Flashcards in 7: Aquired brain injury and neurodegenerative diseases Deck (46)
In animal studies, what was the result of leisons on the hippocampus?
Mild memory problems
In animal studies, what was the result of leisons on the hippocampus and amygdala?
Mild memory problems
In animal studies, what was the result of leisons on the hippocampus and rhinal cortex?
Severe memory problems
What is the main function of the rhinal cortex?
Combining sensory input from cortical association areas and inputting them into the hippocampus
How is the hippocampus linked to spatial memory?
Neurons can be specific to places in space. When participants were asked to recall an area, the corresponding neurons were activated which shows the hippocampus provides spatial context
What is Korsakoff's syndrome?
Caused by a thymine deficiency due to alcohol. Results in cortical atrophy and damage to the diensephalon so the hippocampus can't communicate with other areas of the brain
Severe reterograde and anterograde amnesia
How is the consolidation of memories linked to the hippocampus?
Memories first rely completely on the hippocampus and are eventually consolidated into the wider cortex each time the memory is recalled
What causes strokes generally?
A disruption of blood supply to the brain
What is an ischemic stroke?
Oxygen supply to the brain is affected.
Can be either embolic or thrombotic
To do with clots
What is a thrombotic stroke?
Caused by a clot in the brain's blood vessels
What is an embolic stroke?
Caused by a clot somewhere in the body disrupting oxygen to the brain
What is a hemorrhagic stroke?
The rupture of blood vessels in the brain
In what timeframe can motor skills be recovered after a stroke?
In what timeframe can cognitive skills be recovered after a stroke?
What are the language defects resulting from a stroke?
What is aphasia?
Problems producing speech
How is aphasia caused?
Damage to the left hemisphere in the frontal and temporal areas
What is agraphia?
Problems with spelling and writing
How is agraphia caused?
Damage to the left hemisphere visual areas involved in writing
What is alexia?
Problems with reading
How is alexia caused?
Damage to the visual and temporal areas of the left hemisphere
What is the dual route theory of reading? (Alexia)
Dorsal route decodes words and maps them onto sounds
Ventral route directly mapps words to their meaning
What is dementia?
The loss of cognitive functioning that affects daily life and activities
How does Alzheimer's progress?
Over around 10 years it progresses from mild to severe
First issues in memory but later mood disturbances and a loss of independence
What is the prevelence for Alzheimer's?
0.5% at 55 years old and the risk doubles every 5 years
At 80 years old, prevelence is at 15-20%
What parts of the working memory model are affected by Alzheimer's?
Visuospatial sketchpad and central executive
What is the main Alzheimer's treatment?
cholinesterase inhibitors which increase acetylcholine in the brain as it has a role in learning and memory
What is the cholinergic hypothesis of Alzheimer's?
There are reduced levels of acetylcholine in the brain of patients and it can be seen in the early stages of Alzheimer's as well.
How effective are cholinesterase inhibitors as treatment for Alzheimer's?
Effective in half of patients for 2 years before becoming ineffective
When they're taken off the drug, they deline to where they would have been if the drug had never been given - it doesn't slow the disease