Chapter 6 Memory

Chapter 6Chapter 6MemoryMemory

Chapter 6 OverviewChapter 6 Overview

The structure of human The structure of human memorymemory

The nature of rememberingThe nature of remembering How reliable is memory?How reliable is memory? Biology and memoryBiology and memory ForgettingForgetting Improving memoryImproving memory

The Structure of The Structure of Human MemoryHuman Memory MemoryMemory is the process of is the process of encodingencoding, , storagestorage, , consolidationconsolidation, and , and retrievalretrieval of informationof information

Processes required Processes required for rememberingfor remembering

Three memory systemsThree memory systems

What are the characteristics What are the characteristics of the sensory memory?of the sensory memory?

Briefly holds information Briefly holds information from the sensesfrom the senses– Visual information: for a Visual information: for a fraction of a secondfraction of a second

– Auditory information: up to 2 Auditory information: up to 2 secondsseconds

What happens to information in What happens to information in short-term memory?short-term memory?

Holds about seven (plus or Holds about seven (plus or minus two) items for less minus two) items for less than 30 seconds without than 30 seconds without rehearsalrehearsal

Also called Also called working memoryworking memory– STM acts as a workspace for STM acts as a workspace for carrying out mental activitycarrying out mental activity

What happens to information in What happens to information in short-term memory?short-term memory?

DisplacementDisplacement– When STM is full, each new, incoming When STM is full, each new, incoming item pushes out an existing itemitem pushes out an existing item

ChunkingChunking– Grouping bits of information into larger Grouping bits of information into larger units, which are easier to rememberunits, which are easier to remember

RehearsalRehearsal– Repeating information to maintain it in Repeating information to maintain it in STMSTM

Maintenance rehearsalMaintenance rehearsal Elaborative rehearsalElaborative rehearsal

What kinds of information are What kinds of information are stored in the subsystems of stored in the subsystems of long-term memory?long-term memory? Long-term memory Long-term memory has a virtually has a virtually unlimited capacity that contains unlimited capacity that contains vast stores of a person’s vast stores of a person’s permanent or relatively permanent or relatively permanent memoriespermanent memories

What kinds of information are What kinds of information are stored in the subsystems of stored in the subsystems of long-term memory?long-term memory? Declarative memoryDeclarative memory

– Stores facts and information, and life eventsStores facts and information, and life events Episodic memoryEpisodic memory Semantic memorySemantic memory

Nondeclarative memoryNondeclarative memory– Stores motor skills, habits, simple conditioned Stores motor skills, habits, simple conditioned

responsesresponses

What kinds of information are What kinds of information are stored in the subsystems of stored in the subsystems of long-term memory?long-term memory? Declarative memoryDeclarative memory

– Stores facts and information, and life eventsStores facts and information, and life events Episodic memoryEpisodic memory Semantic memorySemantic memory

Nondeclarative memoryNondeclarative memory– Stores motor skills, habits, simple conditioned Stores motor skills, habits, simple conditioned

responsesresponses

The Nature of RememberingThe Nature of Remembering

The processes that cause The processes that cause apparent memory lapses, such apparent memory lapses, such as being unable to recall a as being unable to recall a person’s name or a telephone person’s name or a telephone number, represent two of the number, represent two of the various principles that various principles that govern how we go about govern how we go about remembering things.remembering things.

What are the three methods What are the three methods used by psychologists to used by psychologists to measure memory?measure memory? RecallRecall

– Task in which a person must search Task in which a person must search memory to produce required informationmemory to produce required information

– Recall tasks are easier when Recall tasks are easier when retrieval retrieval cuescues are provided are provided

RecognitionRecognition– Task in which a person must identify Task in which a person must identify information as having been encountered information as having been encountered beforebefore

RelearningRelearning– Measures retention in terms of time Measures retention in terms of time saved when relearning material saved when relearning material compared to learning it originallycompared to learning it originally

What happens when information What happens when information must be recalled in the order must be recalled in the order in which it was presented?in which it was presented? In the In the serial position effect serial position effect recall is better for the beginning recall is better for the beginning and ending items than for the and ending items than for the middle items in the sequence middle items in the sequence – Primacy effectPrimacy effect

Tendency to recall the first items in a Tendency to recall the first items in a sequence more easily than the middle itemssequence more easily than the middle items

– Recency effectRecency effect Tendency to recall the last items in a Tendency to recall the last items in a sequence more easily than the middle itemssequence more easily than the middle items

How do environmental How do environmental conditions and emotional conditions and emotional states affect memory?states affect memory?

