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Memory Studying Memory Building Memories: Encoding Memory Storage Retrieval: Getting Information Out Forgetting Memory Construction Errors Improving Memory. Studying Memory. An information-processing model. Studying Memory. Memory - PowerPoint PPT Presentation
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MemoryStudying Memory
Building Memories: Encoding
Memory Storage
Retrieval: Getting Information Out
Forgetting
Memory Construction Errors
Improving Memory
Studying Memory
An information-processing model
Studying Memory
MemoryPersistence of learning over time through the encoding, storage, and retrieval of information
Information-processing modelsUsed to help us think about how the brain forms and retrieves memories
EncodingProcess of getting information into the memory system
StorageProcess of retaining encoded information over time
RetrievalProcess of getting information out of memory storage
An Information-Processing Model
Atkinson and Shiffrin (1968): Three stages1. We first record to-be-remembered information as a
fleeting sensory memory.
2. From there, we process information into short-term memory, where we encode it through rehearsal.
3. Finally, information moves into long-term memory for later retrieval.
A MODIFIED THREE-STAGEINFORMATION-PROCESSING MODEL OF MEMORY
Atkinson and Shiffrin’s classic three-step model helps us to think about how memories are processed, but today’s researchers recognize other ways long-term memories form. For example, some information slips intolong-term memory via a “back door,” without our consciously attending to it (automatic processing). And so much active processing occurs in the short-term memory stage that many now prefer to call that stage working memory.
Information-Processing
• Working memory• Processes important, focused information
• Makes sense of new input
• Links with long-term memory
• Uses a central executive (Baddeley)
WORKING MEMORY
Alan Baddeley’s (2002) model of working memory, simplified here, includes visual and auditory rehearsal of new information. Part of the brain functions like a manager, a central executive focusing attention and pulling information from long-term memory to help make sense of new information.
What two new concepts update the classic Atkinson-Shiffrin three-stage information processing model?
What are two basic functions of working memory?
Building Memories: Encoding
Our two-track memory system
Automatic processing and implicit memories
Effortful processing and explicit memories
Building Memories: Encoding
Our two-track memory systemExplicit memories (declarative memories) of conscious facts and experiences encoded through conscious, effortful processing
Implicit memories (nondeclarative memories)that form through automatic processes and bypass the conscious encoding track
Building Memories: EncodingAutomatic processing and implicit memories
Implicit memories include automatic skills and classically conditioned associations
Information is automatically processed aboutSpace
Time
Frequency
Effortful processing and explicit memoriesWith experience and practice, explicit memories become automatic
Sensory memory
TOTAL RECALL—BRIEFLY When George Sperling (1960) flashed a group of letters similar to this for one-twentieth of a second, people could recall only about half the letters. But when signaled to recall any one row immediately after the letters haddisappeared, they could do so with near-perfect accuracy.
What is sensory memory?• First stage in forming
explicit memories• Immediate, very brief
recording of sensory information in the memory system
• Iconic memory: Picture-image memory
• Echoic memory: Sound memory
Capacity of Short-Term and Working Memory
Short-term memoryActivated memory that holds a few items briefly (such as the seven digits of a phone number while dialing) before the information is stored or forgotten
Working memoryNewer understanding of short-term memory that stresses conscious, active processing of incoming auditory and visual-spatial information, and of information retrieved from long-term memory
Capacity of Short-Term and Working Memory
Short-term memoryGeorge Miller (1956)
Magical Number Seven: People can store about seven bits of information (give or take two)
Baddeley and colleagues ( 1975)Without distraction, about seven digits or about six letters or five words
Working memoryCapacity varies by age and distractions at the time of memory tasks
SHORT-TERM MEMORY DECAY
Unless rehearsed, verbal information may be quickly forgotten (From Peterson & Peterson, 1959; see also Brown, 1958.)
Building Memories: Encoding
Effortful processing strategies
Chunking: Organizing items into familiar, manageable units; often occurs automatically
Mnemonics: Memory aids, especially techniques that use vivid imagery and organizational devices
Peg-word system
(From Hintzman, 1978.)
