Memory (unit 6)

psychology

Memory

• combine info we have w new info coming in

• indication learning has persisted (store & retrieve info)

Information Processing Model of Memory

3 stages:

1. Encoding

2. Storage

3. Retrieval

Encoding

1st step to creating a new memory

• item converted into construct → stored in brain + recalled from S/L term memory 

• begins w perception through senses 

Storage 

step 2

• ability to store info (diff for stages of mem formation) 

ex. sensory, short/long term, perm long term 

Retrieval 

step 3 

• reassessing events/info from past 

• (info previously encoded/stored in brain)

Three Stage Model of Memory 

• sensory input → recorded as fleeting sensory mem

• info processed in STM

• encoded in LTM → later retrieval 

Sensory Memory- Iconic Memory

• fast decaying store of visual

• less than a sec 

• retain impressions of sensory info after stimulus ceases

• demonstration: sperlings photographic recall test 

Echoic Memory

• fast decaying store of auditory 

• last: few secs 

• demonstration: last few words of sentence

Sperling’s Iconic Memory Experiment

• flashed letters on screen (1/20th of sec) 

• letters recalled = ½

• then: used high/med/low tones → almost perfect 

Sensory Memory: Info Processing

Encoding:

• accepts info from all senses, very fleeting (little encoding) 

Storage: 

• holds info for few secs (or less) 

Retrieval: 

• limited # of recent sensory input can be recalled 

STM & WM

• active processing of info

• associates new/old info 

• solves problems 

• limited duration

Capacity of STM

limited: can store 7 bits of info (± 2) → Miller 

STM: Information Processing

Encoding:

• sensory info must be attended to for encoding

Storage: 

• holds for less than 1 min

Retrieval: 

• holds 4-7 items 

LTM? Capacity? 

• anything you remember from more than a few mins ago 

• last days/years 

• capacity: unlimited/perm, not as accurate as sensory/STM, info stored in diff locations 

LTM: Explicit (Declarative)

• processed in hippocampus 

includes: 

• facts/gen knowledge

• personal experiences

• consciously recalled info  

LTM: Implicit (Non-Declarative)

• retention outside conscious recollection 

• processed in: cerebellum/other 

• motor/cog skills 

Patient H.M. (Henry Molaison)

• epileptic seizures → removed parts of temp lobe (prevent seizures)

• explicit mem from before surgery (couldn’t remember after) 

• retained implicit mem 

Biology of Memory- Hippocampus 

• processes explicit mem 

• mem → other area for storage 

• limbic system 

• active during slow wake sleep 

Biology of Memory- Cerebellum

• forms implicit mem 

• forming/storing mem created by CC

• damage: disrupts forming conditioned reflexes 

Long Term Potentiation (LTP)

• neural basis for learning/remembering associations

• synapses become more efficient at transmitting msgs 

LTM: Information Processing

Encoding:

• requires LTP, ↑ w elaborative/semantic processing of new info 

Storage: 

• holds for days-years (no known capacity) 

Retrieval: 

• perm, not always accurate 

Autonomic v. Effortful Processing

A = unconscious encoding of info about space/time/well learned info 

E = encoding requires attention/effort (ex. rehearsal) 

Ebbinghaus + Retention (Forgetting) Curve

• studied his mem, memorize nonsense syllables

• more time rehearsed = less time next day

shows:

• retain info through repetition

Spacing Effect

• info retained better when rehearsal = distributed over time → better LT recall

• massed practice → ST learning, poor LT recall

The Serial Position Effect

tendency to remember 1st/last items in a list

Chunking? Mnemonic?

C: break into smaller groups

M: mem aid uses visual imagery

Hierarchies 

• broad concepts broken into smaller concepts/facts

• then divided even narrower

• = organizational encoding

Organizational Encoding: Studying

focus

• outlines/headings/preview questions/self test

Elaborative Rehearsal

• associate new info w already stored knowledge (hierarchies) 

• analysis of new info → make memorable 

• mental pictures (imagery) 

• deep processing 

3 Strategies for Succesful Encoding 

Semantic: words meaning → deeper processing, best mem 

Rhyme: words sound → shallow processing 

Visual: how word looks → shallow processing, lowest remembering

Recognition v Recall

Reco: identify item among other choices

Recall: retrieve info using effort 

Context Effects v. State-Dependent Memory

CE: better recall in sim environment to where you learned info

SD: better recall in sim mood in which you learned info, emotions = retrieval clues 

Flashbulb Memories

• clear/detailed

• mem of emotionally significant events 

Emotion & Memory 

• em triggered stress hormones (↑ glucose) → signals to brain something important occurred 

• amygdala boosts activity & proteins in brain mem areas 

Tips to improve memory

• distributed practice 

• meaningful/em connections 

• retrieval cues 

• mnemonic devices 

• sleep 

• self test

Seven Sins of Memory: Persistence

• intrusive recollection of events we wish to forget

• often after traumatic events (PTSD) 

Seven Sins of Memory: Transience

• forgetting what occurs w passage of time 

• mems decay if not used 

• info at first = rapidly forgotten → gradually levels off

Transience: Prolonged Stress + Memory 

• heightened em → stronger mems of em significant events 

• prolonged stress can worsen mem 

Seven Sins of Memory: Absentmindedness (prospective?)

= lapse in attention results in mem failure 

• failure of encoding 

• prospective mem: remember to do things in future 

Seven Sins of Memory: Blocking

• failure to retrieve info present in mem

• even though you’re trying to produce it (tip of tongue)

Seven Sins of Memory: Misattribution 

= assign idea to wrong source (frontal lobe)

• source mem: recall when/where/how info acquired 

• false recognition: feeling of familiarity for something not previously encountered 

Seven Sins of Memory: Suggestibility 

incorporate misleading info from external sources into personal recollection → develop false mem 

False Memory: Misinformation Effect 

incorporate misleading info into mem of an event

= imagining nonexistent events can create mem, can be planted

Seven Sins of Memory: Bias? (consistency/change/egocentric)

present beliefs/knowledge unconciously distort recollection of past events

• consistency bias: reconstruct past to fit present 

• change bias: exaggerate differences b/w current/ past beliefs

• egocentric bias: exaggerate change b/w past/present to make ourselves look better