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171.
BackgroundAdolescent motherhood is accompanied by a constellation of risk factors that translate into developmental risk for the off-spring. Socioeconomic risk that is associated with adolescent motherhood as well as maternal interactive behaviors may contribute to the impact of adolescent motherhood on children’s developmental outcome.ObjectiveTherefore, the aim of the current study was to investigate differences in children’s cognitive development between children of adolescent and adult mothers in their first two years of life and to examine whether socioeconomic risk (e.g. such as educational and financial problems) and/or maternal sensitivity mediate developmental differences between children of adolescent and adult mothers.MethodsAdolescent mothers (<21 years; N = 64) and adult mothers (>25 years; N = 34) and their infants were included in the current study. Child cognitive development and maternal sensitivity were assessed at three different time points (T1: mean child age 5.26 months; T2: mean child age 14.69 months; T3: mean child age 21.16 months).ResultsChildren of adult mothers showed better cognitive performance at T3 compared to children of adolescent mothers but not at T1 and T2. A multiple mediation model including socioeconomic risk and maternal sensitivity as serial mediators demonstrated that the effect of adolescent motherhood on cognitive development was mediated in a causal effect chain with socioeconomic risk negatively affecting maternal sensitivity and maternal sensitivity affecting children’s cognitive development.DiscussionThe present findings demonstrate that maternal interactive behaviors are not only a simple predictor of cognitive development but may also act as a mediator of the association between more distal variables such as socioeconomic risk and cognitive development in adolescent mothers. This supports the need to promote prevention and intervention programs for adolescent mothers during the early postpartum period to reduce socioeconomic problems and enhance maternal interactive behaviors.  相似文献   
172.
This study addressed the development of language-mediated categorization longitudinally, on a sample of Serbian-speaking children aged 16–20 months. Twenty four children were tested 3 consecutive times on: categorization of unknown objects with a shared label and a similar shape; and categorization of unknown objects with a shared label, but no visual similarity. The task was embedded in a game-like activity which included real object manipulation, categorization of novel objects labeled with made-up names, and socio-pragmatic cues provided by the experimenter. Our results indicate that an average child develops the ability to categorize novel objects with a similar shape and a shared label around 16 months of age, whereas for novel objects with a shared label, but no visual similarity, this ability is acquired sometime between 18 and 20 months of age. Our results partly confirm research findings obtained in other languages, thus emphasizing the need for cross-linguistic and cross-cultural validation of all language-related developmental studies.  相似文献   
173.
Media-multitasking involves simultaneous engagement with information streams from multiple media sources, and is most prevalent in young adults. Heavy media-multitasking has been associated with differential performance on tasks involving attentional control and working memory relative to light media-multitasking. The aim of the present study was to systematically investigate relationships between executive functions and self-reported media-multitasking. Healthy participants (N?=?112, aged 18–25, male N?=?36) completed a battery of 10 traditional executive function tasks, that included assessments of attentional inhibition, response inhibition, working memory, and cognitive flexibility. Scores on the individual executive function tasks were correlated against frequency of self-reported media-multitasking, but no significant relationships were found. Trait anxiety, however, was found to be significantly associated with greater frequency of self-reported media-multitasking. The present study found no evidence of a relationship between the frequency of self-reported media-multitasking and executive functioning. The possible reasons for this are discussed.  相似文献   
174.
Guided internet CBT (iCBT) is a promising treatment for depression; however, it is less well known through what mechanisms iCBT works. Two possible mediators of change are the acquisition of cognitive skills and increases in behavioral activation. We report results of an 8-week waitlist controlled trial of guided iCBT, and test whether early change in cognitive skills or behavioral activation mediated subsequent change in depression. The sample was 89 individuals randomized to guided iCBT (n = 59) or waitlist (n = 30). Participants were 75% female, 72% Caucasian, and 33 years old on average. The PHQ9 was the primary outcome measure. Mediators were the Competencies of Cognitive Therapy Scale–Self Report and the Behavioral Activation Scale for Depression–Short Form. Treatment was Beating the Blues plus manualized coaching. Outcomes were analyzed using linear mixed models, and mediation with a bootstrap resampling approach. The iCBT group was superior to waitlist, with large effect sizes at posttreatment (Hedges’ g = 1.45). Dropout of iCBT was 29% versus 10% for waitlist. In the mediation analyses, the acquisition of cognitive skills mediated subsequent depression change (indirect effect = -.61, 95% bootstrapped biased corrected CI: -1.47, -0.09), but increases in behavioral activation did not. iCBT is an effective treatment for depression, but dropout rates remain high. Change in iCBT appears to be mediated by improvements in the use of cognitive skills, such as critically evaluating and restructuring negative thoughts.  相似文献   
175.
Procrastination is a common problem among university students, with at least half of the population reporting great difficulties initiating or completing tasks and assignments. Procrastination can have a negative impact on course grades and the ability to achieve a university degree, but can also lead to psychological distress. Cognitive behavior therapy (CBT) is believed to reduce procrastination, but few studies have investigated its effectiveness in a regular clinical setting. The current study explored its effects using a pragmatic randomized controlled trial comparing treatment delivered during 8 weeks as self-guided CBT via the Internet (ICBT) or as group CBT. In total, 92 university students with severe procrastination were included in the study (registered as a clinical trial on Clinicaltrials.gov: NCT02112383). Outcome measures on procrastination, depression, anxiety, and well-being were distributed at pre- and posttreatment as well as 6-month follow-up. An outcome measure of procrastination was administered weekly. Linear mixed and fixed effects models were calculated, along with improvement and deterioration rates. The results showed large within-group effect sizes on procrastination, Cohen’s d of 1.29 for ICBT, 95% Confidence Interval (CI) [0.81, 1.74], and d of 1.24 for group CBT, 95% CI [0.76, 1.70], and small to moderate benefits for depression, anxiety, and well-being. In total, 33.7% were regarded as improved at posttreatment and 46.7% at follow-up. No differences between conditions were observed after the treatment period, however, participants in group CBT continued or maintained their improvement at follow-up, while participants in self-guided ICBT showed some signs of deterioration. The findings from the current study suggest that CBT might be an effective treatment for those struggling with severe procrastination, but that a group format may be better for some to sustain their benefits over time and that the clinical significance of the results need to be investigated further.  相似文献   
176.
