860 resultados para Cognition in adolescence.
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Background. Adolescents' intentions to smoke are generally regarded as a valid and reliable predictor of subsequent smoking. This association is largely based on research with adults and needs a more detailed analysis for adolescents. Methods. Data on intentions and smoking status were collected as part of a longitudinal, birth-cohort study when the study members were 9, 11, 13, 15, 18, and 21 years of age. Results. The results showed that intention to smoke only had an important predictive power in the subgroup of previous nonsmokers. Among those already smoking (on a monthly basis or greater), previous level of smoking was a more important predictor of future behavior than intention to smoke. In addition, the effect of positive intention to smoke was nonlinear over age and had the greatest effect at age 15. Conclusion. The results indicated that in adolescence, measurement of intentions to smoke or not smoke cannot be assumed to be a general predictor of behavior at a later age for all groups of adolescents. (C) 2004 The Institute For Cancer Prevention and Elsevier Inc. All rights reserved.
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Aim: To determine the influence of breastfeeding on overweight and obesity in early adolescence. Methods: Data about breastfeeding duration, BMI of children at 14 years, and confounding variables, were collected from an ongoing longitudinal study of a birth cohort of 7776 children in Brisbane. Prevalence of overweight and obesity at 14 years was assessed according to duration of breastfeeding, with logistic regression being used to adjust for the influence of confounders. Results: Data were available for 3698 children, and those not included were significantly different in age, educational level, income, race, birthweight, and small-for-gestational-age status. Breastfeeding for longer than six months was protective of obesity (OR 0.6, 95% CI 0.4, 0.96) though not of overweight. When confounding variables were considered the effect size diminished and lost statistical significance OR 0.8 (95% CI 0.5, 1.3). Breastfeeding for less than 6 months had no effect on either obesity or overweight though a trend was found for increased prevalence of overweight at 14 years with shorter periods of breastfeeding. Conclusion: This investigation contributes to the gathering body of evidence that breastfeeding for longer than 6 months has a modest protective effect against obesity in adolescence.
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Objective: To assess whether cannabis use in adolescence and young adulthood is a contributory cause of schizophreniform psychosis in that it may precipitate psychosis in vulnerable individuals. Method: We reviewed longitudinal studies of adolescents and young adults that examined the relations between self-reported cannabis use and the risk of diagnosis with a psychosis or of reporting psychotic symptoms. We also reviewed studies that controlled for potential confounders, such as other forms of drug use and personal characteristics that predict an increased risk of psychosis. We assessed evidence for the biological plausibility of a contributory causal relation. Results: Evidence from 6 longitudinal studies in 5 countries shows that regular cannabis use predicts an increased risk of a schizophrenia diagnosis or of reporting symptoms of psychosis. These relations persisted after controlling for confounding variables, such as personal characteristics and other drug use. The relation did not seem to be a result of cannabis use to self-medicate symptoms of psychosis. A contributory causal relation is biologically plausible because psychotic disorders involve disturbances in the dopamine neurotransmitter systems with which the cannabinoid system interacts, as demonstrated by animal studies and one human provocation study. Conclusion: It is most plausible that cannabis use precipitates schizophrenia in individuals who are vulnerable because of a personal or family history of schizophrenia.
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Reciprocidade indivíduo-organização e afetividade são dois fenômenos presentes na vida organizacional e que se tornaram tópicos de pesquisa no campo de estudos do comportamento organizacional. Esse estudo teve como objetivo reforçar as evidências empíricas acerca das relações entre cognições de troca indivíduo-organização e afetividade no contexto de trabalho. Para tanto, foram submetidas à teste empírico cinco hipóteses inspiradas em um estudo inédito desenvolvido por Siqueira (2002b). Contou-se com a utilização de um questionário composto por cinco escalas validadas, referentes as variáveis do estudo, que avaliaram percepção de suporte organizacional (PSO), percepção de reciprocidade organizacional (PRO), comprometimento organizacional normativo (CON), satisfação no trabalho (STR) e comprometimento organizacional afetivo (COA). Participaram 275 profissionais, sendo 183 pertencentes ao setor administrativo e 92 ao setor administrativo-acadêmico de uma Instituição de Ensino Superior, situada na região do Grande ABCD Paulista e com inserção no estado de São Paulo. OS participantes do estudo tinham idade média de 32 anos, sendo a maioria (58,2%) do sexo feminino, com escolaridade em nível superior (39,6%) e tempo médio de trabalho na organização de quatro anos. Os dados coletados foram organizados em um banco de dados eletrônico para tratamento estatístico, quando se utilizou o aplicativo SPSS (Statistical Package for the Social Scienses). Foram realizadas análises descritivas das variáveis e análises de correlação e de regressão múltipla para os testes das cinco hipóteses. Todas as hipóteses foram confirmadas. Conclui-se então, que o presente estudo reforça as proposições de Siqueira (2002b) acerca da pertinência de se considerar os três conceitos analisados (PSO, PRO E CON) como integrantes do esquema mental de reciprocidade. Ainda, os resultados do estudo reafirmam as evidências acerca da capacidade preditiva do EMR sobre satisfação no trabalho e comprometimento organizacional afetivo. Por fim, a análise dos dados aponta percepção de suporte organizacional como sendo o componente cognitivo do EMR com maior poder de influência sobre satisfação no trabalho e comprometimento organizacional afetivo. Portanto, cognições acerca das relações de troca social com organizações antecedem satisfação e comprometimento afetivo que, por sua vez, são importantes fatores a favor da organização, contribuindo para sua efetividade.
