memory models structures processes l.
Skip this Video
Loading SlideShow in 5 Seconds..
Download Presentation

Loading in 2 Seconds...

play fullscreen
1 / 97


  • Uploaded on


I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'MEMORY: MODELS, STRUCTURES, PROCESSES' - johana

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

AcknowledgmentsPlease note that some of the figures and pictures included were adapted from:

defining memory
Defining memory
  • Memory – the means by which we draw on our past experiences to use the information in the present
  • Memory as a process – it refers to the dynamic mechanisms associated with retaining and retrieving information about past experience
  • Three common operations of memory:

1. encoding – transformation of sensory data into a

form of mental representation

2. storage – keeping encoded information in memory

3. retrieval – pulling out or using information stored in memory

deficient memory amnesia
Deficient memory: amnesia
  • Amnesia = severe loss of memory
  • Anterograde amnesia
    • difficulty in remembering things that happened from the time of a trauma onward
  • Retrograde amnesia
    • loss of one’s purposeful memory for events prior to a trauma
  • - a case reported by Russell and Nathan (1946): a man suffered from amnesia after a motorbike accident in 1933,
  • upon questioning, he gave the date as February 1922, and believed himself to be a schoolboy; he had no recollection of the intervening years, but then gradually recovered his memories, starting from the more distant past and progressing up to the time of the trauma
  • by 10 weeks after the accident, he was able to recall everything that had happened to him up to a few minutes prior to the accident
infantile amnesia
Infantile amnesia
  • TASK- write down 10 concrete words that come to your mind (e.g., sea, shop, dog, etc.)
  • Swap your list of words with the person sitting next to you.
  • Look at each word and try to recall the EARLIEST memory connected with the object it denotes (e.g., when you see the word DOG try to recall when you first saw a dog as a small child, or when you see the word SOUP, think of the very first memory you have as a small child eating soup); put your approximate age next to each memory
infantile amnesia7
Infantile amnesia
  • Infantile amnesia - inability to recall events that happened when we were very young
  • generally, we can remember little or nothing prior to the age of 3
  • but: memories of significant events (births, deaths)
  • the accuracy of childhood memories is questionable (covert and overt suggestions about the material)
outstanding memory mnemonists
Outstanding memory: mnemonists
  • Mnemonists = demonstrate extraordinary memory ability, usually based on a special technique for memory enhancement
  • Examples:
  • „S.” reported by Alexander Luria (1968);
    • his memory had no limits,
    • could reproduce extremely long strings of words even after 15-16 years,
    • depended on the mnemonic of the visual imagery,
    • converted material into visual images (RED-> a man in a red shirt coming toward him; 3- a gloomy person; 6- a man with a swollen foot)
outstanding memory mnemonists9
Outstanding memory: mnemonists
  • synesthesia – experiencing sensations in a sensory modality different from the sense that is physically stimulated (e.g., automatically converting a sound into a visual image)
  • V.P. (Hunt & Love, 1972) could memorize long strings of material (rows and columns of numbers),
    • relied on verbal translations,
    • memorized numbers by transforming them into dates, and then thought about what he had done on that day
  • S.F. (Ericsson, Chase, and Faloon, 1980) remembered long strings of numbers by segmentingthem into groups of 3 or 4 digits and encoding them as running times for different races (he was an experienced long-time runner)
    • developed his mnemonic ability after 200 practice sessions distributed over the period of 2 years-
    • increased his memory for digits more than 10-fold (he started as a regular subject with the average recall of about 7 digits)
outstanding memory mnemonists10
Outstanding memory: mnemonists
  • the work with S.F. suggests that a person with a fairly typical level of memory can be converted into one with quite an extraordinary memory (with a great deal of concerted practice)
  • Disadvantages of a mnemonic memory:
    • synesthesia may interfere with the listening abilities (voices cause blurs of sensations),
    • abstract concepts (cannot be visually imagined)- difficult to understand
tasks used for measuring memory
Tasks used for measuring memory

Recall = a task to produce a fact, a word, or other item from memory (eg. fill-in-the-blanks tests), based on expressive knowledge

