It has been argued that electronic gaming machines (EGM) are extremely addictive, often described as the "crack cocaine of gambling". Little research has been conducted on the psychophysiology of gambling behaviours. This study used state-of-the-art technology to investigate the effect of gambling outcome (wins and losses) and betting stake (high and low) on physiological responding. HR and SCL were recorded on a second-bysecond basis to win and loss events in high and low stake conditions while healthy controls (N=43) gambled on an EGM. The relationship between personality (impulsivity and reward/punishment sensitivity) and physiological responding to wins and losses were also investigated. Results indicated that psychophysiological measures were sufficiently sensitive to detect subtle changes in physiological responding. Wins resulting in SCL and HR increases, this pattern was amplified during the higher betting stake condition, for SCL only. Personality traits failed to demonstrate a relationship with physiological responding. The current study demonstrates that physiological changes associated with gambling on an EGM can be measured reliably, and are sensitive to gambling outcome and stake manipulations. The present study is an essential first step in determining whether problem gamblers can be identified by a physiologically distinctive pattern of responding to events on an EGM.