Testosterone as a biological marker in psychopathy and alcoholism

Raging Hormones: Why Age-Based Etiological Conceptualizations of the Development of Antisocial Behavior Are Insufficient

Developmental science, particularly developmental neuroscience, has substantially influenced the modern legal system. However, this science has typically failed to consider the role of puberty and pubertal hormones on development when considering antisocial behavior. This review describes major theoretical positions on the developmental neuroscience of antisocial behavior and highlights where basic developmental neuroscience suggests that the role of puberty and pubertal hormones should be considered. The implications of the current state of the science with respect to developmental neuroscience is considered, particularly what is known in light of development beyond puberty. This review shows that development continues to an older age for many youth than the legal system typically acknowledges. The plasticity of the brain that this continued development implies has implications for the outcome of interventions in the legal system in ways that have not been explored. Future directions for both developmental scientists and legal professions are recommended.

Alcohol and Prostate Cancer: Time to Draw Conclusions

It has been a long-standing debate in the research and medical societies whether alcohol consumption is linked to the risk of prostate cancer (PCa). Many comprehensive studies from different geographical areas and nationalities have shown that moderate and heavy drinking is positively correlated with the development of PCa. Nevertheless, some observations could not confirm that such a correlation exists; some even suggest that wine consumption could prevent or slow prostate tumor growth. Here, we have rigorously analyzed the evidence both for and against the role of alcohol in PCa development. We found that many of the epidemiological studies did not consider other, potentially critical, factors, including diet (especially, low intake of fish, vegetables and linoleic acid, and excessive use of red meat), smoking, family history of PCa, low physical activity, history of high sexual activities especially with early age of first intercourse, and sexually transmitted infections. In addition, discrepancies between observations come from selectivity criteria for control groups, questionnaires about the type and dosage of alcohol, and misreported alcohol consumption. The lifetime history of alcohol consumption is critical given that a prostate tumor is typically slow-growing; however, many epidemiological observations that show no association monitored only current or relatively recent drinking status. Nevertheless, the overall conclusion is that high alcohol intake, especially binge drinking, is associated with increased risk for PCa, and this effect is not limited to any type of beverage. Alcohol consumption is also directly linked to PCa lethality as it may accelerate the growth of prostate tumors and significantly shorten the time for the progression to metastatic PCa. Thus, we recommend immediately quitting alcohol for patients diagnosed with PCa. We discuss the features of alcohol metabolism in the prostate tissue and the damaging effect of ethanol metabolites on intracellular organization and trafficking. In addition, we review the impact of alcohol consumption on prostate-specific antigen level and the risk for benign prostatic hyperplasia. Lastly, we highlight the known mechanisms of alcohol interference in prostate carcinogenesis and the possible side effects of alcohol during androgen deprivation therapy.

The role of psychopathic traits, social anxiety and cortisol in social approach avoidance tendencies

Social anxiety and psychopathy have conceptually been linked to nearly opposite emotional, behavioral and endocrinological endophenotypes, representing social fearfulness and fearlessness, respectively. Although such a dimensional view has theoretical and practical implications, no study has directly compared social anxiety and psychopathy in terms of emotional experiences, relevant hormones (i.e. cortisol, testosterone) and behavioral tendencies (i.e. social approach-avoidance). Therefore, the present study examined 1) whether self-reported social anxiety and psychopathic traits are indeed anticorrelated, and 2) whether social anxiety, psychopathic traits, cortisol, testosterone and their interplay are differentially linked to social approach-avoidance tendencies. In a well-powered study, a sample of 196 healthy female participants, we assessed self-reported emotional and behavioral tendencies of social fear (i.e. social anxiety and social avoidance) and psychopathic traits (i.e. Factor I [interpersonal-affective deficit] and Factor II [impulsive behavior]). Furthermore, hormone levels were assessed, and approach-avoidance tendencies towards emotional (angry, happy) facial expressions were measured by means of a joystick reaction time task. Results confirmed that self-reported emotional tendencies of social anxiety and psychopathy Factor I (interpersonal-affective deficit) correlated negatively, but self-reported behavioral tendencies (social avoidance and psychopathy Factor II [impulsive behavior]) correlated positively. Furthermore, Structural Equation Modelling demonstrated that participants with higher social anxiety and higher cortisol levels showed an avoidance tendency towards happy faces, while participants with higher psychopathic traits showed an approach tendency towards angry faces. In sum, the notion that social anxiety and psychopathic traits are opposing ends of one dimension was supported only in terms of self-reported emotional experiences, but a comparable relationship with regard to behavioral and endocrinological aspects is debatable. The current findings stress the necessity to study emotional, endocrinological and behavioral factors in unison in order to better understand the shared and distinctive mechanisms of social anxiety and psychopathic traits.

Sex differences in progestogen- and androgen-derived neurosteroids in vulnerability to alcohol and stress-related disorders

Stress and trauma exposure disturbs stress regulation systems and thus increases the vulnerability for stress-related disorders which are characterized by negative affect, including major depressive disorder, anxiety disorders and posttraumatic stress disorder. Similarly, stress and trauma exposure results in increased vulnerability to problematic alcohol use and alcohol use disorder, especially among women, who are more likely to drink to cope with negative affect than their male counterparts. Given these associations, the relationship between stress-related disorders and alcohol use is generally stronger among women leading to complex comorbidities across these disorders and alcohol misuse. This review highlights the therapeutic potential for progestogen- and androgen-derived neurosteroids, which affect both stress- and alcohol-related disorders, to target the overlapping symptoms related to negative affect. This article is part of the special issue on 'Vulnerabilities to Substance Abuse.'

Evaluating the genetic effects of sex hormone traits on the development of mental traits: a polygenic score analysis and gene-environment-wide interaction study in UK Biobank cohort

OBJECTIVE

To evaluate the genetic effects of sex hormone traits on the development of mental traits in middle-aged adults.

METHODS

The SNPs associated with sex hormone traits were derived from a two-stage genome-wide association study (GWAS). Four sex hormone traits were selected in the current study, including sex hormone-binding globulin (SHBG), testosterone, bioavailable testosterone and estradiol. The polygenic risk score (PRS) of sex hormone traits were calculated from individual-level genotype data of the United Kingdom (UK) Biobank cohort. We then used logistic and linear regression models to assess the associations between individual PRS of sex hormone traits and the frequency of alcohol consumption, anxiety, intelligence and so on. Finally, gene-environment-wide interaction study (GEWIS) was performed to detect novel candidate genes interacting with the sex hormone traits on the development of fluid intelligence and the frequency of smoking and alcohol consumption by PLINK2.0.