  • serial – in the exact order in which items were presented
  • free – random order
  • cued – first presentation of items in pairs, then only one item to recall its mate
tasks used for measuring memory12
Tasks used for measuring memory
  • Recognition = a task to select or identify an item as being one that you learned previously (eg. multiple choice, true-false), usually better than recall, based on receptive knowledge

explicit tasks –requiring a conscious recollection – we are to recall or recognize words, facts, or pictures from a particular prior set of items

implicit tasks – performance is assisted by previous experiences which we do not consciously try to recollect, eg. word-completion tasks (m_m_ _ _)

we perform better when the word has been presented recently (memory priming), even amnesiacs perform well on cued-recall tasks

tasks involving procedural vs declarative knowledge
Tasks involving procedural vs. declarative knowledge
  • procedural knowledge – „knowing how” skills, eg. how to drive a car
  • declarative knowledge – „knowing that”, factual information, e.g. your name, address etc.
  • amnesiacs perform well on procedural memory tasks
    • they may also improve their achievement in declarative memory tasks if they involve some procedural elements (eg. puzzles, motor skills)
traditional model of memory atkinson and schiffrin
Traditional model of memory(Atkinson and Schiffrin)
  • William James (1890):
    • primary memory (for temporary information currently in use)
    • secondary memory (for permanent store of information).
  • Richard Atkinson and Richard Shiffrin (1968) distinguished 3 memory stores:
    • sensory store – capable of storing limited amounts of information for very brief periods of time
    • short-term store – capable of storing information for longer periods of time, but also relatively limited
    • long-term store – capable of storing information for very long periods of time, perhaps even indefinitely
the three stores model sensory store
The three-stores model: Sensory store
  • sensory store is the initial repository of information that then enters short-term and long-term stores
  • strong evidence for an iconic store – visual sensory register where information is stored in the form of icons (visual images, visual persistence)
sensory store
Sensory store
  • keeps accurate record of sensory information for brief time to select important stimuli for later processing
  • produces modality specific cognitive codes
  • short duration of information
  • visual (iconic): 200-400 milliseconds
  • auditory (echoic): 2.5 - 3 seconds
  • unattended stimuli decay
the three stores model sensory store19
The three-stores model: Sensory store
  • Sperling’s discovery (1960)
    • how much information can we encode in a single brief glance at a set of stimuli?
    • flashed an array of letters and numbers on a screen for 50 milliseconds
    • subjects were to recall the symbols and their location



sperling s task
  • subjects always recalled about 4 symbols
  • to measure what the subjects saw, Sperling first used a whole-report procedure
  • then a partial-report procedure-> report one line of the digits only



sperling s task23
  • partial-report procedure-suggested that the iconic store can hold about 9 -12 items, and then it decays rapidly (when cued 1 second later, the recall was down to 4 or 5 of the 12 items)
  • we are subjectively unaware of such a fading phenomenon, because we are rarely exposed to such short stimuli and we are unable to distinguish what we see in iconic memory from what we actually see in the environment;
  • disadvantage of the method: output interference (verbally reporting multiple symbols interferes with iconic memory)
sensory store subsequent refinement
Sensory store – subsequent refinement
  • Averbach & Coriell (1961)
    • subjects reported only a single letter at a time to minimize output interference;
    • with reduced output interference the capacity of iconic store may be of as many as 12 items(75% of the 16 letters presented in the original display)
  • Another experiment suggested that iconic memory can be erased- visual sensations need to disappear rapidly for us to function well in the environment.
  • They used backward visual masking – placement of one stimulus where another one had previously appeared.
sensory store subsequent refinement26
Sensory store – subsequent refinement
  • Another experiment suggested that iconic memory can be erased
    • visual sensations need to disappear rapidly for us to function well in the environment.
  • They used backward visual masking – placement of one stimulus where another one had previously appeared.
sensory store subsequent refinement29
Sensory store – subsequent refinement
  • presentation within 100 milliseconds superimposes the mask on the letter (e.g. „F” followed by „L” would be „E”)
    • at longer intervals the mask erased the original stimulus (e.g. „F” followed by „L” would be „L”)
  • at still longer intervals between the target and the mask, the mask no longer interfered-> the target information had already been transferred to more durable memory store

