Article

Uniquely human self-control begins at school age

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Abstract

Human beings have remarkable skills of self-control, but the evolutionary origins of these skills are unknown. Here we compare children at 3 and 6 years of age with one of humans’ two nearest relatives, chimpanzees, on a battery of reactivity and self-control tasks. Three-year-old children and chimpanzees were very similar in their abilities to resist an impulse for immediate gratification, repeat a previously successful action, attend to a distracting noise, and quit in the face of repeated failure. Six-year-old children were more skillful than either 3-year-olds or chimpanzees at controlling their impulses. These results suggest that humans’ most fundamental skills of self-control – as part of the overall decision-making process – are a part of their general great ape heritage, and that their species-unique skills of self-control begin at around the age at which many children begin formal schooling.

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... Similarly, Gräfenhain et al. (2009) found that 4-year-olds took longer to leave a (joint or parallel) game than 3-year-olds. In addition, studies on the development of children's self-control have shown that with increasing age children are better able to regulate their actions (e.g., stop repeating a previously successful action that is no longer effective) and attention (e.g., focus despite a distracting noise) (Herrmann, Misch, Hernandez-Lloreda, & Tomasello, 2015). Thus, older children are better at focusing on their current task/game and are less easily distracted to explore a more attractive activity, which may explain the developmental findings in our study. ...
... The finding that young children do already understand some normative implications of promising does not imply that there are no developmental changes in promise-related behaviors or that children always keep their promises. For one, we found that across conditions older children were more committed to our cleaning task (Studies 2 and 3), which is most likely related to developmental changes in children's abilities for self-control (Herrmann et al., 2015). This explanation has been championed by other authors (Heyman et al., 2015) to explain why younger children in their study were not affected by promises. ...
Article
Promises are speech acts that create an obligation to do the promised action. In three studies, we investigated whether 3- and 5-year-olds (N = 278) understand the normative implications of promising in prosocial interactions. In Study 1, children helped a partner who promised to share stickers. When the partner failed to uphold the promise, 3- and 5-year-olds protested and referred to promise norms. In Study 2, when children in this same age range were asked to promise to continue a cleaning task—and they agreed—they persisted longer on the task and mentioned their obligation more frequently than without such a promise. They also persisted longer after a promise than after a cleaning reminder (Study 3). In prosocial interactions, thus, young children feel a normative obligation to keep their promises and expect others to keep their promises as well.
... Nonetheless, this should not obscure the fact that most animals only wait for a few seconds for a reward, and chimpanzees for a few minutes (e.g., Dufour et al., 2007), whereas humans can delay their gratification for days, months or even years. Indeed, self-control in the face of immediate temptations continues to be considered a defining human ability (Baumeister, 2014;Baumeister & Tierney, 2011;Herrmann, Misch, Hernandez-Lloreda, & Tomasello, 2014;Vohs et al., 2014). ...
... As already noted, a capacity for self-control in the face of competing temptations is widely considered to be a fundamental and critical human capacity (Baumeister & Tierney, 2011;Diamond, 2013;Herrmann et al., 2014;Tangney, Baumeister, & Boone, 2004;Vohs & Baumeister, 2011). Deciding to indulge in immediate rewards in favor of larger but delayed ones has often been considered as resulting from a lack of self-control (Logue, 1988;Mazur & Logue, 1978;Rachlin, 1974), or to reflect a reduced capacity for self-regulation in the face of impulses (Tangney et al., 2004). ...
Article
Humans are capable of imagining future rewards and the contexts in which they may be obtained. Functionally, intertemporal choices between smaller but immediate and larger but delayed rewards may be made without such episodic foresight. However, we propose that explicit simulations of this sort enable more flexible and adaptive intertemporal decision-making. Emotions triggered through the simulation of future situations can motivate people to forego immediate pleasures in the pursuit of long-term rewards. However, we stress that the most adaptive option need not always be a larger later reward. When the future is anticipated to be uncertain, for instance, it may make sense for preferences to shift toward more immediate rewards, instead. Imagining potential future scenarios and assessment of their likelihood and affective consequences allows humans to determine when it is more adaptive to delay gratification in pursuit of a larger later reward, and when the better strategy is to indulge in a present temptation. We discuss clinical studies that highlight when and how the effect of episodic foresight on intertemporal decision-making can be altered, and consider the relevance of this perspective to under- standing the nature of self-control. Keywords: episodic foresight, prospection, intertemporal choice, delay discounting, evolution
... All subjects participated in a task in which their persistence in trying to obtain a reward (that was suddenly impossible to get) was examined (figure 2; [25]). In a pre-test, the subject was given a transparent box that contained a toy token (children) or a piece of banana (chimpanzee) and was shown how to open the box. ...
Article
Facial expressions have long been proposed to be important agents in forming and maintaining cooperative interactions in social groups. Human beings are inordinately cooperative when compared with their closest-living relatives, the great apes, and hence one might expect species differences in facial expressivity in contexts in which cooperation could be advantageous. Here, human children and chimpanzees were given an identical task designed to induce an element of frustration (it was impossible to solve). In children, but not chimpanzees, facial expressions associated with effort and determination positively correlated with persistence at the task. By contrast, bodily indicators of stress (self-directed behaviour) negatively correlated with task persistence in chimpanzees. Thus, children exhibited more behaviour as they persisted, and chimpanzees exhibited less. The facial expressions produced by children, could, therefore, function to solicit prosocial assistance from others.