RESULTS

We observed positive association between SHBG and the frequency of alcohol consumption (b = 0.0101, p = 3.84 × 10^-11) in middle-aged males and females. In addition, estradiol was positively associated with the frequency of alcohol consumption (b = 0.0128, p = 1.96 × 10^-8) in middle-aged males. Moreover, bioavailable testosterone was associated with the fluid intelligence (b = - 0.0136, p = 5.74 × 10^-5) in middle-aged females. Finally, GEWIS identified one significant loci, Tenascin R (TNR) (rs34633780, p = 3.45 × 10^-8) interacting with total testosterone for fluid intelligence.

CONCLUSION

Our study results support the genetic effects of sex hormone traits on the development of intelligence and the frequency of alcohol consumption in middle-aged adults in UK.

Albumin is a secret factor involved in multidirectional interactions among the serotoninergic, immune and endocrine systems that supervises the mechanism of CYP1A and CYP3A regulation in the liver

This review focuses on albumin, which is involved in multidirectional interactions among the immune, endocrine and serotoninergic systems and supervises the regulation of cytochrome P450 (CYP) isoforms under conditions of both normal liver function and liver insufficiency. Special attention is paid to albumin, thyroid hormones, testosterone and tryptophan hydroxylase in these interactions as well as their potential roles in liver regeneration. The association of these factors with inflammation and the modification of the mechanism of hepatic drug-metabolizing CYP isoform regulation are also presented because changes in the expression of CYP isoforms in the liver may result in subsequent changes to a marker substance used for testing CYP activity, thus providing a simple way to control the liver regeneration process or the dangerous stimulation of hepatocarcinogenesis.

Hormonal responses in gambling versus alcohol abuse: A review of human studies

The endocrine system plays an essential role in communication between various organs of the body to maintain homeostasis. Both substance use disorders (SUDs) and non-substance abuse disrupt this system and lead to hormonal dysregulations. Here, we focus on the comparison between the function of the endocrine system in gambling disorders and alcohol addiction to understand the commonalities and differences in their neurobiological and psychological underpinnings. We review human research to compare findings on gambling addiction and alcohol dependence pertaining to the dynamic interplay between testosterone and cortisol. Understanding and classifying similarities in hormonal responses between behavioural addiction and SUDs may facilitate development of treatments and therapeutic interventions across different types of addictive disorders, while describing differences may shed light on therapeutic interventions for specific disorders. Although research on gambling addiction is in its infancy, such evaluation may still have a positive effect for addiction research, thereby stimulating discovery of "crossover" pharmacotherapies with benefits for both SUDs and nonsubstance addictions.

Sex hormones in alcohol consumption: a systematic review of evidence

Sex hormones play an important role in establishing sex‐distinctive brain structural and functional variations that could contribute to the sex differences in alcohol consumption behavior. Here, we systematically reviewed articles that studied sex hormone impacts on alcohol consumption and alcohol use disorder (AUD). An extensive literature search conducted in MEDLINE, PubMed, Scopus and CINAHL databases identified 776 articles, which were then evaluated for pre‐specified criteria for relevance and quality assurance. A total of 50 articles, including 19 human studies and 31 animal studies, were selected for this review. Existing evidence supports the association of increased testosterone level and increased risk for alcohol use and AUD in males but results are inconclusive in females. In contrast, the evidence supports the association of increased estrogen level and increased alcohol use in females, with mixed findings reported in males. Much less is known about the impact of progestins on alcohol use and misuse in human subjects. Future observational and experimental studies conducted in both sexes with a comprehensive hormone panel are needed to elucidate the impact of the interplay between various sex hormone levels during various developmental stages on alcohol use‐related phenotypes and AUD.

Dual-hormone regulation of psychopathy: Evidence from mass spectrometry

Previous work suggests that testosterone and cortisol interactively predict psychopathy. This effect represents a reversal of the established dual-hormone hypothesis, whereby testosterone is positively correlated with psychopathic traits, but only among individuals with elevated cortisol concentrations. This study aims to replicate the dual-hormone moderation of psychopathy in two independent samples. Enzyme-linked immunoassays (ELISAs) were used to assess cortisol across both samples and testosterone in Sample 1 (n = 165, 100% males). To address recent criticism of ELISAs and potentially extend these findings to women, testosterone concentrations were determined by liquid chromatography tandem mass spectrometry (LC-MS/MS) in Sample 2 (n = 213, 44.1% males). We found conflicting evidence of the dual-hormone moderation of psychopathic traits. Although results were non-significant in Sample 1, a reversal of the dual-hormone hypothesis was found in Sample 2, in which testosterone was positively correlated with psychopathic traits, but only among individuals with high cortisol. This replication provides mixed support for less common reversals to the dual-hormone hypothesis. These findings emphasize the importance of using LC-MS/MS to measure testosterone and adds to the growing body of work on the relationship between hormones and psychopathology in general.

Preliminary Study of Testosterone and Empathy in Determining Recidivism and Antisocial Behavior

Recidivism, repeated criminal behavior after conviction and correction of prior offenses, is a costly problem across the nation. However, the contribution of empathy in determining the risk of recidivism has received limited attention, although lack of empathy has been related to antisocial personality disorder in various studies. Studies linked testosterone to aggression, antisocial behavior, and criminality, and evidence support hormonal connections between empathy and aggression. Adult male prison inmates convicted of violent or nonviolent offenses were included in a cross-sectional study of empathy, antisocial behavior, salivary testosterone, and recidivism. Subjects underwent criminal history, Empathy Quotient, Levenson Self-Report Psychopathy Scale, Beck Depression Inventory, Spielberger State-Trait Anxiety Inventory, and salivary testosterone assays. Bivariate analyses indicated multiple correlations between variables. Multivariate modeling analyses found a significant relationship between self-reported conviction number and psychopathy scale score (p = 0.013). These preliminary results suggest avenues of investigation of factors contributing to recidivism risk.

A hormonal approach to anti-social behaviour

BACKGROUND

Altered levels of cortisol and testosterone have previously been associated with anti-social personality disorder (ASPD) and psychopathy, but there is some conflicting evidence as to how characteristic these findings are.

