Anxiety disorders have been linked to a hyperactivated cortico-amygdalar circuitry, but the amygdala's role in the pathophysiology of obsessive-compulsive disorder (OCD) remains unclear. This fMRI study examined the cortico-limbic correlates of individually tailored symptom provocation in 14 unmedicated OCD patients and 14 controls. In addition to OCD-relevant pictures, aversive and neutral control stimuli were included. Patients showed increased fronto-striatal activation to OCD-relevant stimuli contrasted with both control categories. Briefly presented symptom-related triggers elicited stronger amygdala engagement in patients than in controls. This effect, however, did also occur to aversive stimuli and was not symptom specific. Augmented amygdala involvement in patients reflects general emotional hyperarousal. Symptom-specific frontal activation points towards a sustained endeavor to suppress exaggerated emotional responses to OCD triggers.

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Research from the previous decade suggests that word meaning is partially stored in distributed modality-specific cortical networks. However, little is known about the mechanisms by which semantic content from multiple modalities is integrated into a coherent multisensory representation. Therefore we aimed to characterize differences between integration of lexical-semantic information from a single modality compared with two sensory modalities. We used magnetoencephalography in humans to investigate changes in oscillatory neuronal activity while participants verified two features for a given target word (e.g., "bus"). Feature pairs consisted of either two features from the same modality (visual: "red," "big") or different modalities (auditory and visual: "red," "loud"). The results suggest that integrating modality-specific features of the target word is associated with enhanced high-frequency power (80 -120 Hz), while integrating features from different modalities is associated with a sustained increase in low-frequency power (2-8 Hz). Source reconstruction revealed a peak in the anterior temporal lobe for low-frequency and high-frequency effects. These results suggest that integrating lexical-semantic knowledge at different cortical scales is reflected in frequency-specific oscillatory neuronal activity in unisensory and multisensory association networks.

Temporal allocation of attention is often investigated with a paradigm in which two relevant target items are presented in a rapid sequence of irrelevant distractors. The term Attentional Blink (AB) denotes a transient impairment of awareness for the second of these two target items when presented close in time. Experimental studies reported that the AB is reduced when the second target is emotionally significant, suggesting a modulation of attention allocation. The aim of the present study was to systematically investigate the influence of target-distractor similarity on AB magnitude for faces with emotional expressions under conditions of limited attention in a series of six rapid serial visual presentation experiments. The task on the first target was either to discriminate the gender of a neutral face (Experiments 1, 3–6) or an indoor/outdoor visual scene (Experiment 2). The task on the second target required either the detection of emotional expressions (Experiments 1–5) or the detection of a face (Experiment 6). The AB was minimal or absent when targets could be easily discriminated from each other. Three successive experiments revealed that insufficient masking and target-distractor similarity could account for the observed immunity of faces against the AB in the first two experiments. An AB was present but not increased when the facial expression was irrelevant to the task suggesting that target-distractor similarity plays a more important role in eliciting an AB than the attentional set demanded by the specific task. In line with previous work, emotional faces were less affected by the AB.