Psychobiological response to pain in female adolescents with nonsuicidal self-injury

Two-year course of non-suicidal self-injury in an adolescent clinical cohort: The role of childhood adversity in interaction with cortisol secretion

AIM

Non-suicidal self-injury (NSSI) is a highly prevalent phenomenon during adolescence. Nonetheless, research on predictors of the clinical course of NSSI over time is still scarce. The present study aimed at investigating the impact of adverse childhood experiences (ACE) and hypothalamus-pituitary-adrenal (HPA) axis functioning on the longitudinal course of NSSI.

METHODS

In a sample of n = 51 help-seeking adolescents engaging in NSSI, diurnal cortisol secretion (CAR, cortisol awakening response; DSL, diurnal slope), hair cortisol concentrations and ACE were assessed at baseline. Clinical outcome was defined by change in the frequency of NSSI in the past 6 months measured 12 and 24 months after the baseline assessments. Mixed-effects linear regression models were used to test for effects of ACE and HPA axis functioning on the course of NSSI.

RESULTS

ACE and HPA axis functioning did not show main but interaction effects in the prediction of NSSI frequency over time: Adolescents with a low severity of ACE and either an increased CAR or a flattened DSL showed a steep decline of NSSI frequency in the first year followed by a subsequent increase of NSSI frequency in the second year.

CONCLUSIONS

Our findings could be interpreted in the sense of high diurnal cortisol concentrations in the absence of ACE being favorable for clinical improvement on the short-term but bearing a risk of allostatic load and subsequent increase of NSSI frequency. In contrast, adolescents with severe ACE may benefit from elevated cortisol concentrations leading to slower but lasting decreases of NSSI frequency.

Pain sensitivity as a state marker and predictor for adolescent non-suicidal self-injury

BACKGROUND

The pain analgesia hypothesis suggests that reduced pain sensitivity (PS) is a specific risk factor for the engagement in non-suicidal self-injury (NSSI). Consistent with this, several studies found reduced PS in adults as well as adolescents with NSSI. Cross-sectional studies in adults with borderline personality disorder (BPD) suggest that PS may (partially) normalize after remission or reduction of BPD symptoms. The objective of the present study was to investigate the development of PS over 1 year in a sample of adolescents with NSSI and to investigate whether PS at baseline predicts longitudinal change in NSSI.

METHODS

N = 66 adolescents who underwent specialized treatment for NSSI disorder participated in baseline and 1-year follow-up assessments, including heat pain stimulation for the measurement of pain threshold and tolerance. Associations between PS and NSSI as well as BPD and depressive symptoms were examined using negative binomial, logistic, and linear regression analyses.

RESULTS

We found that a decrease in pain threshold over time was associated with reduced NSSI (incident rate ratio = 2.04, p = 0.047) and that higher pain tolerance at baseline predicted lower probability for NSSI (odds ratio = 0.42, p = 0.016) 1 year later. However, the latter effect did not survive Holm correction (p = 0.059). No associations between PS and BPD or depressive symptoms were observed.

CONCLUSION

Our findings suggest that pain threshold might normalize with a decrease in NSSI frequency and could thus serve as a state marker for NSSI.

Plasma Endocannabinoid Levels in Patients with Borderline Personality Disorder and Healthy Controls

Borderline personality disorder (BPD) is a highly prevalent psychiatric disorder and presents a complex therapeutic challenge due to limited treatment modalities. Recent focus has converged on the endocannabinoid system (ECS) as a prospective modulator of psychopathological processes in BPD. To address this hypothesis, we analysed plasma endocannabinoid concentrations, specifically anandamide (AEA) and 2-arachidonoylglycerol (2-AG), in a cohort of 49 female BPD patients and 32 matched healthy controls (HC). Additionally, we examined the effect of the FAAH polymorphism rs324420 and correlates with psychopathology. The results indicate heightened AEA levels and, by trend, augmented 2-AG levels within the patient group, as compared to the HC group. Significant between group differences in AEA levels were evident in the CC genotype (FAAH_rs324420) but not in A-allele carriers while the commonly observed difference in AEA levels between A-allele carriers as compared to the CC genotype was not evident in patients. An effect of genotype was found with higher ratings of depression (Beck's depression inventory, BDI-II) in the CC genotype compared to A-allele carriers (FAAH_rs32442), particularly in the patients. Significant alterations in AEA (and by trend in 2-AG) in patients with BPD may relate to compensatory ECS activity. The finding that the effect is most pronounced in CC homozygotes, might point towards a countermeasure to balance physiologically lower baseline AEA levels. The findings warrant further research to develop potentially beneficial psychopharmacological therapies.

Physiological stress reactivity and self-harm: A meta-analysis

OBJECTIVE

Self-harm is associated with alterations in the psychobiological stress response. Specifically, the reactivity of the autonomic nervous system (ANS) and the endocrine hypothalamic-pituitary-adrenal (HPA) axis may differ in individuals who engage in self-harm. However, evidence in this regard is inconsistent.

