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1.
Curr Psychol ; : 1-18, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37359660

RESUMO

Reward processing undergoes marked changes in adolescence, with social interactions representing a powerful source of reward. Reward processing is also an important factor in the development of social anxiety disorder, a condition that most commonly first appears in adolescence. This study investigated the relationship between age, social reward processing and social anxiety in a cross-sectional sample of female participants (N = 80) aged 13-34. Participants performed two versions of a probabilistic reward anticipation task, in which a speeded response could result in different probabilities of receiving either social or monetary rewarding feedback. Participants also completed self-report assessments of social reward value, trait anxiety and social anxiety symptoms. At high reward probabilities, performance on both reward tasks showed a quadratic effect of age, with the fastest responses at around 22-24 years. A similar quadratic effect was found for subjective liking ratings of both reward stimuli, although these were not associated with performance. Social anxiety was not associated with a subjective liking of the rewards but did predict performance on both tasks at all reward probabilities. Age-related variation in reward processing was not accounted for by age-related variation in social anxiety symptoms, suggesting that, while both social anxiety and age were associated with variation in reward processing, their effects were largely independent. Together, these findings provide evidence that social reward processing continues to develop across adolescence and that individual differences in social anxiety should be considered when considering reward sensitivity during this period. Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-023-04551-y.

2.
Dev Sci ; 26(3): e13330, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36194156

RESUMO

Understanding how learning changes during human development has been one of the long-standing objectives of developmental science. Recently, advances in computational biology have demonstrated that humans display a bias when learning to navigate novel environments through rewards and punishments: they learn more from outcomes that confirm their expectations than from outcomes that disconfirm them. Here, we ask whether confirmatory learning is stable across development, or whether it might be attenuated in developmental stages in which exploration is beneficial, such as in adolescence. In a reinforcement learning (RL) task, 77 participants aged 11-32 years (four men, mean age = 16.26) attempted to maximize monetary rewards by repeatedly sampling different pairs of novel options, which varied in their reward/punishment probabilities. Mixed-effect models showed an age-related increase in accuracy as long as learning contingencies remained stable across trials, but less so when they reversed halfway through the trials. Age was also associated with a greater tendency to stay with an option that had just delivered a reward, more than to switch away from an option that had just delivered a punishment. At the computational level, a confirmation model provided increasingly better fit with age. This model showed that age differences are captured by decreases in noise or exploration, rather than in the magnitude of the confirmation bias. These findings provide new insights into how learning changes during development and could help better tailor learning environments to people of different ages. RESEARCH HIGHLIGHTS: Reinforcement learning shows age-related improvement during adolescence, but more in stable learning environments compared with volatile learning environments. People tend to stay with an option after a win more than they shift from an option after a loss, and this asymmetry increases with age during adolescence. Computationally, these changes are captured by a developing confirmatory learning style, in which people learn more from outcomes that confirm rather than disconfirm their choices. Age-related differences in confirmatory learning are explained by decreases in stochasticity, rather than changes in the magnitude of the confirmation bias.


Assuntos
Aprendizagem , Reforço Psicológico , Masculino , Humanos , Adolescente , Recompensa , Punição
3.
BMJ Open ; 12(12): e065977, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585150

RESUMO

INTRODUCTION: Scalable psychological treatments to address depression among adolescents are urgently needed. This is particularly relevant to low-income and middle-income countries where 90% of the world's adolescents live. While digital delivery of behavioural activation (BA) presents a promising solution, its feasibility, acceptability and effectiveness among adolescents in an African context remain to be shown. METHODS AND ANALYSIS: This study is a two-arm single-blind individual-level randomised controlled pilot trial to assess the feasibility, acceptability and initial efficacy of digitally delivered BA therapy among adolescents with depression. The intervention has been coproduced with adolescents at the study site. The study is based in the rural northeast of South Africa in the Bushbuckridge subdistrict of Mpumalanga province. A total of 200 adolescents with symptoms of mild to moderately severe depression on the Patient Health Questionnaire Adolescent Version will be recruited (1:1 allocation ratio). The treatment group will receive BA therapy via a smartphone application (the Kuamsha app) supported by trained peer mentors. The control group will receive an enhanced standard of care. The feasibility and acceptability of the intervention will be evaluated using a mixed methods design, and signals of the initial efficacy of the intervention in reducing symptoms of depression will be determined on an intention-to-treat basis. Secondary objectives are to pilot a range of cognitive, mental health, risky behaviour and socioeconomic measures; and to collect descriptive data on the feasibility of trial procedures to inform the development of a further larger trial. ETHICS AND DISSEMINATION: This study has been approved by the University of the Witwatersrand Human Research Ethics Committee (MED20-05-011) and the Oxford Tropical Research Ethics Committee (OxTREC 34-20). Study findings will be published in scientific open access peer-reviewed journals, presented at scientific conferences and communicated to participants, their caregivers, public sector officials and other relevant stakeholders. TRIAL REGISTRATION NUMBERS: This trial was registered on 19 November 2020 with the South African National Clinical Trials Registry (DOH-27-112020-5741) and the Pan African Clinical Trials Registry (PACTR202206574814636).


