Behavioral expressions of intolerance of uncertainty in worry. Experimental findings.

Ladouceur et al. (1997) tested how people who worry a lot react to unclear tasks. They gave adults puzzles that were a little fuzzy. Then they watched who asked for extra clues.

The team scored each person on intolerance of uncertainty. That is how much unknown feels upsetting. They wanted to see if high scorers hunt for more info when tasks sit in the middle zone of unclear.

People with high intolerance of uncertainty asked for more hints only when the task was moderately fuzzy. When tasks were very clear or very vague, they did not ask for extra clues.

The study supports a threshold model. Worry-driven checking pops up at middle levels of doubt, not at the extremes.

Brosnan et al. (2025) extends this idea to autism traits. They show intolerance of uncertainty explains why autistic adults think longer before deciding. Both papers point to the same core: a strong need for predictability drives extra evidence gathering.

Stevens et al. (2018) adds a twist. They found worry makes future predictions more negative, but does not change how many options people list. Ladouceur et al. (1997) looked at cue seeking, not prediction tone. Together they tell us worry changes both behavior and content, just in different ways.

Kingston et al. (2010) shift the lens to avoidance. They show avoiding inner feelings links to many problem behaviors. Ladouceur et al. (1997) show active information seeking instead of avoidance. The two papers seem opposite, but both fit a rule: people cope with discomfort either by chasing info or by shutting down, depending on the task.

If you assess worry or rigid rule following, add tasks with graduated ambiguity. Start clear, then slide into fuzzy. Watch if the client only asks questions in the middle zone. That pattern gives you a quick window into intolerance of uncertainty without a long survey. You can then teach flexible problem solving right at that middle level where the discomfort peaks.