Impulsivity, aggression and brain structure in high and low lethality suicide attempters with borderline personality disorder

Childhood adversity modulates structural brain changes in borderline personality but not in major depression disorder

Adverse childhood experiences (ACEs) negatively affect the function and structure of emotion brain circuits, increasing the risk of various psychiatric disorders. It is unclear if ACEs show disorder specificity with respect to their effects on brain structure. We aimed to investigate whether the structural brain effects of ACEs differ between patients with major depression (MDD) and borderline personality disorder (BPD). These disorders share many symptoms but likely have different etiologies. To achieve our goal, we obtained structural 3T-MRI images from 20 healthy controls (HC), 19 MDD patients, and 18 BPD patients, and measured cortical thickness and subcortical gray matter volumes. We utilized the Adverse Childhood Experiences (ACE) questionnaire to quantify self-reported exposure to childhood trauma. Our findings suggest that individuals with MDD exhibit a smaller cortical thickness when compared to those with BPD. However, ACEs showed a significantly affected relationship with cortical thickness in BPD but not in MDD. ACEs were found to be associated with thinning in cortical regions involved in emotional behavior in BPD, whereas HC showed an opposite association. Our results suggest a potential mechanism of ACE effects on psychopathology involving changes in brain structure. These findings highlight the importance of early detection and intervention strategies.

Characterizing the temporal dynamics of intrinsic brain activities in depressed adolescents with prior suicide attempts

Converging evidence has revealed disturbances in the corticostriatolimic system are associated with suicidal behaviors in adults with major depressive disorder. However, the neurobiological mechanism that confers suicidal vulnerability in depressed adolescents is largely unknown. A total of 86 depressed adolescents with and without prior suicide attempts (SA) and 47 healthy controls underwent resting-state functional imaging (R-fMRI) scans. The dynamic amplitude of low-frequency fluctuations (dALFF) was measured using sliding window approach. We identified SA-related alterations in dALFF variability primarily in the left middle temporal gyrus, inferior frontal gyrus, middle frontal gyrus (MFG), superior frontal gyrus (SFG), right SFG, supplementary motor area (SMA) and insula in depressed adolescents. Notably, dALFF variability in the left MFG and SMA was higher in depressed adolescents with recurrent suicide attempts than in those with a single suicide attempt. Moreover, dALFF variability was capable of generating better diagnostic and prediction models for suicidality than static ALFF. Our findings suggest that alterations in brain dynamics in regions involved in emotional processing, decision-making and response inhibition are associated with an increased risk of suicidal behaviors in depressed adolescents. Furthermore, dALFF variability could serve as a sensitive biomarker for revealing the neurobiological mechanisms underlying suicidal vulnerability.

Neuroanatomical correlates of aggressiveness: a case-control voxel- and surface-based morphometric study

Aggression occurs across the population ranging on a symptom continuum. Most previous studies have used magnetic resonance imaging in clinical/forensic samples, which is associated with several confounding factors. The present study examined structural brain characteristics in two healthy samples differing only in their propensity for aggressive behavior. Voxel- and surface-based morphometry (SBM) analyses were performed on 29 male martial artists and 32 age-matched male controls. Martial artists had significantly increased mean gray matter volume in two frontal (left superior frontal gyrus and bilateral anterior cingulate cortex) and one parietal (bilateral posterior cingulate gyrus and precuneus) brain clusters compared to controls (whole brain: p < 0.001, cluster level: family-wise error (FWE)-corrected). SBM analyses revealed a trend for greater gyrification indices in martial artists compared to controls in the left lateral orbital frontal cortex and the left pars orbitalis (whole brain: p < 0.001, cluster level: FWE-corrected). The results indicate brain structural differences between martial artists and controls in frontal and parietal brain areas critical for emotion processing/inhibition of emotions as well as empathic processes. The present study highlights the importance of studying healthy subjects with a propensity for aggressive behavior in future structural MRI research on aggression.

Cognition in adults with borderline personality disorder

OBJECTIVE

Borderline personality disorder (BPD) is a common and disabling mental health disorder and has detrimental effects on affected individuals across multiple domains. We aimed to investigate whether individuals with BPD differ from control subjects in terms of cognitive functions, and to see if there is a relationship between cognitive functions, impulsivity, and BPD symptom severity.

METHODS

BPD individuals (n = 26; mean age = 26.7; 69.2% female) and controls (n = 58; mean age = 25.3; 51.7% female) were enrolled. Intra/Extra-Dimensional Set Shift (IED) and One Touch Stockings of Cambridge (OTS) tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to assess cognitive functions. Barratt Impulsivity Scale-version 11 (BIS-11) was administered to measure impulsivity and both the Zanarini Scale for Borderline Personality Disorder self-report and the clinician-administered versions were used to assess BPD symptom severity.

RESULTS

BPD group showed significantly impaired cognitive performance on the IED task versus controls, but there was not a significant difference in the OTS task. BPD symptom severity was positively correlated with trait (BIS-11) impulsivity and no correlation was found between BPD symptom severity and cognitive functions.

CONCLUSIONS

This study suggests people with BPD experience impaired cognitive flexibility and heightened impulsivity. Only impulsivity appeared to be directly related to symptom severity, perhaps indicating that cognitive inflexibility could be a vulnerability marker. Future research should focus on a longitudinal approach to extend clinical and theoretical knowledge in this area.

Neural correlates of aggression in personality disorders from the perspective of DSM-5 maladaptive traits: a systematic review

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published in 2013, includes an alternative model of personality disorders (AMPD) focusing on a maladaptive trait model utilized to diagnose several personality disorders. Borderline personality disorder (BPD) and antisocial personality disorder (ASPD) are two conditions categorized by AMPD that exhibit high rates of violence and aggression. Several of the traits outlined in the AMPD, including hostility, impulsivity, risk-taking, and callousness, have been previously linked to aggression in BPD and ASPD. However, to the best of our knowledge, there has never been a synthesis of neuroimaging studies that have investigated links between these traits and aggression in BPD and ASPD. To overcome this gap, we conducted a systematic review under the PRISMA framework to locate neuroimaging articles published since the release of AMPD linking trait anger/hostility, impulsivity, risk-taking, and callousness to aggression in BPD and ASPD. Key findings included the following: i) anger/hostility, associated with alterations in the interplay between prefrontal and subcortical regions (primarily the amygdala), may be a common factor explaining aggressive reactions to response to interpersonal threat or provocation; ii) alterations of fronto-temporal-limbic regions and serotonergic and endocannabinoid signaling systems may link impulsivity to aggression in BPD and ASPD; iii) weaker cortico-striatal connectivity could relate to greater risk taking and greater proclivity for violence. Insufficient evidence from neuroimaging articles was discerned to describe a relationship between callousness and aggression. Overall, results of this review reveal a relative paucity of neuroimaging studies examining AMPD traits relevant to aggression in BPD and ASPD. In addition to encouraging further investigation of neuroimaging markers of AMPD traits linked to aggression, we recommend multi-methodological designs, including the incorporation of other biomarkers, such as hormones and indices of physiological arousal, to fully expand our understanding of aggression in BPD and ASPD.

Hippocampal Dynamic Functional Connectivity, HPA Axis Activity, and Personality Trait in Bipolar Disorder with Suicidal Attempt

INTRODUCTION

Suicide in bipolar disorder (BD) is a multifaceted behavior, involving specific neuroendocrine and psychological mechanisms. According to previous studies, we hypothesized that suicidal BD patients may exhibit impaired dynamic functional connectivity (dFC) variability of hippocampal subregions and hypothalamic-pituitary-adrenal (HPA) axis activity, which may be associated with suicide-related personality traits. The objective of our study was to clarify this.

METHODS

Resting-state functional magnetic resonance imaging data were obtained from 79 patients with BD, 39 with suicidal attempt (SA), and 40 without SA, and 35 healthy controls (HCs). The activity of the HPA axis was assessed by measuring morning plasma adrenocorticotropic hormone (ACTH) and cortisol (CORT) levels. All participants underwent personality assessment using Minnesota Multiphasic Personality Inventory-2 (MMPI-2).

