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1.
bioRxiv ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39091862

RESUMEN

Pivotal to self-preservation is the ability to identify when we are safe and when we are in danger. Previous studies have focused on safety estimations based on the features of external threats and do not consider how the brain integrates other key factors, including estimates about our ability to protect ourselves. Here we examine the neural systems underlying the online dynamic encoding of safety. The current preregistered study used two novel tasks to test four facets of safety estimation: Safety Prediction, Meta-representation, Recognition, and Value Updating. We experimentally manipulated safety estimation changing both levels of external threats and self-protection. Data were collected in two independent samples (behavioral N=100; fMRI N=30). We found consistent evidence of subjective changes in the sensitivity to safety conferred through protection. Neural responses in the ventromedial prefrontal cortex (vmPFC) tracked increases in safety during all safety estimation facets, with specific tuning to protection. Further, informational connectivity analyses revealed distinct hubs of safety coding in the posterior and anterior vmPFC for external threats and protection, respectively. These findings reveal a central role of the vmPFC for coding safety.

2.
PLoS Biol ; 22(6): e3002624, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38941452

RESUMEN

Comparative research suggests that the hypothalamus is critical in switching between survival behaviors, yet it is unclear if this is the case in humans. Here, we investigate the role of the human hypothalamus in survival switching by introducing a paradigm where volunteers switch between hunting and escape in response to encounters with a virtual predator or prey. Given the small size and low tissue contrast of the hypothalamus, we used deep learning-based segmentation to identify the individual-specific hypothalamus and its subnuclei as well as an imaging sequence optimized for hypothalamic signal acquisition. Across 2 experiments, we employed computational models with identical structures to explain internal movement generation processes associated with hunting and escaping. Despite the shared structure, the models exhibited significantly different parameter values where escaping or hunting were accurately decodable just by computing the parameters of internal movement generation processes. In experiment 2, multi-voxel pattern analyses (MVPA) showed that the hypothalamus, hippocampus, and periaqueductal gray encode switching of survival behaviors while not encoding simple motor switching outside of the survival context. Furthermore, multi-voxel connectivity analyses revealed a network including the hypothalamus as encoding survival switching and how the hypothalamus is connected to other regions in this network. Finally, model-based fMRI analyses showed that a strong hypothalamic multi-voxel pattern of switching is predictive of optimal behavioral coordination after switching, especially when this signal was synchronized with the multi-voxel pattern of switching in the amygdala. Our study is the first to identify the role of the human hypothalamus in switching between survival behaviors and action organization after switching.


Asunto(s)
Hipotálamo , Imagen por Resonancia Magnética , Humanos , Hipotálamo/fisiología , Imagen por Resonancia Magnética/métodos , Masculino , Adulto , Femenino , Adulto Joven , Hipocampo/fisiología , Reacción de Fuga/fisiología , Aprendizaje Profundo , Mapeo Encefálico/métodos , Sustancia Gris Periacueductal/fisiología
3.
Cereb Cortex ; 33(13): 8605-8619, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37183179

RESUMEN

Social decision-making is omnipresent in everyday life, carrying the potential for both positive and negative consequences for the decision-maker and those closest to them. While evidence suggests that decision-makers use value-based heuristics to guide choice behavior, very little is known about how decision-makers' representations of other agents influence social choice behavior. We used multivariate pattern expression analyses on fMRI data to understand how value-based processes shape neural representations of those affected by one's social decisions and whether value-based encoding is associated with social decision preferences. We found that stronger value-based encoding of a given close other (e.g. parent) relative to a second close other (e.g. friend) was associated with a greater propensity to favor the former during subsequent social decision-making. These results are the first to our knowledge to explicitly show that value-based processes affect decision behavior via representations of close others.