BACKGROUND

We conducted a preregistered random-effects meta-analysis of sympathetic ANS, parasympathetic ANS, sympathetic-parasympathetic, i.e., mixed-influence ANS, and HPA axis reactivity following laboratory stress exposure in individuals who engage in self-harm and controls. Stress exposure consisted of paradigms using either social-evaluative (e.g., TSST), emotional (e.g., negatively valenced visual stimuli), or physical (e.g., cold pressor test) challenges. A total of 29 studies (self-harm: n = 954, controls: n = 1122, 74% females) were included in the analysis.

RESULTS

Regarding ANS reactivity to stress, no differences emerged between the two groups. However, parasympathetic ANS activity was lower before stress (g = -0.30, CI -0.51 to -0.09) and after stressor cessation (g = 0.54, CI -1.07 to -0.01) in the self-harm group compared to controls. Regarding HPA axis reactivity, individuals who engage in self-harm showed significantly lower cortisol responses to stress than did controls (g = -0.26, CI -0.45 to -0.08). After stressor cessation (i.e., during stress recovery), cortisol was also lower in individuals who engage in self-harm compared to controls (g = -0.26, CI -0.43 to -0.08).

CONCLUSIONS

Lower basal parasympathetic ANS activity and flattened cortisol responses indicate dysregulation of psychobiological stress systems in individuals who engage in self-harm. A better understanding of the psychobiological underpinnings of self-harm may allow for the establishment of biomarkers of risk stratification and treatment monitoring in affected individuals.

Physiological response to pain in female adolescents with nonsuicidal self-injury as a function of severity

BACKGROUND

Preliminary evidence indicates altered hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) response to experimental pain in individuals with nonsuicidal self-injury (NSSI). This study investigated effects of NSSI severity and severity of psychopathology on the HPA axis and ANS response to pain.

METHODS

N = 164 adolescents with NSSI and n = 45 healthy controls received heat pain stimulation. Salivary cortisol, α-amylase and blood pressure were repeatedly assessed before and after painful stimulation. Heart rate (HR) and heart rate variability (HRV) were assessed continuously. NSSI severity and comorbid psychopathology were derived from diagnostic assessments. Main and interaction effects of time of measurement and NSSI severity, adjusted for severity of adverse childhood experiences, borderline personality disorder and depression, on HPA axis and ANS response to pain were examined using regression analyses.

RESULTS

Increasing NSSI severity predicted an increasing cortisol response (χ2(3) = 12.09, p = .007) to pain. After adjusting for comorbid psychopathology, greater NSSI severity predicted decreased α-amylase levels following pain (χ2(3) = 10.47, p = .015), and decreased HR (χ2(2) = 8.53, p = .014) and increased HRV(χ2(2) = 13.43, p = .001) response to pain.

LIMITATIONS

Future research should implement several NSSI severity indicators, potentially revealing complex associations with the physiological response to pain. Assessing physiological responses to pain in NSSI in a naturalistic setting presents a promising avenue for future research in NSI.

CONCLUSIONS

Findings indicate an increased pain-related HPA axis response and an ANS response characterized by reduced sympathetic and increased parasympathetic activity associated with NSSI severity. Results support claims for dimensional approaches to NSSI and its related psychopathology alongside shared, underlying neurobiological correlates.

Stress-induced alterations in resting-state functional connectivity among adolescents with non-suicidal self-injury

BACKGROUND

Non-suicidal self-injury (NSSI) is a major mental health problem among youth worldwide. Dysfunction in emotion regulation contributes to NSSI, but research on the underlying neurobiological mechanisms of NSSI is limited. Adolescents with emotion regulation difficulties are vulnerable to stress, making them susceptible to maladaptive coping mechanisms such as NSSI.

METHODS

This study examined the functional neurocircuitry relevant to emotion regulation and stress coping in individuals with NSSI compared with healthy controls. This case-control study included 34 adolescents with NSSI (15.91 years) and 28 (16.0 years) unaffected controls. Participants underwent a functional magnetic resonance imaging scan before and after completing a laboratory stress-induction paradigm (the Montreal Imaging Stress Test). The effects of stress induction were quantified by both physiological measures and self-reports.

RESULTS

Participants with NSSI showed distinctive alterations in functional resting-state following stress induction, which differentiated them from unaffected controls. Results show a reduction in functional connectivity between frontoparietal regions and the angular gyrus within the patient group compared to controls, as well as an increase in functional connectivity between visual regions, the insular cortex, the planum polare, and the central opercular cortex. After conditions of acute stress, adolescents with NSSI show changes in functional connectivity of regions associated with sensorimotor alertness, attention, and effortful emotion regulation.

LIMITATIONS

The patient group showed both NSSI and suicidal behavior, therefore results might be partly due to suicidality.

CONCLUSION

The findings emphasize the importance of targeting emotion regulation within therapeutic approaches to enhance stress coping capacity, which in turn may contribute to counteracting self-injurious behavior.

Autonomic dysregulation and self-injurious thoughts and behaviours in children and young people: A systematic review and meta-analysis

Background

Self-injurious thoughts and behaviours (SITBs) have been associated with dysfunction of the Autonomic Nervous System (ANS) in children and young people, suggesting that objective ANS measures may aid assessment of suicide risk, but a systematic synthesis of this literature is currently lacking.

