How many times do I need to see to believe? The impact of intolerance of uncertainty and exposure experience on safety-learning and retention in young adults.

Individuals who score high in self-reported Intolerance of Uncertainty (IU) display difficulties updating threat associations to safe associations. Here we sought to determine whether individuals who score high in IU can learn and retain new safety associations if given more exposure. We recorded skin conductance response, pupil dilation and expectancy ratings during an associative threat learning task with acquisition, same-day extinction and next-day extinction phases. Participants (n = 144) were assigned to either a regular exposure (32 trials of same-day and next-day extinction) or extended exposure condition (48 trials of same-day and next-day extinction). We failed to replicate previous work showing that IU is associated with poorer safety-learning indexed via SCR. We found preliminary evidence for promoted safety-retention in individuals with higher Inhibitory IU in the extended exposure condition, relative to individuals with higher Inhibitory IU in the regular exposure condition, indexed via SCR. These findings further our current understanding of the role of IU in safety-learning and -retention, informing models of IU and exposure-based treatments.