Kelsey E. Woods, Christina M. Danko, and Andrea Chronis-Tuscano
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by developmentally inappropriate levels of hyperactivity, impulsivity, and/or inattention. ADHD is chronic, may persist into adulthood, and is associated with impairment in social and academic/work domains across the lifespan. Children and adolescents with ADHD often present with executive function deficits and emotion dysregulation, and these deficits may increase impairment and risk for co-occurring disorders. The etiology of ADHD is not yet understood, though research suggests that biological and environmental factors (e.g., family, community) contribute to its development and course. It should be noted that ADHD commonly co-occurs with additional psychiatric disorders, such as oppositional defiant disorder (ODD), conduct disorder (CD), and major depressive disorder.
Evidence-based assessment of ADHD requires information from multiple informants using multiple assessment methods to determine the presence of ADHD symptoms across settings and any co-occurring disorders. The evidence-based treatment options for ADHD are manifold. Pharmacotherapy for ADHD is common, although numerous behavioral interventions are also effective. Stimulant medications are commonly prescribed and are typically effective in ameliorating core ADHD symptoms. There is also evidence that the nonstimulant medication atomoxetine substantially decreases the symptoms of ADHD. Importantly, medication therapy works to reduce symptoms but typically does not alleviate the impairments associated with the disorder. Combined medication and behavioral interventions are more likely to reduce impairments and normalize behavior.
Hana D’Souza, Jamie Edgin, and Annette Karmiloff-Smith
Down syndrome (DS; trisomy 21) is the most common genetic disorder associated with intellectual disability. It occurs in one out of every 700 to 1,000 live births. DS is caused by trisomy of human chromosome 21, which results in the altered expression of over 300 genes. This neurodevelopmental syndrome is characterized by distinctive facial dysmorphology and an uneven cognitive phenotype including relative strengths and weaknesses. Relative strengths include visual processing, receptive vocabulary, and social-emotional functioning (though performance in these domains generally falls below the level expected for typically developing individuals). Relative weaknesses include verbal working memory, expressive language, and motor ability. However, the phenotype of individuals with DS is far from homogeneous, and a wide range of individual differences is present at every level of description. On the genetic level, the trisomy can occur through different mechanisms at distinct developmental time points, and the expression of trisomy 21 may be modulated by different genes across individuals. On the level of the brain, individual differences in brain structure and/or function correlate with variation in cognition and behavior, including communication skills. Large individual differences can also be observed on the cognitive level. For example, while some toddlers with DS are nonverbal, others reach expressive vocabulary levels close to those of typically developing children. A wide range of individual differences has also been reported in other areas, including the motor domain, sleep, parent-child interaction, and medical and psychiatric comorbidities.
In order to understand a neurodevelopmental syndrome such as DS, it is crucial to consider individual variations at multiple levels of description and the interactions between them over developmental time. A more complex, dynamic view that goes beyond a description of DS as a homogenous group is thus required.
Psychoanalyst Erik Erikson was the first professional to describe and use the concept of ego identity in his writings on what constitutes healthy personality development for every individual over the course of the life span. Basic to Erikson’s view, as well as those of many later identity writers, is the understanding that identity enables one to move with purpose and direction in life, and with a sense of inner sameness and continuity over time and place. Erikson considered identity to be psychosocial in nature, formed by the intersection of individual biological and psychological capacities in combination with the opportunities and supports offered by one’s social context. Identity normally becomes a central issue of concern during adolescence, when decisions about future vocational, ideological, and relational issues need to be addressed; however, these key identity concerns often demand further reflection and revision during different phases of adult life as well. Identity, thus, is not something that one resolves once and for all at the end of adolescence, but rather identity may continue to evolve and change over the course of adult life too.
Following Erikson’s initial writings, subsequent theorists have laid different emphases on the role of the individual and the role of society in the identity formation process. One very popular elaboration of Erikson’s own writings on identity that retains a psychosocial focus is the identity status model of James Marcia. While Erikson had described one’s identity resolution as lying somewhere on a continuum between identity achievement and role confusion (and optimally located nearer the achievement end of the spectrum), Marcia defined four very different means by which one may approach identity-defining decisions: identity achievement (commitment following exploration), moratorium (exploration in process), foreclosure (commitment without exploration), and diffusion (no commitment with little or no exploration). These four approaches (or identity statuses) have, over many decades, been the focus of over 1,000 theoretical and research studies that have examined identity status antecedents, behavioral consequences, associated personality characteristics, patterns of interpersonal relations, and developmental forms of movement over time. A further field of study has focused on the implications for intervention that each identity status holds. Current research seeks both to refine the identity statuses and explore their dimensions further through narrative analysis.
