Off
The Human Amygdala and the Induction and Experience of Fear
Justin Feinstein, Ralph Adolphs, Antonio Damasio, Daniel Tranel
Current Biology, forthcoming
Abstract:
Although clinical observations suggest that humans with amygdala damage have abnormal fear reactions and a reduced experience of fear, these impressions have not been systematically investigated. To address this gap, we conducted a new study in a rare human patient, SM, who has focal bilateral amygdala lesions. To provoke fear in SM, we exposed her to live snakes and spiders, took her on a tour of a haunted house, and showed her emotionally evocative films. On no occasion did SM exhibit fear, and she never endorsed feeling more than minimal levels of fear. Likewise, across a large battery of self-report questionnaires, 3 months of real-life experience sampling, and a life history replete with traumatic events, SM repeatedly demonstrated an absence of overt fear manifestations and an overall impoverished experience of fear. Despite her lack of fear, SM is able to exhibit other basic emotions and experience the respective feelings. The findings support the conclusion that the human amygdala plays a pivotal role in triggering a state of fear and that the absence of such a state precludes the experience of fear itself.
-----------------------
Intergenerational transmission of relationship aggression: A prospective longitudinal study
Ming Cui et al.
Journal of Family Psychology, December 2010, Pages 688-697
Abstract:
The present study examined whether physical and verbal aggression in the family of origin were associated with similar patterns of aggression in young adult couples. Hypotheses were tested using a sample of 213 focal individuals who were followed from adolescence to adulthood. Results suggested that aggression in the family when focal participants were adolescents predicted aggression with romantic partners when participants were adults. The association between interparental aggression and later aggression in adult romantic unions was partially mediated through parents' aggression to focal participants when they were adolescents. Both physical and verbal aggression revealed the same pattern of findings. All together, these findings are consistent with a developmental-interactional perspective (Capaldi & Gorman-Smith, 2003) concerning the developmental origins of aggression in intimate relationships.
-----------------------
Molly Crockett et al.
Emotion, December 2010, Pages 855-862
Abstract:
Human cooperation may partly depend on the presence of individuals willing to incur personal costs to punish noncooperators. The psychological factors that motivate such 'altruistic punishment' are not fully understood; some have argued that altruistic punishment is a deliberate act of norm enforcement that requires self-control, while others claim that it is an impulsive act driven primarily by emotion. In the current study, we addressed this question by examining the relationship between impulsive choice and altruistic punishment in the ultimatum game. As the neurotransmitter serotonin has been implicated in both impulsive choice and altruistic punishment, we investigated the effects of manipulating serotonin on both measures. Across individuals, impulsive choice and altruistic punishment were correlated and increased following serotonin depletion. These findings imply that altruistic punishment reflects the absence rather than the presence of self control, and suggest that impulsive choice and altruistic punishment share common neural mechanisms.
-----------------------
Psychological essentialism and its association with stigmatization
Andrew Howell, Brittany Weikum & Heather Dyck
Personality and Individual Differences, January 2011, Pages 95-100
Abstract:
The present research examined the relationship between individual differences in essentialist beliefs and stigmatizing attitudes. In three cross-sectional studies, undergraduate students (Ns = 171, 197, and 200) completed measures of essentialism and stigmatizing attitudes towards people with either mental disorder or substance abuse. Results consistently showed that those who endorsed essentialist beliefs harboured more stigmatizing attitudes. Results are considered in terms of stigma reduction approaches.
-----------------------
Violent video games prime both aggressive and positive cognitions
Wolfgang Bösche
Journal of Media Psychology, Winter 2010, Pages 139-146
Abstract:
Previous studies have shown that violent video games prime aggressive thoughts and concepts. Interestingly, positively valenced test stimuli are rarely used in this field, though they might provide useful information on the nature of the emotional response to virtual violence and its associative structure. According to the General Aggression Model (GAM) and its extensions (Carnagey, Anderson, & Bushman, 2007), normal negative reactions to violence are expected. Alternatively, playing violent video games might be construed as engaging in positively valenced playful fighting behavior. To test the potential of violent video games to prime positive concepts, N = 29 adult males played either a violent or a nonviolent video game for 20 minutes and were subsequently tested in a standard lexical decision task consisting of positive, aggressive, nonaggressive negative, and neutral target words. The data show that the violent video game primed aggressive concepts as expected, but also raised positive concepts, and did so independently of the participants' history of playing violent video games. Therefore, the results challenge the idea that violent video games inherently stimulate negative concepts only.