We investigated treatment effects on parenting self-efficacy and parent cognitive errors, and whether these parent cognitions are related to short- and long-term outcomes in parenting behaviors in psychosocial treatment for youth with attention-deficit/hyperactivity disorder, predominantly inattentive presentation (ADHD-I). In a randomized controlled trial across two sites (University of California, San Francisco, and University of California, Berkeley), 199 children between the ages of 7 and 11 were randomized to the Child Life and Attention Skills (CLAS; n = 74) program, parent-focused treatment (PFT; n = 74), or treatment as usual (TAU; n = 51). Parents reported on self-efficacy, cognitive errors, positive parenting, and negative parenting prior to treatment, immediately after treatment, and in the next school year at follow-up. Compared to TAU, CLAS and PFT had higher posttreatment parenting self-efficacy, and CLAS alone had lower posttreatment parent cognitive errors. At follow-up, only CLAS had improved parent cognitive errors compared to TAU. No other between-group differences were found in parenting self-efficacy or cognitive errors. Improved parenting self-efficacy was associated with improved posttreatment negative parenting outcomes for PFT and CLAS, and improved parent cognitive errors were also related to improvements in positive and negative posttreatment parenting outcomes for CLAS. Posttreatment parenting self-efficacy mediated follow-up negative parenting outcomes for CLAS and posttreatment parent cognitive errors mediated improved follow-up positive and negative parenting outcomes for CLAS. PFT and CLAS led to enhanced parenting self-efficacy, and CLAS appears especially robust in improving parent cognitive errors both in the short and long term. Pathways provide support for the possibility of parent cognitions as mediators of treatment effects on parenting; clinical focus on such cognitions may be useful.  相似文献   
177.
To provide more refined diagnostic feedback with collateral information in item response times (RTs), this study proposed joint modelling of attributes and response speed using item responses and RTs simultaneously for cognitive diagnosis. For illustration, an extended deterministic input, noisy ‘and’ gate (DINA) model was proposed for joint modelling of responses and RTs. Model parameter estimation was explored using the Bayesian Markov chain Monte Carlo (MCMC) method. The PISA 2012 computer-based mathematics data were analysed first. These real data estimates were treated as true values in a subsequent simulation study. A follow-up simulation study with ideal testing conditions was conducted as well to further evaluate model parameter recovery. The results indicated that model parameters could be well recovered using the MCMC approach. Further, incorporating RTs into the DINA model would improve attribute and profile correct classification rates and result in more accurate and precise estimation of the model parameters.  相似文献   
178.
The maximum likelihood classification rule is a standard method to classify examinee attribute profiles in cognitive diagnosis models (CDMs). Its asymptotic behaviour is well understood when the model is assumed to be correct, but has not been explored in the case of misspecified latent class models. This paper investigates the asymptotic behaviour of a two-stage maximum likelihood classifier under a misspecified CDM. The analysis is conducted in a general restricted latent class model framework addressing all types of CDMs. Sufficient conditions are proposed under which a consistent classification can be obtained by using a misspecified model. Discussions are also provided on the inconsistency of classification under certain model misspecification scenarios. Simulation studies and a real data application are conducted to illustrate these results. Our findings can provide some guidelines as to when a misspecified simple model or a general model can be used to provide a good classification result.  相似文献   
179.
Negative conditional stimulus (CS) valence acquired during fear conditioning may enhance fear relapse and is difficult to remove as it extinguishes slowly and does not respond to the instruction that unconditional stimulus (US) presentations will cease. We examined whether instructions targeting CS valence would be more effective. In Experiment 1, an image of one person (CS+) was paired with an aversive US, while another (CS?) was presented alone. After acquisition, participants were given positive information about the CS+ poser and negative information about the CS? poser. Instructions reversed the pattern of differential CS valence present during acquisition and eliminated differential electrodermal responding. In Experiment 2, we compared positive and negative CS revaluation by providing positive/negative information about the CS+ and neutral information about CS?. After positive revaluation, differential valence was removed and differential electrodermal responding remained intact. After negative revaluation, differential valence was strengthened and differential electrodermal responding was eliminated. Unexpectedly, the instructions did not affect the reinstatement of differential electrodermal responding.  相似文献   
180.
Abstract

Episodic memory problems are the hallmark of cognitive ageing in normal elderly people. Learning of new material is worse in pathological cognitive ageing, such as dementia and its preliminary states (mild cognitive impairment). Because episodic learning is crucial to preserve independent living in the elderly, rehabilitation programmes for everyday memory problems are welcomed. The scope of scientific interest has switched from treatment to prevention. We claim that lifestyle interventions are the most direct way to preserve cognition. We summarize evidence for changes in nutrition and exercise. In addition, psychological interventions for elderly people with normal or pathological cognitive ageing are available. Recent meta-analyses found lacking evidence of transfer to everyday life and long-term effects. We critically assess these meta-analyses. We propose theoretically derived experimental interventions relying on spared learning mechanisms. As an example we report visual-imagery training showing positive effects in a randomized control trial, using individual memory diaries on memory improvement.  相似文献   
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