The near-miss effect in slot-machine gambling

Abstract

Near-miss plays an important role in the development of gambling addictions. In this study, we measured the neural correlates of the process by which near-miss outcomes are evaluated in simplified, static, slot-machine gambling using event-related potentials. Analysis of event-related potentials revealed that the size of FRN (feedback-related negativity) for a near miss is between the full miss and the win. These results suggest that participants distinguish among near misses, full misses, and wins during the early evaluation phase. The subjective value and objective value of outcome were assessed separately to discuss FRN on outcome evaluation. It is suggested that FRN is mediated not only by the objective value of outcomes but also by the subjective value of feedback.

You Do the Math: Coding of Bets and Outcomes in a Gambling Task in the Feedback-Related Negativity and P300 in Healthy Adults

“…While clear wins were associated with a larger P300 than clear losses, thus corroborating previous findings [17], the smallest P300 was found for ambivalent outcomes, for which P300 amplitude differed significantly from both wins and losses. Coding of outcome magnitude in the P300 is thus not linear.…”

“…The exact role of the P300 in feedback processing remains a matter of on-going debate. Previous results indicate that the P300 is larger for positive [9], [10], [17], [30] or negative feedback [31], although the absence of valence effects has also been reported [6], [7]. Generally, the P300 appears to be larger for unexpected compared to expected outcomes, and this effect may be particularly pronounced for positive feedback [14], [30].…”

“…Analyzed ERP components included FRN and P300. Based on visual inspection of the grand-average ERP waveforms, and in following the approach used in a previous study [17], the FRN was defined as mean amplitude in the time window 230 to 330 ms following feedback presentation at electrode FCz. The P300 was defined as mean amplitude in the time window 300 to 550 ms following feedback at electrode Pz.…”

“…In contrast, the P300, a positive centroparietal ERP component starting about 300 ms after onset of a visual stimulus, which is commonly associated with processes of decision making [18], attentional allocation [19] and stimulus evaluation [20], appears to be sensitive to objective outcome valence [21]. Indeed, the P300 has been shown to be larger for wins than for losses, while being similar for losses and near misses [10], [17].…”

“…The size of the FRN in response to near misses, i.e. the experience of coming close to winning, has been shown to be between full miss (direct loss) and win, although – objectively – the near miss outcome does not differ from a full miss [17]. In contrast, the P300, a positive centroparietal ERP component starting about 300 ms after onset of a visual stimulus, which is commonly associated with processes of decision making [18], attentional allocation [19] and stimulus evaluation [20], appears to be sensitive to objective outcome valence [21].…”