Environmental Enrichment Attenuates Repetitive Behavior and Alters the Functional Connectivity of Pain and Sensory Pathways in C58 Mice.

Restricted repetitive behaviors (RRB) encompass a variety of inflexible behaviors, which are diagnostic for autism spectrum disorder (ASD). Despite being requisite diagnostic criteria, the neurocircuitry of these behaviors remains poorly understood, limiting treatment development. Studies in translational animal models show environmental enrichment (EE) reduces the expression of RRB, although the underlying mechanisms are largely unknown. This study used functional magnetic resonance imaging to identify functional connectivity alterations associated with RRB and its attenuation by EE in C58 mice, an animal model of RRB. Extensive differences were observed between C58 mice and C57BL/6 control mice. Higher RRB was associated with altered connectivity between the somatosensory network and reticular thalamic nucleus and between striatal and sensory processing regions. Animals housed in EE displayed increased connectivity between the somatosensory network and the anterior pretectal nucleus and hippocampus, as well as reduced connectivity between the visual network and area prostriata. These results suggest aberrant sensory perception is associated with RRB in C58 mice. EE may reduce RRB by altering functional connectivity in pain and visual networks. This study raises questions about the role of sensory processing and pain in RRB development and identifies new potential intervention targets.