[Close-to-win evaluations are affected by the outcome and delay between stopping the wheels in slot machines]

Distinct structural characteristics of gambling may affect the development of gambling addiction differently. The current study is dealing with the frequency of near-miss outcomes which works like secondary reinforcement and thus may contribute to gambling addiction. Authors of this paper argue that different near miss configurations should specifically alter the experiences of the player and this phenomenon can be proved experimentally Methods: Participants played with a computer-simulated slot machine. They had to evaluate how close they felt to winning in a given round. Evaluation was carried out on a scale in which the "not at all" and "very close" options signified the two endpoints (0 to 100) of the scale. Participants were grouped by delay times in the game. They were randomly assigned to a100ms or a 1000ms delay groups, where longer delay made participants feel themselves closer to a win in case of specific outcomes.

There was a clear pattern of the close-to-win evaluations in the study. The quantitative analysis indicated heterogenity in the evaluations of "near-miss" outcomes. Evidently winning outcomes were rated to be closest to a win. Losing outcomes' ratings on the other hand, were more heterogenous. The first type of "near-miss" configuration caused the feeling of close-to-win significantly more in the participants than the second type of "near-miss" configuration or full loss outcomes. The second type of "near-miss" configuration also significantly elevated the feelings of close-to-win than the full loss outcomes. The delay time in itself did not prove to have a major effect, but the first type of the near-miss configuration influenced the feeling of close-to-win significantly more.

These results stress the importance to reconstruct patients' cognitive distortions during cognitive therapy of gambling addictions.