Assuntos
Terapia Comportamental , Depressão , Humanos , Adolescente , Depressão/terapia , Depressão/psicologia , África do Sul , Projetos Piloto , Método Simples-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Trop Med Int Health ; 26(11): 1333-1344, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34270856

RESUMO

The transitional period of adolescence has long been associated with physical, social and behavioural change. During this time, adolescents start to develop their own self-identity, make important life decisions and acquire the necessary skills to successfully transition to adulthood. More recently, advances in brain imaging technology have enabled increased understanding of structural and functional changes in the human brain during this developmental period, and how they relate to social, emotional, motivational and cognitive development. The ability to integrate these developing cognitive processes in increasingly complex social contexts is a key aspect of mature decision-making, which has implications for adolescent health, educational, economic and social outcomes. Insights from the field of developmental cognitive neuroscience could increase our understanding of this influential stage of life and thus inform potential interventions to promote adolescent health, a critical goal for global health research. Many social changes occur during adolescence and the social environment shapes both brain and cognitive development and the decisions adolescents make. Thus, it is important to study adolescent neurocognitive development in socio-cultural context. Yet, despite evidence from Western studies that socio-cultural and economic factors impact on adolescent neurocognitive development, existing studies of adolescent neurocognitive development in sub-Saharan Africa are relatively scarce. We summarise research findings from Western and sub-Saharan African contexts and highlight areas where research is lacking. Longitudinal studies from more diverse global samples will be needed to build a comprehensive model of adolescent development, that characterises both commonalities in developmental trajectories, as well as the way these can meaningfully differ between both individuals and contexts.


Assuntos
Desenvolvimento do Adolescente , Serviços de Saúde do Adolescente , Encéfalo/crescimento & desenvolvimento , Adolescente , África Subsaariana , Feminino , Humanos , Masculino
5.
Dev Sci ; 23(2): e12889, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31336006

RESUMO

Dopamine transmission in the prefrontal cortex (PFC) supports working memory (WM), the temporary holding, processing and manipulation of information in one's mind. The gene coding the catechol-O-methyltransferase (COMT) enzyme, which degrades dopamine, in particular in the PFC, has a common single nucleotide polymorphism leading to two versions of the COMT enzyme which vary in their enzymatic activity. The methionine (Met) allele has been associated with higher WM performance and lower activation of the PFC in executive function tasks than the valine (Val) allele. In a previous study, COMT genotype was associated with performance on verbal and visuospatial WM tasks in adults, as well as with performance on a novel social WM paradigm that requires participants to maintain and manipulate information about the traits of their friends or family over a delay. Here, data collected in children and adolescents (N = 202) were compared to data from the adult sample (N = 131) to investigate possible age differences in genetic associations. Our results replicate and extend previous work showing that the pattern of superior WM performance observed in Met/Met adults emerges during development. These findings are consistent with a decrease in prefrontal dopamine levels during adolescence. Developmentally moderated genetic effects were observed for both visuospatial and social WM, even when controlling for non-social WM performance, suggesting that the maintenance and manipulation of social information may also recruit the dopamine neurotransmitter system. These findings show that development should be considered when trying to understand the impact of genetic polymorphisms on cognitive function.


