Exposure to externalizing peers in early childhood: homophily and peer contagion processes.
(65/508)
Guided by a transactional model, we examined the predictors and effects of exposure to externalizing peers in a low-risk sample of preschoolers and kindergarteners. On the basis of daily observations of peer interactions, we calculated measures of total exposure to externalizing peers and measures of exposure to same- and other-sex externalizing peers. Analyses of predictors of externalizing peer exposure supported a homophily hypothesis for girls. Tests of peer contagion effects varied by sex, and exposure to externalizing peers predicted multiple problem behaviors for girls but not for boys. Sex differences were a function of children's own sex, but not of peers' sex. The study provides evidence of externalizing peer exposure effects in a low-risk sample of young children, notably for girls. (+info)
The impact of first-grade "friendship group" experiences on child social outcomes in the fast track program.
(66/508)
Many interventions for children's behavior problems successfully utilize a group format for social skills training, providing opportunities for practice and performance feedback from peers. Recent studies however, suggest that grouping aggressive children together may reduce intervention effectiveness or even increase risk. The present study examined the relative impact of children's own behavior and their experiences with peers in the first-grade "friendship groups" of Fast Track, a multi-component preventive intervention program. Two-hundred sixty-six children (56% minority, 29% female) participated in 55 friendship groups. Children's own positive and negative behavior in friendship groups was related to relative improvements in social cognitive skills, prosocial behavior, and aggression, assessed through child interviews, teacher ratings, and peer sociometric nominations. Results from hierarchical linear models also revealed that the amount of peer escalation children received for their disruptive behavior during sessions impeded some intervention gains, whereas mere exposure to other children's positive or negative behavior was rarely related to outcomes. (+info)
Association with delinquent peers: intervention effects for youth in the juvenile justice system.
(67/508)
Although association with delinquent peers is a recognized precursor to ongoing delinquency problems, youth in the juvenile justice system are commonly prescribed intervention services that aggregate delinquent youth. However, little is known about the process variables that mediate the relationship between aggregating youth in intervention settings and poor subsequent outcomes. We examined data from two randomized intervention trials (one male sample and one female sample) with delinquent adolescents placed either in Multidimensional Treatment Foster Care (MTFC) or in group care. Path analyses suggested that the MTFC youth had fewer associations with delinquent peers at 12 months than did the group care youth. Further, associating with delinquent peers during the course of the intervention mediated the relationship between group condition and 12-month delinquent peer association. Implications for the development of interventions with delinquent youth are discussed. (+info)
Peer contagion in interventions for children and adolescents: moving towards an understanding of the ecology and dynamics of change.
(68/508)
The influence of deviant peers on youth behavior is of growing concern, both in naturally occurring peer interactions and in interventions that might inadvertently exacerbate deviant development. The focus of this special issue is on understanding the moderating and mediating variables that account for peer contagion effects in interventions for youth. This set of nine innovative papers moves the field forward on three fronts: (1) Broadening the empirical basis for understanding the conditions under which peer contagion is more or less likely (that is, moderators of effects); (2) Identifying mechanisms that might account for peer contagion effects (mediators); and (3) Forging the methodological rigor that is needed to study peer contagion effects within the context of intervention trials. We propose an ecological framework for disentangling the effects of individuals, group interactions, and program contexts in understanding peer contagion effects. Finally, we suggest methodological enhancements to study peer contagion in intervention trials. (+info)
Social cognition: imitation, imitation, imitation.
(69/508)
Monkeys recognize when they are being imitated, but they seem unable to learn by imitation. These facts make sense if imitation is seen as two different capacities: social mirroring, when actions are matched and have social benefits; and learning by copying, when new behavioural routines are acquired by observation. (+info)
Socially transmitted mate preferences in a monogamous bird: a non-genetic mechanism of sexual selection.
(70/508)
There is increasing evidence that animals can acquire mate preferences through the use of public information, notably by observing (and copying) the mate preferences of others in the population. If females acquire preferences through social mechanisms, sexual selection could act very rapidly to spread the preference and drive elaboration of the preferred trait(s). Although there are reports of 'mate-choice copying' in polygynous species, there is no clear evidence for this process in monogamous species. Here, we investigated whether adult female zebra finches Taeniopygia guttata can socially acquire sexual preferences for individual males and, in a separate study, for a generalized trait (coloured leg bands) of males. In both studies, test females observed males in two simultaneous conditions: a ('chosen') mixed-sex situation in which a male was paired with a (model) female, and a ('unchosen') same-sex situation in which a male was paired with another male. In the first experiment, after two weeks of females observing males, test females significantly preferred individual males who had been paired with another female (i.e. chosen males). In the second experiment, test females significantly preferred novel males that were wearing the same leg band colour as the apparently chosen males. Our findings are consistent with the conclusion that female zebra finches' mate preferences are altered by public information. Our study implies that mate preferences can spread rapidly through populations by social mechanisms, affecting the strength of sexual selection in a monogamous species. (+info)
There exists an interplay between vaccine coverage, disease prevalence and the vaccinating behaviour of individuals. Moreover, because of herd immunity, there is also a strategic interaction between individuals when they are deciding whether or not to vaccinate, because the probability that an individual becomes infected depends upon how many other individuals are vaccinated. To understand this potentially complex interplay, a game dynamic model is developed in which individuals adopt strategies according to an imitation dynamic (a learning process), and base vaccination decisions on disease prevalence and perceived risks of vaccines and disease. The model predicts that oscillations in vaccine uptake are more likely in populations where individuals imitate others more readily or where vaccinating behaviour is more sensitive to changes in disease prevalence. Oscillations are also more likely when the perceived risk of vaccines is high. The model reproduces salient features of the time evolution of vaccine uptake and disease prevalence during the whole-cell pertussis vaccine scare in England and Wales during the 1970s. This suggests that using game theoretical models to predict, and even manage, the population dynamics of vaccinating behaviour may be feasible. (+info)
Explicit memory performance in infants of diabetic mothers at 1 year of age.
(72/508)
The aim of the present research was to investigate the impact of abnormal fetal environment on explicit memory performance. Based on animal models, it was hypothesized that infants of diabetic mothers (IDMs) experience perturbations in memory performance due to exposure to multiple neurologic risk factors including: chronic hypoxia, hyperglycemia/reactive hypoglycemia, and iron deficiency. Memory performance, as measured by the elicited/deferred imitation paradigm, was compared between 13 IDMs (seven females, six males; mean age 365 days, SD 11) and 16 typically developing children (seven females, nine males; mean age 379 days, SD 9). The IDM group was characterized by shorter gestational age (mean 38w, SD 2), greater standardized birthweight scores (mean 3797g, SD 947), and lower iron stores (mean ferritin concentration 87C microg/L, SD 68) in comparison with the control group (mean gestational age: 40w, SD 1; mean birthweight: 3639g, SD 348; mean newborn ferritin concentration 140 microg/L, SD 46). After statistically controlling for both gestational age and global cognitive abilities, IDMs demonstrated a deficit in the ability to recall multi-step event sequences after a delay was imposed. These findings highlight the importance of the prenatal environment on subsequent mnemonic behavior and suggest a connection between metabolic abnormalities during the prenatal period, development of memory, circuitry, and behavioral mnemonic performance. (+info)