Cultures Crossing: The Power of Habit in Delaying Gratification.

Resisting immediate temptations in favor of larger later rewards predicts academic success, socioemotional competence, and health. These links with delaying gratification appear from early childhood and have been explained by cognitive and social factors that help override tendencies toward immediate gratification. However, some tendencies may actually promote delaying gratification. We assessed children's delaying gratification for different rewards across two cultures that differ in customs around waiting. Consistent with our preregistered prediction, results showed that children in Japan (n = 80) delayed gratification longer for food than for gifts, whereas children in the United States (n = 58) delayed longer for gifts than for food. This interaction may reflect cultural differences: Waiting to eat is emphasized more in Japan than in the United States, whereas waiting to open gifts is emphasized more in the United States than in Japan. These findings suggest that culturally specific habits support delaying gratification, providing a new way to understand why individuals delay gratification and why this behavior predicts life success.

Understanding and Supporting Inhibitory Control: Unique Contributions From Proactive Monitoring and Motoric Stopping to Children's Improvements With Practice.

Children struggle to stop inappropriate behaviors. What interventions improve inhibitory control, for whom, and why? Prior work suggested that practice proactively monitoring for relevant signals improved children's inhibitory control more than practice with motoric stopping. However, these processes were not clearly dissociated. This study tested 162 seven- to nine-year-old children (89 female, 72 male, 1 unreported; 82% White) on the stop-signal task, following monitoring or stopping-focused practice. Both methods improved inhibitory control, supported generalization, and interacted ( η p 2 = .20-.73). Practice approaches differentially impacted variability ( η p 2 = .01-.09). Only monitoring benefits showed signs of depending upon proactive control ( η p 2 = .02). These findings highlight unique contributions of attentional and stopping processes to inhibitory control, suggesting possibilities for tailored interventions.

Same Data Set, Different Conclusions: Preschool Delay of Gratification Predicts Later Behavioral Outcomes in a Preregistered Study.

One simple marshmallow test in preschool children predicts an array of important life outcomes, according to multiple studies spanning several decades. However, a recent conceptual replication casts doubt on these famous findings. We conducted an independent, preregistered secondary analysis to test whether previously observed longitudinal associations between preschool delay of gratification and adolescent outcomes would be conceptually replicated. Associations were significant for three of the five outcomes we tested using the analytic approach employed in the original studies of the marshmallow test. Relationships between delay of gratification and problem behavior held in bivariate, multivariate, and multilevel models; in contrast, no significant relationships between delay and problem behavior were found in the other recent replication, even though both studies used the same data set. These relationships were better explained by social support than by self-control, suggesting that the marshmallow test is predictive because it reflects aspects of a child's early environment that are important over the long term. This novel interpretation of the classic findings points to new directions for intervention.

Group Influences on Engaging Self-Control: Children Delay Gratification and Value It More When Their In-Group Delays and Their Out-Group Doesn't.

Self-control emerges in a rich sociocultural context. Do group norms around self-control influence the degree to which children use it? We tested this possibility by assigning 3- to 5-year-old children to a group and manipulating their beliefs about in-group and out-group behavior on the classic marshmallow task. Across two experiments, children waited longer for two marshmallows when they believed that their in-group waited and their out-group did not, compared with children who believed that their in-group did not wait and their out-group did. Group behavior influenced children to wait more, not less, as indicated by comparisons with children in a control condition who were assigned to a group but received no information about either groups' delay behavior (Experiment 1). Children also subsequently valued delaying gratification more if their in-group waited and their out-group did not (Experiment 2). Childhood self-control behavior and related developmental outcomes may be shaped by group norms around self-control, which may be an optimal target for interventions.

Using language to get ready: Familiar labels help children engage proactive control.

A key developmental transition is the ability to engage executive functions proactively in advance of needing them. We tested the potential role of linguistic processes in proactive control. Children completed a task in which they could proactively track a novel (target) shape on a screen as it moved unpredictably amid novel distractors and needed to identify where it disappeared. Children almost always remembered which shape to track, but those who learned familiar labels for the target shapes before the task had nearly twice the odds of tracking the target compared with those who received experience with the targets but no labels. Children who learned labels were also more likely to spontaneously vocalize labels when the target appeared. These findings provide the first evidence of a causal role for linguistic processes in proactive control and suggest new ideas about how proactive control develops, why language supports a variety of executive functions, and how interventions might best be targeted.

Beyond personal control: The role of developing self-control abilities in the behavioral constellation of deprivation.