... At 3 y of age, children begin to develop species-unique skills for coordinating multiple mental states in a single task. This fact is evidenced by studies finding that human children's skills of executive function, including coordinating perspectives, only go beyond those of apes beginning at about 3 or 4 y of age (73,74). These skills, which are at least to some degree domain general (the degree of this generality is open for debate), seem to be responsible for young children's ability to compare and coordinate their own and others' perspectives as different attitudes to mental representations, including propositions. ...
Article
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Significance In coming to understand minds, the greatest challenge for young children is understanding when others have a false belief. Why is that person searching for the toy over there when it is really over here? There is currently much controversy about when children come to this understanding because experiments of different types yield different results. This paper attempts to resolve the controversy by integrating theory and data in a different way. Specifically, the paper argues that young children do not just come to imagine what is in other minds on their own; rather, they come to this understanding through certain types of social and communicative interactions with others that require them to compare their respective perspectives.
... Children's understanding of goal-pursuit behaviors in situations when goals and preferences conflict might be relevant to a variety of behaviors in self-regulation, prosocial, or learning situations. Between preschool and middle childhood years, children become increasingly able to prioritize their future self and control present impulses (e.g., Atance & Meltzoff, 2006;Herrmann et al., 2015;Metcalf & Atance, 2011;Mischel et al., 1972;Mischel et al., 1989). In the interpersonal domain, 7-and 8-year-olds are more able than preschoolers to have other regarding preferences and share in egalitarian ways (Fehr et al., 2008), as well as being more aware of the emotional benefits for making prosocial sacrifices (Weller & Lagattuta, 2013. ...
Thesis
Having internal conflicting desires is a frequent life experience. Despite the abundant literature on children's understanding of simple mental states, little is known about their reasoning about conflicting desires. Across six studies, from developmental, social-cognitive and cross-cultural perspectives, the present dissertation investigates the development of understanding internal conflicts, sociocultural influences in its development, as well as its links with children's socioemotional development. In Part 1, to examine the development of understanding conflicting desires, 4- to 7-year-old U.S. children were told stories in which the character had an overall goal (e.g., lose weight) and a conflicting immediate preference (e.g., like chocolate but not broccoli). When asked to predict the character's action, 6- to 7-year-olds predicted she would act according to the main goal, whereas younger children predicted she would act to satisfy the immediate desire. In Part 2, to investigate cultural influence on the development, Chinese children's understanding was examined. Five-yearold Chinese children gave goal-oriented responses to the conflicting desire stories, at least one year earlier than their American counterparts. Part 3 explored links between understanding of conflicting desires and social-emotional development. U.S. and Chinese children's key socioemotional characteristics were measured by peer nominations, teacher-ratings and self-reports. Associations between understanding of conflicting desires and positive socioemotional adjustments were found among Chinese children, but not among U.S. children. The present findings suggest that an understanding of internal conflicting desires develops during childhood, facilitated by relevant sociocultural input. In the context where dealing with internal conflicts is emphasized early in life, better understanding of internal conflicts is related with positive socioemotional development.
... The ability of children to delay gratification has been shown to be a reliable predictor of future academic success. Human self-control begins at school age between 3 and 6 years old and represents a crucial stage of differentiation of humans from our nearest relative the chimpanzee (Herrmann et al. 2014). Suggesting that self-control is a key cognitive development in our evolutionary development, forming a unique component of human decision making processes associated with learning. ...
... Another explanation for the difference between 3-year-olds and 5-year-olds could lie in their ability to control their impulses. Compared with older children, 3-year-olds possess less advanced inhibitory control (Carlson & Moses, 2001;Herrmann, Misch, Hernandez-Lloreda, & Tomasello, 2015; N Female Male Fig. 4. Numbers of spades that 3-year-olds cleaned up, separated by condition and gender. Data points are depicted by dots, with bigger dots representing more data points. ...
Article
The current study explored how freedom of choice affects preschoolers’ prosocial motivation. Children (3- and 5-year-olds) participated in either a choice condition (where they could decide for themselves whether to help or not) or a no-choice condition (where they were instructed to help). Prosocial motivation was subsequently assessed by measuring the amount children helped an absent peer in the face of an attractive alternative game. The 5-year-olds provided with choice helped more than the children not provided with choice, and this effect was stronger for girls than for boys. There was no difference between conditions for the 3-year-olds. These results highlight the importance of choice in young children’s prosocial development.
... Another component of executive control concerns reactivity to novel contexts [68,69]: do individuals seek out or avoid new aspects of the environment or new social partners? This aspect of self-regulation is a key component of flexibility in response to novel contexts and appears to cut across both social behavior (reactions to other agents) and foraging behavior (reactions to food or objects in the physical environment). ...
