Megan S. Barker, Emily C. Gibson, and Gail A. Robinson
The term “acquired brain injury” refers to any type of brain damage that occurs after birth. Two main types of acquired brain injury are stroke and traumatic brain injury (TBI). A stroke occurs when there is a blockage or bleed in the vascular system of the brain, while a TBI results from an external force to the head. Older adults are at a higher risk of both stroke and TBI; thus, overall incidence is increasing as the proportion of older adults in the population is growing. Stroke and TBI result in immediate and long-term cognitive changes. Impairments in the domains of language, attention, memory, executive functions, perception, and social cognition have been documented following stroke and TBI. However, strokes tend to cause focal or selective cognitive disorders, while cognitive deficits following TBI are widespread and can be generalized. Individuals who have suffered a stroke or TBI may also experience psychosocial changes; for example, symptoms of depression and anxiety are common. Functional outcomes, including independence in activities, are varied and are associated with a range of factors including age, injury severity, cognitive disorders, and psychosocial factors. To achieve optimal outcomes for individuals following stroke and TBI, and to reduce the impact of the injury on everyday functioning, a multidisciplinary rehabilitation process is recommended.
Aidan Moran and John Toner
We are constantly bombarded by information. Therefore, during every waking moment of our lives, we face decisions about which stimuli to prioritize and which ones to ignore. To complicate matters, the information that clamors for our attention includes not only events that occur in the world around us but also experiences that originate in the subjective domain of our own thoughts and feelings. The end result is that our minds can consciously attend to only a fraction of the rich kaleidoscope of information and experiences available to us from our senses, thoughts, memories, and imagination. Attentional processes such as “concentration,” or the ability to focus on the task at hand while ignoring distractions, are crucial for success in sport and other domains of skilled performance. To illustrate, Venus Williams, one of the greatest tennis players of all time, proclaimed that “for the players it is complete and pure focus. You don’t see anything or hear anything except the ball and what’s going on in your head.” For psychological scientists, concentration resembles a mental spotlight (like the head-mounted torch that miners and divers wear in dark environments) that illuminates targets located either in the external world around us or in the internal world of our subjective experiences. A major advantage of this spotlight metaphor is that it shows us that concentration is never “lost”—although it can be diverted to targets (whether in the external world or inside our heads) that are irrelevant to the task at hand. Research on attentional processes in sport and performance has been conducted in cognitive psychology (the study of how the mind works), cognitive sport psychology (the study of mental processes in athletes), and cognitive neuroscience (the study of how brain systems give rise to mental processes). From this research, advances have been made both in measuring attentional processes and in understanding their significance in sport and performance settings. For example, pupillometry, or the study of changes in pupil diameter as a function of cognitive processing, has been used as an objective index of attentional effort among skilled performers such as musicians and equestrian athletes. Next, research suggests that a heightened state of concentration (i.e., total absorption in the task at hand) is crucial to the genesis of “flow” states (i.e., rare and elusive moments when everything seems to come together for the performer) and optimal performance in athletes. More recently, studies have shown that brief mindfulness intervention programs, where people are trained to attend non-judgmentally to their own thoughts, feelings, and sensations, offer promise in the quest to enhance attentional skills in elite athletes. By contrast, anxiety has been shown to divert skilled performers’ attention to task-irrelevant information—sometimes triggering “choking” behavior or the sudden and significant deterioration of skilled performance. Finally, concentration strategies such as “trigger words” (i.e., the use of short, vivid, and positively phrased verbal reminders such as “this ball now”) are known to improve athletes’ ability to focus on a specific target or to execute skilled actions successfully.
Ye In (Jane) Hwang and Julian Trollor
Autism spectrum disorder (ASD), or autism, is a neurodevelopmental disorder that is typically recognized and diagnosed in childhood. There is no established biological marker for autism; rather, the diagnosis is made based on observation of behavioral traits, including (a) persistent deficits in social interaction and communication, and (b) restricted, repetitive patterns of behavior, interests, or activities. Because autism is a spectrum disorder, autistic individuals are a highly heterogeneous group and differ widely in the presentation and severity of their symptoms. The established prevalence of ASD is approximately 1% of the population.
Information about autism in adulthood is limited; most of the literature examines childhood and adolescence. While the term “later life” has traditionally been associated with those over the age of 65, a dire lack of understanding exists for those on the autism spectrum beyond early adulthood.