Asunto(s)
Toma de Decisiones , Conducta Social , Humanos , Amigos , Imagen por Resonancia Magnética
4.
Psychoneuroendocrinology ; 153: 106103, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37054596

RESUMEN

Alterations in immune system gene expression have been implicated in psychopathology, but it remains unclear whether similar associations occur for intraindividual variations in emotion. The present study examined whether positive emotion and negative emotion were related to expression of pro-inflammatory and antiviral genes in circulating leukocytes from a community sample of 90 adolescents (Mage = 16.3 years, SD = 0.7; 51.1% female). Adolescents reported their positive emotion and negative emotion and provided blood samples twice, five weeks apart. Using a multilevel analytic framework, we found that within-individual increases in positive emotion were associated with reduced expression of both pro-inflammatory and Type I interferon (IFN) response genes, even after adjusting for demographic and biological covariates, and for leukocyte subset abundance. By contrast, increases in negative emotion were related to higher expression of pro-inflammatory and Type I IFN genes. When tested in the same model, only associations with positive emotion emerged as significant, and increases in overall emotional valence were associated with both lower pro-inflammatory and antiviral gene expression. These results are distinct from the previously observed Conserved Transcriptional Response to Adversity (CTRA) gene regulation pattern characterized by reciprocal changes in pro-inflammatory and antiviral gene expression and may reflect alterations in generalized immunologic activation. These findings highlight one biological pathway by which emotion may potentially impact health and physiological function in the context of the immune system, and future studies can investigate whether fostering positive emotion may promote adolescent health through changes in the immune system.


Asunto(s)
Emociones , Transcriptoma , Adolescente , Humanos , Femenino , Masculino , Activación Transcripcional , Emociones/fisiología , Regulación de la Expresión Génica , Antivirales
5.
Sleep ; 46(2)2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36223429

RESUMEN

STUDY OBJECTIVES: Sleep duration and intraindividual variability in sleep duration undergo substantial changes in adolescence and impact brain and behavioral functioning. Although experimental work has linked acute sleep deprivation to heightened limbic responding and reduced regulatory control, there is limited understanding of how variability in sleep patterns might interact with sleep duration to influence adolescent functioning. This is important for optimal balancing of length and consistency of sleep. Here, we investigated how objective indices of sleep duration and variability relate to stress, restfulness, and intrinsic limbic network functioning in adolescents. METHODS: A sample of 101 adolescents ages 14-18 reported their stressors, after which they wore wrist actigraph watches to monitor their sleep and rated their restfulness every morning over a 2-week period. They also completed a resting-state fMRI scan. RESULTS: Adolescents reporting more stress experienced shorter sleep duration and greater sleep variability over the 2-week period. Longer nightly sleep duration was linked to feeling more rested the next morning, but this effect was reduced in adolescents with high cumulative sleep variability. Sleep variability showed both linear and quadratic effects on limbic connectivity: adolescents with high sleep variability exhibited more connectivity within the limbic network and less connectivity between the limbic and frontoparietal networks than their peers, effects which became stronger once variability exceeded an hour. CONCLUSIONS: Results suggest that cumulative sleep variability is related to stress and limbic network connectivity and shows interactive effects with sleep duration, highlighting the importance of balancing length and consistency of sleep for optimal functioning in adolescence.


Asunto(s)
Actigrafía , Sueño , Adolescente , Humanos , Actigrafía/métodos , Privación de Sueño , Descanso , Encéfalo
6.
PLoS Comput Biol ; 18(12): e1010805, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36534704

RESUMEN

Protection often involves the capacity to prospectively plan the actions needed to mitigate harm. The computational architecture of decisions involving protection remains unclear, as well as whether these decisions differ from other beneficial prospective actions such as reward acquisition. Here we compare protection acquisition to reward acquisition and punishment avoidance to examine overlapping and distinct features across the three action types. Protection acquisition is positively valenced similar to reward. For both protection and reward, the more the actor gains, the more benefit. However, reward and protection occur in different contexts, with protection existing in aversive contexts. Punishment avoidance also occurs in aversive contexts, but differs from protection because punishment is negatively valenced and motivates avoidance. Across three independent studies (Total N = 600) we applied computational modeling to examine model-based reinforcement learning for protection, reward, and punishment in humans. Decisions motivated by acquiring protection evoked a higher degree of model-based control than acquiring reward or avoiding punishment, with no significant differences in learning rate. The context-valence asymmetry characteristic of protection increased deployment of flexible decision strategies, suggesting model-based control depends on the context in which outcomes are encountered as well as the valence of the outcome.