Methods

Following a pre-registered protocol (PROSPERO CRD42022327605), we conducted a systematic search of PubMed, Medline, Embase, PsycINFO, and Web of Science, for empirical studies published until 10th May 2022 that compared indices of ANS functioning in individuals aged 0-25 years with versus without SITBs, or reported continuous associations between ANS measures and SITBs. Study quality was assessed with the Newcastle-Ottawa Scales. Pooled effect sizes (Hedge's g) were estimated with random-effects meta-analytic models.

Results

Twenty studies (1979 participants) were included in our systematic review, with 16 included in meta-analyses. Results suggested that SITBs were associated with altered cardiac indices of arousal (g = -0.328, p < 0.001), which was driven by lower heart rate variability in individuals with SITBs (g = -0.375, p = 0.025). Overall results for electrodermal activity were not significant (g = 0.026, p = 0.857), but subgroup analyses showed increased activity in studies of individuals who engaged specifically in non-suicidal self-harm (g = 0.249, p = 0.014) but decreased activity in the remaining studies (g = -0.567, p = 0.004).

Conclusions

Our systematic review and meta-analysis found evidence of reduced parasympathetic regulation as well as more tentative evidence of altered electrodermal activity in children and young people displaying SITBs. Future longitudinal studies should test the clinical utility of these markers for detecting and monitoring suicide risk.

Methylation of the Glucocorticoid Receptor Gene (NR3C1) in Adolescents with a History of Childhood Adversity Engaging in Non-Suicidal Self-Injury

INTRODUCTION

Non-suicidal self-injury (NSSI) is a large phenomenon among adolescents, and adverse childhood experiences (ACEs) are a major risk factor in its development. Malfunctioning of the hypothalamus-pituitary-adrenal (HPA) axis has been repeatedly reported for ACE as well as for NSSI. The glucocorticoid receptor (GR) is essential for the correct functioning of the HPA axis, thus alterations in the expression of the GR through altered methylation of the GR gene (NR3C1) (and more specifically exon 1F) might contribute to the development of NSSI in individuals with a history of ACEs, as has been reported for different other mental disorders.

METHODS

In this case-control study, we compared the methylation levels of exon 1F of the GR gene (NR3C1-1F) in adolescents with engagement in NSSI (n = 67) and a healthy control group (HC; n = 47). We preserved buccal swabs and used a mass spectrometry-based method called EpiTYPER for analyzing mean methylation of NR3C1-1F.

RESULTS

Adolescents in the NSSI group reported significantly more ACEs. The mean methylation level was about 3% in both groups with no significant group differences. Furthermore, no significant relation was found between ACE and methylation of NR3C1-1F, neither in the overall sample nor in the NSSI or HC group.

CONCLUSION

Our results are contradictory to previous research showing an increased methylation in individuals with ACE. Regarding relations between methylation of NR3C1-1F and mental disorders, previous studies reported inconsistent findings. Our study points to NSSI being either unrelated to methylation of NR3C1-1F or to yet not identified moderators on relations between methylation of NR3C1-1F and engagement in NSSI during adolescence.

[Advances in the electrophysiological research on neurocognitive function in adolescents with non-suicidal self-injury]

Non-suicidal self-injury (NSSI) is becoming increasingly common in adolescents and seriously affects their physical and mental health, and it is also a major risk factor for suicide among adolescents. NSSI has now become a public health issue of general concern; however, the identification of cognitive dysfunction in NSSI is still based on neuropsychological cognitive assessment and subjective questionnaire assessment, with a lack of objective evaluation indicators. As a method for studying the cognitive neural mechanism of NSSI, electroencephalography is a reliable tool for finding objective biomarkers of NSSI. This article reviews the recent research on electrophysiology associated with cognitive dysfunction in adolescents with NSSI.

Cybervictimization and non-suicidal self-injury among Chinese adolescents: The effect of depression and school connectedness

Cybervictimization has been shown in many studies to be a risk factor for adolescent non-suicidal self-injurious behavior (NSSI). In this study we tested the roles of depression and school connectedness in this association. The Integrative Model of NSSI, Emotion Regulation and Interpersonal Relationship Model of NSSI, and Integrative Model of Social Media and Suicide provided the conceptual framework for the study. A sample of 1106 adolescents (Mage = 13.17; SD = 0.69; 51.78% girls) completed anonymous questionnaires in their classrooms. The results of structural equation modeling showed that the positive association between cybervictimization and adolescent NSSI was mediated by depression. Moreover, this indirect link was stronger for adolescents with low vs. high school connectedness. The results have implications for intervention programs aimed at reducing NSSI among adolescents.

Do Cortisol and Dehydroepiandrosterone Influence Motivational Factors for Non-Suicidal Self-Injury in Female Adolescents?

