Jeong H, Park S, Dager SR, Lim SM, Lee SL, Hong H, Ma J, Ha E, Hong YS, Kang I, Lee EH, Yoon S, Kim JE, Kim J, Lyoo IK. Br. J. Psychiatry 2019; 214(6): 347-353.
Affiliation
Director,Ewha Brain Institute and Professor,Graduate School of Pharmaceutical Sciences and Department of Brain and Cognitive Sciences,Ewha Womans University,South Korea and Department of Psychiatry,University of Utah,US.
BACKGROUND: Firefighters are routinely exposed to various traumatic events and often experience a range of trauma-related symptoms. Although these repeated traumatic exposures rarely progress to the development of post-traumatic stress disorder, firefighters are still considered to be a vulnerable population with regard to trauma.AimsTo investigate how the human brain responds to or compensates for the repeated experience of traumatic stress.
METHOD: We included 98 healthy firefighters with repeated traumatic experiences but without any diagnosis of mental illness and 98 non-firefighter healthy individuals without any history of trauma. Functional connectivity within the fear circuitry, which consists of the dorsal anterior cingulate cortex, insula, amygdala, hippocampus and ventromedial prefrontal cortex (vmPFC), was examined using resting-state functional magnetic resonance imaging. Trauma-related symptoms were evaluated using the Impact of Event Scale - Revised.
RESULTS: The firefighter group had greater functional connectivity between the insula and several regions of the fear circuitry including the bilateral amygdalae, bilateral hippocampi and vmPFC as compared with healthy individuals. In the firefighter group, stronger insula-amygdala connectivity was associated with greater severity of trauma-related symptoms (β = 0.36, P = 0.005), whereas higher insula-vmPFC connectivity was related to milder symptoms in response to repeated trauma (β = -0.28, P = 0.01).
CONCLUSIONS: The current findings suggest an active involvement of insular functional connectivity in response to repeated traumatic stress. Functional connectivity of the insula in relation to the amygdala and vmPFC may be potential pathways that underlie the risk for and resilience to repeated traumatic stress, respectively.Declaration of interestNone.
Language: en
Keywords
Firefighter; fear network; functional connectivity; functional magnetic resonance imaging; post-traumatic stress disorder