The role of anxiety in modulating temporal processing and sensory hyperresponsiveness in autism spectrum disorder (Atsumi et al. 2025))
One common symptom of autism spectrum disorder, occurring in approximately 90% of individuals with the condition, is heightened responsiveness to sensory stimuli. ASD also has a high comorbidity with anxiety disorders, which increase the response of one’s autonomic nervous system in response to threatening stimuli. With around 20% of adults and 60% of children on the spectrum experiencing some form of anxiety disorder, researchers suspect that these features may be correlated with each other. Specifically, the authors of this study proposed that elevated levels of anxiety could cause increased activation of neural circuits, which could in turn lead to sensory hyperresponsiveness in individuals on the spectrum.
This study used fMRI data to compare the neuronal activation of 25 participants with ASD versus a control group of 25 typically developing individuals. While inside the fMRI, subjects were presented with pictures of two faces, one with a fearful expression and the other with a neutral expression. Next, they were given a simple, unrelated task in which they had to choose which of two shapes appeared on the screen first. Their accuracy and response time was measured and compared across three conditions: no face shown, neutral face shown, or fearful face shown.
No overall correlation was found between the type of face shown and the accuracy of the participants on the simple task. However, participants with lower anxiety scores had faster reaction times on tasks following the “fearful face” condition. Subjects with high anxiety levels did not display this benefit, suggesting that when already in an anxious state, the brain responds less to fearful stimuli. These results were also backed up by fMRI imaging of the anterior insula, a region of the brain involved in processing emotion. Seeing the fearful face stimulus increased activity within the anterior insula, but this effect was dampened in subjects with high anxiety levels.












