Childhood unpredictability and the development of exploration

High willingness-to-taste in UK children aged 4-7 years was driven by contextual facilitation, not intervention, in a randomized controlled trial of sensory food education

Many children would benefit from a diet richer in vegetables and fruit. Reluctance to taste new foods is widely recognized as a barrier to healthy dietary variety in children. 'Flavour School' is a programme of 'sensory food education', aiming to increase children's confidence and curiosity in exploring foods and flavours, especially vegetables and fruit. We report a pre-registered, cluster-randomised controlled trial to assess the outcomes of the Flavour School programme, in n = 160 children aged 4-7 years from 5 UK schools in London and Leeds. Children either received the Flavour School programme (experimental group n = 84) or no intervention (control group n = 76), in a two-level design with children clustered within school classes. Data collection consisted of video recorded behavioural observation during a tasting activity designed to resemble a Flavour School activity, conducted before and after the intervention. Linear regression models were used to fit relationships between independent variables and outcomes; Willingness-to-taste, Enjoyment (positive/negative facial expression), and Expressiveness (change in facial expression). Most children engaged readily in the tasting activity at baseline. At follow-up children engaged with the tasting activity even more readily (on average biting one more food sample), with no significant effect of the intervention. We interpret these findings to indicate that intra-individual tasting behavior in children is context-dependent. Our results suggest that the context of sensory food education activities facilitates openness to tasting across the normal range of individual traits. However, we find no evidence that receiving sensory food education makes a reluctant taster into a less reluctant taster; no 'curative' effect of the intervention was observed. Rather, even usually fussy/reluctant children were often willing to have a go at tasting in the conducive context of an exploratory activity. TRIAL REGISTRATION: ISRCTN: 40249947 Date assigned 17/03/2020 Last edited 24/10/2022 Version 1.2 Trial Acronym OASES (Outcomes Assessment of Sensory Education in Schools).

Computational Mechanisms of Information-Seeking in Anxiety

The drive to seek information through exploratory behavior is widespread in both humans and other animals. This can be adaptive in reducing uncertainty about the best course of action within novel or changing environments. However, exploratory behaviors can also become maladaptive if subjective uncertainty levels remain too high or too low, as may happen in states of elevated anxiety. In this article, we review recent studies investigating the influence of anxiety on information-seeking behavior. We focus primarily on studies using cognitive computational models and associated behavioral tasks designed to test specific exploratory strategies, which could each be affected by anxiety in distinct ways. Results of current studies remain mixed and highlight the importance of distinguishing potential effects of task, state vs. trait anxiety, somatic vs. cognitive anxiety, and clinical vs. sub-clinical anxiety. There are also a range of different information-seeking strategies that are necessary to consider. At present, many findings could be taken to support a picture in which cognitive anxiety, and/or trait anxiety more broadly, may increase information-seeking, while somatic and/or state anxiety could have opposing effects. However, a number of previous results also appear inconsistent or task-dependent. Future studies are needed to resolve these apparent inconsistencies and more directly disentangle effects of different dimensions of anxiety on the adaptive and maladaptive use of information-seeking.

Finding order in chaos: influences of environmental complexity and predictability on development

Environments are dynamic and complex. Some children experience more predictable early life environments than others. Here, we consider how moment-by-moment complexity and predictability in our early environments influence development. New studies using wearable sensors are quantifying this environmental variability at a fine temporal resolution across hierarchically structured physical and social features. We identify three types of predictability: periodicities ('at X time intervals, Y happens'), stability ('given statex, statex+1 is known'), and contingency ('when I do X, Y happens'). We discuss how the temporal dynamics of environments may differ between individuals and the diverse developmental neural pathways through which this may influence outcomes, such as central nervous system (CNS) arousal and executive control. Finally, we discuss practical consequences and directions for future research.

Childhood maltreatment is associated with lower exploration and disrupted prefrontal activity and connectivity during reward learning in volatile environments

BACKGROUND

Atypical reward processing is implicated in a range of psychiatric disorders associated with childhood maltreatment and may represent a latent vulnerability mechanism. In this longitudinal study, we investigated the impact of maltreatment on behavioural and neural indices of reward learning in volatile environments and examined associations with future psychopathology assessed 18 months later.

