Atypical scene-selectivity in the retrosplenial complex in individuals with autism spectrum disorder
A small behavioral literature on individuals with autism spectrum disorder (ASD) has shown that they can be impaired when navigating using map-based strategies (i.e., memory-guided navigation), but not during visually guided navigation. Meanwhile, there is neuroimaging evidence in typically developing (TD) individuals demonstrating that the retrosplenial complex (RSC) is part of a memory-guided navigation system, while the occipital place area (OPA) is part of a visually-guided navigation system. A key identifying feature of the RSC and OPA is that they respond significantly more to pictures of places compared to faces or objects - i.e., they demonstrate scene-selectivity. Therefore, we predicted that scene-selectivity would be weaker in the RSC of individuals with ASD compared to a TD control group, while the OPA would not show such a difference between the groups. We used functional MRI to scan groups of ASD individuals and matched TD individuals while they viewed pictures of places and faces and performed a one-back task. As predicted, scene-selectivity was significantly lower in the RSC, but not OPA, in the ASD group compared to the TD group. These results suggest that impaired memory-guided navigation in individuals with ASD may, in part, be due to atypical functioning in the RSC. Lay summaryThe retrosplenial complex (RSC), a cortical region that is part of a neural system that supports our ability to form map-like mental representations of the environment and use them to navigate (i.e., memory-guided navigation), exhibits atypical responses to images of places in individuals with autism spectrum disorder (ASD). These results are a first step towards understanding the neural mechanisms responsible for understudied behavioral impairments in memory-guided navigation in individuals with ASD.