Memory Flashcards
(30 cards)
neuroplastic processes
memory and learning
what brain region is affected when you suffer from amnesia?
medial temporal lobe
- episodic memory
Patient H.M.
medial portions of his temporal lobe removed (hippocampus and amygdala)
anterograde amnesia - severely effected
retrograde amnesia - moderately effected
digit span = normal (6 items)
assessment of H.M.
5 tests: 2 LTM deficit, 3 show subconscious memory
digit span + 1 = verbal LTM - could only repeat 8 digits (normal = 15)
block tapping memory span test (other sensory modalities) - couldn’t learn 6 blocks
mirror drawing task (sensorimotor task) = improved with more goes
incomplete picture test (non sensorimotor) = ordered images in sketchiness (improved)
pavlovian conditioning = eye blinking to jet of air combined with a tone. tone elicited blink
global amnesia
affects all modalities
remote memories
distant past
explicit memory
semantic - general facts or information
episodic - autobiographical information (ones own life events)
Patient K.C.
medial temporal lobe damage
severe amnesia but cognitive abilities fine (chess, language, organ)
fine semantic memory
poor episodic
global cerebral ischemia
interception of blood supply to the brain = medial temporal load damage
Patient R.B
global cerebral ischemia
pyramidal layer of hippocampus (CA1 subfield)
transient global amnesia
sudden onset without any evidence or damage
found to be abnormalities in CA1 subfield
cleared 10 days after the attack
korsakoff syndrome (Patient N.A.)
disorder of memory for those who have consumed a lot of alcohol
deficiency in thiamine
damage to neocortex, cerebellum and hippocampus
lesions to medial diencephalon
anterograde amnesia for explicit episodic memories for 2 years up the event - reduced to 2 weeks
would occasionally remember specific irrelevant new memories
monkey model of object recognition
delayed non-matching to sample test
with medial temporal lobectomies struggle with this
model of H.M.
hippocampal damage
delayed non-matching task in rats
mumby box
hippocampus, amygdala, medial temporal cortex = severe memory retention deficits
only moderate deficits when the hippocampus is removed
amygdala has no affect on its own
rodent spatial memory
when hippocampus is removed, spatial abilities are sseverely affected
morris water maze
radial arm maze
place cells
respond when a person is in a specific location
response depends on grid cells
entorhinal cortex
area of medial temporal cortex which contains grid cells
grid cells
evenly spaced place field cells
distance between the cells is flexible
head direction cells
location of head
border cells
borders of environment
Hebb
long term potentiation - cells that fire together wire together
where is LTP conducted
pyramidal and granule cells of the hippocampus
key properties of LTP
lasts for a long time
develops only if presynaptic firing is followed by post
Hebb’s postulate learning
cooccurance
