Hippocampal Threat Reactivity Interacts with Physiological Arousal to Predict PTSD Symptoms

Abstract

Prior studies highlight how 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 alterations relate to the sequelae of trauma-related symptoms. In a sample of individuals recently 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 threat as 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 between hippocampal threat sensitivity and PTSD symptomology only emerged in individuals who showed high threat-related arousal. Collectively, our finding suggests that development of PTSD is associated with threat-related decreases in hippocampal function, due to increases in fear-potentiated arousal.

Development and validation of a risk prediction model for post-traumatic stress disorder symptoms in patients with acute myocardial infarction in China

“…A previous study has shown that the symptoms of PTSD in patients with AMI may be related to the patient's age, gender, and personality characteristics (8). Hippocampal damage, serum cortisol, C-reactive protein are predictors of PTSD symptoms (9)(10)(11). However, there are currently no guidelines or risk prediction models to guide clinical personnel in reducing or preventing PTSD symptoms in patients with AMI.…”