Individuals remain on the spectrum into later life, though some mild improvements in symptoms are observed over time. Autistic adults experience high levels of physical and mental health comorbidities. Rates of participation in employment and education are also lower than that of the general population. Quality of life is reportedly poorer for autistic adults than for nonautistic peers, though this is not affected by age. More robust studies of the health, well-being, and needs of autistic adults are needed, especially qualitative investigations of adulthood and aging and longitudinal studies of development over the lifespan.
Anne Josephine Dutt, Hans-Werner Wahl, and Manfred Diehl
The term Awareness of Aging (AoA) incorporates all aspects of individuals’ perceptions, behavioral experiences, and subjective interpretations related to their process of growing older. In this regard, AoA goes beyond objective descriptions of the aging process, such as calendar age or biological age. Commonly used AoA constructs referring to the ongoing experience of the aging process encompass concepts such as subjective age, attitudes toward one’s own aging, self-perceptions of aging, and awareness of age-related change. AoA also incorporates elements that are more pre-conscious in nature, such as age stereotypes and culturally held notions about the aging process. Despite their theoretically broad common foundation, AoA constructs differ according to their specific frames of reference, such as whether and how they take into account the multidimensionality and multi-directionality of development. Examining the existing body of empirical work identifies several antecedents of AoA, such as sociodemographic “background” variables, physical health and physical functioning, cognition, psychological well-being and mental health, psychological variables (e.g., personality, anxiety), and life events. In general, more positive manifestations on these variables are accompanied by a more positive perception and evaluation of the aging process. Moreover, AoA is longitudinally linked to important developmental outcomes, such as health, cognition, subjective well-being, and mortality. Overall, the study of AoA has developed as a promising area of psychological aging research that has grown in its conceptual and empirical rigor during recent years.
Karen Z. H. Li, Halina Bruce, and Rachel Downey
Research on the interplay of cognition and mobility in old age is inherently multidisciplinary, informed by findings from life span developmental psychology, kinesiology, cognitive neuroscience, and rehabilitation sciences. Early observational work revealed strong connections between sensory and sensorimotor performance with measures of intellectual functioning. Subsequent work has revealed more specific links between measures of cognitive control and gait quality. Convergent evidence for the interdependence of cognition and mobility is seen in patient studies, wherein cognitive impairment is associated with increased frequency and risk of falling. Even in cross-sectional studies involving healthy young and older adults, the effects of aging on postural control and gait are commonly exacerbated when participants perform a motor task with a concurrent cognitive load. This motor-cognitive dual-task method assumes that cognitive and motor domains compete for common capacity, and that older adults recruit more cognitive capacity than young adults to support gait and posture.
Neuroimaging techniques such as magnetic resonance imaging (MRI) have revealed associations between measures of mobility (e.g., gait velocity and postural control) and measures of brain health (e.g., gray matter volumes, cortical thickness, white matter integrity, and functional connectivity). The brain regions most often associated with aging and mobility also appear to subserve high-level cognitive functions such as executive control, attention, and working memory (e.g., dorsolateral prefrontal cortex, anterior cingulate). Portable functional neuroimaging has allowed for the examination of neural functioning during real-time walking, often in conjunction with detailed spatiotemporal measures of gait. A more recent strategy that addresses the interdependence of cognitive and motor processes in old age is cognitive remediation. Cognitive training has yielded promising improvements in balance, walking, and overall mobility status in healthy older adults, and those with age-related neurodegenerative conditions such as Parkinson’s Disease.
Skylar M. Brannon and Bertram Gawronski
The desire to maintain consistency between cognitions has been recognized by many psychologists as an important human motive. Research on this topic has been highly influential in a variety of areas of social cognition, including attitudes, person perception, prejudice and stereotyping, and self-evaluation. In his seminal work on cognitive dissonance, Leon Festinger noted that inconsistencies between cognitions result in negative affect. Further, he argued that the motivation to maintain consistency is a basic motive that is intrinsically important. Subsequent theorists posed revisions to Festinger’s original theory, suggesting that consistency is only important to the extent that it allows one to maintain a desired self-view or to communicate traits to others. According to these theorists, the motivation to maintain consistency serves as a means toward a superordinate motive, not as an end in itself. Building on this argument, more recent perspectives suggest that consistency is important for the execution of context-appropriate action and the acquisition and validation of knowledge.