RESULTS

BD patients with SA exhibited increased dFC variability between the right caudal hippocampus and the left superior temporal gyrus (STG) when compared with non-SA BD patients and HCs. BD with SA also showed significantly lower ACTH levels in comparison with HCs, which was positively correlated with increased dFC variability between the right caudal hippocampus and the left STG. BD with SA had significantly higher scores of Hypochondriasis, Depression, and Schizophrenia than non-SA BD. Additionally, multivariable regression analysis revealed the interaction of ACTH × dFC variability between the right caudal hippocampus and the left STG independently predicted MMPI-2 score (depression evaluation) in suicidal BD patients.

CONCLUSION

These results suggested that suicidal BD exhibited increased dFC variability of hippocampal-temporal cortex and less HPA axis hyperactivity, which may affect their personality traits.

Aberrant connectivity in the right amygdala and right middle temporal gyrus before and after a suicide attempt: Examining markers of suicide risk

Functional neuroimaging has the potential to help identify those at risk for self-injurious thoughts and behaviors, as well as inform neurobiological mechanisms that contribute to suicide. Based on whole-brain patterns of functional connectivity, our previous work identified right amygdala and right middle temporal gyrus (MTG) connectivity patterns that differentiated Veterans with a history of a suicide attempt (SA) from a Veteran control group. In this study, we aimed to replicate and extend our previous findings by examining whether this aberrant connectivity was present prior to and after a SA. In a trauma-exposed Veteran sample (92 % male, mean age = 34), we characterized if the right amygdala and right MTG connectivity differed between a psychiatric control sample (n = 56) and an independent sample of Veterans with a history of SA (n = 17), using fMRI data before and after the SA. Right MTG and amygdala connectivity differed between Veterans with and without a history of SA (replication), while MTG connectivity also distinguished Veterans prior to engaging in a SA (extension). In a second study, neither MTG or amygdala connectivity differed between those with current suicidal ideation (n = 27) relative to matched psychiatric controls (n = 27). These results indicate a potential stable marker of suicide risk (right MTG connectivity) as well as a potential marker of acute risk of or recent SA (right amygdala connectivity) that are independent of current ideation.

Reduced suicidality after electroconvulsive therapy is linked to increased frontal brain activity in depressed patients: a resting-state fMRI study

Objective

Suicidality is commonly observed in patients with depressive episodes, and electroconvulsive therapy (ECT) has been found to be effective in treating these patients. However, the role of ECT in suicidality remains unclear. This study used resting-state functional magnetic resonance imaging (rs-fMRI) to explore the changes in brain function before and after ECT in depressed patients with suicidality.

Methods

In total, 26 depressed patients with suicidality underwent rs-fMRI at baseline and after 8-12 sessions of ECT. In addition, 32 healthy controls (HCs) matched for age, gender, and educational level underwent rs-fMRI once. The amplitude of low-frequency fluctuations (ALFF), the fractional amplitude of low-frequency fluctuations (fALFF), and regional homogeneity (ReHo) were measured to evaluate whole brain function. Differences between the groups and time points (before and after ECT) were compared. Clinical symptoms were assessed using the 17-item Hamilton Depression Scale (HAMD-17) and Beck Scale for Suicide Ideation (BSSI).

Results

At baseline, patients exhibited decreased ALFF in the right postcentral and precentral gyrus and decreased fALFF in the right supramarginal and postcentral gyrus, left superior frontal gyrus (SFG), as well as the superior and middle temporal gyrus compared to HCs. Patients also had lower ReHo in the left amygdala, anterior cingulate, and postcentral gyrus, and in the right thalamus, insula, and postcentral gyrus. They also exhibited higher ALFF in the bilateral temporal gyrus and insula as well as higher fALFF in the cerebellum. Following ECT, fALFF in the left SFG and orbital frontal cortex (OFC) significantly increased and was inversely correlated with the reduction of BSSI scores (r = -0.416, p = 0.048), whereas no correlation was found with changes in HAMD-17scores.

Conclusion

Our findings suggest that the left SFG and OFC may play a key role in the mechanism of ECT for suicidality. The decrease of fALFF in the left SFG and OFC may represent a potential mechanism through which ECT effectively treats suicidality in depressed patients.

Identifying suicide attempts, ideation, and non-ideation in major depressive disorder from structural MRI data using deep learning

The present study aims to identify suicide risks in major depressive disorders (MDD) patients from structural MRI (sMRI) data using deep learning. In this paper, we collected the sMRI data of 288 MDD patients, including 110 patients with suicide ideation (SI), 93 patients with suicide attempts (SA), and 85 patients without suicidal ideation or attempts (NS). And we developed interpretable deep neural network models to classify patients in three tasks including SA-versus-SI, SA-versus-NS, and SI-versus-NS, respectively. Furthermore, we interpreted the models by extracting the important features that contributed most to the classification, and further discussed these features or ROI/brain regions.

Aberrant dynamic functional connectivity in corticostriatal circuitry in depressed bipolar II disorder with recent suicide attempt

BACKGROUND

The underlying neurobiological mechanisms on suicidal behavior in bipolar disorder remain unclear. We aim to explore the mechanisms of suicide by detecting dynamic functional connectivity (dFC) of corticostriatal circuitry and cognition in depressed bipolar II disorder (BD II) with recent suicide attempt (SA).

METHODS

We analyzed resting-state functional magnetic resonance imaging (fMRI) data from 68 depressed patients with BD-II (30 with SA and 38 without SA) and 35 healthy controls (HCs). The whole-brain dFC variability of corticostriatal circuitry was calculated using a sliding-window analysis. Their correlations with cognitive dysfunction were further detected. Support vector machine (SVM) classification tested the potential of dFC to differentiate BD-II with SA from HCs.

RESULTS

Increased dFC variability between the right vCa and the right insula was found in SA compared to non-SA and HCs, and negatively correlated with speed of processing. Decreased dFC variability between the left dlPu and the right postcentral gyrus was found in non-SA compared to SA and HCs, and positively correlated with reasoning problem-solving. Both SA and non-SA exhibited decreased dFC variability between the right dCa and the left MTG, and between the right dlPu and the right calcarine when compared to HCs. SVM classification achieved an accuracy of 75.24 % and AUC of 0.835 to differentiate SA from non-SA, while combining the abnormal dFC features between SA and non-SA.

CONCLUSIONS

Aberrant dFC variability of corticostriatal circuitry may serve as potential neuromarker for SA in BD-II, which might help to discriminate suicidal BD-II patients from non-suicidal patients and HCs.

Changes in gray matter volume following electroconvulsive therapy in adolescent depression with suicidal ideation: A longitudinal structural magnetic resonance imaging study

Objective

We aimed to investigate changes in whole-brain gray matter volumes (GMVs) before and after electroconvulsive therapy (ECT) in adolescents with major depressive disorder (MDD) and suicidal ideation (SI).

Methods

Thirty adolescents with MDD and SI were observed, and structural magnetic resonance imaging (sMRI) was performed at baseline and after ECT for each patient. But Twenty-five healthy controls (HCs) were scanned only at baseline. The voxel-based morphometry (VBM) techniques were used to examine GMVs.

Results

Compared with HCs, MDDs at baseline showed decreased GMVs in the left middle temporal gyrus, right superior temporal gyrus, right middle temporal gyrus, left precuneus, right precuneus, and left superior frontal gyrus. After ECT, MDDs showed increased GMVs in the right superior frontal gyrus and right superior temporal gyrus. Pearson's correlation found that Beck Scale for Suicide Ideation (BSSI) scores at baseline were negatively correlated with GMVs in the left superior frontal gyrus and HAMD and BSSI scores after ECT were negatively correlated with GMVs in the right superior temporal gyrus.

Conclusion

Frontal-temporal-precuneus structure changes may be a potential cause of depressive and suicidal symptoms in adolescents. ECT may improve depressive and suicidal symptoms in adolescents by regulating brain structures to compensate original defects.

