Cognitive correlates of hypothalamic-pituitary-adrenal axis in major depression

The Hypothalamus-Pituitary-Adrenal Axis and Social Cognition in Borderline Personality Disorder

Borderline personality disorder (BPD) is characterized by emotional instability, impulsivity and unstable interpersonal relationships. Patients experience discomforting levels of distress, inducing symptoms like dissociation, aggression or withdrawal. Social situations are particularly challenging, and acute social stress can reduce patients' cognitive and social functioning. In patients with Major Depressive Disorder or Posttraumatic Stress Disorder, which show high comorbidity with BPD, the endocrine stress response is characterized by Hypothalamus-Pituitary-Adrenal (HPA) axis dysfunction, which affects cognitive functioning. Compared to these clinical groups, research on HPA-axis function in BPD is relatively scarce, but evidence points towards a blunted cortisol reactivity to acute stress. Since BPD patients are particularly prone to social stress and experience high subjective difficulties in these situations, it seems plausible that HPA-axis dysregulation might contribute to decreased social cognition in BPD. The present review summarizes findings on the HPA-axis function in BPD and its association with social cognition following acute social stress. For this purpose, we review literature that employed a widely used social stressor (Trier Social Stress Test, TSST) to study the effects of acute social stress on social cognition and the HPA-axis response. We contrast these findings with studies on social cognition that employed Cyberball, another widely used social stressor that lacks HPA-axis involvement. We conclude that research on social cognition in BPD reveals heterogeneous results with no clear relationship between social functioning and HPA-axis response. More research is needed to better understand the psychophysiological underpinnings of impaired social cognition in BPD.

Effectiveness of electrical vestibular nerve stimulation as adjunctive therapy to improve the cognitive functions in patients with Parkinson's disease

OBJECTIVES

The present study was undertaken to observe the effectiveness of electrical vestibular stimulation in improving cognitive functions in patients with Parkinson's disease.

METHODS

Randomized controlled trial (ClinicalTrials.gov Identifier: NCT04450550). 30 cases of PD, including both males and females were recruited in the study by convenient sampling after obtaining written informed consent. After recruiting, the participants were randomly assigned into two groups. The control group (n=15) received placebo stimulation whereas the intervention group (n=15) received electrical vestibular stimulation administered for 12 weeks. Auditory, visual reaction time and spatial and verbal memory were recorded before and after 6 weeks and after 12 weeks of intervention and compared.

RESULTS

There was a significant improvement in both auditory and visual reaction time of right and left-hand responses. Also, significant improvement was observed in both the spatial and verbal memory of the patients.

CONCLUSIONS

There was a significant improvement in the auditory and visual reaction time and spatial and verbal memory in the participants after the electrical vestibular nerve stimulation administration. No side effects were reported by the study participants and they have expressed willingness to continue the intervention after the study period also. The study recommends further detailed studies with a higher sample size to adopt electrical vestibular nerve stimulation as adjunctive therapy in the management of Parkinson's disease.

Attentional bias in individuals with depression and adverse childhood experiences: influence of the noradrenergic system?

RATIONALE

Major depressive disorder (MDD) is a severe mental disorder with affective, cognitive, and somatic symptoms. Mood congruent cognitive biases, including a negative attentional bias, are important for development, maintenance, and recurrence of depressive symptoms. MDD is associated with maladaptive changes in the biological stress systems such as dysregulations of central noradrenergic alpha2-receptors in the locus coeruleus-noradrenergic system, which can affect cognitive processes including attention. Patients with adverse childhood experiences (ACE), representing severe stress experiences in early life, might be particularly affected.

OBJECTIVES

With an experimental design, we aimed to gain further knowledge about the role of noradrenergic activity for attentional bias in MDD patients with and without ACE.

METHODS

We tested the effect of increased noradrenergic activity induced by the alpha2-receptor blocker yohimbine on attentional bias in a placebo-controlled repeated measures design. Four groups were included as follows: MDD patients with and without ACE, and healthy participants with and without ACE (total N = 128, all without antidepressant medication).