Article
What are the origins of intelligent behavior? The demands associated with living in complex social groups have been the favored explanation for the evolution of primate cognition in general and human cognition in particular. However, recent comparative research indicates that ecological variation can also shape cognitive abilities. I synthesize the emerging evidence that ‘foraging cognition’ – skills used to exploit food resources, including spatial memory, decision-making, and inhibitory control – varies adaptively across primates. These findings provide a new framework for the evolution of human cognition, given our species’ dependence on costly, high-value food resources. Understanding the origins of the human mind will require an integrative theory accounting for how humans are unique in both our sociality and our ecology.
... In addition to temperamental orienting/regulation, the percentage of time spent in distractions during the mealtime was also associated with fewer bites per minute. Since young children have shorter attention spans (i.e., divided attention, selective attention), which improves with age, it may be more challenging for a child to switch focus between eating and the source of distractions at this particular age (Herrmann et al., 2015;Veer et al., 2017). Therefore, it is possible that children at this age are more likely to withdraw from eating when distracted rather than managing concurrent engagement in eating while being attentive to the source of distraction, including technological distractions accompanied by decreased bite speed. ...
Article
Eating behaviors are shaped at an early age, persist into adulthood, and are implicated in the development of physical health outcomes, including obesity. Faster bite speed has been identified as an obesogenic eating behavior, prompting researchers to examine child and family factors associated with children's variability in bite speed. Child temperament, involving phenotypes of reactivity and regulation, and distractions in family food contexts are fruitful areas of investigation, but few studies have examined the interplay among these factors and their associations with bite speed. To address the gap in the literature, we examined relations between early child temperament, family mealtime distractions, and children's observed bite speed. Caregiver report of child temperament at 3 months was measured using the Infant Behavior Questionnaire Very Short Form - Revised. Child mealtime distractions and bite speed were assessed using family mealtime videos that were collected during home visits when children were 18–24 months of age (n = 109). Results revealed that children who were reported to be higher on orienting/regulation at 3 months, and who were more distracted during mealtimes at 18–24 months, had relatively slower bite speeds. No significant interactions were found. The findings from this correlational study inform further investigations into the implications of early temperament and food contexts for the development of eating behaviors implicated in obesity risk.
... Children's understanding of goal-pursuit behaviors in situations when goals and preferences conflict might be relevant to a variety of behaviors in self-regulation, prosocial, or learning situations. Between preschool and middle childhood years, children become increasingly able to prioritize their future self and control present impulses (e.g., Atance & Meltzoff, 2006;Herrmann et al., 2015;Metcalf & Atance, 2011;Mischel et al., 1972;Mischel et al., 1989). In the interpersonal domain, 7-and 8-year-olds are more able than preschoolers to have other regarding preferences and share in egalitarian ways (Fehr et al., 2008), as well as being more aware of the emotional benefits for making prosocial sacrifices (Weller & Lagattuta, 2013. ...
Article
Full-text available
Across three studies, we examined 4- to 7-year-olds’ predictions of goal-directed behaviors when goals conflict with preferences. In Study 1, when presented with stories in which a character had to act against basic preferences to achieve an interpersonal goal (e.g., playing with a partner), 6- and 7-year-olds were more likely than 4- and 5-year-olds to predict the actor would act in accordance with the goal to play with the partner, instead of fulfilling the basic preference of playing a favored activity. Similar results were obtained in Study 2 with scenarios that each involved a single individual pursuing intrapersonal goals that conflicted with his or her basic preferences. In Study 3, younger children’s predictions of goal-directed behaviors did not increase for novel goals and preferences, when the influences of their own preferences, future thinking, or a lack of impulse control were minimized. The results suggest that between ages 4 and 7, children increasingly integrate and give more weight to other sources of motivational information (e.g., goals) in addition to preferences when predicting people’s behaviors. This increasing awareness may have implications for children’s self-regulatory and goal pursuit behaviors.
... Furthermore, this condition required advanced cognitive abilities (e.g., future planning, social perspective taking, memory, self-regulation) and the ability to integrate multiple study demands (e.g., keeping in mind the relevance of the second game while playing the first one). Because such abilities are known to undergo important changes in ontogeny (Banerjee, 2002b;Davidson, Amso, Anderson, & Diamond, 2006;Herrmann, Misch, Hernandez-Lloreda, & Tomasello, 2015;Selman, 1971;Wellman, Fabricius, & Sophian, 1985), the development of these abilities may have played a role in producing the observed age differences in this study. In addition, in comparison with previous studies (e.g., Benenson, Pascoe, & Radmore, 2007;Smith, Blake, & Harris, 2013), the described differences in methods may also account for different developmental patterns of sharing with a decrease in total sharing rates with age. ...
... Although it thus appears unlikely that social drama is fully responsible for primates' success in [25][26][27], it is possible that apes failed previous explicit tests because of task demands [70] (e.g., inhibitory control demands in paradigms involving food). However, apes have demonstrated strong self-control across a range of contexts [71][72][73][74][75], exceeding that of young children [76] and sometimes even of adult humans [77], making it unlikely that inhibitory control demands fully account for apes' failures on explicit FB tests. ...
