memory disorders Flashcards
1
Q
brain structures
A
- different types of memory involve different structures
- damage to hippocampus, poor episodic
- damage to para hippocampal cortex, poor semantic memory
- damage to both regions, poor episodic and semantic
2
Q
causes of amnesia
A
- damage to different structures of the brain cause different syndromes
- causes:surgery, chronic alcohol abuse, brain tumour, dementia, bilateral stroke, closed head injury.
3
Q
retrograde amnesia
A
- poor recall for memories formed before onset of amnesia
- greater for episodic than semantic
- temporal gradient, older memories less impaired
4
Q
consolidation theory
A
- physiological process in the hippocampus leads to formation of long lasting memories
- consolidated memories stored elsewhere, protecting them from effects of hippocampal damage
5
Q
semanticization
A
episodic memories become more like semantic memories over time= protected from the effects of damage
6
Q
reduced learning opportunity
A
- episodic on a single learning experience= explains amnesia
- semantic memories depend of several learning experiences
7
Q
anterograde amnesia
A
- loss of ability to form new memories after onset of amnesia
- results from damage to areas of the brain that are involved in forming new memories
- damage to hippocampus the main cause in most instances
- mammillary bodies and fornix also commonly involved
8
Q
global amnesia
A
- moderate retrograde and severe antergrade
- results from lesions in medial temporal lobe, hippocampus
9
Q
patient hm
A
- amnesic
- suffered from severe epilepsy from age 10
- at age 27 had surgery to remove entire medial temporal lobe
10
Q
korsakoffs syndrome
A
- also known as diencephalic amnesia
- vitmain b1 deficiency from chronic alcoholism
- damage to mammillary bodies in hypothalamus
- poor ability to remember events before or after onset amnesia
- some new learning ability, motor skills
- slight impairment of stm, digit span
11
Q
symptomology
A
- typically has a gradual onset
-Brain damage widespread (hippocampus and frontal) - a precise pattern of damage varies across
-brain plasticity and learning of compensatory strategies
12
Q
issues
A
- events happened before or after amnesia onset?
-damage to frontal lobe = other cognitive deficits
difficult to generalise across patients
does not provide a direct assessment of the impact of brain damage on ltm
13
Q
semantic dementia
A
- severe problems with semantic memory but intact episodic
- severe loss of info about meanings of words and concepts
- difficulty naming pictures/pbjects, single comprehension, categorising and knowing uses and features of objects
- episodic memory and most executive functions reasonably intact in the early stages.
- patient differ in symptoms
- always involves degeneration of anterior temporal lobe
14
Q
double dissociation
A
- amnesia and semantic dementia point to a double dissociation in ltm
- identify that brain damage to one structure disrupts one cognitive process (x) but not another (y)
- also identify brain damage to different structure disrupts cognitive process y but not x
15
Q
amnesia=hippocampus
A
- poor episodic (x)
- intact semantic (y)