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Para atingir os objetivos propostos, ou seja, levantar e descrever indicadores socioculturais de uma amostra de adolescentes em cumprimento de medida socioeducativa, e descrever características psicológicas e de personalidade dos adolescentes infratores, num estudo que pesquisou adolescentes em cumprimento de medida socioeducativa. O trabalho foi realizado em duas as etapas: na primeira, os 47 adolescentes participaram de uma entrevista semidirigida; na segunda, dez desses adolescentes foram selecionados e submetidos a um instrumento projetivo para investigação de aspectos da personalidade: o “desenho da Figura Humana” de Machower, adaptado por Van Kolck (1956; 1984). A discussão teórica dos resultados baseou-se numa abordagem psicanalítica pós-freudiana para a compreensão da adolescência tanto como fase do desenvolvimento humano como dos comportamentos antissociais. Os resultados do estudo corroboraram a teoria advinda da literatura psicológica que aborda padrões comuns no período da adolescência, fase em que ocorre um complexo de fatores individuais da maturidade biológica associados ao meio social/cultural e que, por sua vez, estabelecem relações com as instâncias psicológicas ou psíquicas do sujeito junto com as características específicas de cada indivíduo. Na busca da compreensão desses padrões comuns da amostra dos adolescentes infratores utilizados no presente estudo, foram levantados dados do perfil psicossocial, cultural e demográfico; dos aspectos psicossociais e aspectos psicodinâmicos e de características de personalidade. A título de conclusão, o estudo destacou a problemática do adolescente em conflito com a lei, associada às questões sociais, de saúde mental, além do desenvolvimento psíquico, sinalizando a necessidade de ações psicoprofiláticas voltadas para população infantil, jovem, agrupamentos familiares e para a comunidade que representa seu entorno.
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Development of the cerebral cortex is influenced by sensory experience during distinct phases of postnatal development known as critical periods. Disruption of experience during a critical period produces neurons that lack specificity for particular stimulus features, such as location in the somatosensory system. Synaptic plasticity is the agent by which sensory experience affects cortical development. Here, we describe, in mice, a developmental critical period that affects plasticity itself. Transient neonatal disruption of signaling via the C-terminal domain of "disrupted in schizophrenia 1" (DISC1)-a molecule implicated in psychiatric disorders-resulted in a lack of long-term potentiation (LTP) (persistent strengthening of synapses) and experience-dependent potentiation in adulthood. Long-term depression (LTD) (selective weakening of specific sets of synapses) and reversal of LTD were present, although impaired, in adolescence and absent in adulthood. These changes may form the basis for the cognitive deficits associated with mutations in DISC1 and the delayed onset of a range of psychiatric symptoms in late adolescence.
