Memory Flashcards
encoding
initial processing of information so that it is represented in the nervous system (creating memory traces)
storage
retention of encoded information through consolidation
retrieval
ability of the brain to access stored information to use for some cognitive purpose - a cue (internal or external) triggers part of a memory trace, then you recall the rest
capacity
how much information can be stored in a memory system
duration
how long information remains in memory
modal model of memory (Atkinson and Shiffrin)
we have three types of memory: sensory, short-term, and long-term which each have their own capacities and durations
sensory memory according to the modal model of memory
large capacity, short duration - the sensory system holds information in place before it can be selected for further processing
temporary, automatic, no conscious effort required
short-term memory according to the modal model
smaller capacity than sensory, but longer duration (15-30 seconds) - STM can produce a behavioural output, transferring information to LTM
what is maintenance rehearsal and its function?
to prolong the duration of information in STM, it is the mental repetition of information without distractions
long-term memory according to the modal model
storage for information to be retrieved in STM and used for some cognitive function
persistence of vision
an image of a stimulus remains in our visual system after that stimulus has gone
iconic memory
Sperling’s letter grid experiment
partial report or whole report conditions of a grid of letters = could recall more of the grid in the partial report condition
types of sensory memory
iconic: visual (afterimages)
echoic: auditory (to help us separate streams of sound quickly)
haptic: touch (useful for gripping and grasping)
gustatory: taste
olfactory: smell
types of LTM
implicit: non-conscious, non-declarative
explicit: consciously accessible, declarative
visual capacity of STM
7 +/- 2 chunks/3-5 chunks
auditory capacity of STM
7 chunks
what is chunking and what does it depend on?
combining information into larger groups of meaningful units, depends on LTM (matching to memory), increases with expertise (chess novices vs. experts)
mnemonists
people with the ability to form large chunks
decay theory of forgetting
over time information leaks out
interference theory of forgetting
information processed between or before encoding affects retrieval
proactive interference (old information causes you to be unable to learn new information) and retroactive interference (new information causes you to forget older information)
examples of proactive interference and retroactive interference
pro: getting a new phone number and being unable to remember it because you keep typing in your old phone number
retro: learning a new model in psychology and being unable to remember the one it contradicted
articulatory suppression
repeating an irrelevant word to prevent rehearsal
working memory model of STM
three interconnected subunits: visuo-spatial sketchpad (visual component), phonological loop (audio component), central executive (coordinates other components and filters out distractors)
how does the working memory model explain the age decline in memory?
decline in the central executive instead of memory stores; becomes less effective at filtering out distractors
evidence against the initial working memory model
binding problem
a coherent story is better remembered = phonological loop interacts with LTM, so they are not completely separate sensory codes and instead interact with each other
episodic buffer
added component of the WM model to account for the integration of information in different stores (sketchpad, phonological loop, LTM) and is controlled by the central executive
brain regions associated with the WM model
occurs all over the brain (whichever sensory experience is involved)
dorsolateral PFC could be the central executive
episodic buffer in the parietal lobe
phonological loop in Broca’s and Wernicke’s
visuo-spatial sketchpad in the occipital lobe
attentional control in the anterior cingulate cortex
function of the hippocampus
encoding memories of complex events as patterns of activity across the cortex (depending on the nature of the memory)
over time the memory trace can become independent from the hippocampus
types of implicit memory
procedural
priming
types of explicit memory
semantic
episodic
afterimages
positive: represents the perceived image
negative: inverse of the perceived image (colours are inverted)
serial position effects and their mechanisms
primacy effect: information presented first is better remembered because of increased rehearsal = benefits from LTM processes
recency effect: final information is better remembered because it is stored in STM (increase delay to more than 30 seconds eliminates the effect)
evidence for dissociable WM memory stores
neuroimaging studies: different active brain regions for verbal and visual tasks
double dissociation in neuropsychological cases: patients have selective deficits to STM regarding visual-spatial and verbal tasks
mechanisms of the phonological loop
phonological store: passive storage for verbal information (“inner ear”)
articulatory control loop: active rehearsal of verbal information (“inner voice”), converts written material to sounds
mechanisms of the visuo-spatial sketchpad
visual cache: stores feature information (colours, form), passive
