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.
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.
Benjamin T. Mast and Diana DiGasbarro
Clinicians conduct capacity evaluations to determine an older adult’s ability to make and execute a decision within key domains of functioning. Questions of capacity often arise when an older adult experiences a decline in cognitive functioning due to Alzheimer’s disease, stroke, or severe psychiatric illness, for example. Capacity is related to legal competency, and a lack of capacity may be proved by providing evidence that an older adult is unable to understand the act or decision in question; appreciate the context and consequences of the decision or act; reason about the potential harms and benefits; or express a choice. Capacity is domain-specific, time-specific, and decision-specific. Domains include financial capacity, medical treatment and research consent capacity, driving capacity, sexual consent capacity, and voting capacity. Each capacity domain encompasses activities that may vary in complexity or risk, and thus require different levels of capacity. For example, within the medical treatment consent capacity domain, an older adult may lack the capacity to consent to a complicated and risky surgical procedure while retaining the capacity to consent to a routine blood draw. Clinicians determine capacity by using a combination of tools including capacity assessment instruments, task-specific functional evaluations, interviews with the patient and family members, measures of cognitive functioning, and consideration of social, physical, and mental health factors. Extensive research has been conducted to determine the reliability and validity of a variety of capacity assessment instruments for many domains. These instruments generally assess the patient’s responses to vignettes pertaining to the domain in question, information gleaned from structured and semi-structured interviews, functional ability, or a combination of these methods. Although there is still need for more research, especially in emerging domains, capacity assessments help to protect vulnerable older adults from harm while allowing them to retain the highest possible level of autonomy.
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.
Benjamin Boller and Sylvie Belleville
Individuals with mild cognitive impairment (MCI) experience cognitive difficulties and many find themselves in a transitional stage between aging and dementia, making this population a suitable target for cognitive intervention. In MCI, not all cognitive functions are impaired and preserved functions can thus be recruited to compensate for the impact of cognitive impairment. Improving cognition may have a tremendous impact on quality of life and help delay the loss of autonomy that comes with dementia. Several studies have reported evidence of cognitive benefits following cognitive intervention in individuals with MCI. Studies that relied on training memory and attentional control have provided the most consistent evidence for cognitive gains. A few studies have investigated the neurophysiological processes by which these training effects occur. More research is needed to draw clear conclusions on the type of brain processes that are engaged in cognitive training and there are insufficient findings regarding transfer to activities of daily life. Results from recent studies using new technologies such as virtual reality provide encouraging evidence of transfer effects to real-life situations.
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.
Anthony P. Kontos and Jamie McAllister-Deitrick
Concussions affect millions of athletes of all ages each year in a variety of sports. Athletes in certain sports such as American football, ice hockey, rugby, soccer, and combative sports like boxing are at higher risk for concussion. Direct or indirect mechanical forces acting on the skull and brain cause a concussion, which is a milder form of brain injury. Conventional neuroimaging (e.g., computerized tomography [CT], magnetic resonance imaging [MRI]) for concussion is typically negative. Concussions involve both neurometabolic and subtle structural damage to the brain that results in signs (e.g., loss of consciousness [LOC], amnesia, confusion), symptoms (e.g., headache, dizziness, nausea), and functional impairment (e.g., cognitive, balance, vestibular, oculomotor). Symptoms, impairment, and recovery time following concussion can last from a few days to weeks or months, based on a variety of risk factors, including younger age, female sex, history of concussion, and history of migraine. Following a concussion, athletes may experience one or more clinical profiles, including cognitive fatigue, vestibular, oculomotor, post-traumatic migraine (PTM), mood/anxiety, and/or cervical. The heterogeneous nature of concussion warrants a comprehensive approach to assessment, including a thorough clinical examination and interview; symptom inventories; and cognitive, balance, vestibular, oculomotor, and exertion-based evaluations. Targeted treatment and rehabilitation strategies including behavior management, vestibular, vision, and exertion therapies, and in some cases medication can be effective in treating the various concussion clinical profiles. Some athletes experience persistent post-concussion symptoms (PCS) and/or psychological issues (e.g., depression, anxiety) following concussion. Following appropriate treatment and rehabilitation strategies, determination of safe return to play is predicated on being symptom-free and back to normal levels of function at rest and following exertion. Certain populations, including youth athletes, may be at a higher risk for worse impairment and prolonged recovery following concussion. It has been suggested that some athletes experience long-term effects associated with concussion including chronic traumatic encephalopathy (CTE). However, additional empirical studies on the role of concussion on CTE are needed, as CTE may have multiple causes that are unrelated to sport participation and concussion.
