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Chi Chiao - One of the best experts on this subject based on the ideXlab platform.
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adolescent premarital sex and health outcomes among taiwanese youth perception of best friends sexual behavior and the Contextual effect
Aids Care-psychological and Socio-medical Aspects of Aids\ hiv, 2011Co-Authors: Chi Chiao, Chinchun YiAbstract:This study explores premarital sex among adolescents and its health outcomes in a typical East Asian society, Taiwan. As a collective society in terms of cultural heritage, a particular target of this study was perceived peer pressure and its Contextual Influence. The data were taken from the Taiwan Youth Project, 2004 and 2007, and never married youth aged 20 years constituted our sample (N=3530). Best friends' sexual behavior and other context-related factors, such as school attendance and community participation, are presumed to Influence adolescent premarital sex as well as their health status. Logistic regression models show a positive and significant association between the perception of friends' sexual behavior and the likelihood of adolescent premarital sex engagement, after adjusting for the youth's own sex-related experience and attitudes, individual characteristics, and family background. The analysis also confirms that school attendance and community participation are significantly associated ...
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adolescent premarital sex and health outcomes among taiwanese youth perception of best friends sexual behavior and the Contextual effect
Aids Care-psychological and Socio-medical Aspects of Aids\ hiv, 2011Co-Authors: Chi ChiaoAbstract:This study explores premarital sex among adolescents and its health outcomes in a typical East Asian society, Taiwan. As a collective society in terms of cultural heritage, a particular target of this study was perceived peer pressure and its Contextual Influence. The data were taken from the Taiwan Youth Project, 2004 and 2007, and never married youth aged 20 years constituted our sample (N=3530). Best friends' sexual behavior and other context-related factors, such as school attendance and community participation, are presumed to Influence adolescent premarital sex as well as their health status. Logistic regression models show a positive and significant association between the perception of friends' sexual behavior and the likelihood of adolescent premarital sex engagement, after adjusting for the youth's own sex-related experience and attitudes, individual characteristics, and family background. The analysis also confirms that school attendance and community participation are significantly associated with a lower likelihood of having premarital sex. Furthermore, adolescent premarital sex was found to be linked to the perceived health status of the youth (self-rated health, smoking, and drinking), as expected. These findings demonstrate the importance of peers and social context, which suggests that HIV prevention and health promotion programs for youth need to take friendship networks and social context into consideration.
Ichiro Kawachi - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a social capital questionnaire for adolescent students scq as
PLOS ONE, 2014Co-Authors: Paula Cristina Pelli Paiva, Ichiro Kawachi, Haroldo Neves De Paiva, Paulo Messias De Oliveira Filho, Joel Alves Lamounier, Efigenia Ferreira E Ferreira, Raquel Conceicao Ferreira, Patricia Maria ZarzarAbstract:Objectives Social capital has been studied due to its Contextual Influence on health. However, no specific assessment tool has been developed and validated for the measurement of social capital among 12-year-old adolescent students. The aim of the present study was to develop and validate a quick, simple assessment tool to measure social capital among adolescent students.
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school social fragmentation economic deprivation and social cohesion and adolescent physical inactivity a longitudinal study
PLOS ONE, 2014Co-Authors: Roman Pabayo, Michel Janosz, Sherri Bisset, Ichiro KawachiAbstract:Objectives To examine the independent Influence of school economic deprivation, social fragmentation, and social cohesion on the likelihood of participating in no physical activity among students. Methods Data are from a large-scale longitudinal study of schools based in disadvantaged communities in Quebec, Canada. Questionnaires were administered every year between 2002 and 2008 among n = 14,924 students aged 12 to 18 from a sample of 70 schools. Cross-sectional and longitudinal analyses were conducted. Multilevel modeling was utilized to account for the clustering of students within schools. Schools were categorized as being low, moderate or high economic deprivation, social fragmentation and social cohesion. Those who indicated that they do no participate in any physical activity during the week were identified as being physically inactive. Results In baseline multilevel cross-sectional analyses, adolescents attending schools in the highest (compared to the lowest) levels of socioeconomic deprivation and social fragmentation were more likely to be physically inactive (OR = 1.33, 95% CI = 1.03, 1.72; and OR = 1.24, 95% CI = 0.98, 1.56, respectively). Conversely, students attending schools with the highest cohesion were less likely to be physically inactive (OR = 0.78, 95% CI = 0.61, 0.99). In longitudinal analysis, physically active students who attended schools with the highest social fragmentation were more likely to become physically inactive over two years (OR = 1.65, 95% CI = 1.09, 2.51). Conclusion The school socioeconomic environment appears to be an important Contextual Influence on participation in no physical activity among adolescents. Following adolescents beyond two years is necessary to determine if these environments have a lasting effect on physical activity behavior.
