Gender differences in a fenfluramine-activated FDG PET study of borderline personality disorder

Altered cortical thickness and emotional dysregulation in adolescents with borderline personality disorder

Background: Emotional dysregulation is a core feature of borderline personality disorder (BPD). Previous studies have reported that abnormal grey matter volume is associated with the limbic-cortical circuit and default mode network (DMN) in patients with BPD. However, alterations of cortical thickness in adolescents with BPD have not been well evaluated.Objective: The aim of this study was to assess cortical thickness and its association with emotional dysregulation in adolescents with BPD.Method: This prospective study enrolled 52 adolescents with BPD and 39 age- and sex-matched healthy controls (HCs). Assessments included brain magnetic resonance imaging (MRI) acquisition with structural and resting-state functional MRI data, and clinical assessment for emotional dysregulation using the Difficulties in Emotion Regulation Scale (DERS). Cortical thickness and seed-based functional connectivity were analysed with FreeSurfer 7.2 software. Correlation analysis between cortical thickness and the scores from emotional assessment was performed with Spearman analysis.Results: Compared to HCs, there was altered cortical thickness in the DMN and limbic-cortical circuit in adolescents with BPD (Monte Carlo correction, all p < .05). These regions with altered cortical thickness were significantly associated with emotional dysregulation (all p < .05). There were also alterations of functional connectivity, i.e. with increased connectivity of the right prefrontal cortex with bilateral occipital lobes, or with the limbic system, and with decreased connectivity among the DMN regions (voxel p < .001, cluster p < .05, family-wise error corrected).Conclusions: Our results suggest that the altered cortical thickness and altered functional connectivity in the limbic-cortical circuit and DMN may be involved in emotional dysregulation in adolescents with BPD.

Effects of pharmacological treatments on neuroimaging findings in borderline personality disorder: A review of FDG-PET and fNIRS studies

BACKGROUND

Borderline personality disorder (BPD) is a serious mental condition characterized by instability in identity, interpersonal relationships, emotion regulation and impulsivity. These symptoms seem to be associated to specific brain alterations, which have been largely investigated. In particular, positron emission tomography (PET) and functional near-infrared spectroscopy (fNIRS) have demonstrated abnormalities in brain metabolism and hemodynamics in BPD, specifically in the fronto-limbic system. However, the role of medications on brain metabolism and hemodynamics in BPD is still largely unknown.

METHODS

We conducted a search on PubMed, Scopus and Web of Science of PET and fNIRS studies exploring the effect of medications on brain metabolism and hemodynamics in BPD. A total of 10 studies met the inclusion criteria.

RESULTS

Overall, PET studies showed an effect of psychotropic agents on brain metabolism, especially in frontal and temporal areas. Also, higher metabolic rates in frontal areas were found to correlate with clinical improvements. In contrast, fNIRS investigations reported an inconclusive or absent effects on brain hemodynamics in BPD patients.

LIMITATIONS

The small sample size, the elevated percentage of women, the heterogeneity in pharmacological agents and the presence of comorbidities limit the conclusions of the present review.

CONCLUSIONS

Serotoninergic agents and second-generation antipsychotics produce changes in frontal and temporal metabolism in BPD, which appear to correlate with clinical improvements. Differently, brain hemodynamics do not seem to be significantly affected by the most commonly prescribed drugs in BPD, suggesting that the therapeutic actions of medications are not mediated by changes in neural hemodynamics.

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.

Borderline personality disorder and its symptom clusters: A review of positron emission tomography and single photon emission computed tomography studies

Positron emission tomography (PET) and single photon emission computed tomography (SPECT) are two neuroimaging techniques that have led to important insights into the pathophysiology of borderline personality disorder (BPD) and its symptom clusters. This paper provides the most up-to-date review of PET and SPECT studies targeting BPD. A systematic search of PET and SPECT studies using the databases PsycINFO, PubMed, and Embase was implemented, which yielded 30 articles in the end. Earlier PET studies largely reported decreased glucose metabolism in prefrontal brain regions. More recent PET research has pointed to alterations in monoaminergic systems, greater activation of the opioid system during sadness induction, as well as abnormalities of the brain endocannabinoid system in BPD. SPECT studies of BPD mainly identified changes in regional cerebral blood flow and alterations of the serotonergic system. Such PET and SPECT study abnormalities have been suggested to relate to the symptomatology of BPD, including impulsivity, aggression, and mood changes. The implications of these neuroimaging studies in terms of shedding new light on the pathophysiology of BPD and providing new avenues for drug development are discussed.

