A slot is a narrow opening in a machine or container into which one can insert something, for example a coin. Alternatively, the term can refer to the time a person has reserved to be available for an event or appointment. For example, a person might be told to come at 3 PM to an interview, or a doctor might be able to see a patient in a certain time slot during the day.

A common theory of why near-miss feedback reinforces continued play in gambling games is that the visual aspect of a near-miss approximates a win. For example, obtaining “cherry-cherry-lemon” on a slot machine might seem more like a winning combination than “cherry-cherry-cherry.” However, experimental evidence to support this theory is mixed and the mechanisms underlying near-miss feedback remain unclear.

In one experiment, Strickland and Grote manipulated the frequency of winning symbols on a slot machine and found that players in groups where near misses occurred more frequently opted to continue playing after the presentation of a series of losses. Despite the finding, several subsequent experimental assessments have failed to replicate this result. In addition, a self-report administered after the extinction phase of these experiments reported that participants did not find that a greater frequency of near misses was associated with a greater likelihood to persist in their gambling response. This may be because a large proportion of the gambling response is driven by psychological rather than reinforcement processes.