(run a demo on Backward Masking-Consciousness)

the short term store
The short-term store
  • memory for matters of seconds (sometimes of up to a couple of minutes)
  • holds a few items and some control processes that regulate the flow of information to and from long-term store
  • the recall is influenced by e.g. the number of syllables pronounced with each item, the more syllables the fewer items recalled
  • Miller (1956) – capacity of the short-term store is of 7 items +/- 2 (words or digits or chunks of numbers)
the short term store31
The short-term store
  • Stores codes: Acoustic, Verbal, Semantic
  • Longer Duration of information:
  • Unrehearsed Material: ~30 seconds
  • Rehearsal builds representation into LTS
  • Unattended Stimuli Fade: Decay, Interference
the long term store
The long-term store
  • keeps memories over long periods of time, perhaps indefinitely, we rely on it heavily
  • it is impossible to establish its capacity
  • Penfield (1955, 1969): performed operations on epileptic patients using electrical stimulation of certain parts of the cerebral cortex, patients recalled remote memories  long-term memories are permanent
  • criticism of Penfield’s findings: only few of his many patients had remote memories, was it really recalling or just inventing?
  • study on memory for names and faces by Bahrick, Bahrick and Wittlinger (1975) – names and photos of former classmates, good recognition and matching results even after many years
  • perma-store (Bahrick) = long-term storage of some information (foreign language, mathematics)
long term memory
Long Term Memory
  • Permanent store, unlimited capacity
  • Information in LTM (Bower, 1975)
    • Knowledge of words, language
    • Our spatial model of the world
    • Knowledge of physical laws
  • LTM storage and structure: Info. coded acoustically, visually, semantically
  • Storage: Copy information from STS→LTS
  • Retrieval: Copy information from LTS→STS
  • LTS codes are permanent
  • Interference from other LTS code may prevent retrieval
long term memory35
Long Term Memory
  • Tulving (1972) proposed a distinction into:
    • semantic memory = general world knowledge, facts that are not unique to us, without any temporal context (historical events, literary and historical figures, the ability to recognize family, friends, info learned at school
    • episodic memory = personally experienced events or episodes, temporal context is crucial (also called autobiographical memory)
  • Acc. to Tulving, episodic memory requires three elements:
    • a sense of subjective time
    • autonoetic awareness (ability to be aware of subjective time)
    • a „self” that can travel in subjective time
semantic vs episodic memory
Semantic vs. episodic memory
  • Tulving’s findings are supported by neurological investigation and cognitive research (K.C. – lack of autonoetic consciousness)
    • suffered closed-head injury at 30
    • intact language, intelligence, reading, writing, thought processes; knowledge of school subjects,
    • knows many objective facts concerning his own life (date of birth, address, etc.)
    • BUT: amnesia for personal experiences (covering whole life); he cannot „time travel” either to the past or to the future
long term memory40
Long Term Memory
  • Declarative (explicit, conscious): “Knowing that”
    • measured by RECALL & RECOGNITION
  • Episodic memory: events
    • autobiographical—personal
  • Semantic- knowledge about the world
    • fairly constant knowledge structure
    • information about language
long term memory41
Long Term Memory
  • -Nondeclarative (implicit, procedural, unconscious, nonintentional): “Knowing how” (e.g.knowing how to ride a bicycle, ability to use language)
    • classical conditioning
    • emotional conditioning
    • priming
levels of processing lop
Levels of processing (LOP)
  • Craik and Lockhart (1972)
    • there is no specific number of stores
    • there are an infinite number of levels of processing at which items can be encoded, with no boundaries between one level and the next
    • the level of storage of information depends on how it is encoded.
    • the deeper the level of processing, the higher the probability that an item may be retrieved.
levels of processing lop44
Levels of processing (LOP)

Is the word (TABLE) written in capital letters?



Does the word (CAT) rhyme with MAT?