Asunto(s)
Aprendizaje , Refuerzo en Psicología , Humanos , Estudios Prospectivos , Aprendizaje/fisiología , Recompensa , Castigo
8.
Psychol Sci ; 33(2): 236-248, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35001710

RESUMEN

Threats elicit physiological responses, the frequency and intensity of which have implications for survival. Ethical and practical limitations on human laboratory manipulations present barriers to studying immersive threat. Furthermore, few investigations have examined group effects and concordance with subjective emotional experiences to threat. The current preregistered study measured electrodermal activity in 156 adults while they participated in small groups in a 30-min haunted-house experience involving various immersive threats. Results revealed positive associations between (a) friends and tonic arousal, (b) unexpected attacks and phasic activity (frequency and amplitude), (c) subjective fear and phasic frequency, and (d) dissociable sensitization effects linked to baseline orienting response. Findings demonstrate the relevance of (a) social dynamics (friends vs. strangers) for tonic arousal and (b) subjective fear and threat predictability for phasic arousal.


Asunto(s)
Nivel de Alerta , Respuesta Galvánica de la Piel , Adulto , Nivel de Alerta/fisiología , Emociones , Miedo/fisiología , Humanos
9.
Cereb Cortex ; 32(11): 2293-2309, 2022 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-34581407

RESUMEN

When individuals make decisions whether to persist at a task, their decision-making is informed by whether success is pending or accomplished. If pending, the brain facilitates behavioral persistence; if the goal is accomplished or no longer desired, the brain enables switching away from the current task. Feedback, which is known to differentially engage reward neurocircuitry, may modulate goal-directed behavior such as task persistence. However, prior studies are confounded by offering external incentives for persistence. This study tested whether neural response to feedback differed as a function of nonincentivized task persistence in 99 human participants ages 13-30 (60 females). Individuals who persisted engaged the frontopolar cortex (FPC) to a greater extent during receipt of task-relevant positive feedback compared with negative feedback. For individuals who quit, task-irrelevant monetary reward engaged the FPC to a greater extent compared with positive feedback. FPC activation in response to positive feedback is identified as a key contributor to task persistence.


Asunto(s)
Mapeo Encefálico , Recompensa , Adolescente , Adulto , Atención , Encéfalo/fisiología , Retroalimentación , Femenino , Humanos , Adulto Joven
10.
Brain Behav Immun ; 98: 310-316, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34461235

RESUMEN

Parasympathetic nervous system activity can downregulate inflammation, but it remains unclear how parasympathetic nervous system activity relates to antiviral activity. The present study examined associations between parasympathetic nervous system activity and cellular antiviral gene regulation in 90 adolescents (Mage = 16.28, SD = 0.73; 51.1% female) who provided blood samples and measures of cardiac respiratory sinus arrhythmia (RSA), twice, five weeks apart. Using a multilevel analytic framework, we found that higher RSA (an indicator of higher parasympathetic nervous system activity)-both at rest and during paced breathing-was associated with higher expression of Type I interferon (IFN) response genes in circulating leukocytes, even after adjusting for demographic and biological covariates. RSA was not associated with a parallel measure of inflammatory gene expression. These results identify a previously unrecognized immunoregulatory aspect of autonomic nervous system function and highlight a potential biological pathway by which parasympathetic nervous system activity may relate to health.


