Decision-making in blackjack : an electrophysiological analysis

Previous studies have identified a negative potential in the event-related potential (ERP), the error-related negativity (ERN), which is claimed to be triggered by a deviation from a reward expectation. Furthermore, this negativity is related to shifts in risk taking, strategic behavioral adjustments, and inhibition. We used a computer Blackjack gambling task to further examine the process associated with the ERN. Our findings are in line with the view that the ERN process is related to the degree of reward expectation. Furthermore, increased ERN amplitude is associated with the negative evaluation of ongoing decisions, and the amplitude of the ERN is directly related to risk-taking and decision-making behavior. However, the findings suggest that an explanation exclusively based on the deviation from a reward expectation may be insufficient and that the intention of the participants and the importance of a negative event for learning and behavioral change are crucial to the understanding of ERN phenomena

Hypersensitivity to reward in problem gamblers

Background: Recent research has begun to examine the neurophysiologic basis of pathological gambling. However, direct evidence of a behavioral deficit and an accompanying neurofunctional deviation in a realistic gambling context such as Black Jack has not yet been reported. Methods: Electroencephalogram was recorded while 20 problem gamblers and 21 control participants played a computerized version of Black Jack. Participants were asked to decide at point scores between 11 and 21 whether they wanted to take another card ("hit") to arrive closer to 21 than the opponent (simulated by computer) or not to take another card ("sit") to avoid going over 21 ("bust"). Results: At a critical point score of 16, problem gamblers decided more often to hit despite losses due to a bust on the preceding trial, whereas control participants decided more often to sit under these conditions. Furthermore, problem gamblers showed more reward-related positive amplitudes in the event-related brain potential than control participants after successful hit decisions at 16. Conclusions: Here we provide experimental evidence for high-risk taking behavior in gamblers and its correlate in event-related brain potentials. Our results suggest that high-risk-taking behavior in problem gamblers is associated with an increased reward-related neural response to infrequent successes of this behavior