To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
In their excellent review of the environmental and genetic underpinnings of personality disorders, Turner, Prud’homme, and Legg (this volume) provide compelling evidence that early family adversity (e.g., maltreatment, parenting difficulties, parental separation) is an environmental risk factor for offspring personality difficulties. However, little is known about how and why these family characteristics increase the risk for various personality disorders. Guided by evolutionary theory, the goal of this commentary is to illustrate how the synthesis of these two areas of inquiry may advance an understanding of the origins and course of typical and atypical personality characteristics in mutually informative ways. First, building on the coverage of attachment in the primary chapter, the authors address how other behavioral systems that are designed to defend against social threat and acquire resources may mediate the distinct personality sequelae experienced by children exposed to family adversity. Second, in identifying sources of heterogeneity in family risk, the authors highlight the value of expanding the conceptualization of moderators beyond diathesis-stress models. Consistent with differential susceptibility theory, they describe how temperamental, physiological, and genetic moderators may serve to heighten sensitivity to supportive as well as adverse family conditions rather than simply acting as diatheses that selective sensitize individuals to harsh socialization contexts.
Science explains how marijuana produces the experience of being high after Herkenham mapped location of the densest concentrations of CB1 receptors. The hippocampus, amygdala, and basal ganglia/cerebellum have especially dense cannabinoid receptors and THC impacts the functions produced by these areas in conspicuously noticeable ways. The hippocampus produces short term memory, an important element in learning. Reduced working memory is the most documented cognitive impairment caused by acute marijuana use. The endocannabinoid system is also uniquely responsible for forgetting negative experiences. The amygdala modulates anxiety, appetites, the sense of novelty and the hypothalamus. When THC stimulates the amygdala, most people experience relaxation, hunger (“munchies”) and altered sensory experience due to dishabituation to stimuli. Hypothalamic modulation by the amygdala results in reduction of the stress response, leading to the “chill” of being high. And genetic differences in CB1 density determines aspects of temperament. Supranormal stimulation of CB1 receptors in the basal ganglia reduces spontaneous motor activity and THC stimulation of the cerebellum reduces fine motor control and alters the sense of time and driving skills. The experience of being high is the culmination of altered brain function in the above areas with the highest CB1 density.
Piero’s behaviour in the months before the denouement of the cousins’ conspiracy in late April showed the two contrasting sides of his nature: lazy and hyperactively scheming. Both were pinpointed by Becchi’s idiosyncratic turn of phrase when he criticised him – on one hand – for letting ser Piero Dovizi govern Italy as his boss while he rested on his oars, ‘allowing some wind to blow the boat where the oars can’t arrive, it wears you out to use your arms’, and on the other for restlessly moving in a rocking gondola: ‘keep still, for God’s sake, for you can’t see everything and you shouldn’t help the side opposite to yours’.1 Outwardly, at least, Piero seemed unworried either by his cousins or by the French expedition. He stood high in the pope’s esteem as the broker of a possible marriage for little Laura (the pope’s daughter) and, indeed, as Florence’s St. Peter, ‘the rock on which our city is now rising up’.2 He was also as ‘ambiguous’ as the pope, ‘temporising in order to see whom to please’. After receiving despatches from France, Milan, Rome and Naples in November 1493, with news of ‘Ferrante’s trepidation, the pope’s instability and the general state of affairs in Milan’, Piero told Dovizi he had little to reply except that he was waiting to hear more before writing to Becchi in France, so that, ‘well informed, [Becchi] can … temporise or do as he thinks fit’.3 In the meantime, he was busy organising the joust that he and his friends had long been practising for – probably on the large tract of public land along the walls he had enclosed in November as a jousting yard. In Piazza S. Croce the stockades had been built and the seating was being constructed.4 Then, at the end of January, everything came to an abrupt halt, not because of the cousins or news from France, but because of the death of Ferrante of Naples on 25 January 1494.