Non-suicidal self-injury (NSSI) is a significant public health issue that particularly affects female adolescents usually emerging during puberty, with a subsequent reduction and even remission in the phenomenon later in life. The dysregulation of the hormonal stress response, particularly cortisol and dehydroepiandrosterone sulfate (DHEA-S), whose levels increase markedly during pubertal adrenarche, has been associated with the development and maintenance of a wide range of emotional disorders. Our study aims to investigate whether different cortisol-DHEA-S response patterns could be associated with the main motivational moderators to engage NSSI as well as with urgency and motivation to stop NSSI in a sample of female adolescents. We found significant correlations between stress hormones and several factors that support and sustain NSSI, specifically: cortisol levels and distressing/upsetting urge (r = 0.39 and a p = 8.94 × 10^-3) and sensation seeking (r = -0.32 and a p = 0.04), as well as cortisol/DHEA-s ratio and external emotion regulation (r = 0.40 and a p = 0.01) and desire to stop NSSI (r = 0.40 and a p = 0.01). Cortisol and DHEA-S may play a role in NSSI through the regulation of stress responses and affective states. Such results could have implications for the development of new and improved treatment and prevention plans for NSSI.

Peripheral and neural correlates of self-harm in children and adolescents: a scoping review

BACKGROUND

Self-harm in children and adolescents is difficult to treat. Peripheral and neural correlates of self-harm could lead to biomarkers to guide precision care. We therefore conducted a scoping review of research on peripheral and neural correlates of self-harm in this age group.

METHODS

PubMed and Embase databases were searched from January 1980-May 2020, seeking English language peer-reviewed studies about peripheral and neural correlates of self-harm, defined as completed suicide, suicide attempts, suicidal ideation, or non-suicidal self-injury (NSSI) in subjects, birth to 19 years of age. Studies were excluded if only investigating self-harm in persons with intellectual or developmental disability syndromes. A blinded multi-stage assessment process by pairs of co-authors selected final studies for review. Risk of bias estimates were done on final studies.

RESULTS

We screened 5537 unduplicated abstracts, leading to the identification of 79 eligible studies in 76 papers. Of these, 48 investigated peripheral correlates and 31 examined neural correlates. Suicidality was the focus in 2/3 of the studies, with NSSI and any type of self-harm (subjects recruited with suicidality, NSSI, or both) investigated in the remaining studies. All studies used observational designs (primarily case-control), most used convenience samples of adolescent patients which were predominately female and half of which were recruited based on a disorder. Over a quarter of the specific correlates were investigated with only one study. Inter-study agreement on findings from specific correlates with more than one study was often low. Estimates of Good for risk of bias were assigned to 37% of the studies and the majority were rated as Fair.

CONCLUSIONS

Research on peripheral and neural correlates of self-harm is not sufficiently mature to identify potential biomarkers. Conflicting findings were reported for many of the correlates studied. Methodological problems may have produced biased findings and results are mainly generalizable to patients and girls. We provide recommendations to improve future peripheral and neural correlate research in children and adolescents, ages 3-19 years, with self-harm.

Pituitary volume in adolescents with non-suicidal self-injury: Preliminary evidence for alterations in pituitary maturation

BACKGROUND

Non-suicidal self-injury (NSSI), typically observed in the context of various mental disorders, represents a highly prevalent and serious problem among adolescents. Based on studies linking NSSI with stress, alterations in hypothalamic-pituitary-adrenal (HPA) axis functioning have been suggested to contribute to the development and maintenance of this behavior. While research has mainly focused on cortisol - the main hormonal output of this system - to our knowledge, no study has examined pituitary gland volume (PGV) - an alternative approach of assessing HPA axis functionality that is less state-dependent - in adolescents engaging in NSSI.

METHODS

Magnetic Resonance Imaging (MRI) was performed among n = 35 adolescents (aged 12-17 years) fulfilling the diagnostic criteria for NSSI disorder according to DSM-5 and n = 31 age-matched healthy controls; PGV was obtained by manual tracing. To test for group differences - our primary aim - a hierarchical linear regression model was computed, controlling for several potential confounding variables. Since adolescence reflects a time period for significant brain development - including changes in PGV - we also tested for an age-dependent group effect. In a second step, we aimed to investigate whether differences in PGV are accounted for by the experience of childhood adversity or psychopathology. Finally, following an exploratory approach, the dimensional association between PGV and various clinical characteristics (e.g., frequency of NSSI) were explored.

RESULTS

No evidence was found for overall volumetric differences between healthy control participants and adolescents engaging in NSSI (p > 0.05) - recognizing that small effect size differences could not be detected in the present study - but group membership significantly interacted with age in predicting PGV (p = 0.02). Particularly, while PGV increased linearly with age in healthy controls (B = 61.39, SE = 14.94, p < 0.01), no corresponding association was found in NSSI patients (B = 16.83, SE = 12.20, p = 0.17). PGV was not related to adverse experiences during childhood and none of the clinical characteristics (e.g., frequency of NSSI) significantly correlated with PGV (p > 0.05).

CONCLUSION

These results provide preliminary evidence for alterations in pituitary maturation in adolescents engaging in NSSI, although replication in longitudinal studies with larger samples is warranted.

