Executive function involves managing ones thoughts for the purpose of which two of the following?

Executive Function

The development of EFs begins very early on in the developmental course (early indications of inhibitory control and even working memory have been found in infancy), matures significantly during the preschool years, and continues to develop through adolescence and well into adulthood. Some studies suggest that secure EF may be more important than intellectual ability for academic success and have revealed that a child's ability to delay gratification early in life predicts competency, attention, self-regulation, frustration tolerance, aptitude, physical and mental health, and even substance dependency in adolescence and adulthood. Conversely, deficits in other areas of neurodevelopment, such as language development, impact EF.

Attention is far from a unitary, independent, or specific brain function. This may be best illustrated through the phenotype associated with ADHD) (seeChapter 49). Disordered attention can result from faulty mechanisms in and across subdomains of attention. These subdomains includeselective attention (ability to focus attention on a particular stimulus and to discriminate relevant from irrelevant information),divided attention (ability to orient to more than one stimulus at a given time),sustained attention (ability to maintain one's focus), andalternating attention (capacity to shift focus between stimuli).

Attention problems in children can manifest at any point, from arousal through output. Children with diminished alertness and arousal can exhibit signs of mental fatigue in a classroom or when engaged in any activity requiring sustained focus. They are apt to have difficulty allocating and sustaining their concentration, and their efforts may be erratic and unpredictable, with extreme performance inconsistency. Weaknesses of determining saliency often result in focusing on the wrong stimuli, at home, in school, and socially, and missing important information.Distractibility can take the form of listening to extraneous noises instead of a teacher, staring out the window, or constantly thinking about the future. Attention dysfunction can affect the output of work, behavior, and social activity. It is important to appreciate that most children with attentional dysfunction also harbor other forms of neurodevelopmental dysfunction that can be associated with academic disorders (with some estimates suggesting up to 60% comorbidity).

Inhibitory control (IC) can be described as one's ability to restrain, resist, and not act (cognitively or behaviorally/emotionally) on a thought. IC may also be seen as one's ability to stop thoughts or ongoing actions. Deficits in this behavioral/impulse regulation mechanism are a core feature of thecombined orhyperactive impulsive presentation of ADHD and have a significant adverse impact on a child's overall functioning. In everyday settings, children with weak IC may exhibit difficulties with self-control and self-monitoring of their behavior and output (e.g., impulsivity), may not recognize their own errors or mistakes, and often act prematurely and without consideration of the potential consequences of their actions. In the social context, disinhibited children may interrupt others and demonstrate other impulsive behaviors that often interfere with interpersonal relationships. The indirect consequences of poor IC often lead to challenges with behavior, emotional, and academic functioning and social interaction (Table 48.1).

Abstract

Executive functions (EFs) include high-order cognitive abilities such as working memory, inhibitory control, cognitive flexibility, planning, reasoning, and problem solving. EFs enable humans to achieve goals, adapt to novel everyday life situations, and manage social interactions. Traditionally EFs have been associated with frontal lobe functioning. More recent evidence shows that posterior and subcortical regions also play a crucial role in EF processing, especially in the integration of sensory information and emotion. This chapter reviews the variety of EFs and their neural underpinning, based on lesion mapping and neuroimaging studies, as well as the evidence for rehabilitation interventions, neuropsychological assessment based on standard and ecologically valid tests, development, and genetic predisposition for recovery of executive functions after brain injury. Taken together, the EFs are critical for unique human abilities and more careful analyses of their subcomponents may help the development of targeted translational interventions to improve them.

Abstract

Executive functions include initiation, inhibition, mental flexibility, novel problem solving, planning, emotion regulation, and self-awareness. These cognitive functions are necessary for goal-directed behavior. Frontal cortical damage has come to be viewed as sufficient to lead to executive dysfunction but not necessary in causing it. There are a number of standardized psychological tests to assess deficits in executive function, although the structured nature of the neuropsychological assessment process may obscure deficits that are apparent in daily life. Recovery and rehabilitation after frontal lobe injuries is often incomplete and may lead to persistent impairment in personal, social, and occupational functioning.

