Genetics of impulsive behaviour

Exploring Neuregulin3: From physiology to pathology, a novel target for rational drug design

Neuregulin 3 (NRG3) is an epidermal growth factor related protein that binds to and stimulates the Erb-B2 receptor tyrosine kinase 4 (ErbB4). NRG3 is a multifunctional protein with fifteen alternative splicing isoforms categorized into four classes. Numerous physiological processes, such as the formation of cortical plate, cortical patterning, synaptic development, neuronal proliferation, regulation of neurotransmission, control of impulsive behavior, mammary gland morphogenesis, spermatogonial proliferation and cardiac homeostasis are influenced by NRG3. Besides its physiological roles, NRG3 also modulates anxiogenic phenotypes. It is a susceptibility gene for schizophrenia, autism spectrum disorder and Hirschsprung's Disease. Furthermore, anxiety during nicotine withdrawal is dependent on NRG3-ErbB4 signaling. Research on a range of solid carcinomas, such as brain tumors, ovarian cancer, gastrointestinal cancer and breast cancer, has demonstrated NRG3 gene as a therapeutic target. NRG3 also has potential involvement in epilepsy, angular limb malformation in Rambouillet rams, amyotrophic lateral sclerosis and polythelia. Nevertheless, little is known about the molecular characteristics, activities specific to isoforms, and molecular mechanisms of NRG3. Examining its potential involvement in a range of physiological processes and pathological states is a unique area that needs in-depth study and may offer new mechanistic insights and comprehension of these elements. Thus, the purpose of this review is to shed light on the utility of NRG3 as a potential target in various health and disease conditions.

The impact of methylphenidate on choice impulsivity is inversely associated with corpus callosum fiber integrity across sexes

BACKGROUND

Choice impulsivity represents preference towards smaller immediate rewards over larger delayed rewards. Extensive literature demonstrates that choice impulsivity can be manipulated using dopaminergic agonists such as methylphenidate (MPH), and that females exhibit elevated choice impulsivity compared to males. Sex differences are also frequently reported with respect to brain white matter (WM) fiber integrity. It has yet to be determined whether sex differences also exist in the impact of MPH on choice impulsivity, and whether these putative differences are accounted for by the integrity of differential WM fibers.

METHODS

Forty-eight healthy young adults completed the delay discounting (DD) task twice during MRI-DTI scans after receiving either MPH or placebo in a double-blind, placebo-controlled, within-subject design. WM fiber integrity was assessed using automated fiber quantification (AFQ) and tract-based spatial statistics (TBSS).

RESULTS

Compared to placebo, MPH yielded significantly reduced choice impulsivity in males but not in females. DTI data revealed reduced integrity in multiple WM fibers in females compared to males. Interestingly, the impact of MPH on choice impulsivity was negatively associated with fiber integrity in the forceps major of the corpus callosum for males only and positively associated with fiber integrity in the forceps minor of the corpus callosum for females only.

CONCLUSIONS

Taken together, results uncover sex-specific effects of MPH on choice impulsivity, accounted for by inverse associations between choice impulsivity under MPH and the structural integrity of distinct segments of the corpus callosum. These findings highlight the need to consider sex differences in the neurobiological mechanisms of impulsivity.

Faecal microbiota composition and impulsivity in a cohort of older adults with metabolic syndrome

Impulsivity is an important determinant of human behaviour, affecting self-control, reasonable thinking and food choices. Recent evidence suggests a role for gut microbiota in human behaviour, but the relationship between gut microbiota and impulsive behaviours remains largely unexplored. To address this knowledge gap, the present study aims to explore the associations between faecal microbiota composition with trait and behavioural impulsivity, in a subcohort of the PREDIMED-Plus trial, including older adults presenting overweight/obesity. Fecal samples (n = 231) were profiled for their microbiota composition using 16 S rRNA amplicon sequencing and impulsivity was determined through four different assessments. Adherence to different dietary patterns was estimated through questionnaires. Beta diversity analyses showed a significant association with the Conner's Performance Test (CPT) in multivariate-adjusted models, and, in total, 13 bacterial genera associated with CPT. Erysipelotrichaceae UCG 003 showed the highest association with CPT and known butyrate producers such as Butyricicoccus spp., Roseburia spp., and Eubacterium hallii were among the identified bacteria. The bacteria Lachnospiraceae UCG 001, Anaerostipes and Blautia were associated with CPT and also the adherence to healthy and unhealthy plant-based diets. In addition, functional analysis showed a significant negative association between the CPT and the glucuronate and galacturonate metabolic pathways. From the other impulsivity assessments, two more associations were identified, for the genus Phascolarctobacterium with the Stroop test, and the genus Lachnospiraceae GAG 54 with the positive urgency subscore of UPPS-P Impulsive Behaviour Scale. Overall, our findings suggest potential links between the faecal microbiota composition and function with behavioural impulsive inattention as determined by the CPT.

Gut Microbiome in Impulsively Violent Female Convicts

INTRODUCTION

Impulsivity and aggression are often interlinked behavioral traits that have major implications for our society. Therefore, the study of this phenomenon and derivative interventions that could lead to better control of impulsive aggression are of interest.

METHODS

We analyzed the composition and diversity of the gut bacterial microbiome of 33 impulsively violent female convicts with dissocial personality disorder and 20 non-impulsive age-matched women. Further, levels of assorted neurotransmitters and short-chain fatty acids (SCFAs) were analyzed in serum and stool samples. We also assessed all participants using a battery of psychological questionnaires and tested possible correlations between the collected clinical data and the composition and diversity of their microbiomes and metabolites.

RESULTS

We identified four bacterial amplicon sequencing variants that were differentially abundant in non-impulsive versus impulsive women - the genera Bacteroides, Barnesiella, and the order Rhodospirillales were more abundant in impulsive women. In contrast, the genus Catenisphaera was more abundant in non-impulsive women. Fecal tryptophan levels were significantly higher in impulsive women. Association analysis revealed a strong positive intercorrelation between most fecal SCFAs in the entire dataset.

CONCLUSIONS

Our study demonstrated possible associations between gut microbiomes and their metabolites and impulsive behavior in a unique cohort of prisoners convicted of violent assaults and a matched group of non-impulsive women from the same prison. Genus Bacteroides, which was differentially abundant in the two groups, encoded enzymes that affect serotonin pathways and could contribute to this maladaptive behavior. Similarly, increased fecal tryptophan levels in impulsive individuals could affect neuronal circuits in the brain.

INTRODUCTION

Impulsivity and aggression are often interlinked behavioral traits that have major implications for our society. Therefore, the study of this phenomenon and derivative interventions that could lead to better control of impulsive aggression are of interest.

METHODS

We analyzed the composition and diversity of the gut bacterial microbiome of 33 impulsively violent female convicts with dissocial personality disorder and 20 non-impulsive age-matched women. Further, levels of assorted neurotransmitters and short-chain fatty acids (SCFAs) were analyzed in serum and stool samples. We also assessed all participants using a battery of psychological questionnaires and tested possible correlations between the collected clinical data and the composition and diversity of their microbiomes and metabolites.

RESULTS

We identified four bacterial amplicon sequencing variants that were differentially abundant in non-impulsive versus impulsive women - the genera Bacteroides, Barnesiella, and the order Rhodospirillales were more abundant in impulsive women. In contrast, the genus Catenisphaera was more abundant in non-impulsive women. Fecal tryptophan levels were significantly higher in impulsive women. Association analysis revealed a strong positive intercorrelation between most fecal SCFAs in the entire dataset.

