ABSTRACT
The core feature of separation anxiety is excessive distress when faced with actual or perceived separation from people to whom the individual has a strong emotional attachment. So far little is known about the neurobiological underpinnings of separation anxiety. Therefore, we investigated functional (amygdala responsiveness and functional connectivity during threat-related emotion processing) and structural (grey matter volume) imaging markers associated with separation anxiety as measured with the Relationship Scale Questionnaire in a large sample of healthy adults from the Münster Neuroimaging Cohort (N = 320). We used a robust emotional face-matching task and acquired high-resolution structural images for morphometric analyses using voxel-based morphometry. The main results were positive associations of separation anxiety scores with amygdala reactivity to emotional faces as well as increased amygdala grey matter volumes. A functional connectivity analysis revealed positive associations between separation anxiety and functional coupling of the amygdala with areas involved in visual processes and attention, including several occipital and somatosensory areas. Taken together, the results suggest a higher emotional involvement in subjects with separation anxiety while watching negative facial expressions, and potentially secondary neuro-structural adaptive processes. These results could help to understand and treat (adult) separation anxiety.
Subject(s)
Amygdala/pathology , Amygdala/physiopathology , Anxiety, Separation/pathology , Anxiety, Separation/physiopathology , Adult , Cohort Studies , Emotions , Facial Expression , Family Relations , Female , Gray Matter/pathology , Gray Matter/physiopathology , Humans , Magnetic Resonance Imaging , Male , Nerve Net/pathology , Nerve Net/physiopathology , Occipital Lobe/physiopathology , Somatosensory Cortex/physiopathology , Surveys and QuestionnairesABSTRACT
The fear of negative evaluation is one of the hallmark features of social anxiety. Behavioral evidence thus far largely supports cognitive models which postulate that information processing biases in the face of socially relevant information are a key factor underlying this widespread phobia. So far only one neuroimaging study has explicitly focused on the fear of negative evaluation in social anxiety where the brain responses of social phobics were compared to healthy participants during the processing of self-referential relative to other-referential criticism, praise or neutral information. Only self-referential criticism led to stronger activations in emotion-relevant regions of the brain, such as the amygdala and medial prefrontal cortices (mPFC), in the social phobics. The objective of the current study was to determine whether these findings could be extended to subclinical social anxiety. In doing so, the specificity of this self-referential bias was also examined by including both social and non-social (physical illness-related) threat information as well as a highly health anxious control group in the experimental paradigm. The fMRI findings indicated that the processing of emotional stimuli was accompanied by activations in the amygdala and the ventral mPFC, while self-referential processing was associated with activity in regions such as the mPFC, posterior cingulate and temporal poles. Despite the validation of the paradigm, the results revealed that the previously reported behavioral and brain biases associated with social phobia could not be unequivocally extended to subclinical social anxiety. The divergence between the findings is explored in detail with reference to paradigm differences and conceptual issues.