Several important lines of research grew out of the idea that cognitive consistency plays a central role in social information processing. One dominant line of research has aimed toward understanding how people deal with inconsistencies between their attitudes and their behaviors. Other research has investigated how individuals maintain their beliefs either by (1) avoiding exposure to contradictory information or (2) engaging in cognitive processes aimed toward reconciling an inconsistency after being exposed to contradictory information. Cognitive consistency perspectives have also been leveraged to understand (1) the conditions under which explicit and implicit evaluations correlate with one another, (2) when change in one type of evaluation corresponds with change in the other, and (3) the roles of distinct types of consistency principles underlying explicit and implicit evaluations.
Expanding on these works, newer lines of research have provided important revisions and extensions to early research on cognitive consistency, focusing on (1) the identification of inconsistency, (2) the elicitation of negative affect in response to inconsistency, and (3) behavioral responses aimed to restore inconsistency or mitigate the negative feelings arising from inconsistency. For example, some research has suggested that, instead of following the rules of formal logic, perceptions of (in)consistency are driven by “psycho-logic” in that individuals may perceive inconsistency when there is logical consistency, and vice versa. Further, reconciling conflicting research on the affective responses to inconsistency, recent work suggests that all inconsistencies first elicit negative affect, but immediate affective reactions may change in line with the hedonic experience of the event when an individual has time to make sense of the inconsistency. Finally, new frameworks have been proposed to unite a broad range of phenomena under one unifying umbrella, using the concept of cognitive consistency as a common denominator.
Aleksandra Kudlicka and Linda Clare
The number of people living with dementia is growing, and with limited pharmacological treatment options the importance of psychosocial interventions is increasingly recognized. Cognitive rehabilitation is particularly well placed to address the needs of people living with mild and moderate dementia and their family supporters, as it offers a range of tools to tackle the complexity of the condition. It utilizes powerful approaches of problem solving and goal setting combined with evidence-based rehabilitative techniques for managing cognitive impairments. It also incorporates strategies to address emotional and motivational aspects of dementia that may affect a person’s well-being. It is provided on an individual basis, usually in people’s homes, making it directly applicable to everyday life. It is also genuinely person-centered and flexible as the therapy goals are agreed in a collaborative process between the therapist, person with dementia, and family members. Cognitive rehabilitation does not claim to address underlying pathology, but instead focuses on a person’s functional ability and enjoyment of life.
Evidence for effectiveness of cognitive rehabilitation in the context of mild and moderate dementia, mostly Alzheimer’s disease (AD), is gradually accumulating with a number of randomized control trials demonstrating that people with mild and moderate dementia can significantly improve their functioning in targeted areas. For example, the GREAT trial with 475 people with mild to moderate Alzheimer’s, vascular, and mixed dementia completed in 2017 in the United Kingdom demonstrated that cognitive rehabilitation improves everyday functioning in relation to individual therapy goals.
There is a growing interest in cognitive rehabilitation and the focus shifts to extending evidence to less-common forms of dementia, particularly in people with non-amnestic presentation. Future efforts need to concentrate on promoting the approach and optimizing application in real-life settings with the aim of maximizing benefits for people living with dementia and their families.
Alison Chasteen, Maria Iankilevitch, Jordana Schiralli, and Veronica Bergstrom
In 2016, Statistics Canada released the results of the most recent census. For the first time ever, the proportion of Canadians aged 65-plus years surpassed the proportion aged 15 and under. The increase in the proportion of older adults was viewed as further evidence of the faster rate of aging of Canada’s population. Such demographic shifts are not unique to Canada; many industrialized nations around the world are experiencing similar changes in their populations. Increases in the older adult population in many countries might produce beneficial outcomes by increasing the potential for intergenerational contact and exposure to exemplars of successful aging. Such positive intergenerational contact could counter prevailing age stereotypes and improve intergenerational relations. On the other hand, such increases in the number of older adults could be viewed as a strain and potential threat to resources shared with younger age groups. The possibility of increased intergenerational conflict makes it more important than ever before to understand how older adults are stereotyped, how those stereotypes can produce different kinds of biased behavior toward them, and what the impact of those stereotypes are on older adults themselves.
