Memory and Dementia Flashcards
What can cause a short term memory loss?
Alcohol, head trauma etc
Two different types of amnesia?
Retrograde or anterograde
Retrograde amnesia?
Lose ability to recall memories that have already been learned
Anterograde amnesia?
Cant create new memories
What are demetias?
A family of symptoms characterized by a decline in cognitive functions sufficient to cause impairment in social and occupational performance
What is the first presenting feature of demetia?
Decline in memory
Most common form of dementia?
Alzheimers
What are initiation deficits/apathy?
Lacking the will to do something
What are visuo-spatial deficits?
Forgetting visual things/locations e.g. forgetting the way home/where they are etc
Most common alzheimer’s symptoms?
Memory, initiation, visuo-spatial and language deficits
Paraphasia?
Struggling to identify the right words
What drives executive function?
Frontal cortex
What is executive funciton?
Risk assessment–> motivated to do x thing but there may be a risk, weighing up pros and cons
Symptoms of having executive function issues?
V risk averse/v risky
What is psychosis?
A psychotic epidose–> is a symptom not a disease itself
Does psychosis occur in AZ?
Yes
How is psychosis treated in AZ?
Antipsychotics that are used to control schizophrenia
Incidence of AZ with age?
Strongly correlated with age
Cause of AZ?
Neurons in the brain dying
Where is the first locus of AZ damage?
Temporal lobes
What is found in the temporal lobes?
Hippocampus and entorhinal corex
Why are memory deficits seen as the first symptoms of AZ?
FIrst affected parts are hippocampus and entorhinal cortex which are involved in memory
What happens to the rest of the brian as AZ spreads?
AZ spreads around the brain
Which parts of the brain are not affected by AZ?
Midbrain/brainstem
Cause of AZ?
Extracellular plaques that form as a result of abnormal beta amyloid, and intracellular tangles made up of abnormal Tau protein
Where is APP found?
Membrane spanning
First action on APP?
Cleaved by alpha secretase
What forms as a result of alpha secretase cleaving APP?
APP alpha (soluble)
What effects does APP alpha have?
Trophic–> positive (“nourishes the neurons”)
What happens to the rest of APP that isn’t cleaved into APP alpha?
Cleaved by gamma secretase into two smaller peptides that can be metabolised
What happens to APP in AZ?
It gets cleaved by beta secretase
Difference between alpha and beta secretase?
Cleavage position on APP
What forms as a result of beta secretase cleavage of APP?
APP beta, and a larger peptide remnant
What cleaves the larger protein remnant formed by beta secretase cleavage?
Gamma secratase
What forms as a result of gamma secretase cleaving the larger peptide remnant from beta secretase?
Beta amyloid 40 or beta amyloid 42
How is ApoE4 involved in AZ?
It can help beta amyloid 40/42 form plaques
General role of ApoE4?
Helps cholesterol and fat soluble vitamins enter neurons
What can beta amyloid plaques do?
Drive production of phosphorylated Tau
What % of AZ cases are sporadic?
90%
What may cause the formation of amyloid beta 40/42?
Enhancement of beta secretase as a result of environmental/disease/inflammation