Building Memories: Encoding
Spaced study and self-assessmentSpacing effect: Encoding is more effective when it is spread over time
Distributed practice: Produces better long-term recall
Massive practice: Produces speedy short term learning and feelings of confidence
Repeated self-testing (testing effect) effect: Encoding is very effective
Building Memories: Encoding
Making new information meaningfulSpaced practice is most effective when new information is meaningful
EbbinghausEstimated that, compared with learning nonsense material, learning meaningful material required one-tenth the effort
Which strategies are better for long term retention: cramming and rereading material, or spreading out learning over time and repeatedly testing yourself?
Memory Storage
Retaining information in the brain
Synaptic changes
Memory Storage: Retaining Information in the Brain
Past researchWhole past is contained in memory—waiting to be relived
Newer findingsFlashbacks during surgery are new creations of a stressed brain
Information is not stored in a single, specific spot
Perception, language, emotions and more require brain networks
Explicit- Memory System: Hippocampus and Frontal Lobes
The brain registers and temporarily stores event aspects in the hippocampus
Memories then migrate for storage in memory consolidation process
Right and left frontal lobes store different information
The hippocampus and the brain cortex display rhythmic patterns of activity during sleep
THE HIPPOCAMPUS Explicitmemories for facts and episodes are processed in the hippocampus and fed to other brain regions for storage.
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Retaining Information in the Brain
Implicit memory system: Cerebellum and basal gangliaThe cerebellum plays an important role in forming and storing memories created by classical conditioning
Memories of physical skills are also implicit memories
Basal ganglia help form memories for these skills
Infantile amnesiaConscious memory of the first three years is blank
Command of language and a well-developed hippocampus are needed
Review Key Memory Structures in the Brain
Frontal lobes and hippocampus: explicit memory formation Cerebellum and basal ganglia: implicit memory formation Amygdala: emotion-related memory formation
Which parts of the brain are important for implicit memory processing, and which parts play a key role in explicit memory processing?
Your friend has experienced brain damage in an accident. He can’t remember anything told to him during a conversation. What’s going on here?
Retaining Information in the Brain
Excitement or stress trigger hormone production and provoke the amygdala to engage memory
Emotions often persist with or without conscious awareness
Flashback memories occur via emotion-triggered hormonal changes and rehearsal
Synaptic Changes
Long-term potentiation (LTP) Increase in a synapse’s firing potential
After LTP, the brain will not erase memories
Believed to be a neural basis for learning and memory
Kandel and Schwartz (1982)Pinpointed changes in sea slugs’ neural connections
With learning more serotonin is released and cell efficiency increased—number of synapses increase
Our Two Memory Systems
Which brain area responds to stress hormones by helping to create stronger memories?
The neural basis for learning and memory, found at the synapses in the brain’s memory connections, results from brief, rapid stimulation. It is called ________.
Retrieval: Getting Information Out
Measuring retention
Retrieval cues
Retrieval: Getting Information Out
Three types of evidence indicate memory retention
Recall
Recognition
Relearning
EBBINGHAUS’ RETENTION CURVE
The more times Ebbinghaus practiced a list of nonsense syllables on day 1, the less practice he needed to relearn it on day 2
Speed of relearning is one way to measure whether something was learned and retained (From Baddeley, 1982.)
Multiple-choice questions test our
a. recall. c. relearning.
b. recognition. d. sensory memory.
Fill-in-the blank questions test our ________.
If you want to be sure to remember what you’re learning for an upcoming test, would it be better to use recall or recognition to check your memory? Why?
Retrieval: Getting Information Out
Memory retrievalMemories are held in storage by a web of associations
Retrieval cues serve as anchor points for pathways to memories suspended in this web
PrimingActivation, often unconsciously, of particular associations in memory
Retrieval Cues
PRIMING—AWAKENINGASSOCIATIONS After seeing or hearing rabbit, we are later more likely to spell the spoken word as h-a-r-e
Associations unconsciouslyactivate related associations
This process is called priming (Adapted from Bower, 1986.)
Retrieval Cues
Context effectsPriming memory is often helped by returning to the context of the experience
State-dependent memoryThere is a tendency to recall events consistent with current good or bad mood (mood-congruent memory)
Serial position effectThere is a tendency to recall best the last and first items in a list
The Effects of Context on Memory
Words heard underwater were best recalled underwater; words heard on land were best recalled on land. (Adapted from Godden & Baddeley, 1975.)
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What is priming?
