Anxiety positive subjects show altered processing in the anterior insula during anticipation of negative stimuli

Alan N. Simmons, Murray B. Stein, Irina A. Strigo, Estibaliz Arce, Carla Hitchcock, Martin P. Paulus

Prior neuroimaging studies support the hypothesis that anticipation, an important component of anxiety, may be mediated by activation within the insular and medial prefrontal cortices including the anterior cingulate cortex. However, there is an insufficient understanding of how affective anticipation differs across anxiety groups in emotional brain loci and networks. We examined 14 anxiety positive (AP) and 14 anxiety normative (AN) individuals completing an affective picture anticipation task during functional magnetic resonance imaging (fMRI). Brain activation was examined across groups for cued anticipation (to aversive or pleasant stimuli). Both groups showed greater activation in the bilateral anterior insula during cued differential anticipation (i.e., aversive vs. pleasant), and activation on the right was significantly higher in AP compared to AN subjects. Functional connectivity showed that the left anterior insula was involved in a similar network during pleasant anticipation in both groups. The left anterior insula during aversive and the right anterior insula during all anticipation conditions coactivated with a cortical network consisting of frontal and parietal lobes in the AP group to a greater degree. These results are consistent with the hypothesis that anxiety is related to greater anticipatory reactivity in the brain and that there may be functional asymmetries in the brain that interact with psychiatric traits.