YouTube vloggers set the stage: How public (non)compliance with COVID-19 regulations affects adolescents.

INTRODUCTION: YouTube vloggers may be important socialization figures, yet their influence on adolescents' health-related behaviors and cognitions is largely untested. In this two-study mixed-method project, we first assessed the extent of (non)compliance to COVID-19 regulations by vloggers on YouTube and how viewers reacted to this. Second, we experimentally assessed the effects of vlogger behavior paired with viewer evaluations on adolescents' COVID-19-related attitudes, intentions, and behavior. METHODS: For Study 1, we coded 240 vlogs of eight popular Dutch vloggers on YouTube recorded in the period of February 2020-March 2021. For our 2 × 2 between-subjects experiment in Study 2, Dutch adolescents (N = 285, Mage = 12.99, SD = 1.02, 41.8% girls) were randomly assigned to conditions in which they saw vlogs showing either compliance or noncompliance to COVID-19 regulations, and to conditions in which they saw either supportive or dismissive comments under these vlogs. RESULTS: Study 1: Vloggers' noncompliance with COVID-19 regulations was not uncommon and received relatively more viewer support than compliance, suggesting that portrayed noncompliance may be potentially influential. Study 2: Adolescents were more worried about COVID-19 after they watched a compliant (vs. noncompliant) vlogger. Also, vlogger noncompliance decreased adolescents' perceived importance of COVID-19 regulations and rule-setting for adolescents who identified strongly with the vloggers they watched. CONCLUSIONS: Vloggers' (non)compliance affects adolescents' COVID-19-related worrying, and attitudes and behavior of adolescents who identify with vloggers strongly. This seems concerning given the sometimes harmful and risky behaviors vloggers portray online but could potentially also be employed to encourage healthy behaviors.

Test-retest reliability of reinforcement learning parameters.

It has recently been suggested that parameter estimates of computational models can be used to understand individual differences at the process level. One area of research in which this approach, called computational phenotyping, has taken hold is computational psychiatry. One requirement for successful computational phenotyping is that behavior and parameters are stable over time. Surprisingly, the test-retest reliability of behavior and model parameters remains unknown for most experimental tasks and models. The present study seeks to close this gap by investigating the test-retest reliability of canonical reinforcement learning models in the context of two often-used learning paradigms: a two-armed bandit and a reversal learning task. We tested independent cohorts for the two tasks (N = 69 and N = 47) via an online testing platform with a between-test interval of five weeks. Whereas reliability was high for personality and cognitive measures (with ICCs ranging from .67 to .93), it was generally poor for the parameter estimates of the reinforcement learning models (with ICCs ranging from .02 to .52 for the bandit task and from .01 to .71 for the reversal learning task). Given that simulations indicated that our procedures could detect high test-retest reliability, this suggests that a significant proportion of the variability must be ascribed to the participants themselves. In support of that hypothesis, we show that mood (stress and happiness) can partly explain within-participant variability. Taken together, these results are critical for current practices in computational phenotyping and suggest that individual variability should be taken into account in the future development of the field.

Social influence in adolescence as a double-edged sword.

Social learning is fundamental to human development, helping individuals adapt to changing circumstances and cooperate in groups. During the formative years of adolescence, the social environment shapes people's socio-cognitive skills needed in adulthood. Although peer influence among adolescents is traditionally associated with risky and unruly conduct, with long-term negative effects on educational, economic and health outcomes, recent findings suggest that peers may also have a positive impact. Here, we present a series of experiments with 10-20-year-olds (n = 146) showing that positive and negative peer effects reflect a domain-general factor of social information use which declines during adolescence. Exposure to disobedient peers provoked rule breaking, and selfish peers reduced prosocial behaviour, particularly in early adolescence. However, compliant peers also promoted rule compliance and fair peers increased prosociality. A belief formation task further revealed that younger adolescents tend to assimilate social information, while older adolescents prioritize personal views. Our results highlight early adolescence as a key window for peer-based interventions to improve developmental trajectories.

Strategies for integrating disparate social information.