Asunto(s)
Antivirales , Sistema Nervioso Simpático , Adolescente , Femenino , Expresión Génica , Frecuencia Cardíaca , Humanos , Masculino , Sistema Nervioso Parasimpático
11.
Cogn Psychol ; 129: 101408, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34330016

RESUMEN

Across three studies (N = 607), we examined people's use of a dichotomizing heuristic-the inference that characteristics belonging to one group do not apply to another group-when making judgments about novel social groups. Participants learned information about one group (e.g., "Zuttles like apples"), and then made inferences about another group (e.g., "Do Twiggums like apples or hate apples?"). Study 1 acted as a proof of concept: Eight-year-olds and adults (but not 5-year-olds) assumed that the two groups would have opposite characteristics. Learning about the group as a generic whole versus as specific individuals boosted the use of the heuristic. Study 2 and Study 3 (sample sizes, methods, and analyses pre-registered), examined whether the presence or absence of several factors affected the activation and scope of the dichotomizing heuristic in adults. Whereas learning about or treating the groups as separate was necessary for activating dichotomous thinking, intergroup conflict and featuring only two (versus many) groups was not required. Moreover, the heuristic occurred when participants made both binary and scaled decisions. Once triggered, adults applied this cognitive shortcut widely-not only to benign (e.g., liking apples) and novel characteristics (e.g., liking modies), but also to evaluative traits signaling the morals or virtues of a social group (e.g., meanness or intelligence). Adults did not, however, extend the heuristic to the edges of improbability: They failed to dichotomize when doing so would attribute highly unusual preferences (e.g., disliking having fun). Taken together, these studies indicate the presence of a dichotomizing heuristic with broad implications for how people make social group inferences.


Asunto(s)
Juicio , Aprendizaje , Adulto , Preescolar , Emociones , Heurística , Humanos , Inteligencia
13.
Trends Cogn Sci ; 25(5): 342-354, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674206

RESUMEN

Accurately estimating safety is critical to pursuing nondefensive survival behaviors. However, little attention has been paid to how the human brain computes safety. We conceptualize a model that consists of two components: (i) threat-oriented evaluations that focus on threat value, imminence, and predictability; and (ii) self-oriented evaluations that focus on the agent's experience, strategies, and ability to control the situation. Our model points to the dynamic interaction between these two components as a mechanism of safety estimation. Based on a growing body of human literature, we hypothesize that distinct regions of the ventromedial prefrontal cortex (vmPFC) respond to threat and safety to facilitate survival decisions. We suggest safety is not an inverse of danger, but reflects independent computations that mediate defensive circuits and behaviors.


Asunto(s)
Imagen por Resonancia Magnética , Corteza Prefrontal , Encéfalo , Mapeo Encefálico , Humanos
14.
J Exp Soc Psychol ; 932021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35291212

RESUMEN

Every day, human beings make decisions with social consequences. These social consequences matter most when they impact those closest to us. Recent research has shown that humans exhibit reliable preferences when deciding between conflicting outcomes involving close others - for example, prioritizing the interests of one's family member over one's friend. However, virtually nothing is known about the mechanisms that drive these preferences. We conducted a pre-registered study in a large (maximum N=375) sample to quantify the computational and motivational mechanisms of human social decision-making preferences involving close others. By pairing assessment techniques from behavioral economics and psychological science with computational modeling and random coefficient regression, we show that value-based cognitive computations (e.g., risk and loss aversion) drive social decision-making preferences involving financial outcomes, whereas socioemotional motivations (e.g., relationship quality) underlie preferences involving social outcomes. These results imply mechanistic heterogeneity, underscoring a need for greater attention to contextual specificity in social decision-making.

