Expression levels for the activity-dependent immediate early gene, Arc, (Guzowski et al., 1999; Ramírez-Amaya et al., 2005) were measured in brain regions associated with anxiety-like behavior (the amygdala, Gray and McNaughton, 2000; LeDoux, 2000), visual perception (cortical area V1, McCurry et al., 2010), and spatial navigation (hippocampus, Guzowski et al., 2001). Here, ARC is linked to Anxiety.