Piero’s life has been a missing chapter in the history of Florence during its transition from republic to principate, considered irrelevant, except by its failings, to the crisis of Italian states at this time. As with any biography, the importance of his life lies in providing a witness to events as they happened – in his case the threat to Italy’s, and especially Florence’s, stability in the face of foreign invasions. Piero was very articulate in expressing himself and the pressure he suffered in his unofficial role as Florence’s capo, neither powerful enough to rule nor free enough to indulge his talents and pleasures as a prince. He enables us to appreciate the situation faced by republics like Florence that had become territorial states without the military power or the permanent leadership to withstand foreign armies – except at risk of being accused of tyranny. This, of course, was Piero’s fate, and it again raises the question of whether he was the ambitious tyrant that his reputation suggests or whether, instead, his temperament and experience would have qualified him to be the new type of civilian ruler that political realists like Machiavelli, Francesco Vettori and Guicciardini were proposing for Florence after the unexpected death of Piero’s son in 1519.
Early callous-unemotional (CU) behaviors identify children at risk for severe and persistent aggression and antisocial behavior. Recent work suggests that fearlessness and low social affiliation are implicated in the etiology of CU behaviors, although more research is needed to clarify these etiological pathways, as well as the role of parenting.
Using a sample of preschoolers (N = 620), we examined pathways between observed fear in response to social and non-social stimuli and observed social affiliation during social interactions at age 3 and increases child CU behaviors and oppositional-defiant behaviors from ages 3 to 5. To elucidate the role of parenting in exacerbating or buffering the relationships between low fear and social affiliation and CU behaviors, we tested whether parental harshness or low warmth moderated these pathways.
Fearlessness and low social affiliation uniquely predicted increases in CU behaviors, but not oppositional-defiant behaviors, from ages 3 to 5. Moreover, there was evidence for differential moderation of the fear pathway by harsh parenting, such that harsh parenting predicted increases in CU behaviors in fearless children but increases in oppositional-defiant behaviors in fearful children.
Fearlessness and low social affiliation contribute to the development of CU behaviors. Harsh parenting can exacerbate the risky fearlessness pathway. Preventative interventions aimed at reducing risk for CU behaviors and persistent aggression and antisocial behavior should target socioaffiliative processes and provide parents with strategies and training to manage and scaffold rule-compliant behavior when children show low fearful arousal.
The Wisconsin Twin Project encompasses nearly 30 years of longitudinal research that spans infancy to early adulthood. The twin sample was recruited from statewide birth records for birth cohorts 1989–2004. We summarize early recruitment, assessment, retention and recently completed twin neuroimaging studies. In addition to the focal twins, longitudinal data were also collected from two parents and nontwin siblings. Our adolescent and young adult neuroimaging sample (N = 600) completed several previous behavioral and environmental assessments, beginning shortly after birth. The extensive phenotyping is meant to support a range of empirical investigations with potentially differing theoretical perspectives.
Parental alcohol dependence is a significant risk factor for harsh caregiving behaviors; however, it is unknown whether and how harsh caregiving changes over time and across parenting contexts for alcohol-dependent mothers. Furthermore, to our knowledge, no studies have examined whether and how distinct dimensions of child characteristics, such as negative emotionality modulate harsh caregiving among alcohol-dependent mothers. Guided by parenting process models, the present study examined how two distinct domains of children's negative emotionality—fear and frustration—moderate the association between maternal alcohol dependence and maternal harshness across discipline and free-play contexts. A high-risk sample of 201 mothers and their two-year-old children were studied over a one-year period. Results from latent difference score analyses indicated that harsh parenting among alcohol-dependent mothers increased over time in the more stressful discipline context, but not in the parent–child play context. This effect was maintained even after controlling for other parenting risk factors, including other forms of maternal psychopathology. Furthermore, this increase in harsh parenting was specific to alcohol-dependent mothers whose children were displaying high levels of anger and frustration. Findings provide support for specificity in conceptualizations of child negative emotionality and parenting contexts as potential determinants of maladaptive caregiving among alcohol-dependent mothers.
