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61.
62.
This study examined whether adolescents' closeness to adoptive parents (APs) predicted attachment styles in close relationships outside their family during young adulthood. In a longitudinal study of domestic infant adoptions, closeness to adoptive mother and adoptive father was assessed in 156 adolescents (M = 15.7 years). Approximately 9 years later (M = 25.0 years), closeness to parents was assessed again as well as attachment style in their close relationships. Multilevel modeling was used to predict attachment style in young adulthood from the average and discrepancy of closeness to adolescents' adoptive mothers and fathers and the change over time in closeness to APs. Less avoidant attachment style was predicted by stronger closeness to both APs during adolescence. Increased closeness to APs over time was related to less anxiety in close relationships. Higher closeness over time to either AP was related to less avoidance and anxiety in close relationships.  相似文献   
63.
This study focuses on 422 African American families with two caregivers as children transition into adolescence. The family stress model was tested longitudinally using structural equation modeling. Results showed that economic stress was associated with economic pressure and depressive symptoms among caregivers, which in turn was related to caregiver conflict. Higher levels of conflict had a negative influence on parenting quality at Wave 2, and this was linked to adolescent functioning. The depressive symptomology of secondary caregivers (SCs) exerted a greater indirect effect in the models than that of primary caregivers (PCs) and had a direct relationship to adolescent's positive adjustment. Moderational effects of caregiver conflict on the link between economic pressure/adolescent outcomes and economic pressure/hostile parenting were also tested. The case for the importance of including PCs and SCs of children and adolescents in future research focusing on African American families facing economic hardship is made.  相似文献   
64.
Background: A high level of activity is commonplace in traditional subsistence societies. Physiological characteristics of individuals, including body composition and physical fitness, could be limiting factors when performing daily tasks.

Objectives: The study investigated the relationships between cardiorespiratory fitness, nutritional status and physical activity patterns, so as to test the hypothesis that these relationships are less straightforward in children than in adults.

Study design: Four different groups of individuals from rural Senegal were investigated: 99 10–13-year-old children of both sexes (11.1?±?1.5 years old) from two settings in Senegal (Lambaye and Podor), 43 adolescent girls (15.5?±?0.5 years), and 30 adult women (17–40 years).

Methods: Subjects undertook a step test, and anthropometric measurements were collected. Continuous heart rate (HR) monitoring was performed for 8–12?h. The flex-HR method was used to estimate levels of activity (per?cent of time spent under or over the flex-HR).

Results: Ten to 13-year-old children and adolescent girls presented slight degrees of malnutrition. Adult women were apparently not nutritionally deprived. Differences in cardiorespiratory fitness were found among 10–13-year-old children, while adult women performed better than adolescent girls. Children from Lambaye had a higher level of activity than children from Podor. Similarly, adult women were more active than adolescent girls. No relationships were found between cardiorespiratory or anthropometric measurements and per?cent of time spent above the flex-HR (>flex-HR) in 10–13-year-old children. In contrast, in adult women and adolescent girls, body composition and cardiorespiratory indices were significant predictors of activity levels.

