Introduction: Behavioral experiments on reaction time indicate that anxious subjects' vigilance-related attention is biased towards threatening words, though direct data on cerebral activity associated to this bias are conspicuously scarce.
Methods: In the present study, event-related potentials (ERPs) were recorded from 30 subjects, grouped according to their scores in trait and state anxiety questionnaires. The specific role of the arousal and valence content of the stimulation in the vigilance bias was investigated by blocking the arousal content. Stimulation with high biological significance was employed. An S1 (sound)-S2 (emotional picture) task ensured that subjects were vigilant towards positive, negative or control (neutral) images.
Results: Only subjects presenting high state scores and high state-trait combination scores showed significantly higher amplitudes in the Early Contingent Negative Variation during vigilance towards negative stimuli. This ERP component typically appears between S1 and S2 and reflects the intensity of vigilance.
Conclusions: ERP activity detects cerebral indices that confirm the presence of valence-related vigilance biases in anxiety.