RESULTS

A significant effect of MDD on attentional bias scores of sad face pictures (p = .037) indicated a facilitated attentional processing of sad face pictures in MDD patients (compared to non-MDD individuals). However, we found no such effect of ACE. For attentional bias of happy face pictures, we found no significant effects of MDD and ACE. Even though a higher increase of blood pressure and salivary alpha-amylase following yohimbine compared to placebo indicated successful noradrenergic stimulation, we found no significant effects of yohimbine on attentional bias of happy or sad face pictures.

CONCLUSIONS

Our results are consistent with the hypothesis of a negative attentional bias in MDD patients. However, as we found no effect of ACE or yohimbine, further research is needed to understand the mechanisms by which ACE increases the risk of MDD and to understand the biological basis of the MDD-related negative attentional bias.

Atypical lateralization in neurodevelopmental and psychiatric disorders: What is the role of stress?

Hemispheric asymmetries are a major organizational principle of the human brain. In different neurodevelopmental and psychiatric disorders, like schizophrenia, autism spectrum disorders, depression, dyslexia and posttraumatic stress disorder, functional and/or structural hemispheric asymmetries are altered compared to healthy controls. The question, why these disorders all share the common characteristic of altered hemispheric asymmetries despite vastly different etiologies and symptoms remains one of the unsolved mysteries of laterality research. This review is aimed at reviewing potential reasons for why atypical lateralization is so common in many neurodevelopmental and psychiatric disorders. To this end, we review the evidence for overlaps in the genetic and non-genetic factors involved in the ontogenesis of different disorders and hemispheric asymmetries. While there is evidence for genetic overlap between different disorders, only few asymmetry-related loci have also been linked to disorders and importantly, those effects are mostly specific to single disorders. However, there is evidence for shared non-genetic influences between disorders and hemispheric asymmetries. Most neurodevelopmental and psychiatric disorders show alterations in the hypothalamic-pituitary adrenocortical (HPA) axis and maternal as well as early life stress have been implicated in their etiology. Stress has also been suggested to affect hemispheric asymmetries. We propose a model in which early life stress as well as chronic stress not only increases the risk for psychiatric and neurodevelopmental disorders but also changes structural and functional hemispheric asymmetries leading to the aberrant lateralization patterns seen in these disorders. Thus, pathology-related changes in hemispheric asymmetries are not a factor causing disorders, but rather a different phenotype that is affected by partly overlapping ontogenetic factors, primarily stress.

Psychobiological factors of resilience and depression in late life

In contrast to traditional perspectives of resilience as a stable, trait-like characteristic, resilience is now recognized as a multidimentional, dynamic capacity influenced by life-long interactions between internal and environmental resources. We review psychosocial and neurobiological factors associated with resilience to late-life depression (LLD). Recent research has identified both psychosocial characteristics associated with elevated LLD risk (e.g., insecure attachment, neuroticism) and psychosocial processes that may be useful intervention targets (e.g., self-efficacy, sense of purpose, coping behaviors, social support). Psychobiological factors include a variety of endocrine, genetic, inflammatory, metabolic, neural, and cardiovascular processes that bidirectionally interact to affect risk for LLD onset and course of illness. Several resilience-enhancing intervention modalities show promise for the prevention and treatment of LLD, including cognitive/psychological or mind-body (positive psychology; psychotherapy; heart rate variability biofeedback; meditation), movement-based (aerobic exercise; yoga; tai chi), and biological approaches (pharmacotherapy, electroconvulsive therapy). Additional research is needed to further elucidate psychosocial and biological factors that affect risk and course of LLD. In addition, research to identify psychobiological factors predicting differential treatment response to various interventions will be essential to the development of more individualized and effective approaches to the prevention and treatment of LLD.

Hair cortisol and childhood trauma predict psychological therapy response in depression and anxiety disorders

OBJECTIVE

Around 30-50% of patients with depression and anxiety disorders fail to respond to standard psychological therapy. Given that cortisol affects cognition, patients with altered hypothalamic-pituitary-adrenal (HPA) axis functioning may benefit less from such treatments. To investigate this, reliable pretreatment cortisol measures are needed.