AIM

To test the hypothesis that diurnal fluctuations in cortisol and/or testosterone will differentiate ASPD and psychopathy among male forensic psychiatric inpatients and distinguish both groups from healthy men not in treatment.

METHODS

One hundred and sixty-six men participated: 81 patients with ASPD, 42 of whom had a Psychopathy Checklist-Revised (PCL-R) score of 26 or more and 39 with a score of 25 or less, 51 forensic hospital employees and 34 general population men. None in the latter two groups had abnormal personality traits. For each person, diurnal cortisol and testosterone saliva samples were collected.

RESULTS

Both patient groups and the forensic hospital employees showed significantly higher diurnal testosterone levels than the general population, community-based men. The community men showed significantly lower values in their diurnal cortisol variation than the ASPD and psychopathy groups but, in this, were similar to the forensic employee group. Neither cortisol nor testosterone levels differentiated the higher from lower Psychopathy Checklist-Revised scorers.

CONCLUSIONS

We replicated findings of diurnal testosterone deficiencies among men with psychopathy and ASPD, but we were unable to differentiate patients groups from each other or from the hospital employees on cortisol measures. This suggests a case for more research with more diverse comparison groups and more differentiation of personality traits before drawing definitive conclusions about distinctive hormonal patterns among men with psychopathy, as external environmental variables may prove more influential than previously suspected. Copyright © 2015 John Wiley & Sons, Ltd.

The Relationship between Aggression and Serum Thyroid Hormone Level in Individuals Diagnosed with Antisocial Personality Disorder

INTRODUCTION

Aggression is one of the leading clinical characteristics of antisocial personality disorder (APD). Studies aiming to clarify and control the biological basis of aggression are ongoing. Thyroid hormones have been indicated to play a role in the development of aggression. The aim of this study was to examine the level of aggression and serum thyroid hormone in a sample of APD and to make contributions to this field with the current findings.

METHODS

The sample consisted of 96 subjects with a diagnosis of APD and 97 subjects as a control group. Structured Clinical Interview for DSM-IV Axis (SCID) 1 and 2 were used for the diagnosis, and the Buss-Perry Aggression Questionnaire was administered. Based on criminal patterns, the APD group was then divided into two subgroups: "criminal" and "noncriminal" APD groups. The day after the interview, after one night of fasting, blood was collected from the subjects between 7:00 a.m. and 9:00 a.m.. Thyroid function tests and other biochemical analyses related to the confounding variables were also administered. The study group and the control group were compared in terms of their aggression scores and thyroid hormone levels.

RESULTS

The mean score of free T3 level in the criminal APD group was found to be significantly higher than that in the noncriminal APD group. APD subjects with higher free T3 levels also had higher aggression scores. In the noncriminal APD group, as serum free T3 and T4 levels increased, there was also an increment in the aggression scores. However, in the criminal APD group, there was no significant correlation between thyroid hormone levels and aggression.

CONCLUSION

The findings of this study indicated that criminal and noncriminal APD groups actually show different properties.

Testosterone Reduces Conscious Detection of Signals Serving Social Correction

Elevated levels of testosterone have repeatedly been associated with antisocial behavior, but the psychobiological mechanisms underlying this effect are unknown. However, testosterone is evidently capable of altering the processing of facial threat, and facial signals of fear and anger serve sociality through their higher-level empathy-provoking and socially corrective properties. We investigated the hypothesis that testosterone predisposes people to antisocial behavior by reducing conscious recognition of facial threat. In a within-subjects design, testosterone (0.5 mg) or placebo was administered to 16 female volunteers. Afterward, a task with morphed stimuli indexed their sensitivity for consciously recognizing the facial expressions of threat (disgust, fear, and anger) and nonthreat (surprise, sadness, and happiness). Testosterone induced a significant reduction in the conscious recognition of facial threat overall. Separate analyses for the three categories of threat faces indicated that this effect was reliable for angry facial expressions exclusively. This testosterone-induced impairment in the conscious detection of the socially corrective facial signal of anger may predispose individuals to antisocial behavior.

The Ratio of 2nd to 4th Digit Length in Korean Alcohol-dependent Patients

Objective

The ratio of 2nd to 4th digit length (2D:4D) is a sexually dimorphic trait. Men have a relatively shorter second digit than fourth digit. This ratio is thought to be influenced by higher prenatal testosterone level or greater sensitivity to androgen. The purpose of this study is to investigate the relationship between alcohol dependence and 2D:4D in a Korean sample and whether 2D:4D can be a biologic marker in alcohol dependence.

Methods

In this study, we recruited 87 male patients with alcohol dependence from the alcohol center of one psychiatric hospital and 52 healthy male volunteers who were all employees in the same hospital as controls. We captured images of the right and left hands of patients and controls using a scanner and extracted data with a graphics program. We measured the 2D:4D of each hand and compared the alcohol dependence group with the control group. We analyzed these ratios using an independent-samples t-test.

Results

The mean 2D:4D of patients was 0.934 (right hand) and 0.942 (left hand), while the mean 2D:4D of controls was 0.956 (right hand) and 0.958 (left hand). Values for both hands were significantly lower for patients than controls (p<0.001, right hand; p=0.004, left hand).

Conclusion

Patients who are alcohol dependent have a significantly lower 2D:4D than controls, similar to the results of previous studies, which suggest that a higher prenatal testosterone level in the gonadal period is related to alcoholism. Furthermore, 2D:4D is a possible predictive marker of alcohol dependence.

Testosterone Modulates Altered Prefrontal Control of Emotional Actions in Psychopathic Offenders(1,2,3)

Psychopathic individuals are notorious for their controlled goal-directed aggressive behavior. Yet, during social challenges, they often show uncontrolled emotional behavior. Healthy individuals can control their social emotional behavior through anterior prefrontal cortex (aPFC) downregulation of neural activity in the amygdala, with testosterone modulating aPFC-amygdala coupling. This study tests whether individual differences in this neuroendocrine system relate to the paradoxical lack of emotional control observed in human psychopathic offenders. Emotional control was operationalized with an fMRI-adapted approach-avoidance task requiring rule-driven control over rapid emotional responses. Fifteen psychopathic offenders and 19 matched healthy control subjects made approaching and avoiding movements in response to emotional faces. Control of social emotional behavior was required during affect-incongruent trials, when participants had to override affect-congruent, automatic action tendencies and select the opposite response. Psychopathic offenders showed less control-related aPFC activity and aPFC-amygdala coupling during trials requiring control of emotional actions, when compared with healthy control subjects. This pattern was particularly pronounced in psychopathic individuals with high endogenous testosterone levels. These findings suggest that reduced prefrontal coordination underlies reduced behavioral control in psychopathic offenders during emotionally provoking situations. Even though the modest sample size warrants replication, the modulatory role of endogenous testosterone on the aPFC-amygdala circuit suggests a neurobiological substrate of individual differences that is relevant for the advancement of treatment and the reduction of recidivism.