-----------------------
Barbara Krahé et al.
Journal of Personality and Social Psychology, forthcoming
Abstract:
This study examined the links between desensitization to violent media stimuli and habitual media violence exposure as a predictor and aggressive cognitions and behavior as outcome variables. Two weeks after completing measures of habitual media violence exposure, trait aggression, trait arousability, and normative beliefs about aggression, undergraduates (N = 303) saw a violent film clip and a sad or a funny comparison clip. Skin conductance level (SCL) was measured continuously, and ratings of anxious and pleasant arousal were obtained after each clip. Following the clips, participants completed a lexical decision task to measure accessibility of aggressive cognitions and a competitive reaction time task to measure aggressive behavior. Habitual media violence exposure correlated negatively with SCL during violent clips and positively with pleasant arousal, response times for aggressive words, and trait aggression, but it was unrelated to anxious arousal and aggressive responding during the reaction time task. In path analyses controlling for trait aggression, normative beliefs, and trait arousability, habitual media violence exposure predicted faster accessibility of aggressive cognitions, partly mediated by higher pleasant arousal. Unprovoked aggression during the reaction time task was predicted by lower anxious arousal. Neither habitual media violence usage nor anxious or pleasant arousal predicted provoked aggression during the laboratory task, and SCL was unrelated to aggressive cognitions and behavior. No relations were found between habitual media violence viewing and arousal in response to the sad and funny film clips, and arousal in response to the sad and funny clips did not predict aggressive cognitions or aggressive behavior on the laboratory task. This suggests that the observed desensitization effects are specific to violent content.
-----------------------
Douglas Gentile, Sarah Coyne & David Walsh
Aggressive Behavior, forthcoming
Abstract:
Many studies have shown that media violence has an effect on children's subsequent aggression. This study expands upon previous research in three directions: (1) by examining several subtypes of aggression (verbal, relational, and physical), (2) by measuring media violence exposure (MVE) across three types of media, and (3) by measuring MVE and aggressive/prosocial behaviors at two points in time during the school year. In this study, 430 3rd-5th grade children, their peers, and their teachers were surveyed. Children's consumption of media violence early in the school year predicted higher verbally aggressive behavior, higher relationally aggressive behavior, higher physically aggressive behavior, and less prosocial behavior later in the school year. Additionally, these effects were mediated by hostile attribution bias. The findings are interpreted within the theoretical framework of the General Aggression Model.
-----------------------
Tracie Afifi et al.
Journal of Psychiatric Research, forthcoming
Background: Although, a large population-based literature exists on the relationship between childhood adversity and Axis I mental disorders, research on the link between childhood adversity and Axis II personality disorders (PDs) relies mainly on clinical samples. The purpose of the current study was to examine the relationship between a range of childhood adversities and PDs in a nationally representative sample while adjusting for Axis I mental disorders.
Methods: Data were from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; n = 34,653; data collection 2004-2005); a nationally representative sample of the United States population aged 20 years and older.
Results: The results indicated that many types of childhood adversity were highly prevalent among individuals with PDs in the general population and childhood adversity was most consistently associated with schizotypal, antisocial, borderline, and narcissistic PDs. The most robust childhood adversity findings were for child abuse and neglect with cluster A and cluster B PDs after adjusting for all other types of childhood adversity, mood disorders, anxiety disorders, substance use disorders, other PD clusters, and sociodemographic variables (Odd Ratios ranging from 1.22 to 1.63). In these models, mood disorders, anxiety disorders, and substance use disorders also remained significantly associated with PD clusters (Odds Ratios ranging from 1.26 to 2.38).