METHOD

N = 89 outpatients with depression and anxiety disorders were recruited before undergoing therapy within an Improving Access to Psychological Therapies (IAPT) service. Three-month hair cortisol was determined, and the Childhood Trauma Questionnaire was administered. Patients were classified as responders if they showed significant decreases in depression (>= 6 points on the Patient Health Questionnaire) or anxiety (>= 5 points on the Generalised Anxiety Disorder Scale).

RESULTS

Non-responders in terms of depression (57%) had lower pretreatment hair cortisol concentrations (P = 0.041) and reported more physical abuse (P = 0.024), sexual abuse (P = 0.010) and total trauma (P = 0.039) when compared to responders. Non-responders in terms of anxiety (48%) had lower pretreatment hair cortisol (P = 0.027), as well as higher levels of emotional abuse (P = 0.034), physical abuse (P = 0.042) and total trauma (P = 0.048).

CONCLUSION

If future research confirms hair cortisol to be a predictor of psychological therapy response, this may prove a useful clinical biomarker which identifies a subgroup requiring more intensive treatment.

Neurobiological mechanisms of exercise and psychotherapy in depression: The SPeED study-Rationale, design, and methodological issues

BACKGROUND/AIMS

Even though cognitive behavioral therapy has become a relatively effective treatment for major depressive disorder and cognitive behavioral therapy-related changes of dysfunctional neural activations were shown in recent studies, remission rates still remain at an insufficient level. Therefore, the implementation of effective augmentation strategies is needed. In recent meta-analyses, exercise therapy (especially endurance exercise) was reported to be an effective intervention in major depressive disorder. Despite these findings, underlying mechanisms of the antidepressant effect of exercise especially in combination with cognitive behavioral therapy have rarely been studied to date and an investigation of its neural underpinnings is lacking. A better understanding of the psychological and neural mechanisms of exercise and cognitive behavioral therapy would be important for developing optimal treatment strategies in depression. The SPeED study (Sport/Exercise Therapy and Psychotherapy-evaluating treatment Effects in Depressive patients) is a randomized controlled trial to investigate underlying physiological, neurobiological, and psychological mechanisms of the augmentation of cognitive behavioral therapy with endurance exercise. It is investigated if a preceding endurance exercise program will enhance the effect of a subsequent cognitive behavioral therapy.

METHODS

This study will include 105 patients diagnosed with a mild or moderate depressive episode according to the Diagnostic and Statistical Manual of Mental Disorders (4th ed.). The participants are randomized into one of three groups: a high-intensive or a low-intensive endurance exercise group or a waiting list control group. After the exercise program/waiting period, all patients receive an outpatient cognitive behavioral therapy treatment according to a standardized therapy manual. At four measurement points, major depressive disorder symptoms (Beck Depression Inventory, Hamilton Rating Scale for Depression), (neuro)biological measures (neural activations during working memory, monetary incentive delay task, and emotion regulation, as well as cortisol levels and brain-derived neurotrophic factor), neuropsychological test performance, and questionnaires (psychological needs, self-efficacy, and quality of life) are assessed.

RESULTS

In this article, we report the design of the SPeED study and refer to important methodological issues such as including both high- and low-intensity endurance exercise groups to allow the investigation of dose-response effects and physiological components of the therapy effects.

CONCLUSION

The main aims of this research project are to study effects of endurance exercise and cognitive behavioral therapy on depressive symptoms and to investigate underlying physiological and neurobiological mechanisms of these effects. Results may provide important implications for the development of effective treatment strategies in major depressive disorder, specifically concerning the augmentation of cognitive behavioral therapy by endurance exercise.