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neighborhood social capital and crime victimization comparison of spatial regression analysis and hierarchical regression analysis
Social Science & Medicine, 2012Co-Authors: Daisuke Takagi, Kenichi Ikeda, Ichiro KawachiAbstract:Crime is an important determinant of public health outcomes, including quality of life, mental well-being, and health behavior. A body of research has documented the association between community social capital and crime victimization. The association between social capital and crime victimization has been examined at multiple levels of spatial aggregation, ranging from entire countries, to states, metropolitan areas, counties, and neighborhoods. In multilevel analysis, the spatial boundaries at level 2 are most often drawn from administrative boundaries (e.g. Census tracts in the U.S.). One problem with adopting administrative definitions of neighborhoods is that it ignores spatial spillover. We conducted a study of social capital and crime victimization in one ward of Tokyo city, using a Spatial Durbin Model with an inverse-distance weighting matrix that assigned each respondent a unique level of “exposure” to social capital based on all other residents’ perceptions. The study is based on a postal questionnaire sent to 20–69 years old residents of Arakawa Ward, Tokyo. The response rate was 43.7%. We examined the Contextual Influence of generalized trust, perceptions of reciprocity, two types of social network variables, as well as two principal components of social capital (constructed from the above four variables). Our outcome measure was self-reported crime victimization in the last five years. In the Spatial Durbin Model, we found that neighborhood generalized trust, reciprocity, supportive networks and two principal components of social capital were each inversely associated with crime victimization. By contrast, a multilevel regression performed with the same data (using administrative neighborhood boundaries) found generally null associations between neighborhood social capital and crime. Spatial regression methods may be more appropriate for investigating the Contextual Influence of social capital in homogeneous cultural settings such as Japan.
Chinchun Yi - One of the best experts on this subject based on the ideXlab platform.
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adolescent premarital sex and health outcomes among taiwanese youth perception of best friends sexual behavior and the Contextual effect
Aids Care-psychological and Socio-medical Aspects of Aids\ hiv, 2011Co-Authors: Chi Chiao, Chinchun YiAbstract:This study explores premarital sex among adolescents and its health outcomes in a typical East Asian society, Taiwan. As a collective society in terms of cultural heritage, a particular target of this study was perceived peer pressure and its Contextual Influence. The data were taken from the Taiwan Youth Project, 2004 and 2007, and never married youth aged 20 years constituted our sample (N=3530). Best friends' sexual behavior and other context-related factors, such as school attendance and community participation, are presumed to Influence adolescent premarital sex as well as their health status. Logistic regression models show a positive and significant association between the perception of friends' sexual behavior and the likelihood of adolescent premarital sex engagement, after adjusting for the youth's own sex-related experience and attitudes, individual characteristics, and family background. The analysis also confirms that school attendance and community participation are significantly associated ...
Olivier Piguet - One of the best experts on this subject based on the ideXlab platform.
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beyond the face how context modulates emotion processing in frontotemporal dementia subtypes
Brain, 2018Co-Authors: Fiona Kumfor, Agustin Ibanez, Rosalind Hutchings, Jessica L Hazelton, John R Hodges, Olivier PiguetAbstract:The importance of assessing social cognition to characterize dementia syndromes is increasingly recognized, with lower social cognition capacity associated with reduced functional independence and greater carer burden. Emotion recognition is impaired in both behavioural-variant frontotemporal dementia and semantic dementia, yet the social and behavioural changes observed in these syndromes in everyday situations varies. To date, most studies have investigated isolated, context-free stimuli indexing recognition of facial emotions only. Here, we aimed to investigate how Contextual information (i.e. emotional body language) Influences emotion recognition, within the framework of the Social Context Network Model. Thirty-one patients with frontotemporal dementia (19 behavioural-variant frontotemporal dementia; 12 semantic dementia) and 20 healthy age- and education-matched controls were assessed on three tasks which varied Contextual cues: (i) face alone; (ii) context alone; and (iii) face embedded in context. Voxel-based morphometry was used to identify neural correlates of task performance. Our results demonstrated that both behavioural-variant frontotemporal dementia and semantic dementia patients performed worse than controls in recognizing emotions from face alone and context alone. Importantly, performance differed when faces were presented in context. While both behavioural-variant frontotemporal dementia and semantic dementia patients performed similarly to controls on congruent items (i.e. face emotion and body emotion are the same) (P-values > 0.05), patients with behavioural-variant frontotemporal dementia performed worse than both controls (P < 0.001) and patients with semantic dementia (P = 0.044) for incongruent items (i.e. face emotion and body emotion are different). Neuroimaging analyses revealed that abnormal Contextual Influence was associated with lower integrity of the right parahippocampal gyrus/amygdala and left precentral gyrus. Together, these results indicate that patients with behavioural-variant frontotemporal dementia are over-reliant on external Contextual information. Conversely, in semantic dementia and controls, Contextual Influence varies, with the degree of Contextual Influence appearing to be mediated, at least in part, by the facial expression depicted. The profile in behavioural-variant frontotemporal dementia is reminiscent of the 'environmental dependency syndrome' described in frontal lesion patients. It also converges with recent evidence of abnormal face perception in this group. From a theoretical perspective, our findings demonstrate that the capacity to incorporate Contextual body language is dependent on the integrity of both Contextual association brain regions (i.e. parahippocampal gyrus), as well as regions necessary for processing dynamic body movements. Clinically, these results open new avenues for rehabilitation of social impairments in dementia.
