ResearchBlogging.orgEarlier this year a study published in the Journal of Neuroscience looked at the brains of compulsive gamblers and concluded that when the the gamblers suffered “near-miss” losses their brains reacted as if they had won. Another study published slightly later in the Journal of the Experimental Analysis of Behaviour also looked at the brains of gamblers but included a control groups of non-gamblers as well. The results were interesting.

First off, what exactly is a near-miss loss? The experiments were performed with slot machine type visual stimuli so in this case lines that contained two out of three matching symbols were considered near-misses. Now from a practical stand point, as the out put is meant to be random a line like this is no closer to winning than one with three different symbols and does not predict any greater likelihood of winning in the future. Although people might realise this from an intellectual stand point it’s still hard not to think “Almost got it that time”.  Hence “near-miss”.

The second study did indeed find that gamblers reacted to the near misses more like they were wins, they also found that non-gamblers reacted to the near misses more as if they were true losses. The thing I found interesting though was that the reactions of gamblers to winning while consistent within the gambling group had nothing in common with the reaction in the non-gambling group.

A further interesting finding was that although the non-gambler group had neural responses more similar to losses when confronted with near-misses, they gave similar answers as the gamblers when asked how close they were to a win. In other words they also rated a near-miss as closer to winning than a more random looking output.

By comparing the neural activation of gamblers and non-gamblers the researchers were able to see that non-gamblers had stronger reactions to losing outcomes than did the gamblers. This makes sense in several ways, humans are generally quite loss averse. We will tend to think of a loss as more negative than a similar gain is positive ie a win of a certain amount versus a loss of the same amount do not cancel out, there is a larger negative emotional balance. In contrast, problem gamblers would be expected to view losses as less damaging over all otherwise continuing losses would result in ceasing gambling activities.

In addition the study authors linked this work with a previous study, suggesting that problem gamblers are activating regions  of their brains associated with impulsive behaviour when wins are experienced while non-gamblers activate regions associated with reflective behaviour when experiencing losses. This part of the study discussion is very interesting and worth a read in itself.

The current study is insufficient to establish the causal direction in the relationship between compulsive gambling behaviour and the network of neural activation that accompanies gambling wins. Even so it is tempting to view the brain response as predisposing a person to becoming a compulsive gambler.  If the “high” for a win is greater in certain individuals because of this difference in brain response then this might lead them to gambling abuse behaviour. I hardly think though that there will ever be wide-scale screening programmes to identify potential gamblers.

The more we learn about the functioning of the brain in these sort of situations though the better equipped we will be to effectively help those who are affected by problem gambling.


OpenLab2010 Submit To Open Laboratory 2010(What’s This?)

Chase, H., & Clark, L. (2010). Gambling Severity Predicts Midbrain Response to Near-Miss Outcomes Journal of Neuroscience, 30 (18), 6180-6187 DOI: 10.1523/JNEUROSCI.5758-09.2010

Habib, R. & Dixon, M.R. (2010). Neurobehavioral evidence for the “near-miss” effect in pathological gamblers JOURNAL OF THE EXPERIMENTAL ANALYSIS OF BEHAVIOR, 93 (3), 313-328 : 10.1901/jeab.2010.93-313

Enhanced by Zemanta