Effects of cortisol on the memory bias for emotional words? A study in patients with depression and healthy participants using the Directed Forgetting task

Mood congruent alterations in information processing such as an impaired memory bias for emotional information and impaired inhibitory functions are prominent features of a major depressive disorder (MDD). Furthermore, in MDD patients hypothalamic-pituitary-adrenal axis dysfunctions are frequently found. Impairing effects of stress or cortisol administration on memory retrieval as well as impairing stress effects on cognitive inhibition are well documented in healthy participants. In MDD patients, no effect of acute cortisol administration on memory retrieval was found. The current study investigated the effect of acute cortisol administration on memory bias in MDD patients (N = 55) and healthy controls (N = 63) using the Directed Forgetting (DF) task with positive, negative and neutral words in a placebo controlled, double blind design. After oral administration of 10 mg hydrocortisone/placebo, the item method of the DF task was conducted. Memory performance was tested with a free recall test. Cortisol was not found to have an effect on the results of the DF task. Interestingly, there was significant impact of valence: both groups showed the highest DF score for positive words and remembered significantly more positive words that were supposed to be remembered and significantly more negative words that were supposed to be forgotten. In general, healthy participants remembered more words than the depressed patients. Still, the depressed patients were able to inhibit intentionally irrelevant information at a comparable level as the healthy controls. These results demonstrate the importance to distinguish in experimental designs between different cognitive domains such as inhibition and memory in our study.

Cortisol as a predictor of psychological therapy response in depressive disorders: systematic review and meta-analysis

BACKGROUND

Many patients with depressive disorders demonstrate resistance to psychological therapy. A frequent finding is hypothalamic-pituitary-adrenal (HPA) axis alterations. As cortisol is known to modulate cognitive processes, those patients may be less likely to profit from psychological therapy.

AIMS

To conduct a systematic review and meta-analysis on cortisol as a predictor of psychological therapy response.

METHOD

The Cochrane Library, EMBASE, MEDLINE and PsycINFO databases were searched. Records were included if they looked at patients with any depressive disorder engaging in psychological therapy, with a pre-treatment cortisol and a post-treatment symptom measure.

RESULTS

Eight articles satisfied our selection criteria. The higher the cortisol levels before starting psychological therapy, the more symptoms patients with depression experienced at the end of treatment and/or the smaller their symptom change.

CONCLUSIONS

Our findings suggest that patients with depression with elevated HPA functioning are less responsive to psychological therapy.

Stress and Memory: A Selective Review on Recent Developments in the Understanding of Stress Hormone Effects on Memory and Their Clinical Relevance

Stress causes a neuroendocrine response cascade, leading to the release of catecholamines and glucocorticoids (GCs). GCs influence learning and memory by acting on mineralocorticoid (MR) and glucocorticoid (GR) receptors. Typically, GCs enhance the consolidation of memory processing at the same time as impairing the retrieval of memory of emotionally arousing experiences. The present selective review addresses four recent developments in this area. First, the role of the endocannabinoid system in mediating the rapid, nongenomic effects of GCs on memory is illustrated in rodents. Subsequently, studies on the impact of the selective stimulation of MRs on different memory processes in humans are summarised. Next, a series of human experiments on the impact of stress or GC treatment on fear extinction and fear reconsolidation is presented. Finally, the clinical relevance of the effects of exogenous GC administration is highlighted by the description of patients with anxiety disorders who demonstrate an enhancement of extinction-based therapies by GC treatment. The review highlights the substantial progress made in our mechanistic understanding of the memory-modulating properties of GCs, as well as their clinical potential.

Effects of basal and acute cortisol on cognitive flexibility in an emotional task switching paradigm in men