Article
Over two decades of research have produced compelling evidence that non-human primates understand some psychological states in other individuals but are unable to represent others’ beliefs. Recently, three studies employing anticipatory looking (AL) paradigms reported that non-human primates do show hints of implicitly understanding the beliefs of others. However, measures of AL have been increasingly scrutinized in the human literature owing to extensive replication problems. We argue that new reports of belief representation in non-human primates using AL should be interpreted cautiously because of methodological and theoretical challenges paralleling trends in the human literature. We explore how future work can address these challenges, and conclude by identifying new evolutionary questions raised by the prospect that non-human primates implicitly represent others’ beliefs without an explicit belief representation system that guides fitness-relevant behavior.
... Planning for a future imagined goal in this way would seem to require some new executive, that is reflective, cognitive skills. Such skills would also seem to be required when chimpanzees are able to perceive and resolve a goal conflict by comparing how the means to achieve different simultaneously present goals are incompatible but could be made compatible (Herrmann et al., 2015). ...
Article
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Chimpanzees and humans are close evolutionary relatives who behave in many of the same ways based on a similar type of agentive organization. To what degree do they experience the world in similar ways as well? Using contemporary research in evolutionarily biology and animal cognition, I explicitly compare the kinds of experience the two species of capable of having. I conclude that chimpanzees’ experience of the world, their experiential niche as I call it, is: (i) intentional in basically the same way as humans’; (ii) rational in the sense that it is self-critical and operates with logically structured causal and intentional inferences; but (iii) not normative at all in that it does not operate with “objective” evaluative standards. Scientific data do not answer philosophical questions, but they provide rich raw material for scientists and philosophers alike to reflect on and clarify fundamental psychological concepts.
... Similarly, ManyPrimates et al. 25 found a marked increase in short-term memory abilities in the lineage leading to the great apes. Studies that directly compared great apes and humans found evidence that this pattern of increasing capacity with increasing brain size continues: young human children outperform great apes in attentional control and inhibition [25][26][27][28] . While these studies are a crucial first step, they have only focused on a single construct and a single task at a time, so leave open the question of what mechanisms underpin these changes in capability. ...
Article
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Executive functions (EF) are a core aspect of cognition. Research with adult humans has produced evidence for unity and diversity in the structure of EF. Studies with preschoolers favour a 1-factor model, in which variation in EF tasks is best explained by a single underlying trait on which all EF tasks load. How EF are structured in nonhuman primates remains unknown. This study starts to fill this gap through a comparative, multi-trait multi-method test battery with preschoolers (N = 185) and chimpanzees (N = 55). The battery aimed at measuring working memory updating, inhibition, and attention shifting with three non-verbal tasks per function. For both species the correlations between tasks were low to moderate and not confined to tasks within the same putative function. Factor analyses produced some evidence for the unity of executive functions in both groups, in that our analyses revealed shared variance. However, we could not conclusively distinguish between 1-, 2- or 3-factor models. We discuss the implications of our findings with respect to the ecological validity of current psychometric research.
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After obtaining a sample of published, peer-reviewed articles from journals with high and low impact factors in social, cognitive, neuro-, developmental, and clinical psychology, we used a priori equations recently derived by Trafimow (Educational and Psychological Measurement, 77, 831–854, 2017; Trafimow & MacDonald in Educational and Psychological Measurement, 77, 204–219, 2017) to compute the articles’ median levels of precision. Our findings indicate that developmental research performs best with respect to precision, whereas cognitive research performs the worst; however, none of the psychology subfields excelled. In addition, we found important differences in precision between journals in the upper versus lower echelons with respect to impact factors in cognitive, neuro-, and clinical psychology, whereas the difference was dramatically attenuated for social and developmental psychology. Implications are discussed.
Chapter
Anthropogeny, “the study of the origin of humans” is an attempt to use all verifiable facts and ethical scientific methods to explain the origin of the species Homo sapiens. Only a transdisciplinary approach will allow to unravel the singularity that is the appearance of our species, the “planet-altering ape.” Such transdisciplinarity will have to involve fields as varied as linguistics and psychology, biomedicine and neuroscience, physical and chemical sciences, comparative primatology, climate sciences and geology, archeology and paleontology with much support from computer science. Humans present a striking paradox as they combine an obvious mammalian and primate nature with a distinct combination of numerous biological and behavioral traits, making them spectacular outlier among the living world. The time depth of many of the processes that shaped our species represents a formidable obstacle. New fossils, archeological finds, ancient DNA technology, and comparative genomics are providing key new information. Anthropogenists are still facing a staggering list of humbling unknowns about the age of onset of key human innovations. These include but are not restricted to the following: symbolic capacity, personal name or kinship terms, language, home base use, fire use/cooking, pair bonding, awareness of paternal kinship networks, projectile weapon use, composite tool use, fiber use, bodily modifications, and death rituals. The human phenomenon reflects idiosyncratic concatenations of unlikely events. Key factors likely include both opportunities and constraints stemming from massive physical and cultural niche construction by our species that has increasingly taken its evolutionary fate in its own hands.
