Chapter 9 Memory Table of Contents Exit. Memory: Some Key Terms Memory: Active system that stores, organizes, alters, and recovers (retrieves) information

Chapter 9

Memory

Table of ContentsTable of Contents ExitExit

Memory: Some Key Terms

Memory: Active system that stores, organizes, alters, and recovers (retrieves) information

Encoding: Converting information into a useable form

Storage: Holding this information in memory

Retrieval: Taking memories out of storage


Fig. 9.1 In some ways, a computer acts like a mechanical memory system. Both systems process information, and both allow encoding, storage, and retrieval of data.


Sensory Memory

Storing an exact copy of incoming information for a few seconds (either what is seen or heard); the first stage of memory Icon: A fleeting mental image or visual

representationEcho: After a sound is heard, a brief

continuation of the activity in the auditory system


Short-Term Memory (STM)

Storing small amounts of information briefly Working Memory: Part of STM; like a mental

“scratchpad” Selective Attention: Focusing (voluntarily) on a

selected portion of sensory input (e.g., selective hearing)

Phonetically: Storing information by sound; how most things are stored in STM

Very sensitive to interruption or interference


Long-Term Memory (LTM)

Storing information relatively permanently

Stored on basis of meaning and importance


Fig. 9.2 Remembering is thought to involve at least three steps. Incoming information is first held for a second or two by sensory memory. Information selected by attention is then transferred to temporary storage in short-term memory. If new information is not rapidly encoded, or rehearsed, it is forgotten. If it is transferred to long-term memory, it becomes relatively permanent, although retrieving it may be a problem. The preceding is a useful model of memory; it may not be literally true of what happens in the brain (Eysenck & Keane, 1995).


Short-Term Memory Concepts

Digit Span: Test of attention and short-term memory; string of numbers is recalled forward or backward Typically part of intelligence tests

Magic Number 7 (Plus or Minus 2): STM is limited to holding seven (plus or minus two) information bits at once Information Bit: Meaningful single piece of

information


More Short-Term Memory Concepts

Recoding: Reorganizing or modifying information in STM Information Chunks: Bits of information that are grouped into

larger chunks

Maintenance Rehearsal: Repeating information silently to prolong its presence in STM

Elaborative Rehearsal: Links new information with existing memories and knowledge in LTM Good way to transfer STM information into LTM


Long-Term Memory Concepts

Constructive Processing: Updating long-term memories on basis of logic, guessing, or new informationPseudo-Memories: False memories that a person believes are true or accurateMemory Structure: Pattern of associations among bits of information in LTMRedintegrative Memory: Memories that are reconstructed or expanded by starting with one memory and then following chains of association to related memories


Types of Long-Term Memories

Procedural: Long-term memories of conditioned responses and learned skills, e.g., driving Declarative: LTM factual information Semantic Memory: Impersonal facts and everyday knowledge Subset of declarative memory

Episodic: Personal experiences linked with specific times and places Subset of declarative memory


CNN – Alzheimer’s Babies


Fig. 9.3 Exposed cerebral cortex of a patient undergoing brain surgery. Numbers represent points that reportedly produced “memories” when electrically stimulated. A critical evaluation of such reports suggests that they are more like dreams than memories. His fact raises questions about claims that long-term memories are permanent (From Wilder Penfield, The Excitable Cortex in Conscious Man, 1958. Courtesy of the author and Charles C. Thomas, Publisher, Springfield, Illinois.)


Fig. 9.6 The tower puzzle. In this puzzle, all the colored disks must be moved to another post, without ever placing a larger disk on a smaller one. Only one disk may be moved at a time, and a disk must always be moved from one post to another (it cannot be held aside). An amnesic patient learned to solve the puzzle in 31 moves, the minimum possible. Even so, each time he began, he protested that he did not remember ever solving the puzzle before and that he did not know how to begin. Evidence like this suggests that skill memory is distinct from memories for facts.


