The anti-COVID-19 vaccination campaign in the United States provided a significant contribution to the control of the virus spread. Despite the recommendations by public health institutions, vaccine skepticism and hesitancy contributed to low vaccine uptake, thus possibly disrupting the management of preventable diseases associated with the COVID-19 infection. The process that led individuals to accept COVID-19 vaccines required the ability to gather, synthesize, and weigh-up information within a novel, dynamically changing, complex, and ambiguous context. To deal with such complexity, we hypothesized that both the ability of reflection and flexible adaptation played a fundamental role. Based on previous research on cognitive predictors of vaccine refusal, we decided to investigate the combined role of two constructs, namely, problem-solving skills and socio-cognitive polarization (SCP), on vaccine acceptance and uptake. Two-hundred-seventy-seven US participants completed an online survey aimed to measure problem-solving ability, through a rebus puzzles task, and SCP, through a composite measure of absolutist thinking, political conservatism, and xenophobia. Mediation analyses indicated that SCP mediated the association between problem-solving ability and vaccine acceptance, so lower problem-solving abilities associated with higher polarization predicted vaccine rejection. Thus, our findings suggested that low problem-solving skills may represent a risk factor for COVID-19 vaccine refusal, with cognitive and social rigidity playing a crucial role in undermining the anti-COVID-19 vaccine uptake.