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Preface. The evolution of cognitive neuroscience has been spurred by the development of increasingly sophisticated investigative techniques to study human cognition. In Methods in Mind, experts examine the wide variety of tools available to cognitive neuroscientists, paying particular attention to the ways in which different methods can be integrated to strengthen empirical findings and how innovative uses for established techniques can be developed. The book will be a uniquely valuable resource for the researcher seeking to expand his or her repertoire of investigative techniques. Each chapter explores a different approach. These include transcranial magnetic stimulation, cognitive neuropsychiatry, lesion studies in nonhuman primates, computational modeling, psychophysiology, single neurons and primate behavior, grid computing, eye movements, fMRI, electroencephalography, imaging genetics, magnetoencephalography, neuropharmacology, and neuroendocrinology. As mandated, authors focus on convergence and innovation in their fields; chapters highlight such cross-method innovations as the use of the fMRI signal to constrain magnetoencephalography, the use of electroencephalography (EEG) to guide rapid transcranial magnetic stimulation at a specific frequency, and the successful integration of neuroimaging and genetic analysis. Computational approaches depend on increased computing power, and one chapter describes the use of distributed or grid computing to analyze massive datasets in cyberspace. Each chapter author is a leading authority in the technique discussed.
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Context: The cognitive side effects of medications with anticholinergic activity have been documented among older adults in a variety of clinical settings. However, there has been no systematic confirmation that acute or chronic prescribing of such medications lead to transient or permanent adverse cognitive outcomes. Objective: Evaluate the existing evidence regarding the effects of anticholinergic medications on cognition in older adults. Data sources: We searched the MEDLINE, OVID, and CINAHL databases from January, 1966 to January, 2008 for eligible studies. Study selection: Studies were included if the anticholinergic activity was systematically measured and correlated with standard measurements of cognitive performance. Studies were excluded if they reported case studies, case series, editorials, and review articles. Data extraction: We extracted the method used to determine anticholinergic activity of medications and its association with cognitive outcomes. Results: Twenty-seven studies met our inclusion criteria. Serum anticholinergic assay was the main method used to determine anticholinergic activity. All but two studies found an association between the anticholinergic activity of medications and either delirium, cognitive impairment or dementia. Conclusions: Medications with anticholinergic activity negatively affect the cognitive performance of older adults. Recognizing the anticholinergic activity of certain medications may represent a potential tool to improve cognition.
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Immigration disrupts an individual's support network; however, the stresses of the immigration process increase the need for social support. The presence of social support becomes essential for immigrant children and adolescents to cope with these important transitional circumstances. Friends are both sources of social support and models for behavior. Furthermore, friendship networks are known to have a significant influence on youths' functioning. Literature suggests that peer relations become more important in adolescence and friend support is related to child and adolescent well-being. Thus, friend relationships may be particularly important for immigrant youths who experience disruption in their friendship networks during the process of migration to another country. In addition to friendship networks and support, friend characteristics also need to be taken into consideration as important factors for immigrant youth adjustment. My study involved analyses of the effects of friend support and friend problem behaviors on emotional and behavioral functioning for elementary, middle, and high school age newly immigrant children and adolescents. ^ Immigrant children and adolescents (N = 503) were interviewed at schools by interviewers fluent in participants' languages. Structural Equation Modeling (SEM) analyses revealed that friend support and friend problem behaviors were related to children's self-esteem and externalizing behaviors. In addition, friend problem behavior alone predicted children's psychological symptoms and depression scores. Furthermore, age/grade was found to be a moderator for the relation between friend problem behavior and immigrant youth behavioral adjustment such that compared to elementary and high school cohorts, middle school youths showed more externalizing behaviors when they had friends performing problem behaviors. ^ Results supported the idea that both friend support and friend behavior are related to newly immigrant youths' emotional and behavioral adjustment. This study informs further research and interventions concerning the development of programs to facilitate immigrant youths' adjustment by revealing friendship factors related to their adaptation.^
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The purpose of this study was to determine the racial and ethnic differences on body image perceptions and weight concerns of fourth grade girls. A purposive sample of 182 fourth grade girls were eligible to participate, 166 were included in the data analysis. The Children's Eating Attitude Test (ChEAT) and a Dieting and Demographic Questionnaire (DDQ) were used to determine eating attitudes of fourth grade girls. A pictoral instrument that was modified from the original was used to assess body image. Anthropometric data was assessed and body mass index (BMI) values were used to classify subjects into percentiles. Results revealed that 56% of all fourth grade girls studied wanted to be thinner and 53% had tried to lose weight. Significantly more non-Hispanic white (NHW) girls reported wanting to be thinner than non-Hispanic black (NHB) and H girls (65.5% vs.32% and 47%, respectively, P=0.005) No significant racial/ethnic differences were revealed for the ChEAT scores. However, 19% of all subjects studied fell into the category indicative of anorexia nervosa. H girls who were less than the 85" %tile for BMI chose significantly smaller figures as their perceived body image (3.5±0.7) than both NHB and NHW girls (4.0±0.6 and 3.9±0.5, respectively, P<0.01). These findings demonstrated that weight concerns were prevalent among girls ages 9- 11 years. NHW and H girls may have more concerns about their body size and shape than their NHB counterparts. Implementing intervention programs at an early age may prevent eating disorders in adolescence and adulthood.