Completed Suicide by Firearm in an Individual With the Agrammatic Variant of Primary Progressive Aphasia: Case Report

The agrammatic or nonfluent variant of Primary Progressive Aphasia (nfvPPA) is a form of Frontotemporal Dementia (FTD) that is characterized by progressive language dysfunction, poor sentence construction, and low verbal fluency. Individuals with nfvPPA have intact insight into their decline, which may manifest as frustration and hopelessness, and show signs of impulsivity and disinhibition. Little is known about suicide risk in this patient population. Here we describe a case of an 84 year-old male with nfvPPA who, over the course of his care, experienced a decline in language and motoric functioning which coincided with increasing irritability and impulsivity. Despite this significant decline, he denied depressive symptoms or showed any suicidal tendencies, and he seemed to be looking forward to future events. His suicide, committed with a handgun during what appeared to be a rather innocuous trip to the garage, came as a significant shock to his spouse, family, and his clinical care team. To our knowledge, this is the first reported case of completed suicide in a patient with the nfvPPA subtype of FTD. Though this patient demonstrated demographic risk factors for suicide (advanced age, retired military veteran with easy access to firearms) there is a lack of data regarding how FTD may have contributed. Retained insight especially seems to be a risk factor for suicide across all forms of dementia. Impulsivity may be key when considering suicidality amongst FTD patients. Additionally, this case demonstrates the importance of addressing gun safety as there are few guidelines around gun ownership in this patient population.

Aggression in borderline personality disorder: A systematic review of neuroimaging studies

Aggressive behaviors are prevalent among patients with Borderline Personality Disorder (BPD). Neuroimaging studies have linked aggression in BPD patients to neurochemical, structural, functional, and metabolic alterations in various brain regions, especially in frontal-limbic areas. This systematic review summarizes current neuroimaging results on aggression among BPD patients and provides an overview of relevant brain mechanisms. A systematic search of PubMed and Web of Science databases, in addition to manual check of references, identified thirty-two eligible articles, including two magnetic resonance spectrum (MRS), thirteen structural magnetic resonance imaging (sMRI), six functional magnetic resonance imaging (fMRI), and eleven positron emission tomography (PET) studies. The reviewed studies have highlighted the abnormalities in prefrontal cortices and limbic structures including amygdala and hippocampus. Less studies have zoomed in the roles of parietal and temporal regions or taken a network perspective. Connectivity studies have shed light on the importance of the frontal-limbic interactions in regulating aggression. Conflicted findings might be attributed to disparity in controlling gender, anatomical subdivisions, and comorbidities, which shall be considered in future studies.

Brain Correlates of Suicide Attempt in 18,925 Participants Across 18 International Cohorts

BACKGROUND

Neuroimaging studies of suicidal behavior have so far been conducted in small samples, prone to biases and false-positive associations, yielding inconsistent results. The ENIGMA-MDD Working Group aims to address the issues of poor replicability and comparability by coordinating harmonized analyses across neuroimaging studies of major depressive disorder and related phenotypes, including suicidal behavior.

METHODS

Here, we pooled data from 18 international cohorts with neuroimaging and clinical measurements in 18,925 participants (12,477 healthy control subjects and 6448 people with depression, of whom 694 had attempted suicide). We compared regional cortical thickness and surface area and measures of subcortical, lateral ventricular, and intracranial volumes between suicide attempters, clinical control subjects (nonattempters with depression), and healthy control subjects.

RESULTS

We identified 25 regions of interest with statistically significant (false discovery rate < .05) differences between groups. Post hoc examinations identified neuroimaging markers associated with suicide attempt including smaller volumes of the left and right thalamus and the right pallidum and lower surface area of the left inferior parietal lobe.

CONCLUSIONS

This study addresses the lack of replicability and consistency in several previously published neuroimaging studies of suicide attempt and further demonstrates the need for well-powered samples and collaborative efforts. Our results highlight the potential involvement of the thalamus, a structure viewed historically as a passive gateway in the brain, and the pallidum, a region linked to reward response and positive affect. Future functional and connectivity studies of suicidal behaviors may focus on understanding how these regions relate to the neurobiological mechanisms of suicide attempt risk.

Functional alterations of the suicidal brain: a coordinate-based meta-analysis of functional imaging studies

Altered brain activities in suicidal subjects have been reported in a number of neuroimaging studies. However, the activity aberrances were inconsistent in previous investigations. Thus, we aimed to address activity abnormalities in suicidal individuals. Databases were searched to perform a meta-analysis of whole-brain functional MRI studies of suicidal individuals through January 14, 2020. Meta-analyses were conducted using Seed-based d Mapping software. Based on a meta-analysis of 17 studies comprising 381 suicidal individuals and 642 controls, we mainly found that increased activity in the bilateral superior temporal gyrus, left middle temporal gyrus, and bilateral middle occipital gyrus, along with decreased activity in the right putamen and left insula, were detected in suicidal individuals compared with nonsuicidal subjects. To reduce methodological heterogeneity between the included studies, subanalyses of behavioral domains were conducted, and the right superior temporal gyrus was found to increase in all subanalyses of domains. In subanalyses of suicidal attempters and ideators, suicide attempters displayed hyperactivation in the bilateral superior temporal gyrus and left middle temporal gyrus and blunted responses in the left insula relative to controls. Suicidal ideators demonstrated elevated activation in the right middle occipital gyrus and reduced activity in the right putamen relative to controls. The bilateral superior temporal gyrus was the most robust finding, replicable in all data sets in the jackknife sensitive analysis. Moreover, increased activity in the right superior temporal gyrus, left middle temporal gyrus, and right middle occipital gyrus was found to be involved with higher suicide ideation scores. This study revealed several brain regions associated with suicidality. These findings may contribute to our understanding of the pathophysiology of suicide and have important implications for suicide prevention and interventions.

Correlations of impulsivity and aggressive behaviours among adolescents in Shanghai, China using bioecological model: cross-sectional data from Global Early Adolescent Study

OBJECTIVE

To examine the correlations between impulsivity and aggressive behaviours among Chinese adolescents.

DESIGN

A school-based cross-sectional study.

SETTING

Three primary middle schools located in less developed communities of Shanghai.

PARTICIPANTS

1524 adolescents aged 11-16 years.

MEASURES

The impulsivity was measured by Barratt Impulsivity Scale, and the aggressive behaviours were determined by self-reports. Data were collected through computer-assisted self-interview using tablets. Multivariate Firth logistic regression model was conducted to examine correlations between total, attentional, motor, and non-planning impulsivity and aggressive behaviours, respectively.

RESULTS

Totally, 7.48% of participants reported aggressive behaviours toward others during the past 6 months. The proportion of aggressors among boys and girls was 10.60% and 4.18%, respectively. Results of the multivariate regression suggested the risk of aggressive behaviours was significantly increased among those with the highest tertile of total impulsivity (adjusted OR (aOR)_boys=3.14, 95% CI: 1.48 to 6.65; aOR_girls=3.74, 95% CI: 1.10 to 12.76) and motor impulsivity (aOR_boys=2.91, 95% CI: 1.46 to 5.82; aOR_girls=3.57, 95% CI: 1.25 to 10.20.), comparing with those with the lowest tertile, for boys and girls, respectively. Besides, younger age, lower social cohesion and being bullied within 6 months were associated with a higher risk of aggressive behaviours among girls. Less family caring and being bullied within 6 months were associated with the risk among boys.

CONCLUSIONS

The present study indicates a positive association between impulsivity and aggressive behaviours, with a more salient correlation between motor impulsivity subtrait and aggressive behaviour among both boys and girls. Furthermore, adolescents' aggressive behaviours were affected by multiple factors from individuals, family, peers and community. Comprehensive intervention strategies such as controlling the aggressor's impulsivity, helping them better channel their anger, creating a better family, school and neighbourhood environment, and providing support and services for victims of violence are needed.