Congenital Adrenal Hyperplasia, Polycystic Ovary Syndrome and criminal behavior: A Swedish population based study

Both prenatal and circulating testosterone and other androgens have been suggested to influence the individual's propensity to commit crime, but empirical evidence is limited and inconsistent. Congenital Adrenal Hyperplasia (CAH) and Polycystic Ovary Syndrome (PCOS) are both hyperandrogenic conditions but with an important difference; whereas subjects with CAH are exposed to high concentrations of androgens in utero, women with PCOS are subjected to high androgens in adulthood. Comparing these groups can therefore yield important insights of androgenic effects on behavior. In the current study, information on medical diagnoses and convicted crimes were gathered from Swedish population-based registers. The associations between diagnoses of CAH or PCOS and any crime, violent crime or sex crime were estimated with conditional logistic regression. Results showed that CAH in women and men did not predict criminality, whereas an increased risk for any crime and violent crime was found in PCOS women. Our findings indicate that female hyperandrogenism in adulthood, but not prenatal hyperandrogenism, is associated with risk for criminal behavior. Further research into hyperandrogenic conditions holds opportunities to deepen our understanding of the etiology of crime and psychopathology.

Correlation Between Personality Traits and Testosterone Concentrations in Healthy Population

OBJECTIVE

High plasma testosterone levels have been associated with aggression, sexual behaviour and social status. The aim of this paper was to study the correlation between basal plasma testosterone levels and personality variables in healthy participants.

MATERIALS AND METHODS

Fifty-four participants were randomly enrolled into this study. Basal plasma testosterone levels were measured between 8:30 am and 10 am. After 24 hours of blood drawing, each subject completed personality questionnaires.

RESULTS

Positive correlation between basal plasma testosterone levels and anti-social personality traits in both genders was observed (r = 0.336 and P < 0.018). Also, a positive correlation was observed between basal plasmatestosterone levels and criminal thinking traits (r = 0. 376, P < 0.05) and Millon compulsive (r = 0.386, P < 0.010) in both genders. In female participants, a positive correlation between basal plasmatestosterone levels and psychoticism (r = 0. 25, P < 0.019) and Cloninger AUTO TCI (r = 0.507, P < 0.004) was observed. In males participants positive correlation between baseline plasmatic Testosterone levels and Millon Antisocial trait (r = 0. 544, P < 0.19) and Millon Hypomania trait (r = 0. 485, P < 0.41) and Millon Drug Abuse trait (r = 0.632, P < 0.05) was reported.

CONCLUSION

Our results suggest gender differences in clinical and personality variables related with basal plasma testosterone level. In men, high plasma testosterone levels were associated with clinical traits, substance abuse and hypomania. Women with higher basal testosterone levels showed higher scores on personality self-direction traits.

Sex differences in the association between testosterone and violent behaviors

Background:

Research on the association between testosterone and violent behavior has provided conflicting findings. The majority of studies on the association between testosterone and antisocial-violent behaviors has used a clinical sample of severely violent individuals. These studies have mostly assessed males.

Objectives:

To study sex differences in the association between testosterone and violent behaviors in a community sample of young adults in the United States.

Patients and Methods:

A longitudinal study of an inner city population on subjects aged from adolescence to adulthood was undertaken. Testosterone and violent behaviors were measured among 257 young adults with an average age of 22 years (range 21 to 23 years). We used regression analysis to test the association between testosterone and violent behaviors in male and female samples.

Results:

There was a significant positive correlation between testosterone levels and violent behaviors among females, but not males. The association between testosterone levels and violent behaviors among females was significant, as it was above and beyond the effects of socio-economic status, age, education, and race.

Conclusions:

Our findings provide more information about the biological mechanisms for violent behaviors among young female adults. The study also helps us better understand sex differences in factors associated with violent behaviors in the community.

A preliminary case study of androgen receptor gene polymorphism association with impulsivity in women with alcoholism

Objective

The androgen receptor (AR) gene, located on the X chromosome, contains a common polymorphism involving cytosine–adenine–guanine (CAG) repeats, which impacts disease and could contribute to the unequal sex ratio in alcoholism. CAG repeats in the AR gene are known to correlate with impulsivity in males. We report the first preliminary study examining the association between the number of CAG repeats and measures of impulsivity in females with chronic alcoholism.

Methods

A total of 35 women and 85 men with chronic alcoholism were previously recruited for a nutritional clinical trial, and 26 well-characterized females (19 African–American and seven Caucasian) with alcoholism agreed to participate for genetic testing. Genomic deoxyribonucleic acid (DNA) was isolated from peripheral blood and CAG repeats determined by analyzing polymerase chain reaction (PCR)-amplified products, using the polymorphic AR gene assay. CAG repeat length was correlated with raw scores from the Barratt Impulsivity Scale, version 11 and the Alcoholism Severity Scale.

Results

CAG repeat lengths were significantly longer in Caucasian alcoholic women compared with African–Americans, and the average number of CAG repeats were significantly, positively correlated (P<0.05) with impulsivity scores. Women with average CAG repeat length (CAG_ave) ≥18, representing the upper quartile of the repeat range, showed significantly greater mean raw impulsivity scores. CAG repeat length appeared to have less effect in African–American compared with Caucasian women, possibly due to a shorter average repeat length.

Conclusion

We found an association between the number of CAG repeats and impulsivity in females with chronic alcoholism, specifically in women with CAG_ave ≥18, seen more commonly in Caucasian compared with African–American women.