CONCLUSIONS

Our study demonstrated possible associations between gut microbiomes and their metabolites and impulsive behavior in a unique cohort of prisoners convicted of violent assaults and a matched group of non-impulsive women from the same prison. Genus Bacteroides, which was differentially abundant in the two groups, encoded enzymes that affect serotonin pathways and could contribute to this maladaptive behavior. Similarly, increased fecal tryptophan levels in impulsive individuals could affect neuronal circuits in the brain.

Neural indices of heritable impulsivity: Impact of the COMT Val158Met polymorphism on frontal beta power during early motor preparation

Studies of COMT Val158Met suggest that the neural circuitry subserving inhibitory control may be modulated by this functional polymorphism altering cortical dopamine availability, thus giving rise to heritable differences in behaviors. Using an anatomically-constrained magnetoencephalography method and stratifying the sample by COMT genotype, from a larger sample of 153 subjects, we examined the spatial and temporal dynamics of beta oscillations during motor execution and inhibition in 21 healthy Met158/Met158 (high dopamine) or 21 Val158/Val158 (low dopamine) genotype individuals during a Go/NoGo paradigm. While task performance was unaffected, Met158 homozygotes demonstrated an overall increase in beta power across regions essential for inhibitory control during early motor preparation (∼100 ms latency), suggestive of a global motor "pause" on behavior. This increase was especially evident on Go trials with slow response speed and was absent during inhibition failures. Such a pause could underlie the tendency of Met158 allele carriers to be more cautious and inhibited. In contrast, Val158 homozygotes exhibited a beta drop during early motor preparation, indicative of high response readiness. This decrease was associated with measures of behavioral disinhibition and consistent with greater extraversion and impulsivity observed in Val homozygotes. These results provide mechanistic insight into genetically-determined interindividual differences of inhibitory control with higher cortical dopamine associated with momentary response hesitation, and lower dopamine leading to motor impulsivity.

ADHD Patients with Suicidal Behaviour: Risk Factors, Comorbidities, and Clinical Profile: A Naturalistic Exploratory Study

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder that disrupts brain functioning and is characterized by hyperactivity, impulsivity, and inattention. With varying presentations and complex etiological factors contributing to the development of ADHD, along with its persistence into adulthood, ADHD must be studied. Researchers have taken an interest in the relationship between ADHD and suicide, which is a serious public health concern with increasing prevalence rates in the Americas. The current literature reveals conflicting views on the importance of psychiatric comorbidities in the development of suicidal behaviours in ADHD patients. Therefore, this study aimed to determine whether there were significant differences between adult ADHD patients with suicide risk and adult ADHD patients without suicide risk. This study was a naturalistic retrospective chart review pilot study that used a sample of adults with a confirmed diagnosis of ADHD from January 2023 to August 2023. Using convenience sampling and sets of inclusion and exclusion criteria, patient data were sequentially collected from Med Access electronic medical records. The control and experimental groups each consisted of 50 patients (100) ranging from 19 to 58 years old. Our quantitative data were analyzed using non-parametric statistical tests, including the Chi-Square test and the Mann-Whitney U test. The results showed significant associations between ADHD patients with suicide risk and (1) borderline personality disorder; (2) binge eating disorder; (3) seven specific psychosocial risk factors; and (4) a higher number of antidepressant medication trials. No significant associations were found with other psychiatric disorders; however, there are important sex differences in terms of the risk factors. Our pilot study reveals several significant differences between adult ADHD patients with suicide risk and those without suicide risk. However, given our limited sample size and limitations, we hope our study encourages larger-scale studies to further investigate this relationship to improve its generalizability.

The effects of BDNF rs6265 and FGF21 rs11665896 polymorphisms on alcohol use disorder-related impulsivity in Han Chinese adults

INTRODUCTION

Patients with alcohol use disorder (AUD) often experience repeated withdrawal. Impulsivity is the most relevant factor influencing successful withdrawal. Brain-derived neurotrophic factor (BNDF) and fibroblast growth factor 21 (FGF21) are associated with impulsivity. Previous studies on the differential effects of BDNF or FGF21 on impulsivity have focused on single-gene effects and have inconsistent results. We aim to investigate the effects of BDNF rs6265 and FGF21 rs11665896, individually and together, on impulsivity during alcohol withdrawal in patients with AUD.

METHODS

We recruited 482 adult Han Chinese males with AUD and assessed their impulsivity using the Barratt Impulsivity Scale. Genomic DNA was extracted and genotyped from peripheral blood samples. Statistical analysis was conducted on the data.

RESULTS

The T-test and 2 × 2 analysis of variance were used to investigate the effects of the genes on impulsivity. There was a significant BDNF × FGF21 interaction on no-planning impulsiveness (F = 9.15, p = 0.003, η2p = 0.03). Simple main effects analyses and planned comparisons showed that BDNF rs6265 A allele × FGF21 rs11665896 T allele was associated with higher no-planning impulsiveness. Finally, hierarchical regression analyses revealed that only the interaction of BDNF and FGF21 accounted for a significant portion of the variance in no-planning impulsiveness.

CONCLUSION AND SIGNIFICANCE

The combination of BDNF rs6265 A allele and FGF21 rs11665896 T allele may increase impulsivity and discourage alcohol withdrawal. Our study provides a possible genetic explanation for the effects of associated impulsivity in patients with AUD from the perspective of gene-gene interactions.

Aggressiveness in Italian Children with ADHD: MAOA Gene Polymorphism Involvement

ADHD is a neurodevelopmental disorder that children and adults can develop. A complex interplay of genetic and environmental factors may underlie interindividual variability in ADHD and potentially related aggressive behavior. Using high-resolution molecular biology techniques, we investigated the impact of some MAOA and SLC6A4 variations on ADHD and aggressive behavior in a group of 80 Italian children with ADHD and in 80 healthy controls. We found that homozygous genotypes of MAOA rs6323 and rs1137070 were associated with an increased risk of ADHD (p = 0.02 and p = 0.03, respectively), whereas the heterozygous genotypes (GT of rs6323 and CT of rs1137030) (p = 0.0002 and p = 0.0006) were strongly linked to a lower risk of developing this disorder. In patients with aggressive behavior, we highlighted only a weak negative association of both MAOA polymorphisms (heterozygous genotypes) with aggressiveness, suggesting that these genotypes may be protective towards specific changes in behavior (p = 0.05). Interestingly, an increase in the GG genotype of rs6323 (p = 0.01) and a decrease in GT genotype (p = 0.0005) was also found in patients without aggressive behavior compared to controls. Regarding 5HTT gene genotyping, no allele and genotype differences have been detected among patients and controls. Our work shows that defining a genetic profile of ADHD may help in the early detection of patients who are more vulnerable to ADHD and/or antisocial and aggressive behavior and to design precision-targeted therapies.

Genetics of gambling disorder and related phenotypes: The potential uses of polygenic and multifactorial risk models to enable early detection and improve clinical outcomes

Gambling Disorder (GD) is an impactful behavioural addiction for which there appear to be underpinning genetic contributors. Twin studies show significant GD heritability results and intergenerational transmission show high rates of transmission. Recent developments in polygenic and multifactorial risk prediction modelling provide promising opportunities to enable early identification and intervention for at risk individuals. People with GD often have significant delays in diagnosis and subsequent help-seeking that can compromise their recovery. In this paper we advocate for more research into the utility of polygenic and multifactorial risk modelling in GD research and treatment programs and rigorous evaluation of its costs and benefits.

A network analysis of early trauma and impulsive behavior in individuals with alcohol, cocaine, and polysubstance use disorder

OBJECTIVE

This study investigated the relationship between impulsivity and early trauma through a network analysis in individuals diagnosed with different substance use disorders.