Social information use is widespread in the animal kingdom, helping individuals rapidly acquire useful knowledge and adjust to novel circumstances. In humans, the highly interconnected world provides ample opportunities to benefit from social information but also requires navigating complex social environments with people holding disparate or conflicting views. It is, however, still largely unclear how people integrate information from multiple social sources that (dis)agree with them, and among each other. We address this issue in three steps. First, we present a judgement task in which participants could adjust their judgements after observing the judgements of three peers. We experimentally varied the distribution of this social information, systematically manipulating its variance (extent of agreement among peers) and its skewness (peer judgements clustering either near or far from the participant's judgement). As expected, higher variance among peers reduced their impact on behaviour. Importantly, observing a single peer confirming a participant's own judgement markedly decreased the influence of other-more distant-peers. Second, we develop a framework for modelling the cognitive processes underlying the integration of disparate social information, combining Bayesian updating with simple heuristics. Our model accurately accounts for observed adjustment strategies and reveals that people particularly heed social information that confirms personal judgements. Moreover, the model exposes strong inter-individual differences in strategy use. Third, using simulations, we explore the possible implications of the observed strategies for belief updating. These simulations show how confirmation-based weighting can hamper the influence of disparate social information, exacerbate filter bubble effects and deepen group polarization. Overall, our results clarify what aspects of the social environment are, and are not, conducive to changing people's minds.

Victory is its own reward: oxytocin increases costly competitive behavior in schizophrenia.

BACKGROUND: Aberrant sensitivity to social reward may be an important contributor to abnormal social behavior that is a core feature of schizophrenia. The neuropeptide oxytocin impacts the salience of social information across species, but its effect on social reward in schizophrenia is unknown. METHODS: We used a competitive economic game and computational modeling to examine behavioral dynamics and oxytocin effects on sensitivity to social reward among 39 men with schizophrenia and 54 matched healthy controls. In a randomized, double-blind study, participants received one dose of oxytocin (40 IU) or placebo and completed a 35-trial Auction Game that quantifies preferences for monetary v. social reward. We analyzed bidding behavior using multilevel linear mixed models and reinforcement learning models. RESULTS: Bidding was motivated by preferences for both monetary and social reward in both groups, but bidding dynamics differed: patients initially overbid less compared to controls, and across trials, controls decreased their bids while patients did not. Oxytocin administration was associated with sustained overbidding across trials, particularly in patients. This drug effect was driven by a stronger preference for winning the auction, regardless of monetary consequences. Learning rate and response variability did not differ between groups or drug condition, suggesting that differences in bidding derive primarily from differences in the subjective value of social rewards. CONCLUSIONS: Our findings suggest that schizophrenia is associated with diminished motivation for social reward that may be increased by oxytocin administration.

Neurocognitive Development of Motivated Behavior: Dynamic Changes across Childhood and Adolescence.

The ability to anticipate and respond appropriately to the challenges and opportunities present in our environments is critical for adaptive behavior. Recent methodological innovations have led to substantial advances in our understanding of the neurocircuitry supporting such motivated behavior in adulthood. However, the neural circuits and cognitive processes that enable threat- and reward-motivated behavior undergo substantive changes over the course of development, and these changes are less well understood. In this article, we highlight recent research in human and animal models demonstrating how developmental changes in prefrontal-subcortical neural circuits give rise to corresponding changes in the processing of threats and rewards from infancy to adulthood. We discuss how these developmental trajectories are altered by experiential factors, such as early-life stress, and highlight the relevance of this research for understanding the developmental onset and treatment of psychiatric disorders characterized by dysregulation of motivated behavior.

Time ambiguity during intertemporal decision-making is aversive, impacting choice and neural value coding.

We are often presented with choices that differ in their more immediate versus future consequences. Interestingly, in everyday-life, ambiguity about the exact timing of such consequences frequently occurs, yet it remains unknown whether and how time-ambiguity influences decisions and their underlying neural correlates. We developed a novel intertemporal fMRI choice task in which participants make choices between sooner-smaller (SS) versus later-larger (LL) monetary rewards with systematically varying levels of time-ambiguity. Across trials, delay information of the SS, the LL, or both rewards was either exact (e.g., in 5 weeks), of low ambiguity (4 week range: e.g., in 3-7 weeks), or of high ambiguity (8 week range: e.g., in 1-9 weeks). Choice behavior showed that the majority of participants preferred options with exact delays over those with ambiguous delays, indicating time-ambiguity aversion. Consistent with these results, the ventromedial prefrontal cortex showed decreased activation during ambiguous versus exact trials. In contrast, intraparietal sulcus activation increased during ambiguous versus exact trials. Furthermore, exploratory analyses suggest that more time-ambiguity averse participants show more insula and dorsolateral prefrontal cortex activation during subjective value (SV)-coding of ambiguous versus exact trials. Lastly, the best-fitting computational choice models indicate that ambiguity impacts the SV of options via time perception or via an additive ambiguity-related penalty term. Together, these results provide the first behavioral and neural signatures of time-ambiguity, pointing towards a unique profile that is distinct from impatience. Since time-ambiguity is ubiquitous in real-life, it likely contributes to shortsighted decisions above and beyond delay-discounting.

