Effective Connectivity of Fear Circuitry and Emotion Regulation in Specific Phobia
2011 (English)Conference paper (Other academic)
Background: The aim of the present study was to characterize effective brain connectivity patterns in patients with specific phobia.
Methods: Sixteen patients with specific phobia were exposed to phobic and fear-relevant but non-phobic stimuli while regional cerebral blood flow was measured using [15O]-labelled water and positron emission tomography. Self reported state anxiety was also evaluated using the Spielberger State Anxiety Inventory (STAI-S). Different connectivity architectures were built based on five regions of interest (ROIs): the amygdala; subgenual anterior cingulate cortex (sACC) area 25; anterior midcingulate cortex (aMCC) area 24; insular cortex and dorsolateral prefrontal cortex (DLPFC) area 8. The ROIs were chosen based on their role in generating and attenuating fear. Structural equations modelling and Bayesian inference were used to assign probabilities to all possible architectures.
Results: Top ranking models reveal different connectivity patterns resulting from phobic and non-phobic exposure. When exposed to phobic stimuli sACC appear to be driving the network. In contrast, when exposed to non-phobic stimuli the DLPFC is more active and dampen amygdala activity. This could reflect successful reappraisal processes during non-phobic exposure. The DLPFC correlated negatively (r=-0.49) with STAI-S during non-phobic exposure, but not phobic exposure also suggesting that emotional regulation fails in phobia. No direct correlation between amygdala activity and STAI-S was evident during either phobic or non-phobic conditions.
Conclusions: These results suggest that emotional control processes operative when exposed to fear-relevant, but non-phobic cues are impaired during exposure to phobic stimuli.
Place, publisher, year, edition, pages
2011. Vol. 69
Research subject Psychology
IdentifiersURN: urn:nbn:se:uu:diva-163057OAI: oai:DiVA.org:uu-163057DiVA: diva2:462607
66th Annual Meeting of the Society of Biological Psychiatry, San Francisco, CA, MAY 12-14, 2011
Paper presentation2011-12-072011-12-072012-01-18Bibliographically approved