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The challenge of studying human cognitive evolution is identifying unique features of our intelligence while explaining the processes by which they arose. Comparisons with nonhuman apes point to our early-emerging cooperative-communicative abilities as crucial to the evolution of all forms of human cultural cognition, including language. The human selfdomestication hypothesis proposes that these early-emerging social skills evolved when natural selection favored increased in-group prosociality over aggression in late human evolution. As a by-product of this selection, humans are predicted to show traits of the domestication syndrome observed in other domestic animals. In reviewing comparative, developmental, neurobiological, and paleoanthropological research, compelling evidence emerges for the predicted relationship between unique human mentalizing abilities, tolerance, and the domestication syndrome in humans. This synthesis includes a review of the first a priori test of the self-domestication hypothesis as well as predictions for future tests. Expected final online publication date for the Annual Review of Psychology Volume 68 is January 03, 2017. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Chapter
The chapter emphasizes the distinctiveness in humans of our extreme social skills and/or organization. It investigates the evolutionary and developmental origins of these skills. For example, are they innate, prepared, and core, or do they depend on gradual learning, for example, in imitation? The chapter includes work on social neuroscience, and emphasizes the frontalization process, as well as the mirror neuron system and the somatic marker hypothesis. Also, it refers to biobehavioral synchrony and physiological attunement that happens in the neonatal–parental embodied dance or intersubjectivity. Other more biological topics include the perception-action mechanism and supramodal perception. Generally, the models presented are quite biopsychosocial, including the “SOCIAL” model and ones of stress contagion and shared embodiment.
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Using a multidisciplinary approach, the present study complements ethological behaviour measurements with basic theoretical concepts, methods and approaches of the personality psychological trait paradigm. Its adoptability and usefulness for animal studies are tested exemplarily on a sample of 20 zoo-housed great apes (five of each of the following species): bonobos, Pan paniscus; chimpanzees, Pan troglodytes verus; gorillas, Gorilla gorilla gorilla; and orang-utans, Pongo pygmaeus abelii. Data on 76 single trait-relevant behaviours were recorded in a series of 14 laboratory-based situations and in two different group situations. Data collection was repeated completely after a break of 2 weeks within a 50-day period. All behaviour records were sufficiently reliable. Individual- and variable-oriented analyses showed high/substantial temporal stability on different levels of aggregation. Distinctive and stable individual situational and response profiles clarified the importance of situations and of multiple trait-relevant behaviours. The present study calls for a closer collaboration between behavioural biologists and personality psychologists to tap the full potential of animal personality research.
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Temperament dimensions influence children's approach to and participation in social interactive experiences which reflect and impact children's social understandings. Therefore, temperament differences might substantially impact theory of mind development in early childhood. Using longitudinal data, we report that certain early temperament characteristics (at age 3)--lack of aggressiveness, a shy-withdrawn stance to social interaction, and social-perceptual sensitivity--predict children's more advanced theory-of-mind understanding two years later. The findings contribute to our understanding of how theory of mind develops in the formative preschool period; they may also inform debates as to the evolutionary origins of theory of mind.
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Human and nonhuman animals show personality: temporal and contextual consistency in behavior patterns that vary among individuals. In contrast to most other species, personality of chimpanzees, Pan troglodytes, has mainly been studied with non-behavioral methods. We examined boldness, exploration tendency, persistence and tool-orientation in 29 captive chimpanzees using repeated experiments conducted in an ecologically valid social setting. High temporal repeatability and contextual consistency in all these traits indicated they reflected personality. In addition, Principal Component Analysis revealed two independent syndromes, labeled exploration-persistence and boldness. We found no sex or rank differences in the trait scores, but the scores declined with age. Nonetheless, there was considerable inter-individual variation within age-classes, suggesting that behavior was not merely determined by age but also by dispositional effects. In conclusion, our study complements earlier rating studies and adds new traits to the chimpanzee personality, thereby supporting the existence of multiple personality traits among chimpanzees. We stress the importance of ecologically valid behavioral research to assess multiple personality traits and their association, as it allows inclusion of ape studies in the comparison of personality structures across species studied behaviorally, and furthers our attempts to unravel the causes and consequences of animal personality. Am. J. Primatol. 9999:XX-XX, 2013. © 2013 Wiley Periodicals, Inc.
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The study of “metacognition” has become vigorous in recent years, with extensive research exploring the development of children’s knowledge of effective strategies in attention, comprehension, and memory (e.g., Brown, 1980; Flavell & Wellman, 1977). In contrast, the child’s developing understanding of essential strategies for self-regulation — a core aspect of human functioning, basic to virtually all conceptions of personality — has been neglected. Perhaps this neglect reflects the fact that until recently there were few objective criteria against which one could assess the relative efficacy of various strategies for self-control. Studies of the conditions that enhance or impede successful delay of gratification in children (e.g., Miller & Karniol, 1976a, 1976b; Mischel, 1974, 1981b; Toner, 1981; Toner & Smith, 1977; Yates, Lippett, & Yates, 1981) now provide a basis for assessing the child’s developing understanding against objective criteria of efficacy.
