Cognitive impairment

Last updated
Cognitive impairment
Other namesCognitive deficit
Specialty Psychiatry

Cognitive impairment is an inclusive term to describe any characteristic that acts as a barrier to the cognition process or different areas of cognition. [1] Cognition, also known as cognitive function, refers to the mental processes of how a person gains knowledge, uses existing knowledge, and understands things that are happening around them using their thoughts and senses. [2] A cognitive impairment can be in different domains or aspects of a person's cognitive function including memory, attention span, planning, reasoning, decision-making, language (comprehension, writing, speech), executive functioning, and visuospatial functioning. The term cognitive impairment covers many different diseases and conditions and may also be symptom or manifestation of a different underlying condition. Examples include impairments in overall intelligence (as with intellectual disabilities),specific and restricted impairments in cognitive abilities (such as in learning disorders like dyslexia), neuropsychological impairments (such as in attention, working memory or executive function), or it may describe drug-induced impairment in cognition and memory (such as that seen with alcohol, glucocorticoids, [3] and the benzodiazepines. [4] ). Cognitive impairments may be short-term, progressive (gets worse over time) or permanent. [2]

Contents

There are different approaches to assessing or diagnosing a cognitive impairment including neuropsychological testing using various different tests that consider the different domains of cognition. Examples of shorter assessment clinical tools include the Mini Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA). [5] There are many different syndromes and pathologies that cause cognitive impairments including dementia or major neurocognitive disorder and alzheimer's disease. [5]

Cause

Cognitive impairments may be caused by many different factors including environmental factors or injuries to the brain (e.g. traumatic brain injury), neurological illnesses, or mental disorders. [2] While more common in elderly people, not all people who are elderly have cognitive impairments. [2] Some known causes of cognitive impairments that are more common in younger people are: chromosomal abnormalities or genetic syndromes, exposure to teratogens or birth-defect causing agents while in utero (e.g. prenatal exposure to drugs), undernourishment, poisonings, autism, and child abuse. [2] Stroke, dementia, mental health disorders such as depression or schizophrenia, drug, substance, or alcohol abuse, brain tumours, nutritional deficiencies or malnutrition, brain injuries, hormonal disorders, and other chronic disorders may result in cognitive impairment with aging. Cognitive impairment may also be caused by a pathology in the brain. Examples include Alzheimer's disease, Parkinson's disease, dementia caused by HIV, Lewy Body dementia, Huntington disease. [2]

Short term cognitive impairments can be caused by pharmaceutical agents or drugs such as tranquilizers or sedatives. [2]

Screening

Screening for cognitive impairment in those over the age of 65 without symptoms is of unclear benefit versus harm as of 2020. [6] In a large population-based cohort study included 579,710 66-year-old adults who were followed for a total of 3,870,293 person-years (average 6.68 ± 1.33 years per person), subjective cognitive decline was significantly associated with an increased risk of subsequent dementia. [7]

In addition to a series of cognitive tests, general practitioner physicians often also rely on clinical judgement for diagnosing cognitive impairments. [8] Clinical judgement is ideal when paired with additional tests to that permit the medical professional to confirm the diagnosis or confirm the absence of a diagnosis. [8] Clinical judgement in these cases may also help inform the choice in additional tests. [8]

Treatment

Deciding on an appropriate treatment for people with cognitive decline takes clinical judgement based on the diagnosis (the specific cognitive problem), the person's symptoms, other patient factors included expectations and the person's own ideas, and previous approaches to helping the person. [8]

Other findings

Although one would expect cognitive decline to have major effects on job performance, it seems that there is little to no correlation of health with job performance. With the exception of cognitive-dependent jobs such as air-traffic controller, professional athlete, or other elite jobs, age does not seem to impact one's job performance. This obviously conflicts with cognitive tests given, so the matter has been researched further. One possible reason for this conclusion is the rare need for a person to perform at their maximum. There is a difference between typical functioning, that is – the normal level of functioning for daily life, and maximal functioning, that is – what cognitive tests observe as our maximum level of functioning. As the maximum cognitive ability that we are able to achieve decreases, it may not actually affect our daily lives, which only require the normal level. [9]

