Standard IQ Test May Undervalue People With Autism

June 20 -- FRIDAY, June 19 (HealthDay News) -- The most commonly used test to measure intelligence is underestimating the intellectual potential of autistic people, new research suggests.

People with autism often struggle with the verbal portions of the Wechsler Adult Intelligence Scale, the test most often used to measure IQ, researchers said.

But when given another test of abstract reasoning abilities, the Raven's Standard Progressive Matrices, autistic people not only had scores equal to those of their non-autistic counterparts, but they answered the questions, on average, as much as 42 percent more quickly.

On the Raven's test, autistic participants scored, on average, 30 percentage points higher than would have been predicted by their scores on the Wechsler scale, according to the study, in the June issue of Human Brain Mapping.

Also, MRIs done during the testing showed that autistic people had more activity in different areas of their brains than those without autism.

"While both groups performed Raven's Standard Progressive Matrices (RSPM) test with equal accuracy, the autistic group responded more quickly and appeared to use perceptual regions of the brain to accelerate problem solving," said Isabelle Soulieres, a post-doctoral fellow at Harvard University and the study's lead author. "Some critics argued that autistics would be unable to complete the RSPM because of its complexity, yet our study shows autistics complete it as efficiently and have a more highly developed perception than non-autistics."

The researchers said the findings have implications for the way in which autistic children are educated.

"When we do the Wechsler test, which is the one that is done in clinical settings, there is a big chance that we underestimate the education potential of autistics," Soulieres said. "If you underestimate someone's potential, you will have less hope and you will lower your goals for this person. … We should make the bet they are more intelligent than they show us on the Wechsler test."