Assuntos
Catecol O-Metiltransferase/genética , Dopamina/genética , Memória de Curto Prazo/fisiologia , Adolescente , Adulto , Criança , Cognição/fisiologia , Feminino , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Córtex Pré-Frontal
6.
PLoS Comput Biol ; 13(8): e1005684, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28800597

RESUMO

Previous studies suggest that factual learning, that is, learning from obtained outcomes, is biased, such that participants preferentially take into account positive, as compared to negative, prediction errors. However, whether or not the prediction error valence also affects counterfactual learning, that is, learning from forgone outcomes, is unknown. To address this question, we analysed the performance of two groups of participants on reinforcement learning tasks using a computational model that was adapted to test if prediction error valence influences learning. We carried out two experiments: in the factual learning experiment, participants learned from partial feedback (i.e., the outcome of the chosen option only); in the counterfactual learning experiment, participants learned from complete feedback information (i.e., the outcomes of both the chosen and unchosen option were displayed). In the factual learning experiment, we replicated previous findings of a valence-induced bias, whereby participants learned preferentially from positive, relative to negative, prediction errors. In contrast, for counterfactual learning, we found the opposite valence-induced bias: negative prediction errors were preferentially taken into account, relative to positive ones. When considering valence-induced bias in the context of both factual and counterfactual learning, it appears that people tend to preferentially take into account information that confirms their current choice.


Assuntos
Tomada de Decisões/fisiologia , Retroalimentação Psicológica/fisiologia , Aprendizagem/fisiologia , Reforço Psicológico , Adulto , Biologia Computacional , Feminino , Humanos , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
7.
Neurosci Biobehav Rev ; 70: 106-120, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27545755

RESUMO

Social cognitive processes are critical in navigating complex social interactions and are associated with a network of brain areas termed the 'social brain'. Here, we describe the development of social cognition, and the structural and functional changes in the social brain during adolescence, a period of life characterised by extensive changes in social behaviour and environments. Neuroimaging and behavioural studies have demonstrated that the social brain and social cognition undergo significant development in human adolescence. Development of social cognition and the social brain are discussed in the context of developments in other neural systems, such as those implicated in motivational-affective and cognitive control processes. Successful transition to adulthood requires the rapid refinement and integration of these processes and many adolescent-typical behaviours, such as peer influence and sensitivity to social exclusion, involve dynamic interactions between these systems. Considering these interactions, and how they vary between individuals and across development, could increase our understanding of adolescent brain and behavioural development.


Assuntos
Comportamento Social , Adolescente , Comportamento do Adolescente , Encéfalo , Cognição , Humanos , Neuroimagem
8.
PLoS Comput Biol ; 12(6): e1004953, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27322574

RESUMO

Adolescence is a period of life characterised by changes in learning and decision-making. Learning and decision-making do not rely on a unitary system, but instead require the coordination of different cognitive processes that can be mathematically formalised as dissociable computational modules. Here, we aimed to trace the developmental time-course of the computational modules responsible for learning from reward or punishment, and learning from counterfactual feedback. Adolescents and adults carried out a novel reinforcement learning paradigm in which participants learned the association between cues and probabilistic outcomes, where the outcomes differed in valence (reward versus punishment) and feedback was either partial or complete (either the outcome of the chosen option only, or the outcomes of both the chosen and unchosen option, were displayed). Computational strategies changed during development: whereas adolescents' behaviour was better explained by a basic reinforcement learning algorithm, adults' behaviour integrated increasingly complex computational features, namely a counterfactual learning module (enabling enhanced performance in the presence of complete feedback) and a value contextualisation module (enabling symmetrical reward and punishment learning). Unlike adults, adolescent performance did not benefit from counterfactual (complete) feedback. In addition, while adults learned symmetrically from both reward and punishment, adolescents learned from reward but were less likely to learn from punishment. This tendency to rely on rewards and not to consider alternative consequences of actions might contribute to our understanding of decision-making in adolescence.


Assuntos
Comportamento do Adolescente/fisiologia , Envelhecimento/fisiologia , Tomada de Decisões/fisiologia , Modelos Educacionais , Recompensa , Adolescente , Adulto , Algoritmos , Criança , Simulação por Computador , Técnicas de Apoio para a Decisão , Feminino , Humanos , Masculino , Adulto Jovem
9.
J Adolesc ; 43: 5-14, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26043167

RESUMO

Adolescents have been shown to be particularly sensitive to peer influence. However, the data supporting these findings have been mostly limited to the impact of peers on risk-taking behaviours. Here, we investigated the influence of peers on performance of a high-level cognitive task (relational reasoning) during adolescence. We further assessed whether this effect on performance was dependent on the identity of the audience, either a friend (peer) or the experimenter (non-peer). We tested 24 younger adolescent (10.6-14.2 years), 20 older adolescent (14.9-17.8 years) and 20 adult (21.8-34.9 years) female participants. The presence of an audience affected adolescent, but not adult, relational reasoning performance. This audience effect on adolescent performance was influenced by the participants' age, task difficulty and the identity of the audience. These findings may have implications for education, where adolescents often do classwork or homework in the presence of others.


