The impact of mindfulness meditation on fear load and fear inhibition : examining parasympathetic activation as an underlying mechanism

As demonstrated via fear-potentiated startle (FPS) paradigms, individuals with fear-based disorders exhibit greater startle responses and a lowered ability to distinguish between fear-related stimuli and safe stimuli (i.e., poor fear inhibition). Physiological indicators of self-regulation, such as respiratory sinus arrhythmia (RSA), appear to be related to the startle response. Therefore, increasing self-regulation may reduce fear load and improve fear inhibition. One method for doing so may be through mindfulness meditation. Using a FPS paradigm, the current study explored the use of mindfulness meditation (as compared to relaxation) as a method of decreasing fear load and enhancing fear inhibition by improving self-regulation (measured by RSA). Participants included 54 female undergraduates (Mage = 20.26) who completed several self-report questionnaires and then underwent the FPS paradigm. Results indicated that both groups exhibited similar increases in self-reported state mindfulness and decreases in tension. Contrary to hypotheses, membership in the relaxation condition predicted greater increase in RSA compared to the mindfulness condition. RSA mediated the relation between study condition and fear inhibition, but not fear load. Results may suggest that longer and/or more frequent mindfulness sessions may be necessary in order for positive effects on RSA to be observed. Limitations and future directions will be discussed

Prospective Associations between Emotion Dysregulation and Fear-Potentiated Startle: The Moderating Effect of Respiratory Sinus Arrhythmia

Background: Emotion dysregulation has been implicated in the negative outcomes following trauma exposure. A proposed biomarker of emotion dysregulation, respiratory sinus arrhythmia (RSA), has demonstrated associations with trauma-related phenomena, such as the fear-potentiated startle (FPS) response. The current study aimed to examine the prospective association between emotion dysregulation and RSA and FPS several years following trauma exposure. Methods: Participants were 131 women exposed to a campus mass shooting on February 14, 2008. Pre-shooting emotion dysregulation was assessed in 2006-2008. Startle response, measured by orbicularis oculi electromyography (EMG), and RSA were gathered during an FPS paradigm conducted from 2012-2015. Results: No significant associations among emotion dysregulation, RSA, and FPS emerged among the full sample. However, emotion dysregulation predicted FPS during both acquisition ( = .54, p = .03) and extinction ( = .75, p <.01), but only among individuals with high resting RSA. Conclusions: Findings suggest that pre-shooting emotion dysregulation is a potent predictor of FPS several years following potential trauma exposure, and this association varies by RSA level. Results emphasize the importance of examining autonomic regulation in the association between emotion dysregulation and recovery from trauma exposure

A prospective examination of sex differences in posttraumatic autonomic functioning

BACKGROUND: Cross-sectional studies have found that individuals with posttraumatic stress disorder (PTSD) exhibit deficits in autonomic functioning. While PTSD rates are twice as high in women compared to men, sex differences in autonomic functioning are relatively unknown among trauma-exposed populations. The current study used a prospective design to examine sex differences in posttraumatic autonomic functioning. METHODS: 192 participants were recruited from emergency departments following trauma exposure ( RESULTS: 2-week systolic BP was significantly higher in men, while 2-week HR was significantly higher in women, and a sex by PTSD interaction suggested that women who developed PTSD demonstrated the highest HR levels. Two-week HF-HRV was significantly lower in women, and a sex by PTSD interaction suggested that women with PTSD demonstrated the lowest HF-HRV levels. Skin conductance response in the emergency department was associated with 2-week HR and HF-HRV only among women who developed PTSD. CONCLUSIONS: Our results indicate that there are notable sex differences in autonomic functioning among trauma-exposed individuals. Differences in sympathetic biomarkers (BP and HR) may have implications for cardiovascular disease risk given that sympathetic arousal is a mechanism implicated in this risk among PTSD populations. Future research examining differential pathways between PTSD and cardiovascular risk among men versus women is warranted

Trauma-related emotions and radical acceptance in dialectical behavior therapy for posttraumatic stress disorder after childhood sexual abuse

Background: Posttraumatic Stress Disorder (PTSD) related to childhood sexual abuse (CSA) is often associated with a wide range of trauma-related aversive emotions such as fear, disgust, sadness, shame, guilt, and anger. Intense experience of aversive emotions in particular has been linked to higher psychopathology in trauma survivors. Most established psychosocial treatments aim to reduce avoidance of trauma-related memories and associated emotions. Interventions based on Dialectical Behavior Therapy (DBT) also foster radical acceptance of the traumatic event. Methods: This study compares individual ratings of trauma-related emotions and radical acceptance between the start and the end of DBT for PTSD (DBT-PTSD) related to CSA. We expected a decrease in trauma-related emotions and an increase in acceptance. In addition, we tested whether therapy response according to the Clinician Administered PTSD-Scale (CAPS) for the DSM-IV was associated with changes in trauma-related emotions and acceptance. The data was collected within a randomized controlled trial testing the efficacy of DBT-PTSD, and a subsample of 23 women was included in this secondary data analysis. Results: In a multilevel model, shame, guilt, disgust, distress, and fear decreased significantly from the start to the end of the therapy whereas radical acceptance increased. Therapy response measured with the CAPS was associated with change in trauma-related emotions. Conclusions: Trauma-related emotions and radical acceptance showed significant changes from the start to the end of DBT-PTSD. Future studies with larger sample sizes and control group designs are needed to test whether these changes are due to the treatment. Trial registration: ClinicalTrials.gov, number NCT0048100

The renin-angiotensin system in PTSD: a replication and extension.

Prior observational studies have suggested that medications targeting the renin-angiotensin system, such as angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin receptor blockers (ARBs), may be associated with decreased PTSD symptoms. Given known sex differences in PTSD prevalence and cardiovascular disease, here we tested whether the effects of ACE-I/ARB status on PTSD differ by sex. We also expanded these observations with replication analyses in a large biorepository database. Participants in the initial sample included 840 trauma-exposed individuals recruited as part of the Grady Trauma Project. The Modified PTSD Symptom Scale (M-PSS) was administered and ACE-I/ARB status was determined by self-report. Replication analyses were conducted using a large biorepository database (Partners Healthcare Biobank, N = 116,389) with diagnoses and medication status based on available electronic health records. Among individuals treated with ACE-Is/ARBs in the initial sample, women had significantly higher M-PSS total and Re-experiencing severity compared to men (ps &lt; 0.05). Analyses with the large biorepository sample robustly replicated the overall effects of ACE-I/ARB medication associated with lower rate of PTSD diagnosis (p &lt; 0.001). We also demonstrated that this effect may be specific to the renin-angiotensin system as it did not replicate for beta-blockers, calcium channel blockers, or diuretics. When we examined more specific drug classes, results indicated that the ACE-I/ARB effect on PTSD may be driven more by ARBs (e.g., Losartan) than by ACE-Is. Post-hoc analyses indicated that racial differences may exist in these effects. Overall, our results replicate and extend prior observations that the renin-angiotensin system is associated with PTSD. Medications targeting this system may be worthy of further investigation for PTSD treatment. Our findings suggest that sex and race effects should be considered in future treatment research