Meta-Analysis of white matter diffusion tensor imaging alterations in borderline personality disorder

Borderline personality disorder (BorPD) is characterized by instability and mood dysregulation, unstable relationships and distorted self-image. Identification of underlying anatomical and physiological changes is crucial to refine current treatments and develop new ones. In this perspective, previous magnetic resonance imaging studies have highlighted alterations associated with BorPD phenotype. In particular, diffusion-weighted imaging/Diffusion tensor imaging (DWI/DTI) has identified many white matter structural alterations in individuals with this diagnosis. Although in its infancy, limiting this line of investigation is a lack of direction at the field level. Hence, the present paper aims to conduct a meta-analysis of DWI/DTI findings in individuals with a diagnosis of BorPD, testing the hypothesis that there are specific white matter alterations associated with BorPD. To this end, we performed a meta-analysis of the existing literature of DWI/DTI in BorPD representing a total of 123 individuals with BorPD and 117 Controls. Our results indicated that individuals with BorPD show regions of reduced fractional anisotropy in the corpus callosum and fornix. These results survived all jack-knife reshuffles and showed no publication bias. This suggests that alterations in these structures may contribute to psychopathology. Further, the present results lend support to extant psychological and biological models of BorPD.

Serotonin 5-HT1A Receptor Biased Agonists Induce Different Cerebral Metabolic Responses: A [18F]-Fluorodesoxyglucose Positron Emission Tomography Study in Conscious and Anesthetized Rats

Serotonin 5-HT_1A receptors constitute an attractive therapeutic target for various psychiatric or neurodegenerative disorders. These receptors are expressed in multiple brain regions on different neuronal populations and can be coupled with distinct G-protein subtypes; such functional diversity complicates the use of 5-HT_1A ligands in several pathologies where it would be desirable to stimulate the receptors in a precise region. Therefore, using "biased agonists" able to target specifically certain subpopulations of 5-HT_1A receptors would enable achievement of better therapeutic benefit. Several 5-HT_1A receptor biased agonists are currently in development, including NLX-101 (aka F15599) and NLX-112 (aka F13640, befiradol), with preclinical data suggesting that they preferentially target different populations of 5-HT_1A receptors. However, most previous studies used invasive and regionally limited approaches. In this context, [¹⁸F]-fluorodesoxyglucose (FDG)-positron emission tomography (PET) imaging constitutes an interesting technique as it enables noninvasive mapping of the regional brain activity changes following a pharmacological challenge in conscious animals. We report here the evaluation of cerebral glucose metabolism following intraperitoneal injection of different doses of NLX-112 or NLX-101 in conscious or isoflurane-anesthetized rats. The biased agonists produced different metabolic "fingerprints" with distinct regional preferences, consistent with previous studies. At equal doses, the effect of NLX-101 was less marked than NLX-112 in the piriform cortex, in the striatum (in terms of inhibition), and in the pontine nuclei and the cerebellum (in terms of activation); furthermore, only NLX-112 increased the glucose metabolism in the parietal cortex, whereas only NLX-101 induced a clear activation in the colliculi and the frontal cortex, which may be related to its distinctive procognitive profile. Both agonist effects were almost completely unapparent in anesthetized animals, underlining the importance of studying serotonergic neurotransmission in the conscious state. In this regard, [¹⁸F]FDG-PET imaging seems very complementary with other functional imaging techniques such as pharmacological MRI.

Single-Photon Emission Computed Tomography and Positron Emission Tomography Studies of Antisocial Personality Disorder and Aggression: a Targeted Review

PURPOSE OF REVIEW

This paper aims to provide a comprehensive discussion of single-photon emission computed tomography (SPECT) and positron emission tomography (PET) studies of antisocial personality disorder (ASPD) and aggression.