15.
J Youth Adolesc ; 50(1): 29-43, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33278014

RESUMEN

Despite growing public and scientific interest in the positive benefits of prosociality, there has been little research on the causal effects of performing kind acts for others on psychological well-being during adolescence. Developmental changes during adolescence, such as greater perspective taking, can promote prosociality. It was hypothesized that performing kind acts for others would improve adolescent well-being (positive and negative affect, perceived stress) and increase prosocial giving. As part of a randomized controlled trial, 97 adolescents (Mage = 16.224, SD = 0.816, range 14-17; 53.608% female) were assigned to either perform kind acts for others (Kindness to Others, N = 33), perform kind acts for themselves (Kindness to Self, N = 34), or report on daily activities (Daily Report, N = 30) three times per week for four weeks. Well-being factors were measured weekly and giving was tested post-intervention. Overall, changes over time in well-being did not differ across conditions. However, altruism emerged as a significant moderator such that altruistic adolescents in the Kindness to Others condition showed increased positive affect, decreased negative affect, and decreased stress. Increased positive affect was also linked to greater prosocial giving for Kindness to Others adolescents. These findings identify individual differences that may shape the effects of doing kind acts for others on well-being during adolescence.


Asunto(s)
Salud del Adolescente , Altruismo , Adolescente , Femenino , Humanos , Lactante , Masculino , Conducta Social
16.
J Interpers Violence ; 36(13-14): NP7388-NP7414, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-30735095

RESUMEN

Once social services steps in to protect children from violence and neglect in their homes, many youth become wards of the specialized juvenile or family court that assists in child protection (e.g., the dependency court). Some of these children will be ordered into foster care. Within this "dependency system," such children often feel a lack of voice. This study tests the prediction that foster youth who perceive having more opportunity for voice, even indirectly via a representative, more favorably rate the dependency system. Adolescents (n = 110), aged 17 years, involved in foster care and age-matched nonfoster youth rated "how good or bad the foster care/dependency court is for foster youth." The foster youth were also asked about their interactions with the court and with their attorney representatives. Foster and nonfoster youth did not significantly differ in dependency system ratings when considered at the overall group level. However, foster and nonfoster youth ratings significantly differed when foster youth's views of relevant prior legal experiences (e.g., frequency of child-attorney contact, quality of attorney representation) were taken into account: Youth with the highest perceived quality of experiences indicated more positive views than any other group. The importance of perceived quality of experience adds insight into mechanisms for improving adolescents' feelings of voice in the legal system.


Asunto(s)
Maltrato a los Niños , Cuidados en el Hogar de Adopción , Adolescente , Niño , Familia , Humanos , Abogados , Violencia
17.
Soc Cogn Affect Neurosci ; 15(7): 775-787, 2020 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-32756878

RESUMEN

Cognitive performance can become impaired when a stimulus evokes an emotional response. Social media often elicits emotional reactions, but, despite social media's ubiquity, cognitive and neural consequences of exposure to negative online content are relatively unknown. Fifty-seven human adults (18-29 years; 38 female) who identified with at least one historically-marginalized group performed a novel 'Tweet Task'. While undergoing functional magnetic resonance imaging, participants completed a spatial reasoning task before and after reading a set of actual tweets. Participants were randomly assigned to read negative, discriminatory tweets from President Trump (Negative Condition) or neutral tweets (Neutral Condition). Participants in the Negative Condition reported worsening affect and demonstrated performance interference post-tweet compared to those in the Neutral Condition. Affect post-tweet was associated with parametric reductions in left dorsolateral prefrontal cortex, which predicted variance in performance beyond elicited negative affect. Performance effects were demonstrated on an unrelated spatial reasoning task suggesting that engaging with negative, emotionally-arousing content on social media can have deleterious effects on executive functioning in non-social domains.


Asunto(s)
Emociones/fisiología , Función Ejecutiva/fisiología , Corteza Prefrontal/diagnóstico por imagen , Medios de Comunicación Sociales , Adolescente , Adulto , Cognición/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
18.
Dev Cogn Neurosci ; 43: 100790, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32510345

