Poker-machine gambling: An analysis of within session characteristics

The aim of this study was to examine the nature of poker-machine gambling (the Australian equivalent of British fruit machines and American slot-machines) in an ecologically valid setting. Eighteen regular and 21 occasional poker-machine players were observed, using a methodology that allowed simultaneous recording of machine events, behaviour and cognitions. The results supported previous research by Dickerson et al. (1991, 1992) showing that gambling responses are sensitive to machine events. Larger wins were found to disrupt response rates giving rise to larger post-reinforcement pauses, whereas response rates were maintained by small rewards. In addition, the results showed that the behaviour and beliefs of regular players were more consistent than those of occasional players. Regular players held very fixed views about the profitability of given machines, were less likely to vary their wagers (stakes), and tended to increase their stakes when winning and decrease them when losing. The results also provided some evidence to suggest that poker-machine gambling may be influenced by the beliefs which players hold about the nature of the schedule. The implications of these observations for modern operant conditioning theory are discussed, along with suggestions for further research investigating the relationship between verbal and non-verbal behaviour.