7A: Memory. Example: computer Our memories are less literal and more fragile The Brain is slower,...

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