We agree with Pepper & Nettle that personal control is important in understanding people's willingness to engage in future-oriented behavior. However, this does not imply that self-control abilities play no role, for self-control abilities do influence whether individuals engage in future-oriented behavior. Personal control may also shape the development of self-control abilities, so contrasting the two may be a false dichotomy.

Trust matters: Seeing how an adult treats another person influences preschoolers' willingness to delay gratification.

Holding out for a delayed reward in the face of temptation is notoriously difficult, and the ability to do so in childhood predicts diverse indices of life success. Prominent explanations focus on the importance of cognitive control. However, delaying gratification may also require trust in people delivering future rewards as promised. Only limited experimental work has tested this idea, and such studies with children were focused on general reward expectations, so evidence was ambiguous as to whether social trust played a role. The present study provides the first targeted test of a role for social trust in children's willingness to delay gratification. Children observed an adult behave in either a trustworthy or untrustworthy manner toward another adult, then were tested in the classic delay of gratification task by that adult. Children were less likely to wait the full delay period, and waited less time overall, for a reward promised by an untrustworthy adult, relative to children tested by a trustworthy adult. These findings demonstrate that manipulations of social trust influence delaying gratification, and highlight intriguing alternative reasons to test for individual differences in delaying gratification and associated life outcomes.

Metacognitive processes in executive control development: the case of reactive and proactive control.

Young children engage cognitive control reactively in response to events, rather than proactively preparing for events. Such limitations in executive control have been explained in terms of fundamental constraints on children's cognitive capacities. Alternatively, young children might be capable of proactive control but differ from older children in their metacognitive decisions regarding when to engage proactive control. We examined these possibilities in three conditions of a task-switching paradigm, varying in whether task cues were available before or after target onset. RTs, ERPs, and pupil dilation showed that 5-year-olds did engage in advance preparation, a critical aspect of proactive control, but only when reactive control was made more difficult, whereas 10-year-olds engaged in proactive control whenever possible. These findings highlight metacognitive processes in children's cognitive control, an understudied aspect of executive control development.

Time Isn't of the Essence: Activating Goals Rather Than Imposing Delays Improves Inhibitory Control in Children.

Is it easier to inhibit inappropriate behaviors if one pauses before acting? An important finding for theory and intervention is that children's inhibitory control improves if an adult imposes a delay before they can act. Such findings have suggested that the passage of time allows impulsive urges to dissipate passively. However, in prior studies with imposed delays, children were also reminded about what they should be doing, which may have aided their activation of goal-relevant information. We tested this possibility by independently manipulating delays and task reminders, and measuring 3-year-olds' abilities to inhibit opening boxes in a go/no-go box-search task. Task reminders, but not adult-imposed delays, improved children's response inhibition. However, as in prior work, children who spontaneously delayed their action longer on go trials exhibited better response inhibition on no-go trials. These results pose a challenge to the view that the passage of time plays a causal role, suggest that spontaneous delays index other processes that improve inhibitory control, and highlight the importance of goal activation in developing inhibitory control.

All competition is not alike: neural mechanisms for resolving underdetermined and prepotent competition.

People must constantly select among potential thoughts and actions in the face of competition from (a) multiple task-relevant options (underdetermined competition) and (b) strongly dominant options that are not appropriate in the current context (prepotent competition). These types of competition are ubiquitous during language production. In this work, we investigate the neural mechanisms that allow individuals to effectively manage these cognitive control demands and to quickly choose words with few errors. Using fMRI, we directly contrast underdetermined and prepotent competition within the same task (verb generation) for the first time, allowing localization of the neural substrates supporting the resolution of these two types of competition. Using a neural network model, we investigate the possible mechanisms by which these brain regions support selection. Together, our findings demonstrate that all competition is not alike: resolving prepotent competition and resolving underdetermined competition rely on partly dissociable neural substrates and mechanisms. Specifically, activation of left ventrolateral pFC is specific to resolving underdetermined competition between multiple appropriate responses, most likely via competitive lateral inhibition. In contrast, activation of left dorsolateral pFC is sensitive to both underdetermined competition and prepotent competition from response options that are inappropriate in the current context. This region likely provides top-down support for task-relevant responses, which enables them to out-compete prepotent responses in the selection process that occurs in left ventrolateral pFC.

Individual differences in the balance of GABA to glutamate in pFC predict the ability to select among competing options.

