Lecture 20: Memory Flashcards
what are the two qualitative categories (types) of memory
explicit/declaritive
implicit/nondeclaritive
what is explicit/declaritive memory
easily verbalized because its in consioucness
can often be learned in single exposure
daily episodes, words and their meanings, history
what is the immediate memory
fraction of a second - seconds
what is working memory
seconds-minutes
what is long-term memory
days-years
why could HM make new non declarative memories but could not recall events in his daily life
he had a bilateral medial temporal lobe resection, which is responsible for consolidation moves things from immediate memory to working memory to long term memory)
he could make less errors tracing a drawing because his body remembered how to do it, but he didn’t have memory of practicing the drawing
what are the TWO important structures for declarative memory consolidation
midline diencephalic structures (thalamus/hypothalamus)
medial temporal lobe structures (hippocampus)
what is the lateralization of consolidation
Left diencephalic lesions: verbal memory deficits
Right diencephalic lesions – visual-spatial memory deficits
how does the lateralization of consolidation connect with what we already know about lateralization in the brain
the left side of the brain is important for language, so it makes sense that Left diencephalic lesions cause verbal memory deficits
the right side of the brain is important for spatial attention, so it makes sense that right diencephalic lesions cause visual-spatial memory deficits
what is the primary role of the hippocampus (Medial temporal lobe structures)
Establishes new declarative memories (inability = anterograde amnesia)
what does bigger hippocampal volume mean
better memory
what are the 3 ways A TBI affects declarative memory
Retrograde amnesia: loss of events preceding injury
Post traumatic/anterograde amnesia
(can’t make new memories, making them agitated and disorientated)
historial memory is generally preserved
how does post-traumatic amnesia affect prognosis
best predictors of functional recovery
short duration = better recovery
impacts ‘carryover’ and ability to compensate for memory deficits
what is the GOAT
Clinically useful tool for monitoring post traumatic amnesia
PTA is considered to have ended if a score ≥75 is achieved on three consecutive administrations.
declarative memory storage sties area related to what
the modality in question (e.g. visual cortical areas are involved in storing visual memories).
Degradation in long-term memory proportional to what
the amount of cortex damaged (mass action principle)
what is normal human capacity for meaningless information
7-9 digits (trying to remember things to do grocery lists, etc)
Which 2 factors help with forming memories?
association
motivation and interest
why is association important for storage
Capacity of working memory depends upon meaning to the person and amount of associated information that has already been stored
like remembering new Pokemon when you already know a lot of them
why do motivation and interest influence memory
the adult learning principles
How do we retrieve long-term memories?
appears to involve frontal lobes.
Damage to frontal lobes = difficulty with recall, sometimes accompanied by confabulation
what is implicit/nonclaritive memory
generally not available to consciousness or to verbalize
usually requires many repetitions (gradual learning)
motor skills, associations, priming cues, problem solving skills
which 4 structures does non-declarative memory depend on
premotor cortex
basal ganglia
amygdala
cerebellum
what are the 4 types of Nondeclarative Memory
- Procedural Motor Learning
- Classical Conditioning
- Priming
- Operant Conditioning
what is Procedural Motor Learning
most commonly seen in OT
HM star diagram
playing sports
riding a bike
transfers
playing an instrument, etc
what is classical conditioning
Learn to associate two sensory stimuli
food>salvation
horror music>anxiety
what is priming
Change in the processing of a stimulus due to a previous encounter with the same or related stimulus…with or without conscious awareness of the original encounter
resistant to brain damage, aging and dementia
(more likely to want food after seeing advertisement, watching jaws>more scared of ocean)
what is Operant Conditioning
Learn to associate a Stimulus with a Response
Positive reinforcement (reward) leads to increase in that behavior
lack of reinforcement TENDS to decrease in that behaviour
(parenting, store loyalty, etc)
is storage of declarative and nondeclartive memories similar or different
similar
Memories are primarily stored within brain regions originally involved in processing each kind of information
is retreival of declarative and non declarative memories similar
similar because it also involves frontal lobes
HOWEVER
consolidation/learning (medial temporal structures vs motor planning brain areas) and memory storage (diffuse cortical areas) occur in different places.
how long does making a change in synaptic plasticity that will last more than a few hours requires gene transcription and protein synthesis take
several hours
How is memory affected by brain damage?
More brain damage = more severe memory impairments (mass action principle)
what are the 5 causes of memory loss
Ischemia
Traumatic Brain Injury (TBI) & Concussion
Degenerative (e.g. Alzheimer’s)
Multifocal lesions
Psychogenic amnesia – NO structural damage to temporal lobes