The Longitudinal Israeli Study of Twins (LIST) focuses on the developmental, genetic and environmental contributions to individual differences in children’s and adolescents’ social behavior. Key variables have been empathy, prosocial behavior, temperament and values. Another major goal of LIST has been to study gene–environment correlations, mainly concerning parenting. LIST includes 1657 families of Hebrew-speaking Israeli twins who have participated at least once in the study. Children’s environment and their development are assessed in a multivariate, multimethod fashion, including observed, parent-reported and self-reported data. The current article summarizes and updates recent findings from LIST. For example, LIST provided evidence for the heritability of human values with the youngest sample to date, and the first genetic investigation of adolescents’ identity formation. Finally, future aims of LIST are discussed.
The Boston University Twin Project (BUTP) uses a multimethod, longitudinal approach to study the role of genetic and environmental factors on the development of child temperament and related behaviors in early childhood. There are two phases in this project. The first, described in the previous Twin Research and Human Genetics special issue on twin registries, focused on activity level and comprised over 300 twin pairs assessed in the home and laboratory at ages 2 and 3. In this article, we describe subject recruitment, sample characteristics, and study procedures and measures of the second phase of the BUTP. This recent study focuses more broadly on the development of multiple temperament dimensions and explores associations between temperament trajectories, parenting and child adjustment in a new cohort of approximately 300 twin pairs assessed at 3, 4 and 5 years of age.
We investigated changes in self-representation depending on language in Friulian–Italian bilinguals. The Temperament and Character Inventory (TCI) and the Junior-TCI were administered respectively to 24 adults and 25 children, both in Friulian and in Italian, at a distance of two weeks from each other. Variations in TCI were detected: both adults and children scored higher in Self-Directedness (a character trait) when using Italian than Friulian. Similar findings were observed for Novelty-Seeking (a temperament trait) in children and Cooperativeness (another character trait) in adults. Results are discussed considering previous studies on bilingualism and within the frame of the Friulian sociolinguistic context.
This study examined whether the interaction between parenting and inhibitory control predicts hyperactivity-impulsivity and inattention in 195 children. Observation data of positive parenting were collected at 4 years, and mother reports of coercive parenting at 5 years, inhibitory control at 6 years, and hyperactivity-impulsivity/inattention at 7 years were obtained. The common and unique variance of hyperactivity-impulsivity and inattention symptoms were examined as outcomes using a bifactor model. Results indicated that positive parenting practices predicted lower levels of hyperactivity-impulsivity/inattention behaviors at age 7 only when children's inhibitory control was high. These results support the vantage sensitivity model, which posits that some individuals show an increased sensitivity to positive experiences exclusively, and support the appropriateness of a targeted prevention approach in early childhood.
Temperament and personality traits, including negative emotionality/neuroticism, may represent risk factors for eating disorders. Further, risk factors may differ by sex. We examined longitudinal temperament/personality pathways of risk for purging and binge eating in youth stratified by sex using data from a large-scale prospective study.
Temperament, borderline personality features, sensation seeking, ‘big five’ personality factors, and depressive symptoms were measured at five time points from early childhood to adolescence in 5812 adolescents (3215 females; 2597 males) in the Avon Longitudinal Study of Parents and Children. We conducted univariate analyses with these predictors of binge eating and purging at 14 and 16 years for total and sex-stratified samples. We used structural equation modeling (SEM) to fit data to a path analysis model of hypothesized associations.
Of the total sample, 12.54% engaged in binge eating and 7.05% in purging by 16 years. Prevalence was much greater and increased dramatically for females from 14 years (7.50% binge eating; 2.40% purging) to 16 years (15.80% binge eating; 9.50% purging). For both sexes, borderline personality, depressive symptoms and lower emotional stability predicted eating disorder behaviors; sensation seeking and conscientiousness were also significant predictors for females. SEM identified an ‘emotional instability’ pathway for females from early childhood into adolescence (RMSEA = 0.025, TLI = 0.937 and CFI = 0.970).