Assuntos
Comportamento do Adolescente/psicologia , Cognição , Tomada de Decisões , Amigos/psicologia , Influência dos Pares , Adolescente , Adulto , Fatores Etários , Criança , Feminino , Humanos , Testes Neuropsicológicos , Análise e Desempenho de Tarefas , Adulto Jovem
10.
J Psychopharmacol ; 29(9): 961-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25990558

RESUMO

3,4-methylenedioxy-N-methylamphetamine (MDMA) produces diverse pro-social effects. Cognitive training methods rooted in Eastern contemplative practices also produce these effects through the development of a compassionate mindset. Given this similarity, we propose that one potential mechanism of action of MDMA in psychotherapy is through enhancing effects on intrapersonal attitudes (i.e. pro-social attitudes towards the self). We provide a preliminary test of this idea. Recreational MDMA (ecstasy) users were tested on two occasions, having consumed or not consumed ecstasy. Self-critical and self-compassionate responses to self-threatening scenarios were assessed before (T1) and after (T2) ecstasy use (or non-use), and then after compassionate imagery (T3). Moderating roles of dispositional self-criticism and avoidant attachment were examined. Separately, compassionate imagery and ecstasy produced similar sociotropic effects, as well as increases in self-compassion and reductions in self-criticism. Higher attachment-related avoidance was associated with additive effects of compassionate imagery and ecstasy on self-compassion. Findings were in line with MDMA's neuropharmacological profile, its phenomenological effects and its proposed adjunctive use in psychotherapy. However, although conditions were balanced, the experiment was non-blind and MDMA dose/purity was not determined. Controlled studies with pharmaceutically pure MDMA are still needed to test these effects rigorously.


Assuntos
Afeto/efeitos dos fármacos , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Adulto , Empatia/efeitos dos fármacos , Feminino , Humanos , Masculino , Psicofarmacologia/métodos , Psicoterapia/métodos
11.
Soc Cogn Affect Neurosci ; 10(6): 777-82, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25190703

RESUMO

The catechol-O-methyltransferase (COMT) enzyme is a major determinant of prefrontal dopamine levels. The Val(158)Met polymorphism affects COMT enzymatic activity and has been associated with variation in executive function and affective processing. This study investigated the effect of COMT genotype on the flexible modulation of the balance between processing self-generated and processing stimulus-oriented information, in the presence or absence of affective distractors. Analyses included 124 healthy adult participants, who were also assessed on standard working memory (WM) tasks. Relative to Val carriers, Met homozygotes made fewer errors when selecting and manipulating self-generated thoughts. This effect was partly accounted for by an association between COMT genotype and visuospatial WM performance. We also observed a complex interaction between the influence of affective distractors, COMT genotype and sex on task accuracy: male, but not female, participants showed a sensitivity to the affective distractors that was dependent on COMT genotype. This was not accounted for by WM performance. This study provides novel evidence of the role of dopaminergic genetic variation on the ability to select and manipulate self-generated thoughts. The results also suggest sexually dimorphic effects of COMT genotype on the influence of affective distractors on executive function.


Assuntos
Afeto/fisiologia , Atenção/fisiologia , Catecol O-Metiltransferase/genética , Genótipo , Polimorfismo Genético , Pensamento/fisiologia , Adulto , Função Executiva/fisiologia , Feminino , Heterozigoto , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos , Adulto Jovem
12.
J Affect Disord ; 174: 265-71, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25527997

RESUMO

BACKGROUND: Affective bias is a common feature of depressive disorder. However, a lack of longitudinal studies means that the temporal relationship between affective bias and depression is not well understood. One group where studies of affective bias may be particularly warranted is the adolescent offspring of depressed parents, given observations of high rates of depression and a severe and impairing course of disorder in this group. METHODS: A two wave panel design was used in which adolescent offspring of parents with recurrent depression completed a behavioural task assessing affective bias (The Affective Go/No Go Task) and a psychiatric interview. The affective processing of adolescents with current, prior and future depressive disorder was compared to that of adolescents free from disorder. RESULTS: Adolescents with current depression and those who developed depression at follow-up made more commission errors for sad than happy targets compared to adolescents free from disorder. There was no effect of prior depression on later affective processing. LIMITATIONS: Small cell sizes meant we were unable to separately compare those with new onset and recurrent depressive disorder. CONCLUSIONS: Valence-specific errors in behavioural inhibition index future vulnerability to depression in adolescents already at increased risk and may represent a measure of affective control. Currently depressed adolescents show a similar pattern of affective bias or deficits in affective control.