Some studies have indicated that childhood hunger might have a protective effect on cognitive decline. One possible explanation is that the onset of age-related changes in the body can be delayed by calorie restriction. Another possible explanation is the selective survival effect, as the study participants who had a childhood with hunger tend to be the healthiest of their era. [10]

Prognosis

When a person's level of cognition declines, it is often harder to live in an independent setting and some people have trouble taking care of themselves and the burden on the people caring for them can increase. Some people require supportive healthcare and in some cases institutionalization. [5]

Research

The role of light therapy for treating people with cognitive impairment or dementia is not fully understood. [11] [12] [13] [14]

See also

Related Research Articles

<span class="mw-page-title-main">Aphasia</span> Inability to comprehend or formulate language

In aphasia, a person may be unable to comprehend or unable to formulate language because of damage to specific brain regions. The major causes are stroke and head trauma; prevalence is hard to determine but aphasia due to stroke is estimated to be 0.1–0.4% in the Global North. Aphasia can also be the result of brain tumors, epilepsy, autoimmune neurological diseases, brain infections, or neurodegenerative diseases.

<span class="mw-page-title-main">Dementia</span> Long-term brain disorders causing impaired memory, thinking and behavior

Dementia is a syndrome associated with many neurodegenerative diseases, which is characterized by a general decline in cognitive abilities that impacts a person's ability to perform everyday activities. This typically involves problems with memory, thinking, behavior, and motor control. Aside from memory impairment and a disruption in thought patterns, the most common symptoms include emotional problems, difficulties with language, and decreased motivation. The symptoms may be described as occurring in a continuum over several stages. Dementia ultimately has a significant effect on the individual, caregivers, and on social relationships in general. A diagnosis of dementia requires the observation of a change from a person's usual mental functioning and a greater cognitive decline than what is caused by normal aging.

<span class="mw-page-title-main">Dementia with Lewy bodies</span> Type of progressive dementia

Dementia with Lewy bodies (DLB) is a type of dementia characterized by changes in sleep, behavior, cognition, movement, and regulation of automatic bodily functions. Memory loss is not always an early symptom. The disease worsens over time and is usually diagnosed when cognitive impairment interferes with normal daily functioning. Together with Parkinson's disease dementia, DLB is one of the two Lewy body dementias. It is a common form of dementia, but the prevalence is not known accurately and many diagnoses are missed. The disease was first described on autopsy by Kenji Kosaka in 1976, and he named the condition several years later.

<span class="mw-page-title-main">Vascular dementia</span> Dementia resulting from stroke

Vascular dementia is dementia caused by a series of strokes. Restricted blood flow due to strokes reduces oxygen and glucose delivery to the brain, causing cell injury and neurological deficits in the affected region. Subtypes of vascular dementia include subcortical vascular dementia, multi-infarct dementia, stroke-related dementia, and mixed dementia.

<span class="mw-page-title-main">Neuropsychological test</span> Assess neurological function associated with certain behaviors and brain damage

Neuropsychological tests are specifically designed tasks that are used to measure a psychological function known to be linked to a particular brain structure or pathway. Tests are used for research into brain function and in a clinical setting for the diagnosis of deficits. They usually involve the systematic administration of clearly defined procedures in a formal environment. Neuropsychological tests are typically administered to a single person working with an examiner in a quiet office environment, free from distractions. As such, it can be argued that neuropsychological tests at times offer an estimate of a person's peak level of cognitive performance. Neuropsychological tests are a core component of the process of conducting neuropsychological assessment, along with personal, interpersonal and contextual factors.

<span class="mw-page-title-main">Donepezil</span> Medication used for dementia

Donepezil, sold under the brand name Aricept among others, is a medication used to treat dementia of the Alzheimer's type. It appears to result in a small benefit in mental function and ability to function. Use, however, has not been shown to change the progression of the disease. Treatment should be stopped if no benefit is seen. It is taken by mouth or via a transdermal patch.

Cognitive disorders (CDs), also known as neurocognitive disorders (NCDs), are a category of mental health disorders that primarily affect cognitive abilities including learning, memory, perception, and problem-solving. Neurocognitive disorders include delirium, mild neurocognitive disorders, and major neurocognitive disorder. They are defined by deficits in cognitive ability that are acquired, typically represent decline, and may have an underlying brain pathology. The DSM-5 defines six key domains of cognitive function: executive function, learning and memory, perceptual-motor function, language, complex attention, and social cognition.