Conclusion: Our data support the hypothesis that activity levels are less dependent upon physiological characteristics in children than in adults in traditional subsistence societies.  相似文献   
65.
Sleep spindles are intermittent bursts of 11-15 Hz EEG waves that occur during non-rapid eye movement sleep. Spindles are believed to help maintain sleep and to play a role in sleep-dependent memory consolidation. Here we applied an automated sleep spindle detection program to our large longitudinal sleep EEG dataset (98 human subjects, 6-18 years old, >2000 uninterrupted nights) to evaluate maturational trends in spindle wave frequency, density, amplitude, and duration. This large dataset enabled us to apply nonlinear as well as linear age models, thereby extending the findings of prior cross-sectional studies that used linear models. We found that spindle wave frequency increased with remarkable linearity across the age range. Central spindle density increased nonlinearly to a peak at age 15.1 years. Central spindle wave amplitude declined in a sigmoidal pattern with the age of fastest decline at 13.5 years. Spindle duration decreased linearly with age. Of the four measures, only spindle amplitude showed a sex difference in dynamics such that the age of most rapid decline in females preceded that in males by 1.4 years. This amplitude pattern, including the sex difference in timing, paralleled the maturational pattern for δ (1–4 Hz) wave power. We interpret these age-related changes in spindle characteristics as indicators of maturation of thalamocortical circuits and changes in sleep depth. These robust age-effects could facilitate the search for cognitive-behavioral correlates of spindle waveforms and might also help guide basic research on EEG mechanisms and postnatal brain maturation.SIGNIFICANCE STATEMENT The brain reorganization of adolescence produces massive changes in sleep EEG. These changes include the morphology and abundance of sleep spindles, an EEG marker of non-rapid eye movement sleep believed to reflect offline memory processes and/or protection of the sleep state. We analyzed >2000 nights of longitudinal sleep EEG from 98 subjects (age 6-18 years old) to investigate maturational changes in spindle amplitude, frequency, density, and duration. The large dataset enabled us to detect nonlinear as well as linear age changes. All measures showed robust age effects that we hypothesize reflect the maturation of thalamocortical circuits and decreasing sleep depth. These findings could guide further research into the cognitive-behavioral correlates of sleep spindles and their underlying brain mechanisms.  相似文献   
66.
Study ObjectivesTo prospectively examine changes in adolescent sleep before and during the COVID-19 pandemic in adolescents with and without ADHD.MethodsParticipants were 122 adolescents (ages 15–17; 61% male; 48% with ADHD). Parents reported on adolescents’ sleep duration and difficulties initiating and maintaining sleep (DIMS); adolescents reported on sleep patterns, sleep duration, delayed sleep/wake behaviors, and daytime sleepiness before (September 2019 to February 2020) and during (May–June 2020) COVID-19. Adolescents also reported on their health behaviors, COVID-19-related negative affect, and difficulties concentrating due to COVID-19.ResultsParents reported adolescents had more DIMS during COVID-19 than before COVID-19, with clinically elevated rates increasing from 24% to 36%. Both bedtimes and waketimes shifted later during COVID-19, and adolescents reported more delayed sleep/wake behaviors. Adolescents also reported less daytime sleepiness and longer school night sleep duration during COVID-19. In considering differences between adolescents with and without ADHD, adolescents with ADHD did not experience an increase in school night sleep duration and were less likely to obtain recommended sleep duration during COVID-19. In the full sample, controlling for ADHD status, COVID-19-related sadness/loneliness was associated with increases in DIMS, and spending less time outside and more COVID-19-related worries/fears were associated with increases in delayed sleep/wake behaviors during COVID-19.ConclusionsCOVID-19 had negative and positive impacts on adolescent sleep. Adolescents with ADHD did not experience the benefit of increased school night sleep duration during COVID-19 like adolescents without ADHD. Negative affect and health behaviors may be useful intervention targets for reducing negative impacts of COVID-19 for adolescent sleep.  相似文献   
67.
目的:探讨青少年早中期焦虑的发展特点及其与未来规划的动态关系。方法:从山东省选取8年级和10年级的学生共1077人作为追踪样本,采用状态—特质焦虑量表和未来规划问卷进行测查。运用交叉滞后回归分析考察了两变量之间的因果关系。结果:①在两次测量中,青少年中期的特质焦虑和状态焦虑水平均高于青少年早期;在间隔一年半的两次测量中,青少年早期的焦虑水平有所上升,青少年中期的焦虑水平保持相对稳定。②在焦虑和未来规划的纵向关系中,前测的状态焦虑和特质焦虑均负向预测后测的教育探索、教育投入、职业探索和职业投入;仅前测教育投入可以负向预测后测状态焦虑。结论:在青少年早中期,焦虑可以看作是个体未来规划的前因变量。  相似文献   
68.
Abstract

A new approach to assessing family attachment patterns is presented, using a composite measure of individual attachment representations based on the Bartholomew Attachment Interview. A cluster analysis yielded three different patterns in a sample of N = 37 families with a drug dependent adolescent (age 14 – 25) and both biological parents. A “triangulated” pattern (mothers: preoccupied; fathers: dismissing; adolescents: fearful) was found in 65% of the sample. A total of 19% showed an “insecure” pattern (mothers, fathers, and adolescents: fearful) and 16% a “near-secure” pattern (mothers and adolescents: secure; fathers preoccupied). Preliminary comparisons between these groups indicate differences in comorbid psychiatric disorders, in individual and family functioning, but not in addiction severity. There is a trend towards differences in outcome of family therapy. Implications for treatment and further research are discussed.  相似文献   
69.
ABSTRACT

This study investigated the effects of adolescents’ attachment security and reflective functioning (RF) (assessed by the adult attachment interview [AAI]) in the prediction of well-being in adulthood. Adolescents (N = 79; M = 14.6 years old; SD = 3.5 years) completed the AAI at Time 1 (T1), which was subsequently coded for inferred attachment experiences, narrative coherence, and RF by three nonoverlapping teams of raters. Participants completed the Psychological General Well-being Index at T1 and 8 years later (Time 2, T2). Analyses showed that (a) both adolescent narrative coherence and RF were significant predictors of almost all indices of well-being at T2 in adulthood; (b) both narrative coherence and RF indirectly linked inferred loving parental care and T2 well-being; (c) when included in the same model, RF was a significant indirect effect linking inferred loving parental care and T2 well-being. These findings contribute to theory in suggesting that both RF and narrative coherence are predictive of subsequent psychological well-being and operate as links between inferred parental care and subsequent adjustment. Possible mechanisms underlying these findings are discussed.  相似文献   
70.
ABSTRACT

Anxiety is the most prevalent psychiatric disturbance in childhood effecting typically 15–20% of all youth. It has been associated with attachment insecurity and reduced competence in peer relations. Prior work has been limited by including mainly White samples, relying on questionnaires, and applying a cross-sectional design. The present study addressed these limitations by considering how at-risk non-White youth (n = 34) responded to the Friends and Family Interview (FFI) in middle childhood and how this linked up with anxiety symptoms and an anxiety diagnosis three years later in early adolescence. Five dimensions of secure attachment, namely, (i) to mother, (ii) to father, (iii) coherence, (iv) developmental understanding, and (v) social competence and quality of contact with best friend in middle childhood, were found to correlate significantly (and negatively) with self-reported anxiety symptoms. Linear regression results showed independent influences of female gender, and (low) quality of best friend contact as the most efficient model predicting anxiety symptoms. Logistic regression results suggested a model that included female gender, low social competence, and immature developmental understanding as efficient predictors of an anxiety diagnosis, evident in only 18% of the sample. These results point to the usefulness of after-school programs for at-risk minority youth in promoting peer competence, developmental awareness, and minimizing anxiety difficulties.  相似文献   
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