Understanding Behavioural Rigidity in Autism Spectrum Conditions: The Role of Intentional Control.

Poljac et al. (2017) asked autistic people to pick between two simple computer tasks over and over.

They could repeat the same task or switch to the other one. The team measured how often people repeated and how long it took to switch.

The goal was to see if trouble forming a new intention—not just moving muscles—explains rigid behavior in autism.

Autistic participants repeated the same task far more often than non-autistic peers.

When they did try to switch, they took longer and made more errors.

The pattern points to a bottleneck at the “I’ll do the other thing now” stage, not at the hand-moving stage.

Poljac et al. (2012) saw the same repetition bias in college students with high autistic traits, hinting the problem exists before an autism diagnosis is given.

Lacroix et al. (2022) sharpen the picture: switch costs only show up when the change is unpredictable and loaded with social-emotional cues, not when rules are clear.

Hoyle et al. (2022) add that repetitive behaviors jump when kids must both inhibit and switch at the same time, matching the idea that intentional control has a limited fuel tank.

If rigidity starts when the brain is forming the new intention, simply prompting “try something different” may fail. Instead, give the learner a brief pause before the switch cue, pre-state the new rule, and cut extra demands during the change. These tiny schedule tweaks can lower the intention-forming load and make flexibility training stick.