Binge eating and purging are common in female and male adolescents. Early temperament/personality factors related to difficulty regulating emotions were predictive of later adolescent eating disorder behaviors. Results have important clinical implications for eating disorder prevention and intervention.
The Wisconsin Twin Project comprises multiple longitudinal studies that span infancy to early adulthood. We summarize recent papers that show how twin designs with deep phenotyping, including biological measures, can inform questions about phenotypic structure, etiology, comorbidity, heterogeneity, and gene–environment interplay of temperamental constructs and mental and physical health conditions of children and adolescents. The general framework for investigations begins with rich characterization of early temperament and follows with study of experiences and exposures across childhood and adolescence. Many studies incorporate neuroimaging and hormone assays.
Individual differences in social-emotional functioning emerge early and have long-term implications for developmental adaptation and competency. Research is needed that specifies multiple early risk factors and outcomes simultaneously to demonstrate specificity. Using multigroup longitudinal path analysis in a sample of typically developing children (N = 541), we examined child temperament dimensions (surgency, negative affectivity, and regulation/effortful control) and maternal anxiety in infancy and age 2 as predictors of child externalizing, internalizing, dysregulation, and competence behaviors at age 3. Four primary patterns emerged. First, there was stability in temperament dimensions and maternal anxiety from infancy to age 3. Second, negative affectivity was implicated in internalizing problems and surgency in externalizing problems. Third, effortful control at age 2 was a potent mediator of maternal anxiety in infancy on age 3 outcomes. Fourth, there was suggestive evidence for transactional effects between maternal anxiety and child effortful control. Most pathways operated similarly for boys and girls, with some differences, particularly for surgency. These findings expand our understanding of the roles of specific temperamental domains and postnatal maternal anxiety in a range of social-emotional outcomes in the preschool period, and have implications for efforts to enhance the development of young children's social-emotional functioning and reduce risk for later psychopathology.
While child self-regulation is shaped by the environment (e.g., the parents’ caregiving behaviors), children also play an active role in influencing the care they receive, indicating that children's individual differences should be integrated in models relating early care to children's development. We assessed 409 children's observed temperamental behavioral inhibition (BI), effortful control (EC), and the primary caregiver's parenting at child ages 3 and 5. Parents reported on child behavior problems at child ages 3, 5, and 8. Mediation analyses were conducted to examine relations between child temperament and parenting in predicting child problems. BI at age 3 was positively associated with structured parenting at age 5, which was negatively related to child internalizing and attention-academic problems at age 8. In contrast, parenting at child age 3 did not predict child BI or EC at age 5, nor did age 3 EC predict parenting at age 5. Findings indicate that child behavior may shape the development of caregiving and, in turn, long-term child adjustment, suggesting that studies of caregiving and child outcomes should consider the role of child temperament toward developing more informative models of child–environment interplay.
Maternal pre-pregnancy weight has been related with young singletons’ cognitive and behavioral development, but it is not clear if it has an effect on temperament. We used a twin cohort to evaluate the association between maternal pre-pregnancy body mass index (BMI) and infants’ temperament. The mothers of 834 twins answered questions regarding their pre-pregnancy BMI and their 0- to 18-month-old children’s temperament using the Revised Infant Behavior Questionnaire. Three temperamental dimensions were examined: activity level, distress to limitation and duration of orienting. The relationship between maternal pre-pregnancy BMI and each temperamental component was investigated by means of multilevel mixed-effects linear regression analysis. We found no clear evidence of an association of maternal pre-pregnancy BMI with twins’ temperament. The development of temperament is influenced by a large number of factors, probably different from those influencing children’s emotional and behavioral development.
Emotion dysregulation characterizes many forms of psychopathology. Patterns of dysregulation occur as a function of a developmental process in which normative and adaptive emotion regulation skills fail to become part of the child's behavioral repertoire due to biological, psychological, and contextual processes and experiences. Here we highlight the processes involved in the dysregulation of temperamental anger and frustration that become core features of externalizing problems and place children at risk for more serious forms of psychopathology. We imbed these processes in a larger self-regulatory framework, and we discuss how they influence mental as well as physical health, using data from our 20-year longitudinal study following a large cohort of children into young adulthood. Recommendations are made for future research involving the integration of biological systems with mental and physical health outcomes.