Fig. 9.7 In the model shown here, long-term memory is divided into procedural memory (learned actions and skills) and declarative memory (stored facts). Declarative memories can be either semantic (impersonal knowledge) or episodic (personal experiences associated with specific times and places).


Measuring Memory

Tip-of-the Tongue (TOT): Feeling that a memory is available but not quite retrievableRecall: Direct retrieval of facts or informationHardest to recall items in the middle of a

list; known as Serial Position Effect Easiest to remember last items in a list

because they are still in STM


Fig. 9.8 The serial position effect. The graph shows the percentage of subjects correctly recalling each item in a 15-item list. Recall is best for the first and last items. (Data from Craik, 1970.)


Measuring Memory (cont.)

Recognition Memory: Previously learned material is correctly identified Usually superior to recall

Distractors: False items included with a correct item Wrong choices on multiple-choice tests

False Positive: False sense of recognitionRelearning: Learning again something that was previously learnedUsed to measure memory of prior learning


Measuring Memory (cont.)

Savings Score: Amount of time saved when relearning information Explicit Memory: Past experiences that are consciously brought to mindImplicit Memory: A memory not known to exist; memory that is unconsciously retrievedPriming: When cues are used to activate hidden memoriesInternal Images: Mental pictures


Eidetic Imagery (Somewhat Like Photographic Memory)

Occurs when a person (usually a child) has visual images clear enough to be scanned or retained for at least 30 secondsUsually projected onto a “plain” surface, like a blank piece of paperUsually disappears during adolescence and is rare by adulthood


Fig. 9.10 Test picture like that used to identify children with eidetic imagery. To test your eidetic imagery, look at the picture for 30 seconds. Then look at a blank surface and try to “project” the picture on it. If you have good eidetic imagery, you will be able to see the picture in detail. Return now to the text and try to answer the questions there. (Redrawn from an illustration in Lewis Carroll’s Alice’s Adventures in Wonderland.)


Forgetting

Nonsense Syllables: Meaningless three-letter words (fej, quf) that test learning and forgetting

Encoding Failure: When a memory was never formed in the first place

Memory Traces: Physical changes in nerve cells or brain activity that occur when memories are stored

Memory Decay: When memory traces become weaker; fading or weakening of memories

Disuse: Theory that memory traces weaken when memories are not used or retrieved


Fig. 9.11 The curve of forgetting. This graph shows the amount remembered (measured by relearning) after varying lengths of time. The material learned was nonsense syllables. Forgetting curves for meaningful information also show early losses followed by a long, gradual decline, but overall, forgetting occurs much more slowly. (After Ebbinghaus, 1885.)


Fig. 9.13 Some of the distracter items used in a study of recognition memory and encoding failure. Penny A is correct but was seldom recognized. Pennies G and J were popular wrong answers. (Adapted from Nickerson & Adams, 1979.)


Fig.9.12 Pick a card from the six shown. Look at it closely and be sure you can remember which card is yours. Now, tap all four corners of this page with your fingertip. When you’re done, look at Fig.9.14


Some More Theories of Forgetting

Memory Cue: Any stimulus associated with a memory; usually enhances retrieval of a memory A person will forget if cues are missing at retrieval time

State-Dependent Learning: When memory retrieval is influenced by body state; if your body state is the same at the time of learning AND the time of retrieval, retrievals will be improved If Robert is drunk and forgets where his car is parked, it will be

easier to recall the location if he gets drunk again!


Fig.9.14 Poof! The card you chose in Fig. 9.12 is gone. Obviously, you could have selected any one of the six cards in Fig.9.12. How did I know which one to remove? This trick is based entirely on an illusion of memory. Recall that you were asked to concentrate on one card in Fig.9.12. That prevented you from paying attention to the other cards, so they weren’t stored in your memory. The five cards you see here are all new (none were shown in Fig.9.12). Because you couldn’t find your card in the “remaining five,” it looked like your card had disappeared.


Fig. 9.15 The effect of mood on memory. Subjects best remembered a list of words when their mood during testing was the same as their mood was when they learned the list. (Adapted from Bower, 1981.)