The computational basis of following advice in adolescents.

Advice taking helps one to quickly acquire knowledge and make decisions. This age-comparative study (in children [8- to 10-year-olds], adolescents [13- to 15-year-olds], and adults [18- to 22-year-olds]) investigated developmental differences in how advice, experience, and exploration influence learning. The results showed that adolescents were initially easily swayed to follow peer advice but also switched more rapidly to exploring alternatives like children. Whereas adults stayed with the advice over the task, adolescents put more weight on their own experience compared with adults. A social learning model showed that although social influence most strongly affects adolescents' initial expectations (i.e., their priors), adolescents showed higher exploration and discovered the other good option in the current task. Thus, our model resolved the apparently conflicting findings of adolescents being more and less sensitive to peer influence and provides novel insights into the dynamic interaction between social and individual learning.

Adolescent impatience decreases with increased frontostriatal connectivity.

Adolescence is a developmental period associated with an increase in impulsivity. Impulsivity is a multidimensional construct, and in this study we focus on one of the underlying components: impatience. Impatience can result from (i) disregard of future outcomes and/or (ii) oversensitivity to immediate rewards, but it is not known which of these evaluative processes underlie developmental changes. To distinguish between these two causes, we investigated developmental changes in the structural and functional connectivity of different frontostriatal tracts. We report that adolescents were more impatient on an intertemporal choice task and reported less future orientation, but not more present hedonism, than young adults. Developmental increases in structural connectivity strength in the right dorsolateral prefrontal tract were related to increased negative functional coupling with the striatum and an age-related decrease in discount rates. Our results suggest that mainly increased control, and the integration of future-oriented thought, drives the reduction in impatience across adolescence.

Neural mechanisms of individual differences in temporal discounting of monetary and primary rewards in adolescents.

Adolescents are generally characterized as impulsive. However, impulsivity is a multi-dimensional construct that involves multiple component processes. Which of these components contribute to adolescent impulsivity is currently unclear. This study focused on the neural mechanisms underlying individual differences in distinct components of temporal discounting (TD), i.e., the preference for smaller immediate rewards over larger delayed rewards. Participants were 58 adolescents (12-16 years-old) who performed an fMRI TD task with both monetary and snack rewards. Using mixed-effects modeling, we determined participants' average impatience, and further decomposed TD choices into: 1) amount sensitivity (unique contribution of the magnitude of the immediate reward); and 2) delay sensitivity (unique contribution of delay duration). Adolescents' average impatience was positively correlated with frontoparietal and ventral striatal activity during delayed reward choices, and with ventromedial prefrontal cortex activity during immediate reward choices. Adolescents' amount sensitivity was positively associated with ventral striatal and dorsal anterior cingulate cortex activity during immediate reward choices. Delay sensitivity was positively correlated with inferior parietal cortex activity during delayed reward choices. As expected, snacks were discounted more steeply than money, and TD of both reward types was associated with overlapping activation in the inferior parietal cortex. Exploring whether testosterone or estradiol were associated with TD and its neural correlates revealed no significant associations. These findings indicate that distinct components contribute uniquely to TD choice and that individual differences in amount sensitivity are uniquely associated with activation of reward valuation areas, while individual differences in delay sensitivity are uniquely associated with activation of cognitive control areas.

Individual differences in social desirability are associated with white-matter microstructure of the external capsule.

Humans tend to present themselves in a positive light to gain social approval. This behavioral trait, termed social desirability, is important for various types of social success. Surprisingly, investigation into the neural underpinnings of social desirability has been limited and focused only on interindividual differences in dopamine receptor binding. These studies revealed reduced dopamine receptor binding in the striatum of individuals who are high in trait social desirability. Interestingly, high dopamine signaling has been associated with low white-matter integrity, irrespective of social desirability. Based on these findings, we hypothesized that a positive association exists between trait social desirability and the white-matter microstructure of the external capsule, which carries fibers to the striatum from the prefrontal cortex. To test this hypothesis, we collected diffusion tensor imaging data and examined the relationship between fractional anisotropy of the external capsule and participants' social desirability-our analysis revealed a positive association. As a second exploratory step, we examined the association between social desirability and white-matter microstructure throughout the whole brain. Our whole-brain analysis revealed associations within multiple major white-matter tracts, demonstrating that socially desirable behavior relies on connectivity between distributed brain regions.