People recall material People recall material more easily in the more easily in the same environment in same environment in which they learned itwhich they learned it

Godden and Baddeley Godden and Baddeley (1975)(1975)– Participants memorized Participants memorized words underwater or on words underwater or on landland

– Words learned Words learned underwater were best underwater were best recalled underwaterrecalled underwater

– Words learned on land Words learned on land were best recalled on were best recalled on landland

How do environmental How do environmental conditions and emotional conditions and emotional states affect memory?states affect memory? State-dependent memory effectState-dependent memory effect

– People tend to recall information People tend to recall information better if they are in the same better if they are in the same emotional state as when the emotional state as when the information was encodedinformation was encoded

– e.g., when feeling anxious while e.g., when feeling anxious while exposed to snakes and spidersexposed to snakes and spiders

What does research evidence What does research evidence say about flashbulb memory?say about flashbulb memory?

Extremely vivid memory of an Extremely vivid memory of an event that is surprising, event that is surprising, shocking, or highly emotionalshocking, or highly emotional– These memories are not as accurate These memories are not as accurate as people believe them to beas people believe them to be

– But, about 5% of children are But, about 5% of children are capable of capable of eidetic imageryeidetic imagery

Ability to retain an image of a visual Ability to retain an image of a visual stimulus for several minutesstimulus for several minutes

How does culture influence How does culture influence memory?memory?

Culture may influence the Culture may influence the ability to remember certain ability to remember certain kinds of materialkinds of material– Elders of the Iatmul people of New Elders of the Iatmul people of New Guinea exhibit impressive memory for Guinea exhibit impressive memory for the oral history of their peoplethe oral history of their people

– The Asur people of India, who do not The Asur people of India, who do not use artificial lighting, have use artificial lighting, have exceptional memory for locationsexceptional memory for locations

How Reliable is How Reliable is Memory?Memory? Contrary to Canadian Contrary to Canadian neurosurgeon, Wilder neurosurgeon, Wilder Penfield, the human memory Penfield, the human memory does not really function does not really function like a tape recorder or like a tape recorder or video recordervideo recorder

What is meant by the statement What is meant by the statement “Memory is reconstructive in “Memory is reconstructive in nature”?nature”? People reconstruct memories, People reconstruct memories, piecing them together from a few piecing them together from a few highlights, using information highlights, using information that may or may not be accuratethat may or may not be accurate

Frederick BartlettFrederick Bartlett– Reconstructive memory processes are Reconstructive memory processes are influenced by influenced by schemasschemas

Integrated frameworks of prior knowledge Integrated frameworks of prior knowledge and assumptionsand assumptions

What conditions reduce the What conditions reduce the reliability of eyewitness reliability of eyewitness testimony?testimony? Viewing photograph of a suspect Viewing photograph of a suspect before seeing a lineupbefore seeing a lineup

When members of a lineup are When members of a lineup are viewed at the same time, rather viewed at the same time, rather than one at a timethan one at a time

When the perpetrator’s race is When the perpetrator’s race is different from that of the witnessdifferent from that of the witness

When a weapon has been used in the When a weapon has been used in the crimecrime

When leading questions are usedWhen leading questions are used

What is the controversy What is the controversy regarding the therapy used to regarding the therapy used to recover repressed memories of recover repressed memories of childhood sexual abuse?childhood sexual abuse? RepressionRepression