METHODS

In a cross-sectional design, the sample included 556 men with substance use disorders (195 with alcohol use, 157 with cocaine/crack use, and 214 with polysubstance use). Early trauma and impulsive behavior were assessed using the Childhood Trauma Questionnaire and the Barratt Impulsiveness Scale, respectively. The connection between trauma and impulsivity was assessed using network analysis through a fused graphical lasso algorithm.

RESULTS

No connection was observed between impulsivity and trauma networks in individuals with alcohol use disorder. In those with cocaine use disorder, networks were linked through the motor domain and sexual abuse nodes. Inverse connections were observed between the emotional neglect node and perseverance, but not the non-planning node. In polysubstance use, the connection between impulsivity and trauma networks was weak, with the cognitive complexity node connecting to the trauma network through physical abuse. There connections were inversely proportional between the motor domain and emotional neglect nodes, as well as between cognitive instability and physical neglect.

CONCLUSION

Our results suggest that the relationship between the type of early (childhood) trauma and the expression of impulsivity could lead to different substance use profiles.

Criminal convictions in males and females diagnosed with attention deficit hyperactivity disorder: A Swedish national registry study

Background

Individuals with Attention-Deficit/Hyperactivity Disorder (ADHD) face an elevated risk of criminal convictions compared to those without ADHD. However, understanding this link involves considering sex differences, coexisting psychiatric conditions, and unmeasured familial factors. This study aimed to explore the connection between ADHD and criminal convictions (both violent and non-violent) in males and females, while also assessing the impact of comorbid psychiatric disorders and familial factors.

Methods

Using Swedish national registers, we identified individuals born between 1986 and 1997 (635,391 males and 600,548 females). ADHD was defined through clinical diagnosis and prescribed medications, while criminal convictions were determined based on Swedish lower court records. Unmeasured familial factors were accounted for using a sibling design approach.

Results

Findings revealed that individuals with ADHD had a notably higher absolute and relative risk of both violent and non-violent criminal convictions compared to those without ADHD. While criminal convictions were more frequent among males with ADHD, females with ADHD exhibited higher relative risks (HR violent 10.50, non-violent 4.04) than their male counterparts (HR violent 6.03, non-violent 3.57). Additionally, lower socioeconomic status (SES) in individuals with ADHD was associated with increased relative risks for criminal convictions compared to individuals with ADHD who had higher SES. Adjusting for childhood and internalizing psychiatric disorders partially attenuated these associations, while substance use disorders (SUD) substantially attenuated them. SUD also contributed to an elevated absolute risk of criminal convictions in both male and female individuals with ADHD. Accounting for unmeasured shared familial factors slightly reduced the estimates, but the association between ADHD and criminal convictions persisted.

Conclusion

In conclusion, ADHD remains a potent independent risk factor for criminal convictions, with varying effects based on gender. This underscores the importance of tailored crime prevention strategies and early interventions for individuals with ADHD, especially when comorbid SUD is present.

Changes in co-use of alcohol and cannabis among Nordic adolescents in the 21st century: Results from the European School Survey Project on Alcohol and Other Drugs study

INTRODUCTION

In the 21st century, there has been a decline in alcohol use among adolescents in most Nordic countries, while trends of cannabis use have diverged. We explore how alcohol and cannabis use, respectively, and co-use of the two substances, have changed among Nordic adolescents. Three hypotheses are used to frame the study: (i) cannabis use has substituted alcohol use; (ii) there has been a parallel decline in both substances; and/or (iii) there has been a 'hardening' of users, implying that alcohol users increasingly use cannabis.

METHODS

Data from the European School Survey Project on Alcohol and Other Drugs, conducted among 15- to 16-year-olds in Denmark, Finland, Iceland, Norway and Sweden (N = 74,700, 49% boys), were used to explore trends of past-year alcohol and cannabis use in the period 2003-2019.

RESULTS

The proportion of adolescents reporting alcohol use decreased significantly in all Nordic countries except Denmark. The proportion of those using cannabis only was low (0.0%-0.7%) and stable in all countries. The total number of substance use occasions declined among all adolescents in all countries but Denmark. Among alcohol users, cannabis use became increasingly prevalent in all countries but Denmark.

DISCUSSION AND CONCLUSIONS

We found no support for the 'parallel decline hypothesis' in alcohol and cannabis use among Nordic adolescents. Partially in line with the 'substitution hypothesis', cannabis use accounted for an increasing proportion of all substance use occasions. Our results suggests that the co-use of alcohol and cannabis has become more common, thus also providing support to the 'hardening' hypothesis.

The cognitive adaptability and resiliency employment screener (CARES): tool development and testing

Introduction

To decrease psychological risk for content moderators, the study initiated the first steps of developing a robust employment screening tool, namely, the Cognitive Adaptability and Resiliency Employment Screener.

Method

The study consisted of three phases with 4,839 total participants.

Results

In Phase 1, a set of 76 items were developed and tested via exploratory factor analysis, yielding three factors (i.e., Psychological Perseverance & Agility, Rumination & Emotional Lingering, and Expressiveness & Sociability) and also reducing the scale to 68 items. In Phase 2 through confirmatory factor analysis, the three-factor structure showed good fit (CFI = 0.92, RMSEA = 0.05) and demonstrated sufficient overall reliability. In Phase 3, the convergent validity and divergent validity of the tool were established relative to constructs such as resilience, cognitive control and flexibility, emotion regulation, and optimism.

Discussion

Altogether, the findings revealed that the scale demonstrated good psychometric properties that, pending future studies, may serve as a promising employment screener for content moderators.

Flexible coding schemes in dorsomedial prefrontal cortex underlie decision-making during delay discounting

Determining how an agent decides between a small, immediate versus a larger, delayed reward has provided insight into the psychological and neural basis of decision-making. The tendency to excessively discount the value of delayed rewards is thought to reflect deficits in brain regions critical for impulse control such as the prefrontal cortex (PFC). This study tested the hypothesis that dorsomedial PFC (dmPFC) is critically involved in flexibly managing neural representations of strategies that limit impulsive choices. Optogenetic silencing of neurons in the rat dmPFC increased impulsive choices at an 8 sec, but not 4 sec, delay. Neural recordings from dmPFC ensembles revealed that, at the 8-sec delay, the encoding landscape transitions to reflect a deliberative-like process rather than the schema-like processes observed at the 4-sec delay. These findings show that changes in the encoding landscape reflect changes in task demands and that dmPFC is uniquely involved in decisions requiring deliberation.

The effect of microbiome composition on impulsive and violent behavior: A systematic review

The impact of the microbiome on brain function and behavior has recently become an important research topic. We searched for a link between the gut microbiome and impulsive and violent behavior. We focused on critical factors influencing the microbiome establishment that may affect human health later in life, i.e., delivery mode, early-life feeding, and early antibiotic exposure. We searched PubMed, Web of Science, and the Cochrane Library. We included original human studies examining adults and children with impulsive and/or violent behavior that assessed the gut microbiota composition of participants, delivery mode, infant feeding mode, or early antibiotic exposure. Bibliographic searches yielded 429 articles, and 21 met the eligibility criteria. Two studies reported data on patients with schizophrenia with violent behavior, while 19 studies reported data on patients with attention-deficit hyperactivity disorder (ADHD). The results showed several bacterial taxa associated with ADHD symptomatology and with violent behavior in patients with schizophrenia. No association was found between delivery mode and impulsive behavior, nor did any articles relate infant feeding mode to violent human behavior. Those studies investigating early antibiotic exposure yielded ambiguous results. The heterogeneity of the data and the different methodologies of the included studies limited the external validity of the results. We found few studies that addressed the possible microbiome involvement in the pathophysiology of impulsive and violent behavior in humans. Our review revealed a gap in knowledge regarding links between the gut microbiome and these extreme behavioral patterns.