Social-cognitive age representations are complex and multifaceted. A common stereotype applied to older people is one of warmth but incompetence, often resulting in paternalistic prejudice toward them. However, such benevolent prejudice, characterized by warm overtones, can change to hostile bias if older adults are perceived to violate prescriptive norms about age-appropriate behavior. In addition to coping with age prejudice, older adults also have to deal with the deleterious effects of negative age stereotypes on their day-to-day function. Exposure to negative aging stereotypes can worsen older adults’ cognitive performance in a number of contexts. As well, age stereotypes can be incorporated into older adults’ own views of aging, also leading to poorer outcomes for them in a variety of domains. A number of interventions to counteract the effects of negative aging stereotypes appear promising, but more work remains to be done to reduce the impact of negative aging stereotypes on daily function in later life.
Michael Cole and Martin Packer
This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Psychology. Please check back later for the full article.
There is a growing appreciation of the importance of understanding the role of culture in children’s psychological development (also called human ontogenesis). In particular, the texts of Lev Vygotsky contributed greatly to a “cultural psychology” in which the study of culture and development is seen as central. At the same time, cross-cultural research in psychology has paid growing attention to developmental issues. Although there continues to be much debate over how to define culture, it is generally agreed that different human social groups have distinct cultures. It is common to assume, in addition, that cultural differences lead to differences in the trajectories of children’s development. This is true, but it is also the case that culture is a universal requirement for development. The interdependence of human communities—which probably had its origins in collaborative hunting and cooperative childrearing—seems to have placed demands on children’s development, selecting for a sensitivity to norms and to other people’s goals and intentions. Every child is born into a family and community with a language, customs, and conventions, and in which people have institutional rights and responsibilities. These define universal requisites of human psychological development: These include the acquisition of language, the development of a social identity, the understanding of community obligations, and the ability to contribute to the reproduction of the community. An open question today is the character of the capacities that children bring to these developmental tasks: the apparently species-unique ability that has made possible vast “cumulative” societies.
Dyslexia, or a reading disability, occurs when an individual has great difficulty at the level of word reading and decoding. Comprehension of text, writing, and spelling are also affected. The diagnosis of dyslexia involves the use of reading tests, but the continuum of reading performance means that any cutoff point is arbitrary. The IQ score does not play a role in the diagnosis of dyslexia. Dyslexia is a language-based learning disability. The cognitive difficulties of dyslexics include problems with recognizing and manipulating the basic sounds in a language, language memory, and learning the sounds of letters. Dyslexia is a neurological condition with a genetic basis. There are abnormalities in the brains of dyslexic individuals. There are also differences in the electrophysiological and structural characteristics of the brains of dyslexics. Hope for dyslexia involves early detection and intervention and evidence-based instruction.
Emma V. Ward and David R. Shanks
This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Psychology. Please check back later for the full article.
It is well documented that explicit (declarative, conscious) memory declines in normal aging. Studies have shown a progressive reduction in this form of memory with age, and healthy older adults (typically aged 65+ years) usually perform worse than younger adults (typically aged 18–30 years) on laboratory tests of explicit memory such as recall and recognition. In contrast, it is less clear whether implicit (procedural, unconscious) memory declines or remains stable in normal aging. Implicit memory is evident when previous experiences affect (e.g., facilitate) performance on tasks that do not require conscious recollection of those experiences. This can manifest in rehearsed motor skills, such as playing a musical instrument, but is typically indexed in the laboratory by the greater ease with which previously studied information is processed relative to non-studied information (e.g., repetition-priming). While a vast amount of research has accumulated to suggest that implicit memory remains relatively stable over the adult life span and is similar in samples of young and older adults, other studies have, in contrast, revealed that implicit memory is subject to age-related decline. Improving methods for determining whether implicit memory declines or remains stable with age is an important goal for future research, as the conclusion not only holds fundamental implications for an aging society, but can also inform our theoretical understating of human memory systems.
DeMond M. Grant and Evan J. White
Cognitive control is the ability to direct attention and cognitive resources toward achieving one’s goals. However, research indicates that anxiety biases multiple cognitive processes, including cognitive control. This occurs in part because anxiety leads to excessive processing of threatening stimuli at the expense of ongoing activities. This enhanced processing of threat interferes with several cognitive processes, which includes how individuals view and respond to their environment. Specifically, research indicates that anxious individuals devote their attention toward threat when considering both early, automatic processes and later, sustained attention. In addition, anxiety has negative effects on working memory, which involves the ability to hold and manipulate information in one’s consciousness. Anxiety has been found to decrease the resources necessary for effective working memory performance, as well as increase the likelihood of negative information entering working memory. Finally, anxiety is characterized by focusing excessive attention on mistakes, and there is also a reduction in the cognitive control resources necessary to correct behavior. Enhancing our knowledge of how anxiety affects cognitive control has broad implications for understanding the development of anxiety disorders, as well as emerging treatments for these conditions.
