Although closely linked in typically developing children, cognitive and language development may diverge in IA children – particularly when they arrive already speaking their birth language. In such cases, cognitive growth may outpace language acquisition in the new linguistic environment. This chapter examines the relevant literature, synthesizing findings from studies that illuminate these dynamics. Special attention is given to the contributions of IA individuals – especially those who enter their new homes with relative proficiency in their mother tongue – to our understanding of the interplay between language and cognition. Assessing the extent to which cognitive deficits resulting from institutional care can be mitigated, and whether such improvements are sustained over time, is essential not only for advancing theoretical knowledge of cognitive development but also for informing effective policies regarding the care of children without parental support.

In this chapter we investigate intelligence and academic achievement. In the first major section of this chapter, we focus on the concept of IQ, the so-called psychometric approach to intelligence, and some alternatives to this approach, including Robert Sternberg’s theory of adaptive intelligence and Howard Gardner’s theory of multiple intelligences. The origins and consequences of individual differences in intelligence are also examined. In the second major section of this chapter, we pay attention to the developmental, cultural, and evolutionary basis of schooling, with a particular emphasis on literacy, and numeracy, likely two of society’s most significant core academic skills.

This chapter begins by reviewing Swiss psychologist Jean Piaget’s theory. Piaget believed that the way children represent the world changes systematically between infancy and adolescence, and we describe here the main concepts and stages of his theory. We next look at theory theories of cognitive development, focusing on children’s understanding of the biological world. We conclude by looking at several expressions of symbolic functioning in children and how they change with age: symbolic play, drawing, and distinguishing between fantasy and reality.

In this chapter, we examine how children come to solve problems, remember important information, and generally learn to think on their own. Most of the research and theorizing on these topics was done following the information-processing approach of cognitive development, which uses the computer as a model for how the mind works and changes with age. After reviewing briefly some assumptions of information-processing approaches, we explore the development of self-directed thinking, problem solving, and memory. We first explore how children come to use tools as an early window to problem solving. We then investigate executive functions, the basic-level cognitive abilities that are necessary for planning and self-regulation, followed by a look at slightly higher-level cognitive processes, strategies. This is followed by an examination of a special type of problem solving, reasoning (analytic and scientific), and we conclude the chapter with a discussion of children’s memory development.

Childhood is an important time for cognitive development, during which time many factors can influence the development of complex functions like decision-making. The relationship between the HPA axis and stress reactions is of particular relevance in the development of decision-making. Fear signals activate the HPA axis, which results in cortisol production. Cortisol acts with adrenaline to form memories associated with emotional responses. This system develops early on and is dependent on exposure to stressful situations. Over activation during development, such as in cases of overexposure to stress, can result in elevated cortisol. Adverse childhood experiences (ACEs) are understood to impact a range of cognitive function; however, the relationship between negative childhood experiences and decision-making is not a linear one; research is ongoing to unravel the complexities of this relationship.

Chapter 2 explores the developmental psychology of metaphor and its significance for illness experience. While semiotics of medicine implies a simple link between physiological processes and symptom reports, illness experience is articulated through metaphors that are grounded in bodily experience, social interaction, discourse, and cultural practices. Bodily grounding of metaphor is based on sensorimotor equivalences, as seen early in development in synesthesia and cross-modal analogies. Social grounding resides in the pragmatics of language in which context and goals depend on social roles, norms, and cultural meaning. Despite this, metaphors allow for creative play by requiring only piecemeal correspondences to the world through ostension. The meaning of metaphors is then found not in representation but in presentation. Clinical examples illustrate a patient on dialysis refusing a blood transfusion and a woman with medically unexplained floating sensations, showing how a semantics of metaphor can clarify the tensions between the essential irrationality of illness experience and the biomedical presumption of rationality in normative accounts of illness cognition and behavior.

Owners generally get to decide what happens to their property, and this is reflected in legal discussions of property rights and in how children and adults view ownership. Owners’ control over property fits with the idea that ownership serves to reduce conflicts over resources. This chapter first briefly reviews experimental research that fits with this side of ownership. However, the chapter then reviews ways that ownership can take control away from owners. One line of research work shows that children and adults think that nonowners are sometimes allowed to access and even modify property without the owner’s permission. A second line of research shows that whereas people normally have some choice in acquiring ownership or giving it up, people sometimes are viewed as acquiring and retaining ownership even when they do not want to.

I focus on how, for me, big questions such as, “How can we tell whether something is true?” were funneled by haphazard influences into specific interests. Classes on logic got me interested in the origins of concepts. Contact with Piaget’s theory of concept acquisition added a developmental dimension. Wondering about the meaning of words led to the problems of opaque contexts like belief reports. A brush with artificial intelligence made me focus on the distinction between implicit and explicit mental representations and consciousness. My thesis supervisor’s expertise in game theory led me to explore children’s perspective-taking. Work with Heinz Wimmer on the false belief task got me firmly entrenched in theory of mind research, focusing on simulation theory as its main opponent. And to get beyond documenting children’s flourishing achievements I turned to mental files theory to understand how perspectival thinking grows from our basic ability to think about objects.

I have always been interested in research that was relevant to real life and the real world. I was never interested in phenomena that were confined to behavior in a laboratory. My research ended up connecting not just with other people’s lives, but with my own life. That is, my research influenced my life; and my life influenced my research. The latter was evident in my research on the development of language and communication in children, chimpanzees, and bonobos. The former was evident in my COVID research where I drew upon my longitudinal study of a Maya community to realize during the pandemic – and empirically demonstrate – that parenting, child behavior, adult activities, and values in a rural subsistence ecology are quickly revived in modern human beings when such responses are needed to adapt to survival threat and a contraction of the social world. Those findings, in turn, have reinforced my focus on the dynamic interaction of social change, cultural evolution, and human development.

Chapter 1 provides an overview of screen time concerns reported in the media and research, with consideration of relevant learning and interaction theories which indicate that face-to-face social interaction, talk and play are essential for the linguistic and cognitive development of children. This chapter also revisits the fundamental multimodality of face-to-face interaction. The shift from face-to-face to online multimodal interaction therefore requires users to make complex linguistic and interactional adaptations to be able to achieve understanding and affiliation with interlocutors in online contexts, as occurred with the advent of the telephone. This is especially true of the most common form of online interaction, text chat, which is a unique hybrid form of social written interaction, with its own specific affordances and constraints for children’s social and linguistic development. This chapter presents key interactional differences between face-to-face and written online interaction, based on conversational resources available (or unavailable) to users in either setting, including videogame settings. This discussion provides a necessary basis for investigation of children’s written interaction in subsequent chapters.