Augmented impulsive behavior in febrile seizure-induced mice

Febrile seizure (FS) is one of the most prevalent etiological events in childhood affecting 2-5% of children from 3 months to 5 years old. Debates on whether neurodevelopmental consequences rise in later life following a febrile seizure or not are still ongoing however there is limited evidence of its effect, especially in a laboratory setting. Moreover, the comparative study using both male and female animal models is sparse. To examine the effect of FS on the behavioral features of mice, both sexes of ICR mice were induced with hyperthermic seizures through exposure to an infrared heat lamp. The mice were divided into two groups, one receiving a single febrile seizure at postnatal day 11 (P11) and one receiving three FS at P11, P13, and P15. Starting at P30 the FS-induced mice were subjected to a series of behavioral tests. Mice with seizures showed no locomotor and motor coordination deficits, repetitive, and depressive-like behavior. However, the FS-induced mice showed impulsive-like behavior in both elevated plus maze and cliff avoidance tests, which is more prominent in male mice. A greater number of mice displayed impaired CAT in both males and females in the three-time FS-induced group compared to the single induction group. These results demonstrate that after induction of FS, male mice have a higher susceptibility to consequences of febrile seizure than female mice and recurrent febrile seizure has a higher chance of subsequent disorders associated with decreased anxiety and increased impulsivity. We confirmed the dysregulated expression of impulsivity-related genes such as 5-HT1A and tryptophan hydroxylase 2 from the prefrontal cortices of FS-induced mice implying that the 5-HT system would be one of the mechanisms underlying the increased impulsivity after FS. Taken together, these findings are useful in unveiling future discoveries about the effect of childhood febrile seizure and the mechanism behind it.

How childhood maltreatment alters perception and cognition - the predictive processing account of borderline personality disorder

Borderline personality disorder (BPD) is a severe mental disorder, comprised of heterogeneous psychological and neurobiological pathologies. Here, we propose a predictive processing (PP) account of BPD to integrate these seemingly unrelated pathologies. In particular, we argue that the experience of childhood maltreatment, which is highly prevalent in BPD, leaves a developmental legacy with two facets: first, a coarse-grained, alexithymic model of self and others - leading to a rigidity and inflexibility concerning beliefs about self and others. Second, this developmental legacy leads to a loss of confidence or precision afforded beliefs about the consequences of social behavior. This results in an over reliance on sensory evidence and social feedback, with concomitant lability, impulsivity and hypersensitivity. In terms of PP, people with BPD show a distorted belief updating in response to new information with two opposing manifestations: rapid changes in beliefs and a lack of belief updating despite disconfirmatory evidence. This account of distorted information processing has the potential to explain both the instability (of affect, self-image, and interpersonal relationships) and the rigidity (of beliefs about self and others) which is typical of BPD. At the neurobiological level, we propose that enhanced levels of dopamine are associated with the increased integration of negative social feedback, and we also discuss the hypothesis of an impaired inhibitory control of the prefrontal cortex in the processing of negative social information. Our account may provide a new understanding not only of the clinical aspects of BPD, but also a unifying theory of the corresponding neurobiological pathologies. We conclude by outlining some directions for future research on the behavioral, neurobiological, and computational underpinnings of this model, and point to some clinical implications of it.

Parental alcohol and drug abuse and offspring mortality by age 10: a population-based register study

BACKGROUND

Parental substance abuse (SA) of alcohol and drugs is associated with offspring mortality, including sudden infant death syndrome (SIDS), in infancy, but research on cause-specific mortality and mortality in later childhood is scarce.

METHODS

Using population-based register data on all births in Sweden in 1973-2013 (N = 4.2 million) and Cox regressions, we examined the associations of mother's and father's SA registered between 2 years before and 12 years after the child birth with offspring all-cause and cause-specific mortality in infancy and childhood.

RESULTS

Parental SA was associated with increased offspring all-cause and natural-cause mortality in infancy, but not in the neonatal period, and with external-cause mortality in ages 1-9. Risk of SIDS was 130-280% higher in infants with parental SA compared to infants with no parental SA. Adjusting for parental socioeconomic and immigrant status and severe psychiatric disorders, paternal SA was associated with 66% higher mortality due to communicable diseases and infections in infancy, and both maternal and paternal SA were associated with 40-174% higher mortality due to accidents in infancy and in ages 1-9. The associations between parental SA and offspring mortality were similar for male and female offspring.

CONCLUSIONS

Child mortality is rare in contemporary Sweden, and parental SA has variable associations with elevated offspring mortality throughout the first 10 years of life, excluding the neonatal period, which is indicative of insufficient recognition of children at risk. Preventive measures should be long-term and targeted to both parental and offspring behaviour.

The Implication of 5-HT Receptor Family Members in Aggression, Depression and Suicide: Similarity and Difference

Being different multifactorial forms of psychopathology, aggression, depression and suicidal behavior, which is considered to be violent aggression directed against the self, have principal neurobiological links: preclinical and clinical evidence associates depression, aggression and suicidal behavior with dysregulation in central serotonergic (5-HT) neurotransmission. The implication of different types of 5-HT receptors in the genetic and epigenetic mechanisms of aggression, depression and suicidality has been well recognized. In this review, we consider and compare the orchestra of 5-HT receptors involved in these severe psychopathologies. Specifically, it concentrates on the role of 5-HT_1A, 5-HT_1B, 5-HT_2A, 5-HT_2B, 5-HT_2C, 5-HT₃ and 5-HT₇ receptors in the mechanisms underlying the predisposition to aggression, depression and suicidal behavior. The review provides converging lines of evidence that: (1) depression-related 5-HT receptors include those receptors with pro-depressive properties (5-HT_2A, 5-HT₃ and 5-HT₇) as well as those providing an antidepressant effect (5-HT_1A, 5-HT_1B, 5-HT_2C subtypes). (2) Aggression-related 5-HT receptors are identical to depression-related 5-HT receptors with the exception of 5-HT₇ receptors. Activation of 5-HT_1A, 5-HT_1B, 5-HT_2A, 5-HT_2C receptors attenuate aggressiveness, whereas agonists of 5-HT₃ intensify aggressive behavior.

Specific dopaminergic genetic variants influence impulsivity, cognitive deficit, and disease severity of Indian ADHD probands

BACKGROUND

Impulsivity (Imp), being one of the cardinal symptoms of Attention Deficit Hyperactivity Disorder (ADHD), often leads to inappropriate responses to stimuli. Since the dopaminergic system is the primary target for pharmaceutical intervention in ADHD, we investigated the association between ADHD-related Imp and functional gene variants of the dopamine transporter (SLC6A3) and catechol-O-methyltransferase involved in dopamine clearance.

METHODS AND RESULTS

Indo-Caucasoid families with ADHD probands (N = 217) were recruited based on the Diagnostic and Statistical Manual of Mental Disorders (DSM). Imp of the probands was assessed using the Domain Specific Imp Scale for Children and DSM. Peripheral blood was collected after obtaining informed written consent for participation, genomic DNA was isolated, and target sites were genotyped by DNA sequencing. The association of genetic variants with Imp was examined by the Quantitative trait analysis (QTA) and Analysis of variance (ANOVA). Post-Hoc analysis following QTA and ANOVA showed significant associations of rs2254408, rs2981359, and rs2239393 with different domains of Imp (P < 0.05). Various haplotypic combinations also showed statistically significant associations with Imp (P < 0.05). Multifactor dimensionality reduction models revealed strong effects of the variants on Imp. ADHD probands harboring the risk alleles exhibited a deficit in performance during cognitive assessment. Longitudinal follow-up revealed a significant association of rs2254408 with trait persistence.