RECENT FINDINGS

Among ASPD males with high impulsivity, the density of brainstem serotonin (5-HT) transporters shows a relationship with impulsivity, aggression, and ratings of childhood trauma. 5-HT_1B receptor (R) binding in the striatum, anterior cingulate cortex, and orbitofrontal cortex (OFC) correlated with anger, aggression, and psychopathic traits in another study of violent offenders, most of whom were diagnosed with ASPD. Finally, the density of monoamine oxidase-A (MAO-A), a mitochondrial enzyme that degrades 5-HT, norepinephrine, and dopamine (DA), was reported as lower in the OFC and ventral striatum of ASPD. Among non-clinical populations, 5-HT₄R binding, as an index of low cerebral 5-HT levels, has been associated with high trait aggression, but only in males. Furthermore, evidence suggests that individuals with high-activity MAO-A genetic variants compared with low-activity MAO-A allelic variants release more DA in the ventral caudate and putamen when exposed to violent imagery. There are very few PET or SPECT studies that exclusively sample individuals with ASPD. However, among ASPD samples, there is evidence of regional serotonergic abnormalities in the brain and alteration of neural MAO-A levels. Future studies should consider employing additional molecular probes that could target alternative neurotransmitter systems to investigate ASPD. Furthermore, examining different typologies of aggression in clinical and non-clinical populations using SPECT/PET is another important area to pursue and could shed light on the neurochemical origins of these traits in ASPD.

Reduced white matter integrity in borderline personality disorder: A diffusion tensor imaging study

BACKGROUND

Borderline personality disorder (BPD) has a pervasive pattern of instability in interpersonal relationships, self-image, and emotions. BPD may be linked to an abnormal brain anatomy, but little is known about possible impairments of the white matter microstructure in BPD or their relationship with impulsivity or risky behaviors. The aims of the present study were to explore the relationship between BPD and diffusion tensor imaging (DTI) parameters and psychological tests.

METHODS

We evaluated 35 un-medicated BPD patients in a medication-free state and 50 healthy controls (HCs). We performed DTI tractography in BPD patients and HCs. The Childhood Trauma Questionnaire (CTQ), Profile of Mood State (POMS), State-Trait Anxiety Inventory (STAI), Beck Depression Inventory (BDI), Social Adaptation Self-Evaluation Scale (SASS), and Depression and Anxiety Cognition Scale (DACS) were administered to BPD patients and HCs.

RESULTS

A tract-based spatial statistics (TBSS) revealed that the BPD group had three clusters with a significantly lower axial diffusivity (AD) than the HC group: one located mainly in the cingulum and the other mainly in the inferior front-occipital fasciculus and inferior longitudinal fasciculus. Regarding the AD values, one cluster correlated negatively and significantly with POMS (Depression) and it was located in the cingulum, while another cluster correlated positively and significantly with DACS (Future Denial) and it was located in the inferior front-occipital fasciculus (IFOF).

LIMITATIONS

The small sample size of this study prevents us from forming any definitive conclusions, meaning that more studies are needed to confirm our findings. We are unable to generalize our findings to include other ethnic groups.

CONCLUSIONS

Our results suggested that hypo-metabolism in a front-limbic network dysfunction is characterized by the cingulum and a front-occipital network dysfunction characterized by the occipital lobe, while an occipital-temporal network dysfunction characterized by the inferior longitudinal fasciculus.

Borderline personality disorder in men: A literature review and illustrative case vignettes

The aim is to review the salient literature on borderline personality disorder (BPD) in men and link those findings with case vignettes. We provide a literature review and then report case examples of those who met DSM and clinical BPD criteria, and consider the extent to which the small male sub-set corresponded developmentally and phenomenologically with prototypic BPD in women. The review considered phenomenological, epidemiological, biological and developmental BPD factors, finding BPD men evidence elevated substance abuse, and 'externalising' patterns of behavior, antisocial personality traits, violent self-harm and interpersonal aggression, whereas women display more 'internalising' strategies. The five male vignettes enriched the literature review providing support for gender differences reported in our review. The literature and case vignette findings should assist clinicians in recognising that BPD in men may not be as rare as generally viewed, and which may reflect BPD being commonly viewed as weighted to women and being misdiagnosed as an antisocial personality disorder (ASPD) in men.

Mapping the brain correlates of borderline personality disorder: A functional neuroimaging meta-analysis of resting state studies

BACKGROUND

Altered intrinsic function of the brain has been implicated in Borderline Personality Disorder (BPD). Nonetheless, imaging studies have yielded inconsistent alterations of brain function. To investigate the neural activity at rest in BPD, we conducted a set of meta-analyses of brain imaging studies performed at rest.

METHODS

A total of seven functional imaging studies (152 patients with BPD and 147 control subjects) were combined using whole-brain Signed Differential Mapping meta-analyses. Furthermore, two conjunction meta-analyses of neural activity at rest were also performed: with neural activity changes during emotional processing, and with structural differences, respectively.

