Memory Part I : Encode, Store, Retrieve
I. What is Human Memory?
A. Product –
B. Process – Human memory is an information processing system that works constructively to encode, store, and retrieve information.
1. Cognitive Process
2. Interpretive Process
3. Trainable - Memory ability is greatest with information that :
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We focus our attention on…
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We are interested in…
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Arouses us emotionally…
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Is connected to our previous experiences…
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We have rehearsed/practiced repeatedly…
II. The Essential Tasks of Memory Systems
A. Encoding
The processing and modification of information into the preferred formation of the memory system.
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Selecting, identifying, and labeling our experiences.
B. Storage
The Retention of encoded information over time
C. Retrieval
The Locating and recovering information from memory
III. An Information Processing Model of Memory
* Some information skips the first two stages and enters long-term memory automatically.
A. Sensory Memory
1. Definition – A memory buffer that receives information from all the senses and is constantly monitoring all
incoming information. The immediate, initial recording of sensory information in the memory system .
2. Function – hold sights, sounds, smells, textures, and other sensory impressions for quick scan / just long enough
to be processed for basic physical characteristics
3. Capacity – 12 -16 items
4. Duration – fractions of seconds
5. Structures – Sensory registers
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Echoic – auditory – Myers: 3-4 sec
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Iconic – visual –Myers: 250 milliseconds
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Others –hepatic (tactile <1sec), olfactory, gustatory
6. Biological Basis – nerve impulses in the sensory pathways
7. Visual or iconic memory was discovered by George Sperling in 1960
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Presented matrix of letters for 1/20 seconds
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Report as many letters as possible
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Subjects recall only half of the letters
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Is this because they did not have enough time to see all the letters?
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People can see and recall ALL the letters momentarily but image memory fades (after 1/3 seconds or so)
before it can be moved into STM
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How did Sperling know this?
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When a low, medium or high tone signaled which row to repeat immediately after matrix disappeared recall
was almost perfect
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Sensory memory forms automatically, without attention or interpretation
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Attention (focusing awareness on a narrower range of stimuli or events) is needed to transfer information to working
memory….
B. Working Memory / Short Term Memory STM
1.Definition – A conscious state of selecting and preserving recently perceived events from sensory memory, associating
information with other memory stages and “thinking”.
2. Function – Control attention, Attach meaning, Make associations - Encoding
3. Capacity- seven +/- 2 items
4. Duration – 20 to 30 seconds max
What happens if you need to keep information in working memory longer than 20 seconds?
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Maintenance Rehearsal
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Mental or verbal repetition or review of information to keep it from fading while in
working memory
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Allows information to remain in working memory longer than the usual 20 -30 seconds
Chunking
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Organizing pieces of information into a smaller number of meaningful units expands
working memory load
5. Structures –
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Central Executive – directs attention
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Phonological loop – acoustic encoding
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Temporarily stores sounds of verbal patterns whether from eyes or ears
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May lead to errors due to confusion of similar sounds
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Enhances learning and language use
Sketchpad- Visual and spatial encoding
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Store and manipulate mental images
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Coordination of several brain systems/frontal and occipital
6. Biological Basis
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Hippocampus, Frontal lobes (executive processes rather than storage of memories)
7. Encoding - process that controls movement from working to long-term memory store
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Once information passes from sensory to working memory, it can be encoded into long-term memory
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Retrieval - process that controls flow of information from long-term to working memory store
a. Encoding Modification of Information
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Processes in encoding
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Select, Identify, Label
b. Automatic processing -Unconscious encoding of information
Types of information we encode automatically :
c. Effortful processing - Conscious assimilation and connection of new information to existing knowledge
Key concepts in effortful processing:
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Elaborative rehearsal
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Levels of processing
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Visual Imagery
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Self referent encoding
Rehearsal
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Conscious repetition of information, either to maintain it in consciousness or to encode it for storages
Maintenance Rehearsal
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Process of repeating or rehearsing the information
Elaborative Rehearsal
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Process in which information is actively reviewed and related to information already in LTM
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Relate info to things you already know
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Generate own examples of concepts
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Actively question new info
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Think about its implications
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Focus on the ideas
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Effortful Encoding – Simple Principles
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“Practice makes perfect” The amount remembered depends on the time spent learning (and on making it
meaningful)
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Overlearning: Additional rehearsal increases retention
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Spacing Effect: Retention better when rehearsal is distributed over time
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Massed practice can produce speedy short term learning and feelings of confidence but
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Distributed study produces long term recall
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Review mastered materials in distributed time periods related to desired recall periods
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Self Assessment serves as powerful means for learning
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Serial Position Effect – better recall of last and first items being learned
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Primacy effect
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Recency effect
The levels-of-processing principle
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Spreading out the time learning leads to higher retention of information learned
The more ways in which you think about the material, the deeper your processing will be and the more
easily you will remember the material later.