The cognitive and neural correlates of psychopathy and especially callous–unemotional traits in youths: A systematic review of the evidence

It is unclear whether the concepts and findings of the underlying neurobiology of adult psychopathy apply to youths as well. If so, a life span approach to treatment should be taken. Because youths’ brains are still developing, interventions at an early age may be far more effective in the long run. The aim of this systematic review is to examine whether the neurocognitive and neurobiological factors that underlie juvenile psychopathy, and specifically callous–unemotional (CU) traits, are similar to those underlying adult psychopathy. The results show that youths with CU traits show lower levels of prosocial reasoning, lower emotional responsivity, and decreased harm avoidance. Brain imaging studies in youths with CU traits are still rare. Available studies suggest specific neural correlates, such as a reduced response of the amygdala and a weaker functional connectivity between the amygdala and the ventromedial prefrontal cortex. These findings are largely in line with existing theories of adult psychopathy, such as the dual-hormone serotonergic hypothesis and the integrated emotions systems theory. We recommend that future studies investigate the role of oxytocin, invest in the study of neural mechanisms, and study the precursors, risk factors, and correlates of CU traits in early infancy and in longitudinal designs.

Psychopathy's influence on the coupling between hypothalamic-pituitary-adrenal and -gonadal axes among incarcerated adolescents

Conduct disorder (CD) is a heterogeneous diagnosis, leading researchers to initiate studies focused on neurobiological mechanisms underlying this disorder. One specifier of CD currently considered for inclusion in the DSM-V is callous-unemotional (CU) traits, a key component of psychopathy. CU traits are thought to have neuroendocrine underpinnings, yet little is known about hypothalamic-pituitary-adrenal (HPA) and -gonadal (HPG) hormones in the context of psychopathic traits. The current study sought to identify daily coupling patterns between HPA and HPG hormones in order to clarify distinct neurobiological underpinning associated with psychopathic/CU traits. Fifty incarcerated adolescent males who met criteria for CD were recruited and provided 10 saliva samples across 2 days. Participants completed the Psychopathy Checklist Youth Version (PCL:YV) and Inventory of Callous Unemotional Traits (ICU) on a third day. Diurnal cortisol, testosterone, and DHEA functioning was modeled via hierarchical linear modeling. Psychopathy subscales from the measures administered were used as predictors of daily coupling patterns between these hormones. Results indicated all three hormones were tightly coupled. Further, higher PCL-YV interpersonal scores related to greater coupling between all three hormones, whereas higher ICU callousness scores related to greater uncoupling of testosterone with cortisol and DHEA. The current study is novel in its emphasis on testing the coupling of HPA and HPG hormones among incarcerated adolescent males. Results suggest that affective and interpersonal psychopathic traits are marked by unique HPA- and HPG coupling.

Psychopaths lack the automatic avoidance of social threat: relation to instrumental aggression

Psychopathy (PP) is associated with marked abnormalities in social emotional behaviour, such as high instrumental aggression (IA). A crucial but largely ignored question is whether automatic social approach-avoidance tendencies may underlie this condition. We tested whether offenders with PP show lack of automatic avoidance tendencies, usually activated when (healthy) individuals are confronted with social threat stimuli (angry faces). We applied a computerized approach-avoidance task (AAT), where participants pushed or pulled pictures of emotional faces using a joystick, upon which the faces decreased or increased in size, respectively. Furthermore, participants completed an emotion recognition task which was used to control for differences in recognition of facial emotions. In contrast to healthy controls (HC), PP patients showed total absence of avoidance tendencies towards angry faces. Interestingly, those responses were related to levels of instrumental aggression and the (in)ability to experience personal distress (PD). These findings suggest that social performance in psychopaths is disturbed on a basic level of automatic action tendencies. The lack of implicit threat avoidance tendencies may underlie their aggressive behaviour.

A review on the relationship between testosterone and life-course persistent antisocial behavior

Life-course persistent antisocial behavior is 10 to 14 times more prevalent in males and it has been suggested that testosterone levels could account for this gender bias. Preliminary studies with measures of fetal testosterone find inconsistent associations with antisocial behavior, especially studies that use the 2D:4D ratio as a proxy for fetal testosterone. However, circulating testosterone consistently shows positive associations with antisocial behaviors throughout childhood, adolescence, and adulthood, particularly in males. It is suggested that high fetal/circulating testosterone interactively influence the maturation and functionality of mesolimbic dopaminergic circuitry, right orbitofrontal cortex, and cortico-subcortical connectivity, resulting in a strong reward motivation, low social sensitivity, and dampened regulation of strong motivational/emotional processes. The link between these testosterone induced endophenotypes and actual display of antisocial behavior is strongly modulated by different social (e.g., social rejection, low SES) and genetic (e.g., MAOA, 5HTT) risk factors that can disturb socio-, psycho-, and biological development and interact with testosterone in shaping behavior. When these additional risk factors are present, the testosterone induced endophenotypes may increase the risk for a chronic antisocial lifestyle. However, behavioral endophenotypes induced by testosterone can also predispose towards socially adaptive traits such as a strong achievement motivation, leadership, fair bargaining behaviors, and social assertiveness. These adaptive traits are more likely to emerge when the high testosterone individual has positive social experiences that promote prosocial behaviors such as strong and secure attachments with his caregivers, affiliation with prosocial peers, and sufficient socioeconomic resources. A theoretical model is presented, various hypotheses are examined, and future venues for research are discussed.

Investigating the influence of prenatal androgen exposure and sibling effects on alcohol use and alcohol use disorder in females from opposite-sex twin pairs

BACKGROUND

There are robust sex differences for alcohol phenotypes, with men reporting more drinking and alcohol use disorder (AUD) symptoms than women. However, the sources of these effects are not completely understood. Sex hormones, a substantial biological sex difference, exert neurobehavioral influences and are candidates for influencing sex differences in alcohol phenotypes. This study investigated the effects of prenatal androgens based on the hypothesis of prenatal hormone transfer, which posits that hormones from one twin influence the development of a cotwin.

METHODS

This study compared female twins from opposite-sex (OSF) and same-sex (SSF) pairs to investigate associations between prenatal androgens and alcohol phenotypes. Additional analyses distinguished prenatal and postnatal effects by comparing OSFs and SSFs with a close-in-age older (CAO) brother.

RESULTS

OSFs endorsed more lifetime AUD symptoms than SSFs (d = 0.14). Females with a CAO brother reported greater intoxication frequency (d = 0.35), hangover frequency (d = 0.24), typical drinking quantity (d = 0.33), and max drinks (i.e., the most drinks ever consumed in a 24-hour period; d = 0.29). Controlling for postnatal effects, OSFs still endorsed more lifetime AUD symptoms than SSFs with a CAO brother (d = 0.16).