RESULTS

We found altered neural activity in the regions of the default mode network (DMN) in BPD. Within the regions of the midline core DMN, patients with BPD showed greater activity in the anterior as well as in the posterior midline hubs relative to controls. Conversely, in the regions of the dorsal DMN they showed reduced activity compared to controls in the right lateral temporal complex and bilaterally in the orbitofrontal cortex. Increased activity in the precuneus was observed both at rest and during emotional processing. Reduced neural activity at rest in lateral temporal complex was associated with smaller volume of this area.

LIMITATIONS

Heterogeneity across imaging studies.

CONCLUSIONS

Altered activity in the regions of the midline core as well as of the dorsal subsystem of the DMN may reflect difficulties with interpersonal and affective regulation in BPD. These findings suggest that changes in spontaneous neural activity could underlie core symptoms in BPD.

A Neurobiological Model of Borderline Personality Disorder: Systematic and Integrative Review

Borderline personality disorder (BPD) is a severe mental disorder with a multifactorial etiology. The development and maintenance of BPD is sustained by diverse neurobiological factors that contribute to the disorder's complex clinical phenotype. These factors may be identified using a range of techniques to probe alterations in brain systems that underlie BPD. We systematically searched the scientific literature for empirical studies on the neurobiology of BPD, identifying 146 articles in three broad research areas: neuroendocrinology and biological specimens; structural neuroimaging; and functional neuroimaging. We consolidate the results of these studies and provide an integrative model that attempts to incorporate the heterogeneous findings. The model specifies interactions among endogenous stress hormones, neurometabolism, and brain structures and circuits involved in emotion and cognition. The role of the amygdala in BPD is expanded to consider its functions in coordinating the brain's dynamic evaluation of the relevance of emotional stimuli in the context of an individual's goals and motivations. Future directions for neurobiological research on BPD are discussed, including implications for the Research Domain Criteria framework, accelerating genetics research by incorporating endophenotypes and gene × environment interactions, and exploring novel applications of neuroscience findings to treatment research.

Gender determines cortisol and alpha-amylase responses to acute physical and psychosocial stress in patients with borderline personality disorder

Borderline personality disorder (BPD) is characterized by affective instability, unstable relationships, and identity disturbance. We measured salivary alpha-amylase (sAA) and salivary cortisol levels in all participants during exposure to the Trier Social Stress Test (TSST) and an electric stimulation stress. Seventy-two BPD patients were compared with 377 age- and gender- matched controls. The State and Trait versions of the Spielberger Anxiety Inventory test (STAI-S and STAI-T, respectively), the Profile of Mood State (POMS) tests, and the Beck Depression Inventory (BDI), the Depression and Anxiety Cognition Scale (DACS) were administered to participants before electrical stimulation. Following TSST exposure, salivary cortisol levels significantly decreased in female patients and significantly increased in male patients compared with controls. POMS tension-anxiety, depression-dejection, anger-hostility, fatigue, and confusion scores were significantly increased in BPD patients compared with controls. In contrast, vigor scores were significantly decreased in BPD patients relative to controls. Furthermore, STAI-T and STAI-S anxiety scores and BDI scores were significantly increased in BPD patient compared with controls. DACS scores were significantly increased in BPD patient compared with controls. Different stressors (e.g., psychological or physical) induced different responses in the HPA and SAM systems in female or male BPD patients.

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.

Morphometric hemispheric asymmetry of orbitofrontal cortex in women with borderline personality disorder: a multi-parameter approach

Functional imaging studies have implicated the orbitofrontal cortex (OFC) in the pathophysiology of borderline personality disorder (BPD). To date, however, volume-based magnetic resonance imaging (MRI) studies have yielded mixed results. We used a surface-based processing approach that allowed us to measure five morphometric cortical features of the OFC, including volumetric (cortical thickness and surface area) and geometric (mean curvature, depth of sulcus, and metric distortion - three indicators of cortical folding) parameters. Participants comprised 25 female BPD patients with no other current psychiatric comorbidity and 25 age- and gender-matched healthy controls who received structural MRI scans. Images were processed using the Freesurfer package. All BPD patients had a history of comorbid psychiatric disorder(s) and were currently on medications. Compared with controls, the BPD group showed reduced cortical thickness, surface area, mean curvature, depth of sulcus, and metric distortion in the right medial OFC. In the left medial OFC, the BPD group had reduced cortical thickness and mean curvature, but increased metric distortion. This study confirmed the utility of surface-based analysis in the study of BPD cortical structures. In addition, we observed extensive structural abnormalities in the medial OFC of female subjects with BPD, findings that were most pronounced in the right OFC, with preliminary data suggesting hemispheric asymmetry.