When we are tested immediately after viewing a list of words, we tend to recall the first and last items best, which is known as the ________ effect.
Forgetting
Forgetting and the two-track mind
Encoding failure
Storage decay
Retrieval failure
Forgetting and the Two-track Mind
Humans have two distinct memory systems, controlled by different parts of the brain
Forgetting has several causesEncoding failure
Storage decay
Retrieval failure
Interference
Motivated forgetting
Let’s look more closely at these causes.
STUDYING A FAMOUS BRAIN Jacopo Annese and of California are preserving Henry Molaison’s brain for the benefit of future generations. Their careful work will result in a freely available onlinebrain atlas.
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Forgetting: Encoding and Storage Decay
Encoding failureAge: Encoding lag is linked to age-related memory decline
Attention: Failure to notice or encode contributes to memory failure
Storage decayCourse of forgetting is initially rapid, and then levels off with time
Physical change in the brain occur as memory forms (memory trace)
FORGETTING AS ENCODING FAILURE
We cannot remember what we have not encoded.
The Forgetting Curve For Spanish Learned In School
Compared with others just completing a Spanish language-learning course, people 3 years out of the course remember much less. Compared with the 3-year group, however, those who studied Spanish even longer ago did not forget much more. (Adapted from Bahrick, 1984.)
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Forgetting: Retrieval Failure
Reason for failureEvents and memories are not available because they were never acquired
Memories have been discarded due to stored memory decay
Insufficient information to access memories make these out of reach
RETRIEVAL FAILURE
Reason for failure• Events and memories are not available because they
were never acquired• Memories have been discarded due to stored memory
decay• Insufficient information to access memories make
these out of reach
Forgetting
InterferenceProactive: Occurs when older memory makes it more difficult to remember new information
Retroactive: Occurs when new learning disrupts memory for older information
Motivated forgettingFreud: Repressed memories protect self-concept and minimize anxiety
Today: Attempts to forget are more likely when information is neutral, not emotional
RETROACTIVE INTERFERENCE
People forgot more when they stayed awake and experienced other new material. (From Jenkins & Dallenbach, 1924.)
WHEN DO WE FORGET?
• Forgetting can occur at any memory stage
• As we process information, we filter, alter, or losemuch of it
What are three ways we forget, and how does each of these happen?
Memory Construction Errors
Misinformation and imagination effects
Source amnesia
Recognizing false memories
Children’s eyewitness recall
Repressed or constructed memories of abuse?
Memory Construction Errors
Memory is not exactProactive interference: Disruptive effect of prior learning on the recall of new information
Retroactive interference: Disruptive effect of new learning on the recall of old information
7-17 How do misinformation, imagination, and source amnesia influence our memory construction? How do we decide whether a memory is real or false?
Memory Construction Errors
Misinformation and imagination effectsMisinformation effect occurs when a memory has been corrupted by misleading information
Imagination effect occurs when repeatedly imaging fake actions and events can create false memories
MEMORY CONSTRUCTION
In this experiment, people viewed a film of a car accident(left). Those who later were asked a leading question recalled a more serious accident than they had witnessed. (From Loftus, 1979.)
Memory Construction Errors
Source amnesiaInvolves faulty memory for how, when, or where information was learned or imagined
Déjà vu Sense that “I’ve experienced this before.”
Suggests cues from the current situation may unconsciously trigger retrieval of an earlier experience
Recognizing False Memories
Children’s eyewitness recallCeci and Bruck
Researchers studied the effect of suggestive interviewing techniques
58 percent of preschoolers produced false stories about one or more unexperienced events
Children often accurately recall events and actorsNeutral person
Nonleading questions soon after event containing words children can understand
Repressed or Constructed Memories ofAbuse?
Challenges related to adult recognition of childhood abuse:
People do not believe abuse survivors
Innocent people are falsely accused
Repressed or Constructed Memories ofAbuse?
Those committed to protecting abused children and those committed to protecting wrongly accused adults have agreed on the following:
Sexual abuse happens
Injustice happens
Forgetting happens
Recovered memories are commonplace
Memories of things happening before age 3 are unreliable
Memories “recovered” under hypnosis are especially unreliable
Memories, whether real or false, can be emotionally upsetting
Improving Memory
What do you do to improve your memory and increase your success in this course?