Networks of phobic fear: Functional connectivity shifts in two subtypes of specific phobia

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

Anxiety disorders can be conceptualized by an abnormal interplay of emotion-processing brain circuits; however, knowledge of brain connectivity measures in specific phobia is still limited. To explore functional interactions within selected fear-circuitry structures (anterior cingulate cortex (ACC), amygdala, insula), we re-examined three task-based fMRI studies using a symptom provocation approach (n = 94 subjects in total) on two different phobia subtypes (animal subtype as represented by snake phobia (SP) and blood-injection-injury subtype as represented by dental phobia (DP)), and a non-phobic healthy control group (HC). Functional connectivity (FC) analyses detected a negative coupling between the amygdala and the ACC in HC for both classes of phobic stimuli, while SP and DP lacked this inhibitory relationship during visual stimulus presentation. However, a negative FC between the insula and the amygdala was observed in DP during visual symptom provocation, which reversed to a positive FC under auditory symptom provocation pointing to effects depending on stimulus modality in DP. SP showed significantly higher FC towards snake-anxiety eliciting stimuli than HC on an average measure of FC, while DP showed a similar pattern under auditory stimulation only. These findings altogether indicate FC shifts during symptom provocation in specific phobia possibly reflecting impaired emotion regulation processes within fear-circuitry networks. FC hence could represent a prime target for neuroscience-informed augmentation strategies when treating pathological forms of fear.

Details

Original languageEnglish
Pages (from-to)167-172
Number of pages6
JournalNeuroscience letters
Volume662
Publication statusPublished - 1 Jan 2018
Peer-reviewedYes

External IDs

PubMed 29054435

Keywords

ASJC Scopus subject areas

Keywords

  • Amygdala, Anterior cingulate cortex, Fear regulation, Functional connectivity, Insula, Specific phobia