Aggression, Impulsivity and Suicidal Behavior in Depressive Disorders: A Comparison Study between New York City (US), Madrid (Spain) and Florence (Italy)

The association of aggression and impulsivity with suicidal behavior (SB) in depression may vary across countries. This study aimed (i) to compare aggression and impulsivity levels, measured with the Brown-Goodwin Scale (BGS) and the Barratt Impulsivity Scale (BIS), respectively, between New York City (NYC) (US), Madrid (Spain) and Florence (Italy) (ANOVA); and (ii) to investigate between-site differences in the association of aggression and impulsivity with previous SB (binary logistic regression). Aggression scores were higher in NYC, followed by Florence and Madrid. Impulsivity levels were higher in Florence than in Madrid or NYC. Aggression and impulsivity scores were higher in suicide attempters than in non-attempters in NYC and in Madrid. SB was associated with aggression in NYC (OR 1.12, 95% CI 1.07–1.16; p < 0.001) and in Florence (OR 1.11, 95% CI 1.01–1.22; p = 0.032). Impulsivity was linked with SB in NYC (OR 1.01, 95% CI 1.00–1.02; p < 0.001) and in Madrid (OR 1.03, 95% CI 1.02–1.05; p < 0.001). The higher suicide rates in NYC, compared to Madrid or Florence, may be, in part, explained by these cross-cultural differences in the contribution of aggression-impulsivity to SB, which should be considered by future research on SB prevention.

Translating Interventional Neuroscience to Suicide: It's About Time

Despite significant advances in psychiatric and psychological treatment over the last 30 years, suicide deaths have increased. Unfortunately, neuroscience insights have yielded few translational interventions that specifically target suicidal thoughts and behaviors. In our view, this is attributable to two factors. The first factor is our limited integration of neurocircuitry models with contemporary suicide theory. The second challenge is inherent to the variable nature of suicide risk over time. Few interventional neuroscience studies evaluate how temporal fluctuations in risk affect treatment, despite evidence that temporality is a key component distinguishing suicide phenotypes. To wit, individual variability in risk trajectories may provide different treatment targets to engage as a patient moves between suicidal ideation and attempt. Here, we first review contemporary ideation-to-action theories of suicide from a neurobiological perspective, focusing on valence and executive function circuits and the key role of state-induced (e.g., within stressful contexts) functional modulation on longitudinal risk trajectories. We then describe neural correlates of suicide reduction following various interventions, ranging from circuit specific (i.e., transcranial magnetic stimulation) to broader pharmacological (i.e., ketamine, lithium) to psychological (i.e., brief cognitive therapy). We then introduce novel strategies for tracking risk in naturalistic settings and real time using ecological momentary interventions. We provide a critical integration of the literature focusing on the intersection between targets and temporality, and we conclude by proposing novel research designs integrating real-time and biologically based interventions to generate novel strategies for future suicide reduction research.

Multimodal Neuroimaging of Suicidal Thoughts and Behaviors in a U.S. Population-Based Sample of School-Age Children

OBJECTIVE

Suicide deaths and suicidal thoughts and behaviors are considered a public health emergency, yet their underpinnings in the brain remain elusive. The authors examined the classification accuracy of individual, environmental, and clinical characteristics, as well as multimodal brain imaging correlates, of suicidal thoughts and behaviors in a U.S. population-based sample of school-age children.

METHODS

Children ages 9-10 years (N=7,994) from a population-based sample from the Adolescent Brain Cognitive Development study were assessed for lifetime suicidal thoughts and behaviors. After quality control procedures, structural MRI (N=6,238), resting-state functional MRI (N=4,134), and task-based functional MRI (range, N=4,075-4,608) were examined. Differences with Welch's t test and equivalence tests, with observed effect sizes (Cohen's d) and their 90% confidence intervals <|0.15|, were examined. Classification accuracy was examined with area under precision-recall curves (AUPRCs).

RESULTS

Among the 7,994 unrelated children (females, N=3,757, 47.0%), those with lifetime suicidal thoughts and behaviors based on child (N=684, 8.6%), caregiver (N=654, 8.2%), and concordant (N=198, 2.5%) reports had higher levels of social adversity and psychopathology, among themselves and their caregivers, compared with never-suicidal children (N=6,854, 85.7%). Only one imaging test survived statistical correction: caregiver-reported suicidal thoughts and behaviors were associated with a thinner left bank of the superior temporal sulcus. On the basis of the prespecified bounds of |0.15|, approximately 48% of the group mean differences for child-reported suicidal thoughts and behaviors comparisons and approximately 22% for caregiver-reported suicidal thoughts and behaviors comparisons were considered equivalent. All observed effect sizes were relatively small (d≤|0.30|), and both non-imaging and imaging correlates had low classification accuracy (AUPRC ≤0.10).

CONCLUSIONS

Commonly applied neuroimaging measures did not reveal a discrete brain signature related to suicidal thoughts and behaviors in youths. Improved approaches to the neurobiology of suicide are critically needed.

Volumetric MRI Analysis of Brain Structures in Patients with History of First and Repeated Suicide Attempts: A Cross Sectional Study

Structural brain changes are found in suicide attempters and in patients with mental disorders. It remains unclear whether the suicidal behaviors are related to atrophy of brain regions and how the morphology of specific brain areas is changing with each suicide attempt. The sample consisted of 56 patients hospitalized after first suicide attempt (first SA) (n = 29), more than one suicide attempt (SA > 1) (n = 27) and 54 healthy controls (HC). Brain volume was measured using FreeSurfer 6.0 automatic segmentation technique. In comparison to HC, patients with first SA had significantly lower cortical thickness of the superior and rostral middle frontal areas, the inferior, middle and superior temporal areas of the left hemisphere and superior frontal area of the right hemisphere. In comparison to HC, patients after SA > 1 had a significantly lower cortical thickness in ten areas of frontal cortex of the left hemisphere and seven areas of the right hemisphere. The comparison of hippocampus volume showed a significantly lower mean volume of left and right parts in patients with SA > 1, but not in patients with first SA. The atrophy of frontal, temporal cortex and hippocampus parts was significantly higher in repeated suicide attempters than in patients with first suicide attempt.

Identification of suicidality in adolescent major depressive disorder patients using sMRI: A machine learning approach

BACKGROUND

Suicidal behavior is a major concern for patients who suffer from major depressive disorder (MDD), especially among adolescents and young adults. Machine learning models with the capability of suicide risk identification at an individual level could improve suicide prevention among high-risk patient population.

METHODS

A cross-sectional assessment was conducted on a sample of 66 adolescents/young adults diagnosed with MDD. The structural T1-weighted MRI scan of each subject was processed using the FreeSurfer software. The classification model was conducted using the Support Vector Machine - Recursive Feature Elimination (SVM-RFE) algorithm to distinguish suicide attempters and patients with suicidal ideation but without attempts.

RESULTS

The SVM model was able to correctly identify suicide attempters and patients with suicidal ideation but without attempts with a cross-validated prediction balanced accuracy of 78.59%, the sensitivity was 73.17% and the specificity was 84.0%. The positive predictive value of suicide attempt was 88.24%, and the negative predictive value was 65.63%. Right lateral orbitofrontal thickness, left caudal anterior cingulate thickness, left fusiform thickness, left temporal pole volume, right rostral anterior cingulate volume, left lateral orbitofrontal thickness, left posterior cingulate thickness, right pars orbitalis thickness, right posterior cingulate thickness, and left medial orbitofrontal thickness were the 10 top-ranked classifiers for suicide attempt.

CONCLUSIONS

The findings indicated that structural MRI data can be useful for the classification of suicide risk. The algorithm developed in current study may lead to identify suicide attempt risk among MDD patients.

Borderline personality disorder and prior suicide attempts define a severity gradient among hospitalized adolescent suicide attempters

BACKGROUND

Borderline personality disorder (BPD) and history of prior suicide attempt (SA) have been shown to be high predictors for subsequent suicide. However, no previous study has examined how both factors interact to modify clinical and suicide severity among adolescents.

METHODS

This study presents a comprehensive assessment of 302 adolescents (265 girls, mean age = 14.7 years) hospitalized after a SA. To test clinical interactions between BPD and history of prior SA, the sample was divided into single attempters without BPD (non-BPD-SA, N = 80), single attempters with BPD (BPD-SA, N = 127) and multiple attempters with BPD (BPD-MA, N = 95).

