Deciphering reward-based decision-making in schizophrenia: A meta-analysis and behavioral modeling of the Iowa Gambling Task

Abstract

Background: Patients with schizophrenia (SZP) have been reported to exhibit impairments in reward-based decision-making, but results are heterogeneous with multiple potential confounds such as age, intelligence level, clinical symptoms or medication, making it difficult to evaluate the robustness of these impairments. Methods: We conducted a meta-analysis of studies comparing the performance of SZP and healthy controls (HC) in the Iowa Gambling Task (IGT) as well as comprehensive analyses based on subject-level data (n = 303 SZP, n = 188 HC) to investigate reward-based decisionmaking in SZP. To quantify differences in the influence of individual deck features (immediate gain, gain frequency, net loss) between SZP and HC, we additionally employed a least-squares model. Results: SZP showed statistically significant suboptimal decisions as indicated by disadvantageous deck choices (d from 0.51 to-0.62) and lower net scores (d from-0.35 to-1.03) in a meta-analysis of k = 29 samples (n = 1127 SZP, n = 1149 HC) and these results were confirmed in a complementary subject-level analysis. Moreover, decision-making in SZP was characterized by a relative overweighting of immediate gain and net losses and an underweighting of gain frequency. Moderator analyses revealed that in part, decision-making in the IGT was moderated by intelligence level, medication and general symptom scores. Conclusion: Our results indicate robust impairments in reward-based decision-making in SZP and suggest that decreased cognitive resources, such as working memory, may contribute to these alterations.

Obsessive-Compulsive Disorder and Decision Making under Ambiguity: A Systematic Review with Meta-Analysis

“…The mean IGT difference between OCD and HC was −0.65 in our meta-analysis, and this might seem a low value to be clinically significant; however, our standardized mean difference (SMD) is in line with the SMD of other meta-analysis reporting a relevant clinical difference at the IGT between healthy controls and other neuropsychiatric populations [63][64][65][66]. Most importantly, the SMD resulting from our meta-analysis is close to the one of a meta-analysis comparing HC and pathological gamblers (d = −1.03) [63].…”

Polygenic Risk Scores for Psychiatric Disorders Reveal Novel Clues About the Genetics of Disordered Gambling

“…Relative to healthy controls, individuals with DG (Kovács, et al, 2017) and SCZ (Betz, et al, 2019;Woodrow, et al, 2018) exhibit impaired decision-making abilities on the Iowa Gambling Task (IGT; Bechara, et al, 1994). The IGT is a complex task that taps a multifaceted construct, and can reflect effects originating in a number of neural systems related to bottom-up impulsive processes and top-down reflective impulse control (Bechara, 2005;Buelow & Suhr, 2009).…”

The Prominent Deck B Phenomenon in Schizophrenia: An Empirical Study on Iowa Gambling Task

“…The contrasting results in Sz-IGT studies were likely due to the heterogeneity of characteristics of participants and methodological approaches (e.g., disparate outcome measures of IGT). Types of antipsychotic treatments (Beninger et al, 2003), doses of medication (Betz et al, 2018), diagnoses (Betz et al, 2018), clinical symptoms (Betz et al, 2018), intelligence level (Betz et al, 2018), age (Carvalho et al, 2012), gender (Singh et al, 2020), and education (Evans et al, 2004) affect decision-making performance in Sz cases. However, no conclusions based on the above factors could be made to reach a consensus.…”

“…Review and meta-analysis studies have provided behavioral evidence that Sz has impaired reward-based decision-making process (Brown et al, 2015;Betz et al, 2018). In terms of the evidence from neuroimaging studies, Sz cases show hypofrontality with fewer activations in the frontal cortex, including dorsolateral frontal cortex (DLPFC) assessed with the Wisconsin Card Sorting Test (WCST) (Riehemann et al, 2001).…”