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In this research we examine the relation between executive function (EF) and false-belief (FB) understanding in young children. Specifically, we proposed that performance on tasks combining 2 executive demands: (a) working memory and (b) inhibitory control would be most predictive of performance on FB tasks. Forty-eight children between the ages of 3 and 5 years were given a battery of EF and FB measures. As predicted we found that performance on executive tasks that combined demands for memory and inhibitory control were highly predictive of performance on FB tasks. To further test the relation of EF and FB understanding we also introduced an experimental manipulation designed to reduce the working memory demands of FB tasks. This manipulation did not significantly improve performance. The results from this study provide support for the relation between EF and FB understanding, although the exact nature of the relation requires further clarification.
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The means used by young children to control their own emotions has received scant attention in the developmental literature. However, this competency represents an important aspect of developmental growth. This article emphasizes regulation of distress and negative emotions. It focuses on (a) the principles that underlie regulation of distress and negative emotions among infants and young children and (b) developmental trends that occur during the first few years of life. The role of caregivers is discussed as well. A goal is to offer ideas that lend themselves to hypothesis testing and empirical validation. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Infant, children, and adult chimpanzees were presented with a shuttlecock, rubber dog, rubber tube, live tortoise, and glass snake while their avoidance reactions were rated on a scale running from -4 to +4. After an analysis of their results in terms of the degree of approach or avoidance reaction to the various objects by subjects of different ages, the authors conclude, tentatively, that their data "supply no evidence of specific avoidance (fear) response prior to or apart from individual experience with a given type of object. Species experience as custom or tradition, and individual experience as meaningful, determine the presence, form, and strength of negative or positive response to an object or other stimulus complex." It is suggested that visual movement, intensity, abruptness, and suddenness and rapidity of change in the stimulus or stimulus complex are significant factors in the determination of the avoidance response. This study is regarded as preliminary to a more thorough investigation. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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The relations of observed parental warmth and positive expressivity and children's effortful control and ego control with children's high versus low emotional expressivity were examined in a 2-wave study of 180 children (M age = 112.8 months). There were quadratic relations between adults' reports of children's emotional expressivity and effortful control; moderate expressivity was associated with high effortful control. Structural equation models supported the hypothesis that children's ego overcontrol (versus undercontrol) mediated the relation between parental warmth or positive expressivity and children's emotional expressivity, although parenting at the follow-up did not uniquely predict in children's expressivity after controlling for the relations in these constructs over time. The alternative hypothesis that children's ego overcontrol elicited positive parenting and expressivity also was supported.
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The hypothesis that the relations of effortful control and impulsivity to children's agreeableness would be at least partly indirect through their resiliency was tested. Eighty-two children (M age=58.67 mos.) were participants. Children nominated peers on agreeableness and completed a behavioral measure of effortful control. Teachers and a subsample of parents reported on children's effortful control, impulsivity, resiliency, and agreeableness. In a structural equation model, effortful control predicted high agreeableness, and this relation was indirect through resiliency. Impulsivity predicted high resiliency and was negatively related to agreeableness. In an alternative model, effortful control predicted high resiliency indirectly through agreeableness and impulsivity was not related to agreeableness. A third model indicated that with the exception of a path from effortful control to agreeableness, agreeableness and resiliency did not predict effortful control or impulsivity. The findings suggest that effortful control and impulsivity may contribute to resiliency and agreeableness, that resiliency and agreeableness are interrelated, and that resilient children are not overly controlled.
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The social functioning of 64 young adolescents (10- to 12-year olds) was examined in relation to negative emotionality and regulation during early adolescence, as well as two, four, and six years earlier. Young adolescents who were viewed as relatively high in social functioning (i.e., high teacher-rated school social competence; low mother- or father-rated problem behavior) were generally viewed as relatively low on negative emotionality and high on regulatory abilities during early adolescence as well as two, four, and six years earlier. Furthermore, negative emotionality and regulation during early adolescence, and in some cases at previous time periods, contributed unique variance to the prediction of social functioning during early adolescence. Young adolescents who were consistently low in social functioning across time were higher on negative emotionality and lower on regulation than were young adolescents who were consistently high on social functioning over time.
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In this article we report a longitudinal extension of previous findings about the critical role of temperamental inhibitory or effortful control as the contributor to developing conscience in young children. A comprehensive observational battery, highly internally consistent, was developed to measure inhibitory control in 83 children at early school age who had been followed since toddlerhood and had been assessed using similar batteries at toddler and preschool age. We again confirmed the findings of robust longitudinal stability of inhibitory or effortful control, now from toddler to early school age, the increase with age, and gender differences, with girls outperforming boys. We also reaffirmed strong links, both contemporaneous and in the longitudinal sense, between in hibitory control and multiple, diverse measures of children's conscience at early school age, including observations of moral conduct, moral cognition, and moral self. The findings are discussed in view of the increasingly appreciated importance of temperament for critical aspects of socialization.
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Multiple measures of children's emotionality (emotional intensity and negative affectivity), regulation (including attentional and behavioral regulation and coping), and social functioning (teachers' reports of nonaggressive/socially appropriate behavior and prosocial/socially competent behavior; and parents' reports of problem behavior) were obtained for 6–8-year-olds. In addition, emotionality, attentional regulation, and coping were assessed 2 years previously. Social functioning was expected to be predicted by low negative emotionality and high levels of regulation. In general, the data supported the predictions, although the findings for parent reports of problem behavior were primarily for boys. Prediction of social functioning from measures of regulation and emotionality occurred primarily within a given context (school vs. home) rather than across contexts, even though there were relations across reporters within the school or home context. In addition, vagal tone, a marker of physiological regulation, was positively related to competent social functioning and emotionality/regulation for boys, but inversely related for girls.