Abstract

First, executive functions are defined. Then the development of executive functions in children, from infancy to 10–11 years of age, is briefly described. The relation between the speed of processing and the development of executive functions is addressed. Finally, tools and pointers for evaluating executive functioning in younger and older children are discussed. A cautionary note is sounded, in that almost no executive function measure requires only one executive function. A child might fail a working memory task because of problems with inhibitory control (not working memory), fail an inhibitory control task because of working memory problems, or fail a cognitive flexibility, planning, or reasoning task because of problems with inhibitory control or working memory.

Teaching Procedures

The procedures used to teach executive functions are the same procedures that are used to teach any other skills; they are the procedures derived from the principles of learning and motivation from ABA. Since Chapter 4 describes these procedures in detail, we will not do so here. However, three particular procedures are critical enough to teaching EF skills that they deserve to be pointed out. First, all higher order skills, including EF skills, should be taught using multiple exemplar training, not rote or repetitive learning. The reason for this is that EF skills are not particular behaviors that need to be performed at particular times. Instead, EF skills are overarching, flexible repertoires of behavior that can be applied in virtually any situation in one’s life. For example, calling a car a “car” (i.e., labeling or tacting) is a behavior that only needs to happen in the presence of cars. Inhibiting onself from doing something regrettable (an EF skill) is a skill that, by definition, the child needs to be able to apply in new situations, in the moment, without any prior training or rehearsal in that particular situation. By definition, EF skills are generalized behavior; they cannot be memorized. Therefore, training across multiple exemplars, settings, and people is always critical. For a helpful list of exemplars to teach for each lesson, see the EF domain of the Skills® curriculum (www .skillsforautism.com; see Chapter 26). Second, task analysis and chaining are particularly useful for EF skills (as we will describe below) because many of them tend to be long and complex. Finally, behavioral skills training (see Chapter 4) deserves special mention because it, too, is highly useful for teaching EF skills.

Definitional Issues

Before we discuss the general structure of EF, a word is warranted about how EF is defined here, and even how we use the term “executive function”. “Executive function” is the most common term used in the research literature for the construct we are describing. Yet, EF sometimes goes by other names, such as “executive control” and “cognitive control” (Diamond, 2013; Espy, 2016). Unless otherwise specified by authors, these terms can be considered synonymous.

There is sometimes a tendency in the developmental literature to blur the distinctions among related concepts, however. This has led to calls for conceptual clarity for the constructs of EF, self-regulation, and effortful control (Liew, 2012; McClelland and Cameron, 2012; Zhou et al., 2012). Many researchers use these terms interchangeably, leading to conceptual conundrums and debate over underlying components (McClelland and Cameron, 2012). We agree that clarity is warranted and emphasize that we view EF, self-regulation, and effortful control as sharing some neurological underpinnings. Each of the three constructs involves some aspect of frontal lobe functioning (Diamond, 2013; Fisk and Holmboe, 2019) and each highlights the critical nature of attentional processes (Posner et al., 2012). Thus, these constructs are both overlapping and separable. The definition of EF and its underlying components used here aligns with traditional definitions of EF from the adult research literature.

Fluency

Fluency tasks have more recently been thought of as measures of executive function, as they require organizational and planning strategies. The goal of fluency tasks is to spontaneously produce the maximum number of responses without repetitions or violating the rules of the task. Verbal fluency is measured by the number of words produced in a certain time period. Common instructions for verbal fluency tasks utilize semantic or phonemic fluency. The executive aspects are required to ensure that words are not repeated and that the rules are constantly being monitored. The number of errors made or the number of intrusions within the given time period also illustrate inhibitory control.

Risks and Vulnerabilities

Complementary theories have been advanced to explain the apparent shortcomings in executive function that can occur in adolescence. Each of these theories is based on circumstantial evidence gleaned from brain imaging studies of children, adolescents, and adults, that focus either on general aspects of maturation in and across different parts of the brain or on brain images collected while participants across the age range from childhood to adulthood perform cognitively or emotionally challenging tasks.