Pain and the Triple Network Model

Acute pain is a physiological response that causes an unpleasant sensory and emotional experience in the presence of actual or potential tissue injury. Anatomically and symptomatically, chronic pathological pain can be divided into three distinct but interconnected pathways, a lateral “painfulness” pathway, a medial “suffering” pathway and a descending pain inhibitory circuit. Pain (fullness) can exist without suffering and suffering can exist without pain (fullness). The triple network model is offering a generic unifying framework that may be used to understand a variety of neuropsychiatric illnesses. It claims that brain disorders are caused by aberrant interactions within and between three cardinal brain networks: the self-representational default mode network, the behavioral relevance encoding salience network and the goal oriented central executive network. A painful stimulus usually leads to a negative cognitive, emotional, and autonomic response, phenomenologically expressed as pain related suffering, processed by the medial pathway. This anatomically overlaps with the salience network, which encodes behavioral relevance of the painful stimuli and the central sympathetic control network. When pain lasts longer than the healing time and becomes chronic, the pain- associated somatosensory cortex activity may become functionally connected to the self-representational default mode network, i.e., it becomes an intrinsic part of the self-percept. This is most likely an evolutionary adaptation to save energy, by separating pain from sympathetic energy-consuming action. By interacting with the frontoparietal central executive network, this can eventually lead to functional impairment. In conclusion, the three well-known pain pathways can be combined into the triple network model explaining the whole range of pain related co-morbidities. This paves the path for the creation of new customized and personalized treatment methods.

Childhood Maltreatment, Low Serum Cortisol Levels, and Non-Suicidal Self-Injury in Young Adults With Major Depressive Disorders

BACKGROUND

Non-suicidal self-injury (NSSI) is a serious public health problem widely present among young adults and adolescents. While finding risk factors associated with NSSI among young patients with major depressive disorder (MDD) is challenging, the current study aims to measure childhood adversity and serum cortisol levels and elucidate their relationship in MDD patients with NSSI.

METHODS

In this cross-sectional study, 126 young patients with MDD (aged 16 to 35 years) were recruited. The depressive symptoms were assessed by the Beck Depression Inventory (BDI-II), and the childhood adversity was evaluated by the Chinese version of the Childhood Trauma Questionnaire (CTQ) scale. Serum cortisol levels were determined by the kits in patients.

RESULTS

Relative to MDD patients without NSSI, MDD patients with NSSI had a higher CTQ total score and its four subscores. Moreover, the cortisol levels in patients with MDD/NSSI were significantly decreased than in MDD patients without NSSI. For patients with MDD/NSSI, there is a negative association between cortisol levels and emotional neglect, but not for MDD patients without NSSI. Further regression analysis showed that low cortisol levels, BDI-II, and emotional neglect were risk factors for NSSI in young patients with MDD.

CONCLUSION

Our findings suggest that young MDD patients with NSSI experience more childhood adversity and have lower cortisol levels. Also, lower cortisol levels were associated with childhood adversity but not with depressive symptoms. Further, lower cortisol levels, depressive symptoms, and emotional neglect were risk factors for NSSI in young patients with MDD.

Advancing a temporal framework for understanding the biology of nonsuicidal self- injury: An expert review

Nonsuicidal self-injury (NSSI) is a serious clinical problem, particularly for adolescents and young adults. NSSI is a complex behavior that emerges through the intersecting effects of social, psychological, and biological mechanisms. Although the social and psychological contributions to risk for developing NSSI are relatively well understood and have guided the development of effective psychosocial treatments for self-injury, the biological mechanisms underlying NSSI have just begun to come to light. To evaluate and categorize the biological research conducted on the topic of NSSI, we propose a model that distinguishes between trait and state markers. According to this model, risk factors and mechanisms involved in NSSI can be distinguished into both trait and state factors. We review the existing evidence on distal biological traits (predictors) of NSSI, proximal biological traits (correlates) of NSSI, and biological states directly preceding or following NSSI. We conclude by providing recommendations for future research on the neurobiology of NSSI.

Borderline personality disorder

Borderline personality disorder (BPD) is a mental disorder with a high burden on patients, family members, and health-care systems. The condition was previously regarded as untreatable, but progress in understanding and management has resulted in earlier diagnosis and better treatment outcomes. A coherent syndrome of BPD typically onsets during adolescence (after age 12 years). BPD is often preceded by or co-develops with symptoms of internalising disorders (depression and anxiety), externalising disorders (conduct problems, hyperactivity, and substance use), or both. BPD is associated with various poor outcomes, including low occupational and educational attainment, lack of long-term relationships, increased partner conflict, sexual risk-taking, low levels of social support, low life satisfaction, and increased service use. Psychotherapy is the main treatment for BPD; drug treatment is only indicated for comorbid conditions that require medication, or during a crisis if psychosocial interventions are insufficient. Awareness of BPD by non-specialists, as well as specialists, is key to appropriate early intervention.