Is the word (DAFFODIL) a type of plant?


levels of processing lop45
Levels of processing (LOP)
  • self-reference effect(Rogers, Kuiper, Kirker, 1977) – subjects show high levels of recall when asked to relate words meaningfully to themselves
  • self-reference effect - connected with self-schema = an organized system of internal cues regarding ourselves, our attributes and personal experiences
    • we encode and organize information related to ourselves better than about other topics
  • criticism of LOP – circular definition, paradoxes in retention, strategies that use rhymes produce better retention than those based on semantics
working memory
Working memory

(Baddely & Hitch, 1974; Baddeley, 1992)

  • alternative explanation to passive STM
  • WM active in cognitive processing
  • STM actually a component of WM
  • place where cognitive operations are carried out
working memory47
Working memory
  • working memory comprises:
    • visuospatial sketchpad – briefly holding visual images
    • articulatory (phonological) loop – briefly holds inner speech for verbal comprehension and acoustic processing
    • central executive – coordinates attentional activities and governs responses, moves items in and out of short-term memory and integrates information arriving from the senses and long-term memory
working memory49
Working memory
  • part of long-term memory
  • comprises short-term memory
  • holds only the most recently

activated portion of long-term memory and moves the activated elements into and out of temporary memory storage

  • governs the processes of memory (encoding and integrating information into meaningful arrangements, which can be reformatted later)
major components central executive
Major components: Central Executive
  • central pool of mental resources
  • controlling attentional mechanism
  • coordinates activities with subsystems
  • initiates control and decision processing,

language comprehension,

  • transfers information to LTS via rehearsal
major components visual spatial sketch pad
Major components: Visual-Spatial Sketch Pad
  • subsidiary slave system
  • visual imagery tasks, spatial information, visual search
  • manipulates visual images, rotation
major components phonological loop
Major components: Phonological Loop
  • Recycles information for immediate recall; composed of:

1. Phonological store

    • retains speech-based info. for ~ 2 sec.
    • if information is not rehearsed, it fades away

2. Articulatory control process

    • controls subvocal rehearsal
    • translates visual informaiton into speech-based code and deposits it in the phonological store
major components phonological loop53
Major components: Phonological Loop
  • refreshes trace in phonological store, offsetting the decay process.
  • retention of information- a trade-off between the decay rate and covert rehearsal rate.
  • if rehearsal doesn't occur in 2 sec memory trace for that time decays.
major components the episodic buffer
Major Components:The Episodic Buffer
  • functions as backup store capable of serial recall and integrates phonological, visual and possibly other types of information
memory processes
Memory Processes


The processes are sequential, but also interactive and interdependent.


for brief storage and

temporary use

(initial encoding)


  • Conrad (1964): letters (either seen or heard) are encoded by how they sound: despite the fact that the letters were presented visually, errors tended to be based on acoustic confusability;
  • Baddeley (1966): short-term memory relies primarily on an acoustic rather than a semantic code- performance is much worse for the visual presentation of acoustically similar words;
phonological loop
Phonological Loop
  • Phonological Similarity: Memory worse for items that sound alike
  • (Conrad, 1964)

1 Z L Q N K S J

2 P B V C T D G

  • (Baddely, 1966)



  • 2 is more difficult than 1 for immediate recall
phonological loop58
Phonological Loop
  • If items presented aloud: immediate access to phonological store- it is already in sound-based code;
  • if items presented visually, they must be converted into acoustic information
    • this creates more interference as phonological similarity increases
  • If this conversion is prevented, no phonological similarity effect is recorded
phonological loop59
Phonological Loop
  • Articulatory suppression: Stop translating visual information into sound
  • Count # of letters in the sentence

I want my MTV

while you repeat the word “THE”