CONCLUSIONS

Prenatal exposure to a male cotwin was associated with increases in AUD symptoms, above the effect of postnatal exposure to a male sibling. Prenatal exposure to a male cotwin was not associated with increases in other alcohol-related phenotypes, but postnatal exposure to older male siblings produced medium effect sizes for indicators of alcohol consumption. Sex differences in AUDs, but not alcohol use, may be partially due to the neurodevelopmental effects of prenatal androgens. However, sibling effects may be larger than any effect of prenatal androgen exposure.

The dominance behavioral system and psychopathology: evidence from self-report, observational, and biological studies

The dominance behavioral system (DBS) can be conceptualized as a biologically based system that guides dominance motivation, dominant and subordinate behavior, and responsivity to perceptions of power and subordination. A growing body of research suggests that problems with the DBS are evident across a broad range of psychopathologies. We begin by describing psychological, social, and biological correlates of the DBS. Extensive research suggests that externalizing disorders, mania proneness, and narcissistic traits are related to heightened dominance motivation and behaviors. Mania and narcissistic traits also appear related to inflated self-perceptions of power. Anxiety and depression are related to subordination and submissiveness, as well as a desire to avoid subordination. Models of the DBS have received support from research with humans and animals; from self-report, observational, and biological methods; and use of naturalistic and experimental paradigms. Limitations of available research include the relative lack of longitudinal studies using multiple measures of the DBS and the absence of relevant studies using diagnosed samples to study narcissistic personality disorder and bipolar disorder. We provide suggestions for future research on the DBS and psychopathology, including investigations of the potential usefulness of DBS in differentiating specific disorder outcomes, the need for more sophisticated biological research, and the value of longitudinal dynamical research. Implications of using the DBS as a tool in clinical assessment and treatment are discussed.

The Antihero in Popular Culture: Life History Theory and the Dark Triad Personality Traits

The Dark Triad of personality is composed of narcissism, psychopathy, and Machiavellianism. Despite the common belief that these traits are undesirable, the media is awash with characters that embody the Dark Triad. Characters like Gregory House, M.D., Batman (a.k.a. the Dark Knight), and James Bond all embody these traits and are some of the most popular media franchises today. As entertaining as these characters are, they provide us with a window into the dark side of human nature. Instead of treating the dark side of human nature as inherently maladaptive, we provide an alternative view that, despite their costs, traits like these can confer reproductive and survival benefits for the individual. In so doing, we review the research on the Dark Triad traits and provide a theoretical account for how these traits can confer some positive benefits. To facilitate comprehension, we provide examples taken from the media to show how evolutionary psychology and popular culture intersect.

A review on the relationship between testosterone and the interpersonal/affective facet of psychopathy

Testosterone (T) has received increasing interest in the recent years as a probable biological determinant in the etiology of male-biased clinical conditions such as psychopathy (i.e. psychopathy is more prevalent in men and leads to an earlier onset and more severe expression of antisocial and aggressive behavior in men compared to women). In this review, the authors evaluated the potential relationship between T and different constructs closely related to the core characteristics of psychopathy (affective empathy, fear-reactivity, and instrumental aggression). After a thorough examination of the literature, it is concluded that high T exposure in utero and high circulating T levels throughout important life phases (most notably adolescence) or in response to social challenges (e.g. social stress, competition) could be an important etiological risk factor in the emergence of psychopathic behavior. Nevertheless, studies consistently indicate that high T is not related to a significantly reduced fear-reactivity and is only indirectly associated with the increased levels of instrumental aggression observed in psychopathic individuals. Therefore, psychopathy is likely to arise from an interaction between high T levels and other biological and socio-psychological risk factors, such as a constitutionally based dampened fear-reactivity, insecure/disordered attachment processes in childhood, and social discrimination/rejection in adolescence and/or adulthood.

Neurosteroid influences on sensitivity to ethanol

This review will highlight a variety of mechanisms by which neurosteroids affect sensitivity to ethanol, including physiological states associated with activity of the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes, and the effects of chronic exposure to ethanol, in addition to behavioral implications. To date, γ-aminobutyric acid (GABA(A)) receptor mechanisms are a major focus of the modulation of ethanol effects by neuroactive steroids. While NMDA receptor mechanisms are gaining prominence in the literature, these complex data would be best discussed separately. Accordingly, GABA(A) receptor mechanisms are emphasized in this review with brief mention of some NMDA receptor mechanisms to point out contrasting neuroactive steroid pharmacology. Overall, the data suggest that neurosteroids are virtually ubiquitous modulators of inhibitory neurotransmission. Neurosteroids appear to affect sensitivity to ethanol in specific brain regions and, consequently, specific behavioral tests, possibly related to the efficacy and potency of ethanol to potentiate the release of GABA and increase neurosteroid concentrations. Although direct interaction of ethanol and neuroactive steroids at common receptor binding sites has been suggested in some studies, this proposition is still controversial. It is currently difficult to assign a specific mechanism by which neuroactive steroids could modulate the effects of ethanol in particular behavioral tasks.

Increased testosterone-to-cortisol ratio in psychopathy

Only a few studies have examined hormones in psychopathy, and results have been mixed. It has been suggested that because hormone systems are highly interconnected, it may be important to examine multiple systems simultaneously to gain a clearer picture of how hormones work together to predispose for a certain construct. In the present study, we attempt to clarify the role of the hormones cortisol and testosterone in psychopathy by examining both hormones in a community sample of 178 adults demonstrating a wide range of psychopathy scores. Results showed that psychopathy scores were associated with an increased ratio of testosterone (baseline) to cortisol responsivity to a stressor. Psychopathy was not associated with either of these measures independently or with baseline cortisol levels. These findings suggest that these highly interconnected hormone systems may work in concert to predispose to psychopathy.

Neural mechanisms of the testosterone-aggression relation: the role of orbitofrontal cortex

Testosterone plays a role in aggressive behavior, but the mechanisms remain unclear. The present study tested the hypothesis that testosterone influences aggression through the OFC, a region implicated in self-regulation and impulse control. In a decision-making paradigm in which people chose between aggression and monetary reward (the ultimatum game), testosterone was associated with increased aggression following social provocation (rejecting unfair offers). The effect of testosterone on aggression was explained by reduced activity in the medial OFC. The findings suggest that testosterone increases the propensity toward aggression because of reduced activation of the neural circuitry of impulse control and self-regulation.

