Overly Focused Attention in Adults with Autism

Background: Evidence suggests that the attentional spotlight is overly narrow in autism (e.g., Townsend & Courchesne, 1994). However, it remains unclear whether the problem is strictly one of a narrow beam, or inflexibility in changing its size. Objectives: Examine size and flexibility of the attentional spotlight, and test for corroborating evidence of spatial inattention in autism spectrum disorder (ASD). Methods: High-functioning adults (n = 29) with autism/ASD and matched controls (n = 29) were compared on two tasks. Experiment 1: Size of the attentional spotlight was examined by determining whether individuals with ASD make same-different judgments more quickly and accurately when stimuli are presented closer in space versus farther apart. Switching the size of the attentional beam was assessed by examining the impact on performance of the distance between stimuli on the previous trial. Experiment 2: Spatial inattention/neglect was examined using the greyscales task. Participants were required to judge which of two left-right mirror-reversed brightness gradients was darker. Results: Experiment 1: In ASD, reaction times (RTs) were fastest when stimuli were close together (p's < .01), and this was even more evident when attention was narrowed in the previous trial (p's < .003). In addition, when attention was broadened in the previous trial and remained broad on the current trial, the ASD group made more errors (p = .004). In Controls, RTs and error rates did not differ across conditions. Experiment 2: The ASD group was biased more to the right side of space than controls (p < .05). Conclusions: Our findings implicate both overly narrow and inflexible attention in ASD: the beam appears to be set too “small”, and, once narrowed, attention becomes overly focused, making it difficult to broaden the beam. Evidence suggests further that attention is overly focused to the right side of visual space in ASD.