CONCLUSION

The present study indicates the influence of the studied genetic variants on ADHD-associated imp, executive deficit, and disease persistence. Thus, these variants may be helpful as predictors for the success of individual therapeutic sessions during cognitive training.

Assessment of Binge-Like Eating of Unsweetened vs. Sweetened Chow Pellets in BALB/c Substrains

Binge eating disorder (BED) is defined as chronic episodes of consuming large amounts of food in less than 2 h. Binge eating disorder poses a serious public health problem, as it increases the risk of obesity, type II diabetes, and heart disease. Binge eating is a highly heritable trait; however, its genetic basis remains largely unexplored. We employed a mouse model for binge eating that focused on identifying heritable differences between inbred substrains in acute and escalated intake of sucrose-sweetened palatable food vs. unsweetened chow pellets in a limited, intermittent access paradigm. In the present study, we examined two genetically similar substrains of BALB/c mice for escalation in food consumption, incubation of craving after a no-food training period, and compulsive-like food consumption in an aversive context. BALB/cJ and BALB/cByJ mice showed comparable levels of acute and escalated consumption of palatable food across training trials. Surprisingly, BALB/cByJ mice also showed binge-like eating of the unsweetened chow pellets similar to the escalation in palatable food intake of both substrains. Finally, we replicated the well-documented decrease in anxiety-like behavior in BALB/cByJ mice in the light-dark conflict test that likely contributed to greater palatable food intake than BALB/cJ in the light arena. To summarize, BALB/cByJ mice show binge-like eating in the presence and absence of sucrose. Possible explanations for the lack of selectivity in binge-like eating across diets (e.g., novelty preference, taste) are discussed.

Factors in the neurodevelopment of negative urgency: Findings from a community-dwelling sample

This study investigated neuroanatomic, genetic, cognitive, sociodemographic and emotional underpinnings of the Negative Urgency subscale of the Urgency, Premeditation, Perseverance, Sensation-Seeking and Positive Urgency Impulsive Behavior Scale in a healthy developmental sample. The goal of the investigation is to contribute to the harmonisation of behavioural, brain and neurogenetic aspects of behavioural self-control. Three domains - (1) Demographic, developmental, psychiatric and cognitive ability; (2) Regional brain volumes (neurobiological); and (3) Genetic variability (single nucleotide polymorphisms) - were examined, and models with relevant predictor variables were selected. Least absolute shrinkage and selection operator and best subset regressions were used to identify sparse models predicting negative urgency scores, which revealed that variables related to emotional regulation and right cingulate volume, as well as single nucleotide polymorphisms in CADM2 and SLC6A4, were associated with negative urgency. Our results contribute to the construct and criterion validity of negative urgency and support the hypothesis that negative urgency is a result of a complex array of influences across domains whose integration furthers developmental psychopathology research.

Heritable variation in locomotion, reward sensitivity and impulsive behaviors in a genetically diverse inbred mouse panel

Drugs of abuse, including alcohol and stimulants like cocaine, produce effects that are subject to individual variability, and genetic variation accounts for at least a portion of those differences. Notably, research in both animal models and human subjects point toward reward sensitivity and impulsivity as being trait characteristics that predict relatively greater positive subjective responses to stimulant drugs. Here we describe use of the eight collaborative cross (CC) founder strains and 38 (reversal learning) or 10 (all other tests) CC strains to examine the heritability of reward sensitivity and impulsivity traits, as well as genetic correlations between these measures and existing addiction-related phenotypes. Strains were all tested for activity in an open field and reward sensitivity (intake of chocolate BOOST®). Mice were then divided into two counterbalanced groups and underwent reversal learning (impulsive action and waiting impulsivity) or delay discounting (impulsive choice). CC and founder mice show significant heritability for impulsive action, impulsive choice, waiting impulsivity, locomotor activity, and reward sensitivity, with each impulsive phenotype determined to be non-correlating, independent traits. This research was conducted within the broader, inter-laboratory effort of the Center for Systems Neurogenetics of Addiction (CSNA) to characterize CC and DO mice for multiple, cocaine abuse related traits. These data will facilitate the discovery of genetic correlations between predictive traits, which will then guide discovery of genes and genetic variants that contribute to addictive behaviors.

Stronger alcohol-violence association when adolescents drink less? Evidence from three Nordic countries

BACKGROUND

Since 2000, adolescents' alcohol use and heavy episodic drinking (HED) have declined in the Nordic countries. However, little is known about corresponding trends in alcohol-related harm and possible changes in the alcohol-harm association. The aims are to examine (i) whether the decline in HED was accompanied by a decline in alcohol-related violence (AV) and (ii) whether the strength of the HED-AV association changed concomitant with the decline.

METHODS

Analysis of data from the European School Survey Project on Alcohol and Other Drugs (ESPAD), conducted among 15-16-year-olds in Iceland, Norway and Sweden in 2007 and 2015 (n = 17 027). Changes in proportions of AV and alcohol use past 12 months, and mean frequency of HED past 30 days were examined using Pearsons χ2-test and F-test, respectively. The HED-AV associations were estimated using logistic regression analysis.

RESULTS

HED and AV proportions decreased from 2007 to 2015 in all countries. Among current drinkers (n = 8927), both HED frequency and AV proportion decreased in Norway (P < 0.001) and remained stable in Iceland. In Sweden, AV decreased (P < 0.001) whereas HED remained stable. The magnitude of the HED-AV association increased in Norway (Beta2015-2007 = 0.145, 95% CI 0.054-0.236), remained the same in Iceland and decreased in Sweden (Beta2015-2007 = -0.082, 95% CI -0.158 to -0.005).

CONCLUSIONS

Among youth in Iceland, Norway and Sweden, heavy episodic drinking and alcohol-related violence declined from 2007 to 2015. Among drinkers, the strength of the alcohol-violence association was moderated by the extent of heavy episodic drinking.

Variation rs6971 in the Translocator Protein Gene (TSPO) is Associated with Aggressiveness and Impulsivity but Not with Anxiety in a Population-Representative Sample of Young Adults

Expression of the 18-kDa translocator protein (TSPO), originally identified as a peripheral benzodiazepine receptor, has been found to be altered in several psychiatric disorders. A common single nucleotide polymorphism (rs6971) in the TSPO gene leads to an amino acid substitution, Ala147Thr, which dramatically alters the affinity with which TSPO binds drug ligands. As cholesterol also binds TSPO in the same transmembrane domain, it is suggested that this substitution may impair the ability of TSPO to bind or import cholesterol, and hence may affect steroid synthesis and hypothalamic-pituitary-adrenal function. The analysis was carried out on older birth cohort (n = 655) of the longitudinal Estonian Children Personality, Behavior and Health Study sample. Anxiety, aggressive behavior, impulsiveness, and history of stressful life events were self-reported in various data collection waves. Psychiatric assessment of lifetime prevalence of anxiety disorders was carried out at 25 years of age by experienced clinical psychologists. TSPO rs6971 was genotyped in all participants. TSPO rs6971 was not associated with self-reported levels of anxiety or lifetime prevalence of anxiety disorders. However, participants homozygous for the minor A allele displayed the highest aggressiveness and dysfunctional impulsivity scores. The positive, adaptive aspect of impulsivity was sensitive to stressful life events, as the AA genotype was associated with functional impulsivity only when the participants had experienced a low number of stressful life events during childhood. TSPO rs6971 polymorphism may be related to development of aggressiveness and impulsivity by adulthood, regardless of the participants' gender.