METHODS

Thirty-seven children and adolescents with documented histories of maltreatment (MT group) and a carefully matched group of 32 non-maltreated individuals (NMT group) aged 10-16 were presented with a probabilistic reinforcement learning task featuring a phase of stable and a phase of volatile reward contingencies. Brain activation and connectivity were assessed simultaneously using functional magnetic resonance imaging (fMRI). Computational models were used to extract individual estimates of learning rates and temperature, and neural signals in prespecified regions of interest were analysed during volatile and stable environments. In regression analyses, behavioural measures and neural signals at baseline were used to predict psychological symptoms at follow-up.

RESULTS

The MT group showed lower behavioural exploration, which predicted decreased internalising symptoms at follow-up. The MT group had lower activation in the orbitofrontal cortex (OFC) during outcome delivery in volatile relative to stable contexts. OFC connectivity with an area in the mid-cingulate cortex was also lower during outcome processing, which predicted higher general psychopathology at follow-up.

CONCLUSIONS

These findings are consistent with the notion that low exploratory behaviour following childhood maltreatment is potentially a protective adaptation against internalising symptoms, while disrupted neural processing of reward learning in volatile environments may index latent vulnerability to mental illness.

The influence of anxiety on exploration: A review of computational modeling studies

Exploratory behaviors can serve an adaptive role within novel or changing environments. Namely, they facilitate information gain, allowing an organism to maintain accurate beliefs about the environment and select actions that better maximize reward. However, finding the optimal balance between exploration and reward-seeking behavior - the so-called explore-exploit dilemma - can be challenging, as it requires sensitivity to one's own uncertainty and to the predictability of one's surroundings. Given the close relationship between uncertainty and anxiety, a body of work has now also emerged identifying associated effects on exploration. In particular, the field of computational psychiatry has begun to use cognitive computational models to characterize how anxiety may modulate underlying information processing mechanisms, such as estimation of uncertainty and the value of information, and how this might contribute to psychopathology. Here, we review computational modeling studies investigating how exploration is influenced by anxiety. While some apparent inconsistencies remain to be resolved, studies using reinforcement learning tasks suggest that directed (but not random) forms of exploration may be elevated by trait and/or cognitive anxiety, but reduced by state and/or somatic anxiety. Anxiety is also consistently associated with less exploration in foraging tasks. Some differences in exploration may further stem from how anxiety modulates changes in uncertainty over time (learning rates). Jointly, these results highlight important directions for future work in refining choice of tasks and anxiety measures and maintaining consistent methodology across studies.

How adolescents learn to build social bonds: A developmental computational account of social explore-exploit decision-making

Building social bonds is a critical task of adolescence that affords opportunities for learning, identity formation, and social support. Failing to develop close relationships in adolescence hinders adult interpersonal functioning and contributes to problems such as loneliness and depression. During adolescence, increased reward sensitivity and greater social flexibility both contribute to healthy social development, yet we lack a clear theory of how these processes interact to support social functioning. Here, we propose synthesizing these two literatures using a computational reinforcement learning framework that recasts how adolescents pursue and learn from social rewards as a social explore-exploit problem. To become socially skilled, adolescents must balance both their efforts to form individual bonds within specific groups and manage memberships across multiple groups to maximize access to social resources. We draw on insights from sociological studies on social capital in collective networks and neurocognitive research on foraging and cooperation to describe the social explore-exploit dilemma faced by adolescents navigating a modern world with increasing access to diverse resources and group memberships. Our account provides important new directions for examining the dynamics of adolescent behavior in social groups and understanding how social value computations can support positive relationships into adulthood.

Leveraging the science of early life predictability to inform policies promoting child health

Addressing the tremendous burden of early-life adversity requires constructive dialogues between scientists and policy makers to improve population health. Whereas dialogues focused on several aspects of early-life adversity have been initiated, discussion of an underrecognized form of adversity that has been observed across multiple contexts and cultures is only now emerging. Here we provide evidence for "why unpredictability?", including: 1. Evidence that exposures to unpredictability affect child neurodevelopment, with influences that persist into adulthood. 2. The existence of a translational non-human animal model of exposure to early life unpredictability that can be capitalized upon to causally probe neurobiological mechanisms. 3. Evidence that patterns of signals in the early environment promote brain maturation across species. 4. The uneven distribution of unpredictability across demographic populations that illuminates a possible focal point for enhancing health equity. We then outline the potential of unpredictability in terms of the "what"; that is, how might the concept of unpredictability be leveraged to inform policy? We emphasize the importance of interdisciplinary and community partnerships to the success of this work and describe our community-engaged research project. Finally, we highlight opportunities for the science of unpredictability to inform policies in areas such as screening, immigration, criminal justice, education, childcare, child welfare, employment, healthcare and housing.