The mini–mental state examination (MMSE) or Folstein test is a 30-point questionnaire that is used extensively in clinical and research settings to measure cognitive impairment. It is commonly used in medicine and allied health to screen for dementia. It is also used to estimate the severity and progression of cognitive impairment and to follow the course of cognitive changes in an individual over time; thus making it an effective way to document an individual's response to treatment. The MMSE's purpose has been not, on its own, to provide a diagnosis for any particular nosological entity.

<span class="mw-page-title-main">Primary progressive aphasia</span> Medical condition

Primary progressive aphasia (PPA) is a type of neurological syndrome in which language capabilities slowly and progressively become impaired. As with other types of aphasia, the symptoms that accompany PPA depend on what parts of the left hemisphere are significantly damaged. However, unlike most other aphasias, PPA results from continuous deterioration in brain tissue, which leads to early symptoms being far less detrimental than later symptoms.

Cognitive reserve is the mind's and brain's resistance to damage of the brain. The mind's resilience is evaluated behaviorally, whereas the neuropathological damage is evaluated histologically, although damage may be estimated using blood-based markers and imaging methods. There are two models that can be used when exploring the concept of "reserve": brain reserve and cognitive reserve. These terms, albeit often used interchangeably in the literature, provide a useful way of discussing the models. Using a computer analogy, brain reserve can be seen as hardware and cognitive reserve as software. All these factors are currently believed to contribute to global reserve. Cognitive reserve is commonly used to refer to both brain and cognitive reserves in the literature.

A cognitive intervention is a form of psychological intervention, a technique and therapy practised in counselling. It describes a myriad of approaches to therapy that focus on addressing psychological distress at a cognitive level. It is also associated with cognitive therapy, which focuses on the thought process and the manner by which emotions have bearing on the cognitive processes and structures. The cognitive intervention forces behavioral change. Counselors adopt different technique level to suit the characteristic of the client. For instance, when counseling adolescents, a more advanced strategy is adopted than the intervention used in children. Before the intervention, an initial cognitive assessment is also conducted to cover the concerns of the cognitive approach, which cover the whole range of human expression - thought, feeling, behavior, and environmental triggers.

Brain training is a program of regular activities purported to maintain or improve one's cognitive abilities. The phrase “cognitive ability” usually refers to components of fluid intelligence such as executive function and working memory. Cognitive training reflects a hypothesis that cognitive abilities can be maintained or improved by exercising the brain, analogous to the way physical fitness is improved by exercising the body. Cognitive training activities can take place in numerous modalities such as cardiovascular fitness training, playing online games or completing cognitive tasks in alignment with a training regimen, playing video games that require visuospatial reasoning, and engaging in novel activities such as dance, art, and music.

Alcohol-related dementia (ARD) is a form of dementia caused by long-term, excessive consumption of alcohol, resulting in neurological damage and impaired cognitive function.

Mild cognitive impairment (MCI) is a neurocognitive disorder which involves cognitive impairments beyond those expected based on an individual's age and education but which are not significant enough to interfere with instrumental activities of daily living. MCI may occur as a transitional stage between normal aging and dementia, especially Alzheimer's disease. It includes both memory and non-memory impairments. The cause of the disorder remains unclear, as well as both its prevention and treatment, with some 50 percent of people diagnosed with it going on to develop Alzheimer's disease within five years. The diagnosis can also serve as an early indicator for other types of dementia, although MCI may remain stable or even remit.

The prevention of dementia involves reducing the number of risk factors for the development of dementia, and is a global health priority needing a global response. Initiatives include the establishment of the International Research Network on Dementia Prevention (IRNDP) which aims to link researchers in this field globally, and the establishment of the Global Dementia Observatory a web-based data knowledge and exchange platform, which will collate and disseminate key dementia data from members states. Although there is no cure for dementia, it is well established that modifiable risk factors influence both the likelihood of developing dementia and the age at which it is developed. Dementia can be prevented by reducing the risk factors for vascular disease such as diabetes, high blood pressure, obesity, smoking, physical inactivity and depression. A study concluded that more than a third of dementia cases are theoretically preventable. Among older adults both an unfavorable lifestyle and high genetic risk are independently associated with higher dementia risk. A favorable lifestyle is associated with a lower dementia risk, regardless of genetic risk. In 2020, a study identified 12 modifiable lifestyle factors, and the early treatment of acquired hearing loss was estimated as the most significant of these factors, potentially preventing up to 9% of dementia cases.