RESULTS

Univariate analyses revealed a severity gradient among the 3 groups with an additive effect of BPD on the clinical and suicide severity already conferred by a history of SA. This gradient encompassed categorical (anxiety and conduct disorders and non-suicidal-self-injury [NSSI]) and dimensional comorbidities (substance use and depression severity) and suicide characteristics (age at first SA). According to regression analyses, the BPD-MA group that was associated with the most severe clinical presentation also showed specific features: the first SA at a younger age and a higher prevalence of non-suicidal self-injury (NSSI) and anxiety disorders. The BPD-MA group was not associated with higher impulsivity or frequency of negative life events.

CONCLUSIONS

Based on these findings and to improve youth suicide prevention, future studies should systematically consider BPD and the efficacy of reinforcing early interventions for anxiety disorders and NSSI.

Magnetoencephalographic Correlates of Suicidal Ideation in Major Depression

BACKGROUND

Defining the neurobiological underpinnings of suicidal ideation (SI) is crucial to improving our understanding of suicide. This study used magnetoencephalographic gamma power as a surrogate marker for population-level excitation-inhibition balance to explore the underlying neurobiology of SI and depression. In addition, effects of pharmacological intervention with ketamine, which has been shown to rapidly reduce SI and depression, were assessed.

METHODS

Data were obtained from 29 drug-free patients with major depressive disorder who participated in an experiment comparing subanesthetic ketamine (0.5 mg/kg) with a placebo saline infusion. Magnetoencephalographic recordings were collected at baseline and after ketamine and placebo infusions. During scanning, patients rested with their eyes closed. SI and depression were assessed, and a linear mixed-effects model was used to identify brain regions where gamma power and both SI and depression were associated. Two regions of the salience network (anterior insula, anterior cingulate) were then probed using dynamic causal modeling to test for ketamine effects.

RESULTS

Clinically, patients showed significantly reduced SI and depression after ketamine administration. In addition, distinct regions in the anterior insula were found to be associated with SI compared with depression. In modeling of insula-anterior cingulate connectivity, ketamine lowered the membrane capacitance for superficial pyramidal cells. Finally, connectivity between the insula and anterior cingulate was associated with improvements in depression symptoms.

CONCLUSIONS

These findings suggest that the anterior insula plays a key role in SI, perhaps via its role in salience detection. In addition, transient changes in superficial pyramidal cell membrane capacitance and subsequent increases in cortical excitability might be a mechanism through which ketamine improves SI.

A systematic review of structural MRI investigations within borderline personality disorder: Identification of key psychological variables of interest going forward

Existing models of Borderline Personality Disorder (BPD) suggest that a combination of genetic vulnerability, childhood trauma, and disrupted attachment can lead to the marked emotional lability, impulsivity and interpersonal difficulties observed clinically. Brain structural differences in frontal, limbic and hippocampal regions have been reported in BPD. Less clear is how specific psychological factors relate to these structural differences, and how consistently this is found across studies. This was the focus of the present review. Eighteen studies published between 2004 and 2018 met inclusion criteria encompassing 990 participants. Study quality was assessed using the Nottingham-Ottawa Scale. We also introduce a newly devised scale to assess MRI reporting quality. The most frequently investigated psychological variable were impulsivity (9 studies), depression (8), trauma (6), aggression (6), severity of symptoms (3), global functioning, abuse and dissociation (2). Study quality varied, however, a trend was observed where newer studies were higher in reporting quality. Impulsivity demonstrated greater association with frontal structures, trauma related to the hypothalamus and limbic systems, and aggression with hippocampal and frontal structures. The present review recommends greater exploration of neurocognitive and psychosis-related features such as delusions, paranoia and voice-hearing in future studies, and to investigate cortical changes in longitudinal designs.

Imaging suicidal thoughts and behaviors: a comprehensive review of 2 decades of neuroimaging studies

Identifying brain alterations that contribute to suicidal thoughts and behaviors (STBs) are important to develop more targeted and effective strategies to prevent suicide. In the last decade, and especially in the last 5 years, there has been exponential growth in the number of neuroimaging studies reporting structural and functional brain circuitry correlates of STBs. Within this narrative review, we conducted a comprehensive review of neuroimaging studies of STBs published to date and summarize the progress achieved on elucidating neurobiological substrates of STBs, with a focus on converging findings across studies. We review neuroimaging evidence across differing mental disorders for structural, functional, and molecular alterations in association with STBs, which converges particularly in regions of brain systems that subserve emotion and impulse regulation including the ventral prefrontal cortex (VPFC) and dorsal PFC (DPFC), insula and their mesial temporal, striatal and posterior connection sites, as well as in the connections between these brain areas. The reviewed literature suggests that impairments in medial and lateral VPFC regions and their connections may be important in the excessive negative and blunted positive internal states that can stimulate suicidal ideation, and that impairments in a DPFC and inferior frontal gyrus (IFG) system may be important in suicide attempt behaviors. A combination of VPFC and DPFC system disturbances may lead to very high risk circumstances in which suicidal ideation is converted to lethal actions via decreased top-down inhibition of behavior and/or maladaptive, inflexible decision-making and planning. The dorsal anterior cingulate cortex and insula may play important roles in switching between these VPFC and DPFC systems, which may contribute to the transition from suicide thoughts to behaviors. Future neuroimaging research of larger sample sizes, including global efforts, longitudinal designs, and careful consideration of developmental stages, and sex and gender, will facilitate more effectively targeted preventions and interventions to reduce loss of life to suicide.

Efficacy of transcranial direct current stimulation in reducing impulsivity in borderline personality disorder (TIMBER): study protocol of a randomized controlled clinical trial

Background

Impulsivity is a core feature of borderline personality disorder (BPD) and is closely related to suicide risk and destructive and aggressive behaviors. Although transcranial direct current stimulation (tDCS) has shown its promising effects as an intervention to modulate impulsivity, no study has explored its potential regarding BPD.

Methods/design

This is a multicenter, crossover, double-blind study comparing active versus sham tDCS (2 mA, 30 min), applied over the dorsolateral prefrontal cortex for five consecutive days in 50 BPD patients. Participants will be assessed for impulsivity, depressive symptoms, and suicide risk. The main efficacy criteria on reduction of impulsivity will be the amplitude variation of one specific evoked potential detected by electroencephalography (EEG) during the balloon analogue risk task. Baseline measures will be compared to scores obtained immediately after sessions, then 12 and 30 days later.

Discussion

This study investigates the safety and effects of tDCS, which may have a significant impact on impulsivity in patients with BPD and may be useful to reduce risky behaviors.

Trial registration

ClinicalTrials.gov, NCT03498937. Registered on 17 April 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3427-z) contains supplementary material, which is available to authorized users.

Affective interference in borderline personality disorder: The lethality of suicidal behavior predicts functional brain profiles

BACKGROUND

Negative affective interference with executive cognition is associated with emotion dysregulation and behavioral dyscontrol in BPD, including a diathesis to suicidal and self-injurious behavior. While clinically well described, the neural basis of affective interference with central executive network function, and resulting suicidal behavior is poorly understood.

METHOD

In an fMRI study, 23 BPD suicide attempters completed an affectively modified Continuous Performance Task(X-CPT), in which targets and distractors were rendered on Negative, Positive and Neutral Ekman faces, with a Distorted image as a behavioral baseline. Responses to targets were contextualized by the affective context of the face. Lethality Rating Scale scores (LRS) were modeled as the primary regressor of interest on activation peaks, with HamD scores covaried.

RESULTS

In the Negative vs. Neutral contrast, LRS scores were inversely related to activation in the ACC, parietal precuneus, BG and OFC, with no positive relationships. Results were similar in the Negative vs Positive contrast. In the Neutral vs. Positive contrast, activations were much less extensive, with mixed positive and negative relationships. Contextualizing responses based on the effects of valence decreased participant's ability to distinguish between targets and distracters; however, no differences were observed between valence contexts. fMRI-estimated effects were not confounded by differences in behavioral sensitivity across contexts.

LIMITATIONS

In this female-only sample, possible gender differences were not addressed.

CONCLUSIONS

With negative affective interference, increased lethality of suicidal behavior in BPD predicted diminished neural activation in areas critical to executive cognitive function. Therapies diminishing affective interference may reduce risk of suicidal behavior.