– Process in which traumatic memories are Process in which traumatic memories are buried in the unconsciousburied in the unconscious

Some therapists use hypnosis and Some therapists use hypnosis and guided imagery to help clients guided imagery to help clients recover repressed memories of recover repressed memories of childhood sexual abusechildhood sexual abuse

Critics argue that these therapists Critics argue that these therapists sometimes implant false memories in sometimes implant false memories in their clientstheir clients– Research indicates that imagining a Research indicates that imagining a fictitious event can lead to false memory fictitious event can lead to false memory of the eventof the event

Biology and MemoryBiology and Memory

A person’s store of memories A person’s store of memories must exist physically somewhere must exist physically somewhere in the brain. Neuronal processes in the brain. Neuronal processes are also involved in the storage are also involved in the storage of information in the brain. of information in the brain. Trauma and disorders that affect Trauma and disorders that affect brain structures, neuronal brain structures, neuronal health, or both can seriously health, or both can seriously impair memory function.impair memory function.

What roles do the hippocampus What roles do the hippocampus and the hippocampal region and the hippocampal region play in memory?play in memory? The The hippocampushippocampus plays an important plays an important role in forming role in forming episodicepisodic memories memories

Formation of semantic memories Formation of semantic memories involves the hippocampus and other involves the hippocampus and other parts of the parts of the hippocampal regionhippocampal region

The hippocampus is also involved in The hippocampus is also involved in navigational skillsnavigational skills– Posterior of hippocampus is larger in Posterior of hippocampus is larger in taxi drivers than in general populationtaxi drivers than in general population

Why is long-term potentiation Why is long-term potentiation important?important?

Long-term potentiation (LTP)Long-term potentiation (LTP)– An increase in the efficiency of An increase in the efficiency of neural transmission at the synapse neural transmission at the synapse that lasts for hours of longerthat lasts for hours of longer

LTP may be the basis for learning LTP may be the basis for learning and memory at the level of neuronsand memory at the level of neurons

When LTP is disrupted, long-term When LTP is disrupted, long-term memories are not formedmemories are not formed– Consolidation failureConsolidation failure

How do hormones influence How do hormones influence memory?memory?

The strongest and most lasting The strongest and most lasting memories are usually fueled by memories are usually fueled by emotionemotion

Presence of Presence of epinephrineepinephrine (adrenalin) (adrenalin) and and norepinephrinenorepinephrine (noradrenalin) in (noradrenalin) in the bloodstream activate the amygdala the bloodstream activate the amygdala and help imprint powerful, enduring and help imprint powerful, enduring memories for threatening eventsmemories for threatening events

Excessive levels of Excessive levels of cortisolcortisol can can interfere with memoryinterfere with memory

EstrogenEstrogen appears to improve working appears to improve working memory efficiencymemory efficiency– But post-menopausal estrogen replacement But post-menopausal estrogen replacement may increase risk of dementiamay increase risk of dementia

What kinds of memory loss are What kinds of memory loss are experienced by those who have experienced by those who have amnesia or dementia?amnesia or dementia? AmnesiaAmnesia

– Partial or complete loss of memory due Partial or complete loss of memory due to loss of consciousness, brain damage, to loss of consciousness, brain damage, or some psychological causeor some psychological cause

Anterograde amnesiaAnterograde amnesia– Inability to form new long-term memoriesInability to form new long-term memories– Case of H. M.Case of H. M.

Retrograde amnesiaRetrograde amnesia– Loss of memory for experiences that Loss of memory for experiences that occurred shortly before a loss of occurred shortly before a loss of consciousnessconsciousness

What kinds of memory loss are What kinds of memory loss are experienced by those who have experienced by those who have amnesia or dementia?amnesia or dementia? DementiaDementia

– Mental deterioration characterized by Mental deterioration characterized by impaired memory and intellect and by impaired memory and intellect and by altered personality and behavioraltered personality and behavior

– Individuals with dementia can lose Individuals with dementia can lose episodic and semantic memoriesepisodic and semantic memories