Conclusions: Further research is necessary to understand whether such exposure has a causal role in the association with PDs. In addition to preventing child maltreatment, it is important to determine ways to prevent impairment among those exposed to adversity, as this may reduce the development of PDs.
-----------------------
Increased testosterone-to-cortisol ratio in psychopathy
Andrea Glenn et al.
Journal of Abnormal Psychology, forthcoming
Abstract:
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.
-----------------------
Steven Beach et al.
Psychosomatic Medicine, January 2011, Pages 83-87
Objective: To examine epigenetic processes linking childhood sex abuse to symptoms of antisocial personality disorder (ASPD) in adulthood and to investigate the possibility that the link between childhood sex abuse and deoxyribonucleic acid methylation at the 5HTT promoter might represent a pathway of long-term impact on symptoms of ASPD.
Method: Deoxyribonucleic acid was prepared from lymphoblast cell lines derived from 155 female participants in the latest wave of the Iowa Adoptee Study. Methylation at 71 CpG residues was determined by quantitative mass spectroscopy, and the resulting values were averaged to produce an average CpG ratio for each participant. Simple associations and path analyses within an Mplus framework were examined to characterize the relationships among childhood sex abuse, overall level of methylation among women, and subsequent antisocial behavior in adulthood. Direct effects of biological parent psychopathology and 5HTT genotype were controlled.
Results: Replicating prior work, we found that a significant effect of childhood sex abuse on methylation of the 5HTT promoter region emerged for women. In addition, a significant effect of methylation at 5HTT on symptoms of ASPD emerged.
Conclusions: Child sex abuse may create long-lasting changes in methylation of the promoter region of 5HTT in women. Furthermore, hypermethylation may be one mechanism linking childhood sex abuse to changes in risk for adult antisocial behavior in women. Better understanding of the methylome may prove critical in understanding the role of childhood environments on long-term psychiatric sequelae.
-----------------------
Personality disorders and cigarette smoking among adults in the United States
Michael Zvolensky, Elizabeth Jenkins, Kirsten Johnson & Renee Goodwin
Journal of Psychiatric Research, forthcoming
Introduction: There is a paucity of empirical information pertaining to the association between personality disorders and cigarette smoking. The present study examined whether, and to what degree, personality disorders are associated with cigarette smoking; investigated the specificity of any observed smoking-personality disorder association; and the role of mood/anxiety disorders, substance use, and nicotine dependence in those relations.
Methods: Data were drawn from the National Epidemiologic Survey of Alcohol and Related Conditions (NESARC), a nationally representative sample of 43,083 adults in the United States.
Results: Results indicated a substantial percentage of those with personality disorders are nicotine dependent. Interestingly, the association between dependent, avoidant, histrionic, schizoid and paranoid personality disorders as well as former dependent smoking was partially explained by co-occurring mood/anxiety disorders, and adjusting for such clinical conditions appeared to generally attenuate the strength of many other associations. Finally, the association between personality disorders and smoking appears to differ by specific personality disorder, with some of the strongest relations being evident for antisocial personality disorder.
Discussion: These novel empirical findings are discussed in relation to the relevance of cigarette smoking among those with personality disorders.
-----------------------
Cell phone use and behavioural problems in young children
Hozefa Divan, Leeka Kheifets, Carsten Obel & Jørn Olsen
Journal of Epidemiology and Community Health, forthcoming
Background: Potential health effects of cell phone use in children have not been adequately examined. As children are using cell phones at earlier ages, research among this group has been identified as the highest priority by both national and international organisations. The authors previously reported results from the Danish National Birth Cohort (DNBC), which looked at prenatal and postnatal exposure to cell phone use and behavioural problems at age 7 years. Exposure to cell phones prenatally, and to a lesser degree postnatally, was associated with more behavioural difficulties. The original analysis included nearly 13 000 children who reached age 7 years by November 2006.