Paranoia and risk of personality disorder in the general population

BACKGROUND

We hypothesized that paranoia is associated with personality disorder (PD) in the general population.

METHOD

This was a population-based cross-sectional survey carried out in Andalusia (Spain) using a representative sample of 4 507 participants. Paranoia was measured using the Green Paranoid Thought Scale, and risk of having a PD was screened using the Standardized Assessment of Personality Abbreviated Scale whilst borderline personality disorder (BPD) was measured with the CEPER-III Exploratory Interview of Personality disorder. Adjusted Pearsons' correlations between paranoia and PD or BPD were calculated.

RESULTS

Paranoia was associated with the risk of having PD and, more robustly, with BPD. Both associations held true for both personality outcomes (PD and BPD) when tested for two Green Paranoid Thought Scale paranoia subtypes (persecutory and reference) after accounting for the effects of age, sex and child abuse.

CONCLUSIONS

Paranoia seems to either augment the risk for, or be part of, PD/BPD. © 2019 John Wiley & Sons, Ltd.

Voxel-Based Morphometry Correlates of an Agitated-Aggressive Syndrome in the At-Risk Mental State for Psychosis and First Episode Psychosis

There are mixed reports on structural neuroimaging correlates of aggression in schizophrenia with weak evidence due to cohort overlaps and lack of replications. To our knowledge, no study examined volumetric neuroimaging correlates of aggression in early stages of psychosis. An agitated-aggressive syndrome is present in at-risk mental state (ARMS) and in first-episode psychosis (FEP) - it is unclear whether this syndrome is associated with structural brain abnormalities in early stages of psychosis. Using three-dimensional magnetic resonance imaging and a whole brain voxel-based morphometry approach, we examined 56 ARMS patients, 55 FEP patients and 25 healthy controls. We operationalized aggression using the Excited Component of the Brief Psychiatric Rating Scale (BPRS-EC) and dichotomized our patient group by median split into "BPRS-EC high" (n = 49) and "BPRS-EC low" groups (n = 62). The "BPRS-EC high" group had significantly smaller left lingual gyrus volume than HC. This finding was not present in the "BPRS-EC low" group. In addition, grey matter volume in the left lingual gyrus showed a negative linear correlation with BPRS-EC over all subjects (ρ = -0.318; p = 0.0001) and in the patient group (ρ = -0.202; p = 0.033). These findings provide first hints on structural brain abnormalities associated with an agitated-aggressive syndrome in ARMS and FEP patients.

Neuroimaging Studies of Suicidal Behavior and Non-suicidal Self-Injury in Psychiatric Patients: A Systematic Review

Background: With around 800,000 people taking their own lives every year, suicide is a growing health concern. Understanding the factors that underlie suicidality and identifying specific variables associated with increased risk is paramount for increasing our understanding of suicide etiology. Neuroimaging methods that enable the investigation of structural and functional brain markers in vivo are a promising tool in suicide research. Although a number of studies in clinical samples have been published to date, evidence about neuroimaging correlates for suicidality remains controversial. Objective: Patients with mental disorders have an increased risk for both suicidal behavior and non-suicidal self-injury. This manuscript aims to present an up-to-date overview of the literature on potential neuroimaging markers associated with SB and NSSI in clinical samples. We sought to identify consistently reported structural changes associated with suicidal symptoms within and across psychiatric disorders. Methods: A systematic literature search across four databases was performed to identify all English-language neuroimaging articles involving patients with at least one psychiatric diagnosis and at least one variable assessing SB or NSSI. We evaluated and screened evidence in these articles against a set of inclusion/exclusion criteria and categorized them by disease, adhering to the PRISMA guidelines. Results: Thirty-three original scientific articles investigating neuroimaging correlates of SB in psychiatric samples were found, but no single article focusing on NSSI alone. Associations between suicidality and regions in frontal and temporal cortex were reported by 15 and 9 studies across four disorders, respectively. Furthermore, differences in hippocampus were reported by four studies across three disorders. However, we found a significant lack of replicability (consistency in size and direction) of results across studies. Conclusions: Our systematic review revealed a lack of neuroimaging studies focusing on NSSI in clinical samples. We highlight several potential sources of bias in published studies, and conclude that future studies should implement more rigorous study designs to minimize bias risk. Despite several studies reporting associations between SB and anatomical differences in the frontal cortex, there was a lack of consistency across them. We conclude that better-powered samples, standardized neuroimaging and analytical protocols are needed to continue advancing knowledge in this field.

Differential relations of suicidality in depression to brain activation during emotional and executive processing

Suicidal behavior is highly prevalent in major depressive disorder (MDD), though not present in all patients. It is unclear whether the tendency for suicidal behavior is associated with a unique functional neuroanatomical signature identifiable through neuroimaging. In this study, we investigated brain activation in suicidal and non-suicidal patients with MDD during facial emotion processing and executive control. Functional magnetic resonance imaging (fMRI) data from the NESDA-fMRI study (MDD patients N = 103, healthy controls N = 26, HC) were analyzed. Patients were divided in a group of suicide attempters (N = 18, SA), suicide ideators (N = 31, SI) and a patient-control group (N = 73, PC). A gender discrimination task with emotional faces and the Tower of London executive planning task were investigated. An ANOVA was performed to compare brain activation among suicidal patients (SA + SI), PC and HC first and then among SI, SA, PC and HC. Significance was determined as meeting p < .05 family wise error (FWE) corrected at the voxel-level. We observed that SA patients showed lower activation in the bilateral fusiform gyri during emotional faces processing compared to SI, PC and HC. No group differences were found during executive planning. Results were independent of childhood emotional maltreatment, depression severity, anxiety severity, use of psychotherapy and SSRI-use. Results suggest that a propensity for suicidal behavior in MDD is associated with abnormal emotional processing but not executive functioning, represented by altered face processing compared to non-suicidal patients and controls. While in need of replication, these results indicate that altered fusiform gyrus activation during emotion processing may serve as a marker for suicidality.

Eradicating Suicide at Its Roots: Preclinical Bases and Clinical Evidence of the Efficacy of Ketamine in the Treatment of Suicidal Behaviors

Despite the continuous advancement in neurosciences as well as in the knowledge of human behaviors pathophysiology, currently suicide represents a puzzling challenge. The World Health Organization (WHO) has established that one million people die by suicide every year, with the impressive daily rate of a suicide every 40 s. The weightiest concern about suicidal behavior is how difficult it is for healthcare professionals to predict. However, recent evidence in genomic studies has pointed out the essential role that genetics could play in influencing person's suicide risk. Combining genomic and clinical risk assessment approaches, some studies have identified a number of biomarkers for suicidal ideation, which are involved in neural connectivity, neural activity, mood, as well as in immune and inflammatory response, such as the mammalian target of rapamycin (mTOR) signaling. This interesting discovery provides the neurobiological bases for the use of drugs that impact these specific signaling pathways in the treatment of suicidality, such as ketamine. Ketamine, an N-methyl-d-aspartate glutamate (NMDA) antagonist agent, has recently hit the headlines because of its rapid antidepressant and concurrent anti-suicidal action. Here we review the preclinical and clinical evidence that lay the foundations of the efficacy of ketamine in the treatment of suicidal ideation in mood disorders, thereby also approaching the essential question of the understanding of neurobiological processes of suicide and the potential therapeutics.

Structural and functional alterations of the suicidal brain: An updated review of neuroimaging studies

Brain imaging is a non-invasive and in vivo direct estimation of detailed brain structure, regional brain functioning and estimation of molecular processes in the brain. The main objective of this review was to analyze functional and structural neuroimaging studies of individuals at risk for suicide. We reviewed articles published between 2005 and 2018, indexed in PubMed and Medline, assessing structural and functional alterations of the brain of individuals at high risk for suicide and at low risk for suicide. We reviewed functional and structural neuroimaging studies which included individuals with a history of suicidal ideation or attempt in major depressive disorder (MDD), bipolar disorder (BD), psychosis, and borderline personality disorder (BPD). We selected 45 papers that focused on suicidality in MDD, 17 papers on BD, 11 papers on psychosis, and 5 papers on BPD. The suicidal brain across psychiatric diagnoses seems to heavily involve dysfunction of the fronto-temporal network, primarily involving reductions of gray and white matter volumes in the pre-frontal cortex (PFC), anterior cingulate, and superior temporal gyrus. Nonetheless, there are several ways to define suicidal behaviour and ideation. Therefore, it still remains difficult to combine the evidence from imaging studies that used different definitions of suicidality.

