Role of Medial Temporal Lobe (Hippocampus) Flashcards
Define: medial temporal lobe
The inner surface area at the base of and towards the middle of the temporal lobe, containing the hippocampus, amygdaloid and other cortical tissue.
Define: hippocampus
3.5cm curved structure located in each medial temporal lobe which FORMS, CONSOLIDATES and TRANSFERS new declarative explicit memories for storage and aids in SPATIAL MEMORY
How does the hippocampus form now declarative explicit memories?
Temporarily holds and processes different components of new memory - during processing, different compotes are integrated to from the new memory
Where are explicit memories transferred to from the hippocampus for storage?
Probably the same cortical area in which that memory (or parts of that memory) were processed
Define: spatial memory
Memory for the physical location of objects in space (impaired for people with hippocampal damage)
Is the hippocampus involved in stm or implicit procedural memories?
No
Describe the HM (Henry Molaison 1957) case study without results
27 year old had seizures which were thought to originate in either medial temporal lobe; most of medial temporal lobe was removed which caused memory problems
What happened to HM’s memory before surgery?
Partial retrograde amnesia occurred - total loss for 2 years before, and partial for the preceding 10. Parts of explicit memory remained as the hippocampus does not store explicit memory
What happened to HM’s memory after surgery?
Permanent anterograde amnesia - could not form of consolidate and therefore store new declarative memories. Unaffected implicit memory (though could not remember) or STM
Define: lobectomy
Removal of medial temporal lobe
Are symptoms of bilateral lobectomy more severe than unilateral? What are symptoms of unilateral lobectomy on left/right?
Yes; loss of verbal/non verbal memory