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

Impulsivity and aggressiveness are trait dispositions associated with the vulnerability to suicidal behavior across diagnoses. They are associated with structural and functional abnormalities in brain networks involved in regulation of mood, impulse and behavior. They are also core characteristics of borderline personality disorder (BPD), a disorder defined, in part, by recurrent suicidal behavior. We assessed the relationships between personality traits, brain structure and lethality of suicide attempts in 51 BPD attempters using multiple regression analyses on structural MRI data. BPD was diagnosed by the Diagnostic Interview for Borderline Patients-revised, impulsivity by the Barratt Impulsiveness Scale (BIS), aggression by the Brown-Goodwin Lifetime History of Aggression (LHA), and high lethality by a score of 4 or more on the Lethality Rating Scale (LRS). Sixteen High Lethality attempters were compared to 35 Low Lethality attempters, with no significant differences noted in gender, co-morbidity, childhood abuse, BIS or LHA scores. Degree of medical lethality (LRS) was negatively related to gray matter volumes across multiple fronto-temporal-limbic regions. Effects of impulsivity and aggression on gray matter volumes discriminated High from Low Lethality attempters and differed markedly within lethality groups. Lethality of suicide attempts in BPD may be related to the mediation of these personality traits by specific neural networks.

Microstructural white matter damage at orbitofrontal areas in borderline personality disorder

OBJECTIVES

Prefrontal cortex plays a major role in the modulation of behaviors and emotions through regulation of both information processing and impulse control. Low prefrontal function in borderline personality disorder (BPD) has been consistently reported by a number of studies using neuropsychological assessments and functional neuroimaging techniques. To further explore this findings, this study aimed to investigate microstructural damage of prefrontal white matter tracts in subjects with BPD by using the novel, voxel-based approach, tract-based spatial statistics (TBSS).

METHODS

A Diffusion Tensor Image (DTI) study was performed in 28 patients with DSM-IV BPD (13 males and 15 females) and in 26 healthy control subjects. Voxel wise analysis was performed using TBSS (diffusion toolbox of FSL - functional MRI Software Library) to localize regions of white matter showing significant changes of fractional anisotropy (FA).

RESULTS

TBSS analysis revealed a statistically significant decrease of FA in the genu and rostral areas of the corpus callosum (p<0.005), as well as in left and right prefrontal white matter fasciculi (p<0.002) in BPD participants compared with controls. White matter abnormalities were not correlated with age, neurological symptoms or comorbid ADHD.

CONCLUSIONS

Despite the reduced sample size, the results are in line with previous findings on reduced orbitofrontal functions in BPD with prominent affective-depressive feature and suggest that emotional and behavioral symptoms of BPD patients might be associated to damage at the connectivity tracts in these brain areas.

Striatal activity in borderline personality disorder with comorbid intermittent explosive disorder: sex differences

Borderline Personality Disorder (BPD) is associated with behavioral and emotional dysregulation, particularly in social contexts; however, the underlying pathophysiology at the level of brain function is not well understood. Previous studies found abnormalities in frontal cortical and limbic areas suggestive of poor frontal regulation of downstream brain regions. However, the striatum, which is closely connected with the medial frontal cortices and plays an important role in motivated behaviors and processing of rewarding stimuli, has been understudied in BPD. Here we hypothesized that, in addition to frontal dysfunction, BPD patients may show abnormal striatal function. In this study, 38 BPD patients with intermittent explosive disorder (BPD-IED) and 36 healthy controls (HC) participated in the Point Subtraction Aggression Paradigm (PSAP), a computer game played with a fictitious other player. (18)Fluoro-deoxyglucose positron emission tomography (FDG-PET) measured relative glucose metabolism (rGMR) within caudate and putamen in response to aggression-provoking and non-provoking versions of the PSAP. Male BPD-IED patients had significantly lower striatal rGMR than all other groups during both conditions, although male and female BPD-IED patients did not differ in clinical or behavioral measures. These sex differences suggest differential involvement of frontal-striatal circuits in BPD-IED, and are discussed in relation to striatal involvement in affective learning and social decision-making.

Structural brain abnormalities and suicidal behavior in borderline personality disorder

BACKGROUND

Structural brain abnormalities have been demonstrated in subjects with BPD in prefrontal and fronto-limbic regions involved in the regulation of emotion and impulsive behavior, executive cognitive function and episodic memory. Impairment in these cognitive functions is associated with increased vulnerability to suicidal behavior. We compared BPD suicide attempters and non-attempters, high and low lethality attempters to healthy controls to identify neural circuits associated with suicidal behavior in BPD.