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Increase the number and types of associations made with material to be learned
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Visual
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Acoustic
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Semantic
Visual Imagery
Mental pictures (imagery) are a powerful aid to effortful processing, especially when combined with semantic encoding.
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Self Referent Encoding
The tendency for individuals to have better memory for information that relates to oneself in comparison to material that has
less personal relevance.
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Organizing Information for Meaningful Encoding
Chunking
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Organizing items into a familiar, manageable unit. Try to remember the numbers below.
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If you are well versed with American history, chunk the numbers together and see if you can recall them better.
1776 1492 1812 1941.
Hierarchy
C. Long Term Memory
1. Definition-The relatively permanent and limitless storehouse of the memory system storing information organized according to
meaning. A “web”of interconnected associations. A mental scaffold that can hold as much information as you can make
associations for.
2. Function – organizes and stores information
3. Duration - unlimited
4. Capacity- unlimited
5. Structures
a. Declarative Memory – Knowing What
Semantic -Conscious memory and recall of facts, general knowledge, and concepts
Episodic-Conscious memory and recall of personal experiences or ‘episodes’
b. Procedural Memory – Knowing How
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Involves implicit memory which affects behavior or mental processes without one being aware of it.
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Classical Conditioning
c. Evidence for Separate Implicit/Explicit Systems
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Patient H.M.
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Explicit memories acquired before the surgery left intact
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Could not form NEW explicit /declarative memories (Anterograde amnesia )
Findings
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Hippocampus (and amygdala) are crucial to laying down new episodic memories, although they seem to have no
role in retrieving old memories (Zimbardo)
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H.M. is almost normal on procedural or implicit memory tasks including priming, classical conditioning, and
learning motor skills
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Anterograde amnesia –
Inability to form memories for new information (50 First Dates)
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Retrograde amnesia –
Inability to remember information previously stored in memory (Samantha Who?)
6. Biological Basis of Memory
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Hippocampus
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Amygdala
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Neurons and Synapses
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Long Term Potentiation
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Lasting increase in synapse firing potential after brief,
stimulation
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Neural building blocks of complex memories
Neurotransmitters and Hormones
IV. Memory Retrieval
A. Measures of Memory
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Recall
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The ability to retrieve information not in conscious awareness
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Retrieval cues may be in the form of a question
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Essay tests
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Names
Recognition
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Retrieval cue in the form of identification of a previously experienced stimulus
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Multiple choice test
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Faces
Relearning
rapid
B. Retrieval Cues - Any stimulus that helps us recall information
1. Organization- Anything stored in LTM must be organized and “filed” according to its pattern or meaning. The
strength of retrieval cues depends on this filing of information and experiences
Mind spontaneously organizes stored information
2. The best cues come from associations made at the time of encoding
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Concepts and Categories : Conceptual hierarchy –multilevel classification system based on common
properties among items
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Clusters: Clustering-tendency to remember similar or related items in groups
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Contexts : The more closely the retrieval clues match the form in which the information was encoded, the
better the information will be remembered -Sounds, sights, smells, moods, physical states
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Schemas: An organized cluster of knowledge about a particular object or event abstracted from precious
experience with the object or event
3. Priming -The retrieval of memories by cues that stimulate a memory of the connection between the cue and the
retrieved memory (The “awakening” or activation of associations). Activation not a necessarily a conscious decision
a. Priming Effects -A change in thoughts, feelings, or behavior due to the unconscious prior experience or exposure
to information (even though the information was unknowingly stored and retrieval was unintentional)
b. Types of Priming
Conceptual Priming - Involves activation of concepts stored in semantic memory
The meaning of priming stimulus influences your retrieval (your flow of thoughts)
Perceptual Priming-Prime enhances ability to identify a stimulus based on its physical features
4. Encoding specificity principle
a. Context Effects- Tendency to recall experiences that are consistent with external, environmental factors
Examples: VisualOlfactoryOtherb.State-Dependent Effects - Tendency to recall experiences that are consistent with one’s internal physiological ‘state’
Examples:
c. Mood Congruent Memory - Tendency to recall experiences that are consistent with one’s current mood
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A happy mood is likely to trigger happy memories
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Depression perpetuates itself through biased retrieval of depressing memories
5. Schema Theories - Frameworks for new information and for retrieval of information
Schema - mental representation of an object, scene or event
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example: schema of a countryside may include green grass, hills, farms, a barn, cows, etc.
Scripts - type of schema involving mental organization of events in time