unique positive affect variance in a multiple regression framework than the existing 14 item SPA questionnaire, and both measure reward reactivity independently of dark flow.