7A: Memory
Example: computerOur memories are less literal and more fragileThe Brain is slower, but can does many things at once
ConnectionismModern Memory model
We first record to be remembered info as fleeting: sensory memory
From there we process info into short-term memory, where we encode it through rehearsal
Information than moves onto long-term memory for later retrieval
Modified three-stage processing External events (sensory input)->Sensory
memory (Encoding)/Important info)->Working/Short-term memory (Encoding and Retrieving)->Long-term memory
Short-term: last about a minute (#)Working memory: memories that last for
days or weeks (stays longer) but not permanently (studying)
Working MemoryConcentrates on active processing of infoPeople’s working memory capacity differs
How we EncodeAutomatic Processing: unconscious
encoding of informationEx: Where you ate dinner yesterday?Parallel Processing: doing many things at
once
Effortful Processing: encoding that requires attention and conscious effortEx: What is standard deviation?
Automatic Processing• Space: example when studying you often
encode the place on a page and if struggling will try to visualize
• Time: unintentually note the sequence of today’s events
• Frequency: keep track of how many times things happen
• Well-learned information: register words with meaning
Effortful Processing• Durable and accessible memories• We can boost our memory through
rehearsal• The amount remembered depends on the
time spent learning • Overlearning-additional rehearsal increases
retention (practice is key)
Effortful ProcessingSpacing effect: we retain information
between when rehearsal is distributed over time
Mass practice (cramming) can produce speedy short-term learning and confidence but distributed study time produces better long-term recall
Effortful ProcessingSpreading out learning (over a semester)
helps not only on final exams but also retaining that information for a lifetime (testing effect)
Spaced study and self-assessment beats cramming
Effortful Processing: Serial Effect• Our tendency to recall the first best the last
and first items in a list• Primacy (first): Remembered items at the
beginning of the list• Recency (recent): Remembered items
come at the end of the list/most recent• Von Restorff effect: exception: when
information is list is unique (president example)
Levels of ProcessingVisual encoding-picture/imagesAcoustic encoding-soundSemantic encoding-meaning
Processing a word deeply by its meaning produces better recognition later than does shallow processing such as appearance or sound
Self-reference effect: good recall of information when it is meaningful to us
Visual EncodingImagery-mental pictures, powerful aid to
effortful processing especially when combined with meaning
Mnemoic: memory aidsCan also help organize material for later
retrieval
Organizing information for EncodingChunking: organizing items into familiar
units (occurs automatically)Hierarchies: composed of a few broad
concepts divided and subdivided into narrower concepts and facts
Encoding: selective attentionhttp://www.youtube.com/watch?v=IGQmdo
K_ZfY
Storage: retaining information
Sensory memoryIconic memory: momentary memory of visual
stimuliFleeting photographic memory
Echoic memory: momentary memory of auditory stimuliLinger for 3 to 4 seconds
Both have helped the initial recording of sensory info
Working/Short-term MemoryLimited in duration and capacityShort-term memory better for random
digits than random lettersAt any given moment we can consciously
process only a very limited amount of info
Long-term MemoryOur capacity for storing long-term
memories is essentially limitless
Storing Memories in the BrainWe don’t store information in discrete
precise locationsEx: Rats in maze
Synaptic ChangesMemory trace?Nerve cells must communicate through
their synapses/ Thus to understand the basis of memory we have to look how neurons communicate with one another via their neurtransmitter messangers
Synaptic ChangesWe know experience (age) does increase
neural interconnections to form or strengthen
Increased synaptic efficiency makes for more efficient neural circuits. The sending neuron now needs less prompting to release its neurotransmitter and the receiving neuron’s receptor sites may increase
Long-term potentiationProlonged neural firing provides a neural
basis for learning and rememberingRats given a drug that enhances LTP
learned a maze with half the usual # of mistakes
LTPPharamceutical companies competing to
develop memory-boosting drugsOne approach is developing drugs that
boost production of the protein CREBThus lead to increased production of proteins
that help reshape synapses and consolidate short-term into long-term memory
LTPDrugs that boost glutamate, a
neurotransmitter that enhances synaptic communication
Most effective, safe, and free memory enhancer…….