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).
Markus Wettstein, Hans-Werner Wahl, and Michael Schwenk
When referring to life space, researchers usually mean the area in which individuals move in their everyday lives. Life space can be measured based on different approaches, by means of self-reports (i.e., questionnaires or diaries) or by more recent approaches of technology-based objective assessment (e.g., via Global Positioning System [GPS] devices or smartphones). Life space is an important indicator of older adults’ out-of-home mobility and is meaningfully associated with autonomy, well-being, and quality of life. Substantial relationships between life space and socio-demographic indicators, health, and cognitive abilities have been reported in previous research. Future research on life space in old age will benefit from a more comprehensive and stronger interdisciplinary perspective, from taking into account different time scales (i.e., short- and long-term variability), and from considering life space as a multidimensional measure that can be best assessed based on multi-method approaches with multiple indicators.
Nicole D. Anderson
Healthy aging is accompanied by decrements in episodic memory and working memory. Significant efforts have therefore been made to augment episodic and working memory in healthy older adults. Two principal approaches toward memory rehabilitation adults are restorative approaches and compensatory approaches. Restorative approaches aim to repair the affected memory processes by repeated, adaptive practice (i.e., the trained task becomes more difficult as participants improve), and have focused on recollection training, associative memory training, object-location memory training, and working memory training. The majority of these restorative approaches have been proved to be efficacious, that is, participants improve on the trained task, and there is considerable evidence for maintenance of training effects weeks or months after the intervention is discontinued. Transfer of restorative training approaches has been more elusive and appears limited to other tasks relying on the same domains or processes. Compensatory approaches to memory strive to bypass the impairment by teaching people mnemonic and lifestyle strategies to bolster memory performance. Specific mnemonic strategy training approaches as well as multimodal compensatory approaches that combine strategy training with counseling about other factors that affect memory (e.g., memory self-efficacy, relaxation, exercise, and cognitive and social engagement) have demonstrated that older adults can learn new mnemonics and implement them to the benefit of memory performance, and can adjust their views and expectations about their memory to better cope with the changes that occur during healthy aging. Future work should focus on identifying the personal characteristics that predict who will benefit from training and on developing objective measures of the impact of memory rehabilitation on older adults’ everyday functioning.
Christopher Hertzog and Taylor Curley
Metamemory is defined as cognitions about memory and related processes. Related terms in the literature include metacognition, self-evaluation, memory self-efficacy, executive function, self-regulation, cognitive control, and strategic behavior. Metamemory is a multidimensional construct that includes knowledge about how memory works, beliefs about memory (including beliefs about one’s own memory such as memory self-efficacy), monitoring of memory and related processes and products, and metacognitive control, in which adaptive changes in processing approaches and strategies may be contemplated if monitoring of memory processes (encoding, retention, retrieval) indicates that alternative strategies may be required. Older adults generally believe that their memory has declined and that, on average, they have less control over memory and lower memory self-efficacy than young and middle-aged adults. Many but not all aspects of online memory monitoring are well preserved in old age, such as the ability to discriminate between information that has been learned versus not learned. A major exception concerns confidence judgments concerning whether recognition memory decisions are correct; older adults are more prone to high-confidence memory errors, believing they are recognizing something they have not encountered previously. The evidence regarding metacognitive control is more mixed, with some hints that older adults do not use monitoring to adjust control behaviors (e.g., devoting more time and effort to studying items they believe have not yet been well-learned). However, any age deficits in self-regulation based on memory monitoring or adaptive strategy use can probably be addressed through instructions, practice, or training. In general, older adults seem capable of exerting metacognitive control in memory studies, although they may not necessarily do so without explicit support or prompting.
Scott P. Johnson
Visual scenes tend to be very complex: a multitude of overlapping surfaces varying in shape, color, texture, and depth relative to the observer. Yet most observers effortlessly perceive that the visual environment is composed of distinct objects, laid out across space, each with a particular shape that can be inferred from partial views and incomplete information. Moreover, observers generally expect objects to be continuous across space and time, to have a certain shape, and to be solid in three-dimensional (3D) space. The cortical visual system processes information for objects first by coding visual features, then by linking features into units, and last by interpretation of units as objects that may be recognizable or otherwise relevant to the observer. This way of conceptualizing object perception maps roughly onto processes of lower-, middle-, and higher-level visual processing that have long formed the basis for investigations of visual perception in adults, as well as theories of object perception, the ways visual deprivation reduces object perception skills, and the developmental time course of object perception in infancy.
