what is organic amnesia
forgetting which is a nueurological cause
how old was patient hm a amnesia patient and what happened to him
19-yr old man suffering from severe epilepsy
The locus of the abnormal electrical activity was in the temporal lobes
what was Scovilles approach for the case of ppt hm
to cut portions of the right and left medial temporal lobes to stop the seizures
what was done to HM after his death
autopsy
Why can we only make inferences from brain autopsies in psychology?
Because the person’s behavior and mental processes can no longer be directly observed. Researchers must rely on postmortem evidence and past behavioral data to infer how brain structures relate to psychological functions.
: Which brain areas were found to affect memory in Patient H.M., and how?
Autopsy showed damage to the hippocampus in particular, but other researchers have also identifed, parahippocampal gyrus and rhinal cortex. This allowed researchers to infer a causal link between these regions and the ability to form new long-term (declarative) memories.
what problems did patient hm develop
verbal and non-verbal memory other cognitive functions were fine.
retaining info for more than a minute
what was found about hm past memories
memories 3 years prior were intact as well as short term memories ( digit span) and could obtain new skills
what are the implications for surgery after this
Neurosurgeons no longer perform bilateral medial lobe surgery
But unilateral surgery can produce severe amnesia if contralateral MTL is diseased
How did research on H.M. and later studies challenge previous ideas about memory localization?
Lashley’s work had suggested memories were widely distributed across the cortex.
H.M.’s case showed that specific MTL lesions cause specific memory deficits → supporting localization.
Milner’s later work on unilateral MTL lobectomies found content-specific deficits:
Left MTL → Verbal memories
Right MTL → Non-verbal (pictorial/spatial) memories
work rejects lashly and supports domain specific functions, especially mtl not across brain areas.
what areas are affected in organic amnesia
The medial temporal lobes
Thalamus (Anterior and dorsomedial nuclei)
Fornix & Mammillary bodies
Basal forebrain
Interconnected structures
What is anterograde amnesia
Impaired memory for events and facts experienced after the onset of amnesia
Patients can vary from mild to severe
What is retrograde amnesia
Impaired memory for event and facts learned before the onset of amnesia
Can cover an extensive or very short period of time
What did Tulving’s patient K.C. reveal about memory systems?
K.C. could not recollect any personally experienced events (episodic memory).
His semantic knowledge (facts and concepts) remained reasonably intact.
Shows that episodic and semantic memory can be independently impaired.
Which type of memory is more affected in patients like H.M. and K.C.?
Episodic memory (personal experiences) shows larger deficits than semantic memory (general knowledge).
Suggests that these two types of memory rely on different neural systems
: What is the typical pattern of retrograde amnesia for episodic memories?
A:
Patients often lose episodic memories from several years before brain damage.
This loss shows a temporal gradient, with recent memories more affected than older ones.
What does the temporal gradient in retrograde amnesia suggest?
Older (remote) memories are more likely to remain intact.
Indicates that over time, memories become consolidated and less dependent on the medial temporal lobe, relying more on neocortical storage.
What are declarative memories
involved in conscious recollection of events and facts. ( explicit memory). Declarative memory involves episodic memory and semantic memory
whar brain structures do declarative memories rely on and what happens if damaged
Declarative (explicit) memory relies on brain structures such as the medial temporal lobe, diencephalon, and basal forebrain, so damage to these areas, as seen in amnesia, impairs conscious recall of facts and events.”
what are non-declarative memories
does not involve conscious recollection , meaning we observe it through behaviour as it is not implicit. Types of these memories include priming and procedural memory. involves structures that are not damaged in amnesia
what does implicit mean in this context
cannot be accessed or manipulated
what are episodic memories
/Storage and retrieval of specific events/Linked to a specific place and time
/Associated with conscious recollection
/three ‘W’—what where when. (Narine 2015b)
what are semantic memories
General knowledge of :Objects. Word meanings,Facts ,People
Lacks a particular connection to time
or place
what is autonetic conciousness
the awareness that characterises the conscious recollection of personal episodes
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Vision46
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Untitled Deck75
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Vision core lecture week 2 part 239
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Consciousness47
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Object recognition and perception77
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Short term memory and working memory31
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Working model of memory42
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Learning and forgetting33
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long term memory system42
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evolution and memory as an adaptation47
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Clinical neuropsychology of memory impairment61
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language22
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decision making - prospect theory, expected utility theory11
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brain assymetry - week 842
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Week 10- problem solving research focus lecture20
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every day memory lecture53
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emotional imagery week 1132
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hormones and decision making30