Correlates of Aggression in Personality Disorders: an Update

PURPOSE OF REVIEW

This review article aims at giving an update on studies investigating correlates of aggression in personality disorders during the last 5 years.

RECENT FINDINGS

Most data refer to borderline personality disorder (BPD) and antisocial personality disorder (ASPD). In BPD, emotion dysregulation, hypersensitivity to interpersonal rejection/threat, increased rumination, increased negative urgency, aggression-related knowledge structures, and invalidation were either corroborated or emerged as psychological correlates of aggression, while reduced ambiguity sensitivity, hyposensitivity to interpersonal threat, and reduced mindfulness were associated with aggression in ASPD. Neurobiologically, alterations of the monoaminooxidase-A-, the oxytocinergic-, and the prefrontal-limbic-system as well as increases of the thyroid hormone T3, γ-aminobutyric acid and several inflammatory markers were associated with increased aggression across various personality disorders. Our understanding of correlates of aggression in personality disorders has increased over the last 5 years. More efforts in improving the conceptualization of personality disorders and aggression are needed to develop innovative treatments for those affected.

Cognition As a Therapeutic Target in the Suicidal Patient Approach

The current considerations about completed suicides and suicide attempts in different cultures call the attention of professionals to this serious public health problem. Integrative approaches have shown that the confluence of multiple biological and social factors modulate various psychopathologies and dysfunctional behaviors, such as suicidal behavior. Considering the level of intermediate analysis, personality traits and cognitive functioning are also of great importance for understanding the suicide phenomenon. About cognitive factors, we can group them into cognitive schemas of reality interpretation and underlying cognitive processes. On the other hand, different types of primary cognitive alterations are related to suicidal behavior, especially those resulting from changes in frontostriatal circuits. Among such cognitive mechanisms can be highlighted the attentional bias for environmental cues related to suicide, impulsive behavior, verbal fluency deficits, non-adaptive decision-making, and reduced planning skills. Attentional bias consists in the effect of thoughts and emotions, frequently not conscious, about the perception of environmental stimuli. Suicidal ideation and hopelessness can make the patient unable to find alternative solutions to their problems other than suicide, biasing their attention to environmental cues related to such behavior. Recent research efforts are directed to assess the possible use of attention bias as a therapeutic target in patients presenting suicide behavior. The relationship between impulsivity and suicide has been largely investigated over the last decades, and there is still controversy about the theme. Although there is strong evidence linking impulsivity to suicide attempts. Effective interventions address to reduce impulsivity in clinical populations at higher risk for suicide could help in the prevention. Deficits in problem-solving ability also seem to be distorted in patients who attempt suicide. Understanding cognitive changes in patients who attempt suicide open an important perspective in the approach of patients with mental disorders. Identifying cognitive deficits in these patients, along with personality traits, depressive symptoms, and suicidal cognitive schemas may indicate to the psychiatrist the need for emergency care. Behavioral and cognitive interventions have been associated with reductions in suicide ideation, as well as suicide attempts in different populations.

Structural brain abnormalities in patients with type I bipolar disorder and suicidal behavior

Some studies have identified brain morphological changes in the frontolimbic network (FLN) in bipolar subjects who attempt suicide (SA). The present study investigated neuroanatomical abnormalities in the FLN to find a possible neural signature for suicidal behavior in patients with bipolar disorder type I (BD-I). We used voxel-based morphometry to compare euthymic patients with BD-I who had attempted suicide (n=20), who had not attempted suicide (n=19) and healthy controls (HCs) (n=20). We also assessed the highest medical lethality of their previous SA. Compared to the participants who had not attempted suicide, the patients with BD-I who had attempted suicide exhibited significantly increased gray matter volume (GMV) in the right rostral anterior cingulate cortex (ACC), which was more pronounced and extended further to the left ACC in the high-lethality subgroup (p<0.05, with family-wise error (FWE) correction for multiple comparisons using small-volume correction). GMV in the insula and orbitofrontal cortex was also related to suicide lethality (p<0.05, FWE-corrected). The current findings suggest that morphological changes in the FLN could be a signature of previous etiopathogenic processes affecting regions related to suicidality and its severity in BD-I patients.

Biomarkers of Suicide Attempt Behavior: Towards a Biological Model of Risk

PURPOSE OF REVIEW

The rising suicide rate in the USA will not be reversed without improved risk assessment and prevention practices. To date, the best method for clinicians to assess a patient's risk for suicide is screening for past suicide attempts in the patient and their family. However, neuroimaging, genomic, and biochemical studies have generated a body of findings that allow description of an initial heuristic biological model for suicidal behavior that may have predictive value.

RECENT FINDINGS

We review studies from the past 3 years examining potential biological predictors of suicide attempt behavior. We divide findings into two major categories: (1) structural and functional brain imaging findings and (2) biochemical and genomic findings encompassing several systems, including major neurotransmitters (serotonin, catecholamines, GABA, and glutamate), the hypothalamic pituitary adrenal (HPA) axis, the inflammasome, lipids, and neuroplasticity. The biomarkers that appear promising for assessing suicide risk in clinical settings include indices of serotonergic function, inflammation, neuronal plasticity, and lipids.

Hyper-modulation of brain networks by the amygdala among women with Borderline Personality Disorder: Network signatures of affective interference during cognitive processing

Emotion dysregulation is a core characteristic of patients with Borderline Personality Disorder (BPD), and is often attributed to an imbalance in fronto-limbic network function. Hyperarousal of amygdala, especially in response to negative affective stimuli, results in affective interference with cognitive processing of executive functions. Clinical consequences include the impulsive-aggression, suicidal and self-injurious behaviors which characterize BPD. Dysfunctional interactions between amygdala and its network targets have not been well characterized during cognitive task performance. Using psychophysiological interaction analysis (PPI), we mapped network profiles of amygdala interaction with key regulatory regions during a Go No-Go task, modified to use negative, positive and neutral Ekman faces as targets. Fifty-six female subjects, 31 BPD and 25 healthy controls (HC), completed the affectively valenced Go No-Go task during fMRI scanning. In the negative affective condition, the amygdala exerted greater modulation of its targets in BPD compared to HC subjects in Rt. OFC, Rt. dACC, Rt. Parietal cortex, Rt. Basal Ganglia, and Rt. dlPFC. Across the spectrum of affective contrasts, hypermodulation in BPD subjects observed the following ordering: Negative > Neutral > Positive contrast. The amygdala seed exerted modulatory effects on specific target regions important in processing response inhibition and motor impulsiveness. The vulnerability of BPD subjects to affective interference with impulse control may be due to specific network dysfunction related to amygdala hyper-arousal and its effects on prefrontal regulatory regions such as the OFC and dACC.

Impulsivity and aggression mediate regional brain responses in Borderline Personality Disorder: An fMRI study

Fronto-limbic brain networks involved in regulation of impulsivity and aggression are abnormal in Borderline Personality Disorder (BPD). However, it is unclear whether, or to what extent, these personality traits actually modulate brain responses during cognitive processing. Using fMRI, we examined the effects of trait impulsivity, aggression, and depressed mood on regional brain responses in 31 female BPD and 25 control subjects during a Go No-Go task using Ekman faces as targets. First-level contrasts modeled effects of negative emotional context. Second-level regression models used trait impulsivity, aggression and depressed mood as predictor variables of regional brain activations. In BPD, trait impulsivity was positively correlated with activation in the dorsal anterior cingulate cortex, orbital frontal cortex (OFC), basal ganglia (BG), and dorsolateral prefrontal cortex, with no areas of negative correlation. In contrast, aggression was negatively correlated with activation in OFC, hippocampus, and BG, with no areas of positive correlation. Depressed mood had a generally dampening effect on activations. Effects of trait impulsivity on healthy controls differed from effects in BPD, suggesting a disorder-specific response. Negative emotional context and trait impulsivity, but not aggression or depression, diminished task performance across both groups. Negative emotional context may interfere with cognitive functioning in BPD through interaction with the neurobiology of personality traits.