Maternal mental health during pregnancy and postpartum predicts later emotional and behavioural problems in children. Even though most perinatal mental health problems begin before pregnancy, the consequences of preconception maternal mental health for children's early emotional development have not been prospectively studied.
We used data from two prospective Australian intergenerational cohorts, with 756 women assessed repeatedly for mental health problems before pregnancy between age 13 and 29 years, and during pregnancy and at 1 year postpartum for 1231 subsequent pregnancies. Offspring infant emotional reactivity, an early indicator of differential sensitivity denoting increased risk of emotional problems under adversity, was assessed at 1 year postpartum.
Thirty-seven percent of infants born to mothers with persistent preconception mental health problems were categorised as high in emotional reactivity, compared to 23% born to mothers without preconception history (adjusted OR 2.1, 95% CI 1.4–3.1). Ante- and postnatal maternal depressive symptoms were similarly associated with infant emotional reactivity, but these perinatal associations reduced somewhat after adjustment for prior exposure. Causal mediation analysis further showed that 88% of the preconception risk was a direct effect, not mediated by perinatal exposure.
Maternal preconception mental health problems predict infant emotional reactivity, independently of maternal perinatal mental health; while associations between perinatal depressive symptoms and infant reactivity are partially explained by prior exposure. Findings suggest that processes shaping early vulnerability for later mental disorders arise well before conception. There is an emerging case for expanding developmental theories and trialling preventive interventions in the years before pregnancy.
Findings as to whether individuals’ experiences of physical maltreatment from their parents in childhood predict their own perpetration of physical maltreatment toward their children in adulthood are mixed. Whether the maltreatment experienced is severe versus moderate or mild may relate to the strength of intergenerational associations. Furthermore, understanding of the roles of possible mediators (intervening mechanisms linking these behaviors) and moderators of the intervening mechanisms (factors associated with stronger or weaker mediated associations) is still relatively limited. These issues were examined in the present study. Mediating mechanisms based on a social learning model included antisocial behavior as assessed by criminal behaviors and substance use (alcohol and drug use), and the extent to which parental angry temperament moderated any indirect effects of antisocial behavior was also examined. To address these issues, data were used from Generations 2 and 3 of a prospective three-generational study, which is an extension of the Oregon Youth Study. Findings indicated modest intergenerational associations for severe physical maltreatment. There was a significant association of maltreatment history, particularly severe maltreatment with mothers’ and fathers’ delinquency. However, neither delinquency nor substance use showed significant mediational effects, and parental anger as a moderator of mediation did not reach significance.
Individual animals behave differently from one another, especially when confronting challenges such as changes in diet (e.g. weaning), environment (e.g. moving from pasture to feedlot) and social grouping (e.g. movement to lactating group after parturition). Each of these challenges involves some element of novelty, impacting the welfare and productivity of the animal. Indeed, the large individual variability in the development and expression of feeding behaviour cannot be fully explained by differences in genetics, management practices, body size or growth rate. In this review we outline evidence that individual variability in feeding behaviour is associated with the personality of the individual. We focus on three key personality traits: exploration, fear or reactivity and sociability. Individuals differ in how much they explore their feeding environment, with more exploratory individuals being less reactive to novel situations. Feeding behaviour can be impaired in individuals that are especially reactive to a change in their environment, change in diet or handling or restraint by humans. The social environment is also a major factor affecting how individuals express their behaviour. Sociability of the individual, including dominant-subordinate and affiliative relationships, affects how individuals make foraging decisions, gain access to feed and adopt particular social strategies to maintain or adjust feeding patterns when the social environment changes. Personality traits such as exploration, boldness and sociability also affect the use of social information when learning where, how or what to eat. Our review highlights the implications of feeding behaviour variability for the welfare and productivity of the individual, and how an understanding of personality can help tailor management to the needs of the individual.