Sex-Specific Effects of Early Life Unpredictability on Hippocampal and Amygdala Responses to Novelty in Adolescents

Background

Unpredictable childhood experiences are an understudied form of early life adversity that impacts neurodevelopment in a sex-specific manner. The neurobiological processes by which exposure to early-life unpredictability impacts development and vulnerability to psychopathology remain poorly understood. The present study investigates the sex-specific consequences of early-life unpredictability on the limbic network, focusing on the hippocampus and the amygdala.

Methods

Participants included 150 youth (54% female). Early life unpredictability was assessed using the Questionnaire of Unpredictability in Childhood (QUIC). Participants engaged in a task-fMRI scan between the ages of 8 and 17 (223 total observations) measuring BOLD responses to novel and familiar scenes.

Results

Exposure to early-life unpredictability associated with BOLD contrast (novel vs. familiar) in a sex-specific manner. For males, but not females, higher QUIC scores were associated with lower BOLD activation in response to novel vs. familiar stimuli in the hippocampal head and amygdala. Secondary psychophysiological interaction (PPI) analyses revealed complementary sex-specific associations between QUIC and condition-specific functional connectivity between the right and left amygdala, as well as between the right amygdala and hippocampus bilaterally.

Conclusion

Exposure to unpredictability in early life has persistent implications for the functional operations of limbic circuits. Importantly, consistent with emerging experimental animal and human studies, the consequences of early life unpredictability differ for males and females. Further, impacts of early-life unpredictability were independent of other risk factors including lower household income and negative life events, indicating distinct consequences of early-life unpredictability over and above more commonly studied types of early life adversity.

The causal structure and computational value of narratives

Many human behavioral and brain imaging studies have used narratively structured stimuli (e.g., written, audio, or audiovisual stories) to better emulate real-world experience in the laboratory. However, narratives are a special class of real-world experience, largely defined by their causal connections across time. Much contemporary neuroscience research does not consider this key property. We review behavioral and neuroscientific work that speaks to how causal structure shapes comprehension of and memory for narratives. We further draw connections between this work and reinforcement learning, highlighting how narratives help link causes to outcomes in complex environments. By incorporating the plausibility of causal connections between classes of actions and outcomes, reinforcement learning models may become more ecologically valid, while simultaneously elucidating the value of narratives.

Individual longitudinal changes in DNA-methylome identify signatures of early-life adversity and correlate with later outcome

Adverse early-life experiences (ELA) affect a majority of the world's children. Whereas the enduring impact of ELA on cognitive and emotional health is established, there are no tools to predict vulnerability to ELA consequences in an individual child. Epigenetic markers including peripheral-cell DNA-methylation profiles may encode ELA and provide predictive outcome markers, yet the interindividual variance of the human genome and rapid changes in DNA methylation in childhood pose significant challenges. Hoping to mitigate these challenges we examined the relation of several ELA dimensions to DNA methylation changes and outcome using a within-subject longitudinal design and a high methylation-change threshold. DNA methylation was analyzed in buccal swab/saliva samples collected twice (neonatally and at 12 months) in 110 infants. We identified CpGs differentially methylated across time for each child and determined whether they associated with ELA indicators and executive function at age 5. We assessed sex differences and derived a sex-dependent 'impact score' based on sites that most contributed to methylation changes. Changes in methylation between two samples of an individual child reflected age-related trends and correlated with executive function years later. Among tested ELA dimensions and life factors including income to needs ratios, maternal sensitivity, body mass index and infant sex, unpredictability of parental and household signals was the strongest predictor of executive function. In girls, high early-life unpredictability interacted with methylation changes to presage executive function. Thus, longitudinal, within-subject changes in methylation profiles may provide a signature of ELA and a potential predictive marker of individual outcome.

