Evidence of Altered Fear Extinction Learning in Individuals with High Vaccine Hesitancy During Covid-19 Pandemic.

Objective: A relevance of fear and concerns about vaccine development and its side effects are suggested to explain COVID-19 vaccine hesitancy. However, evidence supporting the phobic origin hypothesis of hesitancy for COVID-19 and other vaccinations remains indirect and elusive. Method: We addressed this issue by investigating the existence of a relationship between fear conditioning, extinction, and the respective vaccination hesitancy and anxiety scores in a group of 25 individuals. Results: Overall, we show that the general mechanism of fear extinction learning is impaired in individuals with high vaccine hesitancy. State and trait anxiety scores do not account for this result. Conclusions: These findings suggest that attitudes against vaccination could be linked to an altered inhibitory learning process.