Methods: To see if a larger, separate group of DNBC children would produce similar results after considering additional confounders, children of mothers who might better represent current users of cell phones were analysed. This ‘new' dataset consisted of 28 745 children with completed Age-7 Questionnaires to December 2008.
Results: The highest OR for behavioural problems were for children who had both prenatal and postnatal exposure to cell phones compared with children not exposed during either time period. The adjusted effect estimate was 1.5 (95% CI 1.4 to 1.7).
Conclusions: The findings of the previous publication were replicated in this separate group of participants demonstrating that cell phone use was associated with behavioural problems at age 7 years in children, and this association was not limited to early users of the technology. Although weaker in the new dataset, even with further control for an extended set of potential confounders, the associations remained.
-----------------------
Michael Dahl, Jimmi Nielsen & Ramin Mojtabai
Scandinavian Journal of Public Health, December 2010, Pages 857-863
Aims: Entering entrepreneurship (i.e. becoming an entrepreneur) is known to be a demanding activity with increased workload, financial uncertainty and increased levels of stress. However, there are no systematic studies on how entering entrepreneurship affects the people involved.
Methods: The authors investigated prescriptions of psychotropics for 6,221 first-time entrepreneurs from 2001-2004 and their 2,381 spouses in the first two years after becoming entrepreneurs in a matched case-control study using linked data from three Danish national registries: The Danish database for Labor Market Research, the Danish Entrepreneurship database and the Danish Prescription database.
Results: Entrepreneurs were more likely to fill prescriptions at pharmacies for sedatives/hypnotics (adjusted odds ratio (AOR): 1.45 [95% CI: 1.26-1.66], p < .0001). However, they were less likely to fill prescriptions for antidepressants (AOR: 0.74 [95% CI: 0.59-0.92] p = 0.007). Spouses of these entrepreneurs were also more likely to fill prescriptions for sedatives/hypnotics (AOR: 1.36 [95% CI: 1.10-1.67], p = 0.005). No difference in prescription of antidepressants was found for spouses.
Conclusions: This study showed that there was a significant relation between entering entrepreneurship and receiving prescriptions for sedative/ hypnotics both among the entrepreneurs themselves and their spouses, suggesting that entering entrepreneurship may be associated with increased stress for both the entrepreneurs and their families.
-----------------------
Relationships between early behavioural characteristics and temperament at 6 years
Josefa Canals, Carmen Hernández-Martínez & Joan Fernández-Ballart
Infant Behavior and Development, forthcoming
Abstract:
The aim of this study was to analyze the extent to which the relations and the stability of the neonatal behaviour and the infant behaviour at both 4 and 12 months could be used to predict the infant temperament at 6 years. Seventy-two full-term, normal-weight, healthy children were followed from 3 days postpartum to 6 years. Neonatal behaviour at 3 and 30 days was assessed using the Neonatal Behaviour Assessment Scale (NBAS), behaviour at 4 and 12 months was assessed using the Infant Behaviour Record (IBR) from the Bayley Scales for Infant Development (BSID) and temperament at 6 years was assessed using the Dimensions of Temperament Survey-Revised (DOTS-R). Negative and positive affectivity and attention were the factors extracted from the behaviours of the IBR. Our results showed a low/moderate correlation between neonatal behaviour on the one hand and behaviour at 4 and 12 months and temperament at 6 years on the other hand. The motor performance, orientation and ANS stability of the neonate at 3 and 30 days were predictors of positive and negative affectivity at 4 months. State regulation and ANS stability at 3 days were predictors of negative affectivity and attention respectively at 12 months. Negative affectivity at 12 months and endurance at 30 days were predictors of general activity and persistence/attention at 6 years. Also, an inverse relation was found between state regulation at 30 days and general activity at 6 years, and a positive relation was found between attention at 4 months and persistence/attention at 6 years. We conclude that neonatal behaviour and behaviour in the first year of life are good predictors of temperament at 6 years and that early negative affectivity has an important role on infant temperament development.