METHODS

Structural MRI scans were obtained on 68 BPD subjects (16 male, 52 female), defined by IPDE and DIB/R criteria, and 52 healthy controls (HC: 28 male, 24 female). Groups were compared by diagnosis, attempt status, and attempt lethality. ROIs were defined for areas reported to have structural or metabolic abnormalities in BPD, and included: mid-inf. orbitofrontal cortex, mid-sup temporal cortex, anterior cingulate, insula, hippocampus, amygdala, fusiform, lingual and parahippocampal gyri. Data were analyzed using optimized voxel-based morphometry implemented with DARTEL in SPM5, co-varied for age and gender, corrected for cluster extent (p < .001).

RESULTS

Compared to HC, BPD attempters had significantly diminished gray matter concentrations in 8 of 9 ROIs, non-attempters in 5 of 9 ROIs. Within the BPD sample, attempters had diminished gray matter in Lt. insula compared to non-attempters. High lethality attempters had significant decreases in Rt. mid-sup. temporal gyrus, Rt. mid-inf. orbitofrontal gyrus, Rt. insular cortex, Lt. fusiform gyrus, Lt. lingual gyrus and Rt. parahippocampal gyrus compared to low lethality attempters.

CONCLUSIONS

Specific structural abnormalities discriminate BPD attempters from non-attempters and high from low lethality attempters.

Fronto-limbic dysfunction in borderline personality disorder: a 18F-FDG positron emission tomography study

INTRODUCTION

Several functional neuroimaging studies have demonstrated abnormalities in fronto-limbic pathways when comparing borderline personality disorder (BPD) patients with controls. The present study aimed to evaluate regional cerebral metabolism in euthymic BPD patients with similar measured impulsivity levels by means of 18F-FDG PET during resting state and to compare them against a control group.

METHODS

The present study evaluates regional cerebral metabolism in 8 euthymic BPD patients with 18F-FDG PET during resting state as compared to 8 controls with similar socio-geographic characteristics.

RESULTS

BPD patients presented a marked hypo-metabolism in frontal lobe and showed hyper-metabolism in motor cortex (paracentral lobules and post-central cortex), medial and anterior cingulus, occipital lobe, temporal pole, left superior parietal gyrus and right superior frontal gyrus. No significant differences appeared in basal ganglia or thalamus.

CONCLUSIONS

Results reveal a dysfunction in patients' frontolimbic network during rest and provide further evidence for the importance of these regions in relation to BPD symptomatology.

Gender, personality, and serotonin-2A receptor binding in healthy subjects

The vulnerability to mood disorders, impulsive-aggression, eating disorders, and suicidal behavior varies greatly with gender, and may reflect gender differences in central serotonergic function. We investigated the relationships of gender, mood, impulsivity, aggression and temperament to 5HT(2A) receptor binding in 21 healthy subjects using [18F]altanserin and PET neuroimaging. Binding potentials in pre-defined regions-of-interest (ROI) were calculated using the Logan graphical method, corrected for partial volume effects, and compared by gender with age co-varied. SPM analysis was used for voxel level comparisons. Altanserin binding (BP(P)) was greater in male than female subjects in the following nine ROIs: hippocampus (HIP) and Lt. HIP, lateral orbital frontal cortex (LOF) and Lt. LOF, left medial frontal cortex (Lt. MFC), left medial temporal cortex (Lt. MTC), left occipital cortex (Lt. OCC), thalamus (THL) and Lt. THL. Differences in Lt. HIP and Lt. MTL remained significant after Bonferroni correction. Gender differences were noted in the co-variation of psychological traits with BP(P) values in specific ROIs. Among males alone, aggression was negatively correlated with BP(P) values in Lt. LOF and Lt. MFC, and Suspiciousness positively correlated in LOF, Lt. LOF and Lt. MFC. Among female subjects alone, Negativism was positively correlated with BP(P) values in HIP, and Verbal Hostility in Lt. HIP. Altanserin binding in Lt. MTC was positively correlated with Persistence, with no significant gender effect. Gender differences in 5HT(2A) receptor function in specific ROIs may mediate expression of psychological characteristics such as aggression, suspiciousness and negativism. Future studies of 5HT(2A) receptor function and its relationship to behavior should control for gender.

