Week 5: Memory Flashcards
Historical context of memory
Dialexeis, Plato, Aristotle, Fechner, Ebbinghaus, Bartlett, James
Dialexeis
Improving memory, attention on rehearsing, method of loci to remember speeches (memory palace)
Plato
Memory is like wax, bridge between the perceptual world and world of abstractions
Aristotle
Memories are primarily composed of associations between various experiences
Fechner
Body and mind are same unity, find quantifiable relation between a stimulus and a mental sensation
Ebbinghaus
Measurement error, distribution of observations around mean, necessity to compare two conditions in light of that error, his own subject, forgetting curve
Bartlett
Remembering is constructing, aided by schemas, memories are not static
James
Study memory through its retrieval
Modalities of memory
Declarative, implicit
Declarative memory
Episodic, semantic, autobiographic
Implicit memory
Perceptual, procedural, associative (conditioning), non-associative
Episodic memory
Ability to learn, store and retrieve information about unique personal experiences that occur in daily life
Semantic memory
Knowledge about facts devoid to the circumstances of their acquisition
Autobiographical memory
Both episodic and semantic
Declarative theory (examples)
Patient CW, semantic dementia
Declarative theory
Older memories become consolidates to neocortical areas outside of the medial temporal lobe
Patient CW
Hippocampal damage, loss of ability to consolidate and remember memories, semantic memory is spared
Semantic dementia
Knowledge of words and facts is dramatically impaired, recent events are retrieved accurately
Episodic research (Tulving)
Episodic memory is hypothetical and cannot be measured by a single test
Flashbulb memories
Episodic memory for emotional events, exceptionally vivid, clear and detailed recollection people seem to have for single, emotional events they have experiences (9/11), memories are manipulated by arousal and valence dimensions
Common tests for episodic (emotional) memories
Cued retrieval, recognition task, associative memory task, subjective quality task
Cued retrieval
Determine the proportion correct of encoded words
Recognition task
Old and new words, correct recognition rates are higher for emotional words
Associative memory task
Word pairs
Subjective quality task
Remember/know, recollection, familiarity
Recollection
Detailed vivid feeling of re-experiencing (enhanced by emotion)
Familiarity
Butcher on the bus, sense that item has been previously encountered
Emotional memories are less reliable
Dissonance theory, reconsolidation theory
Dissonance theory
We recall the past in ways that optimize our current sense of self
Reconsolidation theory
We update memories with current information to keep them relevant, as a consequence of memory reactivation and retrieval changes of memory can occur over time
Hippocampus in memory
Patient HM and CW
Patient HM
Lesions in hippocampus, no episodic memory, conditioned response present
Patient CW
Lesions in hippocampus, no episodic memory, conditioned response present
Amygdala in memory
Patient SM
Patient SM
Calcification of the amygdala, urbach-wiethe syndrome, no enhanced memory for emotional items, no conditioned responses, episodic memories present
How does the amygdala enhance emotional responses?
Adrenaline during arousal –> locus coeruleus to release norepinephrine –> acts on adrenergic receptors of amygdala –> adrenergic receptor antagonists like beta-blockers (basolateral amygdala) –> block the memory-enhancing effects of adrenaline
Amygdala has strong connections to
PFC, MTL, sensory neocortex, striatum, HPA-axis, cerebellum
PFC
Influencing working memory, semantic memory, priming, extinction learning
MTL
Influencing declarative memory, memory consolidation
Sensory neocortex
Memory storing, conceptual priming, perceptual priming
Striatum
Habit learning, reward learning
HPA-axis
Hormonal memory regulation
Cerebellum
Reflexive conditioning, motor learning
MTL memory system
Hippocampus, entorhinal cortex, perirhinal cortex
Pattern separation (within hippocampus)
A process by which similar experiences or events are transformed into discrete, non-overlapping representations (hippocampal neurogenesis in dentate gyrus)
Pattern completion
During retrieval pattern completion can be achieved instead of new encoding
Spatial navigation (in the hippocampus)
Volume of the hippocampus is associated with increased navigational skills in taxi drivers
Context dependent memory
In PTSD contextualization of memories is disturbed which causes vivid flashbacks and intrusions
Areas active for retrieval of memory within or out of context
Amygdala, hippocampus, IFG
Enhanced memory contextualization
Stronger coupling between IFG and amugdala and IFG and PPA