Co-ordination of brain and heart oscillations during non-rapid eye movement sleep

Oscillatory activities of the brain and heart show a strong variation across wakefulness and sleep. Separate lines of research indicate that non‐rapid eye movement (NREM) sleep is characterised by electroencephalographic slow oscillations (SO), sleep spindles, and phase–amplitude coupling of these oscillations (SO–spindle coupling), as well as an increase in high‐frequency heart rate variability (HF‐HRV), reflecting enhanced parasympathetic activity. The present study aimed to investigate further the potential coordination between brain and heart oscillations during NREM sleep. Data were derived from one sleep laboratory night with polysomnographic monitoring in 45 healthy participants (22 male, 23 female; mean age 37 years). The associations between the strength (modulation index [MI]) and phase direction of SO–spindle coupling (circular measure) and HF‐HRV during NREM sleep were investigated using linear modelling. First, a significant SO–spindle coupling (MI) was observed for all participants during NREM sleep, with spindle peaks preferentially occurring during the SO upstate (phase direction). Second, linear model analyses of NREM sleep showed a significant relationship between the MI and HF‐HRV (F = 20.1, r² = 0.30, p < 0.001) and a tentative circular‐linear correlation between phase direction and HF‐HRV (F = 3.07, r² = 0.12, p = 0.056). We demonstrated a co‐ordination between SO–spindle phase–amplitude coupling and HF‐HRV during NREM sleep, presumably related to parallel central nervous and peripheral vegetative arousal systems regulation. Further investigating the fine‐graded co‐ordination of brain and heart oscillations might improve our understanding of the links between sleep and cardiovascular health.

A Rhesus Monkey Model of Non-suicidal Self-Injury

Non-suicidal self-injury (NSSI) is a type of behavioral pathology seen not only in a variety of clinical conditions but also among non-clinical populations, particularly adolescents and young adults. With the exception of rare genetic conditions that give rise to self-harming behaviors, the etiology of NSSI and the events that trigger specific episodes of this behavior remain poorly understood. This review presents the features of an important, extensively studied animal model of NSSI, namely spontaneously occurring self-injurious behavior (SIB) in rhesus macaque monkeys. We compare and contrast rhesus monkey SIB with NSSI with respect to form, prevalence rates, environmental and biological risk factors, behavioral correlates, proposed functions, and treatment modalities. Many parallels between rhesus monkey SIB and NSSI are demonstrated, which supports the validity of this animal model across several domains. Determining the etiology of spontaneously occurring SIB in monkeys, its underlying biological mechanisms, and which pharmacological agents are most effective for treating the disorder may aid in identifying potential risk factors for the occurrence of NSSI in humans and developing medications for severe cases that are resistant to conventional psychotherapeutic approaches.

Blood pressure-related hypoalgesia: a systematic review and meta-analysis

OBJECTIVE

Spontaneous or experimentally induced high blood pressure (BP) is associated with reduced pain perception, known as BP-related hypoalgesia. Despite its clinical implications, such as the interference with early detection of myocardial infarction in 'at risk' groups, the size of the association between high BP and pain has not yet been quantified. Moreover, the distinct association between high BP and physiological or psychological components of pain has not yet been considered so far. The aim of this study was to overcome this gap by performing separate meta-analyses on nociceptive response versus quantifiable perceptual measures of pain in relation to high BP.

METHODS

PubMed and Web of Knowledge databases were searched for English language studies conducted in humans. Fifty-nine studies were eligible for the analyses. Pooled effect sizes (Hedges' g) were compared. Random effect models were used. Results show that higher BP is significantly associated with lower nociceptive response (g = 0.38; k = 6) and reduced pain perception, assessed by quantifiable measures (g = 0.48; k = 59).

RESULTS

The association between BP and pain perception, derived from highly heterogeneous studies, was characterized by significant publication bias. BP assessment, pain assessment, site of pain stimulation, percentage of female participants in the sample, and control for potential confounders were significant moderators.

CONCLUSION

Current meta-analytic results confirm the presence of BP-related hypoalgesia and point towards the need for a better understanding of its underlying mechanisms.

Longitudinal Changes After Amygdala Surgery for Intractable Aggressive Behavior: Clinical, Imaging Genetics, and Deformation-Based Morphometry Study-A Case Series

BACKGROUND

Intractable aggressive behavior (iAB) is a devastating behavioral disorder that may affect psychiatric patients. These patients have reduced quality of life, are more challenging to treat as they impose a high caregiver burden and require specialized care. Neuromodulatory interventions targeting the amygdala, a key hub in the circuitry of aggressive behavior (AB), may provide symptom alleviation.

OBJECTIVE

To Report clinical and imaging findings from a case series of iAB patients treated with bilateral amygdala ablation.

METHODS

This series included 4 cases (3 males, 19-32 years old) who underwent bilateral amygdala radiofrequency ablation for iAB hallmarked by life-threatening self-injury and social aggression. Pre- and postassessments involved full clinical, psychiatric, and neurosurgical evaluations, including scales quantifying AB, general agitation, quality of life, and magnetic resonance imaging (MRI).

RESULTS

Postsurgery assessments revealed decreased aggression and agitation and improved quality of life. AB was correlated with testosterone levels and testosterone/cortisol ratio in males. No clinically significant side effects were observed. Imaging analyses showed preoperative amygdala volumes within normal populational range and confirmed lesion locations. The reductions in aggressive symptoms were accompanied by significant postsurgical volumetric reductions in brain areas classically associated with AB and increases in regions related to somatosensation. The local volumetric reductions are found in areas that in a normal brain show high expression levels of genes related to AB (eg, aminergic transmission) using gene expression data provided by the Allen brain atlas.

CONCLUSION

These findings provide new insight into the whole brain neurocircuitry of aggression and suggest a role of altered somatosensation and possible novel neuromodulation targets.

