Realistic Free-Spins Features Increase Preference for Slot Machines

Post-reinforcement pauses during slot machine gambling are moderated by immersion

The post-reinforcement pause (PRP) is an operant effect in which response latencies increase on trials following the receipt and consumption of reward. Human studies demonstrate analogous effects in electronic gambling machines that utilise random ratio reinforcement schedules. We sought to identify moderators of the human PRP effect, hypothesising that the magnitude of gamblers' PRPs is moderated by the type of reinforcing outcome (genuine wins vs. losses-disguised-as-wins [LDWs] vs. free-spin bonus features) and individuals' level of gambling immersion, a cognitive state linked to problem gambling. Experienced slot machine users (N = 53) played a real slot machine for 20 min. The dependent variable was defined as the time delay in the initiation of each bet ("Spin Initiation Latency"; SIL). Using 80% of trials, a linear model was fit regressing SIL on the independent variables (outcome type, immersion, and outcome-by-immersion interaction), and a larger group of covariates (participant ID, trial number, winnings, etc.) selected using double-robust LASSO-regularised regression. The previously unseen 20% of cases were used to validate the model. Positively reinforcing outcome types (wins, LDWs, bonus spins) showed significantly larger SILs than losses, indicating a PRP effect. Immersion did not predict response latencies, but win-by-immersion and LDW-by-immersion interactions indicated that pauses were greater among more immersed participants. The small number of free-spin bonus features showed similar trends that were not statistically significant. These results indicate that gamblers immersed in play remained sensitive to in-game reinforcement (contrary to a prevailing account), and provide guidance for researchers bridging laboratory research and real-world behaviour.

Do pupillary responses during authentic slot machine use reflect arousal or screen luminance fluctuations? A proof-of-concept study

Modern slot machines are among the more harmful forms of gambling. Psychophysiological measures may provide a window into mental processes that underpin these harms. Here we investigated pupil dilation derived from eye tracking as a means of capturing changes in sympathetic nervous system arousal following outcomes on a real slot machine. We hypothesized that positively reinforcing slot machine outcomes would be associated with increases in arousal, reflected in larger pupil diameter. We further examined the contribution of game luminance fluctuations on pupil diameter. In Experiment 1A, experienced slot machine gamblers (N = 53) played a commercially-available slot machine in a laboratory for 20 minutes while wearing mobile eye tracking glasses. Analyses differentiated loss outcomes, wins, losses-disguised-as-wins, and (free-spin) bonus features. Bonus features were associated with rapid increases in pupil diameter following the onset of outcome-related audiovisual feedback, relative to losses. In Experiment 1B, luminance data were extracted from captured screen videos (derived from Experiment 1A) to characterize on-screen luminance changes that could modulate pupil diameter. Bonus features and wins were associated with pronounced and complex fluctuations in screen luminance (≈50 L and ≈25L, respectively). However, the pupil dilation that was observed to bonus features in Experiment 1A coincided temporally with only negligible changes in screen luminance, providing partial evidence that the pupil dilation to bonus features may be due to arousal. In Experiment 2, 12 participants viewed pairs of stimuli (scrambled slot machine images) at luminance difference thresholds of ≈25L, ≈50L, and ≈100L. Scrambled images presented at luminance differences of ≈25L and greater were sufficient to cause pupillary responses. Overall, pupillometry may detect event-related changes in sympathetic nervous system arousal following gambling outcomes, but researchers must pay careful attention to substantial in-game luminance changes that may confound arousal-based interpretations.

The Effect of Skeuomorphic Digital Interfaces on the Illusion of Control over Gambling Outcomes

The current research focuses on how the use of "skeuomorphs" in digital design interacts with an illusion of control to influence gambling behavior. Skeuomorphism is a design concept in which an aspect of a modern item is made to represent its outdated counterpart, even if this representation serves no functional purpose, such as hands "dealing" cards or horses "racing" on the screen of a digital machine. It is proposed that the inclusion of these non-essential links to physical objects in digital gambling games interacts with a player's illusion of control over the outcome to influence behavior. Shown across a pretest and three experiments, the inclusion of skeuomorphic elements in the design of gambling games, compared to a minimalistic "flat" design, increases amount gambled. Additionally, skeuomorphism and manipulated illusion of control interact to further increase the amount gambled. The manuscript concludes with a discussion on the practical, theoretical, and policy implications of this research.