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Seventy-four primates species (24 genera of six families) were presented with a nylon rope and a wooden cube, and their subsequent manipulations were recorded in detail. Five hundreds and six manipulation patterns were distinguished on the basis of the actions performed, body-parts used and relations to other objects. Inter-specific comparisons revealed three groups: (1) lemurs, marmosets, spider monkeys and leaf-eaters; (2) Old World monkeys except leaf-eaters; and (3) cebus monkeys and apes. The first group had the smallest repertoire of manipulations, in which only a few types of actions and body-parts were involved. The second and third groups had more varied modes of manipulation. Actions such as Roll, Rub and Slide, and use of fingers characterized these groups. Except for the lesser ape, their manipulations were frequently related with other objects. Moreover, actions such as Drape, Drop, Strike, Swing and Throw were typical of the third group. The factors producing such inter-specific differences in manipulations and the relations to tool use are discussed.
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This research tested the hypothesis that prudence and altruism, in situations involving future desires, follow a similar developmental course between the ages of 3 and 5 years. Using a modified delay of gratification paradigm, 3- to 5-year-olds were tested on their ability to forgo a current opportunity to obtain some stickers in order to gratify their own future desires—or the current or future desires of a research assistant. Results showed that in choices involving current desires, altruistic behavior was unrelated to age. However, prudence and altruism involving future situations were correlated with one another and with age. Children under 4 years of age demonstrated significantly less future-oriented prudence than the older children (F(1,49) = 15.75; p < .001) and significantly less altruism involving future situations (F(1,49) = 33.24; p < .001). The data for the 3-year-olds, but not for the older children, also showed age-partialled correlations between the two future-oriented choice situations. These results suggest that between 3 and 4 years, children acquire the ability to deal with future-oriented situations through the development of some common mechanism which affects both future-oriented prudence and altruism.
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In lifetesting, medical follow-up, and other fields the observation of the time of occurrence of the event of interest (called a death) may be prevented for some of the items of the sample by the previous occurrence of some other event (called a loss). Losses may be either accidental or controlled, the latter resulting from a decision to terminate certain observations. In either case it is usually assumed in this paper that the lifetime (age at death) is independent of the potential loss time; in practice this assumption deserves careful scrutiny. Despite the resulting incompleteness of the data, it is desired to estimate the proportion P(t) of items in the population whose lifetimes would exceed t (in the absence of such losses), without making any assumption about the form of the function P(t). The observation for each item of a suitable initial event, marking the beginning of its lifetime, is presupposed. For random samples of size N the product-limit (PL) estimate can be defined as follows: List and label the N observed lifetimes (whether to death or loss) in order of increasing magnitude, so that one has $$0 \leqslant t_1^\prime \leqslant t_2^\prime \leqslant \cdots \leqslant t_N^\prime .$$ Then $$\hat P\left( t \right) = \Pi r\left[ {\left( {N - r} \right)/\left( {N - r + 1} \right)} \right]$$, where r assumes those values for which $$t_r^\prime \leqslant t$$ and for which $$t_r^\prime$$ measures the time to death. This estimate is the distribution, unrestricted as to form, which maximizes the likelihood of the observations. Other estimates that are discussed are the actuarial estimates (which are also products, but with the number of factors usually reduced by grouping); and reduced-sample (RS) estimates, which require that losses not be accidental, so that the limits of observation (potential loss times) are known even for those items whose deaths are observed. When no losses occur at ages less than t the estimate of P(t) in all cases reduces to the usual binomial estimate, namely, the observed proportion of survivors.
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The adaptive behavior of primates, including humans, is often mediated by temperament. Human behavior likely differs from that of other primates in part due to temperament. In the current study we compared the reaction of bonobos, chimpanzees, orangutans, and 2.5-year-old human infants to novel objects and people - as a measure of their shyness-boldness, a key temperamental trait. Human children at the age of 2.5 years avoided novelty of all kinds far more than the other ape species. This response was most similar to that seen in bonobos and least like that of chimpanzees and orangutans. This comparison represents a first step in characterizing the temperamental profiles of species in the hominoid clade, and these findings are consistent with the hypothesis that human temperament has evolved since our lineage diverged from the other apes in ways that likely have broad effects on behavior. These findings also provide new insights into how species differences in ecology may shape differences in temperament.
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Children show increasing control of emotions and behavior during their early years. Our studies suggest a shift in control from the brain's orienting network in infancy to the executive network by the age of 3-4 years. Our longitudinal study indicates that orienting influences both positive and negative affect, as measured by parent report in infancy. At 3-4 years of age, the dominant control of affect rests in a frontal brain network that involves the anterior cingulate gyrus. Connectivity of brain structures also changes from infancy to toddlerhood. Early connectivity of parietal and frontal areas is important in orienting; later connectivity involves midfrontal and anterior cingulate areas related to executive attention and self-regulation.
