Psychobiological approach to pathological and problematic gambling and gaming: systematic literature review

Gambling and gaming behaviours and associated problems arising from excessive use have received increasing attention from the scientific community and from clinicians in recent years. Problems have accompanied the easier access to betting and casino-like games, and the establishment of online gambling/gaming as an important recreational activity. The addictive power of games and its negative impact on personal, family, professional and financial domains is widely recognized. Although there are parallels with substance dependence, relatively little is known about these behavioural dependences. Thus, it is important to understand the underlying psychobiological mechanisms that can increase the chances of an individual becoming a pathological gambler/gamer. Among other factors, it appears important to better understand the role of the near-miss effect (i.e., the unrealistic expectation that a reward will occur due to results of a near win situation) in the development of gambling and gaming disorders and the methods used in its study. This systematic review analyses the methods used in the study of the near-miss effect, namely experimental protocols involving the analysis of behavioural responses and their neurobiological correlates, utilizing neurophysiological techniques (electroencephalography [EEG] and event-related potentials [ERPs]). Studies with the main purpose of evaluating the role of the near-miss effect in gambling and gaming disorders were retrieved from multiple literature databases, accordingly to inclusion and exclusion criteria. The inclusion and analysis of the studies followed PRISMA-P and Cochrane Collaboration Guidelines. Results showed that few empirical studies have focused on the neuropsychobiological correlates of gambling and gaming behaviours, which would promote a better understanding of these disorders. Findings from previous studies mostly deal with behavioural or self-reported data and are often controversial, possibly due to small and heterogeneous samples, as well as heterogeneous methods. The literature suggests that the near-miss effect (i.e., losing by little) involves brain reward-related areas, including the ventral striatum, increasing the gambling behaviour supposedly by strengthening the illusion of control. Due to the importance that such an effect appears to have on problematic and pathological gambling behaviour, the development of further knowledge about this effect is essential. This goal can be achieved through a transdisciplinary research approach, in which behavioural analysis could be combined with data from less explored neuroscience techniques, namely electroencephalography (EEG) and neuroimaging techniques such as functional magnetic resonance imaging (fMRI). Special attention should be paid to the sampling procedures, namely to the gamblers' characteristics that might have confounding effects on the results (e.g., type and severity of gambling behaviours, executive functioning, affective and personality traits), so that research can move forward, producing additional scientific evidence that supports the understanding of this disorder.