The stress hormone cortisol is assumed to influence cognitive functions. While cortisol-induced alterations of declarative memory in particular are well-investigated, considerably less is known about its influence on executive functions. Moreover, most research has been focused on slow effects, and rapid non-genomic effects have not been studied. The present study sought to investigate the impact of acute cortisol administration as well as basal cortisol levels on cognitive flexibility, a core executive function, within the non-genomic time frame. Thirty-eight healthy male participants were randomly assigned to intravenously receive either cortisol or a placebo before performing a task switching paradigm with happy and angry faces as stimuli. Cortisol levels were measured at six points during the experiment. Additionally, before the experiment, basal cortisol measures for the cortisol awakening response were collected on three consecutive weekdays immediately following awakening and 30, 45, and 60min after. First and foremost, results showed a pronounced impact of acute and basal cortisol on reaction time switch costs, particularly for angry faces. In the placebo group, low basal cortisol was associated with minimal switch costs, whereas high basal cortisol was related to maximal switch costs. In contrast, after cortisol injection, basal cortisol levels showed no impact. These results show that cognitive flexibility-enhancing effects of acute cortisol administration are only seen in men with high basal cortisol levels. This result supports the context dependency of cortisol administration and shows the relevance of taking basal cortisol levels into account.

Effects of cortisol on cognition in major depressive disorder, posttraumatic stress disorder and borderline personality disorder - 2014 Curt Richter Award Winner

Stress hormones influence a wide range of cognitive functions, including memory performance and executive function. It is well established that glucocorticoids enhance memory consolidation but impair memory retrieval. While most of the effects have been attributed to glucocorticoid receptors (GR), the importance of mineralocorticoid receptors (MR) has been also emphasized. Dysfunctions in hypothalamic-pituitary-adrenal (HPA) axis have been reported for several mental disorders. While major depressive disorder (MDD) as well as borderline personality disorder (BPD) seem to be characterized by enhanced cortisol release in concert with a reduced feedback sensitivity of the HPA axis, in posttraumatic stress disorder (PTSD) a contrary picture has been reported. Despite the fact that altered GR function has been discussed for these disorders only very few studies have investigated the effects of glucocorticoids on cognitive performance in these patients so far. In a series of studies, we investigated the effects of glucocorticoids on cognition (i.e. declarative memory, working memory and response inhibition) in different mental disorders such as MDD, PTSD and BPD. While in patients with MDD cortisol administration failed to effect memory retrieval, patients with PTSD and BPD showed enhanced rather than impaired memory retrieval after cortisol administration. These results indicate an altered sensitivity to cortisol in these disorders. Results from one of our recent studies in the field of social cognition underline the importance of the MR. We found that emotional empathy was enhanced through stimulation of the MR via fludrocortisone in healthy participants and women with BPD. This review aims to integrate these findings and discuss potential mechanisms and implications.

Effects of acute cortisol administration on response inhibition in patients with major depression and healthy controls

Glucocorticoids (GCs) have repeatedly been shown to impair hippocampus-mediated, declarative memory retrieval and prefrontal cortex-based working memory in healthy subjects. However, recent experimental studies indicated that patients with major depressive disorder (MDD) lack these impairing effects. These missing effects have been suggested to result from dysfunctional brain GC receptors. The purpose of the present study was to investigate whether response inhibition, an executive function relying on the integrity of the prefrontal cortex, would be impaired after cortisol administration in patients with MDD. In a placebo-controlled, double blind crossover study, 50 inpatients with MDD and 54 healthy control participants conducted an emotional go/no-go task consisting of human face stimuli (fearful, happy, and neutral) after receiving a dose of 10 mg hydrocortisone and after placebo. GC administration had an enhancing effect on inhibitory performance in healthy control participants, indicated by faster responses, while no GC effect was revealed for the patients group. Moreover, patients showed an overall worse performance than healthy participants. In conclusion, this study further supports the hypothesis of impaired central glucocorticoid receptor function in MDD patients. Regarding the importance of inhibitory functioning for daily living, further studies are needed to examine the impact of glucocorticoids on response inhibition.

