Grouping-Induced Numerosity Biases Vary with Autistic-Like Personality Traits.

Researchers tested how people with autism-like traits count dots connected by lines. Usually, people undercount when dots are connected because their brain groups them together. But people with more autism-like traits were better at counting accurately - they weren't fooled by the connecting lines. This suggests autistic people may see details more clearly without being distracted by how things are grouped together visually.

This study investigated how autistic-like traits in neurotypical adults affect visual perception using a novel numerosity judgment task. Participants counted dots connected by lines, which typically causes people to underestimate the actual number. Results showed a strong correlation (r=0.72) between autism-spectrum quotient scores and reduced underestimation bias, suggesting individuals with higher autistic traits were less affected by visual grouping effects. The findings support theories that autistic perception involves weaker global processing mechanisms and stronger local detail processing, as those with higher autistic traits appeared less influenced by the visual grouping that causes connected dots to be perceived as unified wholes rather than individual elements.

Findings may help explain enhanced detail-focused processing abilities in autism. Could inform development of visual perception assessments and educational strategies that leverage strengths in local processing while supporting global integration skills when needed.

Study used neurotypical adults with autistic-like traits rather than diagnosed autistic individuals. Sample size not reported. Unclear if findings generalize to clinical autism populations or other visual processing tasks.

Individuals with autism spectrum disorder are thought to have a more local than global perceptual style. We used a novel paradigm to investigate how grouping-induced response biases in numerosity judgments depend on autistic-like personality traits in neurotypical adults. Participants judged the numerosity of clouds of dot-pairs connected by thin lines, known to cause underestimation of numerosity. The underestimation bias correlated strongly with autism-spectrum quotient (r = 0.72, Bayes factor > 100), being weaker for participants with high autistic traits.

As connecting dots probably activates global grouping mechanisms, causing dot-pairs to be processed as an integrated whole rather than as individual dots, the results suggest that these grouping mechanisms may be weaker in individuals self-reporting high levels of autistic-like traits.