Individuals vary greatly in their ability to select one item or response when presented with a multitude of options. Here we investigate the neural underpinnings of these individual differences. Using magnetic resonance spectroscopy, we found that the balance of inhibitory versus excitatory neurotransmitters in pFC predicts the ability to select among task-relevant options in two language production tasks. The greater an individual's concentration of GABA relative to glutamate in the lateral pFC, the more quickly he or she could select a relevant word from among competing options. This outcome is consistent with our computational modeling of this task [Snyder, H. R., Hutchison, N., Nyhus, E., Curran, T., Banich, M. T., O'Reilly, R. C., et al. Neural inhibition enables selection during language processing. Proceedings of the National Academy of Sciences, U.S.A., 107, 16483-16488, 2010], which predicts that greater net inhibition in pFC increases the efficiency of resolving competition among task-relevant options. Moreover, the association with the GABA/glutamate ratio was specific to selection and was not observed for executive function ability in general. These findings are the first to link the balance of excitatory and inhibitory neural transmission in pFC to specific aspects of executive function.

Costs and benefits linked to developments in cognitive control.

Developing cognitive control over one's thoughts, emotions, and actions is a fundamental process that predicts important life outcomes. Such control begins in infancy, and shifts during development from a predominantly reactive form (e.g. retrieving task-relevant information when needed) to an increasingly proactive form (e.g. maintaining task-relevant information in anticipation of needing it). While such developments are generally viewed as adaptive, cognitive abilities can also involve trade-offs, such that the benefits of developing increasingly proactive control may come with associated costs. In two experiments, we test for such cognitive trade-offs in children who are transitioning to proactive control. We find that proactive control predicts expected benefits in children's working memory, but is also associated with predicted costs in disproportionately slowing children under conditions of distraction. These findings highlight unique advantages and disadvantages of proactive and reactive control, and suggest caution in attempting to alter their balance during development.

Opposite effects of anxiety and depressive symptoms on executive function: the case of selecting among competing options.

People constantly face the need to choose one option from among many, such as when selecting words to express a thought. Selecting between many options can be difficult for anyone, and can feel overwhelming for individuals with elevated anxiety. The current study demonstrates that anxiety is associated with impaired selection across three different verbal tasks, and tests the specificity of this finding to anxiety. Anxiety and depression frequently co-occur; thus, it might be assumed that they would demonstrate similar associations with selection, although they also have distinct profiles of symptoms, neuroanatomy and neurochemistry. Here, we report for the first time that anxiety and depressive symptoms counter-intuitively have opposite effects on selection among competing options. Specifically, whereas anxiety symptoms are associated with impairments in verbal selection, depressive symptoms are associated with better selection performance. Implications for understanding the mechanisms of anxiety, depression and selection are discussed.

The nature and nurture of high IQ: an extended sensitive period for intellectual development.

IQ predicts many measures of life success, as well as trajectories of brain development. Prolonged cortical thickening observed in individuals with high IQ might reflect an extended period of synaptogenesis and high environmental sensitivity or plasticity. We tested this hypothesis by examining the timing of changes in the magnitude of genetic and environmental influences on IQ as a function of IQ score. We found that individuals with high IQ show high environmental influence on IQ into adolescence (resembling younger children), whereas individuals with low IQ show high heritability of IQ in adolescence (resembling adults), a pattern consistent with an extended sensitive period for intellectual development in more-intelligent individuals. The pattern held across a cross-sectional sample of almost 11,000 twin pairs and a longitudinal sample of twins, biological siblings, and adoptive siblings.

Speed isn't everything: complex processing speed measures mask individual differences and developmental changes in executive control.

The rate at which people process information appears to influence many aspects of cognition across the lifespan. However, many commonly accepted measures of 'processing speed' may require goal maintenance, manipulation of information in working memory, and decision-making, blurring the distinction between processing speed and executive control and resulting in overestimation of processing speed contributions to cognition. This concern may apply particularly to studies of developmental change, as even seemingly simple processing speed measures may require executive processes to keep children and older adults on task. We report two new studies and a re-analysis of a published study, testing predictions about how different processing speed measures influence conclusions about executive control across the lifespan. We find that the choice of processing speed measure affects the relationship observed between processing speed and executive control, in a manner that changes with age, and that choice of processing speed measure affects conclusions about development and the relationship among executive control measures. Implications for understanding processing speed, executive control, and their development are discussed.

So many options, so little control: abstract representations can reduce selection demands to increase children's self-directed flexibility.