inner scribe: holding and working with information about sequence, movement, spatial location; active (processing changes)
Ebbinghaus’ experiment
tested how nonsense syllables (no access to knowledge) were retained and forgotten over time
study syllables without inflection, at a constant slow pace
developed the forgetting curve: exponential (memory loss is largest early on, then decreases)
ways to slow the forgetting curve
active rehearsal: speaking and working with the syllables
spacing effect: taking breaks between encoding sessions and varying the review sessions (differences in shorter bursts)
levels of processing theory
how we encode information affects whether we’re going to forget it (the strength of the memory)
shallow processing
focus on sensory features = likely to forget that information
deep processing
integrating higher-level information (meaning, evaluating, making connections to prior knowledge) = better memory
deep and shallow encoding of faces experiment
upright/inverted faces: focus on sensory features = shallow processing (better memory for upright because of holistic processing in FFA)
actor/politician faces: links to prior knowledge = deep processing (better memory than upright/inverted)
naming mnemonic
using acronyms like ROY G. BIV to remember the colours of the rainbow
story mnemonic
creating a story out of a list of words
method of Loci
associating pieces of information with a location/visual image (mind palace)
visceral/emotional aspects are better remembered
leaves a neural imprint - different neuronal connections
types of deep encoding
self-reference effect: information attached to oneself
generation effect: generated content is better remembered than passively read
encoding-specificity hypothesis
memory retrieval is better than when there is overlap with encoding context (context can act as a retrieval cue - internal state and external environment)
state-dependent learning
mental and physiological states match at encoding and recall = better retrieval (sober-sober and drunk-drunk conditions)
external environment effect on retrieval experiment
deep-sea divers were better at recalling learned words when external environment matched (underwater-underwater or land-land conditions)
episodic memory
encoding and recalling unique events within temporal and spatial context (re-experiencing)
semantic memory
information you know without remembering the context in which you learned it (societally shared general knowledge)
includes facts about yourself
semantic dementia
episodic memory is preserved (can copy images from memory)
cannot access concept knowledge, faces, names, words, functions of objects
common in Alzheimer’s
temporal poles are damaged, anterior temporal lobe
hippocampal damage
episodic memory dependent on the hippocampus - damage to it impairs ability to copy images after a delay, but semantic memory is preserved
anoetic consciousness
implicit memory: no conscious awareness (tying shoes, riding a bike)
no awareness and no personal engagement
noetic consciousness
semantic memory: aware that you’re consciously accessing information, but you don’t recall where/how you learned it
awareness without personal engagement
autonoetic consciousness
episodic memory: mental time travel to context to remember how you learned information
awareness and personal engagement
personal semantics
an intermediary types of semantics that involves information about the self and things that occur repeatedly in your life (autobiographical facts - my brother’s name & repeated events - I walked my brother to school every day)
reappearance hypothesis
idea that memories are encoded a certain way and stays that way (will be recalled the same way)
people with PTSD were recalling highly emotional events the same way = appears fixed
flashbulb memories
vivid memories of significant public events (emotionally arousing), retreiving specific details about time and place
still reconstructed memories - details change but vividness and confidence in them increased
evidence for the reconstruction of flashbulb memories
OJ Simpson trial: recollections changed and people experienced major distortions
people closer to the World Trade Center on 9/11 had more vivid, detailed, confident memories
how to construct an episodic memory trace
hippocampus binds together details processed in different brain areas and re-activates them at retrieval (may bring forth different combinations of details = memory changes)
consolidation vs. reconsolidation
consolidation is the initial storage from STM to LTM
once a trace gets re-activated, it is unstable and subject to change
it must be re-consolidated back into LTM which can alter the neural network
applications of reconsolidation
because memories become unstable, the memory could be changed/erased - eliminating fear responses in PTSD and phobias
role of schemas in memory
can lead to distortions based on your expectations
can lead to false memories - falsely endorsing a recollection of a schema-consistent lure
War of Ghosts experiment
Ps read an unfamiliar Native American folk story (did not match schema-consistent Western story structure) - their recall changed to match their schema (lost details over time, omitted strange details and altered others to become more conventional)
engaged in assimilation
Roediger-McDermot paradigm
semantically-related lures are falsely reported to be part of episodic memories (influence of semantic memory on episodic)
how are false memories formed?
