Cognitive impairment
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]
Cognitive impairment | |
---|---|
Other names | Cognitive deficit |
Specialty | Psychiatry |
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]
References
- Coren, Stanley; Lawrence M. Ward; James T. Enns (1999). Sensation and Perception. Harcourt Brace. p. 9. ISBN 0-470-00226-3.
- Dhakal, Aayush; Bobrin, Bradford D. (2023), "Cognitive Deficits", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 32644478, retrieved 2023-04-12
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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 (2): CD003946. doi:10.1002/14651858.CD003946.pub4. PMID 24574061.
- 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.
- 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. PMID 36924042.
Further reading
- Das, J.P.; Naglieri, J.A.; Kirby, J.R. (1994). Assessment of Cognitive Processes. Needham Heights, MA: Allyn & Bacon. ISBN 0-205-14164-1.
- Das, J.P. (2002). A better look at intelligence. Current Directions in Psychology, 11, 28–32.
- Goldstein, Gerald; Beers, Susan, eds (2004). Comprehensive Handbook of Psychological Assessment: Volume I: Intellectual and Neurological Assessment. Hoboken, NJ: John Wiley & Sons.
- Kaufman, Alan S. (2000). "Chapter 20: Tests of Intelligence". In Sternberg, Robert J. (ed.). Handbook of Intelligence. Cambridge: Cambridge University Press. pp. 445–476. ISBN 978-0-521-59648-0.
- Naglieri, Jack A.; Otero, Tulio M. (2012). "Chapter 15: The Cognitive Assessment System: From Theory to Practice". In Flanagan, Dawn P.; Harrison, Patti L. (eds.). Contemporary Intellectual Assessment: Theories, tests, and issues (Third ed.). New York: Guilford Press. pp. 376–399. ISBN 978-1-60918-995-2. ERIC ED530599.
- Sattler, Jerome M. (2008). Assessment of Children: Cognitive Foundations. La Mesa (CA): Jerome M. Sattler, Publisher.
- Urbina, Susana (2004). Essentials of Psychological Testing. John Wiley & Sons. ISBN 978-0-471-41978-5.
- Urbina, Susana (2011). "Chapter 2: Tests of Intelligence". In Sternberg, Robert J.; Kaufman, Scott Barry (eds.). The Cambridge Handbook of Intelligence. Cambridge: Cambridge University Press. pp. 20–38. ISBN 978-0-521-73911-5.