Children often struggle to behave flexibly when they must use self-directed goals (e.g., doing homework without prompting) rather than externally driven goals (e.g., cleaning up when told). Such struggles may reflect the demands of selecting among many potential options, as required for self-directed control. The current study tested whether (a) 6-year-old children show difficulty in selecting among competing semantic representations, (b) providing category labels designed to reduce selection demands improves performance, and (c) such benefits transfer to self-directed flexibility. Selection was measured using the blocked cyclic naming task for the first time with children. Pictures were named repeatedly in either homogeneous blocks from the same category (e.g., all animals), which create high selection demands due to spreading semantic activation and engage effortful cognitive control, or mixed blocks with each picture from a different category. Children showed robust difficulty in selecting among options, as indexed by response time (RT) differences between homogeneous and mixed blocks. Providing subcategory labels designed to reduce selection demands by distinguishing among same-category items (e.g., "A cow is a farm animal. A cat is a pet.") improved selection. Providing superordinate categories (e.g., "A cow is an animal. A cat is an animal.") also improved selection, but these benefits were less robust, and subcategory labels led to greater benefits than superordinate category labels on a subsequent verbal fluency task. These results support a role for subcategory representations in reducing selection demands to aid self-directed flexibility while suggesting that some children may use superordinate category labels to activate subcategory representations on their own.

Neural inhibition enables selection during language processing.

Whether grocery shopping or choosing words to express a thought, selecting between options can be challenging, especially for people with anxiety. We investigate the neural mechanisms supporting selection during language processing and its breakdown in anxiety. Our neural network simulations demonstrate a critical role for competitive, inhibitory dynamics supported by GABAergic interneurons. As predicted by our model, we find that anxiety (associated with reduced neural inhibition) impairs selection among options and associated prefrontal cortical activity, even in a simple, nonaffective verb-generation task, and the GABA agonist midazolam (which increases neural inhibition) improves selection, whereas retrieval from semantic memory is unaffected when selection demands are low. Neural inhibition is key to choosing our words.

The Development of Relational Reasoning: An Eyetracking Analysis of Strategy Use and Adaptation in Children and Adults Performing Matrix Completion.

Relational reasoning is a key component of fluid intelligence and an important predictor of academic achievement. Relational reasoning is commonly assessed using matrix completion tasks, in which participants see an incomplete matrix of items that vary on different dimensions and select a response that best completes the matrix based on the relations among items. Performance on such assessments increases dramatically across childhood into adulthood. However, despite widespread use, little is known about the strategies associated with good or poor matrix completion performance in childhood. This study examined the strategies children and adults use to solve matrix completion problems, how those strategies change with age, and whether children and adults adapt strategies to difficulty. We used eyetracking to infer matrix completion strategy use in 6- and 9-year-old children and adults. Across ages, scanning across matrix rows and columns predicted good overall performance, and quicker and higher rates of consulting potential answers predicted poor performance, indicating that optimal matrix completion strategies are similar across development. Indices of good strategy use increased across childhood. As problems increased in difficulty, children and adults increased their scanning of matrix rows and columns, and adults and 9-year-olds also shifted strategies to rely more on consulting potential answers. Adapting strategies to matrix difficulty, particularly increased scanning of rows and columns, was associated with good overall performance in both children and adults. These findings underscore the importance of both spontaneous and adaptive strategy use in individual differences in relational reasoning and its development.

Why doesn't executive function training improve academic achievement? Rethinking individual differences, relevance, and engagement from a contextual framework.

Performance on lab assessments of executive functions predicts academic achievement and other positive life outcomes. A primary goal of research on executive functions has been to design interventions that improve outcomes like academic achievement by improving executive functions. These interventions typically involve extensive practice on abstract lab-based tasks and lead to improvements on these practiced tasks. However, interventions rarely improve performance on non-practiced tasks and rarely benefit outcomes like academic achievement. Contemporary frameworks of executive function development suggest that executive functions develop and are engaged within personal, social, historical, and cultural contexts. Abstract lab-based tasks do not well-capture the real-world contexts that require executive functions and should not be expected to provide generalized benefits outside of the lab. We propose a perspective for understanding individual differences in performance on executive function assessments that focuses on contextual influences on executive functions. We extend this contextual approach to training executive function engagement, rather than training executive functions directly. First, interventions should incorporate task content that is contextually relevant to the targeted outcome. Second, interventions should encourage engaging executive functions through reinforcement and contextual relevance, which may better translate to real-world outcomes than training executive functions directly. While such individualized executive functions interventions do not address systemic factors that greatly impact outcomes like academic achievement, given the extensive resources devoted to improving executive functions, we hypothesize that interventions designed to encourage children's engagement of executive functions hold more promise for impacting real-world outcomes than interventions designed to improve executive function capacities.