Effects of noradrenergic stimulation on memory in patients with major depressive disorder

Major depressive disorder (MDD) has been associated with alterations in the noradrenergic system and impaired memory function. In turn, enhanced memory function has been associated with noradrenergic stimulation. In this study, we examined whether noradrenergic stimulation would differentially improve memory function in patients with MDD and healthy controls. In a placebo-controlled crossover study, 20 patients with MDD and 18 age- and sex-matched healthy controls received either placebo or 5 mg of yohimbine, an alpha-2-adrenoceptor antagonist that causes increased noradrenergic activity, orally before memory testing. A word list paradigm was used to test memory consolidation. Furthermore, the autobiographical memory test assessing memory retrieval and a working memory test were administered. Salivary alpha-amylase and blood pressure were measured. Yohimbine improved memory consolidation (word list learning) across groups (main effect of yohimbine: p = 0.05). This effect was more prominent in depressed patients compared with controls (post hoc t-test: MDD p = 0.01, controls p = 0.77). Memory retrieval (autobiographical memory specificity) and working memory were not affected by yohimbine. Across groups, yohimbine administration resulted in an increase in blood pressure and alpha-amylase. In sum, these results further support the hypothesis that noradrenergic stimulation enhances memory consolidation. The mechanism by which yohimbine leads to stronger memory consolidation in depressed patients compared with healthy controls remains to be elucidated.

Associations of childhood trauma with hypothalamic-pituitary-adrenal function in borderline personality disorder and major depression

BACKGROUND

Alterations of the hypothalamus-pituitary-adrenal (HPA) axis are hallmarks in major depressive disorder (MDD) and there is some evidence about similar patterns in borderline personality disorder (BPD). This study examines HPA axis abnormalities with respect to clinical characteristics in both BPD (n=24) and MDD patients (n=33) as well as in healthy control participants (n=41).

METHOD

A 0.5mg dexamethasone suppression test was administered to evaluate basal cortisol release and HPA feedback sensitivity via salivary cortisol. Traumatic experiences in childhood as well as severity of borderline and depressive symptom severity and dissociation were obtained by self-report questionnaires.

RESULTS

Compared to the healthy control group, BPD and MDD patients exhibited both enhanced cortisol concentrations before and after the administration of 0.5mg dexamethasone. Higher cortisol levels were positively correlated to a history of childhood trauma, current dissociative symptoms and severity of borderline and depressive symptoms. Regression analyses revealed that some aspects of early trauma were associated with cortisol release before and after dexamethasone, whereas psychopathology did not contribute to the regression model.

CONCLUSIONS

HPA dysfunctions appear to be related rather to childhood trauma than to psychopathology in adulthood. Exposure to childhood trauma may contribute to long-lasting alterations in HPA activity and might enhance the risk for the development of later mental disorder.

Does depression impact cognitive impairment in patients with heart failure?

Prevalence studies have noted the cooccurrence of cognitive decline and depression in persons with heart failure. Cognitive impairment is associated with significant mortality and deteriorated quality of life, likely due to impairments in memory and executive function, which impact a patient's ability to understand and comply with prescribed treatment plans. This is especially true in complex diseases such as heart failure. Evidence from literature supports the possibility of a pathophysiological relationship between cognitive impairment, depression, and heart failure. Yet, very few studies have sought to investigate this relationship. This paper reviews current literature on the association between depression and cognitive impairment in persons with heart failure and explores possible mechanisms explaining this complex triad.

Cortisol has enhancing, rather than impairing effects on memory retrieval in PTSD

BACKGROUND

In the present study, we aimed to compare the effect of exogenous cortisol on memory retrieval in posttraumatic stress disorder (PTSD) with the effects in healthy controls. In healthy participants, administration of cortisol impairs declarative memory retrieval. Only a few studies have investigated these effects in PTSD yielding mixed results.

METHODS

In a placebo-controlled crossover study, 44 patients with PTSD and 65 healthy controls received either placebo or 10mg of hydrocortisone orally before memory testing. In addition to declarative memory retrieval (word list learning), we also tested autobiographical memory retrieval specificity.

RESULTS

In both tasks opposing effects of cortisol on memory were observed when comparing patients with controls. In controls, cortisol had impairing effects on memory retrieval, while in PTSD patients cortisol had enhancing effects on memory retrieval in both memory domains.

CONCLUSIONS

The present results suggest beneficial effects of acute cortisol elevations on hippocampal mediated memory processes in PTSD. Possible neurobiological mechanisms underlying these findings are discussed.