[Pain perception and nonsuicidal self-injurious behavior]

This review focuses on studies of pain threshold and tolerance in individuals with nonsuicidal self-injurious (NSSI) behavior. The data on methods of pain sensitivity studies are presented, with issues in animal modeling of NSSI discussed separately. The results of neuroimaging studies on pain sensitivity in individuals with NSSI are described, along with contribution of genetic factors, psychological variables, and disturbances in opioid and hypothalamic-pituitary-adrenal systems. A critical methodological analysis of the studies on pain sensitivity in individuals with NSSI was performed.

Pain sensitivity and plasma beta-endorphin in adolescent non-suicidal self-injury

BACKGROUND

Beta-endorphin (BE) has been suggested to play a central role as to why people engage in NSSI. To our knowledge, no study has systematically assessed this potential relationship in adolescents with NSSI.

METHODS

94 adolescents with NSSI (according to DSM-5 criteria) and 35 healthy controls (HC) were enrolled. All participants received heat pain stimulation, with pain threshold and tolerance measured in °C. Plasma BE levels were assessed. Sociodemographic and clinical characteristics were obtained via semi-structured interviews and self-report questionnaires.

RESULTS

Adolescents with NSSI showed increased pain thresholds (t₍₁₂₇₎=2.071, p=.040), lower pain intensity (t₍₁₁₄₎==2.122, p=.036) and lower plasma BE levels (t₁₂₇==3.182, p=.002) compared to HC. Groups did not differ on pain tolerance (t₍₁₂₇₎=0.911, p=.364). Greater pain threshold correlated positively with borderline personality disorder (BPD) symptoms (r=0.182, p=.039), while pain intensity (r=-0.206, p=.033) and BE levels (r=-0.246, p=.007) correlated negatively with depression severity. No significant relationship was found between pain threshold and plasma BE (r=-0.013, p=.882).

LIMITATIONS

Future studies should implement repeated plasma BE measures to assess BE release in association with pain in NSSI. Validity of plasma BE measures compared to central measures should be considered. Assessing the association between pain sensitivity (PS) and BE in a naturalistic setting presents a promising avenue for future research in NSSI.

CONCLUSIONS

Findings support both reduced PS and basal opioid deficiency as independent biological correlates and potential risk-factors for NSSI. Further longitudinal and experimental studies are needed to investigate the role of BE levels and PS as well as their potential association.

High-frequency ecological momentary assessment of emotional and interpersonal states preceding and following self-injury in female adolescents

Non-suicidal self-injury (NSSI) is a considerable health problem among adolescents. Affect regulation by means of self-injury may promote the maintenance of NSSI. However, existing findings have limited ecological validity. The present study aimed to assess emotional and interpersonal states preceding and following incidents of NSSI in female adolescents. Adolescents with NSSI-disorder completed ecological momentary assessments of affective and interpersonal states on an hourly basis for multiple days. Multilevel mixed-effect regression analyses were conducted to assess antecedences and consequences of acts of self-injury. Data from n = 73 female adolescents covering a total of 52 acts of self-injury were available for analyses. The urge to self-injure on the between subject-level and negative affect on the within-level were best predictors of self-injury. Surprisingly, self-injury increased negative affect and decreased feelings of attachment (mother only) in the following hour. In line with findings in adults, results illustrate the important association between negative affect and self-injury in female adolescents. However, the occurrence of NSSI itself was related to concurrent increases in negative affect, and even prospectively predicted a consecutive increase in negative affect. Therefore, improvements of negative affect following (or during) self-injury, as previously reported, are at best short-lived (< 1 h).

Early life maltreatment and resting-state heart rate variability: A systematic review and meta-analysis

Recent focus on the consequences of early life adversity (ELA) in neurobiological research led to a variety of findings suggesting alterations in several physiological systems, such as the cardiovascular system. In this systematic review and meta-analysis, we focused on the relationship between early life maltreatment (ELM), one form of ELA, and resting vagal activity indexed by resting-state heart rate variability (HRV). A systematic search of the literature yielded 1'264 hits, of which 32 studies reporting data for group comparisons or correlations were included. By quantitative synthesis of existing studies using random-effect models, we found no evidence for a relationship between ELM exposure and resting vagal activity in principal. Conducting meta-regression analyses, however, we found the relationship between ELM and resting vagal activity to significantly vary as a function of both age and the presence of psychopathology. In light of the current multitude of vastly unclear pathways linking ELM to the onset of disease, we emphasize the need for further research and outline several aspects to consider in future studies.

Adolescent nonsuicidal self-injury and cortisol response to the retrieval of adversity: A sibling study

BACKGROUND

There is evidence for alterations in hypothalamus-pituitary-adrenal (HPA) axis response to the retrieval of traumatic events among individuals with Posttraumatic Stress Disorder. However, no study has so far investigated HPA response to trauma retrieval among individuals engaging in non-suicidal self-injury (NSSI). In the present study, we compared reports of childhood adversity (CA) between adolescents engaging in NSSI and their siblings and tested for differences in the cortisol response to the retrieval of CA.