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Stressful developmental transitions related to identity and intimacy may have significant implications for adjustment in adolescence that last into young adulthood. Social and economic barriers experienced by minority adolescents have attracted attention as significant influences on normative developmental processes and psychosocial adjustment. The primary aim of this study was to describe significant relations among identity, intimacy, and adjustment in a sample of adolescents in an alternative school who were at elevated risk for problem behaviors. A sample of 120 multi-ethnic high school students responded to five self-administered questionnaires. In addition to describing significant gender differences in identity, and internalizing problems, this study documented that measures of identity accounted for significant variance in standard measures of internalizing problems using hierarchical multiple regression. The implications of these results for future research and practice are discussed.
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The objective of this research is to describe and analyze in literary corpus, the way we conceptualize emotions, especially anger. Using the assumptions of the call Cognitive Theory of Metaphor, present a general overview of cognition metaphor on the basis of Cognitive Linguistics, and in a deeper way, we analyze the metaphorical conceptualization of anger. The proposal embodied mind, prevalent in current cognitive science, is fundamental for studies involving mental simulation. Recent research shows that the metaphor is the result of cognitive processes that involve our perception sensorimotor combined with socio-cultural experiences. The ability to build via frequency standards for our experiments is crucial to our language, including metaphorical constructions. Such constructions are the result of cognitive processes that involve the relationship between image schemas and frames. Image schemas comes from our sensorimotor experience, which lists the limits of our bodies to the limits of our surroundings, and frames, in turn, comes from our ability to stock sociocultural events. The metaphorical construction is the result of this constant relationship between body, mind and culture, situating us in bodily experiences and cultural. By analyzing five national literary works, we created an analytical framework on how anger is understood, specifically in Portuguese language. The results are important to understand, through language, how culture is part of our cognition, in conjunction with the sensorimotor aspects.
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Academic demands, new social context, new routines and decrease of the parental control, are factors that may influence the sleep pattern of freshman students at the University. Medical students from the Federal University of Rio Grande do Norte (UFRN) have a full-time course, subjects with high-level content, and, at the first semester, classes begin at 7 a.m. This group composed by young adults who still suffering with delayed sleep phase, common in adolescence, indicating that this class schedule can be inappropriate at this age. The reduction of nocturnal sleep during school days, and the attempt to recover sleep on free days – social jet lag (JLS), suggests that in the first semester, students suffer from high sleep pressure. High sleep pressure may reflect on cognitive tasks and performance. Therefore, the aim of this study was to investigate the relationship between sleep pressure and the academic profile of medical students from the first semester of UFRN, characterizing this population socio-demographically and investigating possible impacts on therestactivity rhytm and academic performance. A sample of 88 students, healthy men and women awswered the following questionnaires: Pittsburgh Sleep Quality (PSQI), Epworth Sleepiness Scale (ESS), Horne & Ostberg Chronotype (HO), Munich Chronotype (MCTQ) and “Health and Sleep” adapted. Actigraphy was used during 14 days to make actogramas and obtain non-parametric variables of the rest-activity rhythm and the grades of the morning schedule were used as academic performance. The JLS was used as a measure of sleep pressure. Statistics significance level was 95%. The population was sociodemographic homogeneous. Most students have healthy lifestyle, practice physical activity, use car to go to the university and take between 15 and 30 minutes for this route. Regarding CSV, most were classify as intermediate (38.6%) and evening (32%) chronotypes, needs to nap during the week, suffer daytime sleepiness and have poor sleep quality. 83% of the sample has at least 1h JLS, which led us to divide into two groups: Group <2h JLS (N = 44) and Group ≥ 2h JLS (N = 44). The groups have differences only in chronotype, showing that most evening individuals have more JLS, however, no differences were found in relation to sociodemographic aspect, rest-activity rhythm or academic performance. The homogeneity of the sample was limited to compare the groups, however, is alarming that students already present in the first half: JLG, poor sleep quality and excessive daytime sleepiness, which can be accentuated through the university years, with the emergence of night shifts and increased academic demand. Interventionsaddressingthe importance of good sleep habits and the change of the class start time are strategies aimed to improve student’s health.