Resting-state functional MRI of abnormal baseline brain activity in young depressed patients with and without suicidal behavior

BACKGROUND

Suicide among youth is a major public health challenge, attracting increasing attention. However, the neurobiological mechanisms and the pathophysiology underlying suicidal behavior in depressed youths are still unclear. The fMRI enables a better understanding of functional changes in the brains of young suicide attempters with depressive disorder through detecting spontaneous neural activity. The purpose of this study was to identify the relationship between abnormalities involving local brain function and suicidal attempts in depressed youths using resting-state fMRI (RS-fMRI).

METHOD

Thirty-five depressed youths aged between 15 and 29 years with a history of suicidal attempts (SU group), 18 patients without suicidal attempts (NSU group) and 47 gender-, age- and education-matched healthy controls (HC) underwent psychological assessment and R-fMRI. The differences in fractional amplitude of low-frequency fluctuation (ALFF) among the three groups were compared. The clinical factors correlated with z-score ALFF in the regions displaying significant group differences were investigated. The ROC method was used to evaluate these clusters as markers to screen patients with suicidal behavior.

RESULTS

Compared with the NSU and HC groups, the SU group showed increased zALFF in the right superior temporal gyrus (r-STG), left middle temporal gyrus (L-MTG) and left middle occipital gyrus (L-MOG). Additionally, significantly decreased zALFF values in the L-SFG and L-MFG were found in the SU group compared with the NSU group, which were negatively correlated with BIS scores in the SU group. Further ROC analysis revealed that the mean zALFF values in these two regions (sensitivity=83.3% and specificity=71.4%) served as markers to differentiate the two patient subtypes.

CONCLUSION

The SU group had abnormal spontaneous neural activity during the resting state, and decreased activity in L-SFG and L-MFG was associated with increased impulsivity in SU group. Our results suggested that abnormal neural activity in these brain regions may represent a potential neurobiological diathesis or predisposition to suicidal behavior in youth depression.

Suicide attempters with Borderline Personality Disorder show differential orbitofrontal and parietal recruitment when reflecting on aversive memories

Suicidal behavior and difficulty regulating emotions are hallmarks of Borderline Personality Disorder (BPD). This study examined neural links between emotion regulation and suicide risk in BPD. 60 individuals with BPD (all female, mean age = 28.9 years), 46 of whom had attempted suicide, completed a fMRI task involving recalling aversive personal memories. Distance trials assessed the ability to regulate emotion by recalling memories from a third-person, objective viewpoint. Immerse trials assessed emotional reactivity and involved recalling memories from a first-person perspective. Behaviorally, both groups reported less negative affect on Distance as compared to Immerse trials. Neurally, two sets of findings were obtained. The first reflected differences between attempters and non-attempters. When immersing and distancing, attempters showed elevated recruitment of lateral orbitofrontal cortex, a brain region implicated in using negative cues to guide behavior. When distancing, attempters showed diminished recruitment of the precuneus, a region implicated in memory recall and perspective taking. The second set of findings related to individual differences in regulation success - the degree to which individuals used distancing to reduce negative affect. Here, we observed that attempters who successfully regulated exhibited precuneus recruitment that was more similar to non-attempters. These data provide insight into mechanisms underlying suicide attempts in BPD. Future work may examine if these findings generalize to other diagnoses and also whether prior findings in BPD differ across attempters and non-attempters.

Predictors of suicide attempts in 3.322 patients with affective disorders and schizophrenia spectrum disorders

This study explores risk factors for suicide attempts using the electronic health records of 3322 patients with either schizophrenia spectrum disorders or affective disorders who underwent a comprehensive psychiatric evaluation at the Emergency Department at the Long Island Jewish Medical Center or the Hillside Evaluation Center at The Zucker Hillside Hospital from August 3rd 2011 to July 5th 2012. Multivariate regression analyses showed, after adjusting for sex, that previous suicidal attempts and financial or relationship losses were significantly associated with a current suicidal attempt. Additionally, higher odds of having a suicidal attempt were also found in those subjects with a diagnosis of an affective disorder, compared to a schizophrenia spectrum diagnosis, and those patients in the children/adolescent group compared to those in the adult/elderly group. Our study results confirm and expand results from prior studies. Therefore, physicians should be alert for the presence of any or all of these factors upon evaluation of psychiatric patients, and if present, either psychiatric hospitalization or a close psychiatric follow up in collaboration with family and a therapist would be key in reducing the risk of potential suicidal behavior.

Affective context interferes with brain responses during cognitive processing in borderline personality disorder: fMRI evidence

Emotion dysregulation in borderline personality disorder (BPD) is associated with loss of cognitive control in the face of intense negative emotion. Negative emotional context may interfere with cognitive processing through the dysmodulation of brain regions involved in regulation of emotion, impulse control, executive function and memory. Structural and metabolic brain abnormalities have been reported in these regions in BPD. Using novel fMRI protocols, we investigated the neural basis of negative affective interference with cognitive processing targeting these regions. Attention-driven Go No-Go and X-CPT (continuous performance test) protocols, using positive, negative and neutral Ekman faces, targeted the orbital frontal cortex (OFC) and the anterior cingulate cortex (ACC), respectively. A stimulus-driven Episodic Memory task, using images from the International Affective Pictures System, targeted the hippocampus (HIP). Participants comprised 23 women with BPD, who were compared with 15 healthy controls. When Negative>Positive faces were compared in the Go No-Go task, BPD subjects had hyper-activation relative to controls in areas reflecting task-relevant processing: the superior parietal/precuneus and the basal ganglia. Decreased activation was also noted in the OFC, and increased activation in the amygdala (AMY). In the X-CPT, BPD subjects again showed hyper-activation in task-relevant areas: the superior parietal/precuneus and the ACC. In the stimulus-driven Episodic Memory task, BPD subjects had decreased activation relative to controls in the HIP, ACC, superior parietal/precuneus, and dorsal prefrontal cortex (dPFC) (for encoding), and the ACC, dPFC, and HIP for retrieval of Negative>Positive pictures, reflecting impairment of task-relevant functions. Negative affective interference with cognitive processing in BPD differs from that in healthy controls and is associated with functional abnormalities in brain networks reported to have structural or metabolic abnormalities. Task demands exert a differential effect on the cognitive response to negative emotion in BPD compared with control subjects.

Gender differences in aggression of borderline personality disorder

Aggression is a core feature of borderline personality disorder (BPD). Well-replicated results from the general population indicate that men engage in aggression more frequently than women. This article addresses the question of whether gender also influences aggression in BPD, and whether the neurobiological mechanisms underlying aggressive behavior differ between male and female BPD patients. Data show that most self-reports, interviews and behavioral tasks investigating samples of BPD patients do not find enhanced aggressiveness in male patients, suggesting that BPD attenuates rather than aggravates gender differences usually present in the general population. Neurobiological studies comparing BPD patients with gender-matched healthy controls, however, reveal a number of interesting gender differences: On the one hand, there are well-replicated findings of reduced amygdala and hippocampal gray matter volumes in female BPD patients, while these findings are not shared by male patients with BPD. On the other hand, only male BPD patients exhibit reduced gray matter volume of the anterior cingulate cortex, increased gray matter volume of the putamen, reduced striatal activity during an aggression task, and a more pronounced deficit in central serotonergic responsivity. These neurobiological findings point to a particular importance of impulsivity for the aggression of male BPD patients. Limitations include the need to control for confounding influences of comorbidities, particularly as male BPD patients have been consistently found to show higher percentages of aggression-predisposing comorbid disorders, such as antisocial personality disorder, than female BPD patients. In the future, studies which include systematic comparisons between females and males are warranted in order to disentangle gender differences in aggression of BPD patients with the aim of establishing gender-sensitive treatments where needed.