Early adversity and learning: implications for typical and atypical behavioral development.

BACKGROUND: Children who experience early adversity often develop emotion regulatory problems, but little is known about the mechanisms that mediate this relation. We tested whether general associative learning processes contribute to associations between adversity, in the form of child maltreatment, and negative behavioral outcomes. METHODS: Eighty-one participants between 12 and 17 years of age were recruited for this study and completed a probabilistic learning Task. Forty-one of these participants had been exposed to physical abuse, a form of early adversity. Forty additional participants without any known history of maltreatment served as a comparison group. All participants (and their parents) also completed portions of the Youth Life Stress Interview to understand adolescent's behavior. We calculated measures of associative learning, and also constructed mathematical models of learning. RESULTS: We found that adolescents exposed to high levels of adversity early in their lives had lower levels of associative learning than comparison adolescents. In addition, we found that impaired associative learning partially explained the higher levels of behavioral problems among youth who suffered early adversity. Using mathematical models, we also found that two components of learning were specifically affected in children exposed to adversity: choice variability and biases in their beliefs about the likelihood of rewards in the environment. CONCLUSIONS: Participants who had been exposed to early adversity were less able than their peers to correctly learn which stimuli were likely to result in reward, even after repeated feedback. These individuals also used information about known rewards in their environments less often. In addition, individuals exposed to adversity made decisions early in the learning process as if rewards were less consistent and occurred more at random. These data suggest one mechanism through which early life experience shapes behavioral development.

Connectivity strength of dissociable striatal tracts predict individual differences in temporal discounting.

Large individual differences exist in the ability to delay gratification for the sake of satisfying longer-term goals. These individual differences are commonly assayed by studying intertemporal preferences, as revealed by choices between immediate and delayed rewards. In the brain, reward-based and goal-oriented decisions are believed to rely on the striatum and its interactions with other cortical and subcortical networks. However, it remains unknown which specific cortical-striatal tracts are involved in intertemporal decision making. We use connectivity analyses in both structural and functional MRI to further our understanding of the relationship between distinct corticostriatal networks and intertemporal preferences in humans. Our results revealed distinct striatal pathways that are differentially related to delay discounting. Structural and functional connectivity between striatum and lateral prefrontal cortex was associated with increased patience, whereas connectivity between subcortical areas and striatum was associated with increased impulsivity. These findings provide novel insights into how the anatomy and functioning of striatal circuits mediate individual differences in intertemporal choice.

Neural correlates of reinforcement learning and social preferences in competitive bidding.

In competitive social environments, people often deviate from what rational choice theory prescribes, resulting in losses or suboptimal monetary gains. We investigate how competition affects learning and decision-making in a common value auction task. During the experiment, groups of five human participants were simultaneously scanned using MRI while playing the auction task. We first demonstrate that bidding is well characterized by reinforcement learning with biased reward representations dependent on social preferences. Indicative of reinforcement learning, we found that estimated trial-by-trial prediction errors correlated with activity in the striatum and ventromedial prefrontal cortex. Additionally, we found that individual differences in social preferences were related to activity in the temporal-parietal junction and anterior insula. Connectivity analyses suggest that monetary and social value signals are integrated in the ventromedial prefrontal cortex and striatum. Based on these results, we argue for a novel mechanistic account for the integration of reinforcement history and social preferences in competitive decision-making.

Striatum-medial prefrontal cortex connectivity predicts developmental changes in reinforcement learning.

During development, children improve in learning from feedback to adapt their behavior. However, it is still unclear which neural mechanisms might underlie these developmental changes. In the current study, we used a reinforcement learning model to investigate neurodevelopmental changes in the representation and processing of learning signals. Sixty-seven healthy volunteers between ages 8 and 22 (children: 8-11 years, adolescents: 13-16 years, and adults: 18-22 years) performed a probabilistic learning task while in a magnetic resonance imaging scanner. The behavioral data demonstrated age differences in learning parameters with a stronger impact of negative feedback on expected value in children. Imaging data revealed that the neural representation of prediction errors was similar across age groups, but functional connectivity between the ventral striatum and the medial prefrontal cortex changed as a function of age. Furthermore, the connectivity strength predicted the tendency to alter expectations after receiving negative feedback. These findings suggest that the underlying mechanisms of developmental changes in learning are not related to differences in the neural representation of learning signals per se but rather in how learning signals are used to guide behavior and expectations.