LTPAfter LTP has occurred, passing an electric
current through the brain won’t disrupt old memories, but will wipe out very recent memoriesEx: Blow to the head (football players)
Stress Hormones and Memory in BrainStronger emotional experiences make for
stronger, more reliable memoriesPeople given a drug that blocks the effects
of stress hormones will have trouble remembering the details of an upsetting storyEx: rape victim
Video clip on Stress and Memory-AP Collins
Limits to stress-enhanced rememberingSustained abuse or combat: can shrink the
hippocampus When stress hormones are flowing older
memories may be blockedEx: Stressed rats have harder time finding
their way out of the maze
Storing implicit and explicit memories
Anmesia: unable to form new memoriesDestroyed conscious recall not unconscious
capacityImplict: “how to do something”
Motor skills, bike ridindExplicit: People may not be able to explain how
they know to do something
HippocampusDamage to this area disrupts memory
Left: trouble remembering verbal informationRight: trouble recalling visual designs or
locationsActive when we sleep: loading dock while
the brain register and temporarily holds the episode
Simultaneous activity between the brain while sleeping
Once stored, we activate various parts of the frontal and temporal lobes
The CerebellumThe brain region at the rear of the
brainstem, which forms and stores the implicit memories created by classical conditioning
When damaged, people cannot develop certain conditioned reflexesEye test: puff of air
Retrieval: Getting Information OutRecall: the ability to retrieve information
not in conscious awarenessEx: 5 minute clip you have seen before, fill in
the blankRecognizing: person identifies previously
learned materialEx: unit test (multiple choice)
Relearning: Amount of times saved when learning material for a second time
Retrieval CuesMemories are stored in a web of
associationsAnchor points you can use to target
information you want to retrieve laterMneomic DevicesBest come from associations we form at
the time we encode the memory (5 senses)
Retrieval Cues-Priming“Wakening of associations”Invisible memory without explicit
rememberingBehaviors can be primed in social
situations
Context EffectsPutting yourself back in the context where
you experienced something can prime your memory retrievalEx: pencil, desk
Déjà vu: being in a similar context to one we’ve been in before may trigger the experienceThe current situation may be loaded with
cues that unconsciously retrieved an earlier similar experience
Don’t pay attention to the details around us
Moods and Memory State-dependent memory what at we learn
in one state may be more easily recalled when we are again in that state
Emotions become retrieval cuesWhen happy we recall happy events, see the
world as a happy place, thus prolongs our good mood
When depressed, we recall sad events, which darkens our interpretation of current events
Forgetting Three sings of forgetting
Absent –mindedness-in attention to details leads to encoding failure (our mind is elsewhere)
Transience-storage decay over time (unused info fades)
Blocking-inaccessibility of stored information (retrieval failure)
ForgettingThree sins of distortion
Misattribution-confusing the source of info (dream)
Suggestibility-lingering effects of misinformation
Bias-belief colored recollections (feelings )
ForgettingOne sin of intrusion
Persistence-unwanted memories (sexual assault)
Encoding FailureAge can affect encoding efficiency
Helps age-related memories declineWithout effort, many memories never formPenny example
Storage DecayForgetting Curve: the course of forgetting is
initially rapid then levels off with timeWhy?
It is a gradual fading of the physical memory trace
Accumulation of learning that disrupts our retrieval
Occurs when the retrieval process does not produce a complete response but produces parts. Forgetting as a result of retrieval failure rather than encoding or storage failure
Retrieval FailureContribute to the occasional memory
failures of older adults who are frustrated by the tip-of-the-tongue forgetting
Interference and Motivated Forgetting
Retrieval Failure: InterferenceProactive interference: occurs when
something you learned earlier disrupts your recall of something you experience later
Retroactive interference: occurs when new information makes it harder to recall something you learned earlierInformation presented in the hour before
sleep is protected from retroactive inference because the opportunity for interfering evens is minimized
When should you study?
Proactive or retroactive?I’ve used my locker combination for years.
One day I had to learn a new one for just one day. Now I can’t remember my old one.
I keep calling my new girlfriend by my old girlfriend’s name!
Retrieval Failure: Motivated ForgettingPeople unknowingly revise their own
histories Sigmund Freud: he proposed that we
repress painful memories to protect our self-concept and to minimize anxiety
Many people disagree saying that its extremely hard to forget emotional memories or traumatic experiences
Video clips-AP Collins
Memory Construction We infer our past from stored information
plus what we later imagined, expected, saw, and heard
Eye witness testimony
Memory Construction: Misinformation and Imagination effectsMisinformation effect: after exposure to
subtle misinformation, many people misremember
Hard to discriminate between real and suggested events
The more vividly we can imagine things, the more likely we are to inflate them into memories
Memory Construction: Source AmnesiaWe retain the memory of the event, but not
of the context in which we acquired itEx: Rumor mill
Memory Construction: Discerning True and False MemoriesMuch as perceptual illusions may seem like
real perceptions, unreal memories feel like real memories
Memories we derive from experience have more detail than memories we derive from imagination
Why memories are so fallible: Our imagination and expectation are very powerful
Memory Construction: Discerning True and False MemoriesMemories of imagined experiences are
more restricted to the gist of the supposed event-the associated meaning and feelings
Because gist memories are durable, children’s false memories sometimes outlast their true memories especially as children mature
Memory Construction: Children’s Eyewitness RecallInterviewers who ask leading question can
plant false memoriesChildren can testify if they have not talked
with the involved adult prior to the interview and when their disclosure is made in a first interview with a neutral person who ask non-leading questions
Repressed or Constructed Memories of AbuseSexual abuse happens: no characteristic “survivor
syndrome”Injustice happens: some innocent people have been
falsely convictedForgetting happens: both negative and positiveRecovered memories are commonplace: cued by a
remark or an experienceMemories before the age of 3 are unreliable: infantile
amnesiaMemories “recovered” under hypnosis or the
influenced of drugs are especially unreliableMemories whether real or false can be emotionally
upsetting
Elizabeth Loftus: main issues that occupy researchersPeople are prone to mis-information when
time allows the original memory to fadeYoung people are susceptible to the
misinformation effectSome have argued that the original
memory traces are changed by post-event information
Misleading info can turn a lie into memory’s truth
Elizabeth Loftus and Impossible MemoriesTo show that reconstructed memories are
not just amalgamations of actual experiences
Video clip on AP Collins
Improving MemorySQ3R-Survey, Question, Read, Rehearse, Review-
Unit 1Study repeatedly: exercise memories, wait timeMake the material meaningful: form images,
understand and organize info, relate to what you already know
Activate retrieval cues: re-create the situation and the mood in which your original learning occurred
Use mnemoic devices: chunk items, rhymesMinimize interference: study before sleepingSleep moreTest your own knowledge-self-assessment