Faculty Bibliography

Recent evidence suggests that early life stress (ELS) changes stress reactivity via reduced resting state functional connectivity (rs-FC) between amygdala and the prefrontal cortex. Oxytocin (OXT) modulates amygdala connectivity and attenuates responses to psychosocial stress, but its effect appears to be moderated by ELS. Here we first investigate the effect of ELS on amygdala-prefrontal rs-FC, and examine whether ELS-associated changes of rs-FC in this neural circuit predict its response to psychosocial stress. Secondly, we explore the joint effect of OXT and ELS on the amygdala-prefrontal circuit. Eighteen healthy young males participated in a resting-state fMRI study of OXT effects using a double-blind, randomized, placebo-controlled, within-subject crossover design. We measured the rs-FC to bilateral amygdalae and subsequently assessed changes of state anxiety and prefrontal responses to psychosocial stress. Multiple linear regressions showed that ELS, specifically emotional abuse, predicted reduced rs-FC between the right amygdala and pregenual anterior cingulate cortex (pgACC), which in turn predicted elevated state anxiety after psychosocial stress. In subjects with lower ELS scores, stronger pgACC-amygdala rs-FC predicted stronger pgACC deactivation during the psychosocial stress task, and this rest-task interaction was attenuated by OXT. In subjects with higher ELS scores however, the rest-task interaction was altered and OXT showed no significant effect. These findings highlight that ELS reduces pgACC-amygdala rs-FC and alters how rs-FC of this circuit predicts its stress responsiveness. Such changes in pgACC-amygdala functional dynamics may underlie the altered sensitivity to the effects of OXT after ELS.

Heterogeneity in glucocorticoid response to experimental stress conditions has shown to differentiate individuals with healthy from maladaptive real-life stress responses in a number of distinct domains. However, it is not known if this heterogeneity influences the risk for developing stress related disorders or if it is a biological consequence of the stress response itself. Determining if glucocorticoid response to stress induction prospectively predicts psychological vulnerability to significant real life stressors can adjudicate this issue. To test this relationship, salivary cortisol as well as catecholamine responses to a laboratory stressor during academy training were examined as predictors of empirically identified distress trajectories through the subsequent 4 years of active duty among urban police officers routinely exposed to potentially traumatic events and routine life stressors (N = 234). During training, officers were exposed to a video vignette of police officers exposed to real-life trauma. Changes in salivary 3-methoxy-4-hydroxyphenylglycol (MHPG) and cortisol in response to this video challenge were examined as predictors of trajectory membership while controlling for age, gender, and baseline neuroendocrine levels. Officers who followed trajectories of resilience and recovery over 4 years mounted significant increases in cortisol in response to the experimental stressor, while those following a trajectory of chronic increasing distress had no significant cortisol change in response to the challenge. MHPG responses were not associated with distress trajectories. Cortisol response prospectively differentiated trajectories of distress response suggesting that a blunted cortisol response to a laboratory stressor is a risk factor for later vulnerability to distress following significant life stressors.

PURPOSE OF REVIEW/OBJECTIVE:The human circadian system creates and maintains cellular and systemic rhythmicity essential to homeostasis. Loss of circadian rhythmicity fundamentally affects the neuroendocrine, immune and autonomic system, similar to chronic stress and, thus, may play a central role in the development of stress-related disorders. This article focuses on the role of circadian misalignment in the pathophysiology of posttraumatic stress disorder (PTSD). RECENT FINDINGS/RESULTS:Sleep disruption is a core feature of PTSD supporting the important supraordinate pathophysiological role of circadian system in PTSD. Furthermore, direct and indirect human and animal PTSD research suggests circadian system linked neuroendocrine, immune, metabolic and autonomic dysregulation with blunted diurnal rhythms, specific sleep pattern pathologies and cognitive deficits, as well as endocannabinoid and neuropeptide Y system alterations and altered circadian gene expression, linking circadian misalignment to PTSD pathophysiology. SUMMARY/CONCLUSIONS:PTSD development is associated with chronodisruption findings. Evaluation and treatment of sleep and circadian disruption should be the first steps in PTSD management. State-of-the-art methods of circadian rhythm assessment should be applied to bridge the gap between clinical significance and limited understanding of the relationship between traumatic stress, sleep and circadian system.

The mineralocorticoid receptor (MR) is highly expressed in the hippocampus and prefrontal cortex. MR have an important role in appraisal processes and in modulating stress-associated emotional reactions but it is not known whether the MR affects empathy. Borderline personality disorder (BPD) is characterized by disturbed emotion regulation and alterations in empathy. In the current study, we examined whether stimulation of the MR enhances empathy in patients with BPD and healthy individuals. In a placebo-controlled study, we randomized 38 women with BPD and without psychotropic medication, and 35 healthy women to either placebo or 0.4 mg fludrocortisone, an MR agonist. Subsequently, all participants underwent two tests of social cognition, the Multifaceted Empathy Test (MET) and the Movie for the Assessment of Social Cognition (MASC), measuring cognitive and emotional facets of empathy. Eighteen BPD patients and 18 healthy women received placebo, whereas 20 BPD patients and 17 healthy women received fludrocortisone. In the MET, fludrocortisone enhanced emotional empathy across groups, whereas cognitive empathy was not affected. In the MASC, no effect of fludrocortisone could be revealed. In both tests, BPD patients and healthy women did not differ significantly in cognitive and emotional empathy and in their response to fludrocortisone. Stimulation of MR enhanced emotional empathy in healthy women and in BPD patients. Whether fludrocortisone might have a therapeutic role in psychotherapeutic processes, remains to be elucidated.

