Memory Studying Memory Building Memories: Encoding Memory Storage

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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?


Our two-track memory system

Automatic processing and implicit memories

Effortful processing and explicit memories


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.)


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.)


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


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 ________.


Measuring retention

Retrieval cues


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?


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?


Misinformation and imagination effects

Source amnesia

Recognizing false memories

Children’s eyewitness recall

Repressed or constructed memories of abuse?


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?


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.)


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?

Memory Studying Memory Building Memories: Encoding Memory Storage

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