The mental simulation of state/psychological stimuli in anxiety disorders: A 3T fMRI study.

Mental imagery plays an important role in cognitive and emotional processes, therefore it might contribute to psychopathology in affective disorders. Distressive intrusive imagery is a core feature of anxiety disorders, but the underlying neurobiology remains unexplored. Here, we examined the functional brain mechanisms involved in state/psychological imagery in individuals with anxiety disorders. Functional Magnetic Resonance Imaging (fMRI) was used to assess the brain circuits involved in state/psychological (vs. action) imagery controlled by letter detection on the same stimuli in 33 individuals with anxiety disorders relative to 33 healthy controls. Patients were faster than controls in processing state/psychological stimuli and in general in the imagery task. We found that the left superior frontal gyrus was differentially activated by the state/psychological (vs. action) imagery (vs. letter detection) in the anxious individuals vs. healthy controls. We suggest that this area, which is involved in processing of state/psychological semantic information, appears deregulated during imagery in subjects with anxiety disorders. Our study provided the first evidence of both behavioral and brain functional alterations during imagery, highlighting a key role of the left superior frontal gyrus.