Impulsivity as an Endophenotype in ADHD: Negative Findings

Impulsivity has a strong genetic component and is considered an endophenotype in many psychiatric disorders. Impulsivity in adult ADHD has become a focus of interest more recently because of its suggested prominence in this age. Objective: This study aimed to access self-reported impulsivity levels in biological parents of ADHD offspring, according to their status: non-ADHD (controls), remitted, nonremitted. Method: Impulsivity levels of 155 parents of ADHD children were compared according to their status using the Barratt Impulsiveness Scale (BIS-11). Results: The ADHD group presented the highest levels of impulsivity compared with all other groups. The remitted ADHD and control groups showed no significant differences in impulsivity levels. Conclusion: Impulsivity tended to remit alongside ADHD symptoms in remitters and to persist in those presenting with the residual form of adult ADHD suggesting it should not be considered as an endophenotype. Only the attentional dimension was impaired, cautioning against Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) impulsivity proposed criteria.

Personality and Genetics Correlations to Risk-Taking Using Quantum Decision Theory in Balloon Analogue Risk Tasks

Genetics and personality can be determined and assessed in individuals, which can be used to predict behaviours in large groups and possibly individually. This report will describe how to use quantum decision theory (QDT) to predict these behaviours. Genetics and personality correlations to risk-taking using QDT in balloon analogue risk tasks (BART) will be covered in this report. The areas of theory covered will be BART, QDT, QDT in BART, personality correlations to risk-taking in BART, genetic correlations to risk-taking in BART, the models used in these theories and a presentation of new models to use these theories together. This article reviews many other primary research articles, which analyses the correlation between genetics/personality and risk-taking behaviour in BART. This report provides models that use impulsivity, venturesomeness, and genetic traits with QDT, to probabilistically predict decisions in risk-taking behaviour.

Less adolescent alcohol and cannabis use: More deviant user groups?

INTRODUCTION AND AIMS

Adolescent drinking and cannabis use in Norway declined in the 2000s, and we tested the assumption that psychosocial problems were more strongly related to substance use when the prevalence was quite low (2012/2013) than when it was considerably higher (2002).

DESIGN AND METHODS

Data stemmed from school surveys of almost 20 000 students aged 14-17 years in 2002 and 2012/2013 in the four largest cities in Norway. We assessed how various deviant behaviours and depressive mood were related to past-year measures on any alcohol intoxication, frequent intoxication (6+ times) and any cannabis use, and tested whether the associations varied significantly by survey year.

RESULTS

The prevalence of any intoxication episodes dropped markedly from 2002 (50%) to 2012/2013 (28%), as did the prevalence of frequent intoxication (29% vs. 10%) and any cannabis use (15% vs. 7%). Deviant behaviours and depressive mood were either more closely related to the drinking outcomes in 2012/2013 than in 2002, or the associations showed no temporal change. None of the associations with cannabis use varied significantly by survey year.

DISCUSSION AND CONCLUSION

The assumption that psychosocial problems correlated more strongly with alcohol and cannabis use in a low-prevalence period (2012/2013) as compared to a high-prevalence period (2002) was partly supported, but only with respect to drinking. The strength of the associations with cannabis use was stable, which may reflect that the proportion reporting any use of the drug was low even in the relatively 'high-prevalence' period.

Self-harm and violent criminality linked with parental death during childhood

BACKGROUND

Adverse health and social outcomes are known to occur more frequently following parental death during childhood, but evidence is lacking for comparing long-term risks of internalised v. externalised harm.

METHODS

This national register-based cohort study consisted of Danish persons born 1970-2000. The Civil Registration System and National Causes of Death Register were linked to ascertain parental deaths by cause before cohort members' 15th birthdays. From age 15 years, hospital-treated self-harm episodes were ascertained through linkage to the National Patient Register and the Psychiatric Central Research Register, and violent crimes were identified via linkage to the National Crime Register. Hazard ratio and cumulative incidence values were estimated.

RESULTS

Self-harm and violent criminality risks were elevated following parental death during childhood. Covariate adjustment for gender, birth year and first-degree relatives' mental illnesses attenuated these associations, although significantly heightened risks persisted. The estimated hazard ratios did not differ greatly according to which parent died, but losing both parents conferred particularly large risk increases. Risks for both adverse outcomes were higher in relation to unnatural v. natural parental death; violent criminality risk was especially raised among individuals exposed to parental death by unnatural causes other than suicide. The association was strongest when pre-school age children experienced parental death.

CONCLUSIONS

Effective early intervention is needed to help youngsters who have experienced the death of one or both parents to develop immediate and sustained coping strategies. Enhanced cooperation between health and social services and criminal justice agencies may mitigate risks for these two destructive behaviours.

Impulsivity is a heritable trait in rodents and associated with a novel quantitative trait locus on chromosome 1

Impulsivity describes the tendency to act prematurely without appropriate foresight and is symptomatic of a number of neuropsychiatric disorders. Although a number of genes for impulsivity have been identified, no study to date has carried out an unbiased, genome-wide approach to identify genetic markers associated with impulsivity in experimental animals. Herein we report a linkage study of a six-generational pedigree of adult rats phenotyped for one dimension of impulsivity, namely premature responding on the five-choice serial reaction time task, combined with genome wide sequencing and transcriptome analysis to identify candidate genes associated with the expression of the impulsivity trait. Premature responding was found to be heritable (h² = 13-16%), with significant linkage (LOD 5.2) identified on chromosome 1. Fine mapping of this locus identified a number of polymorphic candidate genes, however only one, beta haemoglobin, was differentially expressed in both the founder strain and F6 generation. These findings provide novel insights into the genetic substrates and putative neurobiological mechanisms of impulsivity with broader translational relevance for impulsivity-related disorders in humans.

Longitudinal associations between mothers' and fathers' anger/irritability expressiveness, harsh parenting, and adolescents' socioemotional functioning in nine countries

The present study examines parents' self-efficacy about anger regulation and irritability as predictors of harsh parenting and adolescent children's irritability (i.e., mediators), which in turn were examined as predictors of adolescents' externalizing and internalizing problems. Mothers, fathers, and adolescents (N = 1,298 families) from 12 cultural groups in 9 countries (China, Colombia, Italy, Jordan, Kenya, Philippines, Sweden, Thailand, and United States) were interviewed when children were about 13 years old and again 1 and 2 years later. Models were examined separately for mothers and fathers. Overall, cross-cultural similarities emerged in the associations of both mothers' and fathers' irritability, as well as of mothers' self-efficacy about anger regulation, with subsequent maternal harsh parenting and adolescent irritability, and in the associations of the latter variables with adolescents' internalizing and externalizing problems. The findings suggest that processes linking mothers' and fathers' emotion socialization and emotionality in diverse cultures to adolescent problem behaviors are somewhat similar. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Genetic contribution to the phenotypic correlation between trait impulsivity and resting-state functional connectivity of the amygdala and its subregions

Trait impulsivity, a predisposition to respond to stimuli without regard for the potentially negative consequences, contributes to many maladaptive behaviors. Studies have shown that both genetic factors and interregional functional interactions underlie trait impulsivity. However, whether common genes contribute to both trait impulsivity and its neural basis is still unknown. This study investigated the phenotypic correlations between trait impulsivity and the resting-state functional connectivity (rsFC) of the amygdala as well as its subregions and the genetic contribution to the phenotypic correlations. By recruiting a sample of 292 twins in late adolescence and young adulthood, we found that trait impulsivity was positively correlated with the rsFC between the left full amygdala and the right dorsolateral prefrontal cortex (DLPFC). Further analyses on the subregions of the amygdala showed that trait impulsivity was positively correlated with the rsFCs between the left basolateral (BL) amygdala and both the right DLPFC and the right inferior frontal gyrus and with the rsFCs between the right superficial (SF) amygdala and both the dorsal anterior cingulate cortex and right anterior insula. Bivariate genetic modelling analyses found genetic overlaps between trait impulsivity and the rsFC of the left full amygdala or the left BL amygdala with the right DLPFC. The proportions of phenotypic associations accounted for by overlapping genes were 82% and 60%, respectively. These results provide evidence for the genetic overlap between trait impulsivity and the intrinsic brain functional connectivity centered at the amygdala and especially at its BL subregion.