The neurobiology of psychopathy: a neurodevelopmental perspective

We provide an overview of the neurobiological underpinnings of psychopathy. Cognitive and affective-emotional processing deficits are associated with abnormal brain structure and function, particularly the amygdala and orbitofrontal cortex. There is limited evidence of lower cortisol levels being associated with psychopathic personality. Initial developmental research is beginning to suggest that these neurobiological processes may have their origins early in life. Findings suggest that psychopathic personality may, in part, have a neurodevelopmental basis. Future longitudinal studies delineating neurobiological correlates of the analogues of interpersonal-affective and antisocial features of psychopathy in children are needed to further substantiate a neurodevelopmental hypothesis of psychopathy.

The neurobiology of psychopathy

Numerous studies have tackled the complex challenge of understanding the neural substrates of psychopathy, revealing that brain abnormalities exist on several levels and in several structures. As we discover more about complex neural networks, it becomes increasingly difficult to clarify how these systems interact with each other to produce the distinct pattern of behavioral and personality characteristics observed in psychopathy. The authors review the recent research on the neurobiology of psychopathy, beginning with molecular neuroscience work and progressing to the level of brain structures and their connectivity. Potential factors that may affect the development of brain impairments, as well as how some systems may be targeted for potential treatment, are discussed.

An orbitofrontostriatopallidal pathway for morality: evidence from postlesion antisocial and obsessive-compulsive disorder

INTRODUCTION

A detailed proposal is made to the effect that nonlesional antisocial personality disorder (APD) is, among other things, a dysfunctional hypomoralism and that nonlesional obsessive-compulsive disorder (OCD) is, among other things, a dysfunctional hypermoralism.

METHOD

To provide an empirical test of this proposal, 25 previously published cases of acquired (post lesion) APD and 39 cases of acquired OCD are reviewed and compared with multivariate inference tests.

RESULTS

The acquired APD patients most often present putamenal or pallidal lesions.

CONCLUSION

The ensemble of neurobiological, endocrine, and behavioural traits in APD and OCD, as well as the distinct lesion sites in the acquired variants, support the notion of an orbitofrontostriatopallidal brain system underlying morality.

Exogenous testosterone enhances responsiveness to social threat in the neural circuitry of social aggression in humans

BACKGROUND

In a range of species, the androgen steroid testosterone is known to potentiate neural circuits involved in intraspecific aggression. Disorders of impulsive aggression in humans have likewise been associated with high testosterone levels, but human evidence for the link between testosterone and aggression remains correlational and inconclusive.

METHODS

Twelve female participants underwent functional magnetic resonance imaging during three sessions while viewing stimuli differing in social threat value: angry and happy facial expressions. The first session served to establish associations between baseline hormone levels and neural activation. Participants were retested in a second and third session after placebo-controlled sublingual administration of .5 mg testosterone.

RESULTS

Findings demonstrate consistent activation to angry versus happy faces in areas known to be involved in vertebrate reactive aggression, such as the amygdala and hypothalamus. Suprathreshold clusters were also found in the orbitofrontal cortex (Brodmann area 47), a region implicated in impulse control in humans. Baseline endocrine profiles of high testosterone and low cortisol were associated with stronger activation in subcortical structures. Neural responses in most activated regions were more persistent after testosterone administration than after placebo.

CONCLUSIONS

These data demonstrate that testosterone enhances responsiveness in neural circuits of social aggression. Based on animal literature, it is argued that actions of testosterone on subcortical reactive aggression circuits give rise to this effect. Implications for our understanding of the pathophysiology of disorders of impulsive aggression are discussed.

Sex, aggression and impulse control: an integrative account

There is evidence that the male sex and a personality style characterized by low self-control/high impulsivity and a propensity for negative emotionality increase the risk for impulsive aggressive, antisocial and criminal behavior. This article aims at identifying neurobiological factors underlying this association. It is concluded that the neurobiological correlates of impulsive aggression act through their effects on the ability to modulate impulsive expression more generally, and that sex-related differences in the neurobiological correlates of impulse control and emotion regulation mediate sex differences in direct aggression. A model is proposed that relates impulse control and its neurobiological correlates to sex differences in direct aggression.

Exogenous testosterone attenuates the integrated central stress response in healthy young women

Animal research has shown that the androgen steroid testosterone, the end product of the hypothalamic-pituitary-gonadal (HPG) axis, down regulates the integrated stress response at multiple levels. These effects have been demonstrated at the level of the amygdala and the bed nucleus of the stria terminalis, and along the different nodes of the hypothalamic-pituitary-adrenal (HPA) axis. The present study was designed to assess effects of exogenous testosterone upon reactivity of the autonomic nervous system and modulation of the acoustic startle reflex in humans. Twenty healthy female participants received double-blind, placebo-controlled sublingual administrations of .5mg testosterone. Measurements were made of phasic electrodermal activity, cardiac responses, and startle reflexes to acoustic probes while participants were exposed to pictures with strongly aversive, neutral, or positive content. Subjective reports of mood and picture evaluations were also obtained. Results support the hypothesis of a generally decreased responsiveness of the stress system by showing reduced skin conductance responses as well as reduced affective startle modulation in anxiety-prone participants after administration of testosterone. Candidate neurobiological mechanisms of action are outlined and discussed, and it is argued that androgens promote dynamic regulation of the stress system through actions upon central neuropeptidergic pathways that control corticotropin releasing hormone (CRH) and arginine vasopressin (AVP) expression. The present findings highlight the importance of further investigation of the possible role of the HPG axis in disorders that are associated with HPA axis dysfunctions.

