Memory & Dementia Flashcards
What is the clinical definition of memory encoding?
process of transforming sensory information for entry into and retention by the memory system
What is the clinical definition of memory storage?
Process of retaining information for later use
What is the clinical definition of memory retrieval?
Process of consciously recovering information
What are the stages of memory?
1) Sensory memory
- large capacity, attention-dependent, very short term
2) Working memory
- limited capacity, short term
3) Long term memory
- infinite capacity and duration
- encode, store, retrieve
What are 2 types of memory loss?
1) Retrograde amnesia
- cannot remember things that happened before a certain event which caused the amnesia
2) Anterograde amnesia
- cannot remember things that happen after a certain event
Why does aging cause a decline in memory without affecting daily function?
↑Age → ↓ability to store new memories
Sensory and long-term memory maintained → only mild decline
What is dementia?
progressive clinical syndrome which involves global deterioration in cognitive function
- exists in a clear state of consciousness
- severe enough to interfere with social and occupational functions
What are 5 symptoms of dementia?
1) Difficulty learning and retaining new information e.g. cannot remember recent conversations
2) Language problems e.g. cannot find the words to express what they want to say
3) Difficulty handling complex tasks
4) Altered behaviour e.g. more passive, less responsive, more irritable or more suspicious
5) Loss of reasoning ability
6) Loss of spatial ability and orientation e.g. finding directions
Which part of the brain encodes for long-term memory?
Medial temporal lobe
What are 3 types of diagnostic imaging used in dementia?
CT, MRI, PET Scans:
Types:
1) Structural
- hippocampus → CSF (black) should not be obvious
2) Functional
- uptake of substances (eg. glucose) → brain f(x)
3) Molecular
- probes into brain tag (eg. ß-amyloid)
What is the use of PET scans in diagnosing dementia?
Detects amyloid deposition/tau protein in brain
- characteristic of dementia
What is classic presentation of alzheimer’s on imaging?
Atrophy of hippocampus
What is classic presentation of Fronto-temporal dementia on imaging?
Atrophy of frontal and temporal lobes
What is classic presentation of large-vessel infarct dementia on imaging?
Cerebral artery occlusion, brain infarct
What are 2 ways to prevent/treat dementia?
1) Lifestyle interventions (FINGER)
- Healthy diet: rich in fruit, vegetables, whole-grains and fish but low in fat & sugar
- exercise: muscle strength training & aerobic exercise
- Education (cognitive training)
- Managing vascular risk factors e.g. managing hypertension
2) Pharmacological
- Lecanemab, etc. (remove amyloid proteins)