Adolescents seek social information under uncertainty.

Adolescence is a period of emerging independence, in which adolescents face difficult decisions, including those that involve risk for health and well-being. Previous research suggests that learning from others might be a prominent strategy of adolescents to inform these difficult decisions. However, there is a gap in the literature that addresses the active role adolescents may have in gaining information about others' behavior (i.e., social information search). Here, we investigated when and how much social information adolescents search before making decisions under risk and ambiguity, using a novel social search paradigm. In this paradigm, adolescents were able to reveal real information about their classmates' choices before deciding on their final choice. Our two experiments suggest that social information search can be broken down in two independent decisions: first the decision to initiate search, followed by the decision to continue search. Several factors motivated initiation of search, including: (a) the difficulty of the choice, (b) uncertainty about the outcome, and (c) the magnitude of the reward at stake. Search took generally longer when adolescents faced information not in line with their initial preference. Finally, we observed that adolescents used the sampled social information to inform their risky-choice behavior. Taken together, these results provide novel insights into the dynamics of peer influence in adolescence and stress the importance of treating adolescents not only as receivers, but as active agents searching for social information. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Network distance and centrality shape social learning in the classroom.

Social learning can help individuals to efficiently acquire knowledge and skills. In the classroom, social learning often takes place in structured settings in which peers help, support, and tutor each other. Several protocols have been developed to make peer-assisted learning (PAL) more efficient. However, little attention has been devoted to how the transfer of knowledge is shaped by the social relationship between peers, and their relative positions in the social network. To address this gap, we combined social network analysis with an experimental social learning task, in which pupils (N = 135; aged 11-19) could use social information from their peers to improve their performance. We show that pupils' tendencies to use social information substantially decrease with the peer's distance in the social network. This effect is mediated by subjective closeness: pupils report feeling much closer to their friends than to their non-friends, and closeness strongly enhances social learning. Our results further show that, above and beyond these effects of network distance, social information use increases with the peer's social status (network centrality) and perceived smartness. Our results provide empirical evidence in a naturalistic setting for the role of specific network attributes in shaping pupils' willingness to learn from their peers. These findings illustrate the value of a social network approach for understanding knowledge transfer in the classroom and can be used to structure more effective peer learning. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Identifying who adolescents prefer as source of information within their social network.

Adolescents are highly influenced by their peers within their social networks. This social influence can stem from both unsolicited peer pressure and the active search for guidance. While extensive research examined the mechanisms of peer pressure, little is known about who adolescents prefer as a source of information. To address this gap, we conducted two independent studies using a novel social search paradigm that allows participants to choose which social sources they wish to observe. In both studies, adolescents demonstrated a preference for their friends over non-friends, as well as for peers who were perceived as trustworthy. Across both studies, we found mixed evidence for the role of perceived popularity as a selection criterion. Notable, study 2 revealed the significance of "cool", "admirable" and "acting mean" as additional characteristics of preferred peers, traits that are often associated with elevated peer status. It also revealed an interest for peers perceived as being smart. These findings highlight the active role adolescents have in choosing social sources and emphasize the importance of multiple peer characteristics. Future research should investigate whether adolescents' interest in these types of peers is contingent upon specific social contexts, age groups, and peer cultures.

Developmental changes in exploration resemble stochastic optimization.

Human development is often described as a 'cooling off' process, analogous to stochastic optimization algorithms that implement a gradual reduction in randomness over time. Yet there is ambiguity in how to interpret this analogy, due to a lack of concrete empirical comparisons. Using data from n = 281 participants ages 5 to 55, we show that cooling off does not only apply to the single dimension of randomness. Rather, human development resembles an optimization process of multiple learning parameters, for example, reward generalization, uncertainty-directed exploration and random temperature. Rapid changes in parameters occur during childhood, but these changes plateau and converge to efficient values in adulthood. We show that while the developmental trajectory of human parameters is strikingly similar to several stochastic optimization algorithms, there are important differences in convergence. None of the optimization algorithms tested were able to discover reliably better regions of the strategy space than adult participants on this task.