Dementias Flashcards
What is dementia?
- non acute cognitive decline that interferes with everyday functioning
- multidimensional disorder: multiple areas affected
- progressive: constantly changing/getting worse
What cognitive problems occur in dementia?
- memory
- language (lose words)
- visuospatial (disoriented in space)
- executive (overwhelmed by novel things)
- affective/personality (change in mood, aggression)
- absence of delirium
What are the cortical dementias?
- alzheimer’s disease
What are the subcortical dementias?
- Parkinson’s disease
- Huntington’s disease
What is explored for a differential diagnosis?
- aging
- MCI
- focal lesions
- delirium
- depression
- visual and auditory deficits
- psychosis
- static encephalopathy
What are the neuropsychological syndromic patterns within dementia?
- anterograde amnesic disorder
- frontotemporal dementia
- semantic dementia (receptive lang.)
- primary progressive aphasia (expressive lang.)
- posterior cerebral cortical atrophy
- dementia with psychomotor slowing
What are the neuronal tau protein abnormalities?
- neurofibrillary tangles (intracellular)
- neuritic (senile) plaques (extracellular)
- granulovacuolar bodies (intracellular)
Where do neuronal tau protein abnormalities occur?
- in associative cortex and hippocampal area
What are the neurotransmitter disturbances?
- acetylcholine
- serotonin
- catecholamines (DA and NE)
What are the details of the tau protein abnormalities?
- all correlate with severity of disease
- all are seen in non-demented elders but less and not outside of the hippocampal regions
What areas are associated with impaired episodic memory?
- bilateral medial temporal
- hippocampus (CA1)
- entorhinal cortex (subiculum)
- amygdala
- parahippocampal gyrus
What areas are associated with impaired semantic and implicit memory?
- association cortex
What areas are associated with impaired organization, encoding, and source memory?
- frontal lobes
What areas are associated with the intact procedural memory?
- relatively intact basal ganglia
What is the most common dementia?
- alzheimer’s disease (50-80%)
What are the risk factors for alzheimer’s?
- family history
- APOE genotype
- very low education level
- brain reserve
- early head injury
- cardiovascular disease
What kind of morphological changes happen with alzheimer’s?
- atrophy
- especially in memory and language areas
What is implicated in memory and learning for alzheimer’s disease?
- semantic memory
- new learning
- vulnerability to interference
- spared recognition during early stages
- tangle formation in cholinergic projection neurons
- possible implicit learning
What is implicated in language for alzheimer’s disease?
- word finding difficulties
- lexical access and semantic processing problems
- language may progressively deteriorate
- writing is compromised early but reading is spared
What is implicated in visuospatial function for alzheimer’s disease?
- agnosia (later)
- impaired performance on Judgment of Line Orientation test
- impaired visuoconstructional ability
What is implicated in executive functions for alzheimer’s disease?
- high sensitivity
- judgement, abstract reasoning, problem solving, and complex decision making processes
- working memory
- divided attention, shifting and other attentional control problems
- multitasking is impaired
What are some general features of an alzheimer’s neuropsychological profile?
- disorientation
- apraxia
- motor and psychomotor dysfunction
- anosognosia
- behavioural and affective changes (apathy, agitation, anxiety, irritability, depression, disinhibition)
What groups are affected by dementia with lewy bodies?
- over 50 year old
- slightly more males
- people with ApoE4 allele subgroup
- more common than previously thought
How are the symptoms of dementia with lewy bodies?
- multiple cognitive deficits, often fluctuating
- extrapyramidal designs (Parkinsonism)
- hallucinations/delusions
What are lewy bodies?
- intracytoplasmic inclusions
- made of synuclein protein
How does dementia with lewy bodies compare to alzheimer’s?
- DLB: more rapid decline
- slightly better memory performance but worse executive functions
What is the overall profile of dementia with lewy bodies?
- lack of initiative and apathy
- visuospatial and visuoconstructional impairments
- psychomotor and motor slowing
- delusional thinking
- outrageous hallucinations
What are the symptoms of frontotemporal dementia?
- executive functions severely affected
- personality changes
- loss of insight, disinhibition
- may have motor problems or apraxia
What is the etiology of frontotemporal dementia?
- generally unknown
- genetic component in many: tau pathology, mutated tau gene (chromosome 17), TBI
What groups are affected by frontotemporal dementia?
- younger age of onset (40-65)
- 20% of all progressive dementias cases
What is the frontaltemporal dementia neurophysiology?
- mirovascular defects (ischemic)
- astrocytic gliosis
- often with “Pick’s bodies”: enlarged, balloon-shaped cells, intracytoplasmic, fill entire cell, tau based
What is anterograde amnesic disorder?
- difficulty in accessing information from the present (ex. who visited yesterday)
What is semantic dementia?
- degradation of areas that process language
