The human hypothalamus coordinates switching between different survival actions.

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.

Value-based neural representations predict social decision preferences.

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.

Model-based prioritization for acquiring protection.

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.

Frontopolar Cortex Response to Positive Feedback Relates to Nonincentivized Task Persistence.

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.

Physiological Responses to a Haunted-House Threat Experience: Distinct Tonic and Phasic Effects.

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.

Resting parasympathetic nervous system activity is associated with greater antiviral gene expression.

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.

Dichotomous thinking about social groups: Learning about one group can activate opposite beliefs about another group.

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.

Evidence from a Randomized Controlled Trial that Altruism Moderates the Effect of Prosocial Acts on Adolescent Well-being.

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.

Longitudinal Trajectories of Post-Election Distress Track Changes in Neural and Psychological Functioning.

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.

Neural recruitment related to threat perception differs as a function of adolescent sleep.

Detecting threat cues in the environment is an important aspect of social functioning. This is particularly true for adolescents as social threats become more salient and they navigate increasingly complex relationships outside of the family. Sleep relates to socioemotional processing throughout development, but the neurobiological relevance of sleep for threat perceptions in adolescence remains unknown. In the present study, 46 human adolescents (aged 14-18 years; 26 female) made judgments while undergoing a brain scan about whether unfamiliar, affectively neutral, computer-generated faces were threatening. Prior to the scan, several indices of sleep were assessed nightly for two-weeks using actigraphy. Sleep duration and poor sleep quality (defined as less efficiency, more awakenings, longer awakenings), factors influenced by biological and psychosocial changes during adolescence, elicited distinct neural activation patterns. Sleep duration was positively associated with activation in visual and face processing regions (occipital cortex, occipital fusiform gyrus), and this activation was linked to increased threat detection during the threat perception task. Sleep quality was negatively related to dorsolateral prefrontal cortex activation, which moderated the relation between reaction time (RT) and exposure to faces. Findings suggest reduced threat perception for adolescents with shorter sleep durations and more impulsive responding (as evinced by less consistent RT) for adolescents experiencing worse quality sleep. This study identifies an association between sleep and neural functioning relevant for socioemotional decision making during adolescence, a time when these systems undergo significant development.

The Role of Mesolimbic Circuitry in Buffering Election-Related Distress.

The 2016 U.S. presidential election yielded distress among many individuals who identify with historically marginalized groups. We used functional magnetic resonance imaging and psychological measures to test the hypotheses that neural response to reward, probing the nucleus accumbens (NAcc) and medial prefrontal cortex (mPFC), and social support would ameliorate the effects of election distress among those who felt negatively affected by the result. Within 4 months of the 2016 U.S. presidential election, we tested human participants who felt affected by the election result (n = 40, Mage = 21.9 years, 28 female) and control participants (n = 20, Mage = 20.25 years, 12 female) who did not feel affected by the election result. Election-related distress significantly differed between the groups, and distress accounted for over half of the relationship between discrimination experiences and depression symptoms among affected individuals. NAcc activation, connectivity between the NAcc and mPFC, and family support moderated the associations between election distress and depression symptoms. Prior work has primarily investigated mesolimbic circuitry in reward and motivation contexts, but our findings extend the relevance of functioning in this circuitry to ameliorating psychological manifestations of acute distress after shifts in political climate. These findings highlight the psychological effects of this important historic event and identify neurobiological and social mechanisms associated with individual differences in response to election distress.SIGNIFICANCE STATEMENT The 2016 U.S. presidential election was psychologically distressing for many individuals. In this study, election-related distress was linked to depression symptomology for affected individuals but not control individuals. However, among individuals distressed by the election, those with greater neural response to reward and higher family support were protected against these depressive symptoms. Previous research has examined how neural response to reward after a discrete event ameliorates clinical symptoms. The current study extends this knowledge by demonstrating that both the brain and social support may play influential roles in dampening affective responses to ongoing and anticipated distress related to political climate. Leveraging this finding to enact interventions that dampen continuous distress, political or otherwise, is a promising endeavor for future research.

Multivoxel Pattern Analysis Reveals a Neural Phenotype for Trust Bias in Adolescents.

The extent to which individuals are inclined to judge unfamiliar others as trustworthy can have important implications for social functioning. Using multivariate pattern analysis, a neural phenotype of trust bias was identified in 48 human adolescents (ages 14-18 years, 26 female). Adolescents who exhibited more similar brain response to faces at the extremes of a trustworthy gradient were more likely to rate neutral faces as trustworthy. This relation between neural pattern representation and trust bias was evinced in the amygdala. Amygdala-insula connectivity dissimilarity to faces at the extremes of the trustworthy gradient was associated with greater trust bias to neutral faces, serving as a distinct circuit-level contributor to decision-making over and above of amygdala pattern similarity. These findings aid understanding of neural mechanisms contributing to individual differences in social evaluations of ambiguity.

Physical home environment is associated with prefrontal cortical thickness in adolescents.