Borderline personality disorder: hypothalamus pituitary adrenal axis and findings from neuroimaging studies

Borderline personality disorder (BPD) is a complex and serious mental disorder that is commonly seen psychiatric practice. Although stress, especially early life stress, seems to be associated with the development of the disorder, there has been far less research on the function of the hypothalamic-pituitary-adrenal (HPA) axis in BPD, compared to other psychiatric disorders, such as major depressive disorder and post-traumatic stress disorder. Stress has been suggested to exert damaging effects on the brain, particularly the hippocampus; therefore, neuroimaging studies yield important insight into the neurobiology of BPD. This article reviews research on the HPA axis and neuroimaging studies in BPD and aims to integrate these findings.

Neural correlates of the use of psychological distancing to regulate responses to negative social cues: a study of patients with borderline personality disorder

BACKGROUND

Emotional instability is a defining feature of borderline personality disorder (BPD); yet, little is understood about its underlying neural correlates. One possible contributing factor to emotional instability is a failure to adequately employ adaptive cognitive regulatory strategies such as psychological distancing.

METHODS

To determine whether there are differences in neural dynamics underlying this control strategy between BPD patients and healthy control (HC) subjects, blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging signals were acquired as 18 BPD and 16 HC subjects distanced from or simply looked at pictures depicting social interactions. Contrasts in signal between distance and look conditions were compared between groups.

RESULTS

Borderline personality disorder patients showed a different pattern of activation compared with HC subjects when looking at negative versus neutral pictures. When distancing versus looking at negative pictures, both groups showed decreased negative affect ratings and increased activation of the dorsolateral prefrontal cortex, areas near/along the intraparietal sulcus (IPS), ventrolateral prefrontal cortex, and posterior cingulate/precuneus regions. However, the BPD group showed less BOLD signal change in dorsal anterior cingulate cortex and IPS, less deactivation in the amygdala, and greater activation in the superior temporal sulcus and superior frontal gyrus.

CONCLUSIONS

Borderline personality disorder and HC subjects display different neural dynamics while passively viewing social emotional stimuli. In addition, BPD patients do not engage the cognitive control regions to the extent that HCs do when employing a distancing strategy to regulate emotional reactions, which may be a factor contributing to the affective instability of BPD.

Anterior cingulate volume in adolescents with first-presentation borderline personality disorder

Reports of volumetric abnormalities in the anterior cingulate cortex (ACC) in adults with established borderline personality disorder (BPD) are inconsistent, and it is not known whether such abnormalities are present early in the disorder. We aimed to investigate ACC volume in a first-presentation teenage BPD sample with minimal exposure to treatment. Fifteen female BPD patients and 15 healthy female control participants underwent magnetic resonance imaging (MRI) scanning. ACC volumes were estimated using a reliable method that accounts for inter-individual variation in sulcal morphology, and measurements were compared between the two groups. Analysis of variance revealed a decrease in volume of the left ACC in BPD patients compared with control participants. This volumetric change was correlated with parasuicidal behavior and impulsivity. A measure of ACC volume asymmetry was also correlated with fear of abandonment symptoms. Our results suggest that ACC volumetric abnormalities early in the course of BPD might be related to clinical correlates of the disorder. Longitudinal studies are needed to examine the nature of this abnormality over the course of the disorder.

Structural brain abnormalities in borderline personality disorder: a voxel-based morphometry study

Imaging studies using region-of-interest morphometry and positron emission tomography have contributed to our understanding of structural and functional abnormalities in borderline personality disorder (BPD); however, both methods have practical limitations to their usefulness for exploratory studies of brain-behavior relationships. We used voxel-based morphometry (VBM) in 34 subjects with BPD and 30 healthy control (HC) subjects to study effects of diagnosis, gender, childhood sexual abuse, depressed mood, impulsivity and aggression on group differences. VBM is a computer-based method for whole brain analysis that combines the advantages of a functional study with a structural method. The BPD subjects, diagnosed with the Diagnostic Interview for Borderline Patients and the International Personality Disorders Examination, were compared with 30 HC subjects, with age and gender covaried. Analyses were repeated separately by gender and, in women, by histories of childhood sexual abuse. Depressed mood, impulsivity, and aggression were covaried in separate analyses. Compared with HC, BPD subjects had significant bilateral reductions in gray matter concentrations in ventral cingulate gyrus and several regions of the medial temporal lobe, including the hippocampus, amygdala, parahippocampal gyrus, and uncus. BPD women (and abused BPD women), but not BPD men, had significant reductions in medial temporal lobe, including the amygdala. BPD men, but not BPD women, showed diminished gray matter concentrations in the anterior cingulate gyrus compared with findings in HC subjects. Covarying for depressed mood rendered group differences non-significant in the ventral cingulate but had little effect on differences in medial temporal cortex. Covarying for aggression (LHA) had relatively little effect on group differences, while covarying for impulsivity, as determined by the Barratt Impulsiveness Scale, rendered all previously noted voxel-level group differences non-significant. Diminished gray matter in the prefrontal cortex and the medial temporal cortex may mediate the dysregulation of impulse and affect in BPD. Group differences varied greatly by gender, levels of depression, and impulsivity. VBM is an efficient method for exploratory study of brain-behavior relationships.