Free-Spins Spur Gamblers to Quit EGMs Early: An Online EGM Study

Free-spins on slot machines introduce a salient moment of potentially large wins that might influence people to either quit or continue a gambling session. Two theoretical models make different predictions about why people quit a gambling session. From a behaviourist perspective, people quit a session when they are either satiated or the lack of rewards lead to the extinction of behaviour. Alternatively, from a behavioural-finance perspective, people quit due to the disposition effect: a general finding whereby investors tend to sell shares or other assets when the price has increased, but keep assets that have dropped in value. From the behaviourist perspective, we predict that people experience free spins as a moment of intermittent reinforcement, which should encourage them to continue gambling longer. According to the disposition effect, however, the large win would trigger risk-aversion, signalling an opportunity to "cash out" and lock-in the gain. In the present study, 188 gamblers (72 female) were randomly allocated to one of three conditions: control, early free-spins and late free-spins, in an online EGM simulation (points only). Consistent with the disposition effect, participants who received early free-spins quit earlier, placing significantly fewer bets, than those in control condition. The study suggests that free-spins, rather than being reinforcing within session, may signal an opportunity to quit early. In the discussion, however, we speculate on whether future research could demonstrate that a perceived lack of free spins in a session may keep players engaged longer.

The Conceptual Framework of Harmful Gambling: A revised framework for understanding gambling harm

BACKGROUND AND AIMS

The Conceptual Framework of Harmful Gambling moves beyond a symptoms-based view of harm and addresses a broad set of factors related to the risks and effects of gambling harmfully at the individual, family, and community levels. Coauthored by international research experts and informed by multiple stakeholders, Gambling Research Exchange (GREO) facilitated the framework development in 2013 and retains responsibility for regular updates and mobilization. This review article presents information about the revised version of the Conceptual Framework of Harmful Gambling completed in late 2018.

METHODS

We describe eight interrelated factors depicted in the framework that represent major themes in gambling ranging from the specific (gambling environment, exposure, gambling types, and treatment resources) to the general (cultural, social, psychological, and biological influences). After outlining the framework development and collaborative process, we highlight new topics for the recent update that reflect changes in the gambling landscape and prominent discourses in the scientific community. Some of these topics include social and economic impacts of gambling, and a new model of understanding gambling related harm.

DISCUSSION AND CONCLUSIONS

We address the relevance of the CFHG to the gambling and behavioral addictions research community. Harm-based frameworks have been undertaken in other areas of addiction that can both inform and be informed by a model dedicated to harmful gambling. Further, the framework brings a multi-disciplinary perspective to bear on antecedents and factors that co-occur with harmful gambling.

The Effects of Machine Balance and Free-Spins Features on Machine Preference and Bet Amounts

Across two experiments, the current study investigated whether the balance displayed on slot-machine screens affects gamblers' decision making in a manner similar to the "house-money effect" observed in other gambling modes. The balance indicates the total amount the gambler has available to wager from. We manipulated initial slot-machine balance within a simulated slot-machine task. Participants gambled on each of two machines and then were able to switch between the two allowing us to assess the effect of machine balance on both preference and bet amounts. Experiment 1 also manipulated which machine incorporated a free-spins feature. In both experiments participants preferred to wager on, and made larger bets on, machines with higher balances. Experiment 1 replicated previous findings that people prefer to gamble on machines offering free spins. Together, these two experiments identify balance available as an additional slot-machine feature that contributes to slot-machine gambling behavior.

Cognitive neuroscience can support public health approaches to minimise the harm of 'losses disguised as wins' in multiline slot machines

Video slot machines are associated with both accelerated transition into problematic forms of gambling, as well as psychosocial harm above and beyond other forms of gambling. A growing body of evidence is uncovering how key design features of multiline slot machines produce an inflated experience of reward, despite the fact that these features offer no overall financial benefit to the player. A pernicious example of this are 'losses disguised as wins' (LDWs), which occur when simultaneous bets placed on multiple lines result in a winning combination that returns an amount greater than zero, but less the total wager. These events are usually accompanied by the same celebratory sounds and animations that accompany true wins. We argue that LDWs may leverage neuropsychological phenomena that underlie reinforcement learning and contribute to extended or repetitive use and gambling-related harm. While other characteristics of slot machine gambling have been examined by cognitive neuroscientists, this feature has not yet received attention. Neuroscientific methods can be used to assess the impact of LDWs on the human reward system, to assess the claim that these events are a reinforcing and contributing factor in the development of harmful play. Positive findings would provide further persuasive evidence in support of strategies to minimise gambling harm through the regulation of machine design.