Patrick D. Gajewski and Michael Falkenstein
Healthy aging is associated with changes in sensory, motor, cognitive, and emotional functions. Such changes depend on various factors. In particular, physical activity not only improves physical and motor but also cognitive and emotional functions. Observational (i.e., associations) and cross-sectional studies generally show a positive effect of regular physical exercise on cognition in older adults. Most longitudinal randomized controlled intervention studies also show positive effects, but the results are inconsistent due to large heterogeneity of methodological setups. Positive changes accompanying physical activity mainly impact executive functions, memory functions, and processing speed. Several factors influence the impact of physical activity on cognition, mainly the type and format of the activity. Strength training and aerobic training yield comparable but also differential benefits, and all should be used in physical activities. Also, a combination of physical activity with cognitive activity appears to enhance its effect on cognition in older age. Hence, such combined training approaches are preferable to homogeneous trainings. Studies of brain physiology changes due to physical activity show general as well as specific effects on certain brain structures and functions, particularly in the frontal cortex and the hippocampus, which are those areas most affected by advanced age. Physical activity also appears to improve cognition in patients with mild cognitive dysfunction and dementia and often ameliorates the disease symptoms. This makes physical training an important intervention for those groups of older people.
Apart from cognition, physical activity leads to improvement of emotional functions. Exercise can lead to improvement of psychological well-being in older adults. Most importantly, exercise appears to reduce symptoms of depression in seniors. In future intervention studies it should be clarified who profits most from physical activity. Further, the conditions that influence the cognitive and emotional benefits older people derive from physical activity should be investigated in more detail. Finally, measures of brain activity that can be easily applied should be included as far as possible.
Jennifer L. Etnier
There is substantial interest in identifying the behavioral means by which to improve cognitive performance. Recent research and commercial ventures have focused on cognitive training interventions, but evidence suggests that the effects of these programs are small and task-specific. Researchers have also shown interest in exploring the potential benefits of physical activity for cognitive performance. Because the effects of physical activity have been found to be small to moderate and to be more global in nature, interest in physical activity has been growing over the past several decades. Evidence regarding the efficacy of physical activity is provided through cross-sectional studies, longitudinal prospective studies, and randomized controlled trials. When reviewed meta-analytically, small-to-moderate beneficial effects are reported for children, adults, older adults, and cognitively impaired older adults, and these effects are evident for a wide range of cognitive domains, including executive function, memory, and information processing. Researchers are currently focused on identifying the mechanisms of these effects. Most of this research has been conducted using animal models, but there is a growing body of literature with humans. From this evidence, there is support for the role of changes in cerebral structure, hippocampal perfusion, and growth factors in explaining the observed benefits. Thus far, however, the literature is quite sparse, and future research is needed to clarify our understanding of the mechanisms that provide the causal link between physical activity and cognitive performance. Research is also focused on understanding how to increase the benefits by potentially combining cognitive training with physical activity and by identifying the genetic moderators of the effects. These lines of work are designed to elucidate ways of increasing the magnitude of the benefits that can be obtained. At this point in time, the evidence with respect to the potential of physical activity for benefiting cognitive performance is quite promising, but it is critical that funding agencies commit their support to the continued exploration necessary to allow us to ultimately be able to prescribe physical activity to specific individuals with the express purpose of improving cognition.
Jiaying Zhao and Brandon M. Tomm
Scarcity is the condition of having insufficient resources to cope with demands. This condition 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 systematic and even counter-productive cognitive and behavioral responses as a result. Specifically, scarcity induces an attentional focus on the problem at hand, which 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 produce undesirable consequences. For example, scarcity causes myopic and impulsive behavior, prioritizing short-term gains 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. Thus, scarcity means not only a shortage of physical resources (e.g., money or time) but also a 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 by consuming cognitive resources, weakening performance in the poor. Understanding the cognitive and behavioral responses to scarcity provides new insights into why the poor remain poor, identifying the psychological causes of scarcity, and illuminating potential interventions to stop the cycle of scarcity. These insights have important implications for the design and the implementation of policies and services targeting the populations under scarcity.