Slot is a game in which you spin the reels and hope to match up symbols on a pay-line. These symbols can be anything from classic card suits (A, K, Q, J) to stylized icons fitting the theme of the game. Many slots have themes inspired by films, music, or other popular culture.
Unlike most other forms of gambling, slot machines offer players instant feedback on their winnings and losses. Wins are accompanied by high-fidelity, attention-grabbing music and amusing animations. Moreover, the relative frequency of wins and losses on slot machines is unknown to the player and their monetary rewards are delivered according to an intermittent reinforcement schedule (Griffiths and Parke, 2005; Haas and Edworthy, 1996). This combination of factors makes slots play an especially potent attractor for some people, but can also lead to severe gambling problems such as mounting financial debt, social difficulties, professional issues, and involvement in criminal activities to support the habit (Blaszczynski, Sharpe, Walker, Shannon, and Coughlan, 2005).
The current study sought to determine whether the sounds that accompany slot machine plays increase or decrease arousal. Participants rated the arousal of playing slots with and without sound. They then completed a series of questionnaires including the Canadian Problem Gambling Index (CPGI), the PGSI component of the CPGI, a self-report measure of flow during mind-wandering, and two other scales for purposes peripheral to the experiment (the GEQ and the DASS-21).
A nine-line realistic simulator was used to simulate slot machine play. A virtual payout counter displayed the number of credits won per spin, and a “win” indicator showed a varying color when a line win occurred. A force transducer was fixed underneath the spin button, and a volt signal was recorded by AD Instruments PowerLabs when the button was depressed to initiate a spin. In the sound-on condition, a musical instrument-inspired soundtrack was played along with these visual and auditory cues. A counter flashed zero for regular losses and progressively increased in value for LDWs and wins. The combination of symbols responsible for the line win was shown on screen as a coloured line connecting them.
In the sound-off condition, all of these features were absent. Despite the absence of the soundtrack, players still overestimated how often they won, on average estimating that they won 33 times when in reality they were only exposed to 28 wins. This result provides empirical evidence that the sounds of a slot machine contribute to its enticing appeal, as they lead to a more exaggerated sense of win frequency and arousal. This finding is important, as the overestimation of wins may have a direct effect on the severity of gambling-related problems. Further research will be necessary to explore the exact nature of this relationship. Until then, researchers will continue to study the effects of sounds in the context of other sensory modalities such as video games and online casino games. This will help us understand the precise mechanisms that underlie gambling enticement and how these can be modified to reduce problematic behavior.