4. Cognitive disorders Flashcards
research in late adulthood cognitive disorders
Late adulthood is the fastest growing but least researched segment of the population
More stereotypes about late adulthood than any other age group
The ageing population in Australia
In 2004, Australians over the age of 65 made up 13% of the population, by 2051 this is projected to rise to 27%.
Dementia
symptoms of any illness that causes a progressive decline in a person’s cognitive function
Prevalence and age of dementia
Most people with dementia are over the age of 65 but only a small proportion of older people over 65 have dementia. However, the chance of developing dementia increases exponentially as we get even older (i.e., the oldest old)
Stages of AD: Behavioural level
- AD brain changes starts decades before symptoms show
- Amnestic MCI: memory problems, other cognitive functions OK; brain compensates for changes
- Cognitive decline accelerates afte AD diagnosed
- Total loss of independent function
Stages of AD: Bioligical level
- Both genes and non-genetic factors contribute to each individual’s risk
- A waste protein, beta-amyloid, probably begins to be deposited in the brain tissue in early adulthood
- Early damage to some brain cells ay be present
- Accumulating beta-amyloid forms plaques (insoluble deposits) that provoke inflammation, contributing to further brain cell injury
- The disease, which has been slowly damaging the brain for decades, may be diagnosed
- the patient loses the ability to function independently
Old definition of AD
Symptom-based: Progressive decline in a person’s cognitive function
causes of dementia
The most common cause of dementia is Alzheimer’s disease (AD), and accounts for approximately half of all cases of dementia. Vascular dementia (VaD) related to strokes is the next most common cause. Other forms include Frontotemporal dementia, and Dementia with Lewy bodies. Each form of dementia has its own pattern of symptoms, and correct diagnosis is important as treatment and management vary.
Key features of AD
1- Memory Impairment (impaired ability to learn new info or recall previously known info) 2- One or more of the following: -Aphasia -Apraxia -Agnosia -Executive dysfuntion
Neuopathology of AD
Alzheimer’s disease has one important characteristic feature in the brain: Neuritic plaques
neuritic plaques
masses of dying neural material with a toxic protein that damages neurons, beta-amyloid, at their core
Memory profile of AD
- Relatively spared STM and procedural memory (especially motor learning)
- Episodic and semantic memory deficits and impaired verbal and visual learning
- Lots of repetition and intrusion errors on list learning
- Not aided by cueing
- Loss of semantic network (no ‘semantic clustering’ during encoding)
language profile of AD
- Anomic aphasia (impaired confrontation naming)
- General conversation skills relatively preserved until mid-late stages
visuospatial profile of Ad
- Range of visuospatial and spatial orientation deficits
- Clock drawing
Executive function profile of AD
Increased disorganisation
Perseveration
Impaired metacognitive awareness (poor self-monitoring)
Impaired time estimation
Sensory functioning profile of AD
Preserved visual, auditory and tactile acuity
Emotional function profile of AD
Depression highly comorbid
Behavioural and psychiatric disturbance
Behavioural and psychiatric disturbances that occur as a result of AD
Insomnia Persecutory ideation/delusion Hallucinations Apathy Agitation Irritability
AD patients memorising abilities
For AD patients, initial false representation/memory lingers and is hard to revise
AD patients fail to take the richer context into consideration to support their sentence understanding/memory
AD patient’s grammatical knowledge
Some part (subject-verb agreement) of grammatical knowledge remains intact among AD
However, AD patients fail to keep track the number of entities (singular/plural) in the discourse probably due to their memory loss
Delirium
Delirium is an acute confusional state or episode characterised by a sudden onset of impaired cognition.
It is a serious medical problem that is often not recognised by health professionals.
Approximately 10-15% of people admitted to hospital have delirium, and a further 5-40% are thought to develop delirium once in hospital.
Symptoms of delirium
decreased attention span, disorganised thought, rambling speech, and hallucinations and delusions may also develop.
confusion in delirium
Confusion may fluctuate throughout the day, often with a disturbed sleep-wake cycle.
onset of delirium
It has a rapid onset and family and carers may notice a sudden change in level of confusion and general wellbeing.
level of consciousness in delirium
Level of consciousness may also vary, and the person may be hyperalert, with agitation and high levels of arousal, or conversely hypoalert, lethargic and non-responsive.
common causes of delirium
Drug intoxication or withdrawal Sudden onset brain disease (e.g. Meningitis) Infections Electrolyte imbalance Anticholinergic drugs Heart, kidney, liver failure
comorbidity of delirium and dementia
Delirium is different to dementia, although people with dementia are prone to episodes of delirium and both conditions may co-exist.
What must carers and families be aware of in relation to delirium?
It is important for families and carers to note a sudden change in cognition and function as this may be due to delirium.
dementia compared to delirium
Dementia is a progressive condition that has an onset of months to years. The symptom severity of a person with dementia does not appear to change throughout the day.
Dementia and AD compared to normal memory loss
People over 65 are so anxious about having memory loss and developing Dementia, and the best way to distinguish Dementia and AD from normal cognitive declines is to ask yourself: it is probably OK to forget where you park your car or where your car key is this morning but you may want to get serious about it when you can’t remember you come in this morning in a car
why study AD and dementia now?
Family and Societal Toll
In face of financial cutdown for research worldwide, this is an area politicians and governments jump upon
Technology vs. humanity
Advancements in imaging technologies and VR/AR/MR
“Add life to years NOT years to life”
Stay hopeful!
Denise Park’s quote: “I feel reasonably confident that the children of Boomer’s might not have this terrible scourge.”
http://www.frtv.org/2012/07/brain-health-aging-and-alzheimers/