Biologically embedded experiences alter developmental trajectories in ways that can influence health, learning, and/or behavior. These systematic differences in experiences may contribute to different biological outcomes as individuals grow and develop, including at the neural level. Previous studies of biologically embedded experiences on neurodevelopment have focused on large-scale institutional or economic factors (e.g. socioeconomic status [SES]) and psychosocial factors (e.g. caregiving behavior). Less attention has focused on how the quality of the immediate home settings, such as the physical home environment (PHYS), influences neurodevelopment. Moreover, no study has investigated these effects in adolescents, who undergo significant physical maturation and neurodevelopment that may influence how they respond to their physical environments. The goal of the current study was to examine whether PHYS quality is biologically embedded in the developing adolescent brain as evidenced by cognitive achievement and cortical development in 56 (48% female) healthy adolescents (14-18 years (M = 16.83 years, SD = 1.17). Using in-home assessments of the physical home environment, anatomical brain scans, and indices of academic achievement, we found that adolescents who have more physical problems in the home (e.g. structural hazards, crowding, excessive noise, poorly lit) have thinner prefrontal cortices, which was associated with lower levels of reading achievement, independent of SES and psychosocial factors. By conducting home visits to assess physical characteristics of adolescents' home, we highlight a typically overlooked aspect of the home environment that has relevance for adolescents' cognitive and brain development.

Neural response to prosocial scenes relates to subsequent giving behavior in adolescents: A pilot study.

Adolescence is characterized by extensive neural development and sensitivity to social context, both of which contribute to engaging in prosocial behaviors. Although it is established that prosocial behaviors are linked to positive outcomes in adulthood, little is known about the neural correlates of adolescents' prosociality. Identifying whether the brain is differentially responsive to varying types of social input may be important for fostering prosocial behavior. We report pilot results using new stimuli and an ecologically valid donation paradigm indicating (1) brain regions typically recruited during socioemotional processing evinced differential activation when adolescents evaluated prosocial compared with social or noninteractive scenes (N = 20, ages 13-17 years, MAge = 15.30 years), and (2) individual differences in temporoparietal junction recruitment when viewing others' prosocial behaviors were related to adolescents' own charitable giving. These novel findings have significant implications for understanding how the adolescent brain processes prosocial acts and for informing ways to support adolescents to engage in prosocial behaviors in their daily lives.

Parents Versus Peers: Assessing the Impact of Social Agents on Decision Making in Young Adults.

Young adulthood is a developmental phase when individuals must navigate a changing social milieu that involves considering how their decisions affect close others such as parents and peers. To date, no empirical work has directly evaluated how young adults weigh these relationships against one another. We conducted a preregistered experiment in which we pitted outcomes for parents against outcomes for friends. Participants ( N = 174, ages 18-30 years) played two runs of the Columbia Card Task-one in which gains benefited a parent and losses were incurred by a friend and another in which the opposite was true. We also tested whether age, relationship quality, and reward type earned for parents and friends (simulated vs. real) acted as moderating influences on parent-friend prioritization. Results showed that individuals were more likely to make decisions that benefited a parent at the expense of a friend. Relationship quality and reward type moderated this effect, whereas age did not.

When Your Kind Cannot Live Here: How Generic Language and Criminal Sanctions Shape Social Categorization.

Using generic language to describe groups (applying characteristics to entire categories) is ubiquitous and affects how children and adults categorize other people. Five-year-olds, 8-year-olds, and adults ( N = 190) learned about a novel social group that separated into two factions (citizens and noncitizens). Noncitizens were described in either generic or specific language. Later, the children and adults categorized individuals in two contexts: criminal (individuals labeled as noncitizens faced jail and deportation) and noncriminal (labeling had no consequences). Language genericity influenced decision making. Participants in the specific-language condition, but not those in the generic-language condition, reduced the rate at which they identified potential noncitizens when their judgments resulted in criminal penalties compared with when their judgments had no consequences. In addition, learning about noncitizens in specific language (vs. generic language) increased the amount of matching evidence participants needed to identify potential noncitizens (preponderance standard) and decreased participants' certainty in their judgments. Thus, generic language encourages children and adults to categorize individuals using a lower evidentiary standard regardless of negative consequences for presumed social-group membership.

"These Pretzels Are Making Me Thirsty": Older Children and Adults Struggle With Induced-State Episodic Foresight.

We explored children's and adults' ability to disengage from current physiological states when forecasting future desires. In Study 1, 8- to 13-year-olds and adults (N = 104) ate pretzels (to induce thirst) and then predicted and explained what they would want tomorrow, pretzels or water. Demonstrating life-span continuity, approximately 70% of participants, regardless of age, chose water and referenced current thirst as their rationale. Individual differences in working memory and undergraduate grade point average were positively related to performance on the pretzel task. In Study 2, we obtained baseline preferences from adults (N = 35) and confirmed that, prior to consuming pretzels, people do not anticipate wanting water more than pretzels the next day. Together, these findings indicate that both children and adults are tethered to the present when forecasting their future desires.

Sleep variability over a 2-week period is associated with restfulness and intrinsic limbic network connectivity in adolescents.

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.

Positive and negative emotion are associated with generalized transcriptional activation in immune cells.

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.