BACKGROUND:Dysregulations of the hypothalamic-pituitary-adrenal axis may impact inflammatory processes in post-traumatic stress disorder (PTSD), possibly resulting in a low-grade inflammation as reflected by elevated levels of C-reactive protein (CRP). METHODS:Serum CRP levels and salivary cortisol before and after the dexamethasone suppression test (DST) were assessed in 50 inpatients with main diagnoses PTSD, major depressive disorder or borderline personality disorder. RESULTS:A strong trend for lower CRP levels was found in PTSD positive individuals compared with patients without PTSD. CONCLUSIONS:Our study does not support the hypothesis of elevated serum CRP levels in PTSD compared with other psychiatric patients. However, a dysbalanced immune system with suppressed CRP might contribute to the elevated somatic comorbidity in PTSD.

Vulnerability-stress models implicate that alterations of the autonomous nervous system contribute to the development of psychosis. Previous research has found autonomic arousal alterations in psychotic disorders and at-risk individuals that are not explained by medication alone. To test whether these alterations are associated with the extent of an individual's vulnerability and whether they are specific to psychosis, we compared participants with psychosis (n=23), first-degree relatives of individuals with psychosis (n=21), and healthy participants with attenuated positive symptoms (n=23) to participants with depression (n=24) and healthy controls (n=24). At rest, skin conductance level was assessed and photoplethysmography was applied to measure time- and frequency-domain heart rate variability (HRV). Univariate and multivariate analyses of covariance with perceived stress and psychophysiological values as dependent variables showed significant between-group differences for perceived stress (p=.010), heart rate (p=.022), time-domain HRV indices (all ps≤.027), and vagal activity (p=.017). Group differences in sympathetic activity were nonsignificant (p=.069). In an additional analysis with medication as a second between-group factor, the physiological between-group differences remained significant or trend significant (all ps≤.060). With the exception of sympathetic activity, participants with psychosis exhibited more extreme arousal than the control groups. First-degree relatives and participants with attenuated symptoms showed comparable autonomic activity to healthy controls. Thus, the hypothesized association of an alteration of arousal and vulnerability to psychosis was not confirmed. However, particularly low time-domain HRV was found for psychosis, with significant differences to healthy controls (all ps≤.007) and to depression (all ps≤.004), with the latter indicating a specificity to psychosis.

The investigation of veridical mood-congruent memory (MCM) in major depressive disorder (MDD) has been subject of many studies, whereas mood-congruent false memory has received comparatively little attention. The present study examined the influence of valence, personal relevance and the valence of the context of the learning material on true and false MCM in 20 inpatients with MDD and 20 healthy controls. Sixty positive, negative, neutral or personally relevant nouns were either combined with a positive, negative or neutral adjective. Word pairs were presented to participants in a learning trial. In a recognition task, participants had to identify the previously studied word pairs. A MCM effect could not be found for hits. However, in exploratory analyses, word pairs containing personally relevant nouns were more rated towards old by the patient relative to the control group. Furthermore, depressed patients tended to rate items more towards old than controls when the words were presented in a negative new context. Results are in line with previous findings in depression research emphasizing the role of mood-congruent false memories for mood disorders.

OBJECTIVE:Patients with major depressive disorder (MDD) often suffer from impaired declarative, episodic and working memory. Further, MDD is associated with alterations in the noradrenergic system. There is evidence that presynaptic α2 receptors that inhibit release of noradrenaline are upregulated in MDD. Results from our recent study demonstrated that increasing noradrenergic activity by blocking the α2 receptor with yohimbine leads to stronger memory consolidation in MDD patients. In the current study, we further examined the role of noradrenaline on memory in MDD by administering clonidine that activates presynaptic α2 receptors and thereby globally suppresses the noradrenergic output. METHODS:In a placebo-controlled, within-subject crossover design, 20 patients with MDD and 20 healthy controls received either 0.15 mg of clonidine or placebo orally before memory testing. A word list paradigm (memory consolidation), an autobiographical memory test (retrieval) and a working memory test were applied. Salivary alpha-amylase and blood pressure were measured. RESULTS:Across groups, clonidine decreased blood pressure and alpha-amylase. Clonidine impaired memory consolidation (word list learning) in depressed patients and controls. Memory retrieval and working memory were not affected by clonidine. CONCLUSIONS:Reducing noradrenergic activity had a specific effect on memory consolidation in patients with MDD and healthy controls. The underlying mechanisms need further scrutiny.

Early life stress is said to play a critical role in the development of borderline personality disorder (BPD) and major depressive disorder (MDD), but the underlying mediating factors remain uncertain. This study aimed to investigate self-reported childhood trauma, emotion regulation difficulties, and their associations in a sample of BPD (n = 49) and MDD (n = 48) patients and healthy control participants (n = 63). Multiple regressions were used to evaluate the impact of the quality and severity of self-reported childhood trauma on self-reported emotion regulation. The results supported an association between self-reported maltreatment experiences, especially emotional abuse and neglect, and emotion regulation difficulties. Additional analyses showed that emotion regulation difficulties influence the association between self-reported emotional abuse and acute symptomatology in the BPD subgroup. Emotion regulation difficulties may be 1 pathway through which early life stress, particularly emotional abuse, increases the risk for developing BPD symptomatology.