Dimensional models of early life adversity highlight the distinct roles of deprivation and threat in shaping neurocognitive development and mental health. However, relatively little is known about the role of unpredictability within each dimension. We estimated both the average levels of, and the temporal unpredictability of deprivation and threat exposure during adolescence in a high-risk, longitudinal sample of 1354 youth (Pathways to Desistance study). We then related these estimates to later life psychological distress, and Antisocial and Borderline personality traits, and tested whether any effects are mediated by future orientation. High average levels of both deprivation and threat exposure were found to be associated with worse mental health on all three outcomes, but only the effects on Antisocial and Borderline personality traits were mediated by decreased future orientation, a pattern consistent with evolutionary models of psychopathology. Unpredictability in deprivation exposure proved to be associated with increased psychological distress and a higher number of Borderline traits, but with increased future orientation. There was some evidence of unpredictability in threat exposure buffering against the detrimental developmental effects of average threat levels. Our results suggest that the effects of unpredictability are distinct within different dimensions of early life adversity.

The idea that some abilities might be enhanced by adversity is gaining traction. Adaptation-based approaches have uncovered a few specific abilities enhanced by particular adversity exposures. Yet, for a field to grow, we must not dig too deep, too soon. In this paper, we complement confirmatory research with principled exploration. We draw on two insights from adaptation-based research: 1) enhanced performance manifests within individuals, and 2) reduced and enhanced performance can co-occur. Although commonly assumed, relative performance differences are rarely tested. To quantify them, we need a wide variety of ability measures. However, rather than using adaptive logic to predict which abilities are enhanced or reduced, we develop statistical criteria to identify three data patterns: reduced, enhanced, and intact performance. With these criteria, we analyzed data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development to investigate how adversity shapes within-person performance across 10 abilities in a cognitive and achievement battery. Our goals are to document adversity-shaped cognitive performance patterns, identify drivers of reduced performance, identify sets of “intact” abilities, and discover new enhanced abilities. We believe principled exploration with clear criteria can help break new theoretical and empirical ground, remap old territory, and advance theory development.

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.

There has been significant interest and progress in understanding the role of caregiver unpredictability on brain maturation, cognitive and socioemotional development, and psychopathology. Theoretical consensus has emerged about the unique influence of unpredictability in shaping children’s experience, distinct from other adverse exposures or features of stress exposure. Nonetheless, the field still lacks theoretical and empirical common ground due to difficulties in accurately conceptualizing and measuring unpredictability in the caregiver–child relationship. In this paper, we first provide an overview of the role of unpredictability in theories of caregiving and childhood adversity and present four issues that are currently under-discussed but are crucial to the field. Focusing on how moment-to-moment and day-to-day dynamics are at the heart of caregiver unpredictability, we review three approaches aiming to address some of these nuances: Environmental statistics, entropy, and dynamic systems. Lastly, we conclude with a broad summary and suggest future research directions. Systematic progress in this field can inform interventions and policies aiming to increase stability in the lives of children.

Stray voltage (< 10 V) may impair animal welfare. Our objectives were to: i) determine the threshold at which heifers react to voltage and ii) investigate effects of past experience and random applications of voltage. Firstly, forty heifers were trained to eat from two metallic feeders at the end of a test corridor. For 20 heifers, voltage was applied for 2 min (every day in steps of 0.33 V, 0 to 5 V) to the feeder (F1) in which the heifer started to eat (VOLT). Heifers could change to the non-electrified feeder (F2) if they wished. Twenty heifers (CONT) followed the same procedure without voltage exposure. For voltages≥ 2.3 V, percentage of feed eaten from F1 (%FeedF1) was lower, time spent eating in F1 and latency to change to F2 were shorter compared to 0 V. At 2 V and above, more VOLT than CONT heifers performed muzzle-licking and abrupt head movements. Secondly, after four weeks, the same heifers were exposed to 3.3 V for either 11 consecutive days (DAILY, n = 20) or randomly on 4/11 days (RAND, n = 20). CONT heifers had higher cortisol concentrations than VOLT heifers on the first day of test. %FeedF1 was higher for RAND than DAILY heifers. The threshold at which avoidance behaviour started appeared to be 2.3 V in our experimental conditions. Adaptation was more difficult with unpredictable rather than predictable voltage and past experience seemed to reduce the effects of subsequent exposure.

The environment has pervasive impacts on human development, and two key environmental conditions – harshness and unpredictability – are proposed to be instrumental in tuning development. This study examined (1) how harsh and unpredictable environments related to immune and clinical outcomes in the context of childhood asthma, and (2) whether there were independent associations of harshness and unpredictability with these outcomes. Participants were 290 youth physician-diagnosed with asthma. Harshness was assessed with youth-reported exposure to violence and neighborhood-level murder rate. Unpredictability was assessed with parent reports of family structural changes. Youth also completed measures of asthma control as well as asthma quality of life and provided blood samples to assess immune profiles, including in vitro cytokine responses to challenge and sensitivity to inhibitory signals from glucocorticoids. Results indicated that harshness was associated with more pronounced pro-inflammatory cytokine production following challenge and less sensitivity to the inhibitory properties of glucocorticoids. Furthermore, youth exposed to harsher environments reported less asthma control and poorer quality of life. All associations with harshness persisted when controlling for unpredictability. No associations between unpredictability and outcomes were found. These findings suggest that relative to unpredictability, harshness may be a more consistent correlate of asthma-relevant immune and clinical outcomes.

