Executive Function in Gambling Disorder: A Meta-analysis on Neuropsychological Evidence

Gambling disorder (GD) is associated with deficits in various cognitive functions. Specifically for executive function (EF), previous findings are inconsistent, despite deficits being reported for shifting, inhibition, planning, and working memory domains. Although a worse performance in EF measures related to GD severity is often reported, there is a need to clarify current evidence. This study aims to systematically review and perform a meta-analysis to clarify the association between EF deficits and GD. The current study followed the preferred reporting items for systematic reviews and meta-analyses protocols. The meta-analysis used a random effects model and robust variance estimation to analyze the data, using Hedge's g to report effect sizes. A total of 21 studies were systematically reviewed, of which 17 were included for meta-analysis. Meta-analysis was performed for shifting, inhibition, planning, and verbal fluency. Due to a lower number of studies, working memory data was systematically reviewed, but no meta-analysis was performed. Significant effect sizes were found for shifting and inhibition, indicative of deficits in participants with GD. No significant deficits were found for the other EF domains. Working memory results revealed inconsistent evidence, even when divided into verbal and visuospatial modalities. There is enough evidence of deficits in shifting and inhibition in participants with GD. However, better sample characterization should be considered in future studies to better understand the sources of potential heterogeneity. Consideration of gambling severity as a continuous variable could allow for a more detailed analysis of EF alterations across the various degrees of GD.