Pseudodementia is a condition where mental cognition can be temporarily decreased. The term pseudodementia is applied to the range of functional psychiatric conditions such as depression, schizophrenia and other psychosis, mania, dissociative disorder and conversion disorder that may mimic organic dementia, but are essentially reversible on treatment. Pseudodementia typically involves three cognitive components: memory issues, deficits in executive functioning, and deficits in speech and language. Specific cognitive symptoms might include trouble recalling words or remembering things in general, decreased attentional control and concentration, difficulty completing tasks or making decisions, decreased speed and fluency of speech, and impaired processing speed. People with pseudodementia are typically very distressed about the cognitive impairment they experience. Two treatments found to be effective for the treatment of depression may also be beneficial in the treatment of pseudodementia: Cognitive behavioral therapy (CBT) which identifies behaviors that positively and negatively impact mood, and Interpersonal therapy which focuses on identifying ways in which interpersonal relationships contribute to depression.

Psychological therapies for dementia are starting to gain some momentum. Improved clinical assessment in early stages of Alzheimer's disease and other forms of dementia, increased cognitive stimulation of the elderly, and the prescription of drugs to slow cognitive decline have resulted in increased detection in the early stages. Although the opinions of the medical community are still apprehensive to support cognitive therapies in dementia patients, recent international studies have started to create optimism.

<span class="mw-page-title-main">Alzheimer's disease</span> Progressive neurodegenerative disease

Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens, and is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation, mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the average life expectancy following diagnosis is three to twelve years.

The Addenbrooke's Cognitive Examination (ACE) and its subsequent versions are neuropsychological tests used to identify cognitive impairment in conditions such as dementia.

Geriatric psychology is a subfield of psychology that specializes in the mental and physical health of individuals in the later stages of life. These specialized psychologists study a variety of psychological abilities that deplete as aging occurs such as memory, learning capabilities, and coordination. Geriatric psychologists work with elderly clients to conduct the diagnosis, study, and treatment of certain mental illnesses in a variety of workplace settings. Common areas of practice include loneliness in old age, depression, dementia, Alzheimer's disease, vascular dementia, and Parkinson's disease.