Even More (!) Theories of Forgetting

Interference: Tendency for new memories to impair retrieval of older memories, and vice versa

Retroactive Interference: Tendency for new learning to interfere with retrieval of old learning

Proactive Interference: Prior learning inhibits (interferes with) recall of later learning


Fig. 9.17 Effects of interference on memory. A graph of the approximate relationship between percentage recalled and number of different word lists memorized. (Adapted from Underwood, 1957.)


Fig. 9.18 Retroactive and proactive interference. The order of learning and testing shows whether interference is retroactive (backward) or proactive (forward).


More on Forgetting

Positive Transfer: Mastery of one task aids learning or performing another

Negative Transfer: Mastery of one task conflicts with learning or performing another


CNN – Memory Drugs


Repression and Suppression

Repression: Unconsciously pushing painful, embarrassing, or threatening memories out of awareness/consciousness Motivated forgetting, according to some theories

Suppression: Consciously putting something painful or threatening out of mind or trying to keep it from entering awareness


Flashbulb Memories

Memories created during times of personal tragedy, accident, or other emotionally significant events Where were you when you heard that terrorists

had attacked the USA on September 11th, 2001?

Includes both positive and negative eventsNot always accurateGreat confidence is placed in them even though they may be inaccurate


Memory Formation

Retrograde Amnesia: Forgetting events that occurred before an injury or traumaAnterograde Amnesia: Forgetting events that follow an injury or traumaConsolidation: Forming a long-term memoryElectroconvulsive Shock (ECS): Mild electrical shock passed through the brain, destroying any memory that is being formed; one way to prevent consolidation


Memory Structures

Hippocampus: Brain structure associated with information passing from short-term memory into long-term memory If damaged, person can no longer “create” long-

term memories and thus will always live in the present

Memories prior to damage will remain intact

Engram: Memory trace in the brain


Ways to Improve Memory

Knowledge of Results: Feedback allowing you to check your progressRecitation: Summarizing aloud while you are learningRehearsal: Reviewing information mentally (silently) Selection: Selecting most important concepts to memorizeOrganization: Organizing difficult items into chunks; a type of reordering


Ways to Improve Memory (cont.)

Whole Learning: Studying an entire package of information at once, like a poem Part Learning: Studying subparts of a larger body of information (like text chapters)Progressive Part Learning: Breaking learning task into a series of short sectionsSerial Position Effect: Making most errors while remembering the middle of the listOverlearning: Studying is continued beyond bare mastery


Ways to Improve Memory (cont.)

Spaced Practice: Alternating short study sessions with brief rest periodsMassed Practice: Studying for long periods without rest periodsLack of sleep decreases retention; sleep aids consolidation Hunger decreases retentionCognitive Interview: Technique used to improve memories of eyewitnesses


Mnemonics: Memory “Tricks”

Any kind of memory system or aid Using mental picturesMaking things meaningfulMaking information familiarForming bizarre, unusual, or exaggerated

mental associations


Using Mnemonics to Remember Things in Order

Form a Chain: Remember lists in order, forming an exaggerated association connecting item one to two, and so on

Take a Mental Walk: Mentally walk along a familiar path, placing objects or ideas along the path

Use a system


Seven Sins of Memory (Schacter, 2001)

Transience: Stored information tends to fade with passage of time

Absent-Mindedness: Weak, poorly encoded memories tend to cause absent-mindedness

Blocking: Not being able to recall a word or a name that you know well

Misattribution: Linking a memory with the wrong source, time, or place


Seven Sins of Memory (cont.)

Suggestibility: Suggestions and misleading questions can implant information that leads us to alter or revise our memoriesBias: Memories are often distorted to match our beliefs and expectationsPersistence: Memories of traumatic events may persist for many yearsConclude: Memory limitations that appear to be flaws are actually adaptive features in some situations


Documents

Chapter 9 Memory Table of Contents Exit. Memory: Some Key Terms Memory: Active system that stores, organizes, alters, and recovers (retrieves) information