Philip Sayegh, David J. Moore, and Pariya Fazeli Wheeler
Since the first cluster of people with HIV was identified in 1981, significant biomedical advances, most notably the development of antiretroviral therapy (ART), have led to considerably increased life expectancy as well as a reduction in the morbidity and mortality associated with HIV/AIDS. As a result, HIV/AIDS is no longer considered a terminal illness, but rather a chronic illness, and many persons living with HIV/AIDS are beginning to enter or have already reached later life. In fact, Americans ages 50 years and older comprise approximately half of all individuals with HIV/AIDS and represent the most rapidly growing subpopulation of persons living with HIV/AIDS in the United States.
Despite significant advances in HIV/AIDS treatment and prognosis, older adults living with HIV (OALH) face a number of unique challenges and circumstances that can lead to exacerbated symptoms and poorer outcomes, despite demonstrating generally better ART adherence than their younger counterparts. These detrimental outcomes are due to both chronological aging and cohort effects as well as social and behavioral factors and long-term ART use. For instance, neurocognitive deficits and neuropsychiatric symptoms, including depression, anxiety, apathy, and fatigue, are often observed among OALH, which can result in feelings of loneliness, social isolation, and reduced social support. Taken together, these factors can lead to elevated levels of problems with everyday functioning (e.g., activities of daily living) among OALH. In addition, sociocultural factors such as race/ethnicity, ageism, sexism, homophobia, transphobia, geographic region, socioeconomic status and financial well-being, systemic barriers and disparities, and cultural values and beliefs play an influential role in determining outcomes.
Notwithstanding the challenges associated with living with HIV/AIDS in later life, many persons living with HIV/AIDS are aging successfully. HIV/AIDS survivor and community mobilization efforts, as well as integrated care models, have resulted in some significant improvements in overall HIV/AIDS patient care. In addition, interventions aimed at improving successful aging outcomes among OALH are being developed in an attempt to effectively reduce the psychological and physical morbidity associated with HIV disease.
Life is filled with goals or intentions that people hope to realize. Some of these are rather mundane (e.g., remembering to purchase a key ingredient for a recipe when stopping at the market), while others are more significant (e.g., remembering to pick up one’s child from school at the end of the day). Prospective memory represents the ability to form and then realize intentions at an appropriate time. A fundamental aspect of prospective memory is that one is engaged in one or more tasks (i.e., ongoing activities) between the formation of an intention and the opportunity to realize the goal. For instance, in the shopping example, one might form the intention at home and then travel to the market and collect several other items before walking past the desired ingredient. Considerable research has demonstrated that the efficiency of prospective memory declines with age, although age-related differences are not universal.
The neurocognitive processes underpinning age-related differences in the formation and realization of delayed intentions have been investigated in studies using event-related brain potentials. This research reveals that age-related differences in prospective memory arise from the disruption of neural systems supporting the successful encoding of intentions, the detection of prospective memory cues, and possibly processes supporting the retrieval of intentions from memory when a cue is encountered or efficiently shifting from the ongoing activity to the prospective element of the task. Therefore, strategies designed to ameliorate age-related declines in prospective memory should target a variety of processes engaged during the encoding, retrieval, and enactment of delayed intentions.