Differential susceptibility theory stipulates that individuals vary in their susceptibility to environmental effects, often implying that the same individuals differ in the same way in their susceptibility to different environmental exposures. The latter point is addressed herein by evaluating the extent to which early-life harshness and unpredictability affect mother's psychological well-being and parenting, as well as their adolescent's life-history strategy, as reflected in number of sexual partners by age 15 years, drawing on data from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development. Results indicated that mothers whose well-being and parenting proved more susceptible to harshness also proved somewhat more susceptible to environmental unpredictability, with the same being true of adolescent sexual behavior. Nevertheless, findings caution against overgeneralizing sample-level findings to all individuals.

Using a conditioned suppression task, we examined the minimal conditions to establish context conditioning as induced by unpredictability of an unconditioned stimulus (US). We investigated whether a biologically significant US is necessary to produce such context conditioning effects. In this between-subjects experiment, we manipulated the nature of the US and US-unpredictability. In the Paired condition, the conditioned stimulus (CS) was always followed by the US, whereas in the Unpaired condition, the CS and the US were presented explicitly unpaired, that is, the CS was never followed by the US. Half of the participants received an aversive, biologically significant human scream, and the other half received a more neutral, biologically non-significant sound as US. Results show more contextual suppression in the Unpaired condition than in the Paired condition. We conclude that in an expectancy-based conditioning task, US-unpredictability, but not a biologically potent US, is crucial to establish context conditioning.

West African savannas are habitats with unpredictable rainfall. Species with varying life-history traits may be more successful in these environments than species with fixed traits. We studied the reproduction strategies of the microhylid frog Phrynomantis microps in different savanna types, a humid savanna in Ivory Coast and a drier one in Benin. We recorded 5437 clutches in eight ponds in the humid savanna during five consecutive rainy seasons. A further 694 clutches were investigated in 10 ponds in Benin in one rainy season. For each clutch, we recorded egg numbers, deposition time, location within the pond and rainfall. Precipitation was important in triggering reproduction. However, the amount of rainfall needed differed in relation to rainy season length and total annual rainfall. Especially in years and regions with a late rainy season a threshold of minimum precipitation was needed to initiate spawning, indicating a trade-off between the need to reproduce and the survival probabilities of offspring in ponds with a high desiccation risk. Egg numbers per clutch further differed between pond sizes, breeding season length, as well as to time within the rainy season. Potential explanations for these differences, in particular desiccation and predation risks are discussed, but need further experimental support.

What is creativity? One new idea may be creative, whereas another is merely new: What's the difference? And how is creativity possible? These questions about human creativity can be answered, at least in outline, using computational concepts. There are two broad types of creativity, improbabilist and impossibilist. Improbabilist creativity involves (positively valued) novel combinations of familiar ideas. A deeper type involves METCS: the mapping, exploration, and transformation of conceptual spaces. It is impossibilist, in that ideas may be generated which – with respect to the particular conceptual space concerned – could not have been generated before. (They are made possible by some transformation of the space.) The more clearly conceptual spaces can be defined, the better we can identify creative ideas. Defining conceptual spaces is done by musicologists, literary critics, and historians of art and science. Humanist studies, rich in intuitive subtleties, can be complemented by the comparative rigour of a computational approach. Computational modelling can help to define a space, and to show how it may be mapped, explored, and transformed. Impossibilist creativity can be thought of in “classical” Al terms, whereas connectionism illuminates improbabilist creativity. Most Al models of creativity can only explore spaces, not transform them, because they have no self-reflexive maps enabling them to change their own rules. A few, however, can do so. A scientific understanding of creativity does not destroy our wonder at it, nor does it make creative ideas predictable. Demystification does not imply dehumanization.

A 16-year study of wild, unprovisioned sifaka Propithecus verreauxi verreauxi at Beza Mahafaly in south-west Madagascar provides estimates of age-specific fertility, mortality, and dispersal in a population of 426 marked animals, and longitudinal records of individual life histories. Sifaka females give birth for the first time later and live longer, for their size, than mammals in other orders; they also give birth later and continue reproducing longer, for their size, than other primates. Theory postulates that these features, commonly referred to as bet-hedging, evolve in unpredictable environments in association with widely varying infant survival and a trade-off between reproductive effort and adult survival. The climate of south-west Madagascar is highly unpredictable compared to almost all other regions in the tropics with similar average rainfall, and we argue that sifaka females are bet-hedgers par excellence. Male sifaka, in contrast, become reproductively active at an earlier age than females, and are less likely to have long lives than females. The atypical direction of this asymmetry between males and females reflects a ‘slowing down’ of female life histories rather than a ‘speeding up’ of male life histories. Two other unusual features of sifaka biology and behaviour may be linked to the unpredictability of Madagascar's climate: intense local competition between females, and a sex ratio at birth strongly biased in favour of males in most years. In drought years, reproductive females must cope with suddenly intensified resource constraints. This, in turn, may strongly limit the number of ‘breeding slots’ available over the long-term for females.