Cognition 

Written By Tanja Goltnik

Cognition represents the internal processes involved in making sense of the environment and deciding what feedback would be most appropriate in response to it. Internal processes include attention, learning, reasoning and thinking, problem solving, language, memory and perception.

Patients with FND often report problems with memory, concentration, difficulty finding words and report fog in the head. These symptoms may be secondary and occur alongside primary symptoms such as movement disorders, or they may be primary and result in a diagnosis of a cognitive functional neurological disorder. It is important to have a thorough and comprehensive neuropsychological assessment to determine whether symptoms are functional in origin or suggestive of mild cognitive impairment or even a form of dementia.

Mild cognitive impairment

Mild cognitive impairment is a syndrome of cognitive decline that is greater than that resulting from normal ageing. It represents an intermediate stage between the normal changes of ageing and dementia, and progresses to dementia(most commonly Alzheimer's dementia) in more than half of patients within five years. The diagnosis is made on the basis of the following:

  • Perceived change in cognitive functioning (e.g. memory, concentration, learning, thinking, etc.)

  • The possibility of clinical dementia is excluded

  • Decline in one or more cognitive domains

  • Intactness of independent functioning (e.g. patients have only minor problems such as the inability to remember a shopping list)

  • No other neurological, psychiatric or medical cause of memory impairment

 

There are four subtypes of mild cognitive impairment:

    • Memory impairment

    • Memory impairment combined with impairment in other cognitive areas

    • Impaired second cognitive domain

    • Several other cognitive areas are impaired

 Alzheimer's dementia

Alzheimer's dementia is a disease characterised by progressive cognitive-behavioural decline that impairs an individual's daily functioning and severely impairs their quality of life (Wilson et al., 2012). 

Signs that indicate Alzheimer's dementia include:

  • Memory decline (difficulty in forgetting/recalling information)

  • Temporal and spatial confusion

  • Attention and problem-solving problems (problems with correct decision-making)

  • Language difficulties (speaking and/or writing)

  • Social isolation

  • Changes in mood and personality traits

Pathological evidence is needed to diagnose definite Alzheimer's disease. Progressive decline in memory and other cognitive areas affected must be verified by clinical tests and neuropsychological testing. A family history of a genetic mutation in AD and/or genetic testing and the absence of another disease or disorder that might better explain the decline in memory and other cognitive domains should also be considered. 

Unfortunately, there is no test yet developed to diagnose Alzheimer's disease. Diagnosis therefore involves examining the family and medical diagnosis of the individual, subjective assessment of cognitive and behavioural changes, asking relatives about the patient's cognitive changes, and performing cognitive, blood and neurological tests.
Strategies and protective factors against cognitive decline

 

How to improve cognitive skills?

  • Cognitive reserve refers to the brain's plasticity and the reorganisation of brain networks in a way that compensates for normal age-related cognitive decline, and represents the brain's store of all the mental abilities we have acquired over a lifetime. Individuals who have developed a greater cognitive reserve over their lifetime have a lower risk of developing dementia and a lower impact of cognitive impairment. Cognitive reserve is strengthened:

    • Education

    • Careers requiring moderate to high levels of cognitive activity

    • Leisure activities involving different cognitive domains

    • Bilingualism (can delay the onset of dementia by 4-5 years)

  • Chronic sleep deprivation is one of the main risk factors for cognitive decline. Sleep is a time of detoxification of oxidation products and consolidation of memory - short-term memory is converted into long-term memory, unnecessary memories are eliminated, thought processes are organised and new connections are made.

    For more information on sleep and simple ways to improve the quality of your sleep, click here.

  • Healthy eating habits can be a key protection against severe cognitive decline and the development of Alzheimer's disease and other types of dementia in late adulthood.

    The Framingham Longitudinal Study (2010) concluded that cognitive decline is slower in individuals who have higher levels of omega-3 fats in their blood, eat a variety of fruit and vegetables, avoid sugar and prefer plant-based sources of protein. It has also been shown that individuals with high intakes of vitamins E and C had slower cognitive decline and a lower risk of developing Alzheimer's dementia than those individuals with low intakes of these vitamins. In a meta-analysis of 15 studies examining the effect of alcohol on the risk of developing dementia, low or moderate levels of alcohol consumption were associated with a lower risk of developing Alzheimer's disease and dementia. There is also evidence that higher levels of antioxidant intake reduce the risk of developing Alzheimer's disease because it also lowers the risk of developing cerebro-vascular disease (Reit, et al., 2011).

  • Many studies suggest that physical activity is associated with better brain functioning and a reduced risk of developing diseases that are consequences of pathological ageing (Erickson, et al.,2013; Frederiksen, et al.,2015; Tan, et al.,2010, Weuve, et al.,2004; Hedden and Gabrieli, 2014).

  • Establishing new relationships, taking up new hobbies in the company of other people, and maintaining positive and loving interpersonal relationships throughout life, affects the adaptive fitness of the brain, improves well-being and enables the formation of new neural pathways (Poulain, et al, 2013; Waldinger and Shulz, 2010; Wilson, et al., 2007; Fratiglioni, et al., 2004). There is a large body of rigorous research linking social inclusion to slower cognitive decline (Fratiglioni, et al.,2004), better immune systems(Sternberg, 2001), happiness and well-being( Waldinger and Shulz, 2010). Many studies have concluded that both young and older individuals who engage in cognitively stimulating activities such as learning, reading or playing mind games will have a lower risk of developing dementia than individuals who do not engage in these activities. Cognitive training has also been found to have an impact on improving memory, resonance and mental processing speed in older individuals (Reit, et al., 2011).

  • Cognitive lapses are common in normal populations. It can happen to anyone that they forget where they left their keys, parked their car or if they locked the house when they left home.

 

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Tanja Goltnik
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