Affective neuroimaging in generalized anxiety disorder: an integrated review

Affective neuroimaging has contributed to our knowledge of generalized anxiety disorder (GAD) through measurement of blood oxygenation level-dependent (BOLD) responses, which facilitate inference on neural responses to emotional stimuli during task-based functional magnetic resonance imaging (fMRI). In this article, the authors provide an integrated review of the task-based affective fMRI literature in GAD. Studies provide evidence for variable presence and directionality of BOLD abnormalities in limbic and prefrontal regions during reactivity to, regulation of, and learning from emotional cues. We conclude that understanding the sources of this variability is key to accelerating progress in this area. We propose that the cardinal symptom of GAD-worry-predominantly reflects stimulus-independent mental processes that impose abnormal, inflexible functional brain configurations, ie, the overall pattern of information transfer among behaviorally relevant neural circuits at a given point in time. These configurations that are inflexible to change from the incoming flux of environmental stimuli may underlie inconsistent task-based findings.