Objective: This study aimed to assess age-related changes in Stroop Color and Word test indices in individuals with high-functioning pervasive developmental disorder (HF-PDD) and compare their performance with typically developing (TD) individuals.
Methods: There were a total of 125 participants (57 TD, 68 HF-PDD), aged 6-24. Stimuli were displayed on computer screens, and participants verbally responded with response times recorded via voice key function.
Results: Single regression analysis revealed age-associated trends in Stroop test indices for both groups, indicating shorter response times and reduced Stroop interference with age. The age at which the best Stroop test results were obtained ranged from 220 to 260 months for TD and from 195 to 201 months for HF-PDD. While color naming and word reading tasks showed no significant group differences, color word naming task response times were significantly longer for the HF-PDD group. Around 30% of HF-PDD participants scored over two standard deviations above the TD mean.
Conclusions: Both TD and HF-PDD groups exhibited age-related changes in Stroop task performance, which were fitted by a quadratic regression curve. Prolongation of the color word naming task in the HF-PDD group suggests that approximately 30% of individuals with HF-PDD have difficulty with stereotype suppression. J. Med. Invest. 71 : 254-259, August, 2024.
Keywords: Stroop test; frontal lobe function; high-functioning pervasive developmental disorder; stereotype suppression.