References

  1. ↑ Coren, Stanley; Lawrence M. Ward; James T. Enns (1999). Sensation and Perception. Harcourt Brace. p. 9. ISBN   0-470-00226-3.
  2. 1 2 3 4 5 6 7 Dhakal, Aayush; Bobrin, Bradford D. (2023), "Cognitive Deficits", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID   32644478 , retrieved 2023-04-12
  3. ↑ Belanoff, Joseph K.; Gross, Kristin; Yager, Alison; Schatzberg, Alan F. (2001). "Corticosteroids and cognition". J Psychiatr Res. 35 (3): 127–45. doi:10.1016/s0022-3956(01)00018-8. PMID   11461709.
  4. ↑ Kalachnik, JE.; Hanzel, TE.; Sevenich, R.; Harder, SR. (Sep 2002). "Benzodiazepine behavioral side effects: review and implications for individuals with mental retardation". Am J Ment Retard. 107 (5): 376–410. doi:10.1352/0895-8017(2002)107<0376:BBSERA>2.0.CO;2. ISSN   0895-8017. PMID   12186578.
  5. 1 2 3 Taylor-Rowan, Martin; Kraia, Olga; Kolliopoulou, Christina; Noel-Storr, Anna H.; Alharthi, Ahmed A.; Cross, Amanda J.; Stewart, Carrie; Myint, Phyo K.; McCleery, Jenny; Quinn, Terry J. (2022-08-22). "Anticholinergic burden for prediction of cognitive decline or neuropsychiatric symptoms in older adults with mild cognitive impairment or dementia". The Cochrane Database of Systematic Reviews. 2022 (8): CD015196. doi:10.1002/14651858.CD015196.pub2. ISSN   1469-493X. PMC   9394684 . PMID   35994403.
  6. ↑ US Preventive Services Task, Force.; Owens, DK; Davidson, KW; Krist, AH; Barry, MJ; Cabana, M; Caughey, AB; Doubeni, CA; Epling JW, Jr; Kubik, M; Landefeld, CS; Mangione, CM; Pbert, L; Silverstein, M; Simon, MA; Tseng, CW; Wong, JB (25 February 2020). "Screening for Cognitive Impairment in Older Adults: US Preventive Services Task Force Recommendation Statement". JAMA. 323 (8): 757–763. doi: 10.1001/jama.2020.0435 . PMID   32096858.
  7. ↑ Lee, YC; Kang, JM; Lee, H; Kim, K; Kim, S; Yu, TY; Lee, EM; Kim, CT; Kim, DK; Lewis, M; Won, HH; Jessen, F; Myung, W (6 May 2020). "Subjective cognitive decline and subsequent dementia: a nationwide cohort study of 579,710 people aged 66 years in South Korea". Alzheimer's Research & Therapy. 12 (1): 52. doi: 10.1186/s13195-020-00618-1 . PMC   7203882 . PMID   32375880. S2CID   218513668.
  8. 1 2 3 4 Creavin, Samuel T; Noel-Storr, Anna H; Langdon, Ryan J; Richard, Edo; Creavin, Alexandra L; Cullum, Sarah; Purdy, Sarah; Ben-Shlomo, Yoav (2022-06-16). Cochrane Dementia and Cognitive Improvement Group (ed.). "Clinical judgement by primary care physicians for the diagnosis of all-cause dementia or cognitive impairment in symptomatic people". Cochrane Database of Systematic Reviews. 2022 (6): CD012558. doi:10.1002/14651858.CD012558.pub2. PMC   9202995 . PMID   35709018.
  9. ↑ Salthouse, Timothy (10 January 2012). "Consequences of Age-Related Cognitive Declines". Annual Review of Psychology . 63 (1): 201–226. doi:10.1146/annurev-psych-120710-100328. PMC   3632788 . PMID   21740223.
  10. ↑ Barnes, L. L.; Wilson, R. S.; Everson-Rose, S. A.; Hayward, M. D.; Evans, D. A.; Mendes de Leon, C. F. (26 October 2015). "Effects of early-life adversity on cognitive decline in older African Americans and whites". Neurology. 79 (24): 2321–7. doi:10.1212/WNL.0b013e318278b607. PMC   3578376 . PMID   23233682.
  11. ↑ Chiu, HL; Chan, PT; Chu, H; Hsiao, SS; Liu, D; Lin, CH; Chou, KR (October 2017). "Effectiveness of Light Therapy in Cognitively Impaired Persons: A Metaanalysis of Randomized Controlled Trials". Journal of the American Geriatrics Society. 65 (10): 2227–2234. doi:10.1111/jgs.14990. PMID   28734045. S2CID   802232.
  12. ↑ Forbes, Dorothy; Blake, Catherine M; Thiessen, Emily J; Peacock, Shelley; Hawranik, Pamela (2014-02-26). Cochrane Dementia and Cognitive Improvement Group (ed.). "Light therapy for improving cognition, activities of daily living, sleep, challenging behaviour, and psychiatric disturbances in dementia". Cochrane Database of Systematic Reviews. 2014 (2): CD003946. doi:10.1002/14651858.CD003946.pub4. PMC   10837684 . PMID   24574061.
  13. ↑ Lu, Xinlian; Liu, Chengyu; Shao, Feng (2023-04-05). "Phototherapy improves cognitive function in dementia: A systematic review and meta-analysis". Brain and Behavior. 13 (5): e2952. doi:10.1002/brb3.2952. ISSN   2162-3279. PMC   10176000 . PMID   37017012.
  14. ↑ Fong, Kenneth Nk; Ge, Xiangyang; Ting, K. H.; Wei, Minchen; Cheung, Hilda (2023). "The Effects of Light Therapy on Sleep, Agitation and Depression in People With Dementia: A Systematic Review and Meta-analysis of Randomized Controlled Trials". American Journal of Alzheimer's Disease and Other Dementias. 38: 15333175231160682. doi: 10.1177/15333175231160682 . ISSN   1938-2731. PMC   10578524 . PMID   36924042.

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.