The neurobiology of impulsivity and substance use disorders: implications for treatment

Impulsivity is strongly associated with substance use disorders (SUDs). Our review discusses impulsivity as an underlying vulnerability marker for SUDs, and treatment of co-occurring impulsivity in SUDs. Three factors should be considered for the complex relationship between impulsivity and a SUD: (1) the trait effect of impulsivity, centering on decreased cognitive and response inhibition, (2) the state effect resulting from either acute or chronic substance use on brain structure and function, and (3) the genetic and environmental factors (e.g., age and sex) may influence impulsive behavior associated with SUDs. Both subjective and objective measures are used to assess impulsivity. Together, treatment developments (pharmacological, behavioral, and neurophysiological) should consider these clinically relevant dimensions assessed by a variety of measures, which have implications for treatment matching in individuals with SUD. Despite its heterogeneity, impulsivity is a marker associated with SUDs and may be understood as an imbalance of bottom-up and top-down neural systems. Further investigation of these relationships may lead to more effective SUD treatments.

Gambling disorder

Gambling disorder is characterized by a persistent, recurrent pattern of gambling that is associated with substantial distress or impairment. The prevalence of gambling disorder has been estimated at 0.5% of the adult population in the United States, with comparable or slightly higher estimates in other countries. The aetiology of gambling disorder is complex, with implicated genetic and environmental factors. Neurobiological studies have implicated cortico-striato-limbic structures and circuits in the pathophysiology of this disorder. Individuals with gambling disorder often go unrecognized and untreated, including within clinical settings. Gambling disorder frequently co-occurs with other conditions, particularly other psychiatric disorders. Behavioural interventions, particularly cognitive-behavioural therapy but also motivational interviewing and Gamblers Anonymous, are supported in the treatment of gambling disorder. No pharmacological therapy has a formal indication for the treatment of gambling disorder, although placebo-controlled trials suggest that some medications, such as opioid-receptor antagonists, may be helpful. Given the associations with poor quality of life and suicide, improved identification, prevention, policy and treatment efforts are needed to help people with gambling disorder.

A Systematic Review on the Influences of Neurotoxicological Xenobiotic Compounds on Inhibitory Control

Background: Impulsive and compulsive traits represent a variety of maladaptive behaviors defined by the difficulties to stop an improper response and the control of a repeated behavioral pattern without sensitivity to changing contingencies, respectively. Otherwise, human beings are continuously exposed to plenty neurotoxicological agents which have been systematically linked to attentional, learning, and memory dysfunctions, both preclinical and clinical studies. Interestingly, the link between both impulsive and compulsive behaviors and the exposure to the most important xenobiotic compounds have been extensively developed; although the information has been rarely summarized. For this, the present systematic review schedule and analyze in depth the most important works relating different subtypes of the above-mentioned behaviors with 4 of the most important xenobiotic compounds: Lead (Pb), Methylmercury (MeHg), Polychlorinated biphenyls (PCB), and Organophosphates (OP) in both preclinical and clinical models.

Methods: Systematic search strategy on PubMed databases was developed, and the most important information was structured both in text and in separate tables based on rigorous methodological quality assessment.

Results: For Lead, Methylmercury, Polychlorinated biphenyls and organophosphates, a total of 44 (31 preclinical), 34 (21), 38 (23), and 30 (17) studies were accepted for systematic synthesis, respectively. All the compounds showed an important empirical support on their role in the modulation of impulsive and, in lesser degree, compulsive traits, stronger and more solid in animal models with inconclusive results in humans in some cases (i.e., MeHg). However, preclinical and clinical studies have systematically focused on different subtypes of the above-mentioned behaviors, as well as impulsive choice or habit conformations have been rarely studied.

Discussion: The strong empirical support in preclinical studies contrasts with the lack of connection between preclinical and clinical models, as well as the different methodologies used. Further research should be focused on dissipate these differences as well as deeply study impulsive choice, decision making, risk taking, and cognitive flexibility, both in experimental animals and humans.

Borderline personality disorder and emotion dysregulation

Borderline personality disorder (BPD) is a severe and complex disorder characterized by instability across many life domains, including interpersonal relations, behavior, and emotions. A core feature and contributor to BPD, emotion dysegulation (ED), consists of deficits in the ability to regulate emotions in a manner that allows the individual to pursue important goals or behave effectively in various contexts. Biosocial developmental models of BPD have emphasized a transaction of environmental conditions (e.g., invalidating environments and adverse childhood experiences) with key genetically linked vulnerabilities (e.g., impulsivity and emotional vulnerability) in the development of ED and BPD. Emerging evidence has begun to highlight the complex, heterotypic pathways to the development of BPD, with key heritable vulnerability factors possibly interacting with aspects of the rearing environment to produce worsening ED and an adolescent trajectory consisting of self-damaging behaviors and eventual BPD. Adults with BPD have shown evidence of a variety of cognitive, physiological, and behavioral characteristics of ED. As the precursors to the development of ED and BPD have become clearer, prevention and treatment efforts hold great promise for reducing the long-term suffering, functional impairment, and considerable societal costs associated with BPD.

A biopsychosocial approach to processes and pathways in the development of overweight and obesity in childhood: Insights from developmental theory and research

Childhood obesity has reached alarming proportions in many countries. There is consensus that both biological (especially genetic) and environmental (including psychosocial) factors contribute to weight gain and obesity in childhood. Research has identified extensive risk or predictive factors for childhood obesity from both of these domains. There is less consensus about the developmental processes or pathways showing how these risk factors lead to overweigh/obesity (OW/OB) in childhood. We outline a biopsychosocial process model of the development of OW/OB in childhood. The model and associated scholarship from developmental theory and research guide an analysis of research on OW/OB in childhood. The model incorporates biological factors such as genetic predispositions or susceptibility genes, temperament, and homeostatic and allostatic processes with the psychosocial and behavioral factors of parenting, parental feeding practices, child appetitive traits, food liking, food intakes, and energy expenditure. There is an emphasis on bidirectional and transactional processes linking child biology and behavior with psychosocial processes and environment. Insights from developmental theory and research include implications for conceptualization, measurement, research design, and possible multiple pathways to OW/OB. Understanding the developmental processes and pathways involved in childhood OW/OB should contribute to more targeted prevention and intervention strategies in childhood.

Common Genetic Influences on Impulsivity Facets are Related to Goal Management, Psychopathology, and Personality

In this study, we characterized the genetic/environmental commonality and heterogeneity of impulsivity facets and tested the hypothesis that goal-management is central to their common variance. 764 young-adult twins completed the UPPS-P Impulsive Behavior Scale and measures of goal management, personality, and psychopathology. We found common genetic influences across all impulsivity facets except sensation seeking. These impulsivity genetic influences explained 40.0% of variance in goal-management ability. Other results supported three hypotheses concerning heterogeneity: that sensation seeking is independent of other facets, that urgency is more related to psychopathology than lack of premeditation, and that lack of perseverance is more similar to urgency than lack of premeditation. Thus, impulsivity facets show considerable heterogeneity in addition to common variation related to goal-management abilities.