RESUMEN

The biological, environmental, and psychosocial changes that occur in adolescence engender an increase in risk taking often linked to the high rates of motor vehicle crashes amongst young drivers. Most U.S. adolescents suffer from poor sleep, which is known to exacerbate the risk of driving crashes; however, research has yet to uncover a neurobiological link between sleep and risky driving in adolescence. Here, we examined potential moderators of the sleep-risk relation in fifty-six adolescents (14-18y/o) as they completed a driving task during fMRI. While poor sleep was associated with increased risky driving (i.e., running more yellow lights), good sleep emerged as a novel buffer against risky driving in lower sensation-seeking adolescents. Neural activity in the ventral striatum (VS), a key node of the risk-taking circuit, also moderated the sleep-risk association: sleep was related to risk-taking in individuals demonstrating high, but not low, VS response during risky decision-making, suggesting that reward-related neural response may underly the connection between sleep and risk-taking in adolescence. This study sheds light on the risk of driving crashes in youth by highlighting sleep as both an exacerbator and a buffer of risky driving in adolescence. Taken together, these results underscore the importance of improving adolescent sleep.


Asunto(s)
Conducta del Adolescente/fisiología , Conducción de Automóvil/psicología , Asunción de Riesgos , Sueño/fisiología , Adolescente , Femenino , Humanos , Masculino
19.
J Cogn Neurosci ; 32(6): 1198-1210, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32013683

RESUMEN

The shift in political climate after the 2016 U.S. presidential election had a distressing effect on many individuals. To date, no research has identified how changes in societal-level distressing experiences affected ongoing neurobiological and psychological functioning. Fifty-five participants (Mage = 21.746, 37 women) were tested at two time points. fMRI and psychological measures were used to test the hypotheses that increases in distress over 1 year would relate to worsening mental health symptomology and blunted neurobiological response to reward during the same period. Because individual experiences of distress occurred within a larger macroclimate of societal attitudes, measures were standardized to reflect relative change within the sample. Distress changes over 1 year were positively associated with problematic mental health symptomology and nucleus accumbens (NAcc) response to reward, with dissociable effects for anticipation and outcome. Worsening distress was associated with increased NAcc response to reward anticipation but decreased NAcc response to reward outcome. Individuals who exhibited increased sensitivity to anticipatory reward were those who exhibited more avoidance distress symptoms, whereas intrusion and hyperarousal were associated with decreased sensitivity to reward outcome. This study highlights the importance of considering individual variation in profiles of change in response to ongoing distress, suggests that individual response styles yield differences in reward sensitivity, and extends neurobiological understanding of exposure to stressful life experiences to political events.


Asunto(s)
Anticipación Psicológica/fisiología , Núcleo Accumbens/fisiopatología , Política , Distrés Psicológico , Recompensa , Estrés Psicológico/fisiopatología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Individualidad , Imagen por Resonancia Magnética , Masculino , Núcleo Accumbens/diagnóstico por imagen , Estrés Psicológico/diagnóstico por imagen , Adulto Joven
20.
J Exp Psychol Gen ; 149(8): 1509-1526, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31804124

RESUMEN

Humans make decisions across a variety of social contexts. Though social decision-making research has blossomed in recent decades, surprisingly little is known about whether social decision-making preferences are consistent across different domains. We conducted an exploratory study in which participants made choices about 2 types of close others: parents and friends. To elicit decision making preferences, we pit the interests in parents and friends against one another. To assess the consistency of preferences for close others, decision making was assessed in three domains-risk taking, probabilistic learning, and self-other similarity judgments. We reasoned that if social decision-making preferences are consistent across domains, participants ought to exhibit the same preference in all three domains (i.e., a parent preference, based on prior work), and individual differences in preference magnitude ought to be conserved across domains within individuals. A combination of computational modeling, random coefficient regression, and traditional statistical tests revealed a robust parent-over-friend preference in the risk taking and probabilistic learning domains but not the self-other similarity domain. Preferences for parent-over-friend in the risk-taking domain were strongly associated with similar preferences in the probabilistic learning domain but not the self-other similarity domain. These results suggest that distinct and dissociable value-based and social-cognitive computations underlie social decision making. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Toma de Decisiones/fisiología , Juicio/fisiología , Aprendizaje por Probabilidad , Asunción de Riesgos , Conducta Social , Adulto , Femenino , Amigos , Humanos , Masculino , Padres , Adulto Joven
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