phonological loop60
Phonological Loop
  • this activity occupies articulatory control processes
  • preventing information from being converted into sound and being stored in the phonological store - eliminating the similarity effect
  • -BUT there should be a similarity effect for auditory stimuli because it doesn't have to be translated into sound. It is already in sound-based info. (see table 4.1. in p. 71)
encoding in wm
  • Shilman (1970), Wickens, Dalezman & Eggemeire (1970): there is some semantic encoding in short-term memory (although encoding in STM is primarily acoustic, there may be some secondary semantic encoding as well);
  • Posner & Keele (1967): temporary visual encoding might be present as well (very briefly);
  • Conclusion: acoustic form of encoding is primary in working memory
phonology in working memory
Phonology in Working Memory
  • Your teacher will dictate to you sixteen words from List A. Listen and try to memorize the words. Afterwards, write down as many as you can recall (90 seconds).
  • Now you will hear List B, also of sixteen words. Again, listen and try to memorize them. Afterwards, write down those that you recall.
  • Compare notes on which words you remembered.
  • Did the position of the words in the list have any effect?
  • Is there any difference in the number of words recalled from List A and those from List B? If so, what is the reason?
  • Did you notice when memorizing List B that some of the words begin with the same letters? Or not?
phonology in working memory63
Phonology in Working Memory
  • word-length effect: Short words (man, dog) recalled better than longer words (gentleman vs. canine)
  • the syllable based word-length effect: Words with fewer syllables recalled better than equivalent words that have more syllables.
  • why? Number of items immediately recalled depend on how often each item can be rehearsed subvocally by the articulatory control process - process used to refresh the decaying traces in the phonological store.
  • the shorter the items (in terms of pronunciation), the more items can be rehearsed before trace decays.
encoding in wm65
  • the time-based word-length effect: When items are equated for meaning and frequency, if one set of words take less time to pronounce than another set, memory will be better for the shorter items (BUT SEE TABLE 4.4, p. 77 of text)!
applied issues and wm
Applied Issues and WM
  • Working Memory and Reading Skills
  • people with large WM span especially skilled in guessing meaning of unusual words based on sentence context
wm and iq
WM and IQ
  • IQ tests rely on memory span: items recalled in order of presentation
  • Ellis & Hennelly (1980) showed that the apparent differences in memory span and IQ between Welsh-English bilinguals and English monolinguals may be due to the relative longer time needed to pronounce Welsh digits compared to English digits.
  • the fact that it takes more time to pronounce digits 1-9 in Welsh than English, reduces the number of items that can be recalled correctly. Welsh English speakers have higher memory spans and higher measures of intelligence when tested in English;
encoding for long term storage
  • Experiments:
  • Grossman &Eagle (1970): semantic confusion in a word recognition test (semantically related distractors were confused for words that originally appeared in the learning list)
  • Bousfield (1953): clustering words into semantic categories in a free-recall task;
encoding for long term storage69
  • Frost (1972): evidence for visual and semantic encoding in long-term memory (pictures of objects differing in visual orientation: angled to the right, left, horizontal or vertical);
  • Nelson &Rothbart (1972): acoustic information can also be encoded in long-term memory;
  • Conclusion: there is no one form of encoding for long-term storage.
  • Current question: When do we encode in which ways?
forgetting in working memory
FORGETTING in working memory
  • Interference theory:

competing information causes forgetting;

  • Decay theory: information disappears with the passage of time;
forgetting in working memory 2
FORGETTING in working memory 2


the ‘Brown – Peterson’ paradigm

  • Brown (1958), Peterson & Peterson (1959): trigram recalling task of strings of 3 letters ( K B F) with backward counting during the retention interval (the time between the presentation of the last letter and the start of the recall phase-to prevent people from rehearsing): counting backward interfered with recall;
  • the trigram was completely forgotten after just 18 s if subjects were not allowed to rehearse it

Two kinds of interference (inhibition):

  • retroactive – caused by the interfering material that occurs after learning something;
  • proactive – the interfering material occurs before learning of the material to be remembered;

The Brown – Peterson task may actually involve both types of


serial position curve
Serial-Position Curve
  • the serial-position curve represents the probability of recall of a given word, depending on its serial position (order of presentation);
    • best recall for items at or near the end of a list due to a recency effect (+ proactive but not retroactive interference)
    • second best recall for items near the beginning of a list due to a primacy effect (+ retroactive but not proactive interference)
    • the poorest recall for items in the middle – subject to both types of interference.
forgetting in working memory73
FORGETTING in working memory
  • Proactive interference grows (Underwood, 1957):
  • - with the length of time between encoding and retrieving a given information,
  • - with the increase in the amount of prior learning
forgetting in working memory74
FORGETTING in working memory
  • DECAY theory: information is lost because of the gradual disappearance, rather than displacement, of the memory trace
  • Problem: to test how the original information gradually disappears, subjects must be prevented form rehearsing, but without the possibility of interference with other information stored in the memory: it is very difficult to prevent people from rehearsing, even inadvertently (Try, for example, not to think of white elephants, as you read the next two lines)
forgetting in working memory decay theory
FORGETTING in working memory- DECAY THEORY
  • Reitman (1971, 1974) used tone detection as the intervening task (ss were to press the button each time they heard the tone) – it involved a great deal of effort and attention but no learning.
  • SS saw 5 words for 2 sec; as soon as the display went off, they engaged in the tone-detection task for 15 sec, after which they tried to recall as many of the 5 words as they could; recall declined by about 24% over the 15 seconds
forgetting in working memory76
FORGETTING in working memory