Genome-Wide Association Studies of Impulsive Personality Traits (BIS-11 and UPPS-P) and Drug Experimentation in up to 22,861 Adult Research Participants Identify Loci in the CACNA1I and CADM2 genes

Impulsive personality traits are complex heritable traits that are governed by frontal-subcortical circuits and are associated with numerous neuropsychiatric disorders, particularly drug abuse and attention-deficit/hyperactivity disorder (ADHD). In collaboration with the genetics company 23andMe, we performed 10 genome-wide association studies on measures of impulsive personality traits [the short version of the UPPS-P Impulsive Behavior Scale, and the Barratt Impulsiveness Scale (BIS-11)] and drug experimentation (the number of drug classes an individual had tried in their lifetime) in up to 22,861 male and female adult human research participants of European ancestry. Impulsive personality traits and drug experimentation showed single nucleotide polymorphism heritabilities that ranged from 5 to 11%. Genetic variants in the CADM2 locus were significantly associated with UPPS-P Sensation Seeking (p = 8.3 × 10^-9, rs139528938) and showed a suggestive association with Drug Experimentation (p = 3.0 × 10^-7, rs2163971; r ² = 0.68 with rs139528938). Furthermore, genetic variants in the CACNA1I locus were significantly associated with UPPS-P Negative Urgency (p = 3.8 × 10^-8; rs199694726). The role of these genes was supported by single variant, gene- and transcriptome-based analyses. Multiple subscales from both UPPS-P and BIS showed strong genetic correlations (>0.5) with Drug Experimentation and other substance use traits measured in independent cohorts, including smoking initiation, and lifetime cannabis use. Several UPPS-P and BIS subscales were genetically correlated with ADHD (r _g = 0.30-0.51), supporting their validity as endophenotypes. Our findings demonstrate a role for common genetic contributions to individual differences in impulsivity. Furthermore, our study is the first to provide a genetic dissection of the relationship between different types of impulsive personality traits and various psychiatric disorders.SIGNIFICANCE STATEMENT Impulsive personality traits (IPTs) are heritable traits that are governed by frontal-subcortical circuits and are associated with neuropsychiatric disorders, particularly substance use disorders. We have performed genome-wide association studies of IPTs to identify regions and genes that account for this heritable variation. IPTs and drug experimentation were modestly heritable (5-11%). We identified an association between single nucleotide polymorphisms in CADM2 and both sensation seeking and drug experimentation; and between variants in CACNA1I and negative urgency. The role of these genes was supported by single variant, gene- and transcriptome-based analyses. This study provides evidence that impulsivity can be genetically separated into distinct components. We showed that IPT are genetically associated with substance use and ADHD, suggesting impulsivity is an endophenotype contributing to these psychiatric conditions.

The Interactive Effects of Parental Knowledge with Impulsivity and Sensation Seeking in Adolescent Substance Use

This study examined whether interactions of parental knowledge of adolescent's whereabouts with impulsivity and sensation seeking in the prediction of adolescent substance use supported the diathesis-stress or differential susceptibility model in 230 15-year old adolescents (53% girls). Interactions between impulsivity and parental knowledge supported the diathesis-stress model with high impulsivity as a vulnerability factor: when impulsivity was higher, low levels of parental knowledge were associated with higher levels of substance use. Interactions between sensation seeking and parental knowledge supported differential susceptibility with low sensation seeking as a susceptibility factor; low parental knowledge was associated with higher substance use and high parental knowledge with lower substance use when sensation seeking was lower. Our results show that impulsivity and sensation seeking should be considered independently. Results support previous research suggesting that impulsivity in adolescence may act as a vulnerability factor and suggests that low sensation seeking may be a susceptibility factor.

Alexithymia, Impulsivity, and Reward Sensitivity in Young Adult University Student Children of Alcoholics

BACKGROUND AND OBJECTIVES

Personality traits previously known as risk factors for alcohol use disorder (AUD) were assessed in 29 young adult children of alcoholics (COAs) and 68 young adult children of nonalcoholics (non-COAs). Male and female university students (M_age = 22.11 years) completed questions pertaining to demographics and alcohol use, and the Children of Alcoholics Screening Test; Toronto Alexithymia Scale; Barratt Impulsiveness Scale; Sensitivity to Punishment and Sensitivity to Reward Questionnaire; and Depression Anxiety Stress Scales.

RESULTS

Results indicated that personality traits of alexithymia, reward sensitivity, and impulsivity, as well as negative moods, were significantly elevated in COAs compared to non-COAs, independent of current alcohol consumption and drinking history.

CONCLUSIONS

Findings are consistent with familial transmission of AUD-associated personality traits in COAs, presumably via influences of genetics and/or familial environment.

Nurturing Our Better Nature: A Proposal for Cognitive Integrity as a Foundation for Autonomous Living

As we account for the genetic and environmental influences on morally-relevant character traits like intellectual honesty, industriousness, and self-control, do we risk becoming ever less accountable to ourselves? Behavioral genetic research suggests that about half the variance in such character traits is likely attributable to heredity, and a small fraction to the shared family environment. The remaining 40-60% is explained by neither genes nor family upbringing. This raises the question: how active a role can individuals play in shaping their own character? What, if anything, can and should one do to take responsibility for the kind of person one becomes? This paper sketches a novel theoretical proposal for addressing these questions, by drawing on several previously disparate lines of research within behavior genetics, philosophy, and experimental psychology. Our core proposal concerns the metacognitive capacity to engage in active, reality-based cognition, as opposed to passive, stimulus-driven processing or an active pretense at cognition (i.e., self-deception). We review arguments and evidence indicating that human beings both can and should exercise this capacity, which we have termed "cognitive integrity." We argue that doing so can in a certain sense "set us free" of our genetic and environmental influences-not by rendering them irrelevant, but by giving us the awareness and motivation to manage them more responsibly. This perspective has important implications for guiding the development of psychosocial interventions, and for informing how we direct ourselves more generally, both as individuals and as a society.

Phytochemistry and pharmacology of anti-depressant medicinal plants: A review

Stress renders an individual to experience mental pressure and exhaustion which brings about feelings of anxiety, depression, anger and/or other negative emotions. Depression affects a person's state of mind, behaviour, health and is often associated with suicide. The use of anti-depressant drugs as therapeutic agents is associated with symptoms such as, delayed onset of action, side-effects, drug-drug and dietary interactions, sexual dysfunction, cardiac toxicity, etc. Thus, there is need to target these issues and improve current treatment options. Medicinal plants have long been used in discovering novel treatment strategies and compounds with promising roles in treating various disease conditions. There has been an increase, worldwide, in the use of medicinal plants and herbs for developing nutraceuticals for treatment of depression and other psychiatric disorders. Medicinal plants in their natural forms are valuable as they are rich in various phytochemical compounds. These phytochemical compounds have pharmacological roles in treating various diseases conditions; apart from being widely available in nature and commercially beneficial. The phytochemical compounds in plants are constantly being explored through various experimental studies to determine the molecular basis of how medicinal plants work in relation to drugs and diseases and to develop neutraceuticals for improving conditions. This review summarizes 110 medicinal plants and their phytochemical constituents that have been shown to possess anti-depressant activity. This review also highlights the various mechanisms of anti-depressant action of some of these plants and their plant parts like roots, stem, leaves, flowers, fruit or whole plant; phytochemical compounds showing anti-depressant activity such flavanoids, steroids, saponins, sugars, lectins, alkaloids, etc.; and various anti-depressant screening models used such as tail suspension test, forced swim test, chronic unpredictable stress test, sucrose preference test, monoamine oxidase inhibition assay, learned helplessness test, open field test, hole board test, etc. However, mechanistic evaluation of many of these plants still needs to be investigated and explored.