Directed exploration is elevated in affective disorders but reduced by an aversive interoceptive state induction

Elevated anxiety and uncertainty avoidance are known to exacerbate maladaptive choice in individuals with affective disorders. However, the differential roles of state vs. trait anxiety remain unclear, and underlying computational mechanisms have not been thoroughly characterized. In the present study, we investigated how a somatic (interoceptive) state anxiety induction influences learning and decision-making under uncertainty in individuals with clinically significant levels of trait anxiety. A sample of 58 healthy comparisons (HCs) and 61 individuals with affective disorders (iADs; i.e., depression and/or anxiety) completed a previously validated explore-exploit decision task, with and without an added breathing resistance manipulation designed to induce state anxiety. Computational modeling revealed a pattern in which iADs showed greater information-seeking (i.e., directed exploration; Cohen's d=.39, p=.039) in resting conditions, but that this was reduced by the anxiety induction. The affective disorders group also showed slower learning rates across conditions (Cohen's d=.52, p=.003), suggesting more persistent uncertainty. These findings highlight a complex interplay between trait anxiety and state anxiety. Specifically, while elevated trait anxiety is associated with persistent uncertainty, acute somatic anxiety can paradoxically curtail exploratory behaviors, potentially reinforcing maladaptive decision-making patterns in affective disorders.

Strengthening through adversity: The hormesis model in developmental psychopathology

BACKGROUND

Employing a developmental psychopathology framework, we tested the utility of the hormesis model in examining the strengthening of children and youth through limited levels of adversity in relation to internalizing and externalizing outcomes within a brain-by-development context.

METHODS

Analyzing data from the Adolescent Brain and Cognitive Development study (N = 11,878), we formed latent factors of threat, deprivation, and unpredictability. We examined linear and nonlinear associations between adversity dimensions and youth psychopathology symptoms and how change of resting-state functional connectivity (rsFC) in the default mode network (DMN) from Time 1 to Time 5 moderates these associations.

RESULTS

A cubic association was found between threat and youth internalizing problems; low-to-moderate family conflict levels reduced these problems. Deprivation also displayed a cubic relation with youth externalizing problems, with moderate deprivation levels associated with fewer problems. Unpredictability linearly increased both problem types. Change in DMN rsFC significantly moderated the cubic link between threat levels and internalizing problems, with declining DMN rsFC levels from Time 1 to Time 5 facilitating hormesis. Hormetic effects peaked earlier, emphasizing the importance of sensitive periods and developmental timing of outcomes related to earlier experiences.

CONCLUSIONS

Strengthening through limited environmental adversity is crucial for developing human resilience. Understanding this process requires considering both linear and nonlinear adversity-psychopathology associations. Testing individual differences by brain and developmental context will inform preventive intervention programming.

Childhood unpredictability research within the developmental psychopathology framework: Advances, implications, and future directions

Greater unpredictability in childhood from the level of the caregiver-child dyad to broader family, home, or environmental instability is consistently associated with disruptions in cognitive, socioemotional, behavioral, and biological development in humans. These findings are bolstered by experimental research in non-human animal models suggesting that early life unpredictability is an important environmental signal to the developing organism that shapes neurodevelopment and behavior. Research on childhood unpredictability has surged in the past several years, guided in part by theoretical grounding from the developmental psychopathology framework (shaped largely by Dr. Dante Cicchetti's innovative work). The current review focuses on future directions for unpredictability research, including probing intergenerational effects, the role of predictability in resilience, cultural and contextual considerations, and novel developmental outcomes that should be tested in relation to childhood unpredictability. We urge the integration of multidisciplinary perspectives and collaborations into future research on unpredictability. We also provide ideas for translating this research to real-world practice and policy and encourage high-quality research testing whether incorporating predictability into interventions and policy improves developmental outcomes, which would support further dissemination of these findings.

Taking stock to move forward: Where the field of developmental psychopathology might be heading

In this paper, dedicated to Dante Cicchetti's contributions and enduring influence, we explore the prospective directions of developmental psychopathology. Our focus centers on key domains where Cicchetti's significant achievements have continually shaped our evolving thinking about psychological development. These domains include (a) the concepts of equifinality and multifinality, along with the challenges in predicting developmental trajectories, (b) the imperative to integrate wider sociocultural viewpoints into developmental psychopathology frameworks, (c) the interplay of genetic and environmental influences in developmental courses, (d) the significance of mental state language, and (e) the progress, or its absence, in the development of prevention and intervention tactics for children, adolescents, and their caregivers. While many of our forecasts regarding the future of developmental psychopathology may not materialize, we maintain optimistic that the essential ideas presented will influence the research agenda in this field and contribute to its growth over the next fifty years.