Changes in glucose metabolism due to aging and gender-related differences in the healthy human brain

Using [(18)F]fluoro-deoxy-glucose-PET, we studied relative metabolic changes due to age- and gender-related differences in the brain of 126 healthy subjects from their twenties to seventies. We used a data-extraction technique, the three-dimensional stereotactic surface projections (3D-SSP) method, to measure metabolic changes with fewer effects of regional anatomic variances. Simple regression analysis revealed significant age-related increases in relative metabolic values in the parahippocampal and amygdala regions in both sexes in their twenties to forties, and significant age-related decreases in both sexes in their fifties to seventies. Relative values in the frontal lobe showed significant age-related decreases in both sexes in their twenties to forties, but these effects were not seen in subjects in their fifties to seventies. Significant gender differences in correlation coefficients of relative values with age were shown in the parahippocampal, primary sensorimotor, temporal, thalamus and vermis regions in subjects in their 20s to 40s, but disappeared in subjects in their twenties to forties, but were not apparent in subjects in their fifties to seventies except in the vermis. Males in their twenties to sixties and females in their fifties showed significant laterality in relative values in the temporal lobes. Our study demonstrated age- and gender-related differences in glucose metabolism in healthy subjects.

Recent advances in the biological study of personality disorders

While it is premature to provide a simple model for the vulnerability to the development of either borderline (BPD) or schizotypal (SPD) personality disorder, it is clear that these heritable disorders lend themselves to fruitful neurobiological exploration. The most promising findings in BPD suggest that a diminished top-down control of affective responses, which is likely to relate to deceased responsiveness of specific midline regions of prefrontal cortex, may underlie the affective hyperresponsiveness in this disorder. In addition, genetic and neuroendocrine and molecular neuroimaging findings point to a role for serotonin in this affective disinhibition. Clearly SPD falls within the schizophrenia spectrum, but precisely the nature of what predicts full-blown schizophrenia as opposed to the milder symptoms of SPD is not yet clear.

Escalated aggressive behavior: Dopamine, serotonin and GABA

The ethical dilemma in aggression research is how to reconcile two divergent objectives, namely to avoid harm and injury as much as possible and, at the same time, how to study behavioral phenomena that validly represent the essence of the neurobiology of aggression. Clinical and preclinical aggression research focuses on different types of aggression. Preclinical studies are usually stimulated by an ethological approach and focus on the phylogeny, ontogeny, survival value and neural mechanisms of ritualized displays and signals. On the other hand, clinical studies focus on violent individuals and pathologically excessive forms of aggressive behavior. This review emphasizes research on escalated forms of aggression in animals and humans and their pharmacotherapy. The current experimental models to generate escalated levels of aggressive behavior in laboratory rely on social instigation, frustrative non-reward and alcohol drinking. These types of aggression are modulated by canonical neurotransmitters like dopamine, serotonin (5-HT) and GABA. It continues to be a main goal of much neurobiological research to find potential targets of pharmacological agents that interact with dopaminergic, GABAergic and serotonergic systems and have high efficacy and selectivity to reduce excessive levels of aggressive and violent behaviors without side-effects. While the mesocorticolimbic dopamine system is implicated in the initiation, execution, termination and consequences of aggressive behavior, drugs with a high affinity for dopamine D2 receptors lack specificity for reducing aggressive behavior. Current investigations point to 5-HT(1B) receptor subtypes as particularly relevant. First, they are differentially expressed in aggression-prone individuals relative to those who are not excessively aggressive. Second, these and also other 5-HT receptor subtypes emerge to be significant targets for anti-aggressive interventions. Positive modulators of GABA(A) receptors with specific subunit configuration may be relevant for heightening aggression, and these sites may be targets for intervention. A prerequisite for rational pharmacotherapies will be adequate characterization of serotonergic and GABAergic receptor regulation in individuals exhibiting escalated aggression.