Most people learn when to be afraid and when things are not as bad as they might have once seemed but some new research on autism shows that children with the diagnosis don't easily let go of old, outdated fears and that this rigid fearfulness is linked to the severity of classic symptoms of autism, such as repeated movements and resistance to change.

The new research highlights the need to help children make emotional transitions – particularly when dealing with their fears.

In the study, psychologists recruited 30 children diagnosed with autism and 29 without to participate in an experiment. After seeing a visual cue like a yellow card, the participants would feel a harmless but surprising puff of air under their chins. Part-way through the experiment, the conditions changed so that a different color preceded the puff of air. The researchers measured participants' skin response to see if their nervous system noticed the switch and knew what was coming.

Typical kids adjusted quickly to the new color instead of the old one. The amount of time it took to extinguish the original fear correlated with the severity of hallmark symptoms of autism.

"People with autism likely don't experience or understand their world in the same way we do," said Mikle South, a psychology professor at Brigham Young University and lead author of the study. "Since they can't change the rules in their brain, and often don't know what to expect from their environment, we need to help them plan ahead for what to expect."

Persistent, needless fears are detrimental to physical health. The elevated hormone levels that aid us in an actual fight or flight scenario will cause damage to the brain and the body if sustained over time. South said the families who participate in social skills groups can relate to the new findings.

"In talking to parents, we hear that living with classic symptoms of autism is one thing, but dealing with their children's worries all the time is the greater challenge," South said. "It may not be an entirely separate direction to study their anxiety because it now appears to be related."

Citation: Mikle South, Tiffani Newton, Paul D. Chamberlain, 'Delayed Reversal Learning and Association With Repetitive Behavior in Autism Spectrum Disorders', Autism Research DOI: 10.1002/aur.1255