The first of these theories involves the observation that while ‘top-down’ control is indeed improving steadily from childhood through adulthood, concurrent with development of the neural networks that support these skills, ‘bottom-up’ influences on the regulation of goal-directed behavior experience a surge of activity with the onset of puberty. Compared to children and adults, adolescents show heightened activation of the amygdala to emotional stimuli and heightened reactivity to potentially rewarding situations that is mediated through the nucleus accumbens and ventral tegmental areas of the brain. This means that adolescents are more inclined to respond to the emotional content and salience of situations, be it positive or negative, than either children or adults; resulting at times in an imbalance between ‘top-down’ and ‘bottom-up’ influences on behavioral regulation, such that the latter can prevail in decision-making. This creates fertile circumstances for impulsive responses that are guided more by emotions than by thoughtfulness. Furthermore, this heightened limbic network reactivity to emotional salience occurs in the context of a partial, transient decline in top-down control processes related to the increases in synaptic density and gray matter that occur with the onset of puberty. This imbalance gradually resolves as the maturational processes of synaptic pruning and myelination restore functionality, and promote connectivity and integration of functioning, until adult levels are ultimately attained.

The second, complementary, explanatory theory for the poor decision-making sometimes noted in the behavior of adolescents, particularly under circumstances of high emotional arousal, is predicated on observations that integration of complex meta-cognitive skills and the networks that support them is still incomplete at this stage of development. In the face of emotionally challenging tasks, for example, healthy adults recruit an extensive array of well-connected regions from both the fronto-parietal and cingulo-opercular networks in order to manage input arriving from limbic regions. The involvement of the cingulo-opercular network in particular renders these processes efficient and rapid, given its structural and functional interposition and integrative role between the front-parietal and limbic networks. By contrast, adolescents do not show such well-distributed integration across the fronto-parietal and cingulo-opercular networks in emotionally arousing situations. They do not consistently recruit cingulo-opercular regions. Instead, they rely more heavily on fronto-parietal regions to directly manage limbic input, an inherently slower and less efficient means of managing emotional arousal. The resulting delays in the interposition of top-down control means that emotionally guided behavior is more likely to break through under circumstances of high affective arousal.

If we return now to the scenario of the two friends arguing, applying these explanatory theories, we can better imagine how the argument, instead of being constructively resolved, could turn sour in various ways. The prospect of ‘winning’ the argument could result in poorly managed arousal emanating from reward circuits that promote exuberant, impulsive behaviors and utterances; while exaggerated emotions related to feelings and perceptions of being insulted or threatened, and subsequent overarousal of the amygdala, could lead to unchecked reactivity in the form of aggression or hostility, either verbal or physical. In each instance, delay in the interposition of top-down control means that any heightened emotional arousal could more easily result in a variety of impulsive, regrettable behaviors on the part of either participant.

Now with some underlying bases for beginning to understand the variations in self-regulatory capacities often observed during adolescence, it is not so difficult to go from the scenario of our two peers in an argument, to more serious risky behaviors that adolescents frequently engage in; including experimentation with alcohol and illicit drugs, as well as unprotected sexual activity, with its own attendant risks of sexually transmitted diseases and unwanted pregnancy. In both cases, based on the concerted workings of the two theories presented earlier, when these behaviors do occur, it is presumed that emotionally guided choices, which condition the perception of risk as well, prevail because of the salience of the behaviors and perceived outcomes leading to intense activation of the limbic network. This coupled with delay in the interposition of cognitive control emanating from the fronto-parietal and cingulo-opercular networks that could inhibit such behaviors a priori and then promote the formulation and implementation of more adaptive responses, enhances the likelihood that such risk-taking behaviors would occur.

What Are Executive Functions?

Executive functions are complex, higher order processes moderated primarily by the frontal lobe, specifically the prefrontal cortex. The complexity of executive function has made a universally accepted definition elusive, but attention (focusing on relevant information and ignoring distractors), working memory (maintaining information until execution), and motor planning (goal-directed motor planning and programming) are generally considered key executive functions. Executive functions influence social, emotional, intellectual, and organizational aspects of one’s life. Life can be devastated when executive functions are disrupted. Unfortunately, such disruptions occur in many human disorders.

Abstract

Executive function (EF) refers to the collection of cognitive skills (inhibition, working memory updating, task-set switching, attention) that give rise to goal-directed behaviour. EF undergoes rapid changes from birth to age 5. Changes in EF are tied to changes in frontal cortex function and how frontal cortex interacts with posterior brain regions. Basic inhibition and attention skills emerge during infancy which lay the foundation for higher-level cognitive control during toddlerhood and early childhood. Measures of EF during early childhood are predictive of various quality of life measures in adulthood, suggesting that EF is a central aspect of cognition.