– Can result from cerebral Can result from cerebral arteriosclerosis, chronic alcoholism, arteriosclerosis, chronic alcoholism, strokesstrokes

Alzheimer diseaseAlzheimer disease– A form of dementia caused by A form of dementia caused by degeneration of brain cellsdegeneration of brain cells

– A high IQ plus lifelong intellectual A high IQ plus lifelong intellectual activity may delay or lessen Alzheimer activity may delay or lessen Alzheimer symptomssymptoms

ForgettingForgetting

Most people think of Most people think of forgetting as a problem to forgetting as a problem to be overcome, but it’s be overcome, but it’s actually not always actually not always unwelcome. Still, when you unwelcome. Still, when you need to remember particular need to remember particular information, forgetting can information, forgetting can be very frustrating.be very frustrating.

What did Ebbinghaus discover What did Ebbinghaus discover about forgetting?about forgetting?

Ebbinghaus found Ebbinghaus found that the largest that the largest amount of amount of forgetting occurs forgetting occurs very quickly, then very quickly, then it tapers offit tapers off

This relationship This relationship between time and between time and forgetting is forgetting is called the called the curve curve of forgettingof forgetting

What causes forgetting?What causes forgetting?

Can you recognize the real penny?Can you recognize the real penny? Encoding failure Encoding failure occurs when information occurs when information was never put into long-term memorywas never put into long-term memory

Decay theoryDecay theory holds that memories, if not holds that memories, if not used, fade with time and eventually used, fade with time and eventually disappeardisappear

Source: Nickerson & Adams, 1979)

What causes forgetting?What causes forgetting?

Proactive interferenceProactive interference– Information already stored in memory interferes Information already stored in memory interferes

with remembering newer informationwith remembering newer information Retroactive interferenceRetroactive interference

– New learning interferes with remembering New learning interferes with remembering previously learned informationpreviously learned information

What causes forgetting?What causes forgetting?

Proactive interferenceProactive interference– Information already stored in memory interferes Information already stored in memory interferes

with remembering newer informationwith remembering newer information Retroactive interferenceRetroactive interference

– New learning interferes with remembering New learning interferes with remembering previously learned informationpreviously learned information

What causes forgetting?What causes forgetting?

Motivated forgettingMotivated forgetting– Forgetting through suppression or Forgetting through suppression or repression to protect self from repression to protect self from painful or unpleasant informationpainful or unpleasant information

Sometimes we forget because we don’t want Sometimes we forget because we don’t want to remember somethingto remember something

Prospective forgettingProspective forgetting– Not remembering to carry out some Not remembering to carry out some intended actionintended action

Retrieval failureRetrieval failure– Not remembering something one is Not remembering something one is certain of knowingcertain of knowing

Tip-of-the-tongue phenomenonTip-of-the-tongue phenomenon

Improving MemoryImproving Memory

There are no magic formulas There are no magic formulas for improving your memory. for improving your memory. Remembering is a skill that Remembering is a skill that like any other requires like any other requires knowledge and practice.knowledge and practice.

How can organization, How can organization, overlearning, spaced practice overlearning, spaced practice and recitation improve memory?and recitation improve memory? OrganizationOrganization

– Putting information in categories, sequences, Putting information in categories, sequences, sizes, or shapes to make retrieval easiersizes, or shapes to make retrieval easier

OverlearningOverlearning– Practicing or studying material beyond the Practicing or studying material beyond the point where it can be repeated once without point where it can be repeated once without errorerror

– Overlearned material is remembered better and Overlearned material is remembered better and longer and is more resistant to interferencelonger and is more resistant to interference

Spaced practiceSpaced practice– Learning in short practice sessions with rest Learning in short practice sessions with rest periods in betweenperiods in between

– A better study technique than A better study technique than massed practicemassed practice RecitationRecitation

– Reciting, or practicing, what you have learnedReciting, or practicing, what you have learned– Students recall more if they use more Students recall more if they use more recitationrecitation