Interference vs decay


  • stronger evidence for the interference theory, but both types affect short-term memory;
  • the extent of proactive and retroactive interference is uncertain;

Moreover, interference affects long-term memory as well.

transfer from working to long term memory
TRANSFER from working to long-term memory
  • Transfer depends on the type of memory involved:
    • e.g. habituation, priming – volatile
    • BUT e.g. procedural memory – more stable and readily maintained, particularly as a result of repeated practice;
  • Various methods are used to transfer information to long-term declarative memory.
  • dealing with the information consciously in order to comprehend it;
  • making connections or associations – integrating new information into stored information (consolidation),
  • metamemory strategies – reflecting on one’s own memory processes.
transfer from working to long term memory78
TRANSFER from working to long-term memory
  • rehearsal – repeated recitation of an item, which produces practice effects.
    • Overt rehearsal, e.g. performed aloud
    • Covert rehearsal – silent and hidden


  • the distribution of study sessions over time affects the consolidation of information in long-term memory; (Ebbinghaus, 1885);
  • in the long run distributed practice (in sessions spaced over time) is more effective than massed practice(all at once); (Bahrick & Phelbs, 1987);
  • the spacing effect(greater recall for distributed learning) occurs because with each session the context for encoding is enriched and alternative encoding strategies may be used; (Glenberg, 1979)
transfer from working to long term memory79
TRANSFER from working to long-term memory

The total-time hypothesis: the amount of learning depends on the amount of time spent rehearsing rather than on how the time is divided into trials. The time, however, should actually be used for rehearsing that enhances recall.

Maintenance rehearsal - repetitious rehearsal; temporarily maintains information in STM;

Elaborative rehearsal– more meaningful and more memorable- necessary to transfer info into LTM- one way to elaborate information is to organize it

transfer from working to long term memory80
TRANSFER from working to long-term memory
  • organization of information
  • Stored memories are organized


  • individually determined

ways of organizing

memories – subjective

organization in free

recall, e.g. Bousfield


mnemonic devices
  • specific techniques to aid memory, which involve metamemory and add meaning to otherwise meaningless or arbitrary lists of items.
  • Roediger (1980): the effectiveness of the encoding method depends on the purpose of recalling the information; a good strategy allows not only to encode but also to retrieve the information easily.
  • Norman (1988) suggests the use of rather straightforward reminders (external memory aids), such as forcing functions – physical constrains that prevent from acting without considering the key information to be remembered (tying knots in your handkerchief, etc.)
mnemonic devices82
  • Interactive images – link the isolated words in a list;
  • Pegword system – associating new words with a word on a previously memorized list and forming an interactive image (One is a bun. Two is a shoe. Three is a tree. Four is a door. Five is a hive.);
  • Method of loci – visualizing a walk around an area with distinctive landmarks and linking them to specific items to be remembered.
mnemonic devices83
  • Acronyms – devising a word or expression in which each letter stands for a certain other word or concept
  • Acrostic – a sequence of words in which the first letters stand for sth (Bida Kac-Bach-

BIsia, DAktyl, KACper, BAmbi, CHmurka)

  • Keyword system – forming an interactive image that links thesound and meaning of a foreign word with the sound and meaning of a familiar word.
development of memory differences in metacognitive processes
  • Younger children lack both metamemory skills and the inclination to use the strategies they do know; (Appel, 1972), (Flavell & Wellman, 1977);
  • The inability is even greater for mentally retarded children; however, their performance may also be improved; (Brown, Campione, Bray & Wilcox, 1973);
  • Culture, experience, and environmental demands influence the use of memory strategies as well;
development of memory differences in metacognitive processes86
  • Moreover, memory skills involve cognitive monitoring, which consists in:
    • predicting one’s degree of accurate recall,
    • planning strategies,
    • monitoring one’s behavior.
  • Brain maturation and increasing content knowledge are also responsible for the differences in metamemory skills.
difficulties in studying retrieval processes
Difficulties in studying retrieval processes
  • Difficulties:
  • separating storage from retrieval phenomena: apparent memory failures may be caused by retrieval rather than storage failures, e.g. Tulving & Pearlstone (1966);
  • distinguishing between:
  • - availability – the idea that information is permanently stored in long-term memory;
  • - accessibility – the degree to which we can gain access to the available information;
  • assessing availability
processes of memory construction the constructive nature of memory
Processes of MEMORY CONSTRUCTION: the constructive nature of memory

