TY - JOUR
T1 - White matter microstructure of the uncinate fasciculus is associated with subthreshold posttraumatic stress disorder symptoms and fear potentiated startle during early extinction in recently deployed Service Members
AU - Costanzo, Michelle E.
AU - Jovanovic, Tanja
AU - Pham, Dzung
AU - Leaman, Suzanne
AU - Highland, Krista B.
AU - Norrholm, Seth Davin
AU - Roy, Michael J.
N1 - Funding Information:
This research was supported by a grant from the Center for Neuroscience and Regenerative Medicine (CNRM) and Henry M. Jackson Foundation for the Advancement of Military Medicine. Any opinions or assertions expressed are solely those of the authors and do not necessarily represent those of Uniformed Services University , the U.S. Army , U.S. Navy , Department of Defense , or the U.S. Government . There are no financial contributions, dual commitments or other potential conflicts of interest.
Publisher Copyright:
© 2016.
PY - 2016/4/8
Y1 - 2016/4/8
N2 - Early intervention following combat deployment has the potential to prevent posttraumatic stress disorder (PTSD), but there is a need for greater understanding of the factors that contribute to PTSD symptom progression. This study investigated: (1) fear-potentiated startle during a fear extinction, (2) white matter microstructure, and (3) PTSD symptom severity, in 48 recently deployed service members (SMs) who did not have sufficient PTSD symptoms to meet criteria for a clinical diagnosis. Electromyography startle during a conditional discrimination paradigm, diffusion tensor imaging, and the Clinician Administered PTSD Scale were assessed in a cohort of SMs within 2 months after their return from Iraq or Afghanistan. Significant correlations were found between left uncinate fasciculus (UF) white matter tract integrity and total PTSD symptoms, r = -0.343, p = 0.018; the left UF and hyperarousal symptoms, r = -0.29, p = 0.047; right UF integrity and total PTSD symptoms r = -0.3371, p = 0.01; right UF integrity and hyperarousal symptoms r = -0.332, p = 0.023; left UF and startle during early extinction, r = .31, p = 0.033. Our results indicate that compromise of UF tract frontal-limbic connections are associated with greater PTSD symptom severity and lower startle response during extinction. In a subthreshold population, such a relationship between brain structure, physiological reactivity, and behavioral expression may reveal vulnerabilities that could have significant implications for PTSD symptom development.
AB - Early intervention following combat deployment has the potential to prevent posttraumatic stress disorder (PTSD), but there is a need for greater understanding of the factors that contribute to PTSD symptom progression. This study investigated: (1) fear-potentiated startle during a fear extinction, (2) white matter microstructure, and (3) PTSD symptom severity, in 48 recently deployed service members (SMs) who did not have sufficient PTSD symptoms to meet criteria for a clinical diagnosis. Electromyography startle during a conditional discrimination paradigm, diffusion tensor imaging, and the Clinician Administered PTSD Scale were assessed in a cohort of SMs within 2 months after their return from Iraq or Afghanistan. Significant correlations were found between left uncinate fasciculus (UF) white matter tract integrity and total PTSD symptoms, r = -0.343, p = 0.018; the left UF and hyperarousal symptoms, r = -0.29, p = 0.047; right UF integrity and total PTSD symptoms r = -0.3371, p = 0.01; right UF integrity and hyperarousal symptoms r = -0.332, p = 0.023; left UF and startle during early extinction, r = .31, p = 0.033. Our results indicate that compromise of UF tract frontal-limbic connections are associated with greater PTSD symptom severity and lower startle response during extinction. In a subthreshold population, such a relationship between brain structure, physiological reactivity, and behavioral expression may reveal vulnerabilities that could have significant implications for PTSD symptom development.
KW - Combat veterans
KW - Diffusion tensor imaging
KW - Fear-potentiated startle
KW - Subthreshold PTSD
UR - http://www.scopus.com/inward/record.url?scp=84959272727&partnerID=8YFLogxK
U2 - 10.1016/j.neulet.2016.02.041
DO - 10.1016/j.neulet.2016.02.041
M3 - Article
C2 - 26923670
AN - SCOPUS:84959272727
SN - 0304-3940
VL - 618
SP - 66
EP - 71
JO - Neuroscience Letters
JF - Neuroscience Letters
ER -