Hippocampal Threat Reactivity Interacts with Physiological Arousal to Predict PTSD Symptoms

Prior studies highlighthow threat-related arousal may impair hippocampal function. Hippocampal impairments are reliably associated with post-traumatic stress disorder(PTSD); however, little research has characterized how increased threat-sensitivity may drive arousal responses to alter hippocampal reactivity, and further how these alterationsrelate to the sequelae of trauma-related symptoms. In a sample of individualsrecently exposed to trauma(N=117, 76 Female), we found that PTSD symptoms at 2-weeks and 3-months were associated with decreased hippocampal responses to threatas assessed with functional magnetic resonance imaging(fMRI).

 

Further, decreased hippocampal threat sensitivity was predicted by individual differences in fear-potentiated startle, an arousal-mediated behavior. Critically, the relationship betweenhippocampal threat sensitivity andPTSD symptomology only emerged inindividuals who showed high threat-related arousal. Collectively, ourfinding suggests thatdevelopment of PTSD is associated with threat-related decreases in hippocampal function, due to increases in fear-potentiated arousal.

 

Reference: 
Büşra O. Tanriverdi, David F. Gregory, Timothy D. Ely BA, Nathaniel G. Harnett PhD, Sanne J. H. van Rooij PhD, Lauren A.M. Lebois PhD, Antonia V. Seligowski PhD, Tanja Jovanovic PhD, Kerry J. Ressler MD, PhD, Stacey L. House MD, PhD, Francesca L. Beaudoin MD, PhD, Xinming An PhD, Thomas C. Neylan MD, Gari D. Clifford DPhil, Sarah D. Linnstaedt PhD, Laura T. Germine PhD, Kenneth A. Bollen PhD, Scott L. Rauch MD, John P. Haran MD, PhD, Alan B. Storrow MD, Christopher Lewandowski MD, Paul I. Musey Jr. MD, Phyllis L. Hendry MD, Sophia Sheikh MD, Christopher W. Jones MD, Brittany E. Punches PhD, RN, Michael C. Kurz MD, Meghan E. McGrath MD, Lauren A. Hudak MD, MPH, Jose L. Pascual MD, PhD, Mark J. Seamon MD, Elizabeth M. Datner MD, Claire Pearson MD, Robert M. Domeier MD, Niels K. Rathlev MD, Brian J. O'Neil MD, Leon D. Sanchez MD, MPH, Steven E. Bruce PhD, Mark W. Miller PhD, Robert H. Pietrzak PhD, MPH, Jutta Joormann PhD, Deanna M. Barch PhD, Diego A. Pizzagalli PhD, John F. Sheridan PhD, Jordan W. Smoller MD, Steven E. HartePhD, James M. Elliott PhD, Samuel A. McLean MD, MPH, Ronald C. Kessler PhD, Karestan C. Koenen PhD, Jennifer S. Stevens PhD, Vishnu P.Murty PhD | 2022
In: Journal of Neuroscience : ISSN: 1529-2401 | 42 | august | 6593-6604
https://doi.org/10.1523/JNEUROSCI.0911-21.2022
Keywords: 
Anxiety Symptoms, Arousal, Depressive Symptoms, Hippocampus, Neurophysiology, Posttraumatic Stress Disorder, Predictors, Psychotrauma, PTSD (en)