Memory retrieval is both

  • reconstructive - retrieves the original memory traces and rebuilds the original experiences,
  • constructive – experience and knowledge affects what is recalled and how.
memory construction
  • effects of prior knowledge on encoding and retrieval
  • Bartlett (1932): subjects who read a culture-specific legend distorted their recall, rendering the story more comprehensible with regard to their own culture.
  • Conclusion: Prior knowledge and expectations have a substantial effect on memory and may lead to interference or distortion as well as to enhancement of memory processes.
memory construction90
  • effects of subsequent knowledge on retrieval
  • Loftus, Miller & Burns (1978) studied the validity of eyewitness testimonies and found that people are susceptible to distortion of such accounts.
  • Conclusion: people can construct memories that are different from what really happened.
  • Eyewitness identification is weaker when identifying people of a race other that that of the witness; e.g. Bringham & Malpass (1985).
The sitting room was next to the library.
  • The library only had one door.
  • The key was on the inside of the library door.
  • There were people in the sitting room at the time of the murder.
  • Nobody had heard any noise from the library.
  • The library door had to be forced open.
  • There was a fireplace to the left of the body.
  • The victim was a man.
  • The victim was killed with blows to the head.
  • The fireplace was on the wall facing the door.
  • The body was face downwards.
  • The body was lying on the rug.
  • A vase had been broken.
  • There were two windows to the library.
  • The curtains in the library were drawn.
  • There was a terrace at the rear of the house.
  • It had rained on the night of the murder.
context effects on encoding and retrieval
CONTEXT EFFECTS on encoding and retrieval
  • Existing schemata may provide a cognitive context for memory processes, e.g. experts have elaborate schemata in their areas of expertise, so they easily integrate and organize new information, implement appropriate metacognitive strategies, etc; expertise enhances confidence in recollected memories; e.g. Chase & Simon (1973);
  • The perceived clarity of an experience (vividness & richness of detail) also tends to create confidence in the accuracy of recall; e.g. Johnson & Raye (1981);
  • However, a vivid and detailed recall is not always accurate!
context effects on encoding and retrieval93
CONTEXT EFFECTS on encoding and retrieval
  • Flashbulb memory – recollection of an unusually distinctive event that is so vivid and detailed as if it was indelibly preserved on film, possibly due to:
    • its emotional intensity (Bohannon, 1988),
    • the effects of rehearsal (Bohannon, 1988),
    • confidence in the accuracy of the memories (Weaver, 1993).
  • Still, flashbulb memories may not be more reliably accurate than any other memories

(Neisser & Harsch, 1993)

memory task
  • As quickly as you can, give answers to the following questions:
  • -A plane crashed on the border between America and Canada. Where do you think the survivors were buried?
  • -How many animals of each kind did Moses lead into the ark?
context effects on encoding and retrieval95
CONTEXT EFFECTS on encoding and retrieval
  • Moods and states of consciousness also affect encoding and later retrieval; people tend to retrieve information more easily while being in the same mood or state of consciousness as during the encoding stage (e.g. Baddeley, 1989).
  • External context may affect recall as well; people recall information better when present in the same context as at the time of learning (Godden & Baddeley, 1975);
  • Context effects on memory are present from infancy

(Butler & Rovee-Collier, 1989)

context effects on encoding and retrieval96
CONTEXT EFFECTS on encoding and retrieval
  • Conclusion: Retrieval strongly interacts with encoding
    • When information is encoded in various contexts, it may be retrieved more readily in various contexts.
    • How items are encoded strongly affects how (well) they are retrieved – encoding specificity,
  • e.g. Tulving & Thomson (1973): recall (generally considered more difficult) may in fact be easier than recognition when there is a strong association between a cue and a given memory;
  • A cue is most helpful when it is meaningful to the individual (their own rather than imposed), compatibile with the target word but distinctive (not generating large numbers of related words).