Role of sex hormone-binding globulin in the relationship between sex hormones and antisocial and aggressive personality in inmates

Plasma total testosterone (TT), free bioavailable testosterone (BT), sex hormone-binding globulin (SHGB), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were analysed in a sample of 89 inmates. Also, the tendency towards an Antisocial Personality Disorder (AAPS) and Aggressiveness (based on an index containing three scales of the Buss-Durkee Hostility Inventory; BDHI) was assessed. Results showed strong correlations between SHBG, total testosterone and free bioavailable testosterone. SHBG and total testosterone correlated with Aggressiveness (0.39 and 0.29, respectively), though the latter turned out not to be significant when SHBG level was controlled. The group with a high probability of Antisocial Personality Disorder and the group with high scores in Aggressiveness obtained higher SHBG levels. Recidivists and subjects already sentenced presented higher concentrations of SHBG. No significant relation was found for the free bioavailable testosterone. It is argued that the relationship between testosterone and antisocial personality and aggressiveness is mediated by the role of SHBG. We conclude that subjects with a disinhibited life-style tend to abuse intoxicants affecting the production of SHBG in the liver. This effect is observed in healthy subjects and delinquents, but more strongly in the population of delinquents.

Testosterone administration reduces empathetic behavior: a facial mimicry study

Although high baseline testosterone levels correlate with low empathy, there is no causal evidence for this association in humans. The present study tested the causality of this relationship by manipulating testosterone levels in a double-blind placebo controlled crossover design. 20 healthy female participants received either a sublingual administration of a single dose of testosterone or placebo on 2 days and were tested 4 h after administration. Because research has shown that facial expression mimicry is a non-obtrusive index of empathy, facial electromyography was measured in response to dynamic facial expressions of happy and angry faces. Results showed that testosterone generally decreased facial mimicry. These findings are consistent with models that assign a critical role to mimicry in the ability to develop and communicate empathy towards conspecifics, and provide a potential causal mechanism of effects of testosterone on empathy.

Unmasking feigned sanity: a neurobiological model of emotion processing in primary psychopathy

INTRODUCTION

The neurobiological basis of primary psychopathy, an emotional disorder characterised by a lack of fear and empathy, on the one hand, and extremely violent, antisocial tendencies, on the other, is relatively unknown. Nevertheless, theoretical models that emphasise the role of fearlessness, imbalanced motivation, defective somatic markers, and dysfunctional violence inhibition mechanisms have complementary proposals regarding motivations and brain mechanisms involved.

METHODS

Presently, incorporating the heuristic value of these models and further theorising on the basis of recent data from neuropsychology, neuroendocrinology, neuroimaging, and repetitive transcranial magnetic stimulation (rTMS), an attempt is made to construct a neurobiological framework of emotion processing in primary psychopathy with clinical applicability.

RESULTS

According to this framework, defective emotional processing in primary psychopathy results from bottom-up hormone-mediated imbalances at: (1) the subcortical level; (2) in subcortico-cortical "cross-talk"; that end up in an instrumental stance at the cortical level (3). An endocrine dual-system approach for the fine-tuned restoration of these hormone-mediated imbalances is proposed as a possible clinical application.

DISCUSSION

This application may be capable of laying a neurobiological foundation for more successful sociotherapeutic interventions in primary psychopathy.

Sensation seeking, sexual curiosity and testosterone in inmates

The relationships between sensation seeking, curiosity about sex, and total and free testosterone in inmates were investigated. The role of other hormones such as luteinizing hormone (LH), follicle-stimulating hormone (FSH), and sex hormone-binding globulin (SHBG) in these relationships was also analyzed. Previous analysis allowed the deletion of extreme hormone values affecting the distribution of the variables. In spite of obtaining a high mean for SHBG, relationships between hormones were appropriate. It was observed that higher values of SHBG produce an increment in total testosterone, but not in free testosterone. Positive relationships between total testosterone and the Disinhibition scale of the Sensation Seeking Scale Form V were replicated, although they were affected by SHBG. Significant relationships between total and free testosterone and curiosity about sex were also found. LH and FSH did not influence these patterns of relations. It was suggested that relationships between SHBG and sensation seeking in inmates could be mediated by items referring to alcohol and drugs. The high levels of SHBG observed in the sample reinforced this suggestion. In spite of the role of SHBG, subjects who were desinhibited and concerned about sex presented higher concentrations of total and free testosterone. The results support Zuckerman's sensation seeking theory.

The childhood-onset neuropsychiatric background to adulthood psychopathic traits and personality disorders

Childhood conduct disorder (CD) and adult psychopathic traits according to the Psychopathy Checklist Revised (PCL-R) were the closest psychiatric covariates to repeated violent crimes and aggression among offenders under forensic psychiatric investigation in Sweden. As psychopathy is not included in the present psychiatric diagnostic systems, we compared total and factor PCL-R scores to Axis I disorders, including childhood-onset neuropsychiatric disorders, and to Axis II personality disorders, to establish the convergence of psychopathic traits with other psychiatric diagnoses, and to identify possible unique features. Psychopathic traits were positively correlated with bipolar mood disorder and negatively with unipolar depression. The total PCL-R scores as well as the Factor 2 (unemotionality) and Factor 3 (behavioral dyscontrol) scores were significantly correlated with attention-deficit/hyperactivity disorder, Asperger's syndrome/high-functioning autistic traits, CD, substance abuse, and the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Cluster B personality disorders. The interpersonal Factor 1 showed none of these correlations and may capture features that are specific to psychopathy, distinguishing core psychopathy from other diagnostic definitions.

Testosterone shifts the balance between sensitivity for punishment and reward in healthy young women

Animal research has demonstrated reductions in punishment sensitivity and enhanced reward dependency after testosterone administration. In humans, elevated levels of testosterone have been associated with violent and antisocial behavior. Interestingly, extreme forms of violent and antisocial behavior can be observed in the psychopath. Moreover, it has been argued that reduced punishment sensitivity and heightened reward dependency are crucially involved in the etiology and maintenance of psychopathy. A task that has been proven to be capable of simulating punishment-reward contingencies is the IOWA gambling task. Decisions to choose from decks of cards become motivated by punishment and reward schedules inherent in the task. Importantly, clinical and subclinical psychopaths demonstrate a risky, disadvantageous pattern of decision-making in the task, indicating motivational imbalance (insensitivity for punishment and enhanced reward dependency). Here, in a double-blind placebo-controlled crossover design (n = 12), whether a single administration of testosterone would shift the motivational balance between the sensitivity for punishment and reward towards this tendency to choose disadvantageously was investigated. As hypothesized, subjects showed a more disadvantageous pattern of decision-making after testosterone compared to placebo administration. These findings not only provide the first direct evidence for the effects of testosterone on punishment-reward contingencies in humans, but they also give further insights into the hypothetical link between testosterone and psychopathy.