Hierarchical Processing in ASD is Driven by Exaggerated Salience Effects, not Local Bias

Area of Science:

• Cognitive psychology
• Neurodevelopmental disorders
• Autism spectrum disorder research

Background:

• Previous research on autism spectrum disorder (ASD) and hierarchical visual processing has yielded inconsistent findings.
• The role of stimulus salience, particularly how it influences global versus local processing, remains unclear in ASD.

Purpose of the Study:

• To investigate the influence of relative salience on hierarchical visual processing in individuals with ASD.
• To determine if differences in global or local processing, or a local bias, exist in ASD compared to neurotypical controls.

Main Methods:

• A Navon letters task was administered to participants with ASD and typically developing controls.
• Stimuli were presented under conditions of global salience, local salience, or equal salience.
• Performance was analyzed based on the level of processing (global vs. local) and target/distractor salience.

Main Results:

• No significant group differences were found in the level of processing (global or local).
• Autism spectrum disorder (ASD) participants did not exhibit a local bias.
• Both groups performed better when targets were more salient than distractors; however, ASD participants showed increased sensitivity to distractor salience.

Conclusions:

• Inconsistent findings regarding global/local processing in ASD may be attributed to exaggerated salience effects, particularly at the distractor level.
• This heightened sensitivity to distractor salience in ASD could explain performance variations in hierarchical processing tasks.