A Functional Anatomy of Anticipatory Anxiety

Anticipatory anxiety is a complex combination of a future-oriented cognitive state, negative affect, and autonomic arousal. A dual-task paradigm of anticipation of electric shocks and a motor-learning task was used to examine the changes in neural patterns of activation associated with modulation of the cognitive state in anxiety by a distracting motor task. We used positron emission tomography (PET) and15O-water to measure regional cerebral blood flow (rcbf) in 10 healthy male volunteers. A 2 × 2 factorial design-(shock vs no shock) × (low vs high distraction) was used with three scans per condition. Twelve PET scans were performed on each subject. In six of these scans, subjects were given electric shocks. In all scans, subjects also simultaneously performed a motor repetition (low distraction) or learning (high distraction) task. Galvanic skin conductance (GSR), Spielberger State and Trait Anxiety Inventory (STAI), and self-report data were also collected. In comparisons between the shock and no-shock conditions, the main finding was of increased rcbf in the left insula (−38,8,8) (z=4.85,P