Jan B Engelmann - One of the best experts on this subject based on the ideXlab platform.
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Contextual Influence on confidence judgments in human reinforcement learning.
'Public Library of Science (PLoS)', 2019Co-Authors: Maël Lebreton, Karin Bacily, Stefano Palminteri, Jan B EngelmannAbstract:The ability to correctly estimate the probability of one's choices being correct is fundamental to optimally re-evaluate previous choices or to arbitrate between different decision strategies. Experimental evidence nonetheless suggests that this metacognitive process-confidence judgment- is susceptible to numerous biases. Here, we investigate the effect of outcome valence (gains or losses) on confidence while participants learned stimulus-outcome associations by trial-and-error. In two experiments, participants were more confident in their choices when learning to seek gains compared to avoiding losses, despite equal difficulty and performance between those two contexts. Computational modelling revealed that this bias is driven by the context-value, a dynamically updated estimate of the average expected-value of choice options, necessary to explain equal performance in the gain and loss domain. The biasing effect of context-value on confidence, revealed here for the first time in a reinforcement-learning context, is therefore domain-general, with likely important functional consequences. We show that one such consequence emerges in volatile environments, where the (in)flexibility of individuals' learning strategies differs when outcomes are framed as gains or losses. Despite apparent similar behavior- profound asymmetries might therefore exist between learning to avoid losses and learning to seek gains
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Contextual Influence on confidence judgments in human reinforcement learning - Fig 1
2019Co-Authors: Maël Lebreton, Karin Bacily, Stefano Palminteri, Jan B EngelmannAbstract:Experiment 1 Task Schematic, Learning and Confidence Results (A) Behavioral task. Successive screens displayed in one trial are shown from left to right with durations in ms. After a fixation cross, participants viewed a couple of abstract symbols displayed on both sides of a computer screen and had to choose between them. They were thereafter asked to report their confidence in their choice on a numerical scale (graded from 0 to 10). Finally, the outcome associated with the chosen symbol was revealed. (B) Task design and contingencies. (C) Performance. Trial by trial percentage of correct responses in the partial (left) and the complete (middle) information conditions. Filled colored areas represent mean ± sem; Right: Individual averaged performances in the different conditions. Connected dots represent individual data points in the within-subject design. The error bar displayed on the side of the scatter plots indicate the sample mean ± sem. (D) Confidence. Trial by trial confidence ratings in the partial (left) and the complete (middle) information conditions. Filled colored areas represent mean ± sem; Right: Individual averaged performances in the different conditions. Connected dots represent individual data points in the within-subject design. The error bar displayed on the side of the scatter plots indicate the sample mean ± sem.
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Contextual Influence on confidence judgments in human reinforcement learning - Fig 2
2019Co-Authors: Maël Lebreton, Karin Bacily, Stefano Palminteri, Jan B EngelmannAbstract:Experiment 2 Task Schematic, Learning and Confidence Results (A) Behavioral task. Successive screens displayed in one trial are shown from left to right with durations in ms. After a fixation cross, participants viewed a couple of abstract symbols displayed on both sides of a computer screen, and had to choose between them. They were thereafter asked to report their confidence in their choice on a numerical scale (graded from 50 to 100%). Finally, the outcome associated with the chosen symbol was revealed. (B) Task design and contingencies. (C) Performance. Trial by trial percentage of correct responses in the partial (left) and the complete (middle) information conditions. Filled colored areas represent mean ± sem; Right: Individual averaged performances in the different conditions. Connected dots represent individual data points in the within-subject design. The error bar displayed on the side of the scatter plots indicate the sample mean ± sem. (D) Confidence. Trial by trial confidence ratings in the partial (left) and the complete (middle) information conditions. Filled colored areas represent mean ± sem; Right: Individual averaged performances in the different conditions. Connected dots represent individual data points in the within-subject design. The error bar displayed on the side of the scatter plots indicate the sample mean ± sem.
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Contextual Influence on confidence judgments in human reinforcement learning
bioRxiv, 2018Co-Authors: Maël Lebreton, Karin Bacily, Stefano Palminteri, Jan B EngelmannAbstract:The ability to correctly estimate the probability of one9s choices being correct is fundamental to optimally re-evaluate previous choices or to arbitrate between different decision strategies. Experimental evidence nonetheless suggests that this metacognitive process -referred to as a confidence judgment- is susceptible to numerous biases. We investigate the effect of outcome valence (gains or losses) on confidence while participants learned stimulus-outcome associations by trial-and-error. In two experiments, we demonstrate that participants are more confident in their choices when learning to seek gains compared to avoiding losses. Importantly, these differences in confidence were observed despite objectively equal choice difficulty and similar observed performance between those two contexts. Using computational modelling, we show that this bias is driven by the context-value, a dynamically updated estimate of the average expected-value of choice options that has previously been demonstrated to be necessary to explain equal performance in the gain and loss domain. The biasing effect of context-value on confidence, also recently observed in the context of incentivized perceptual decision-making, is therefore domain-general, with likely important functional consequences.