Assuntos
Afeto , Filho de Pais com Deficiência/psicologia , Pais/psicologia , Adolescente , Comportamento do Adolescente , Viés , Estudos de Casos e Controles , Transtorno Depressivo/psicologia , Feminino , Seguimentos , Humanos , Entrevista Psicológica , Estudos Longitudinais , Masculino , Fatores de Risco
13.
Cogn Dev ; 28(3): 290-299, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24027353

RESUMO

Recent research on risky decision-making in adults has shown that both the risk in potential outcomes and their valence (i.e., whether those outcomes involve gains or losses) exert dissociable influences on decisions. We hypothesised that the influences of these two crucial decision variables (risk and valence) on decision-making would vary developmentally during adolescence. We adapted a risk-taking paradigm that provides precise metrics for the impacts of risk and valence. Decision-making in 11-16 year old female adolescents was influenced by both risk and valence. However, their influences assumed different developmental patterns: the impact of valence diminished with age, while there was no developmental change in the impact of risk. These different developmental patterns provide further evidence that risk and valence are fundamentally dissociable constructs and have different influences on decisions across adolescence.

14.
Conscious Cogn ; 22(1): 264-71, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23376348

RESUMO

Introspection, or metacognition, is the capacity to reflect on our own thoughts and behaviours. Here, we investigated how one specific metacognitive ability (the relationship between task performance and confidence) develops in adolescence, a period of life associated with the emergence of self-concept and enhanced self-awareness. We employed a task that dissociates objective performance on a visual task from metacognitive ability in a group of 56 participants aged between 11 and 41 years. Metacognitive ability improved significantly with age during adolescence, was highest in late adolescence and plateaued going into adulthood. Our results suggest that awareness of one's own perceptual decisions shows a prolonged developmental trajectory during adolescence.


Assuntos
Cognição , Psicologia do Adolescente , Autoimagem , Teoria da Mente , Adolescente , Adulto , Fatores Etários , Análise de Variância , Feminino , Humanos , Testes de Inteligência , Masculino , Curva ROC , Fatores Sexuais , Percepção Visual , Adulto Jovem
15.
PLoS One ; 5(11): e13706, 2010 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-21085661

RESUMO

BACKGROUND: Flashbacks (intrusive memories of a traumatic event) are the hallmark feature of Post Traumatic Stress Disorder, however preventative interventions are lacking. Tetris may offer a 'cognitive vaccine' [1] against flashback development after trauma exposure. We previously reported that playing the computer game Tetris soon after viewing traumatic material reduced flashbacks compared to no-task [1]. However, two criticisms need to be addressed for clinical translation: (1) Would all games have this effect via distraction/enjoyment, or might some games even be harmful? (2) Would effects be found if administered several hours post-trauma? Accordingly, we tested Tetris versus an alternative computer game--Pub Quiz--which we hypothesized not to be helpful (Experiments 1 and 2), and extended the intervention interval to 4 hours (Experiment 2). METHODOLOGY/PRINCIPAL FINDINGS: The trauma film paradigm was used as an experimental analog for flashback development in healthy volunteers. In both experiments, participants viewed traumatic film footage of death and injury before completing one of the following: (1) no-task control condition (2) Tetris or (3) Pub Quiz. Flashbacks were monitored for 1 week. Experiment 1: 30 min after the traumatic film, playing Tetris led to a significant reduction in flashbacks compared to no-task control, whereas Pub Quiz led to a significant increase in flashbacks. Experiment 2: 4 hours post-film, playing Tetris led to a significant reduction in flashbacks compared to no-task control, whereas Pub Quiz did not. CONCLUSIONS/SIGNIFICANCE: First, computer games can have differential effects post-trauma, as predicted by a cognitive science formulation of trauma memory. In both Experiments, playing Tetris post-trauma film reduced flashbacks. Pub Quiz did not have this effect, even increasing flashbacks in Experiment 1. Thus not all computer games are beneficial or merely distracting post-trauma - some may be harmful. Second, the beneficial effects of Tetris are retained at 4 hours post-trauma. Clinically, this delivers a feasible time-window to administer a post-trauma "cognitive vaccine".


Assuntos
Ciência Cognitiva/métodos , Rememoração Mental , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Adolescente , Adulto , Afeto , Computadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filmes Cinematográficos , Inquéritos e Questionários , Análise e Desempenho de Tarefas , Adulto Jovem
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