METHODS

The sample consisted of 32 adolescents engaging in NSSI (M_age = 15.8 years) and their siblings (M_age = 15.6 years). Standardized interviews were used for the assessment of CA, NSSI, and axis I diagnoses. Salivary cortisol was measured before and after the trauma interview. Basal HPA axis activity was measured in hair.

RESULTS

Reports of CA were moderately interrelated between siblings. Adolescents engaging in NSSI reported more severe CA. A significant decrease of salivary cortisol during the trauma interview was found only in the NSSI group. The NSSI group had significantly higher hair cortisol levels.

CONCLUSIONS

Moderate relations in siblings' reports of CA point to non-shared experiences that may play a role in the development of NSSI. In the NSSI group, the decrease of salivary cortisol during the interview may be explained by a downregulation of the HPA axis subsequent to the retrieval of former experience of CA.

Conducting research on nonsuicidal self-injury in schools: Ethical considerations and recommendations

Research on nonsuicidal self-injury (NSSI) has grown significantly over the last 15 years, with much of this work focused on factors that initiate and maintain NSSI among school-aged youth. Although this work is important, it does raise several ethical concerns. In this article we outline key ethical issues underlying NSSI research in schools and offer recommendations for conducting ethically sound and productive research in this area. Ethical concerns addressed include: 1) recruitment of minors to research; 2) disclosure and confidentiality; 3) the risk of iatrogenic effects; 4) duty of care; 5) engaging schools in research; and 6) safety of the researchers. In each area, we offer recommendations to assist researchers, ethics committees, and schools in working together to conduct ethical NSSI research, further our understanding of NSSI, and address and respond to these behaviors in schools.

Nonsuicidal Self-Injury in Adolescents

BACKGROUND

25-35% of adolescents in random samples drawn from German schools have been found to have manifested at least one episode of nonsuicidal self-injury (NSSI). The prevalence in samples from child and adolescent psychiatric clinics is approximately 50%. NSSI can arise as a symptom in the setting of various types of mental illness.

METHODS

This review is based on a selective literature search carried out in the PubMed, PsycINFO, and Cochrane Library databases, with special consideration of regional study samples.

RESULTS

NSSI is usually resorted to as a dysfunctional coping strategy for emotional regulation. The main risk factors for NSSI include bullying, accompanying mental illnesses, and a history of abuse and neglect in childhood. Neurobiological studies have shown abnormal stress processing in persons with NSSI and an elevated pain threshold in persons with repetitive NSSI. Psychotherapeutic interventions of various kinds lessen the frequency of NSSI; to date, no particular type of psychotherapy has been found to be clearly superior to the others. Randomized controlled trials have revealed small to moderate effects from dialectic-behavioral therapy and mentalization-based therapy in adolescent patients. No psychoactive drug has yet been found to possess specific efficacy against NSSI in adolescents.

CONCLUSION

The first ever German-language clinical guidelines for the treatment of NSSI have now been issued. Psychotherapy is the treatment of first choice. More research is needed so that subgroups with different disease courses can be more clearly defined.

Longitudinal covariance of resting-state cardiac function and borderline personality disorder symptoms in adolescent non-suicidal self-injury

OBJECTIVES

Cardiac function is altered in borderline personality disorder (BPD). In adolescents with non-suicidal self-injury (NSSI) resting heart rate (HR) and vagally mediated heart rate variability (vmHRV) are associated with BPD symptoms. The study aimed to investigate longitudinal covariance of BPD symptoms and cardiac function in adolescent NSSI.

METHODS

HR and vmHRV were recorded in female adolescents with NSSI (n = 17) completing a baseline and 1-year follow-up assessment. Physiological data, structured clinical interviews and self-reports were obtained at both time points. Predictors of change in clinical outcomes and cardiac function were assessed.

RESULTS

Patients showed a reduction of NSSI (z_(34;17) = -3.79, P < 0.0001), depressive symptoms (z_(34;17) = -3.74, P < 0.0001), and increases in the level of functioning (z_(34;17) = 2.87, P = 0.004). Symptoms of BPD and frequency of BPD diagnosis did not significantly change. No significant differences on HR or vmHRV were observed. Changes in BPD symptoms were associated with changes in HR (r₍₁₇₎= 0.532, P = 0.028) and vmHRV (r₍₁₇₎ = -0.516, P = 0.033).

CONCLUSIONS

Longitudinal changes in BPD symptomatology in adolescents engaging in NSSI are associated with changes in resting cardiac function. Clinical studies are needed to investigate the utility of cardiac markers to track treatment outcome in adolescents with BPD.

Resting cardiac function in adolescent non-suicidal self-injury: The impact of borderline personality disorder symptoms and psychosocial functioning

Vagally mediated heart rate variability (vmHRV) is reduced in borderline personality disorder (BPD). Non-suicidal self-injury (NSSI) is associated with comorbid psychopathology, in particular BPD. We aimed to examine differences in cardiac function (vmHRV and heart rate [HR]) comparing adolescents (12-17 years) engaging in NSSI (n=30) and healthy controls (n=30). Further, we aimed to determine clinical concomitants of cardiac function in patients with NSSI. Analyses showed no significant group differences on cardiac function. Controlling for a host of confounding variables resting state HR and vmHRV in adolescents with NSSI were significantly correlated with BPD symptoms and the current level of functioning.