Deborah M. Capaldi, David C. R. Kerr, and Stacey S. Tiberio
Intergenerational studies are key to informing research, preventive intervention, and policy regarding family influences on healthy development and maladjustment. Continuities in family socialization and contextual risks across generations, as well as genetic factors, are associated with the development of psychopathology—including externalizing problems in children—and with intergenerational associations in the use of marijuana, alcohol, tobacco, and other drugs; these continuities are reflected in the low-to-moderate associations generally found in prospective studies. Until recent years, estimates of intergenerational continuities in problem behaviors and the processes explaining such associations (e.g., parenting behaviors) have been based largely on retrospective reports by adults about their own parents’ behaviors. Now there are some long-term prospective studies spanning as many as 30 years that can assess linkages between behaviors in one generation and the next. Whereas such studies have considerable design and implementation challenges, and are very expensive, it is of critical importance to examine the magnitude of associations of behaviors across generations. For example, a modest association across generations suggests either that genetic factors have a limited influence on that behavior or that they are subject to considerable moderation by environmental factors. These prospective studies relate to theoretical developments regarding intergenerational influences that are reviewed—for example, individual differences in genetic sensitivity to environmental influences. The theoretical approach employed in the Oregon Youth Study—Three Generation Study is a Dynamic Developmental Systems (DDS) model of continuous feedback across systems throughout development. A new hypothesis encompassed by DDS is developmental congruence of intergenerational associations in problem behaviors. As used in geometry, congruence refers to figures of a similar shape and size. This term has been adapted to refer to the expectation that ages of onset and patterns of growth in key behaviors will show similarity across generations. This is based on the theory that genetic and temperamental factors increase an individual’s risk when these factors are expressed at sensitive developmental periods. Thus, the timing of these manifestations (e.g., susceptibility to deviant peer influences) is expected to be similar across generations. Developmental similarity is also likely due to continuities in social-risk context and family mechanisms, such as parenting.
Erica H. Wojcik, Irene de la Cruz-Pavía, and Janet F. Werker
Language is a structured form of communication that is unique to humans. Within the first few years of life, typically developing children can understand and produce full sentences in their native language or languages. For centuries, philosophers, psychologists, and linguists have debated how we acquire language with such ease and speed. Central to this debate has been whether the learning process is driven by innate capacities or information in the environment. In the field of psychology, researchers have moved beyond this dichotomy to examine how perceptual and cognitive biases may guide input-driven learning and how these biases may change with experience. There is evidence that this integration permeates the learning and development of all aspects of language—from sounds (phonology), to the meanings of words (lexical-semantics), to the forms of words and the structure of sentences (morphosyntax). For example, in the area of phonology, newborns’ bias to attend to speech over other signals facilitates early learning of the prosodic and phonemic properties of their native language(s). In the area of lexical-semantics, infants’ bias to attend to novelty aids in mapping new words to their referents. In morphosyntax, infants’ sensitivity to vowels, repetition, and phrase edges guides statistical learning. In each of these areas, too, new biases come into play throughout development, as infants gain more knowledge about their native language(s).
Scarcity is typically defined as the condition of having insufficient resources to cope with demands. This condition has important psychological implications. That is, it presents significant challenges to the human cognitive system. For example, having limited financial resources requires the meticulous calculation of expenses with respect to a budget. Likewise, having limited time requires the stringent management of schedules with respect to a deadline. As such, scarcity consumes cognitive resources such as attention, working memory, and executive control, and elicits a range of predictable and even counter-productive cognitive and behavioral responses as a result. According to a series of recent studies, scarcity focuses the attention on the problem at hand. This focus of attention facilitates performance by enhancing cognitive processing of information relevant to the problem, increasing the efficiency of resource use, and stabilizing the perception of value. Such prioritization of the problem at hand may seem advantageous, but it can lead to the neglect of other information that also needs attention. For example, scarcity causes myopic and impulsive behavior, prioritizing short-term benefits over long-term gains. Ironically, scarcity can also result in a failure to notice beneficial information in the environment that alleviates the condition of scarcity. More detrimentally, scarcity directly impairs cognitive function, which can lead to suboptimal decisions and choices that exacerbate the condition of scarcity.
These findings provide new insights on what scarcity means. It means not only making tradeoffs about physical resources (e.g., if I buy X, I cannot buy Y), but also making attentional tradeoffs (e.g., if I focus on X, I cannot focus on Y). The shortage of physical resources under scarcity is accompanied by a concurrent deficit of cognitive resources (e.g., attention, executive control). The cognitive deficits under scarcity are particularly problematic because they impair performance and lead to counter-productive behaviors that deepen the cycle of scarcity. In addition, people under financial scarcity suffer from stigmas and stereotypes associated with poverty. These social perceptions of poverty further burden the mind of the poor by consuming their cognitive resources, weakening performance in the poor. Understanding the cognitive and behavioral responses to scarcity provides new explanations as to why the poor remain poor, identifies the psychological causes of scarcity, and illuminates potential interventions to stop the cycle of scarcity. These insights have important implications for the design and implementation of policies and services targeting the populations under scarcity.
Laurence B. Leonard
Children with specific language impairment (SLI) have a significant deficit in their ability to acquire language that cannot be attributed to intellectual disability, neurological damage, hearing loss, or a diagnosis of autism. These deficits can be long-standing, and adversely affect other aspects of the affected individual’s life. There seems to be a genetic component to SLI, but the disorder is not likely to be traced to a single gene. The problem appears to be universal, but symptoms vary depending on the language being learned. Current attempts to account for SLI have increased our understanding of the most salient symptoms of the disorder, but a full understanding of SLI is not yet within reach.