familiar feeling = incorrect associations
altered at retrieval by context, suggestion, misinformation
misattribution effect
retrieving familiar information from the wrong source (match context to the wrong memory)
misattribution of familiarity (thinking your prof works at your grocery store because they seem familiar)
misinformation effect
leading questions lead to false memories: ‘contacted’ vs. ‘smashed’ = details added to original memory
adaptive functions of reconstructive memory
we can reconstruct and form hypothetical situations in our mind (planning the future)
decision-making, creativity, problem-solving
overlap in neural activity during recollection and imagining the future
retrograde amnesia
events leading up to the brain injury are lost (typically loss of personal memories, not semantic and self-identity) - Kayla Hutchison also lost language and basic skills and semantic knowledge
anterograde amnesia
unable to encode new memories after a brain injury
Patient H.M. and Clive Wearing
HM bilateral lobectomy of the medial temporal lobe - able to form procedural memories (non-declarative memory depends on the basal ganglia)
cognitive abilities were intact
STM was fine
Wearing encephalitis = hippocampal damage - intact piano-playing, language, proper behaviour, facts about the world
Patient K.F. and Alzheimer’s patients
KF - damage to STM systems (which are not the hippocampus)
Alzheimer’s show less connectivity between PFC and hippocampus, damaged STM/WM
transfer-appropriate processing
retrieval depends on whether the cue matches the way information was encoded + how well it was encoded (“what word rhymed with bat?” cued-recall condition vs. free-recall)
spacing effect and testing effect
information is better remembered if it is presented over multiple spaced-out periods
information is better remembered when asked to retrieve it on your own than passive exposure
brain regions associated with episodic and semantic memory
episodic: occipital and temporal (sensory details)
semantic: frontal and parietal (executive function and decision-making, abstracted representations)
procedural memory and its associated brain regions
learned abilities to perform an automatic behavioural action (more immune to forgetting)
basal ganglia refines action sequences and shapes habits
PFC organizes procedures and monitors them
prejudice as a type of memory
implicit; inclination to automatically judge something positively/negatively based on past experience
familiarity effect of prejudice and its relation to propaganda
more likely to judge something positively if you have encountered it before
propaganda: people more likely to endorse a statement as true if they have heard it before (even if told it is false)
conditioning as a type of memory
implicit; making stable, long-term connections, fear learning & phobias (associations remain despite explicit memory being forgotten)
relies on structures in the limbic system other than the hippocampus
synaptic consolidation
within the synapses: long-term potentiation (structural changes like the number of receptors or NTs released)
stable change that occurs quickly
systems consolidation
making new connections between neurons in the cortex (relies on the hippocampus; hippocampal replay)
more permanent than synaptic consolidation
hippocampal replay
sequence of brain activity is replayed after initial encoding
what is the function of the medial prefrontal cortex in episodic memory?
activates schemas and prior knowledge to integrate within an episodic memory - acts as a scaffold onto which details are added
formation of habits
initially depend on explicit memory but with training and exposure will become implicit
can be motor sequences or repetitive thoughts, emotions
requires the striatum
how to extinguish a habit
inhibit the PFC, replace the habit behaviour with another behaviour (changing/removing the reward doesn’t work) - rats t-maze experiment
priming
prior exposure facilitates processing without awareness
implicit emotional responses
fear responses
amygdala critical for this types of memory (Free Solo movie - amygdala needs a higher level of stimulation to be activated and produce a fear response)
spreading activation in a semantic network
automatic activation spreads to interconnected concepts and features, semantically related concepts also become activated
structure of semantic representations in the brain
modality-specific aspects (action, sound, emotion, colour) and abstracted representations in convergence zones (inferior and lateral temporal lobes and inferior parietal cortex)
Ribot’s law
retrograde amnesia is temporally graded; most recent memories are more affected than more remote memories
dissociative amnesia
retrograde amnesia for episodic memories and autobiographical knowledge - leads to shifts in lifestyle (new identity)
usually a response to psychological trauma
hypometabolism in lateral PFC = impaired executive processes, difficulty accessing stored memories (but they are there)
dementia and memory loss
Alzheimer’s begins with cell death in the medial temporal lobes (hippocampus) = episodic memory deficits, then spreads to other parts of the cortex
offset and treatment of Alzheimer’s
sleep, bilingualism, engaging the brain in a variety of activities can offset progression
music can help management of symptoms (alternate procedural memory pathway)
symptoms of semantic dementia
anomia: loss of word meaning and finding
cannot name functions of objects, calls objects ‘thingies’
cannot access details about concepts (all four-legged animals become dogs)
healthy aging effects on memory
brains shrink, mostly the frontal cortex and hippocampus
implicit and semantic memory are intact
episodic is impaired
deficits in general cognitive processing: lower processing speed, difficulty inhibiting distractors
associative-deficit hypothesis and evidence
problems encoding and retrieving associations
no trouble recognizing someone, but difficulty knowing where they come from (accessing episodic memory)
not due to attentional problems: younger adults still outperform older in a face-name association task while being distracted
evidence of adaptive cognitive aging
high-performing memory older adults recruited the bilateral PFC whereas young adults and low-performing OA recruited the right PFC (neural compensation for deficits)
evidence of individual differences in episodic memory
taxi drivers had increased grey matter of posterior hippocampi (smaller anterior) and better spatial memory (related to years of experience)
HSAMs
Highly Superior Autobiographical Memory
greater accuracy for episodic memories without using strategies (no increased abilities for other types of memory)
memory is still constructive, they just have more details to work with
how to test for HSAM
dates quiz: ask something you can verify for a particular day (weather, day of the week)
public events quiz: when did a particular event happen?
downsides of perfect memory
more prone to imagining future and constantly replaying the past
higher prevalence of OCD
difficult to form social networks because of a disconnect from peers
overly focused on small details = problems recognizing faces, cannot focus on general concepts