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Although the construct of psychopathy has received considerable attention in humans, its relevance to other animals is largely unknown. We developed a measure of psychopathy for use in chimpanzees (Pan troglodytes), the Chimpanzee Psychopathy Measure (CPM), and asked 6 raters to complete this index on 34 chimpanzees. The CPM (a) demonstrated satisfactory interrater reliability and internal consistency; (b) exhibited marginally significant sex differences (males > females); (c) correlated positively with measures of extraversion, agreeableness, and observational ratings of agonism, sexual activity, daring behaviors, teasing, silent bluff displays, and temper tantrums, and negatively with observational ratings of generosity; and (d) demonstrated incremental validity above and beyond a measure of dominance. Although further validation of the CPM is needed, these findings suggest that the psychopathy construct may be relevant to chimpanzees.
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Scientific reports of personality in nonhuman primates are now appearing with increasing frequency across a wide range of disciplines, including psychology, anthropology, endocrinology, and zoo management. To identify general patterns of research and summarize the major findings to date, we present a comprehensive review of the literature, allowing us to pinpoint the major gaps in knowledge and determine what research challenges lay ahead. An exhaustive search of five scientific databases identified 210 relevant research reports. These articles began to appear in the 1930s, but it was not until the 1980s that research on primate personality began to gather pace, with more than 100 articles published in the last decade. Our analyses of the literature indicate that some domains (e.g., sex, age, rearing conditions) are more evenly represented in the literature than are others (e.g., species, research location). Studies examining personality structure (e.g., with factor analysis) have identified personality dimensions that can be divided into 14 broad categories, with Sociability, Confidence/Aggression, and Fearfulness receiving the most research attention. Analyses of the findings pertaining to inter-rater agreement, internal consistency, test-retest reliability, generally support not only the reliability of primate personality ratings scales but also point to the need for more psychometric studies and greater consistency in how the analyses are reported. When measured at the level of broad dimensions, Extraversion and Dominance generally demonstrated the highest levels of inter-rater reliability, with weaker findings for the dimensions of Agreeableness, Emotionality, and Conscientiousness. Few studies provided data with regard to convergent and discriminant validity; Excitability and Dominance demonstrated the strongest validity coefficients when validated against relevant behavioral criterion measures. Overall, the validity data present a somewhat mixed picture, suggesting that high levels of validity are attainable, but by no means guaranteed. Discussion focuses on delineating major theoretical and empirical questions facing research and practice in primate personality.
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Two questions regarding the human mind challenge evolutionary theory: (a) What features of human psychology have changed since humans' lineage split from that of the other apes such as chimpanzees and bonobos? And (b) what was the process by which such derived psychological features evolved (e.g., what were the selection pressures)? I review some of the latest research on chimpanzee and canine psychology that allows inferences to be made regarding these questions.
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A 46-item rating scale was used to obtain personality ratings from 75 captive chimpanzees (Pan troglodytes) from 7 zoological parks. Factor analysis revealed five personality dimensions similar to those found in previous research on primate personality: Agreeableness, Dominance, Neuroticism, Extraversion and Intellect. There were significant sex and age differences in ratings on these dimensions, with males rated more highly on Dominance and older chimpanzees rated as more agreeable but less extraverted than younger chimpanzees. Interobserver agreement for most individual trait items was high, but tended to be less reliable for trait terms expressing more subtle social or cognitive abilities. Personality ratings for one zoo were found to be largely stable across a 3-year period, but highlighted the effects of environmental factors on the expression of personality in captive chimpanzees.
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The manipulative propensity and diversity of 4 members each of 10 species of primates, from lemurs to great apes to a simple inanimate object was recorded by means of a multidimensional behavioral taxonomy. The great apes as a group demonstrated a higher degree of behavioral diversity as indexed by (a) the number of combinations of body part and action used, (b) an index of diversity based on the communications technology concept of uncertainty, and (c) the proportion of the total behavior accounted for by the 30 most frequent response categories. (20 ref)
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The reactions of more than 200 zoo animals to a standardized set of novel objects were recorded and quantified. Our results indicated significant differences among various taxonomic groups, both in the quantity and form of object manipulation. Our major quantitative findings were as follows: A. Primates and Carnivores exhibited more investigatory behavior than Rodents or a group of
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Multiple measures of children's emotionality (emotional intensity and negative affectivity), regulation (including attentional and behavioral regulation and coping), and social functioning (teachers' reports of nonaggressive/socially appropriate behavior and prosocial/socially competent behavior; and parents' reports of problem behavior) were obtained for 6-8-year-olds. In addition, emotionality, attentional regulation, and coping were assessed 2 years previously. Social functioning was expected to be predicted by low negative emotionality and high levels of regulation. In general, the data supported the predictions, although the findings for parent reports of problem behavior were primarily for boys. Prediction of social functioning from measures of regulation and emotionality occurred primarily within a given context (school vs. home) rather than across contexts, even though there were relations across reporters within the school or home context. In addition, vagal tone, a marker of physiological regulation, was positively related to competent social functioning and emotionality/regulation for boys, but inversely related for girls.